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authorscuri <scuri>2008-10-17 06:10:15 +0000
committerscuri <scuri>2008-10-17 06:10:15 +0000
commit5a422aba704c375a307a902bafe658342e209906 (patch)
tree5005011e086bb863d8fb587ad3319bbec59b2447 /src/libpng
First commit - moving from LuaForge to SourceForge
Diffstat (limited to 'src/libpng')
-rw-r--r--src/libpng/png.c798
-rw-r--r--src/libpng/png.h3540
-rw-r--r--src/libpng/pngconf.h1483
-rw-r--r--src/libpng/pngerror.c341
-rw-r--r--src/libpng/pnggccrd.c101
-rw-r--r--src/libpng/pngget.c901
-rw-r--r--src/libpng/pngmem.c608
-rw-r--r--src/libpng/pngpread.c1584
-rw-r--r--src/libpng/pngread.c1472
-rw-r--r--src/libpng/pngrio.c167
-rw-r--r--src/libpng/pngrtran.c4284
-rw-r--r--src/libpng/pngrutil.c3163
-rw-r--r--src/libpng/pngset.c1246
-rw-r--r--src/libpng/pngtrans.c662
-rw-r--r--src/libpng/pngvcrd.c1
-rw-r--r--src/libpng/pngwio.c234
-rw-r--r--src/libpng/pngwrite.c1514
-rw-r--r--src/libpng/pngwtran.c572
-rw-r--r--src/libpng/pngwutil.c2792
19 files changed, 25463 insertions, 0 deletions
diff --git a/src/libpng/png.c b/src/libpng/png.c
new file mode 100644
index 0000000..40dd854
--- /dev/null
+++ b/src/libpng/png.c
@@ -0,0 +1,798 @@
+
+/* png.c - location for general purpose libpng functions
+ *
+ * Last changed in libpng 1.2.21 October 4, 2007
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#define PNG_NO_EXTERN
+#include "png.h"
+
+/* Generate a compiler error if there is an old png.h in the search path. */
+typedef version_1_2_22 Your_png_h_is_not_version_1_2_22;
+
+/* Version information for C files. This had better match the version
+ * string defined in png.h. */
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+/* png_libpng_ver was changed to a function in version 1.0.5c */
+PNG_CONST char png_libpng_ver[18] = PNG_LIBPNG_VER_STRING;
+
+#ifdef PNG_READ_SUPPORTED
+
+/* png_sig was changed to a function in version 1.0.5c */
+/* Place to hold the signature string for a PNG file. */
+PNG_CONST png_byte FARDATA png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+#endif /* PNG_READ_SUPPORTED */
+
+/* Invoke global declarations for constant strings for known chunk types */
+PNG_IHDR;
+PNG_IDAT;
+PNG_IEND;
+PNG_PLTE;
+PNG_bKGD;
+PNG_cHRM;
+PNG_gAMA;
+PNG_hIST;
+PNG_iCCP;
+PNG_iTXt;
+PNG_oFFs;
+PNG_pCAL;
+PNG_sCAL;
+PNG_pHYs;
+PNG_sBIT;
+PNG_sPLT;
+PNG_sRGB;
+PNG_tEXt;
+PNG_tIME;
+PNG_tRNS;
+PNG_zTXt;
+
+#ifdef PNG_READ_SUPPORTED
+/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+/* start of interlace block */
+PNG_CONST int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
+
+/* offset to next interlace block */
+PNG_CONST int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
+
+/* start of interlace block in the y direction */
+PNG_CONST int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
+
+/* offset to next interlace block in the y direction */
+PNG_CONST int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
+
+/* Height of interlace block. This is not currently used - if you need
+ * it, uncomment it here and in png.h
+PNG_CONST int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
+*/
+
+/* Mask to determine which pixels are valid in a pass */
+PNG_CONST int FARDATA png_pass_mask[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
+
+/* Mask to determine which pixels to overwrite while displaying */
+PNG_CONST int FARDATA png_pass_dsp_mask[]
+ = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+
+#endif /* PNG_READ_SUPPORTED */
+#endif /* PNG_USE_GLOBAL_ARRAYS */
+
+/* Tells libpng that we have already handled the first "num_bytes" bytes
+ * of the PNG file signature. If the PNG data is embedded into another
+ * stream we can set num_bytes = 8 so that libpng will not attempt to read
+ * or write any of the magic bytes before it starts on the IHDR.
+ */
+
+#ifdef PNG_READ_SUPPORTED
+void PNGAPI
+png_set_sig_bytes(png_structp png_ptr, int num_bytes)
+{
+ if(png_ptr == NULL) return;
+ png_debug(1, "in png_set_sig_bytes\n");
+ if (num_bytes > 8)
+ png_error(png_ptr, "Too many bytes for PNG signature.");
+
+ png_ptr->sig_bytes = (png_byte)(num_bytes < 0 ? 0 : num_bytes);
+}
+
+/* Checks whether the supplied bytes match the PNG signature. We allow
+ * checking less than the full 8-byte signature so that those apps that
+ * already read the first few bytes of a file to determine the file type
+ * can simply check the remaining bytes for extra assurance. Returns
+ * an integer less than, equal to, or greater than zero if sig is found,
+ * respectively, to be less than, to match, or be greater than the correct
+ * PNG signature (this is the same behaviour as strcmp, memcmp, etc).
+ */
+int PNGAPI
+png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
+{
+ png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+ if (num_to_check > 8)
+ num_to_check = 8;
+ else if (num_to_check < 1)
+ return (-1);
+
+ if (start > 7)
+ return (-1);
+
+ if (start + num_to_check > 8)
+ num_to_check = 8 - start;
+
+ return ((int)(png_memcmp(&sig[start], &png_signature[start], num_to_check)));
+}
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+/* (Obsolete) function to check signature bytes. It does not allow one
+ * to check a partial signature. This function might be removed in the
+ * future - use png_sig_cmp(). Returns true (nonzero) if the file is PNG.
+ */
+int PNGAPI
+png_check_sig(png_bytep sig, int num)
+{
+ return ((int)!png_sig_cmp(sig, (png_size_t)0, (png_size_t)num));
+}
+#endif
+#endif /* PNG_READ_SUPPORTED */
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+/* Function to allocate memory for zlib and clear it to 0. */
+#ifdef PNG_1_0_X
+voidpf PNGAPI
+#else
+voidpf /* private */
+#endif
+png_zalloc(voidpf png_ptr, uInt items, uInt size)
+{
+ png_voidp ptr;
+ png_structp p=(png_structp)png_ptr;
+ png_uint_32 save_flags=p->flags;
+ png_uint_32 num_bytes;
+
+ if(png_ptr == NULL) return (NULL);
+ if (items > PNG_UINT_32_MAX/size)
+ {
+ png_warning (p, "Potential overflow in png_zalloc()");
+ return (NULL);
+ }
+ num_bytes = (png_uint_32)items * size;
+
+ p->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
+ ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes);
+ p->flags=save_flags;
+
+#if defined(PNG_1_0_X) && !defined(PNG_NO_ZALLOC_ZERO)
+ if (ptr == NULL)
+ return ((voidpf)ptr);
+
+ if (num_bytes > (png_uint_32)0x8000L)
+ {
+ png_memset(ptr, 0, (png_size_t)0x8000L);
+ png_memset((png_bytep)ptr + (png_size_t)0x8000L, 0,
+ (png_size_t)(num_bytes - (png_uint_32)0x8000L));
+ }
+ else
+ {
+ png_memset(ptr, 0, (png_size_t)num_bytes);
+ }
+#endif
+ return ((voidpf)ptr);
+}
+
+/* function to free memory for zlib */
+#ifdef PNG_1_0_X
+void PNGAPI
+#else
+void /* private */
+#endif
+png_zfree(voidpf png_ptr, voidpf ptr)
+{
+ png_free((png_structp)png_ptr, (png_voidp)ptr);
+}
+
+/* Reset the CRC variable to 32 bits of 1's. Care must be taken
+ * in case CRC is > 32 bits to leave the top bits 0.
+ */
+void /* PRIVATE */
+png_reset_crc(png_structp png_ptr)
+{
+ png_ptr->crc = crc32(0, Z_NULL, 0);
+}
+
+/* Calculate the CRC over a section of data. We can only pass as
+ * much data to this routine as the largest single buffer size. We
+ * also check that this data will actually be used before going to the
+ * trouble of calculating it.
+ */
+void /* PRIVATE */
+png_calculate_crc(png_structp png_ptr, png_bytep ptr, png_size_t length)
+{
+ int need_crc = 1;
+
+ if (png_ptr->chunk_name[0] & 0x20) /* ancillary */
+ {
+ if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
+ (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
+ need_crc = 0;
+ }
+ else /* critical */
+ {
+ if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
+ need_crc = 0;
+ }
+
+ if (need_crc)
+ png_ptr->crc = crc32(png_ptr->crc, ptr, (uInt)length);
+}
+
+/* Allocate the memory for an info_struct for the application. We don't
+ * really need the png_ptr, but it could potentially be useful in the
+ * future. This should be used in favour of malloc(png_sizeof(png_info))
+ * and png_info_init() so that applications that want to use a shared
+ * libpng don't have to be recompiled if png_info changes size.
+ */
+png_infop PNGAPI
+png_create_info_struct(png_structp png_ptr)
+{
+ png_infop info_ptr;
+
+ png_debug(1, "in png_create_info_struct\n");
+ if(png_ptr == NULL) return (NULL);
+#ifdef PNG_USER_MEM_SUPPORTED
+ info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
+ png_ptr->malloc_fn, png_ptr->mem_ptr);
+#else
+ info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
+#endif
+ if (info_ptr != NULL)
+ png_info_init_3(&info_ptr, png_sizeof(png_info));
+
+ return (info_ptr);
+}
+
+/* This function frees the memory associated with a single info struct.
+ * Normally, one would use either png_destroy_read_struct() or
+ * png_destroy_write_struct() to free an info struct, but this may be
+ * useful for some applications.
+ */
+void PNGAPI
+png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr)
+{
+ png_infop info_ptr = NULL;
+ if(png_ptr == NULL) return;
+
+ png_debug(1, "in png_destroy_info_struct\n");
+ if (info_ptr_ptr != NULL)
+ info_ptr = *info_ptr_ptr;
+
+ if (info_ptr != NULL)
+ {
+ png_info_destroy(png_ptr, info_ptr);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2((png_voidp)info_ptr, png_ptr->free_fn,
+ png_ptr->mem_ptr);
+#else
+ png_destroy_struct((png_voidp)info_ptr);
+#endif
+ *info_ptr_ptr = NULL;
+ }
+}
+
+/* Initialize the info structure. This is now an internal function (0.89)
+ * and applications using it are urged to use png_create_info_struct()
+ * instead.
+ */
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+#undef png_info_init
+void PNGAPI
+png_info_init(png_infop info_ptr)
+{
+ /* We only come here via pre-1.0.12-compiled applications */
+ png_info_init_3(&info_ptr, 0);
+}
+#endif
+
+void PNGAPI
+png_info_init_3(png_infopp ptr_ptr, png_size_t png_info_struct_size)
+{
+ png_infop info_ptr = *ptr_ptr;
+
+ if(info_ptr == NULL) return;
+
+ png_debug(1, "in png_info_init_3\n");
+
+ if(png_sizeof(png_info) > png_info_struct_size)
+ {
+ png_destroy_struct(info_ptr);
+ info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
+ *ptr_ptr = info_ptr;
+ }
+
+ /* set everything to 0 */
+ png_memset(info_ptr, 0, png_sizeof (png_info));
+}
+
+#ifdef PNG_FREE_ME_SUPPORTED
+void PNGAPI
+png_data_freer(png_structp png_ptr, png_infop info_ptr,
+ int freer, png_uint_32 mask)
+{
+ png_debug(1, "in png_data_freer\n");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+ if(freer == PNG_DESTROY_WILL_FREE_DATA)
+ info_ptr->free_me |= mask;
+ else if(freer == PNG_USER_WILL_FREE_DATA)
+ info_ptr->free_me &= ~mask;
+ else
+ png_warning(png_ptr,
+ "Unknown freer parameter in png_data_freer.");
+}
+#endif
+
+void PNGAPI
+png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask,
+ int num)
+{
+ png_debug(1, "in png_free_data\n");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+#if defined(PNG_TEXT_SUPPORTED)
+/* free text item num or (if num == -1) all text items */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_TEXT) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_TEXT)
+#endif
+{
+ if (num != -1)
+ {
+ if (info_ptr->text && info_ptr->text[num].key)
+ {
+ png_free(png_ptr, info_ptr->text[num].key);
+ info_ptr->text[num].key = NULL;
+ }
+ }
+ else
+ {
+ int i;
+ for (i = 0; i < info_ptr->num_text; i++)
+ png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, i);
+ png_free(png_ptr, info_ptr->text);
+ info_ptr->text = NULL;
+ info_ptr->num_text=0;
+ }
+}
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+/* free any tRNS entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_TRNS) & info_ptr->free_me)
+#else
+if ((mask & PNG_FREE_TRNS) && (png_ptr->flags & PNG_FLAG_FREE_TRNS))
+#endif
+{
+ png_free(png_ptr, info_ptr->trans);
+ info_ptr->valid &= ~PNG_INFO_tRNS;
+#ifndef PNG_FREE_ME_SUPPORTED
+ png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
+#endif
+ info_ptr->trans = NULL;
+}
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+/* free any sCAL entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_SCAL) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_SCAL)
+#endif
+{
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
+ png_free(png_ptr, info_ptr->scal_s_width);
+ png_free(png_ptr, info_ptr->scal_s_height);
+ info_ptr->scal_s_width = NULL;
+ info_ptr->scal_s_height = NULL;
+#endif
+ info_ptr->valid &= ~PNG_INFO_sCAL;
+}
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+/* free any pCAL entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_PCAL) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_PCAL)
+#endif
+{
+ png_free(png_ptr, info_ptr->pcal_purpose);
+ png_free(png_ptr, info_ptr->pcal_units);
+ info_ptr->pcal_purpose = NULL;
+ info_ptr->pcal_units = NULL;
+ if (info_ptr->pcal_params != NULL)
+ {
+ int i;
+ for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
+ {
+ png_free(png_ptr, info_ptr->pcal_params[i]);
+ info_ptr->pcal_params[i]=NULL;
+ }
+ png_free(png_ptr, info_ptr->pcal_params);
+ info_ptr->pcal_params = NULL;
+ }
+ info_ptr->valid &= ~PNG_INFO_pCAL;
+}
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+/* free any iCCP entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_ICCP) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_ICCP)
+#endif
+{
+ png_free(png_ptr, info_ptr->iccp_name);
+ png_free(png_ptr, info_ptr->iccp_profile);
+ info_ptr->iccp_name = NULL;
+ info_ptr->iccp_profile = NULL;
+ info_ptr->valid &= ~PNG_INFO_iCCP;
+}
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+/* free a given sPLT entry, or (if num == -1) all sPLT entries */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_SPLT) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_SPLT)
+#endif
+{
+ if (num != -1)
+ {
+ if(info_ptr->splt_palettes)
+ {
+ png_free(png_ptr, info_ptr->splt_palettes[num].name);
+ png_free(png_ptr, info_ptr->splt_palettes[num].entries);
+ info_ptr->splt_palettes[num].name = NULL;
+ info_ptr->splt_palettes[num].entries = NULL;
+ }
+ }
+ else
+ {
+ if(info_ptr->splt_palettes_num)
+ {
+ int i;
+ for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
+ png_free_data(png_ptr, info_ptr, PNG_FREE_SPLT, i);
+
+ png_free(png_ptr, info_ptr->splt_palettes);
+ info_ptr->splt_palettes = NULL;
+ info_ptr->splt_palettes_num = 0;
+ }
+ info_ptr->valid &= ~PNG_INFO_sPLT;
+ }
+}
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+ if(png_ptr->unknown_chunk.data)
+ {
+ png_free(png_ptr, png_ptr->unknown_chunk.data);
+ png_ptr->unknown_chunk.data = NULL;
+ }
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_UNKN) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_UNKN)
+#endif
+{
+ if (num != -1)
+ {
+ if(info_ptr->unknown_chunks)
+ {
+ png_free(png_ptr, info_ptr->unknown_chunks[num].data);
+ info_ptr->unknown_chunks[num].data = NULL;
+ }
+ }
+ else
+ {
+ int i;
+
+ if(info_ptr->unknown_chunks_num)
+ {
+ for (i = 0; i < (int)info_ptr->unknown_chunks_num; i++)
+ png_free_data(png_ptr, info_ptr, PNG_FREE_UNKN, i);
+
+ png_free(png_ptr, info_ptr->unknown_chunks);
+ info_ptr->unknown_chunks = NULL;
+ info_ptr->unknown_chunks_num = 0;
+ }
+ }
+}
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+/* free any hIST entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_HIST) & info_ptr->free_me)
+#else
+if ((mask & PNG_FREE_HIST) && (png_ptr->flags & PNG_FLAG_FREE_HIST))
+#endif
+{
+ png_free(png_ptr, info_ptr->hist);
+ info_ptr->hist = NULL;
+ info_ptr->valid &= ~PNG_INFO_hIST;
+#ifndef PNG_FREE_ME_SUPPORTED
+ png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
+#endif
+}
+#endif
+
+/* free any PLTE entry that was internally allocated */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_PLTE) & info_ptr->free_me)
+#else
+if ((mask & PNG_FREE_PLTE) && (png_ptr->flags & PNG_FLAG_FREE_PLTE))
+#endif
+{
+ png_zfree(png_ptr, info_ptr->palette);
+ info_ptr->palette = NULL;
+ info_ptr->valid &= ~PNG_INFO_PLTE;
+#ifndef PNG_FREE_ME_SUPPORTED
+ png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
+#endif
+ info_ptr->num_palette = 0;
+}
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+/* free any image bits attached to the info structure */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_ROWS) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_ROWS)
+#endif
+{
+ if(info_ptr->row_pointers)
+ {
+ int row;
+ for (row = 0; row < (int)info_ptr->height; row++)
+ {
+ png_free(png_ptr, info_ptr->row_pointers[row]);
+ info_ptr->row_pointers[row]=NULL;
+ }
+ png_free(png_ptr, info_ptr->row_pointers);
+ info_ptr->row_pointers=NULL;
+ }
+ info_ptr->valid &= ~PNG_INFO_IDAT;
+}
+#endif
+
+#ifdef PNG_FREE_ME_SUPPORTED
+ if(num == -1)
+ info_ptr->free_me &= ~mask;
+ else
+ info_ptr->free_me &= ~(mask & ~PNG_FREE_MUL);
+#endif
+}
+
+/* This is an internal routine to free any memory that the info struct is
+ * pointing to before re-using it or freeing the struct itself. Recall
+ * that png_free() checks for NULL pointers for us.
+ */
+void /* PRIVATE */
+png_info_destroy(png_structp png_ptr, png_infop info_ptr)
+{
+ png_debug(1, "in png_info_destroy\n");
+
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+ if (png_ptr->num_chunk_list)
+ {
+ png_free(png_ptr, png_ptr->chunk_list);
+ png_ptr->chunk_list=NULL;
+ png_ptr->num_chunk_list=0;
+ }
+#endif
+
+ png_info_init_3(&info_ptr, png_sizeof(png_info));
+}
+#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
+
+/* This function returns a pointer to the io_ptr associated with the user
+ * functions. The application should free any memory associated with this
+ * pointer before png_write_destroy() or png_read_destroy() are called.
+ */
+png_voidp PNGAPI
+png_get_io_ptr(png_structp png_ptr)
+{
+ if(png_ptr == NULL) return (NULL);
+ return (png_ptr->io_ptr);
+}
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+#if !defined(PNG_NO_STDIO)
+/* Initialize the default input/output functions for the PNG file. If you
+ * use your own read or write routines, you can call either png_set_read_fn()
+ * or png_set_write_fn() instead of png_init_io(). If you have defined
+ * PNG_NO_STDIO, you must use a function of your own because "FILE *" isn't
+ * necessarily available.
+ */
+void PNGAPI
+png_init_io(png_structp png_ptr, png_FILE_p fp)
+{
+ png_debug(1, "in png_init_io\n");
+ if(png_ptr == NULL) return;
+ png_ptr->io_ptr = (png_voidp)fp;
+}
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+/* Convert the supplied time into an RFC 1123 string suitable for use in
+ * a "Creation Time" or other text-based time string.
+ */
+png_charp PNGAPI
+png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime)
+{
+ static PNG_CONST char short_months[12][4] =
+ {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
+ "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
+
+ if(png_ptr == NULL) return (NULL);
+ if (png_ptr->time_buffer == NULL)
+ {
+ png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, (png_uint_32)(29*
+ png_sizeof(char)));
+ }
+
+#if defined(_WIN32_WCE)
+ {
+ wchar_t time_buf[29];
+ wsprintf(time_buf, TEXT("%d %S %d %02d:%02d:%02d +0000"),
+ ptime->day % 32, short_months[(ptime->month - 1) % 12],
+ ptime->year, ptime->hour % 24, ptime->minute % 60,
+ ptime->second % 61);
+ WideCharToMultiByte(CP_ACP, 0, time_buf, -1, png_ptr->time_buffer, 29,
+ NULL, NULL);
+ }
+#else
+#ifdef USE_FAR_KEYWORD
+ {
+ char near_time_buf[29];
+ png_snprintf6(near_time_buf,29,"%d %s %d %02d:%02d:%02d +0000",
+ ptime->day % 32, short_months[(ptime->month - 1) % 12],
+ ptime->year, ptime->hour % 24, ptime->minute % 60,
+ ptime->second % 61);
+ png_memcpy(png_ptr->time_buffer, near_time_buf,
+ 29*png_sizeof(char));
+ }
+#else
+ png_snprintf6(png_ptr->time_buffer,29,"%d %s %d %02d:%02d:%02d +0000",
+ ptime->day % 32, short_months[(ptime->month - 1) % 12],
+ ptime->year, ptime->hour % 24, ptime->minute % 60,
+ ptime->second % 61);
+#endif
+#endif /* _WIN32_WCE */
+ return ((png_charp)png_ptr->time_buffer);
+}
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+
+#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
+
+png_charp PNGAPI
+png_get_copyright(png_structp png_ptr)
+{
+ png_ptr = png_ptr; /* silence compiler warning about unused png_ptr */
+ return ((png_charp) "\n libpng version 1.2.22 - October 13, 2007\n\
+ Copyright (c) 1998-2007 Glenn Randers-Pehrson\n\
+ Copyright (c) 1996-1997 Andreas Dilger\n\
+ Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.\n");
+}
+
+/* The following return the library version as a short string in the
+ * format 1.0.0 through 99.99.99zz. To get the version of *.h files
+ * used with your application, print out PNG_LIBPNG_VER_STRING, which
+ * is defined in png.h.
+ * Note: now there is no difference between png_get_libpng_ver() and
+ * png_get_header_ver(). Due to the version_nn_nn_nn typedef guard,
+ * it is guaranteed that png.c uses the correct version of png.h.
+ */
+png_charp PNGAPI
+png_get_libpng_ver(png_structp png_ptr)
+{
+ /* Version of *.c files used when building libpng */
+ png_ptr = png_ptr; /* silence compiler warning about unused png_ptr */
+ return ((png_charp) PNG_LIBPNG_VER_STRING);
+}
+
+png_charp PNGAPI
+png_get_header_ver(png_structp png_ptr)
+{
+ /* Version of *.h files used when building libpng */
+ png_ptr = png_ptr; /* silence compiler warning about unused png_ptr */
+ return ((png_charp) PNG_LIBPNG_VER_STRING);
+}
+
+png_charp PNGAPI
+png_get_header_version(png_structp png_ptr)
+{
+ /* Returns longer string containing both version and date */
+ png_ptr = png_ptr; /* silence compiler warning about unused png_ptr */
+ return ((png_charp) PNG_HEADER_VERSION_STRING
+#ifndef PNG_READ_SUPPORTED
+ " (NO READ SUPPORT)"
+#endif
+ "\n");
+}
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+int PNGAPI
+png_handle_as_unknown(png_structp png_ptr, png_bytep chunk_name)
+{
+ /* check chunk_name and return "keep" value if it's on the list, else 0 */
+ int i;
+ png_bytep p;
+ if(png_ptr == NULL || chunk_name == NULL || png_ptr->num_chunk_list<=0)
+ return 0;
+ p=png_ptr->chunk_list+png_ptr->num_chunk_list*5-5;
+ for (i = png_ptr->num_chunk_list; i; i--, p-=5)
+ if (!png_memcmp(chunk_name, p, 4))
+ return ((int)*(p+4));
+ return 0;
+}
+#endif
+
+/* This function, added to libpng-1.0.6g, is untested. */
+int PNGAPI
+png_reset_zstream(png_structp png_ptr)
+{
+ if (png_ptr == NULL) return Z_STREAM_ERROR;
+ return (inflateReset(&png_ptr->zstream));
+}
+#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
+
+/* This function was added to libpng-1.0.7 */
+png_uint_32 PNGAPI
+png_access_version_number(void)
+{
+ /* Version of *.c files used when building libpng */
+ return((png_uint_32) PNG_LIBPNG_VER);
+}
+
+
+#if defined(PNG_READ_SUPPORTED) && defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+#if !defined(PNG_1_0_X)
+/* this function was added to libpng 1.2.0 */
+int PNGAPI
+png_mmx_support(void)
+{
+ /* obsolete, to be removed from libpng-1.4.0 */
+ return -1;
+}
+#endif /* PNG_1_0_X */
+#endif /* PNG_READ_SUPPORTED && PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+#ifdef PNG_SIZE_T
+/* Added at libpng version 1.2.6 */
+ PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
+png_size_t PNGAPI
+png_convert_size(size_t size)
+{
+ if (size > (png_size_t)-1)
+ PNG_ABORT(); /* We haven't got access to png_ptr, so no png_error() */
+ return ((png_size_t)size);
+}
+#endif /* PNG_SIZE_T */
+#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
diff --git a/src/libpng/png.h b/src/libpng/png.h
new file mode 100644
index 0000000..81af541
--- /dev/null
+++ b/src/libpng/png.h
@@ -0,0 +1,3540 @@
+
+/* png.h - header file for PNG reference library
+ *
+ * libpng version 1.2.22 - October 13, 2007
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * Authors and maintainers:
+ * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
+ * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
+ * libpng versions 0.97, January 1998, through 1.2.22 - October 13, 2007: Glenn
+ * See also "Contributing Authors", below.
+ *
+ * Note about libpng version numbers:
+ *
+ * Due to various miscommunications, unforeseen code incompatibilities
+ * and occasional factors outside the authors' control, version numbering
+ * on the library has not always been consistent and straightforward.
+ * The following table summarizes matters since version 0.89c, which was
+ * the first widely used release:
+ *
+ * source png.h png.h shared-lib
+ * version string int version
+ * ------- ------ ----- ----------
+ * 0.89c "1.0 beta 3" 0.89 89 1.0.89
+ * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]
+ * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]
+ * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]
+ * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]
+ * 0.97c 0.97 97 2.0.97
+ * 0.98 0.98 98 2.0.98
+ * 0.99 0.99 98 2.0.99
+ * 0.99a-m 0.99 99 2.0.99
+ * 1.00 1.00 100 2.1.0 [100 should be 10000]
+ * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]
+ * 1.0.1 png.h string is 10001 2.1.0
+ * 1.0.1a-e identical to the 10002 from here on, the shared library
+ * 1.0.2 source version) 10002 is 2.V where V is the source code
+ * 1.0.2a-b 10003 version, except as noted.
+ * 1.0.3 10003
+ * 1.0.3a-d 10004
+ * 1.0.4 10004
+ * 1.0.4a-f 10005
+ * 1.0.5 (+ 2 patches) 10005
+ * 1.0.5a-d 10006
+ * 1.0.5e-r 10100 (not source compatible)
+ * 1.0.5s-v 10006 (not binary compatible)
+ * 1.0.6 (+ 3 patches) 10006 (still binary incompatible)
+ * 1.0.6d-f 10007 (still binary incompatible)
+ * 1.0.6g 10007
+ * 1.0.6h 10007 10.6h (testing xy.z so-numbering)
+ * 1.0.6i 10007 10.6i
+ * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)
+ * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)
+ * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)
+ * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)
+ * 1.0.7 1 10007 (still compatible)
+ * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4
+ * 1.0.8rc1 1 10008 2.1.0.8rc1
+ * 1.0.8 1 10008 2.1.0.8
+ * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6
+ * 1.0.9rc1 1 10009 2.1.0.9rc1
+ * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10
+ * 1.0.9rc2 1 10009 2.1.0.9rc2
+ * 1.0.9 1 10009 2.1.0.9
+ * 1.0.10beta1 1 10010 2.1.0.10beta1
+ * 1.0.10rc1 1 10010 2.1.0.10rc1
+ * 1.0.10 1 10010 2.1.0.10
+ * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3
+ * 1.0.11rc1 1 10011 2.1.0.11rc1
+ * 1.0.11 1 10011 2.1.0.11
+ * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2
+ * 1.0.12rc1 2 10012 2.1.0.12rc1
+ * 1.0.12 2 10012 2.1.0.12
+ * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned)
+ * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2
+ * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5
+ * 1.2.0rc1 3 10200 3.1.2.0rc1
+ * 1.2.0 3 10200 3.1.2.0
+ * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4
+ * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2
+ * 1.2.1 3 10201 3.1.2.1
+ * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6
+ * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1
+ * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1
+ * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1
+ * 1.0.13 10 10013 10.so.0.1.0.13
+ * 1.2.2 12 10202 12.so.0.1.2.2
+ * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6
+ * 1.2.3 12 10203 12.so.0.1.2.3
+ * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3
+ * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1
+ * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1
+ * 1.0.14 10 10014 10.so.0.1.0.14
+ * 1.2.4 13 10204 12.so.0.1.2.4
+ * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2
+ * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3
+ * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3
+ * 1.0.15 10 10015 10.so.0.1.0.15
+ * 1.2.5 13 10205 12.so.0.1.2.5
+ * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4
+ * 1.0.16 10 10016 10.so.0.1.0.16
+ * 1.2.6 13 10206 12.so.0.1.2.6
+ * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2
+ * 1.0.17rc1 10 10017 10.so.0.1.0.17rc1
+ * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1
+ * 1.0.17 10 10017 10.so.0.1.0.17
+ * 1.2.7 13 10207 12.so.0.1.2.7
+ * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5
+ * 1.0.18rc1-5 10 10018 10.so.0.1.0.18rc1-5
+ * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5
+ * 1.0.18 10 10018 10.so.0.1.0.18
+ * 1.2.8 13 10208 12.so.0.1.2.8
+ * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3
+ * 1.2.9beta4-11 13 10209 12.so.0.9[.0]
+ * 1.2.9rc1 13 10209 12.so.0.9[.0]
+ * 1.2.9 13 10209 12.so.0.9[.0]
+ * 1.2.10beta1-8 13 10210 12.so.0.10[.0]
+ * 1.2.10rc1-3 13 10210 12.so.0.10[.0]
+ * 1.2.10 13 10210 12.so.0.10[.0]
+ * 1.2.11beta1-4 13 10211 12.so.0.11[.0]
+ * 1.0.19rc1-5 10 10019 10.so.0.19[.0]
+ * 1.2.11rc1-5 13 10211 12.so.0.11[.0]
+ * 1.0.19 10 10019 10.so.0.19[.0]
+ * 1.2.11 13 10211 12.so.0.11[.0]
+ * 1.0.20 10 10020 10.so.0.20[.0]
+ * 1.2.12 13 10212 12.so.0.12[.0]
+ * 1.2.13beta1 13 10213 12.so.0.13[.0]
+ * 1.0.21 10 10021 10.so.0.21[.0]
+ * 1.2.13 13 10213 12.so.0.13[.0]
+ * 1.2.14beta1-2 13 10214 12.so.0.14[.0]
+ * 1.0.22rc1 10 10022 10.so.0.22[.0]
+ * 1.2.14rc1 13 10214 12.so.0.14[.0]
+ * 1.0.22 10 10022 10.so.0.22[.0]
+ * 1.2.14 13 10214 12.so.0.14[.0]
+ * 1.2.15beta1-6 13 10215 12.so.0.15[.0]
+ * 1.0.23rc1-5 10 10023 10.so.0.23[.0]
+ * 1.2.15rc1-5 13 10215 12.so.0.15[.0]
+ * 1.0.23 10 10023 10.so.0.23[.0]
+ * 1.2.15 13 10215 12.so.0.15[.0]
+ * 1.2.16beta1-2 13 10216 12.so.0.16[.0]
+ * 1.2.16rc1 13 10216 12.so.0.16[.0]
+ * 1.0.24 10 10024 10.so.0.24[.0]
+ * 1.2.16 13 10216 12.so.0.16[.0]
+ * 1.2.17beta1-2 13 10217 12.so.0.17[.0]
+ * 1.0.25rc1 10 10025 10.so.0.25[.0]
+ * 1.2.17rc1-3 13 10217 12.so.0.17[.0]
+ * 1.0.25 10 10025 10.so.0.25[.0]
+ * 1.2.17 13 10217 12.so.0.17[.0]
+ * 1.0.26 10 10026 10.so.0.26[.0]
+ * 1.2.18 13 10218 12.so.0.18[.0]
+ * 1.2.19beta1-31 13 10219 12.so.0.19[.0]
+ * 1.0.27rc1-6 10 10027 10.so.0.27[.0]
+ * 1.2.19rc1-6 13 10219 12.so.0.19[.0]
+ * 1.0.27 10 10027 10.so.0.27[.0]
+ * 1.2.19 13 10219 12.so.0.19[.0]
+ * 1.2.20beta01-04 13 10220 12.so.0.20[.0]
+ * 1.0.28rc1-6 10 10028 10.so.0.28[.0]
+ * 1.2.20rc1-6 13 10220 12.so.0.20[.0]
+ * 1.0.28 10 10028 10.so.0.28[.0]
+ * 1.2.20 13 10220 12.so.0.20[.0]
+ * 1.2.21beta1-2 13 10221 12.so.0.21[.0]
+ * 1.2.21rc1-3 13 10221 12.so.0.21[.0]
+ * 1.0.29 10 10029 10.so.0.29[.0]
+ * 1.2.21 13 10221 12.so.0.21[.0]
+ * 1.2.22beta1-4 13 10222 12.so.0.22[.0]
+ * 1.0.30rc1 10 10030 10.so.0.30[.0]
+ * 1.2.22rc1 13 10222 12.so.0.22[.0]
+ * 1.0.30 10 10030 10.so.0.30[.0]
+ * 1.2.22 13 10222 12.so.0.22[.0]
+ *
+ * Henceforth the source version will match the shared-library major
+ * and minor numbers; the shared-library major version number will be
+ * used for changes in backward compatibility, as it is intended. The
+ * PNG_LIBPNG_VER macro, which is not used within libpng but is available
+ * for applications, is an unsigned integer of the form xyyzz corresponding
+ * to the source version x.y.z (leading zeros in y and z). Beta versions
+ * were given the previous public release number plus a letter, until
+ * version 1.0.6j; from then on they were given the upcoming public
+ * release number plus "betaNN" or "rcN".
+ *
+ * Binary incompatibility exists only when applications make direct access
+ * to the info_ptr or png_ptr members through png.h, and the compiled
+ * application is loaded with a different version of the library.
+ *
+ * DLLNUM will change each time there are forward or backward changes
+ * in binary compatibility (e.g., when a new feature is added).
+ *
+ * See libpng.txt or libpng.3 for more information. The PNG specification
+ * is available as a W3C Recommendation and as an ISO Specification,
+ * <http://www.w3.org/TR/2003/REC-PNG-20031110/
+ */
+
+/*
+ * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
+ *
+ * If you modify libpng you may insert additional notices immediately following
+ * this sentence.
+ *
+ * libpng versions 1.2.6, August 15, 2004, through 1.2.22, October 13, 2007, are
+ * Copyright (c) 2004, 2006-2007 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.2.5
+ * with the following individual added to the list of Contributing Authors:
+ *
+ * Cosmin Truta
+ *
+ * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
+ * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.0.6
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ * Simon-Pierre Cadieux
+ * Eric S. Raymond
+ * Gilles Vollant
+ *
+ * and with the following additions to the disclaimer:
+ *
+ * There is no warranty against interference with your enjoyment of the
+ * library or against infringement. There is no warranty that our
+ * efforts or the library will fulfill any of your particular purposes
+ * or needs. This library is provided with all faults, and the entire
+ * risk of satisfactory quality, performance, accuracy, and effort is with
+ * the user.
+ *
+ * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
+ * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-0.96,
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ * Tom Lane
+ * Glenn Randers-Pehrson
+ * Willem van Schaik
+ *
+ * libpng versions 0.89, June 1996, through 0.96, May 1997, are
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Distributed according to the same disclaimer and license as libpng-0.88,
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ * John Bowler
+ * Kevin Bracey
+ * Sam Bushell
+ * Magnus Holmgren
+ * Greg Roelofs
+ * Tom Tanner
+ *
+ * libpng versions 0.5, May 1995, through 0.88, January 1996, are
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ *
+ * For the purposes of this copyright and license, "Contributing Authors"
+ * is defined as the following set of individuals:
+ *
+ * Andreas Dilger
+ * Dave Martindale
+ * Guy Eric Schalnat
+ * Paul Schmidt
+ * Tim Wegner
+ *
+ * The PNG Reference Library is supplied "AS IS". The Contributing Authors
+ * and Group 42, Inc. disclaim all warranties, expressed or implied,
+ * including, without limitation, the warranties of merchantability and of
+ * fitness for any purpose. The Contributing Authors and Group 42, Inc.
+ * assume no liability for direct, indirect, incidental, special, exemplary,
+ * or consequential damages, which may result from the use of the PNG
+ * Reference Library, even if advised of the possibility of such damage.
+ *
+ * Permission is hereby granted to use, copy, modify, and distribute this
+ * source code, or portions hereof, for any purpose, without fee, subject
+ * to the following restrictions:
+ *
+ * 1. The origin of this source code must not be misrepresented.
+ *
+ * 2. Altered versions must be plainly marked as such and
+ * must not be misrepresented as being the original source.
+ *
+ * 3. This Copyright notice may not be removed or altered from
+ * any source or altered source distribution.
+ *
+ * The Contributing Authors and Group 42, Inc. specifically permit, without
+ * fee, and encourage the use of this source code as a component to
+ * supporting the PNG file format in commercial products. If you use this
+ * source code in a product, acknowledgment is not required but would be
+ * appreciated.
+ */
+
+/*
+ * A "png_get_copyright" function is available, for convenient use in "about"
+ * boxes and the like:
+ *
+ * printf("%s",png_get_copyright(NULL));
+ *
+ * Also, the PNG logo (in PNG format, of course) is supplied in the
+ * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+ */
+
+/*
+ * Libpng is OSI Certified Open Source Software. OSI Certified is a
+ * certification mark of the Open Source Initiative.
+ */
+
+/*
+ * The contributing authors would like to thank all those who helped
+ * with testing, bug fixes, and patience. This wouldn't have been
+ * possible without all of you.
+ *
+ * Thanks to Frank J. T. Wojcik for helping with the documentation.
+ */
+
+/*
+ * Y2K compliance in libpng:
+ * =========================
+ *
+ * October 13, 2007
+ *
+ * Since the PNG Development group is an ad-hoc body, we can't make
+ * an official declaration.
+ *
+ * This is your unofficial assurance that libpng from version 0.71 and
+ * upward through 1.2.22 are Y2K compliant. It is my belief that earlier
+ * versions were also Y2K compliant.
+ *
+ * Libpng only has three year fields. One is a 2-byte unsigned integer
+ * that will hold years up to 65535. The other two hold the date in text
+ * format, and will hold years up to 9999.
+ *
+ * The integer is
+ * "png_uint_16 year" in png_time_struct.
+ *
+ * The strings are
+ * "png_charp time_buffer" in png_struct and
+ * "near_time_buffer", which is a local character string in png.c.
+ *
+ * There are seven time-related functions:
+ * png.c: png_convert_to_rfc_1123() in png.c
+ * (formerly png_convert_to_rfc_1152() in error)
+ * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
+ * png_convert_from_time_t() in pngwrite.c
+ * png_get_tIME() in pngget.c
+ * png_handle_tIME() in pngrutil.c, called in pngread.c
+ * png_set_tIME() in pngset.c
+ * png_write_tIME() in pngwutil.c, called in pngwrite.c
+ *
+ * All handle dates properly in a Y2K environment. The
+ * png_convert_from_time_t() function calls gmtime() to convert from system
+ * clock time, which returns (year - 1900), which we properly convert to
+ * the full 4-digit year. There is a possibility that applications using
+ * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
+ * function, or that they are incorrectly passing only a 2-digit year
+ * instead of "year - 1900" into the png_convert_from_struct_tm() function,
+ * but this is not under our control. The libpng documentation has always
+ * stated that it works with 4-digit years, and the APIs have been
+ * documented as such.
+ *
+ * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
+ * integer to hold the year, and can hold years as large as 65535.
+ *
+ * zlib, upon which libpng depends, is also Y2K compliant. It contains
+ * no date-related code.
+ *
+ * Glenn Randers-Pehrson
+ * libpng maintainer
+ * PNG Development Group
+ */
+
+#ifndef PNG_H
+#define PNG_H
+
+/* This is not the place to learn how to use libpng. The file libpng.txt
+ * describes how to use libpng, and the file example.c summarizes it
+ * with some code on which to build. This file is useful for looking
+ * at the actual function definitions and structure components.
+ */
+
+/* Version information for png.h - this should match the version in png.c */
+#define PNG_LIBPNG_VER_STRING "1.2.22"
+#define PNG_HEADER_VERSION_STRING \
+ " libpng version 1.2.22 - October 13, 2007\n"
+
+#define PNG_LIBPNG_VER_SONUM 0
+#define PNG_LIBPNG_VER_DLLNUM 13
+
+/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
+#define PNG_LIBPNG_VER_MAJOR 1
+#define PNG_LIBPNG_VER_MINOR 2
+#define PNG_LIBPNG_VER_RELEASE 22
+/* This should match the numeric part of the final component of
+ * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
+
+#define PNG_LIBPNG_VER_BUILD 0
+
+/* Release Status */
+#define PNG_LIBPNG_BUILD_ALPHA 1
+#define PNG_LIBPNG_BUILD_BETA 2
+#define PNG_LIBPNG_BUILD_RC 3
+#define PNG_LIBPNG_BUILD_STABLE 4
+#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
+
+/* Release-Specific Flags */
+#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with
+ PNG_LIBPNG_BUILD_STABLE only */
+#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
+ PNG_LIBPNG_BUILD_SPECIAL */
+#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
+ PNG_LIBPNG_BUILD_PRIVATE */
+
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
+
+/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
+ * We must not include leading zeros.
+ * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
+ * version 1.0.0 was mis-numbered 100 instead of 10000). From
+ * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release */
+#define PNG_LIBPNG_VER 10222 /* 1.2.22 */
+
+#ifndef PNG_VERSION_INFO_ONLY
+/* include the compression library's header */
+#include "zlib.h"
+#endif
+
+/* include all user configurable info, including optional assembler routines */
+#include "pngconf.h"
+
+/*
+ * Added at libpng-1.2.8 */
+/* Ref MSDN: Private as priority over Special
+ * VS_FF_PRIVATEBUILD File *was not* built using standard release
+ * procedures. If this value is given, the StringFileInfo block must
+ * contain a PrivateBuild string.
+ *
+ * VS_FF_SPECIALBUILD File *was* built by the original company using
+ * standard release procedures but is a variation of the standard
+ * file of the same version number. If this value is given, the
+ * StringFileInfo block must contain a SpecialBuild string.
+ */
+
+#if defined(PNG_USER_PRIVATEBUILD)
+# define PNG_LIBPNG_BUILD_TYPE \
+ (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
+#else
+# if defined(PNG_LIBPNG_SPECIALBUILD)
+# define PNG_LIBPNG_BUILD_TYPE \
+ (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
+# else
+# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
+# endif
+#endif
+
+#ifndef PNG_VERSION_INFO_ONLY
+
+/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/* This file is arranged in several sections. The first section contains
+ * structure and type definitions. The second section contains the external
+ * library functions, while the third has the internal library functions,
+ * which applications aren't expected to use directly.
+ */
+
+#ifndef PNG_NO_TYPECAST_NULL
+#define int_p_NULL (int *)NULL
+#define png_bytep_NULL (png_bytep)NULL
+#define png_bytepp_NULL (png_bytepp)NULL
+#define png_doublep_NULL (png_doublep)NULL
+#define png_error_ptr_NULL (png_error_ptr)NULL
+#define png_flush_ptr_NULL (png_flush_ptr)NULL
+#define png_free_ptr_NULL (png_free_ptr)NULL
+#define png_infopp_NULL (png_infopp)NULL
+#define png_malloc_ptr_NULL (png_malloc_ptr)NULL
+#define png_read_status_ptr_NULL (png_read_status_ptr)NULL
+#define png_rw_ptr_NULL (png_rw_ptr)NULL
+#define png_structp_NULL (png_structp)NULL
+#define png_uint_16p_NULL (png_uint_16p)NULL
+#define png_voidp_NULL (png_voidp)NULL
+#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
+#else
+#define int_p_NULL NULL
+#define png_bytep_NULL NULL
+#define png_bytepp_NULL NULL
+#define png_doublep_NULL NULL
+#define png_error_ptr_NULL NULL
+#define png_flush_ptr_NULL NULL
+#define png_free_ptr_NULL NULL
+#define png_infopp_NULL NULL
+#define png_malloc_ptr_NULL NULL
+#define png_read_status_ptr_NULL NULL
+#define png_rw_ptr_NULL NULL
+#define png_structp_NULL NULL
+#define png_uint_16p_NULL NULL
+#define png_voidp_NULL NULL
+#define png_write_status_ptr_NULL NULL
+#endif
+
+/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
+#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
+/* Version information for C files, stored in png.c. This had better match
+ * the version above.
+ */
+#ifdef PNG_USE_GLOBAL_ARRAYS
+PNG_EXPORT_VAR (PNG_CONST char) png_libpng_ver[18];
+ /* need room for 99.99.99beta99z */
+#else
+#define png_libpng_ver png_get_header_ver(NULL)
+#endif
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+/* This was removed in version 1.0.5c */
+/* Structures to facilitate easy interlacing. See png.c for more details */
+PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_start[7];
+PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_inc[7];
+PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_ystart[7];
+PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_yinc[7];
+PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_mask[7];
+PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_dsp_mask[7];
+/* This isn't currently used. If you need it, see png.c for more details.
+PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_height[7];
+*/
+#endif
+
+#endif /* PNG_NO_EXTERN */
+
+/* Three color definitions. The order of the red, green, and blue, (and the
+ * exact size) is not important, although the size of the fields need to
+ * be png_byte or png_uint_16 (as defined below).
+ */
+typedef struct png_color_struct
+{
+ png_byte red;
+ png_byte green;
+ png_byte blue;
+} png_color;
+typedef png_color FAR * png_colorp;
+typedef png_color FAR * FAR * png_colorpp;
+
+typedef struct png_color_16_struct
+{
+ png_byte index; /* used for palette files */
+ png_uint_16 red; /* for use in red green blue files */
+ png_uint_16 green;
+ png_uint_16 blue;
+ png_uint_16 gray; /* for use in grayscale files */
+} png_color_16;
+typedef png_color_16 FAR * png_color_16p;
+typedef png_color_16 FAR * FAR * png_color_16pp;
+
+typedef struct png_color_8_struct
+{
+ png_byte red; /* for use in red green blue files */
+ png_byte green;
+ png_byte blue;
+ png_byte gray; /* for use in grayscale files */
+ png_byte alpha; /* for alpha channel files */
+} png_color_8;
+typedef png_color_8 FAR * png_color_8p;
+typedef png_color_8 FAR * FAR * png_color_8pp;
+
+/*
+ * The following two structures are used for the in-core representation
+ * of sPLT chunks.
+ */
+typedef struct png_sPLT_entry_struct
+{
+ png_uint_16 red;
+ png_uint_16 green;
+ png_uint_16 blue;
+ png_uint_16 alpha;
+ png_uint_16 frequency;
+} png_sPLT_entry;
+typedef png_sPLT_entry FAR * png_sPLT_entryp;
+typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
+
+/* When the depth of the sPLT palette is 8 bits, the color and alpha samples
+ * occupy the LSB of their respective members, and the MSB of each member
+ * is zero-filled. The frequency member always occupies the full 16 bits.
+ */
+
+typedef struct png_sPLT_struct
+{
+ png_charp name; /* palette name */
+ png_byte depth; /* depth of palette samples */
+ png_sPLT_entryp entries; /* palette entries */
+ png_int_32 nentries; /* number of palette entries */
+} png_sPLT_t;
+typedef png_sPLT_t FAR * png_sPLT_tp;
+typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
+
+#ifdef PNG_TEXT_SUPPORTED
+/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
+ * and whether that contents is compressed or not. The "key" field
+ * points to a regular zero-terminated C string. The "text", "lang", and
+ * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
+ * However, the * structure returned by png_get_text() will always contain
+ * regular zero-terminated C strings (possibly empty), never NULL pointers,
+ * so they can be safely used in printf() and other string-handling functions.
+ */
+typedef struct png_text_struct
+{
+ int compression; /* compression value:
+ -1: tEXt, none
+ 0: zTXt, deflate
+ 1: iTXt, none
+ 2: iTXt, deflate */
+ png_charp key; /* keyword, 1-79 character description of "text" */
+ png_charp text; /* comment, may be an empty string (ie "")
+ or a NULL pointer */
+ png_size_t text_length; /* length of the text string */
+#ifdef PNG_iTXt_SUPPORTED
+ png_size_t itxt_length; /* length of the itxt string */
+ png_charp lang; /* language code, 0-79 characters
+ or a NULL pointer */
+ png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
+ chars or a NULL pointer */
+#endif
+} png_text;
+typedef png_text FAR * png_textp;
+typedef png_text FAR * FAR * png_textpp;
+#endif
+
+/* Supported compression types for text in PNG files (tEXt, and zTXt).
+ * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
+#define PNG_TEXT_COMPRESSION_NONE_WR -3
+#define PNG_TEXT_COMPRESSION_zTXt_WR -2
+#define PNG_TEXT_COMPRESSION_NONE -1
+#define PNG_TEXT_COMPRESSION_zTXt 0
+#define PNG_ITXT_COMPRESSION_NONE 1
+#define PNG_ITXT_COMPRESSION_zTXt 2
+#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
+
+/* png_time is a way to hold the time in an machine independent way.
+ * Two conversions are provided, both from time_t and struct tm. There
+ * is no portable way to convert to either of these structures, as far
+ * as I know. If you know of a portable way, send it to me. As a side
+ * note - PNG has always been Year 2000 compliant!
+ */
+typedef struct png_time_struct
+{
+ png_uint_16 year; /* full year, as in, 1995 */
+ png_byte month; /* month of year, 1 - 12 */
+ png_byte day; /* day of month, 1 - 31 */
+ png_byte hour; /* hour of day, 0 - 23 */
+ png_byte minute; /* minute of hour, 0 - 59 */
+ png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
+} png_time;
+typedef png_time FAR * png_timep;
+typedef png_time FAR * FAR * png_timepp;
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+/* png_unknown_chunk is a structure to hold queued chunks for which there is
+ * no specific support. The idea is that we can use this to queue
+ * up private chunks for output even though the library doesn't actually
+ * know about their semantics.
+ */
+typedef struct png_unknown_chunk_t
+{
+ png_byte name[5];
+ png_byte *data;
+ png_size_t size;
+
+ /* libpng-using applications should NOT directly modify this byte. */
+ png_byte location; /* mode of operation at read time */
+}
+png_unknown_chunk;
+typedef png_unknown_chunk FAR * png_unknown_chunkp;
+typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
+#endif
+
+/* png_info is a structure that holds the information in a PNG file so
+ * that the application can find out the characteristics of the image.
+ * If you are reading the file, this structure will tell you what is
+ * in the PNG file. If you are writing the file, fill in the information
+ * you want to put into the PNG file, then call png_write_info().
+ * The names chosen should be very close to the PNG specification, so
+ * consult that document for information about the meaning of each field.
+ *
+ * With libpng < 0.95, it was only possible to directly set and read the
+ * the values in the png_info_struct, which meant that the contents and
+ * order of the values had to remain fixed. With libpng 0.95 and later,
+ * however, there are now functions that abstract the contents of
+ * png_info_struct from the application, so this makes it easier to use
+ * libpng with dynamic libraries, and even makes it possible to use
+ * libraries that don't have all of the libpng ancillary chunk-handing
+ * functionality.
+ *
+ * In any case, the order of the parameters in png_info_struct should NOT
+ * be changed for as long as possible to keep compatibility with applications
+ * that use the old direct-access method with png_info_struct.
+ *
+ * The following members may have allocated storage attached that should be
+ * cleaned up before the structure is discarded: palette, trans, text,
+ * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
+ * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
+ * are automatically freed when the info structure is deallocated, if they were
+ * allocated internally by libpng. This behavior can be changed by means
+ * of the png_data_freer() function.
+ *
+ * More allocation details: all the chunk-reading functions that
+ * change these members go through the corresponding png_set_*
+ * functions. A function to clear these members is available: see
+ * png_free_data(). The png_set_* functions do not depend on being
+ * able to point info structure members to any of the storage they are
+ * passed (they make their own copies), EXCEPT that the png_set_text
+ * functions use the same storage passed to them in the text_ptr or
+ * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
+ * functions do not make their own copies.
+ */
+typedef struct png_info_struct
+{
+ /* the following are necessary for every PNG file */
+ png_uint_32 width; /* width of image in pixels (from IHDR) */
+ png_uint_32 height; /* height of image in pixels (from IHDR) */
+ png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
+ png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
+ png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
+ png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
+ png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
+ png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
+ png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
+ /* The following three should have been named *_method not *_type */
+ png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
+ png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
+ png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
+
+ /* The following is informational only on read, and not used on writes. */
+ png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
+ png_byte pixel_depth; /* number of bits per pixel */
+ png_byte spare_byte; /* to align the data, and for future use */
+ png_byte signature[8]; /* magic bytes read by libpng from start of file */
+
+ /* The rest of the data is optional. If you are reading, check the
+ * valid field to see if the information in these are valid. If you
+ * are writing, set the valid field to those chunks you want written,
+ * and initialize the appropriate fields below.
+ */
+
+#if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+ /* The gAMA chunk describes the gamma characteristics of the system
+ * on which the image was created, normally in the range [1.0, 2.5].
+ * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
+ */
+ float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+ /* GR-P, 0.96a */
+ /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
+ png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+ /* The tEXt, and zTXt chunks contain human-readable textual data in
+ * uncompressed, compressed, and optionally compressed forms, respectively.
+ * The data in "text" is an array of pointers to uncompressed,
+ * null-terminated C strings. Each chunk has a keyword that describes the
+ * textual data contained in that chunk. Keywords are not required to be
+ * unique, and the text string may be empty. Any number of text chunks may
+ * be in an image.
+ */
+ int num_text; /* number of comments read/to write */
+ int max_text; /* current size of text array */
+ png_textp text; /* array of comments read/to write */
+#endif /* PNG_TEXT_SUPPORTED */
+
+#if defined(PNG_tIME_SUPPORTED)
+ /* The tIME chunk holds the last time the displayed image data was
+ * modified. See the png_time struct for the contents of this struct.
+ */
+ png_time mod_time;
+#endif
+
+#if defined(PNG_sBIT_SUPPORTED)
+ /* The sBIT chunk specifies the number of significant high-order bits
+ * in the pixel data. Values are in the range [1, bit_depth], and are
+ * only specified for the channels in the pixel data. The contents of
+ * the low-order bits is not specified. Data is valid if
+ * (valid & PNG_INFO_sBIT) is non-zero.
+ */
+ png_color_8 sig_bit; /* significant bits in color channels */
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
+defined(PNG_READ_BACKGROUND_SUPPORTED)
+ /* The tRNS chunk supplies transparency data for paletted images and
+ * other image types that don't need a full alpha channel. There are
+ * "num_trans" transparency values for a paletted image, stored in the
+ * same order as the palette colors, starting from index 0. Values
+ * for the data are in the range [0, 255], ranging from fully transparent
+ * to fully opaque, respectively. For non-paletted images, there is a
+ * single color specified that should be treated as fully transparent.
+ * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
+ */
+ png_bytep trans; /* transparent values for paletted image */
+ png_color_16 trans_values; /* transparent color for non-palette image */
+#endif
+
+#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ /* The bKGD chunk gives the suggested image background color if the
+ * display program does not have its own background color and the image
+ * is needs to composited onto a background before display. The colors
+ * in "background" are normally in the same color space/depth as the
+ * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
+ */
+ png_color_16 background;
+#endif
+
+#if defined(PNG_oFFs_SUPPORTED)
+ /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
+ * and downwards from the top-left corner of the display, page, or other
+ * application-specific co-ordinate space. See the PNG_OFFSET_ defines
+ * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
+ */
+ png_int_32 x_offset; /* x offset on page */
+ png_int_32 y_offset; /* y offset on page */
+ png_byte offset_unit_type; /* offset units type */
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+ /* The pHYs chunk gives the physical pixel density of the image for
+ * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
+ * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
+ */
+ png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
+ png_uint_32 y_pixels_per_unit; /* vertical pixel density */
+ png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+ /* The hIST chunk contains the relative frequency or importance of the
+ * various palette entries, so that a viewer can intelligently select a
+ * reduced-color palette, if required. Data is an array of "num_palette"
+ * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
+ * is non-zero.
+ */
+ png_uint_16p hist;
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+ /* The cHRM chunk describes the CIE color characteristics of the monitor
+ * on which the PNG was created. This data allows the viewer to do gamut
+ * mapping of the input image to ensure that the viewer sees the same
+ * colors in the image as the creator. Values are in the range
+ * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
+ */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float x_white;
+ float y_white;
+ float x_red;
+ float y_red;
+ float x_green;
+ float y_green;
+ float x_blue;
+ float y_blue;
+#endif
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+ /* The pCAL chunk describes a transformation between the stored pixel
+ * values and original physical data values used to create the image.
+ * The integer range [0, 2^bit_depth - 1] maps to the floating-point
+ * range given by [pcal_X0, pcal_X1], and are further transformed by a
+ * (possibly non-linear) transformation function given by "pcal_type"
+ * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
+ * defines below, and the PNG-Group's PNG extensions document for a
+ * complete description of the transformations and how they should be
+ * implemented, and for a description of the ASCII parameter strings.
+ * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
+ */
+ png_charp pcal_purpose; /* pCAL chunk description string */
+ png_int_32 pcal_X0; /* minimum value */
+ png_int_32 pcal_X1; /* maximum value */
+ png_charp pcal_units; /* Latin-1 string giving physical units */
+ png_charpp pcal_params; /* ASCII strings containing parameter values */
+ png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
+ png_byte pcal_nparams; /* number of parameters given in pcal_params */
+#endif
+
+/* New members added in libpng-1.0.6 */
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_uint_32 free_me; /* flags items libpng is responsible for freeing */
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+ /* storage for unknown chunks that the library doesn't recognize. */
+ png_unknown_chunkp unknown_chunks;
+ png_size_t unknown_chunks_num;
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+ /* iCCP chunk data. */
+ png_charp iccp_name; /* profile name */
+ png_charp iccp_profile; /* International Color Consortium profile data */
+ /* Note to maintainer: should be png_bytep */
+ png_uint_32 iccp_proflen; /* ICC profile data length */
+ png_byte iccp_compression; /* Always zero */
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+ /* data on sPLT chunks (there may be more than one). */
+ png_sPLT_tp splt_palettes;
+ png_uint_32 splt_palettes_num;
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+ /* The sCAL chunk describes the actual physical dimensions of the
+ * subject matter of the graphic. The chunk contains a unit specification
+ * a byte value, and two ASCII strings representing floating-point
+ * values. The values are width and height corresponsing to one pixel
+ * in the image. This external representation is converted to double
+ * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
+ */
+ png_byte scal_unit; /* unit of physical scale */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ double scal_pixel_width; /* width of one pixel */
+ double scal_pixel_height; /* height of one pixel */
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_charp scal_s_width; /* string containing height */
+ png_charp scal_s_height; /* string containing width */
+#endif
+#endif
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+ /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
+ /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
+ png_bytepp row_pointers; /* the image bits */
+#endif
+
+#if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
+ png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
+ png_fixed_point int_x_white;
+ png_fixed_point int_y_white;
+ png_fixed_point int_x_red;
+ png_fixed_point int_y_red;
+ png_fixed_point int_x_green;
+ png_fixed_point int_y_green;
+ png_fixed_point int_x_blue;
+ png_fixed_point int_y_blue;
+#endif
+
+} png_info;
+
+typedef png_info FAR * png_infop;
+typedef png_info FAR * FAR * png_infopp;
+
+/* Maximum positive integer used in PNG is (2^31)-1 */
+#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
+#define PNG_UINT_32_MAX ((png_uint_32)(-1))
+#define PNG_SIZE_MAX ((png_size_t)(-1))
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+/* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
+#define PNG_MAX_UINT PNG_UINT_31_MAX
+#endif
+
+/* These describe the color_type field in png_info. */
+/* color type masks */
+#define PNG_COLOR_MASK_PALETTE 1
+#define PNG_COLOR_MASK_COLOR 2
+#define PNG_COLOR_MASK_ALPHA 4
+
+/* color types. Note that not all combinations are legal */
+#define PNG_COLOR_TYPE_GRAY 0
+#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
+#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
+#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
+#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
+/* aliases */
+#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
+#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
+
+/* This is for compression type. PNG 1.0-1.2 only define the single type. */
+#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
+#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
+
+/* This is for filter type. PNG 1.0-1.2 only define the single type. */
+#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
+#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
+#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
+
+/* These are for the interlacing type. These values should NOT be changed. */
+#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
+#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
+#define PNG_INTERLACE_LAST 2 /* Not a valid value */
+
+/* These are for the oFFs chunk. These values should NOT be changed. */
+#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
+#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
+#define PNG_OFFSET_LAST 2 /* Not a valid value */
+
+/* These are for the pCAL chunk. These values should NOT be changed. */
+#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
+#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
+#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
+#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
+#define PNG_EQUATION_LAST 4 /* Not a valid value */
+
+/* These are for the sCAL chunk. These values should NOT be changed. */
+#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
+#define PNG_SCALE_METER 1 /* meters per pixel */
+#define PNG_SCALE_RADIAN 2 /* radians per pixel */
+#define PNG_SCALE_LAST 3 /* Not a valid value */
+
+/* These are for the pHYs chunk. These values should NOT be changed. */
+#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
+#define PNG_RESOLUTION_METER 1 /* pixels/meter */
+#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
+
+/* These are for the sRGB chunk. These values should NOT be changed. */
+#define PNG_sRGB_INTENT_PERCEPTUAL 0
+#define PNG_sRGB_INTENT_RELATIVE 1
+#define PNG_sRGB_INTENT_SATURATION 2
+#define PNG_sRGB_INTENT_ABSOLUTE 3
+#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
+
+/* This is for text chunks */
+#define PNG_KEYWORD_MAX_LENGTH 79
+
+/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
+#define PNG_MAX_PALETTE_LENGTH 256
+
+/* These determine if an ancillary chunk's data has been successfully read
+ * from the PNG header, or if the application has filled in the corresponding
+ * data in the info_struct to be written into the output file. The values
+ * of the PNG_INFO_<chunk> defines should NOT be changed.
+ */
+#define PNG_INFO_gAMA 0x0001
+#define PNG_INFO_sBIT 0x0002
+#define PNG_INFO_cHRM 0x0004
+#define PNG_INFO_PLTE 0x0008
+#define PNG_INFO_tRNS 0x0010
+#define PNG_INFO_bKGD 0x0020
+#define PNG_INFO_hIST 0x0040
+#define PNG_INFO_pHYs 0x0080
+#define PNG_INFO_oFFs 0x0100
+#define PNG_INFO_tIME 0x0200
+#define PNG_INFO_pCAL 0x0400
+#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
+#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
+#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
+#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
+#define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
+
+/* This is used for the transformation routines, as some of them
+ * change these values for the row. It also should enable using
+ * the routines for other purposes.
+ */
+typedef struct png_row_info_struct
+{
+ png_uint_32 width; /* width of row */
+ png_uint_32 rowbytes; /* number of bytes in row */
+ png_byte color_type; /* color type of row */
+ png_byte bit_depth; /* bit depth of row */
+ png_byte channels; /* number of channels (1, 2, 3, or 4) */
+ png_byte pixel_depth; /* bits per pixel (depth * channels) */
+} png_row_info;
+
+typedef png_row_info FAR * png_row_infop;
+typedef png_row_info FAR * FAR * png_row_infopp;
+
+/* These are the function types for the I/O functions and for the functions
+ * that allow the user to override the default I/O functions with his or her
+ * own. The png_error_ptr type should match that of user-supplied warning
+ * and error functions, while the png_rw_ptr type should match that of the
+ * user read/write data functions.
+ */
+typedef struct png_struct_def png_struct;
+typedef png_struct FAR * png_structp;
+
+typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
+typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
+typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
+typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
+ int));
+typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
+ int));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
+typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
+typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
+ png_uint_32, int));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_LEGACY_SUPPORTED)
+typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
+ png_row_infop, png_bytep));
+#endif
+
+#if defined(PNG_USER_CHUNKS_SUPPORTED)
+typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
+#endif
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
+#endif
+
+/* Transform masks for the high-level interface */
+#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
+#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
+#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
+#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
+#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
+#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
+#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
+#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
+#define PNG_TRANSFORM_BGR 0x0080 /* read and write */
+#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
+#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
+#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
+#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */
+
+/* Flags for MNG supported features */
+#define PNG_FLAG_MNG_EMPTY_PLTE 0x01
+#define PNG_FLAG_MNG_FILTER_64 0x04
+#define PNG_ALL_MNG_FEATURES 0x05
+
+typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
+typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
+
+/* The structure that holds the information to read and write PNG files.
+ * The only people who need to care about what is inside of this are the
+ * people who will be modifying the library for their own special needs.
+ * It should NOT be accessed directly by an application, except to store
+ * the jmp_buf.
+ */
+
+struct png_struct_def
+{
+#ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf jmpbuf; /* used in png_error */
+#endif
+ png_error_ptr error_fn; /* function for printing errors and aborting */
+ png_error_ptr warning_fn; /* function for printing warnings */
+ png_voidp error_ptr; /* user supplied struct for error functions */
+ png_rw_ptr write_data_fn; /* function for writing output data */
+ png_rw_ptr read_data_fn; /* function for reading input data */
+ png_voidp io_ptr; /* ptr to application struct for I/O functions */
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+ png_user_transform_ptr read_user_transform_fn; /* user read transform */
+#endif
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+ png_user_transform_ptr write_user_transform_fn; /* user write transform */
+#endif
+
+/* These were added in libpng-1.0.2 */
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+ png_voidp user_transform_ptr; /* user supplied struct for user transform */
+ png_byte user_transform_depth; /* bit depth of user transformed pixels */
+ png_byte user_transform_channels; /* channels in user transformed pixels */
+#endif
+#endif
+
+ png_uint_32 mode; /* tells us where we are in the PNG file */
+ png_uint_32 flags; /* flags indicating various things to libpng */
+ png_uint_32 transformations; /* which transformations to perform */
+
+ z_stream zstream; /* pointer to decompression structure (below) */
+ png_bytep zbuf; /* buffer for zlib */
+ png_size_t zbuf_size; /* size of zbuf */
+ int zlib_level; /* holds zlib compression level */
+ int zlib_method; /* holds zlib compression method */
+ int zlib_window_bits; /* holds zlib compression window bits */
+ int zlib_mem_level; /* holds zlib compression memory level */
+ int zlib_strategy; /* holds zlib compression strategy */
+
+ png_uint_32 width; /* width of image in pixels */
+ png_uint_32 height; /* height of image in pixels */
+ png_uint_32 num_rows; /* number of rows in current pass */
+ png_uint_32 usr_width; /* width of row at start of write */
+ png_uint_32 rowbytes; /* size of row in bytes */
+ png_uint_32 irowbytes; /* size of current interlaced row in bytes */
+ png_uint_32 iwidth; /* width of current interlaced row in pixels */
+ png_uint_32 row_number; /* current row in interlace pass */
+ png_bytep prev_row; /* buffer to save previous (unfiltered) row */
+ png_bytep row_buf; /* buffer to save current (unfiltered) row */
+ png_bytep sub_row; /* buffer to save "sub" row when filtering */
+ png_bytep up_row; /* buffer to save "up" row when filtering */
+ png_bytep avg_row; /* buffer to save "avg" row when filtering */
+ png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
+ png_row_info row_info; /* used for transformation routines */
+
+ png_uint_32 idat_size; /* current IDAT size for read */
+ png_uint_32 crc; /* current chunk CRC value */
+ png_colorp palette; /* palette from the input file */
+ png_uint_16 num_palette; /* number of color entries in palette */
+ png_uint_16 num_trans; /* number of transparency values */
+ png_byte chunk_name[5]; /* null-terminated name of current chunk */
+ png_byte compression; /* file compression type (always 0) */
+ png_byte filter; /* file filter type (always 0) */
+ png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
+ png_byte pass; /* current interlace pass (0 - 6) */
+ png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
+ png_byte color_type; /* color type of file */
+ png_byte bit_depth; /* bit depth of file */
+ png_byte usr_bit_depth; /* bit depth of users row */
+ png_byte pixel_depth; /* number of bits per pixel */
+ png_byte channels; /* number of channels in file */
+ png_byte usr_channels; /* channels at start of write */
+ png_byte sig_bytes; /* magic bytes read/written from start of file */
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+#ifdef PNG_LEGACY_SUPPORTED
+ png_byte filler; /* filler byte for pixel expansion */
+#else
+ png_uint_16 filler; /* filler bytes for pixel expansion */
+#endif
+#endif
+
+#if defined(PNG_bKGD_SUPPORTED)
+ png_byte background_gamma_type;
+# ifdef PNG_FLOATING_POINT_SUPPORTED
+ float background_gamma;
+# endif
+ png_color_16 background; /* background color in screen gamma space */
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ png_color_16 background_1; /* background normalized to gamma 1.0 */
+#endif
+#endif /* PNG_bKGD_SUPPORTED */
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+ png_flush_ptr output_flush_fn;/* Function for flushing output */
+ png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
+ png_uint_32 flush_rows; /* number of rows written since last flush */
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float gamma; /* file gamma value */
+ float screen_gamma; /* screen gamma value (display_exponent) */
+#endif
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ png_bytep gamma_table; /* gamma table for 8-bit depth files */
+ png_bytep gamma_from_1; /* converts from 1.0 to screen */
+ png_bytep gamma_to_1; /* converts from file to 1.0 */
+ png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
+ png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
+ png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
+ png_color_8 sig_bit; /* significant bits in each available channel */
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+ png_color_8 shift; /* shift for significant bit tranformation */
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
+ || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ png_bytep trans; /* transparency values for paletted files */
+ png_color_16 trans_values; /* transparency values for non-paletted files */
+#endif
+
+ png_read_status_ptr read_row_fn; /* called after each row is decoded */
+ png_write_status_ptr write_row_fn; /* called after each row is encoded */
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+ png_progressive_info_ptr info_fn; /* called after header data fully read */
+ png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
+ png_progressive_end_ptr end_fn; /* called after image is complete */
+ png_bytep save_buffer_ptr; /* current location in save_buffer */
+ png_bytep save_buffer; /* buffer for previously read data */
+ png_bytep current_buffer_ptr; /* current location in current_buffer */
+ png_bytep current_buffer; /* buffer for recently used data */
+ png_uint_32 push_length; /* size of current input chunk */
+ png_uint_32 skip_length; /* bytes to skip in input data */
+ png_size_t save_buffer_size; /* amount of data now in save_buffer */
+ png_size_t save_buffer_max; /* total size of save_buffer */
+ png_size_t buffer_size; /* total amount of available input data */
+ png_size_t current_buffer_size; /* amount of data now in current_buffer */
+ int process_mode; /* what push library is currently doing */
+ int cur_palette; /* current push library palette index */
+
+# if defined(PNG_TEXT_SUPPORTED)
+ png_size_t current_text_size; /* current size of text input data */
+ png_size_t current_text_left; /* how much text left to read in input */
+ png_charp current_text; /* current text chunk buffer */
+ png_charp current_text_ptr; /* current location in current_text */
+# endif /* PNG_TEXT_SUPPORTED */
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
+/* for the Borland special 64K segment handler */
+ png_bytepp offset_table_ptr;
+ png_bytep offset_table;
+ png_uint_16 offset_table_number;
+ png_uint_16 offset_table_count;
+ png_uint_16 offset_table_count_free;
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+ png_bytep palette_lookup; /* lookup table for dithering */
+ png_bytep dither_index; /* index translation for palette files */
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
+ png_uint_16p hist; /* histogram */
+#endif
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ png_byte heuristic_method; /* heuristic for row filter selection */
+ png_byte num_prev_filters; /* number of weights for previous rows */
+ png_bytep prev_filters; /* filter type(s) of previous row(s) */
+ png_uint_16p filter_weights; /* weight(s) for previous line(s) */
+ png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
+ png_uint_16p filter_costs; /* relative filter calculation cost */
+ png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+ png_charp time_buffer; /* String to hold RFC 1123 time text */
+#endif
+
+/* New members added in libpng-1.0.6 */
+
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_uint_32 free_me; /* flags items libpng is responsible for freeing */
+#endif
+
+#if defined(PNG_USER_CHUNKS_SUPPORTED)
+ png_voidp user_chunk_ptr;
+ png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+ int num_chunk_list;
+ png_bytep chunk_list;
+#endif
+
+/* New members added in libpng-1.0.3 */
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ png_byte rgb_to_gray_status;
+ /* These were changed from png_byte in libpng-1.0.6 */
+ png_uint_16 rgb_to_gray_red_coeff;
+ png_uint_16 rgb_to_gray_green_coeff;
+ png_uint_16 rgb_to_gray_blue_coeff;
+#endif
+
+/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
+#if defined(PNG_MNG_FEATURES_SUPPORTED) || \
+ defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+ defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+/* changed from png_byte to png_uint_32 at version 1.2.0 */
+#ifdef PNG_1_0_X
+ png_byte mng_features_permitted;
+#else
+ png_uint_32 mng_features_permitted;
+#endif /* PNG_1_0_X */
+#endif
+
+/* New member added in libpng-1.0.7 */
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ png_fixed_point int_gamma;
+#endif
+
+/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ png_byte filter_type;
+#endif
+
+#if defined(PNG_1_0_X)
+/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
+ png_uint_32 row_buf_size;
+#endif
+
+/* New members added in libpng-1.2.0 */
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+# if !defined(PNG_1_0_X)
+# if defined(PNG_MMX_CODE_SUPPORTED)
+ png_byte mmx_bitdepth_threshold;
+ png_uint_32 mmx_rowbytes_threshold;
+# endif
+ png_uint_32 asm_flags;
+# endif
+#endif
+
+/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_voidp mem_ptr; /* user supplied struct for mem functions */
+ png_malloc_ptr malloc_fn; /* function for allocating memory */
+ png_free_ptr free_fn; /* function for freeing memory */
+#endif
+
+/* New member added in libpng-1.0.13 and 1.2.0 */
+ png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+/* The following three members were added at version 1.0.14 and 1.2.4 */
+ png_bytep dither_sort; /* working sort array */
+ png_bytep index_to_palette; /* where the original index currently is */
+ /* in the palette */
+ png_bytep palette_to_index; /* which original index points to this */
+ /* palette color */
+#endif
+
+/* New members added in libpng-1.0.16 and 1.2.6 */
+ png_byte compression_type;
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ png_uint_32 user_width_max;
+ png_uint_32 user_height_max;
+#endif
+
+/* New member added in libpng-1.0.25 and 1.2.17 */
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+ /* storage for unknown chunk that the library doesn't recognize. */
+ png_unknown_chunk unknown_chunk;
+#endif
+};
+
+
+/* This triggers a compiler error in png.c, if png.c and png.h
+ * do not agree upon the version number.
+ */
+typedef png_structp version_1_2_22;
+
+typedef png_struct FAR * FAR * png_structpp;
+
+/* Here are the function definitions most commonly used. This is not
+ * the place to find out how to use libpng. See libpng.txt for the
+ * full explanation, see example.c for the summary. This just provides
+ * a simple one line description of the use of each function.
+ */
+
+/* Returns the version number of the library */
+extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
+
+/* Tell lib we have already handled the first <num_bytes> magic bytes.
+ * Handling more than 8 bytes from the beginning of the file is an error.
+ */
+extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
+ int num_bytes));
+
+/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
+ * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
+ * signature, and non-zero otherwise. Having num_to_check == 0 or
+ * start > 7 will always fail (ie return non-zero).
+ */
+extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
+ png_size_t num_to_check));
+
+/* Simple signature checking function. This is the same as calling
+ * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
+ */
+extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
+
+/* Allocate and initialize png_ptr struct for reading, and any other memory. */
+extern PNG_EXPORT(png_structp,png_create_read_struct)
+ PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn));
+
+/* Allocate and initialize png_ptr struct for writing, and any other memory */
+extern PNG_EXPORT(png_structp,png_create_write_struct)
+ PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn));
+
+#ifdef PNG_WRITE_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
+ PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+extern PNG_EXPORT(void,png_set_compression_buffer_size)
+ PNGARG((png_structp png_ptr, png_uint_32 size));
+#endif
+
+/* Reset the compression stream */
+extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
+
+/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
+#ifdef PNG_USER_MEM_SUPPORTED
+extern PNG_EXPORT(png_structp,png_create_read_struct_2)
+ PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+ png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+extern PNG_EXPORT(png_structp,png_create_write_struct_2)
+ PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+ png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+#endif
+
+/* Write a PNG chunk - size, type, (optional) data, CRC. */
+extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
+ png_bytep chunk_name, png_bytep data, png_size_t length));
+
+/* Write the start of a PNG chunk - length and chunk name. */
+extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
+ png_bytep chunk_name, png_uint_32 length));
+
+/* Write the data of a PNG chunk started with png_write_chunk_start(). */
+extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
+ png_bytep data, png_size_t length));
+
+/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
+extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
+
+/* Allocate and initialize the info structure */
+extern PNG_EXPORT(png_infop,png_create_info_struct)
+ PNGARG((png_structp png_ptr));
+
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+/* Initialize the info structure (old interface - DEPRECATED) */
+extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
+#undef png_info_init
+#define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
+ png_sizeof(png_info));
+#endif
+
+extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
+ png_size_t png_info_struct_size));
+
+/* Writes all the PNG information before the image. */
+extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read the information before the actual image data. */
+extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
+ PNGARG((png_structp png_ptr, png_timep ptime));
+#endif
+
+#if !defined(_WIN32_WCE)
+/* "time.h" functions are not supported on WindowsCE */
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+/* convert from a struct tm to png_time */
+extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
+ struct tm FAR * ttime));
+
+/* convert from time_t to png_time. Uses gmtime() */
+extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
+ time_t ttime));
+#endif /* PNG_WRITE_tIME_SUPPORTED */
+#endif /* _WIN32_WCE */
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
+extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
+#if !defined(PNG_1_0_X)
+extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp
+ png_ptr));
+#endif
+extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+/* Deprecated */
+extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
+#endif
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* Use blue, green, red order for pixels. */
+extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+/* Expand the grayscale to 24-bit RGB if necessary. */
+extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+/* Reduce RGB to grayscale. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
+ int error_action, double red, double green ));
+#endif
+extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
+ int error_action, png_fixed_point red, png_fixed_point green ));
+extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
+ png_ptr));
+#endif
+
+extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
+ png_colorp palette));
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
+ defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
+ defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
+extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
+ png_uint_32 filler, int flags));
+/* The values of the PNG_FILLER_ defines should NOT be changed */
+#define PNG_FILLER_BEFORE 0
+#define PNG_FILLER_AFTER 1
+/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
+#if !defined(PNG_1_0_X)
+extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
+ png_uint_32 filler, int flags));
+#endif
+#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* Swap bytes in 16-bit depth files. */
+extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
+extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+/* Swap packing order of pixels in bytes. */
+extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+/* Converts files to legal bit depths. */
+extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
+ png_color_8p true_bits));
+#endif
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+ defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* Have the code handle the interlacing. Returns the number of passes. */
+extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+/* Invert monochrome files */
+extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+/* Handle alpha and tRNS by replacing with a background color. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
+ png_color_16p background_color, int background_gamma_code,
+ int need_expand, double background_gamma));
+#endif
+#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
+#define PNG_BACKGROUND_GAMMA_SCREEN 1
+#define PNG_BACKGROUND_GAMMA_FILE 2
+#define PNG_BACKGROUND_GAMMA_UNIQUE 3
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+/* strip the second byte of information from a 16-bit depth file. */
+extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+/* Turn on dithering, and reduce the palette to the number of colors available. */
+extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
+ png_colorp palette, int num_palette, int maximum_colors,
+ png_uint_16p histogram, int full_dither));
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+/* Handle gamma correction. Screen_gamma=(display_exponent) */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
+ double screen_gamma, double default_file_gamma));
+#endif
+#endif
+
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+ defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
+/* Deprecated and will be removed. Use png_permit_mng_features() instead. */
+extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
+ int empty_plte_permitted));
+#endif
+#endif
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+/* Set how many lines between output flushes - 0 for no flushing */
+extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
+/* Flush the current PNG output buffer */
+extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
+#endif
+
+/* optional update palette with requested transformations */
+extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
+
+/* optional call to update the users info structure */
+extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read one or more rows of image data. */
+extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
+ png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
+#endif
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read a row of data. */
+extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
+ png_bytep row,
+ png_bytep display_row));
+#endif
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read the whole image into memory at once. */
+extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
+ png_bytepp image));
+#endif
+
+/* write a row of image data */
+extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
+ png_bytep row));
+
+/* write a few rows of image data */
+extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
+ png_bytepp row, png_uint_32 num_rows));
+
+/* write the image data */
+extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
+ png_bytepp image));
+
+/* writes the end of the PNG file. */
+extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read the end of the PNG file. */
+extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#endif
+
+/* free any memory associated with the png_info_struct */
+extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
+ png_infopp info_ptr_ptr));
+
+/* free any memory associated with the png_struct and the png_info_structs */
+extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
+ png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
+
+/* free all memory used by the read (old method - NOT DLL EXPORTED) */
+extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_infop end_info_ptr));
+
+/* free any memory associated with the png_struct and the png_info_structs */
+extern PNG_EXPORT(void,png_destroy_write_struct)
+ PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
+
+/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
+extern void png_write_destroy PNGARG((png_structp png_ptr));
+
+/* set the libpng method of handling chunk CRC errors */
+extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
+ int crit_action, int ancil_action));
+
+/* Values for png_set_crc_action() to say how to handle CRC errors in
+ * ancillary and critical chunks, and whether to use the data contained
+ * therein. Note that it is impossible to "discard" data in a critical
+ * chunk. For versions prior to 0.90, the action was always error/quit,
+ * whereas in version 0.90 and later, the action for CRC errors in ancillary
+ * chunks is warn/discard. These values should NOT be changed.
+ *
+ * value action:critical action:ancillary
+ */
+#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
+#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
+#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
+#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
+#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
+#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
+
+/* These functions give the user control over the scan-line filtering in
+ * libpng and the compression methods used by zlib. These functions are
+ * mainly useful for testing, as the defaults should work with most users.
+ * Those users who are tight on memory or want faster performance at the
+ * expense of compression can modify them. See the compression library
+ * header file (zlib.h) for an explination of the compression functions.
+ */
+
+/* set the filtering method(s) used by libpng. Currently, the only valid
+ * value for "method" is 0.
+ */
+extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
+ int filters));
+
+/* Flags for png_set_filter() to say which filters to use. The flags
+ * are chosen so that they don't conflict with real filter types
+ * below, in case they are supplied instead of the #defined constants.
+ * These values should NOT be changed.
+ */
+#define PNG_NO_FILTERS 0x00
+#define PNG_FILTER_NONE 0x08
+#define PNG_FILTER_SUB 0x10
+#define PNG_FILTER_UP 0x20
+#define PNG_FILTER_AVG 0x40
+#define PNG_FILTER_PAETH 0x80
+#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
+ PNG_FILTER_AVG | PNG_FILTER_PAETH)
+
+/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
+ * These defines should NOT be changed.
+ */
+#define PNG_FILTER_VALUE_NONE 0
+#define PNG_FILTER_VALUE_SUB 1
+#define PNG_FILTER_VALUE_UP 2
+#define PNG_FILTER_VALUE_AVG 3
+#define PNG_FILTER_VALUE_PAETH 4
+#define PNG_FILTER_VALUE_LAST 5
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
+/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
+ * defines, either the default (minimum-sum-of-absolute-differences), or
+ * the experimental method (weighted-minimum-sum-of-absolute-differences).
+ *
+ * Weights are factors >= 1.0, indicating how important it is to keep the
+ * filter type consistent between rows. Larger numbers mean the current
+ * filter is that many times as likely to be the same as the "num_weights"
+ * previous filters. This is cumulative for each previous row with a weight.
+ * There needs to be "num_weights" values in "filter_weights", or it can be
+ * NULL if the weights aren't being specified. Weights have no influence on
+ * the selection of the first row filter. Well chosen weights can (in theory)
+ * improve the compression for a given image.
+ *
+ * Costs are factors >= 1.0 indicating the relative decoding costs of a
+ * filter type. Higher costs indicate more decoding expense, and are
+ * therefore less likely to be selected over a filter with lower computational
+ * costs. There needs to be a value in "filter_costs" for each valid filter
+ * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
+ * setting the costs. Costs try to improve the speed of decompression without
+ * unduly increasing the compressed image size.
+ *
+ * A negative weight or cost indicates the default value is to be used, and
+ * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
+ * The default values for both weights and costs are currently 1.0, but may
+ * change if good general weighting/cost heuristics can be found. If both
+ * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
+ * to the UNWEIGHTED method, but with added encoding time/computation.
+ */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
+ int heuristic_method, int num_weights, png_doublep filter_weights,
+ png_doublep filter_costs));
+#endif
+#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+
+/* Heuristic used for row filter selection. These defines should NOT be
+ * changed.
+ */
+#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
+#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
+#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
+#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
+
+/* Set the library compression level. Currently, valid values range from
+ * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
+ * (0 - no compression, 9 - "maximal" compression). Note that tests have
+ * shown that zlib compression levels 3-6 usually perform as well as level 9
+ * for PNG images, and do considerably fewer caclulations. In the future,
+ * these values may not correspond directly to the zlib compression levels.
+ */
+extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
+ int level));
+
+extern PNG_EXPORT(void,png_set_compression_mem_level)
+ PNGARG((png_structp png_ptr, int mem_level));
+
+extern PNG_EXPORT(void,png_set_compression_strategy)
+ PNGARG((png_structp png_ptr, int strategy));
+
+extern PNG_EXPORT(void,png_set_compression_window_bits)
+ PNGARG((png_structp png_ptr, int window_bits));
+
+extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
+ int method));
+
+/* These next functions are called for input/output, memory, and error
+ * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
+ * and call standard C I/O routines such as fread(), fwrite(), and
+ * fprintf(). These functions can be made to use other I/O routines
+ * at run time for those applications that need to handle I/O in a
+ * different manner by calling png_set_???_fn(). See libpng.txt for
+ * more information.
+ */
+
+#if !defined(PNG_NO_STDIO)
+/* Initialize the input/output for the PNG file to the default functions. */
+extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
+#endif
+
+/* Replace the (error and abort), and warning functions with user
+ * supplied functions. If no messages are to be printed you must still
+ * write and use replacement functions. The replacement error_fn should
+ * still do a longjmp to the last setjmp location if you are using this
+ * method of error handling. If error_fn or warning_fn is NULL, the
+ * default function will be used.
+ */
+
+extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
+ png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
+
+/* Return the user pointer associated with the error functions */
+extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
+
+/* Replace the default data output functions with a user supplied one(s).
+ * If buffered output is not used, then output_flush_fn can be set to NULL.
+ * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
+ * output_flush_fn will be ignored (and thus can be NULL).
+ */
+extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
+ png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
+
+/* Replace the default data input function with a user supplied one. */
+extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
+ png_voidp io_ptr, png_rw_ptr read_data_fn));
+
+/* Return the user pointer associated with the I/O functions */
+extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
+
+extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
+ png_read_status_ptr read_row_fn));
+
+extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
+ png_write_status_ptr write_row_fn));
+
+#ifdef PNG_USER_MEM_SUPPORTED
+/* Replace the default memory allocation functions with user supplied one(s). */
+extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
+ png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+/* Return the user pointer associated with the memory functions */
+extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_LEGACY_SUPPORTED)
+extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
+ png_ptr, png_user_transform_ptr read_user_transform_fn));
+#endif
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_LEGACY_SUPPORTED)
+extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
+ png_ptr, png_user_transform_ptr write_user_transform_fn));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_LEGACY_SUPPORTED)
+extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
+ png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
+ int user_transform_channels));
+/* Return the user pointer associated with the user transform functions */
+extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
+ PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
+ png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
+extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
+ png_ptr));
+#endif
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+/* Sets the function callbacks for the push reader, and a pointer to a
+ * user-defined structure available to the callback functions.
+ */
+extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
+ png_voidp progressive_ptr,
+ png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
+ png_progressive_end_ptr end_fn));
+
+/* returns the user pointer associated with the push read functions */
+extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
+ PNGARG((png_structp png_ptr));
+
+/* function to be called when data becomes available */
+extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
+
+/* function that combines rows. Not very much different than the
+ * png_combine_row() call. Is this even used?????
+ */
+extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
+ png_bytep old_row, png_bytep new_row));
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
+ png_uint_32 size));
+
+#if defined(PNG_1_0_X)
+# define png_malloc_warn png_malloc
+#else
+/* Added at libpng version 1.2.4 */
+extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
+ png_uint_32 size));
+#endif
+
+/* frees a pointer allocated by png_malloc() */
+extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
+
+#if defined(PNG_1_0_X)
+/* Function to allocate memory for zlib. */
+extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
+ uInt size));
+
+/* Function to free memory for zlib */
+extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
+#endif
+
+/* Free data that was allocated internally */
+extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 free_me, int num));
+#ifdef PNG_FREE_ME_SUPPORTED
+/* Reassign responsibility for freeing existing data, whether allocated
+ * by libpng or by the application */
+extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int freer, png_uint_32 mask));
+#endif
+/* assignments for png_data_freer */
+#define PNG_DESTROY_WILL_FREE_DATA 1
+#define PNG_SET_WILL_FREE_DATA 1
+#define PNG_USER_WILL_FREE_DATA 2
+/* Flags for png_ptr->free_me and info_ptr->free_me */
+#define PNG_FREE_HIST 0x0008
+#define PNG_FREE_ICCP 0x0010
+#define PNG_FREE_SPLT 0x0020
+#define PNG_FREE_ROWS 0x0040
+#define PNG_FREE_PCAL 0x0080
+#define PNG_FREE_SCAL 0x0100
+#define PNG_FREE_UNKN 0x0200
+#define PNG_FREE_LIST 0x0400
+#define PNG_FREE_PLTE 0x1000
+#define PNG_FREE_TRNS 0x2000
+#define PNG_FREE_TEXT 0x4000
+#define PNG_FREE_ALL 0x7fff
+#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
+
+#ifdef PNG_USER_MEM_SUPPORTED
+extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
+ png_uint_32 size));
+extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
+ png_voidp ptr));
+#endif
+
+extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
+ png_voidp s1, png_voidp s2, png_uint_32 size));
+
+extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
+ png_voidp s1, int value, png_uint_32 size));
+
+#if defined(USE_FAR_KEYWORD) /* memory model conversion function */
+extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
+ int check));
+#endif /* USE_FAR_KEYWORD */
+
+#ifndef PNG_NO_ERROR_TEXT
+/* Fatal error in PNG image of libpng - can't continue */
+extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
+ png_const_charp error_message));
+
+/* The same, but the chunk name is prepended to the error string. */
+extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
+ png_const_charp error_message));
+#else
+/* Fatal error in PNG image of libpng - can't continue */
+extern PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr));
+#endif
+
+#ifndef PNG_NO_WARNINGS
+/* Non-fatal error in libpng. Can continue, but may have a problem. */
+extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
+ png_const_charp warning_message));
+
+#ifdef PNG_READ_SUPPORTED
+/* Non-fatal error in libpng, chunk name is prepended to message. */
+extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
+ png_const_charp warning_message));
+#endif /* PNG_READ_SUPPORTED */
+#endif /* PNG_NO_WARNINGS */
+
+/* The png_set_<chunk> functions are for storing values in the png_info_struct.
+ * Similarly, the png_get_<chunk> calls are used to read values from the
+ * png_info_struct, either storing the parameters in the passed variables, or
+ * setting pointers into the png_info_struct where the data is stored. The
+ * png_get_<chunk> functions return a non-zero value if the data was available
+ * in info_ptr, or return zero and do not change any of the parameters if the
+ * data was not available.
+ *
+ * These functions should be used instead of directly accessing png_info
+ * to avoid problems with future changes in the size and internal layout of
+ * png_info_struct.
+ */
+/* Returns "flag" if chunk data is valid in info_ptr. */
+extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
+png_infop info_ptr, png_uint_32 flag));
+
+/* Returns number of bytes needed to hold a transformed row. */
+extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+/* Returns row_pointers, which is an array of pointers to scanlines that was
+returned from png_read_png(). */
+extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+/* Set row_pointers, which is an array of pointers to scanlines for use
+by png_write_png(). */
+extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_bytepp row_pointers));
+#endif
+
+/* Returns number of color channels in image. */
+extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* Returns image width in pixels. */
+extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image height in pixels. */
+extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image bit_depth. */
+extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image color_type. */
+extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image filter_type. */
+extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image interlace_type. */
+extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image compression_type. */
+extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image resolution in pixels per meter, from pHYs chunk data. */
+extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns pixel aspect ratio, computed from pHYs chunk data. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+#endif
+
+/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
+extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+#endif /* PNG_EASY_ACCESS_SUPPORTED */
+
+/* Returns pointer to signature string read from PNG header */
+extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#if defined(PNG_bKGD_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_color_16p *background));
+#endif
+
+#if defined(PNG_bKGD_SUPPORTED)
+extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_color_16p background));
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, double *white_x, double *white_y, double *red_x,
+ double *red_y, double *green_x, double *green_y, double *blue_x,
+ double *blue_y));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
+ *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
+ png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
+ *int_blue_x, png_fixed_point *int_blue_y));
+#endif
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, double white_x, double white_y, double red_x,
+ double red_y, double green_x, double green_y, double blue_x, double blue_y));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
+ png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
+ int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
+ png_fixed_point int_blue_y));
+#endif
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, double *file_gamma));
+#endif
+extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_fixed_point *int_file_gamma));
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, double file_gamma));
+#endif
+extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_fixed_point int_file_gamma));
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_16p *hist));
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_16p hist));
+#endif
+
+extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
+ int *bit_depth, int *color_type, int *interlace_method,
+ int *compression_method, int *filter_method));
+
+extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
+ int color_type, int interlace_method, int compression_method,
+ int filter_method));
+
+#if defined(PNG_oFFs_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
+ int *unit_type));
+#endif
+
+#if defined(PNG_oFFs_SUPPORTED)
+extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
+ int unit_type));
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
+ int *type, int *nparams, png_charp *units, png_charpp *params));
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
+ int type, int nparams, png_charp units, png_charpp params));
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
+#endif
+
+extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_colorp *palette, int *num_palette));
+
+extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_colorp palette, int num_palette));
+
+#if defined(PNG_sBIT_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_color_8p *sig_bit));
+#endif
+
+#if defined(PNG_sBIT_SUPPORTED)
+extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_color_8p sig_bit));
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int *intent));
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int intent));
+extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int intent));
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_charpp name, int *compression_type,
+ png_charpp profile, png_uint_32 *proflen));
+ /* Note to maintainer: profile should be png_bytepp */
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_charp name, int compression_type,
+ png_charp profile, png_uint_32 proflen));
+ /* Note to maintainer: profile should be png_bytep */
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_sPLT_tpp entries));
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_sPLT_tp entries, int nentries));
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+/* png_get_text also returns the number of text chunks in *num_text */
+extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_textp *text_ptr, int *num_text));
+#endif
+
+/*
+ * Note while png_set_text() will accept a structure whose text,
+ * language, and translated keywords are NULL pointers, the structure
+ * returned by png_get_text will always contain regular
+ * zero-terminated C strings. They might be empty strings but
+ * they will never be NULL pointers.
+ */
+
+#if defined(PNG_TEXT_SUPPORTED)
+extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_textp text_ptr, int num_text));
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_timep *mod_time));
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_timep mod_time));
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_bytep *trans, int *num_trans,
+ png_color_16p *trans_values));
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_bytep trans, int num_trans,
+ png_color_16p trans_values));
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int *unit, double *width, double *height));
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
+#endif
+#endif
+#endif /* PNG_sCAL_SUPPORTED */
+
+#if defined(PNG_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int unit, double width, double height));
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
+#endif
+#endif
+#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+/* provide a list of chunks and how they are to be handled, if the built-in
+ handling or default unknown chunk handling is not desired. Any chunks not
+ listed will be handled in the default manner. The IHDR and IEND chunks
+ must not be listed.
+ keep = 0: follow default behaviour
+ = 1: do not keep
+ = 2: keep only if safe-to-copy
+ = 3: keep even if unsafe-to-copy
+*/
+extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
+ png_ptr, int keep, png_bytep chunk_list, int num_chunks));
+extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
+extern PNG_EXPORT(void, png_set_unknown_chunk_location)
+ PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
+extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
+ png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
+#endif
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
+ chunk_name));
+#endif
+
+/* Png_free_data() will turn off the "valid" flag for anything it frees.
+ If you need to turn it off for a chunk that your application has freed,
+ you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
+extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int mask));
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+/* The "params" pointer is currently not used and is for future expansion. */
+extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
+ png_infop info_ptr,
+ int transforms,
+ png_voidp params));
+extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
+ png_infop info_ptr,
+ int transforms,
+ png_voidp params));
+#endif
+
+/* Define PNG_DEBUG at compile time for debugging information. Higher
+ * numbers for PNG_DEBUG mean more debugging information. This has
+ * only been added since version 0.95 so it is not implemented throughout
+ * libpng yet, but more support will be added as needed.
+ */
+#ifdef PNG_DEBUG
+#if (PNG_DEBUG > 0)
+#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
+#include <crtdbg.h>
+#if (PNG_DEBUG > 1)
+#define png_debug(l,m) _RPT0(_CRT_WARN,m)
+#define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1)
+#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
+#endif
+#else /* PNG_DEBUG_FILE || !_MSC_VER */
+#ifndef PNG_DEBUG_FILE
+#define PNG_DEBUG_FILE stderr
+#endif /* PNG_DEBUG_FILE */
+#if (PNG_DEBUG > 1)
+#define png_debug(l,m) \
+{ \
+ int num_tabs=l; \
+ fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
+ (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
+}
+#define png_debug1(l,m,p1) \
+{ \
+ int num_tabs=l; \
+ fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
+ (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
+}
+#define png_debug2(l,m,p1,p2) \
+{ \
+ int num_tabs=l; \
+ fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
+ (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
+}
+#endif /* (PNG_DEBUG > 1) */
+#endif /* _MSC_VER */
+#endif /* (PNG_DEBUG > 0) */
+#endif /* PNG_DEBUG */
+#ifndef png_debug
+#define png_debug(l, m)
+#endif
+#ifndef png_debug1
+#define png_debug1(l, m, p1)
+#endif
+#ifndef png_debug2
+#define png_debug2(l, m, p1, p2)
+#endif
+
+extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
+ png_ptr, png_uint_32 mng_features_permitted));
+#endif
+
+/* For use in png_set_keep_unknown, added to version 1.2.6 */
+#define PNG_HANDLE_CHUNK_AS_DEFAULT 0
+#define PNG_HANDLE_CHUNK_NEVER 1
+#define PNG_HANDLE_CHUNK_IF_SAFE 2
+#define PNG_HANDLE_CHUNK_ALWAYS 3
+
+/* Added to version 1.2.0 */
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+#if defined(PNG_MMX_CODE_SUPPORTED)
+#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
+#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
+#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
+#define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
+#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
+#define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
+#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
+#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
+#define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
+
+#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
+ | PNG_ASM_FLAG_MMX_READ_INTERLACE \
+ | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
+ | PNG_ASM_FLAG_MMX_READ_FILTER_UP \
+ | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
+ | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
+#define PNG_MMX_WRITE_FLAGS ( 0 )
+
+#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
+ | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
+ | PNG_MMX_READ_FLAGS \
+ | PNG_MMX_WRITE_FLAGS )
+
+#define PNG_SELECT_READ 1
+#define PNG_SELECT_WRITE 2
+#endif /* PNG_MMX_CODE_SUPPORTED */
+
+#if !defined(PNG_1_0_X)
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
+ PNGARG((int flag_select, int *compilerID));
+
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
+ PNGARG((int flag_select));
+
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
+ PNGARG((png_structp png_ptr));
+
+/* pngget.c */
+extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
+ PNGARG((png_structp png_ptr));
+
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
+ PNGARG((png_structp png_ptr));
+
+/* pngset.c */
+extern PNG_EXPORT(void,png_set_asm_flags)
+ PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
+
+/* pngset.c */
+extern PNG_EXPORT(void,png_set_mmx_thresholds)
+ PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
+ png_uint_32 mmx_rowbytes_threshold));
+
+#endif /* PNG_1_0_X */
+
+#if !defined(PNG_1_0_X)
+/* png.c, pnggccrd.c, or pngvcrd.c */
+extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+
+/* Strip the prepended error numbers ("#nnn ") from error and warning
+ * messages before passing them to the error or warning handler. */
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
+ png_ptr, png_uint_32 strip_mode));
+#endif
+
+#endif /* PNG_1_0_X */
+
+/* Added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
+ png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
+extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
+ png_ptr));
+extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
+ png_ptr));
+#endif
+
+/* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
+
+#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
+/* With these routines we avoid an integer divide, which will be slower on
+ * most machines. However, it does take more operations than the corresponding
+ * divide method, so it may be slower on a few RISC systems. There are two
+ * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
+ *
+ * Note that the rounding factors are NOT supposed to be the same! 128 and
+ * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
+ * standard method.
+ *
+ * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
+ */
+
+ /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
+
+# define png_composite(composite, fg, alpha, bg) \
+ { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
+ + (png_uint_16)(bg)*(png_uint_16)(255 - \
+ (png_uint_16)(alpha)) + (png_uint_16)128); \
+ (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
+
+# define png_composite_16(composite, fg, alpha, bg) \
+ { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
+ + (png_uint_32)(bg)*(png_uint_32)(65535L - \
+ (png_uint_32)(alpha)) + (png_uint_32)32768L); \
+ (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
+
+#else /* standard method using integer division */
+
+# define png_composite(composite, fg, alpha, bg) \
+ (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
+ (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
+ (png_uint_16)127) / 255)
+
+# define png_composite_16(composite, fg, alpha, bg) \
+ (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
+ (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
+ (png_uint_32)32767) / (png_uint_32)65535L)
+
+#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
+
+/* Inline macros to do direct reads of bytes from the input buffer. These
+ * require that you are using an architecture that uses PNG byte ordering
+ * (MSB first) and supports unaligned data storage. I think that PowerPC
+ * in big-endian mode and 680x0 are the only ones that will support this.
+ * The x86 line of processors definitely do not. The png_get_int_32()
+ * routine also assumes we are using two's complement format for negative
+ * values, which is almost certainly true.
+ */
+#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
+# define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
+# define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
+# define png_get_int_32(buf) ( *((png_int_32p) (buf)))
+#else
+extern PNG_EXPORT(png_uint_32,png_get_uint_32) PNGARG((png_bytep buf));
+extern PNG_EXPORT(png_uint_16,png_get_uint_16) PNGARG((png_bytep buf));
+extern PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf));
+#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
+extern PNG_EXPORT(png_uint_32,png_get_uint_31)
+ PNGARG((png_structp png_ptr, png_bytep buf));
+/* No png_get_int_16 -- may be added if there's a real need for it. */
+
+/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
+ */
+extern PNG_EXPORT(void,png_save_uint_32)
+ PNGARG((png_bytep buf, png_uint_32 i));
+extern PNG_EXPORT(void,png_save_int_32)
+ PNGARG((png_bytep buf, png_int_32 i));
+
+/* Place a 16-bit number into a buffer in PNG byte order.
+ * The parameter is declared unsigned int, not png_uint_16,
+ * just to avoid potential problems on pre-ANSI C compilers.
+ */
+extern PNG_EXPORT(void,png_save_uint_16)
+ PNGARG((png_bytep buf, unsigned int i));
+/* No png_save_int_16 -- may be added if there's a real need for it. */
+
+/* ************************************************************************* */
+
+/* These next functions are used internally in the code. They generally
+ * shouldn't be used unless you are writing code to add or replace some
+ * functionality in libpng. More information about most functions can
+ * be found in the files where the functions are located.
+ */
+
+
+/* Various modes of operation, that are visible to applications because
+ * they are used for unknown chunk location.
+ */
+#define PNG_HAVE_IHDR 0x01
+#define PNG_HAVE_PLTE 0x02
+#define PNG_HAVE_IDAT 0x04
+#define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */
+#define PNG_HAVE_IEND 0x10
+
+#if defined(PNG_INTERNAL)
+
+/* More modes of operation. Note that after an init, mode is set to
+ * zero automatically when the structure is created.
+ */
+#define PNG_HAVE_gAMA 0x20
+#define PNG_HAVE_cHRM 0x40
+#define PNG_HAVE_sRGB 0x80
+#define PNG_HAVE_CHUNK_HEADER 0x100
+#define PNG_WROTE_tIME 0x200
+#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
+#define PNG_BACKGROUND_IS_GRAY 0x800
+#define PNG_HAVE_PNG_SIGNATURE 0x1000
+#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
+
+/* flags for the transformations the PNG library does on the image data */
+#define PNG_BGR 0x0001
+#define PNG_INTERLACE 0x0002
+#define PNG_PACK 0x0004
+#define PNG_SHIFT 0x0008
+#define PNG_SWAP_BYTES 0x0010
+#define PNG_INVERT_MONO 0x0020
+#define PNG_DITHER 0x0040
+#define PNG_BACKGROUND 0x0080
+#define PNG_BACKGROUND_EXPAND 0x0100
+ /* 0x0200 unused */
+#define PNG_16_TO_8 0x0400
+#define PNG_RGBA 0x0800
+#define PNG_EXPAND 0x1000
+#define PNG_GAMMA 0x2000
+#define PNG_GRAY_TO_RGB 0x4000
+#define PNG_FILLER 0x8000L
+#define PNG_PACKSWAP 0x10000L
+#define PNG_SWAP_ALPHA 0x20000L
+#define PNG_STRIP_ALPHA 0x40000L
+#define PNG_INVERT_ALPHA 0x80000L
+#define PNG_USER_TRANSFORM 0x100000L
+#define PNG_RGB_TO_GRAY_ERR 0x200000L
+#define PNG_RGB_TO_GRAY_WARN 0x400000L
+#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
+ /* 0x800000L Unused */
+#define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
+#define PNG_EXPAND_tRNS 0x2000000L /* Added to libpng-1.2.9 */
+ /* 0x4000000L unused */
+ /* 0x8000000L unused */
+ /* 0x10000000L unused */
+ /* 0x20000000L unused */
+ /* 0x40000000L unused */
+
+/* flags for png_create_struct */
+#define PNG_STRUCT_PNG 0x0001
+#define PNG_STRUCT_INFO 0x0002
+
+/* Scaling factor for filter heuristic weighting calculations */
+#define PNG_WEIGHT_SHIFT 8
+#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
+#define PNG_COST_SHIFT 3
+#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
+
+/* flags for the png_ptr->flags rather than declaring a byte for each one */
+#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
+#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
+#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
+#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
+#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
+#define PNG_FLAG_ZLIB_FINISHED 0x0020
+#define PNG_FLAG_ROW_INIT 0x0040
+#define PNG_FLAG_FILLER_AFTER 0x0080
+#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
+#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
+#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
+#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
+#define PNG_FLAG_FREE_PLTE 0x1000
+#define PNG_FLAG_FREE_TRNS 0x2000
+#define PNG_FLAG_FREE_HIST 0x4000
+#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
+#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
+#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
+#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
+#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
+#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
+#define PNG_FLAG_ADD_ALPHA 0x200000L /* Added to libpng-1.2.8 */
+#define PNG_FLAG_STRIP_ALPHA 0x400000L /* Added to libpng-1.2.8 */
+ /* 0x800000L unused */
+ /* 0x1000000L unused */
+ /* 0x2000000L unused */
+ /* 0x4000000L unused */
+ /* 0x8000000L unused */
+ /* 0x10000000L unused */
+ /* 0x20000000L unused */
+ /* 0x40000000L unused */
+
+#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
+ PNG_FLAG_CRC_ANCILLARY_NOWARN)
+
+#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
+ PNG_FLAG_CRC_CRITICAL_IGNORE)
+
+#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
+ PNG_FLAG_CRC_CRITICAL_MASK)
+
+/* save typing and make code easier to understand */
+
+#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
+ abs((int)((c1).green) - (int)((c2).green)) + \
+ abs((int)((c1).blue) - (int)((c2).blue)))
+
+/* Added to libpng-1.2.6 JB */
+#define PNG_ROWBYTES(pixel_bits, width) \
+ ((pixel_bits) >= 8 ? \
+ ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
+ (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
+
+/* PNG_OUT_OF_RANGE returns true if value is outside the range
+ ideal-delta..ideal+delta. Each argument is evaluated twice.
+ "ideal" and "delta" should be constants, normally simple
+ integers, "value" a variable. Added to libpng-1.2.6 JB */
+#define PNG_OUT_OF_RANGE(value, ideal, delta) \
+ ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
+
+/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
+#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
+/* place to hold the signature string for a PNG file. */
+#ifdef PNG_USE_GLOBAL_ARRAYS
+ PNG_EXPORT_VAR (PNG_CONST png_byte FARDATA) png_sig[8];
+#else
+#endif
+#endif /* PNG_NO_EXTERN */
+
+/* Constant strings for known chunk types. If you need to add a chunk,
+ * define the name here, and add an invocation of the macro in png.c and
+ * wherever it's needed.
+ */
+#define PNG_IHDR png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
+#define PNG_IDAT png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
+#define PNG_IEND png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
+#define PNG_PLTE png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
+#define PNG_bKGD png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
+#define PNG_cHRM png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
+#define PNG_gAMA png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
+#define PNG_hIST png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
+#define PNG_iCCP png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
+#define PNG_iTXt png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
+#define PNG_oFFs png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
+#define PNG_pCAL png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
+#define PNG_sCAL png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
+#define PNG_pHYs png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
+#define PNG_sBIT png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
+#define PNG_sPLT png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
+#define PNG_sRGB png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
+#define PNG_tEXt png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
+#define PNG_tIME png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
+#define PNG_tRNS png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
+#define PNG_zTXt png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+PNG_EXPORT_VAR (png_byte FARDATA) png_IHDR[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_IDAT[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_IEND[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_PLTE[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_bKGD[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_cHRM[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_gAMA[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_hIST[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_iCCP[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_iTXt[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_oFFs[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_pCAL[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_sCAL[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_pHYs[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_sBIT[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_sPLT[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_sRGB[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_tEXt[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_tIME[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_tRNS[5];
+PNG_EXPORT_VAR (png_byte FARDATA) png_zTXt[5];
+#endif /* PNG_USE_GLOBAL_ARRAYS */
+
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+/* Initialize png_ptr struct for reading, and allocate any other memory.
+ * (old interface - DEPRECATED - use png_create_read_struct instead).
+ */
+extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
+#undef png_read_init
+#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
+ PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
+#endif
+
+extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
+ png_const_charp user_png_ver, png_size_t png_struct_size));
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
+ png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
+ png_info_size));
+#endif
+
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+/* Initialize png_ptr struct for writing, and allocate any other memory.
+ * (old interface - DEPRECATED - use png_create_write_struct instead).
+ */
+extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
+#undef png_write_init
+#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
+ PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
+#endif
+
+extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
+ png_const_charp user_png_ver, png_size_t png_struct_size));
+extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
+ png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
+ png_info_size));
+
+/* Allocate memory for an internal libpng struct */
+PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
+
+/* Free memory from internal libpng struct */
+PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
+
+PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
+ malloc_fn, png_voidp mem_ptr));
+PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
+ png_free_ptr free_fn, png_voidp mem_ptr));
+
+/* Free any memory that info_ptr points to and reset struct. */
+PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+#ifndef PNG_1_0_X
+/* Function to allocate memory for zlib. */
+PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
+
+/* Function to free memory for zlib */
+PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
+
+#ifdef PNG_SIZE_T
+/* Function to convert a sizeof an item to png_sizeof item */
+ PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
+#endif
+
+/* Next four functions are used internally as callbacks. PNGAPI is required
+ * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
+
+PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
+ png_bytep data, png_size_t length));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
+ png_bytep buffer, png_size_t length));
+#endif
+
+PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
+ png_bytep data, png_size_t length));
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+#if !defined(PNG_NO_STDIO)
+PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
+#endif
+#endif
+#else /* PNG_1_0_X */
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
+ png_bytep buffer, png_size_t length));
+#endif
+#endif /* PNG_1_0_X */
+
+/* Reset the CRC variable */
+PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
+
+/* Write the "data" buffer to whatever output you are using. */
+PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
+ png_size_t length));
+
+/* Read data from whatever input you are using into the "data" buffer */
+PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
+ png_size_t length));
+
+/* Read bytes into buf, and update png_ptr->crc */
+PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
+ png_size_t length));
+
+/* Decompress data in a chunk that uses compression */
+#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
+ defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
+PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
+ int comp_type, png_charp chunkdata, png_size_t chunklength,
+ png_size_t prefix_length, png_size_t *data_length));
+#endif
+
+/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
+PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
+
+/* Read the CRC from the file and compare it to the libpng calculated CRC */
+PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
+
+/* Calculate the CRC over a section of data. Note that we are only
+ * passing a maximum of 64K on systems that have this as a memory limit,
+ * since this is the maximum buffer size we can specify.
+ */
+PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
+ png_size_t length));
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
+#endif
+
+/* simple function to write the signature */
+PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
+
+/* write various chunks */
+
+/* Write the IHDR chunk, and update the png_struct with the necessary
+ * information.
+ */
+PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
+ png_uint_32 height,
+ int bit_depth, int color_type, int compression_method, int filter_method,
+ int interlace_method));
+
+PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
+ png_uint_32 num_pal));
+
+PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
+ png_size_t length));
+
+PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
+
+#if defined(PNG_WRITE_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
+ file_gamma));
+#endif
+#endif
+
+#if defined(PNG_WRITE_sBIT_SUPPORTED)
+PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
+ int color_type));
+#endif
+
+#if defined(PNG_WRITE_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
+ double white_x, double white_y,
+ double red_x, double red_y, double green_x, double green_y,
+ double blue_x, double blue_y));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
+ png_fixed_point int_white_x, png_fixed_point int_white_y,
+ png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
+ int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
+ png_fixed_point int_blue_y));
+#endif
+#endif
+
+#if defined(PNG_WRITE_sRGB_SUPPORTED)
+PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
+ int intent));
+#endif
+
+#if defined(PNG_WRITE_iCCP_SUPPORTED)
+PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
+ png_charp name, int compression_type,
+ png_charp profile, int proflen));
+ /* Note to maintainer: profile should be png_bytep */
+#endif
+
+#if defined(PNG_WRITE_sPLT_SUPPORTED)
+PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
+ png_sPLT_tp palette));
+#endif
+
+#if defined(PNG_WRITE_tRNS_SUPPORTED)
+PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
+ png_color_16p values, int number, int color_type));
+#endif
+
+#if defined(PNG_WRITE_bKGD_SUPPORTED)
+PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
+ png_color_16p values, int color_type));
+#endif
+
+#if defined(PNG_WRITE_hIST_SUPPORTED)
+PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
+ int num_hist));
+#endif
+
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
+ defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
+ png_charp key, png_charpp new_key));
+#endif
+
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
+ png_charp text, png_size_t text_len));
+#endif
+
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
+ png_charp text, png_size_t text_len, int compression));
+#endif
+
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
+ int compression, png_charp key, png_charp lang, png_charp lang_key,
+ png_charp text));
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
+PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_textp text_ptr, int num_text));
+#endif
+
+#if defined(PNG_WRITE_oFFs_SUPPORTED)
+PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
+ png_int_32 x_offset, png_int_32 y_offset, int unit_type));
+#endif
+
+#if defined(PNG_WRITE_pCAL_SUPPORTED)
+PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
+ png_int_32 X0, png_int_32 X1, int type, int nparams,
+ png_charp units, png_charpp params));
+#endif
+
+#if defined(PNG_WRITE_pHYs_SUPPORTED)
+PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
+ png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
+ int unit_type));
+#endif
+
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
+ png_timep mod_time));
+#endif
+
+#if defined(PNG_WRITE_sCAL_SUPPORTED)
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
+PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
+ int unit, double width, double height));
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
+ int unit, png_charp width, png_charp height));
+#endif
+#endif
+#endif
+
+/* Called when finished processing a row of data */
+PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
+
+/* Internal use only. Called before first row of data */
+PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
+#endif
+
+/* combine a row of data, dealing with alpha, etc. if requested */
+PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
+ int mask));
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+/* expand an interlaced row */
+/* OLD pre-1.0.9 interface:
+PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
+ png_bytep row, int pass, png_uint_32 transformations));
+ */
+PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
+#endif
+
+/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* grab pixels out of a row for an interlaced pass */
+PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
+ png_bytep row, int pass));
+#endif
+
+/* unfilter a row */
+PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
+ png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
+
+/* Choose the best filter to use and filter the row data */
+PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
+ png_row_infop row_info));
+
+/* Write out the filtered row. */
+PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
+ png_bytep filtered_row));
+/* finish a row while reading, dealing with interlacing passes, etc. */
+PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
+
+/* initialize the row buffers, etc. */
+PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
+/* optional call to update the users info structure */
+PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+/* these are the functions that do the transformations */
+#if defined(PNG_READ_FILLER_SUPPORTED)
+PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
+ png_bytep row, png_uint_32 filler, png_uint_32 flags));
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
+ defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
+ png_bytep row, png_uint_32 flags));
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
+ row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
+ png_color_8p sig_bits));
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
+ png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
+
+# if defined(PNG_CORRECT_PALETTE_SUPPORTED)
+PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
+ png_colorp palette, int num_palette));
+# endif
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
+ png_bytep row, png_uint_32 bit_depth));
+#endif
+
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
+ png_color_8p bit_depth));
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
+ png_color_16p trans_values, png_color_16p background,
+ png_color_16p background_1,
+ png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
+ png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
+ png_uint_16pp gamma_16_to_1, int gamma_shift));
+#else
+PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
+ png_color_16p trans_values, png_color_16p background));
+#endif
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
+ png_bytep gamma_table, png_uint_16pp gamma_16_table,
+ int gamma_shift));
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
+ png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
+PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
+ png_bytep row, png_color_16p trans_value));
+#endif
+
+/* The following decodes the appropriate chunks, and does error correction,
+ * then calls the appropriate callback for the chunk if it is valid.
+ */
+
+/* decode the IHDR chunk */
+PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+
+#if defined(PNG_READ_bKGD_SUPPORTED)
+PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_cHRM_SUPPORTED)
+PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_gAMA_SUPPORTED)
+PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_hIST_SUPPORTED)
+PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_iCCP_SUPPORTED)
+extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif /* PNG_READ_iCCP_SUPPORTED */
+
+#if defined(PNG_READ_iTXt_SUPPORTED)
+PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_oFFs_SUPPORTED)
+PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_pCAL_SUPPORTED)
+PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_pHYs_SUPPORTED)
+PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_sBIT_SUPPORTED)
+PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_sCAL_SUPPORTED)
+PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_sPLT_SUPPORTED)
+extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif /* PNG_READ_sPLT_SUPPORTED */
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_tEXt_SUPPORTED)
+PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_tIME_SUPPORTED)
+PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_tRNS_SUPPORTED)
+PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_zTXt_SUPPORTED)
+PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+
+PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
+ png_bytep chunk_name));
+
+/* handle the transformations for reading and writing */
+PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
+
+PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
+ png_uint_32 length));
+PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
+ png_bytep buffer, png_size_t buffer_length));
+PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
+ png_bytep buffer, png_size_t buffer_length));
+PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
+PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
+#if defined(PNG_READ_tEXt_SUPPORTED)
+PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#endif
+
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
+ png_bytep row));
+PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+#if defined(PNG_MMX_CODE_SUPPORTED)
+/* png.c */ /* PRIVATE */
+PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
+#endif
+#endif
+
+#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
+PNG_EXTERN png_uint_32 png_get_pixels_per_inch PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXTERN png_uint_32 png_get_x_pixels_per_inch PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXTERN png_uint_32 png_get_y_pixels_per_inch PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXTERN float png_get_x_offset_inches PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXTERN float png_get_y_offset_inches PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#if defined(PNG_pHYs_SUPPORTED)
+PNG_EXTERN png_uint_32 png_get_pHYs_dpi PNGARG((png_structp png_ptr,
+png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
+#endif /* PNG_pHYs_SUPPORTED */
+#endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
+
+/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
+
+#endif /* PNG_INTERNAL */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PNG_VERSION_INFO_ONLY */
+/* do not put anything past this line */
+#endif /* PNG_H */
diff --git a/src/libpng/pngconf.h b/src/libpng/pngconf.h
new file mode 100644
index 0000000..64f3ff0
--- /dev/null
+++ b/src/libpng/pngconf.h
@@ -0,0 +1,1483 @@
+
+/* pngconf.h - machine configurable file for libpng
+ *
+ * libpng version 1.2.22 - October 13, 2007
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+/* Any machine specific code is near the front of this file, so if you
+ * are configuring libpng for a machine, you may want to read the section
+ * starting here down to where it starts to typedef png_color, png_text,
+ * and png_info.
+ */
+
+#ifndef PNGCONF_H
+#define PNGCONF_H
+
+#define PNG_1_2_X
+
+/*
+ * PNG_USER_CONFIG has to be defined on the compiler command line. This
+ * includes the resource compiler for Windows DLL configurations.
+ */
+#ifdef PNG_USER_CONFIG
+# ifndef PNG_USER_PRIVATEBUILD
+# define PNG_USER_PRIVATEBUILD
+# endif
+#include "pngusr.h"
+#endif
+
+/* PNG_CONFIGURE_LIBPNG is set by the "configure" script. */
+#ifdef PNG_CONFIGURE_LIBPNG
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#endif
+
+/*
+ * Added at libpng-1.2.8
+ *
+ * If you create a private DLL you need to define in "pngusr.h" the followings:
+ * #define PNG_USER_PRIVATEBUILD <Describes by whom and why this version of
+ * the DLL was built>
+ * e.g. #define PNG_USER_PRIVATEBUILD "Build by MyCompany for xyz reasons."
+ * #define PNG_USER_DLLFNAME_POSTFIX <two-letter postfix that serve to
+ * distinguish your DLL from those of the official release. These
+ * correspond to the trailing letters that come after the version
+ * number and must match your private DLL name>
+ * e.g. // private DLL "libpng13gx.dll"
+ * #define PNG_USER_DLLFNAME_POSTFIX "gx"
+ *
+ * The following macros are also at your disposal if you want to complete the
+ * DLL VERSIONINFO structure.
+ * - PNG_USER_VERSIONINFO_COMMENTS
+ * - PNG_USER_VERSIONINFO_COMPANYNAME
+ * - PNG_USER_VERSIONINFO_LEGALTRADEMARKS
+ */
+
+#ifdef __STDC__
+#ifdef SPECIALBUILD
+# pragma message("PNG_LIBPNG_SPECIALBUILD (and deprecated SPECIALBUILD)\
+ are now LIBPNG reserved macros. Use PNG_USER_PRIVATEBUILD instead.")
+#endif
+
+#ifdef PRIVATEBUILD
+# pragma message("PRIVATEBUILD is deprecated.\
+ Use PNG_USER_PRIVATEBUILD instead.")
+# define PNG_USER_PRIVATEBUILD PRIVATEBUILD
+#endif
+#endif /* __STDC__ */
+
+#ifndef PNG_VERSION_INFO_ONLY
+
+/* End of material added to libpng-1.2.8 */
+
+/* Added at libpng-1.2.19, removed at libpng-1.2.20 because it caused trouble
+ Restored at libpng-1.2.21 */
+#if !defined(PNG_NO_WARN_UNINITIALIZED_ROW) && \
+ !defined(PNG_WARN_UNINITIALIZED_ROW)
+# define PNG_WARN_UNINITIALIZED_ROW 1
+#endif
+/* End of material added at libpng-1.2.19/1.2.21 */
+
+/* This is the size of the compression buffer, and thus the size of
+ * an IDAT chunk. Make this whatever size you feel is best for your
+ * machine. One of these will be allocated per png_struct. When this
+ * is full, it writes the data to the disk, and does some other
+ * calculations. Making this an extremely small size will slow
+ * the library down, but you may want to experiment to determine
+ * where it becomes significant, if you are concerned with memory
+ * usage. Note that zlib allocates at least 32Kb also. For readers,
+ * this describes the size of the buffer available to read the data in.
+ * Unless this gets smaller than the size of a row (compressed),
+ * it should not make much difference how big this is.
+ */
+
+#ifndef PNG_ZBUF_SIZE
+# define PNG_ZBUF_SIZE 8192
+#endif
+
+/* Enable if you want a write-only libpng */
+
+#ifndef PNG_NO_READ_SUPPORTED
+# define PNG_READ_SUPPORTED
+#endif
+
+/* Enable if you want a read-only libpng */
+
+#ifndef PNG_NO_WRITE_SUPPORTED
+# define PNG_WRITE_SUPPORTED
+#endif
+
+/* Enabled by default in 1.2.0. You can disable this if you don't need to
+ support PNGs that are embedded in MNG datastreams */
+#if !defined(PNG_1_0_X) && !defined(PNG_NO_MNG_FEATURES)
+# ifndef PNG_MNG_FEATURES_SUPPORTED
+# define PNG_MNG_FEATURES_SUPPORTED
+# endif
+#endif
+
+#ifndef PNG_NO_FLOATING_POINT_SUPPORTED
+# ifndef PNG_FLOATING_POINT_SUPPORTED
+# define PNG_FLOATING_POINT_SUPPORTED
+# endif
+#endif
+
+/* If you are running on a machine where you cannot allocate more
+ * than 64K of memory at once, uncomment this. While libpng will not
+ * normally need that much memory in a chunk (unless you load up a very
+ * large file), zlib needs to know how big of a chunk it can use, and
+ * libpng thus makes sure to check any memory allocation to verify it
+ * will fit into memory.
+#define PNG_MAX_MALLOC_64K
+ */
+#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
+# define PNG_MAX_MALLOC_64K
+#endif
+
+/* Special munging to support doing things the 'cygwin' way:
+ * 'Normal' png-on-win32 defines/defaults:
+ * PNG_BUILD_DLL -- building dll
+ * PNG_USE_DLL -- building an application, linking to dll
+ * (no define) -- building static library, or building an
+ * application and linking to the static lib
+ * 'Cygwin' defines/defaults:
+ * PNG_BUILD_DLL -- (ignored) building the dll
+ * (no define) -- (ignored) building an application, linking to the dll
+ * PNG_STATIC -- (ignored) building the static lib, or building an
+ * application that links to the static lib.
+ * ALL_STATIC -- (ignored) building various static libs, or building an
+ * application that links to the static libs.
+ * Thus,
+ * a cygwin user should define either PNG_BUILD_DLL or PNG_STATIC, and
+ * this bit of #ifdefs will define the 'correct' config variables based on
+ * that. If a cygwin user *wants* to define 'PNG_USE_DLL' that's okay, but
+ * unnecessary.
+ *
+ * Also, the precedence order is:
+ * ALL_STATIC (since we can't #undef something outside our namespace)
+ * PNG_BUILD_DLL
+ * PNG_STATIC
+ * (nothing) == PNG_USE_DLL
+ *
+ * CYGWIN (2002-01-20): The preceding is now obsolete. With the advent
+ * of auto-import in binutils, we no longer need to worry about
+ * __declspec(dllexport) / __declspec(dllimport) and friends. Therefore,
+ * we don't need to worry about PNG_STATIC or ALL_STATIC when it comes
+ * to __declspec() stuff. However, we DO need to worry about
+ * PNG_BUILD_DLL and PNG_STATIC because those change some defaults
+ * such as CONSOLE_IO and whether GLOBAL_ARRAYS are allowed.
+ */
+#if defined(__CYGWIN__)
+# if defined(ALL_STATIC)
+# if defined(PNG_BUILD_DLL)
+# undef PNG_BUILD_DLL
+# endif
+# if defined(PNG_USE_DLL)
+# undef PNG_USE_DLL
+# endif
+# if defined(PNG_DLL)
+# undef PNG_DLL
+# endif
+# if !defined(PNG_STATIC)
+# define PNG_STATIC
+# endif
+# else
+# if defined (PNG_BUILD_DLL)
+# if defined(PNG_STATIC)
+# undef PNG_STATIC
+# endif
+# if defined(PNG_USE_DLL)
+# undef PNG_USE_DLL
+# endif
+# if !defined(PNG_DLL)
+# define PNG_DLL
+# endif
+# else
+# if defined(PNG_STATIC)
+# if defined(PNG_USE_DLL)
+# undef PNG_USE_DLL
+# endif
+# if defined(PNG_DLL)
+# undef PNG_DLL
+# endif
+# else
+# if !defined(PNG_USE_DLL)
+# define PNG_USE_DLL
+# endif
+# if !defined(PNG_DLL)
+# define PNG_DLL
+# endif
+# endif
+# endif
+# endif
+#endif
+
+/* This protects us against compilers that run on a windowing system
+ * and thus don't have or would rather us not use the stdio types:
+ * stdin, stdout, and stderr. The only one currently used is stderr
+ * in png_error() and png_warning(). #defining PNG_NO_CONSOLE_IO will
+ * prevent these from being compiled and used. #defining PNG_NO_STDIO
+ * will also prevent these, plus will prevent the entire set of stdio
+ * macros and functions (FILE *, printf, etc.) from being compiled and used,
+ * unless (PNG_DEBUG > 0) has been #defined.
+ *
+ * #define PNG_NO_CONSOLE_IO
+ * #define PNG_NO_STDIO
+ */
+
+#if defined(_WIN32_WCE)
+# include <windows.h>
+ /* Console I/O functions are not supported on WindowsCE */
+# define PNG_NO_CONSOLE_IO
+# ifdef PNG_DEBUG
+# undef PNG_DEBUG
+# endif
+#endif
+
+#ifdef PNG_BUILD_DLL
+# ifndef PNG_CONSOLE_IO_SUPPORTED
+# ifndef PNG_NO_CONSOLE_IO
+# define PNG_NO_CONSOLE_IO
+# endif
+# endif
+#endif
+
+# ifdef PNG_NO_STDIO
+# ifndef PNG_NO_CONSOLE_IO
+# define PNG_NO_CONSOLE_IO
+# endif
+# ifdef PNG_DEBUG
+# if (PNG_DEBUG > 0)
+# include <stdio.h>
+# endif
+# endif
+# else
+# if !defined(_WIN32_WCE)
+/* "stdio.h" functions are not supported on WindowsCE */
+# include <stdio.h>
+# endif
+# endif
+
+/* This macro protects us against machines that don't have function
+ * prototypes (ie K&R style headers). If your compiler does not handle
+ * function prototypes, define this macro and use the included ansi2knr.
+ * I've always been able to use _NO_PROTO as the indicator, but you may
+ * need to drag the empty declaration out in front of here, or change the
+ * ifdef to suit your own needs.
+ */
+#ifndef PNGARG
+
+#ifdef OF /* zlib prototype munger */
+# define PNGARG(arglist) OF(arglist)
+#else
+
+#ifdef _NO_PROTO
+# define PNGARG(arglist) ()
+# ifndef PNG_TYPECAST_NULL
+# define PNG_TYPECAST_NULL
+# endif
+#else
+# define PNGARG(arglist) arglist
+#endif /* _NO_PROTO */
+
+
+#endif /* OF */
+
+#endif /* PNGARG */
+
+/* Try to determine if we are compiling on a Mac. Note that testing for
+ * just __MWERKS__ is not good enough, because the Codewarrior is now used
+ * on non-Mac platforms.
+ */
+#ifndef MACOS
+# if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
+ defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
+# define MACOS
+# endif
+#endif
+
+/* enough people need this for various reasons to include it here */
+#if !defined(MACOS) && !defined(RISCOS) && !defined(_WIN32_WCE)
+# include <sys/types.h>
+#endif
+
+#if !defined(PNG_SETJMP_NOT_SUPPORTED) && !defined(PNG_NO_SETJMP_SUPPORTED)
+# define PNG_SETJMP_SUPPORTED
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+/* This is an attempt to force a single setjmp behaviour on Linux. If
+ * the X config stuff didn't define _BSD_SOURCE we wouldn't need this.
+ */
+
+# ifdef __linux__
+# ifdef _BSD_SOURCE
+# define PNG_SAVE_BSD_SOURCE
+# undef _BSD_SOURCE
+# endif
+# ifdef _SETJMP_H
+ /* If you encounter a compiler error here, see the explanation
+ * near the end of INSTALL.
+ */
+ __png.h__ already includes setjmp.h;
+ __dont__ include it again.;
+# endif
+# endif /* __linux__ */
+
+ /* include setjmp.h for error handling */
+# include <setjmp.h>
+
+# ifdef __linux__
+# ifdef PNG_SAVE_BSD_SOURCE
+# define _BSD_SOURCE
+# undef PNG_SAVE_BSD_SOURCE
+# endif
+# endif /* __linux__ */
+#endif /* PNG_SETJMP_SUPPORTED */
+
+#ifdef BSD
+# include <strings.h>
+#else
+# include <string.h>
+#endif
+
+/* Other defines for things like memory and the like can go here. */
+#ifdef PNG_INTERNAL
+
+#include <stdlib.h>
+
+/* The functions exported by PNG_EXTERN are PNG_INTERNAL functions, which
+ * aren't usually used outside the library (as far as I know), so it is
+ * debatable if they should be exported at all. In the future, when it is
+ * possible to have run-time registry of chunk-handling functions, some of
+ * these will be made available again.
+#define PNG_EXTERN extern
+ */
+#define PNG_EXTERN
+
+/* Other defines specific to compilers can go here. Try to keep
+ * them inside an appropriate ifdef/endif pair for portability.
+ */
+
+#if defined(PNG_FLOATING_POINT_SUPPORTED)
+# if defined(MACOS)
+ /* We need to check that <math.h> hasn't already been included earlier
+ * as it seems it doesn't agree with <fp.h>, yet we should really use
+ * <fp.h> if possible.
+ */
+# if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
+# include <fp.h>
+# endif
+# else
+# include <math.h>
+# endif
+# if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
+ /* Amiga SAS/C: We must include builtin FPU functions when compiling using
+ * MATH=68881
+ */
+# include <m68881.h>
+# endif
+#endif
+
+/* Codewarrior on NT has linking problems without this. */
+#if (defined(__MWERKS__) && defined(WIN32)) || defined(__STDC__)
+# define PNG_ALWAYS_EXTERN
+#endif
+
+/* This provides the non-ANSI (far) memory allocation routines. */
+#if defined(__TURBOC__) && defined(__MSDOS__)
+# include <mem.h>
+# include <alloc.h>
+#endif
+
+/* I have no idea why is this necessary... */
+#if defined(_MSC_VER) && (defined(WIN32) || defined(_Windows) || \
+ defined(_WINDOWS) || defined(_WIN32) || defined(__WIN32__))
+# include <malloc.h>
+#endif
+
+/* This controls how fine the dithering gets. As this allocates
+ * a largish chunk of memory (32K), those who are not as concerned
+ * with dithering quality can decrease some or all of these.
+ */
+#ifndef PNG_DITHER_RED_BITS
+# define PNG_DITHER_RED_BITS 5
+#endif
+#ifndef PNG_DITHER_GREEN_BITS
+# define PNG_DITHER_GREEN_BITS 5
+#endif
+#ifndef PNG_DITHER_BLUE_BITS
+# define PNG_DITHER_BLUE_BITS 5
+#endif
+
+/* This controls how fine the gamma correction becomes when you
+ * are only interested in 8 bits anyway. Increasing this value
+ * results in more memory being used, and more pow() functions
+ * being called to fill in the gamma tables. Don't set this value
+ * less then 8, and even that may not work (I haven't tested it).
+ */
+
+#ifndef PNG_MAX_GAMMA_8
+# define PNG_MAX_GAMMA_8 11
+#endif
+
+/* This controls how much a difference in gamma we can tolerate before
+ * we actually start doing gamma conversion.
+ */
+#ifndef PNG_GAMMA_THRESHOLD
+# define PNG_GAMMA_THRESHOLD 0.05
+#endif
+
+#endif /* PNG_INTERNAL */
+
+/* The following uses const char * instead of char * for error
+ * and warning message functions, so some compilers won't complain.
+ * If you do not want to use const, define PNG_NO_CONST here.
+ */
+
+#ifndef PNG_NO_CONST
+# define PNG_CONST const
+#else
+# define PNG_CONST
+#endif
+
+/* The following defines give you the ability to remove code from the
+ * library that you will not be using. I wish I could figure out how to
+ * automate this, but I can't do that without making it seriously hard
+ * on the users. So if you are not using an ability, change the #define
+ * to and #undef, and that part of the library will not be compiled. If
+ * your linker can't find a function, you may want to make sure the
+ * ability is defined here. Some of these depend upon some others being
+ * defined. I haven't figured out all the interactions here, so you may
+ * have to experiment awhile to get everything to compile. If you are
+ * creating or using a shared library, you probably shouldn't touch this,
+ * as it will affect the size of the structures, and this will cause bad
+ * things to happen if the library and/or application ever change.
+ */
+
+/* Any features you will not be using can be undef'ed here */
+
+/* GR-P, 0.96a: Set "*TRANSFORMS_SUPPORTED as default but allow user
+ * to turn it off with "*TRANSFORMS_NOT_SUPPORTED" or *PNG_NO_*_TRANSFORMS
+ * on the compile line, then pick and choose which ones to define without
+ * having to edit this file. It is safe to use the *TRANSFORMS_NOT_SUPPORTED
+ * if you only want to have a png-compliant reader/writer but don't need
+ * any of the extra transformations. This saves about 80 kbytes in a
+ * typical installation of the library. (PNG_NO_* form added in version
+ * 1.0.1c, for consistency)
+ */
+
+/* The size of the png_text structure changed in libpng-1.0.6 when
+ * iTXt support was added. iTXt support was turned off by default through
+ * libpng-1.2.x, to support old apps that malloc the png_text structure
+ * instead of calling png_set_text() and letting libpng malloc it. It
+ * was turned on by default in libpng-1.3.0.
+ */
+
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+# ifndef PNG_NO_iTXt_SUPPORTED
+# define PNG_NO_iTXt_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_iTXt
+# define PNG_NO_READ_iTXt
+# endif
+# ifndef PNG_NO_WRITE_iTXt
+# define PNG_NO_WRITE_iTXt
+# endif
+#endif
+
+#if !defined(PNG_NO_iTXt_SUPPORTED)
+# if !defined(PNG_READ_iTXt_SUPPORTED) && !defined(PNG_NO_READ_iTXt)
+# define PNG_READ_iTXt
+# endif
+# if !defined(PNG_WRITE_iTXt_SUPPORTED) && !defined(PNG_NO_WRITE_iTXt)
+# define PNG_WRITE_iTXt
+# endif
+#endif
+
+/* The following support, added after version 1.0.0, can be turned off here en
+ * masse by defining PNG_LEGACY_SUPPORTED in case you need binary compatibility
+ * with old applications that require the length of png_struct and png_info
+ * to remain unchanged.
+ */
+
+#ifdef PNG_LEGACY_SUPPORTED
+# define PNG_NO_FREE_ME
+# define PNG_NO_READ_UNKNOWN_CHUNKS
+# define PNG_NO_WRITE_UNKNOWN_CHUNKS
+# define PNG_NO_READ_USER_CHUNKS
+# define PNG_NO_READ_iCCP
+# define PNG_NO_WRITE_iCCP
+# define PNG_NO_READ_iTXt
+# define PNG_NO_WRITE_iTXt
+# define PNG_NO_READ_sCAL
+# define PNG_NO_WRITE_sCAL
+# define PNG_NO_READ_sPLT
+# define PNG_NO_WRITE_sPLT
+# define PNG_NO_INFO_IMAGE
+# define PNG_NO_READ_RGB_TO_GRAY
+# define PNG_NO_READ_USER_TRANSFORM
+# define PNG_NO_WRITE_USER_TRANSFORM
+# define PNG_NO_USER_MEM
+# define PNG_NO_READ_EMPTY_PLTE
+# define PNG_NO_MNG_FEATURES
+# define PNG_NO_FIXED_POINT_SUPPORTED
+#endif
+
+/* Ignore attempt to turn off both floating and fixed point support */
+#if !defined(PNG_FLOATING_POINT_SUPPORTED) || \
+ !defined(PNG_NO_FIXED_POINT_SUPPORTED)
+# define PNG_FIXED_POINT_SUPPORTED
+#endif
+
+#ifndef PNG_NO_FREE_ME
+# define PNG_FREE_ME_SUPPORTED
+#endif
+
+#if defined(PNG_READ_SUPPORTED)
+
+#if !defined(PNG_READ_TRANSFORMS_NOT_SUPPORTED) && \
+ !defined(PNG_NO_READ_TRANSFORMS)
+# define PNG_READ_TRANSFORMS_SUPPORTED
+#endif
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+# ifndef PNG_NO_READ_EXPAND
+# define PNG_READ_EXPAND_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_SHIFT
+# define PNG_READ_SHIFT_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_PACK
+# define PNG_READ_PACK_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_BGR
+# define PNG_READ_BGR_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_SWAP
+# define PNG_READ_SWAP_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_PACKSWAP
+# define PNG_READ_PACKSWAP_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_INVERT
+# define PNG_READ_INVERT_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_DITHER
+# define PNG_READ_DITHER_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_BACKGROUND
+# define PNG_READ_BACKGROUND_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_16_TO_8
+# define PNG_READ_16_TO_8_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_FILLER
+# define PNG_READ_FILLER_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_GAMMA
+# define PNG_READ_GAMMA_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_GRAY_TO_RGB
+# define PNG_READ_GRAY_TO_RGB_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_SWAP_ALPHA
+# define PNG_READ_SWAP_ALPHA_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_INVERT_ALPHA
+# define PNG_READ_INVERT_ALPHA_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_STRIP_ALPHA
+# define PNG_READ_STRIP_ALPHA_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_USER_TRANSFORM
+# define PNG_READ_USER_TRANSFORM_SUPPORTED
+# endif
+# ifndef PNG_NO_READ_RGB_TO_GRAY
+# define PNG_READ_RGB_TO_GRAY_SUPPORTED
+# endif
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
+
+#if !defined(PNG_NO_PROGRESSIVE_READ) && \
+ !defined(PNG_PROGRESSIVE_READ_SUPPORTED) /* if you don't do progressive */
+# define PNG_PROGRESSIVE_READ_SUPPORTED /* reading. This is not talking */
+#endif /* about interlacing capability! You'll */
+ /* still have interlacing unless you change the following line: */
+
+#define PNG_READ_INTERLACING_SUPPORTED /* required in PNG-compliant decoders */
+
+#ifndef PNG_NO_READ_COMPOSITE_NODIV
+# ifndef PNG_NO_READ_COMPOSITED_NODIV /* libpng-1.0.x misspelling */
+# define PNG_READ_COMPOSITE_NODIV_SUPPORTED /* well tested on Intel, SGI */
+# endif
+#endif
+
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+/* Deprecated, will be removed from version 2.0.0.
+ Use PNG_MNG_FEATURES_SUPPORTED instead. */
+#ifndef PNG_NO_READ_EMPTY_PLTE
+# define PNG_READ_EMPTY_PLTE_SUPPORTED
+#endif
+#endif
+
+#endif /* PNG_READ_SUPPORTED */
+
+#if defined(PNG_WRITE_SUPPORTED)
+
+# if !defined(PNG_WRITE_TRANSFORMS_NOT_SUPPORTED) && \
+ !defined(PNG_NO_WRITE_TRANSFORMS)
+# define PNG_WRITE_TRANSFORMS_SUPPORTED
+#endif
+
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+# ifndef PNG_NO_WRITE_SHIFT
+# define PNG_WRITE_SHIFT_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_PACK
+# define PNG_WRITE_PACK_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_BGR
+# define PNG_WRITE_BGR_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_SWAP
+# define PNG_WRITE_SWAP_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_PACKSWAP
+# define PNG_WRITE_PACKSWAP_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_INVERT
+# define PNG_WRITE_INVERT_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_FILLER
+# define PNG_WRITE_FILLER_SUPPORTED /* same as WRITE_STRIP_ALPHA */
+# endif
+# ifndef PNG_NO_WRITE_SWAP_ALPHA
+# define PNG_WRITE_SWAP_ALPHA_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_INVERT_ALPHA
+# define PNG_WRITE_INVERT_ALPHA_SUPPORTED
+# endif
+# ifndef PNG_NO_WRITE_USER_TRANSFORM
+# define PNG_WRITE_USER_TRANSFORM_SUPPORTED
+# endif
+#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
+
+#if !defined(PNG_NO_WRITE_INTERLACING_SUPPORTED) && \
+ !defined(PNG_WRITE_INTERLACING_SUPPORTED)
+#define PNG_WRITE_INTERLACING_SUPPORTED /* not required for PNG-compliant
+ encoders, but can cause trouble
+ if left undefined */
+#endif
+
+#if !defined(PNG_NO_WRITE_WEIGHTED_FILTER) && \
+ !defined(PNG_WRITE_WEIGHTED_FILTER) && \
+ defined(PNG_FLOATING_POINT_SUPPORTED)
+# define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+#endif
+
+#ifndef PNG_NO_WRITE_FLUSH
+# define PNG_WRITE_FLUSH_SUPPORTED
+#endif
+
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+/* Deprecated, see PNG_MNG_FEATURES_SUPPORTED, above */
+#ifndef PNG_NO_WRITE_EMPTY_PLTE
+# define PNG_WRITE_EMPTY_PLTE_SUPPORTED
+#endif
+#endif
+
+#endif /* PNG_WRITE_SUPPORTED */
+
+#ifndef PNG_1_0_X
+# ifndef PNG_NO_ERROR_NUMBERS
+# define PNG_ERROR_NUMBERS_SUPPORTED
+# endif
+#endif /* PNG_1_0_X */
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+# ifndef PNG_NO_USER_TRANSFORM_PTR
+# define PNG_USER_TRANSFORM_PTR_SUPPORTED
+# endif
+#endif
+
+#ifndef PNG_NO_STDIO
+# define PNG_TIME_RFC1123_SUPPORTED
+#endif
+
+/* This adds extra functions in pngget.c for accessing data from the
+ * info pointer (added in version 0.99)
+ * png_get_image_width()
+ * png_get_image_height()
+ * png_get_bit_depth()
+ * png_get_color_type()
+ * png_get_compression_type()
+ * png_get_filter_type()
+ * png_get_interlace_type()
+ * png_get_pixel_aspect_ratio()
+ * png_get_pixels_per_meter()
+ * png_get_x_offset_pixels()
+ * png_get_y_offset_pixels()
+ * png_get_x_offset_microns()
+ * png_get_y_offset_microns()
+ */
+#if !defined(PNG_NO_EASY_ACCESS) && !defined(PNG_EASY_ACCESS_SUPPORTED)
+# define PNG_EASY_ACCESS_SUPPORTED
+#endif
+
+/* PNG_ASSEMBLER_CODE was enabled by default in version 1.2.0
+ * and removed from version 1.2.20. The following will be removed
+ * from libpng-1.4.0
+*/
+
+#if defined(PNG_READ_SUPPORTED) && !defined(PNG_NO_OPTIMIZED_CODE)
+# ifndef PNG_OPTIMIZED_CODE_SUPPORTED
+# define PNG_OPTIMIZED_CODE_SUPPORTED
+# endif
+#endif
+
+#if defined(PNG_READ_SUPPORTED) && !defined(PNG_NO_ASSEMBLER_CODE)
+# ifndef PNG_ASSEMBLER_CODE_SUPPORTED
+# define PNG_ASSEMBLER_CODE_SUPPORTED
+# endif
+
+# if defined(__GNUC__) && defined(__x86_64__) && (__GNUC__ < 4)
+ /* work around 64-bit gcc compiler bugs in gcc-3.x */
+# if !defined(PNG_MMX_CODE_SUPPORTED) && !defined(PNG_NO_MMX_CODE)
+# define PNG_NO_MMX_CODE
+# endif
+# endif
+
+# if defined(__APPLE__)
+# if !defined(PNG_MMX_CODE_SUPPORTED) && !defined(PNG_NO_MMX_CODE)
+# define PNG_NO_MMX_CODE
+# endif
+# endif
+
+# if (defined(__MWERKS__) && ((__MWERKS__ < 0x0900) || macintosh))
+# if !defined(PNG_MMX_CODE_SUPPORTED) && !defined(PNG_NO_MMX_CODE)
+# define PNG_NO_MMX_CODE
+# endif
+# endif
+
+# if !defined(PNG_MMX_CODE_SUPPORTED) && !defined(PNG_NO_MMX_CODE)
+# define PNG_MMX_CODE_SUPPORTED
+# endif
+
+#endif
+/* end of obsolete code to be removed from libpng-1.4.0 */
+
+#if !defined(PNG_1_0_X)
+#if !defined(PNG_NO_USER_MEM) && !defined(PNG_USER_MEM_SUPPORTED)
+# define PNG_USER_MEM_SUPPORTED
+#endif
+#endif /* PNG_1_0_X */
+
+/* Added at libpng-1.2.6 */
+#if !defined(PNG_1_0_X)
+#ifndef PNG_SET_USER_LIMITS_SUPPORTED
+#if !defined(PNG_NO_SET_USER_LIMITS) && !defined(PNG_SET_USER_LIMITS_SUPPORTED)
+# define PNG_SET_USER_LIMITS_SUPPORTED
+#endif
+#endif
+#endif /* PNG_1_0_X */
+
+/* Added at libpng-1.0.16 and 1.2.6. To accept all valid PNGS no matter
+ * how large, set these limits to 0x7fffffffL
+ */
+#ifndef PNG_USER_WIDTH_MAX
+# define PNG_USER_WIDTH_MAX 1000000L
+#endif
+#ifndef PNG_USER_HEIGHT_MAX
+# define PNG_USER_HEIGHT_MAX 1000000L
+#endif
+
+/* These are currently experimental features, define them if you want */
+
+/* very little testing */
+/*
+#ifdef PNG_READ_SUPPORTED
+# ifndef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+# define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+# endif
+#endif
+*/
+
+/* This is only for PowerPC big-endian and 680x0 systems */
+/* some testing */
+/*
+#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
+# define PNG_READ_BIG_ENDIAN_SUPPORTED
+#endif
+*/
+
+/* Buggy compilers (e.g., gcc 2.7.2.2) need this */
+/*
+#define PNG_NO_POINTER_INDEXING
+*/
+
+/* These functions are turned off by default, as they will be phased out. */
+/*
+#define PNG_USELESS_TESTS_SUPPORTED
+#define PNG_CORRECT_PALETTE_SUPPORTED
+*/
+
+/* Any chunks you are not interested in, you can undef here. The
+ * ones that allocate memory may be expecially important (hIST,
+ * tEXt, zTXt, tRNS, pCAL). Others will just save time and make png_info
+ * a bit smaller.
+ */
+
+#if defined(PNG_READ_SUPPORTED) && \
+ !defined(PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
+ !defined(PNG_NO_READ_ANCILLARY_CHUNKS)
+# define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+
+#if defined(PNG_WRITE_SUPPORTED) && \
+ !defined(PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
+ !defined(PNG_NO_WRITE_ANCILLARY_CHUNKS)
+# define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+
+#ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+
+#ifdef PNG_NO_READ_TEXT
+# define PNG_NO_READ_iTXt
+# define PNG_NO_READ_tEXt
+# define PNG_NO_READ_zTXt
+#endif
+#ifndef PNG_NO_READ_bKGD
+# define PNG_READ_bKGD_SUPPORTED
+# define PNG_bKGD_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_cHRM
+# define PNG_READ_cHRM_SUPPORTED
+# define PNG_cHRM_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_gAMA
+# define PNG_READ_gAMA_SUPPORTED
+# define PNG_gAMA_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_hIST
+# define PNG_READ_hIST_SUPPORTED
+# define PNG_hIST_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_iCCP
+# define PNG_READ_iCCP_SUPPORTED
+# define PNG_iCCP_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_iTXt
+# ifndef PNG_READ_iTXt_SUPPORTED
+# define PNG_READ_iTXt_SUPPORTED
+# endif
+# ifndef PNG_iTXt_SUPPORTED
+# define PNG_iTXt_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_READ_oFFs
+# define PNG_READ_oFFs_SUPPORTED
+# define PNG_oFFs_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_pCAL
+# define PNG_READ_pCAL_SUPPORTED
+# define PNG_pCAL_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sCAL
+# define PNG_READ_sCAL_SUPPORTED
+# define PNG_sCAL_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_pHYs
+# define PNG_READ_pHYs_SUPPORTED
+# define PNG_pHYs_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sBIT
+# define PNG_READ_sBIT_SUPPORTED
+# define PNG_sBIT_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sPLT
+# define PNG_READ_sPLT_SUPPORTED
+# define PNG_sPLT_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sRGB
+# define PNG_READ_sRGB_SUPPORTED
+# define PNG_sRGB_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tEXt
+# define PNG_READ_tEXt_SUPPORTED
+# define PNG_tEXt_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tIME
+# define PNG_READ_tIME_SUPPORTED
+# define PNG_tIME_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tRNS
+# define PNG_READ_tRNS_SUPPORTED
+# define PNG_tRNS_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_zTXt
+# define PNG_READ_zTXt_SUPPORTED
+# define PNG_zTXt_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_UNKNOWN_CHUNKS
+# define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+# ifndef PNG_UNKNOWN_CHUNKS_SUPPORTED
+# define PNG_UNKNOWN_CHUNKS_SUPPORTED
+# endif
+# ifndef PNG_NO_HANDLE_AS_UNKNOWN
+# define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+# endif
+#endif
+#if !defined(PNG_NO_READ_USER_CHUNKS) && \
+ defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+# define PNG_READ_USER_CHUNKS_SUPPORTED
+# define PNG_USER_CHUNKS_SUPPORTED
+# ifdef PNG_NO_READ_UNKNOWN_CHUNKS
+# undef PNG_NO_READ_UNKNOWN_CHUNKS
+# endif
+# ifdef PNG_NO_HANDLE_AS_UNKNOWN
+# undef PNG_NO_HANDLE_AS_UNKNOWN
+# endif
+#endif
+#ifndef PNG_NO_READ_OPT_PLTE
+# define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the */
+#endif /* optional PLTE chunk in RGB and RGBA images */
+#if defined(PNG_READ_iTXt_SUPPORTED) || defined(PNG_READ_tEXt_SUPPORTED) || \
+ defined(PNG_READ_zTXt_SUPPORTED)
+# define PNG_READ_TEXT_SUPPORTED
+# define PNG_TEXT_SUPPORTED
+#endif
+
+#endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */
+
+#ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+
+#ifdef PNG_NO_WRITE_TEXT
+# define PNG_NO_WRITE_iTXt
+# define PNG_NO_WRITE_tEXt
+# define PNG_NO_WRITE_zTXt
+#endif
+#ifndef PNG_NO_WRITE_bKGD
+# define PNG_WRITE_bKGD_SUPPORTED
+# ifndef PNG_bKGD_SUPPORTED
+# define PNG_bKGD_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_cHRM
+# define PNG_WRITE_cHRM_SUPPORTED
+# ifndef PNG_cHRM_SUPPORTED
+# define PNG_cHRM_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_gAMA
+# define PNG_WRITE_gAMA_SUPPORTED
+# ifndef PNG_gAMA_SUPPORTED
+# define PNG_gAMA_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_hIST
+# define PNG_WRITE_hIST_SUPPORTED
+# ifndef PNG_hIST_SUPPORTED
+# define PNG_hIST_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_iCCP
+# define PNG_WRITE_iCCP_SUPPORTED
+# ifndef PNG_iCCP_SUPPORTED
+# define PNG_iCCP_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_iTXt
+# ifndef PNG_WRITE_iTXt_SUPPORTED
+# define PNG_WRITE_iTXt_SUPPORTED
+# endif
+# ifndef PNG_iTXt_SUPPORTED
+# define PNG_iTXt_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_oFFs
+# define PNG_WRITE_oFFs_SUPPORTED
+# ifndef PNG_oFFs_SUPPORTED
+# define PNG_oFFs_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_pCAL
+# define PNG_WRITE_pCAL_SUPPORTED
+# ifndef PNG_pCAL_SUPPORTED
+# define PNG_pCAL_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_sCAL
+# define PNG_WRITE_sCAL_SUPPORTED
+# ifndef PNG_sCAL_SUPPORTED
+# define PNG_sCAL_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_pHYs
+# define PNG_WRITE_pHYs_SUPPORTED
+# ifndef PNG_pHYs_SUPPORTED
+# define PNG_pHYs_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_sBIT
+# define PNG_WRITE_sBIT_SUPPORTED
+# ifndef PNG_sBIT_SUPPORTED
+# define PNG_sBIT_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_sPLT
+# define PNG_WRITE_sPLT_SUPPORTED
+# ifndef PNG_sPLT_SUPPORTED
+# define PNG_sPLT_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_sRGB
+# define PNG_WRITE_sRGB_SUPPORTED
+# ifndef PNG_sRGB_SUPPORTED
+# define PNG_sRGB_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_tEXt
+# define PNG_WRITE_tEXt_SUPPORTED
+# ifndef PNG_tEXt_SUPPORTED
+# define PNG_tEXt_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_tIME
+# define PNG_WRITE_tIME_SUPPORTED
+# ifndef PNG_tIME_SUPPORTED
+# define PNG_tIME_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_tRNS
+# define PNG_WRITE_tRNS_SUPPORTED
+# ifndef PNG_tRNS_SUPPORTED
+# define PNG_tRNS_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_zTXt
+# define PNG_WRITE_zTXt_SUPPORTED
+# ifndef PNG_zTXt_SUPPORTED
+# define PNG_zTXt_SUPPORTED
+# endif
+#endif
+#ifndef PNG_NO_WRITE_UNKNOWN_CHUNKS
+# define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+# ifndef PNG_UNKNOWN_CHUNKS_SUPPORTED
+# define PNG_UNKNOWN_CHUNKS_SUPPORTED
+# endif
+# ifndef PNG_NO_HANDLE_AS_UNKNOWN
+# ifndef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+# define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+# endif
+# endif
+#endif
+#if defined(PNG_WRITE_iTXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
+ defined(PNG_WRITE_zTXt_SUPPORTED)
+# define PNG_WRITE_TEXT_SUPPORTED
+# ifndef PNG_TEXT_SUPPORTED
+# define PNG_TEXT_SUPPORTED
+# endif
+#endif
+
+#endif /* PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED */
+
+/* Turn this off to disable png_read_png() and
+ * png_write_png() and leave the row_pointers member
+ * out of the info structure.
+ */
+#ifndef PNG_NO_INFO_IMAGE
+# define PNG_INFO_IMAGE_SUPPORTED
+#endif
+
+/* need the time information for reading tIME chunks */
+#if defined(PNG_tIME_SUPPORTED)
+# if !defined(_WIN32_WCE)
+ /* "time.h" functions are not supported on WindowsCE */
+# include <time.h>
+# endif
+#endif
+
+/* Some typedefs to get us started. These should be safe on most of the
+ * common platforms. The typedefs should be at least as large as the
+ * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
+ * don't have to be exactly that size. Some compilers dislike passing
+ * unsigned shorts as function parameters, so you may be better off using
+ * unsigned int for png_uint_16. Likewise, for 64-bit systems, you may
+ * want to have unsigned int for png_uint_32 instead of unsigned long.
+ */
+
+typedef unsigned int png_uint_32; /* IMLIB - changed long to int */
+typedef int png_int_32; /* IMLIB - changed long to int */
+typedef unsigned short png_uint_16;
+typedef short png_int_16;
+typedef unsigned char png_byte;
+
+/* This is usually size_t. It is typedef'ed just in case you need it to
+ change (I'm not sure if you will or not, so I thought I'd be safe) */
+#ifdef PNG_SIZE_T
+ typedef PNG_SIZE_T png_size_t;
+# define png_sizeof(x) png_convert_size(sizeof (x))
+#else
+ typedef size_t png_size_t;
+# define png_sizeof(x) sizeof (x)
+#endif
+
+/* The following is needed for medium model support. It cannot be in the
+ * PNG_INTERNAL section. Needs modification for other compilers besides
+ * MSC. Model independent support declares all arrays and pointers to be
+ * large using the far keyword. The zlib version used must also support
+ * model independent data. As of version zlib 1.0.4, the necessary changes
+ * have been made in zlib. The USE_FAR_KEYWORD define triggers other
+ * changes that are needed. (Tim Wegner)
+ */
+
+/* Separate compiler dependencies (problem here is that zlib.h always
+ defines FAR. (SJT) */
+#ifdef __BORLANDC__
+# if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
+# define LDATA 1
+# else
+# define LDATA 0
+# endif
+ /* GRR: why is Cygwin in here? Cygwin is not Borland C... */
+# if !defined(__WIN32__) && !defined(__FLAT__) && !defined(__CYGWIN__)
+# define PNG_MAX_MALLOC_64K
+# if (LDATA != 1)
+# ifndef FAR
+# define FAR __far
+# endif
+# define USE_FAR_KEYWORD
+# endif /* LDATA != 1 */
+ /* Possibly useful for moving data out of default segment.
+ * Uncomment it if you want. Could also define FARDATA as
+ * const if your compiler supports it. (SJT)
+# define FARDATA FAR
+ */
+# endif /* __WIN32__, __FLAT__, __CYGWIN__ */
+#endif /* __BORLANDC__ */
+
+
+/* Suggest testing for specific compiler first before testing for
+ * FAR. The Watcom compiler defines both __MEDIUM__ and M_I86MM,
+ * making reliance oncertain keywords suspect. (SJT)
+ */
+
+/* MSC Medium model */
+#if defined(FAR)
+# if defined(M_I86MM)
+# define USE_FAR_KEYWORD
+# define FARDATA FAR
+# include <dos.h>
+# endif
+#endif
+
+/* SJT: default case */
+#ifndef FAR
+# define FAR
+#endif
+
+/* At this point FAR is always defined */
+#ifndef FARDATA
+# define FARDATA
+#endif
+
+/* Typedef for floating-point numbers that are converted
+ to fixed-point with a multiple of 100,000, e.g., int_gamma */
+typedef png_int_32 png_fixed_point;
+
+/* Add typedefs for pointers */
+typedef void FAR * png_voidp;
+typedef png_byte FAR * png_bytep;
+typedef png_uint_32 FAR * png_uint_32p;
+typedef png_int_32 FAR * png_int_32p;
+typedef png_uint_16 FAR * png_uint_16p;
+typedef png_int_16 FAR * png_int_16p;
+typedef PNG_CONST char FAR * png_const_charp;
+typedef char FAR * png_charp;
+typedef png_fixed_point FAR * png_fixed_point_p;
+
+#ifndef PNG_NO_STDIO
+#if defined(_WIN32_WCE)
+typedef HANDLE png_FILE_p;
+#else
+typedef FILE * png_FILE_p;
+#endif
+#endif
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+typedef double FAR * png_doublep;
+#endif
+
+/* Pointers to pointers; i.e. arrays */
+typedef png_byte FAR * FAR * png_bytepp;
+typedef png_uint_32 FAR * FAR * png_uint_32pp;
+typedef png_int_32 FAR * FAR * png_int_32pp;
+typedef png_uint_16 FAR * FAR * png_uint_16pp;
+typedef png_int_16 FAR * FAR * png_int_16pp;
+typedef PNG_CONST char FAR * FAR * png_const_charpp;
+typedef char FAR * FAR * png_charpp;
+typedef png_fixed_point FAR * FAR * png_fixed_point_pp;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+typedef double FAR * FAR * png_doublepp;
+#endif
+
+/* Pointers to pointers to pointers; i.e., pointer to array */
+typedef char FAR * FAR * FAR * png_charppp;
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+/* SPC - Is this stuff deprecated? */
+/* It'll be removed as of libpng-1.3.0 - GR-P */
+/* libpng typedefs for types in zlib. If zlib changes
+ * or another compression library is used, then change these.
+ * Eliminates need to change all the source files.
+ */
+typedef charf * png_zcharp;
+typedef charf * FAR * png_zcharpp;
+typedef z_stream FAR * png_zstreamp;
+#endif /* (PNG_1_0_X) || defined(PNG_1_2_X) */
+
+/*
+ * Define PNG_BUILD_DLL if the module being built is a Windows
+ * LIBPNG DLL.
+ *
+ * Define PNG_USE_DLL if you want to *link* to the Windows LIBPNG DLL.
+ * It is equivalent to Microsoft predefined macro _DLL that is
+ * automatically defined when you compile using the share
+ * version of the CRT (C Run-Time library)
+ *
+ * The cygwin mods make this behavior a little different:
+ * Define PNG_BUILD_DLL if you are building a dll for use with cygwin
+ * Define PNG_STATIC if you are building a static library for use with cygwin,
+ * -or- if you are building an application that you want to link to the
+ * static library.
+ * PNG_USE_DLL is defined by default (no user action needed) unless one of
+ * the other flags is defined.
+ */
+
+#if !defined(PNG_DLL) && (defined(PNG_BUILD_DLL) || defined(PNG_USE_DLL))
+# define PNG_DLL
+#endif
+/* If CYGWIN, then disallow GLOBAL ARRAYS unless building a static lib.
+ * When building a static lib, default to no GLOBAL ARRAYS, but allow
+ * command-line override
+ */
+#if defined(__CYGWIN__)
+# if !defined(PNG_STATIC)
+# if defined(PNG_USE_GLOBAL_ARRAYS)
+# undef PNG_USE_GLOBAL_ARRAYS
+# endif
+# if !defined(PNG_USE_LOCAL_ARRAYS)
+# define PNG_USE_LOCAL_ARRAYS
+# endif
+# else
+# if defined(PNG_USE_LOCAL_ARRAYS) || defined(PNG_NO_GLOBAL_ARRAYS)
+# if defined(PNG_USE_GLOBAL_ARRAYS)
+# undef PNG_USE_GLOBAL_ARRAYS
+# endif
+# endif
+# endif
+# if !defined(PNG_USE_LOCAL_ARRAYS) && !defined(PNG_USE_GLOBAL_ARRAYS)
+# define PNG_USE_LOCAL_ARRAYS
+# endif
+#endif
+
+/* Do not use global arrays (helps with building DLL's)
+ * They are no longer used in libpng itself, since version 1.0.5c,
+ * but might be required for some pre-1.0.5c applications.
+ */
+#if !defined(PNG_USE_LOCAL_ARRAYS) && !defined(PNG_USE_GLOBAL_ARRAYS)
+# if defined(PNG_NO_GLOBAL_ARRAYS) || \
+ (defined(__GNUC__) && defined(PNG_DLL)) || defined(_MSC_VER)
+# define PNG_USE_LOCAL_ARRAYS
+# else
+# define PNG_USE_GLOBAL_ARRAYS
+# endif
+#endif
+
+#if defined(__CYGWIN__)
+# undef PNGAPI
+# define PNGAPI __cdecl
+# undef PNG_IMPEXP
+# define PNG_IMPEXP
+#endif
+
+/* If you define PNGAPI, e.g., with compiler option "-DPNGAPI=__stdcall",
+ * you may get warnings regarding the linkage of png_zalloc and png_zfree.
+ * Don't ignore those warnings; you must also reset the default calling
+ * convention in your compiler to match your PNGAPI, and you must build
+ * zlib and your applications the same way you build libpng.
+ */
+
+#if defined(__MINGW32__) && !defined(PNG_MODULEDEF)
+# ifndef PNG_NO_MODULEDEF
+# define PNG_NO_MODULEDEF
+# endif
+#endif
+
+#if !defined(PNG_IMPEXP) && defined(PNG_BUILD_DLL) && !defined(PNG_NO_MODULEDEF)
+# define PNG_IMPEXP
+#endif
+
+#if defined(PNG_DLL) || defined(_DLL) || defined(__DLL__ ) || \
+ (( defined(_Windows) || defined(_WINDOWS) || \
+ defined(WIN32) || defined(_WIN32) || defined(__WIN32__) ))
+
+# ifndef PNGAPI
+# if defined(__GNUC__) || (defined (_MSC_VER) && (_MSC_VER >= 800))
+# define PNGAPI __cdecl
+# else
+# define PNGAPI _cdecl
+# endif
+# endif
+
+# if !defined(PNG_IMPEXP) && (!defined(PNG_DLL) || \
+ 0 /* WINCOMPILER_WITH_NO_SUPPORT_FOR_DECLIMPEXP */)
+# define PNG_IMPEXP
+# endif
+
+# if !defined(PNG_IMPEXP)
+
+# define PNG_EXPORT_TYPE1(type,symbol) PNG_IMPEXP type PNGAPI symbol
+# define PNG_EXPORT_TYPE2(type,symbol) type PNG_IMPEXP PNGAPI symbol
+
+ /* Borland/Microsoft */
+# if defined(_MSC_VER) || defined(__BORLANDC__)
+# if (_MSC_VER >= 800) || (__BORLANDC__ >= 0x500)
+# define PNG_EXPORT PNG_EXPORT_TYPE1
+# else
+# define PNG_EXPORT PNG_EXPORT_TYPE2
+# if defined(PNG_BUILD_DLL)
+# define PNG_IMPEXP __export
+# else
+# define PNG_IMPEXP /*__import */ /* doesn't exist AFAIK in
+ VC++ */
+# endif /* Exists in Borland C++ for
+ C++ classes (== huge) */
+# endif
+# endif
+
+# if !defined(PNG_IMPEXP)
+# if defined(PNG_BUILD_DLL)
+# define PNG_IMPEXP __declspec(dllexport)
+# else
+# define PNG_IMPEXP __declspec(dllimport)
+# endif
+# endif
+# endif /* PNG_IMPEXP */
+#else /* !(DLL || non-cygwin WINDOWS) */
+# if (defined(__IBMC__) || defined(__IBMCPP__)) && defined(__OS2__)
+# ifndef PNGAPI
+# define PNGAPI _System
+# endif
+# else
+# if 0 /* ... other platforms, with other meanings */
+# endif
+# endif
+#endif
+
+#ifndef PNGAPI
+# define PNGAPI
+#endif
+#ifndef PNG_IMPEXP
+# define PNG_IMPEXP
+#endif
+
+#ifdef PNG_BUILDSYMS
+# ifndef PNG_EXPORT
+# define PNG_EXPORT(type,symbol) PNG_FUNCTION_EXPORT symbol END
+# endif
+# ifdef PNG_USE_GLOBAL_ARRAYS
+# ifndef PNG_EXPORT_VAR
+# define PNG_EXPORT_VAR(type) PNG_DATA_EXPORT
+# endif
+# endif
+#endif
+
+#ifndef PNG_EXPORT
+# define PNG_EXPORT(type,symbol) PNG_IMPEXP type PNGAPI symbol
+#endif
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+# ifndef PNG_EXPORT_VAR
+# define PNG_EXPORT_VAR(type) extern PNG_IMPEXP type
+# endif
+#endif
+
+/* User may want to use these so they are not in PNG_INTERNAL. Any library
+ * functions that are passed far data must be model independent.
+ */
+
+#ifndef PNG_ABORT
+# define PNG_ABORT() abort()
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+# define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#else
+# define png_jmpbuf(png_ptr) \
+ (LIBPNG_WAS_COMPILED_WITH__PNG_SETJMP_NOT_SUPPORTED)
+#endif
+
+#if defined(USE_FAR_KEYWORD) /* memory model independent fns */
+/* use this to make far-to-near assignments */
+# define CHECK 1
+# define NOCHECK 0
+# define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
+# define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
+# define png_snprintf _fsnprintf /* Added to v 1.2.19 */
+# define png_strcpy _fstrcpy
+# define png_strncpy _fstrncpy /* Added to v 1.2.6 */
+# define png_strlen _fstrlen
+# define png_memcmp _fmemcmp /* SJT: added */
+# define png_memcpy _fmemcpy
+# define png_memset _fmemset
+#else /* use the usual functions */
+# define CVT_PTR(ptr) (ptr)
+# define CVT_PTR_NOCHECK(ptr) (ptr)
+# ifndef PNG_NO_SNPRINTF
+# ifdef _MSC_VER
+# define png_snprintf _snprintf /* Added to v 1.2.19 */
+# define png_snprintf2 _snprintf
+# define png_snprintf6 _snprintf
+# else
+# define png_snprintf snprintf /* Added to v 1.2.19 */
+# define png_snprintf2 snprintf
+# define png_snprintf6 snprintf
+# endif
+# else
+ /* You don't have or don't want to use snprintf(). Caution: Using
+ * sprintf instead of snprintf exposes your application to accidental
+ * or malevolent buffer overflows. If you don't have snprintf()
+ * as a general rule you should provide one (you can get one from
+ * Portable OpenSSH). */
+# define png_snprintf(s1,n,fmt,x1) sprintf(s1,fmt,x1)
+# define png_snprintf2(s1,n,fmt,x1,x2) sprintf(s1,fmt,x1,x2)
+# define png_snprintf6(s1,n,fmt,x1,x2,x3,x4,x5,x6) \
+ sprintf(s1,fmt,x1,x2,x3,x4,x5,x6)
+# endif
+# define png_strcpy strcpy
+# define png_strncpy strncpy /* Added to v 1.2.6 */
+# define png_strlen strlen
+# define png_memcmp memcmp /* SJT: added */
+# define png_memcpy memcpy
+# define png_memset memset
+#endif
+/* End of memory model independent support */
+
+/* Just a little check that someone hasn't tried to define something
+ * contradictory.
+ */
+#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
+# undef PNG_ZBUF_SIZE
+# define PNG_ZBUF_SIZE 65536L
+#endif
+
+/* Added at libpng-1.2.8 */
+#endif /* PNG_VERSION_INFO_ONLY */
+
+#endif /* PNGCONF_H */
diff --git a/src/libpng/pngerror.c b/src/libpng/pngerror.c
new file mode 100644
index 0000000..bdafdc2
--- /dev/null
+++ b/src/libpng/pngerror.c
@@ -0,0 +1,341 @@
+
+/* pngerror.c - stub functions for i/o and memory allocation
+ *
+ * Last changed in libpng 1.2.22 [October 13, 2007]
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all error handling. Users who
+ * need special error handling are expected to write replacement functions
+ * and use png_set_error_fn() to use those functions. See the instructions
+ * at each function.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+static void /* PRIVATE */
+png_default_error PNGARG((png_structp png_ptr,
+ png_const_charp error_message));
+#ifndef PNG_NO_WARNINGS
+static void /* PRIVATE */
+png_default_warning PNGARG((png_structp png_ptr,
+ png_const_charp warning_message));
+#endif /* PNG_NO_WARNINGS */
+
+/* This function is called whenever there is a fatal error. This function
+ * should not be changed. If there is a need to handle errors differently,
+ * you should supply a replacement error function and use png_set_error_fn()
+ * to replace the error function at run-time.
+ */
+#ifndef PNG_NO_ERROR_TEXT
+void PNGAPI
+png_error(png_structp png_ptr, png_const_charp error_message)
+{
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ char msg[16];
+ if (png_ptr != NULL)
+ {
+ if (png_ptr->flags&
+ (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+ {
+ if (*error_message == '#')
+ {
+ int offset;
+ for (offset=1; offset<15; offset++)
+ if (*(error_message+offset) == ' ')
+ break;
+ if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+ {
+ int i;
+ for (i=0; i<offset-1; i++)
+ msg[i]=error_message[i+1];
+ msg[i]='\0';
+ error_message=msg;
+ }
+ else
+ error_message+=offset;
+ }
+ else
+ {
+ if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+ {
+ msg[0]='0';
+ msg[1]='\0';
+ error_message=msg;
+ }
+ }
+ }
+ }
+#endif
+ if (png_ptr != NULL && png_ptr->error_fn != NULL)
+ (*(png_ptr->error_fn))(png_ptr, error_message);
+
+ /* If the custom handler doesn't exist, or if it returns,
+ use the default handler, which will not return. */
+ png_default_error(png_ptr, error_message);
+}
+#else
+void PNGAPI
+png_err(png_structp png_ptr)
+{
+ if (png_ptr != NULL && png_ptr->error_fn != NULL)
+ (*(png_ptr->error_fn))(png_ptr, '\0');
+
+ /* If the custom handler doesn't exist, or if it returns,
+ use the default handler, which will not return. */
+ png_default_error(png_ptr, '\0');
+}
+#endif /* PNG_NO_ERROR_TEXT */
+
+#ifndef PNG_NO_WARNINGS
+/* This function is called whenever there is a non-fatal error. This function
+ * should not be changed. If there is a need to handle warnings differently,
+ * you should supply a replacement warning function and use
+ * png_set_error_fn() to replace the warning function at run-time.
+ */
+void PNGAPI
+png_warning(png_structp png_ptr, png_const_charp warning_message)
+{
+ int offset = 0;
+ if (png_ptr != NULL)
+ {
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ if (png_ptr->flags&
+ (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+#endif
+ {
+ if (*warning_message == '#')
+ {
+ for (offset=1; offset<15; offset++)
+ if (*(warning_message+offset) == ' ')
+ break;
+ }
+ }
+ if (png_ptr != NULL && png_ptr->warning_fn != NULL)
+ (*(png_ptr->warning_fn))(png_ptr, warning_message+offset);
+ }
+ else
+ png_default_warning(png_ptr, warning_message+offset);
+}
+#endif /* PNG_NO_WARNINGS */
+
+
+/* These utilities are used internally to build an error message that relates
+ * to the current chunk. The chunk name comes from png_ptr->chunk_name,
+ * this is used to prefix the message. The message is limited in length
+ * to 63 bytes, the name characters are output as hex digits wrapped in []
+ * if the character is invalid.
+ */
+#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
+static PNG_CONST char png_digit[16] = {
+ '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
+ 'A', 'B', 'C', 'D', 'E', 'F'
+};
+
+#if !defined(PNG_NO_WARNINGS) || !defined(PNG_NO_ERROR_TEXT)
+static void /* PRIVATE */
+png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp
+ error_message)
+{
+ int iout = 0, iin = 0;
+
+ while (iin < 4)
+ {
+ int c = png_ptr->chunk_name[iin++];
+ if (isnonalpha(c))
+ {
+ buffer[iout++] = '[';
+ buffer[iout++] = png_digit[(c & 0xf0) >> 4];
+ buffer[iout++] = png_digit[c & 0x0f];
+ buffer[iout++] = ']';
+ }
+ else
+ {
+ buffer[iout++] = (png_byte)c;
+ }
+ }
+
+ if (error_message == NULL)
+ buffer[iout] = '\0';
+ else
+ {
+ buffer[iout++] = ':';
+ buffer[iout++] = ' ';
+ png_strncpy(buffer+iout, error_message, 63);
+ buffer[iout+63] = '\0';
+ }
+}
+
+#ifdef PNG_READ_SUPPORTED
+void PNGAPI
+png_chunk_error(png_structp png_ptr, png_const_charp error_message)
+{
+ char msg[18+64];
+ if (png_ptr == NULL)
+ png_error(png_ptr, error_message);
+ else
+ {
+ png_format_buffer(png_ptr, msg, error_message);
+ png_error(png_ptr, msg);
+ }
+}
+#endif /* PNG_READ_SUPPORTED */
+#endif /* !defined(PNG_NO_WARNINGS) || !defined(PNG_NO_ERROR_TEXT) */
+
+#ifndef PNG_NO_WARNINGS
+void PNGAPI
+png_chunk_warning(png_structp png_ptr, png_const_charp warning_message)
+{
+ char msg[18+64];
+ if (png_ptr == NULL)
+ png_warning(png_ptr, warning_message);
+ else
+ {
+ png_format_buffer(png_ptr, msg, warning_message);
+ png_warning(png_ptr, msg);
+ }
+}
+#endif /* PNG_NO_WARNINGS */
+
+
+/* This is the default error handling function. Note that replacements for
+ * this function MUST NOT RETURN, or the program will likely crash. This
+ * function is used by default, or if the program supplies NULL for the
+ * error function pointer in png_set_error_fn().
+ */
+static void /* PRIVATE */
+png_default_error(png_structp png_ptr, png_const_charp error_message)
+{
+#ifndef PNG_NO_CONSOLE_IO
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ if (*error_message == '#')
+ {
+ int offset;
+ char error_number[16];
+ for (offset=0; offset<15; offset++)
+ {
+ error_number[offset] = *(error_message+offset+1);
+ if (*(error_message+offset) == ' ')
+ break;
+ }
+ if((offset > 1) && (offset < 15))
+ {
+ error_number[offset-1]='\0';
+ fprintf(stderr, "libpng error no. %s: %s\n", error_number,
+ error_message+offset);
+ }
+ else
+ fprintf(stderr, "libpng error: %s, offset=%d\n", error_message,offset);
+ }
+ else
+#endif
+ fprintf(stderr, "libpng error: %s\n", error_message);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+ if (png_ptr)
+ {
+# ifdef USE_FAR_KEYWORD
+ {
+ jmp_buf jmpbuf;
+ png_memcpy(jmpbuf, png_ptr->jmpbuf, png_sizeof(jmp_buf));
+ longjmp(jmpbuf, 1);
+ }
+# else
+ longjmp(png_ptr->jmpbuf, 1);
+# endif
+ }
+#else
+ PNG_ABORT();
+#endif
+#ifdef PNG_NO_CONSOLE_IO
+ error_message = error_message; /* make compiler happy */
+#endif
+}
+
+#ifndef PNG_NO_WARNINGS
+/* This function is called when there is a warning, but the library thinks
+ * it can continue anyway. Replacement functions don't have to do anything
+ * here if you don't want them to. In the default configuration, png_ptr is
+ * not used, but it is passed in case it may be useful.
+ */
+static void /* PRIVATE */
+png_default_warning(png_structp png_ptr, png_const_charp warning_message)
+{
+#ifndef PNG_NO_CONSOLE_IO
+# ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ if (*warning_message == '#')
+ {
+ int offset;
+ char warning_number[16];
+ for (offset=0; offset<15; offset++)
+ {
+ warning_number[offset]=*(warning_message+offset+1);
+ if (*(warning_message+offset) == ' ')
+ break;
+ }
+ if((offset > 1) && (offset < 15))
+ {
+ warning_number[offset-1]='\0';
+ fprintf(stderr, "libpng warning no. %s: %s\n", warning_number,
+ warning_message+offset);
+ }
+ else
+ fprintf(stderr, "libpng warning: %s\n", warning_message);
+ }
+ else
+# endif
+ fprintf(stderr, "libpng warning: %s\n", warning_message);
+#else
+ warning_message = warning_message; /* make compiler happy */
+#endif
+ png_ptr = png_ptr; /* make compiler happy */
+}
+#endif /* PNG_NO_WARNINGS */
+
+/* This function is called when the application wants to use another method
+ * of handling errors and warnings. Note that the error function MUST NOT
+ * return to the calling routine or serious problems will occur. The return
+ * method used in the default routine calls longjmp(png_ptr->jmpbuf, 1)
+ */
+void PNGAPI
+png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warning_fn)
+{
+ if (png_ptr == NULL)
+ return;
+ png_ptr->error_ptr = error_ptr;
+ png_ptr->error_fn = error_fn;
+ png_ptr->warning_fn = warning_fn;
+}
+
+
+/* This function returns a pointer to the error_ptr associated with the user
+ * functions. The application should free any memory associated with this
+ * pointer before png_write_destroy and png_read_destroy are called.
+ */
+png_voidp PNGAPI
+png_get_error_ptr(png_structp png_ptr)
+{
+ if (png_ptr == NULL)
+ return NULL;
+ return ((png_voidp)png_ptr->error_ptr);
+}
+
+
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+void PNGAPI
+png_set_strip_error_numbers(png_structp png_ptr, png_uint_32 strip_mode)
+{
+ if(png_ptr != NULL)
+ {
+ png_ptr->flags &=
+ ((~(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode);
+ }
+}
+#endif
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pnggccrd.c b/src/libpng/pnggccrd.c
new file mode 100644
index 0000000..a7248d6
--- /dev/null
+++ b/src/libpng/pnggccrd.c
@@ -0,0 +1,101 @@
+/* pnggccrd.c was removed from libpng-1.2.20. */
+
+/* This code snippet is for use by configure's compilation test. */
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && \
+ defined(PNG_MMX_CODE_SUPPORTED)
+int PNGAPI png_dummy_mmx_support(void);
+
+static int _mmx_supported = 2; // 0: no MMX; 1: MMX supported; 2: not tested
+
+int PNGAPI
+png_dummy_mmx_support(void) __attribute__((noinline));
+
+int PNGAPI
+png_dummy_mmx_support(void)
+{
+ int result;
+#if defined(PNG_MMX_CODE_SUPPORTED) // superfluous, but what the heck
+ __asm__ __volatile__ (
+#if defined(__x86_64__)
+ "pushq %%rbx \n\t" // rbx gets clobbered by CPUID instruction
+ "pushq %%rcx \n\t" // so does rcx...
+ "pushq %%rdx \n\t" // ...and rdx (but rcx & rdx safe on Linux)
+ "pushfq \n\t" // save Eflag to stack
+ "popq %%rax \n\t" // get Eflag from stack into rax
+ "movq %%rax, %%rcx \n\t" // make another copy of Eflag in rcx
+ "xorl $0x200000, %%eax \n\t" // toggle ID bit in Eflag (i.e., bit 21)
+ "pushq %%rax \n\t" // save modified Eflag back to stack
+ "popfq \n\t" // restore modified value to Eflag reg
+ "pushfq \n\t" // save Eflag to stack
+ "popq %%rax \n\t" // get Eflag from stack
+ "pushq %%rcx \n\t" // save original Eflag to stack
+ "popfq \n\t" // restore original Eflag
+#else
+ "pushl %%ebx \n\t" // ebx gets clobbered by CPUID instruction
+ "pushl %%ecx \n\t" // so does ecx...
+ "pushl %%edx \n\t" // ...and edx (but ecx & edx safe on Linux)
+ "pushfl \n\t" // save Eflag to stack
+ "popl %%eax \n\t" // get Eflag from stack into eax
+ "movl %%eax, %%ecx \n\t" // make another copy of Eflag in ecx
+ "xorl $0x200000, %%eax \n\t" // toggle ID bit in Eflag (i.e., bit 21)
+ "pushl %%eax \n\t" // save modified Eflag back to stack
+ "popfl \n\t" // restore modified value to Eflag reg
+ "pushfl \n\t" // save Eflag to stack
+ "popl %%eax \n\t" // get Eflag from stack
+ "pushl %%ecx \n\t" // save original Eflag to stack
+ "popfl \n\t" // restore original Eflag
+#endif
+ "xorl %%ecx, %%eax \n\t" // compare new Eflag with original Eflag
+ "jz 0f \n\t" // if same, CPUID instr. is not supported
+
+ "xorl %%eax, %%eax \n\t" // set eax to zero
+// ".byte 0x0f, 0xa2 \n\t" // CPUID instruction (two-byte opcode)
+ "cpuid \n\t" // get the CPU identification info
+ "cmpl $1, %%eax \n\t" // make sure eax return non-zero value
+ "jl 0f \n\t" // if eax is zero, MMX is not supported
+
+ "xorl %%eax, %%eax \n\t" // set eax to zero and...
+ "incl %%eax \n\t" // ...increment eax to 1. This pair is
+ // faster than the instruction "mov eax, 1"
+ "cpuid \n\t" // get the CPU identification info again
+ "andl $0x800000, %%edx \n\t" // mask out all bits but MMX bit (23)
+ "cmpl $0, %%edx \n\t" // 0 = MMX not supported
+ "jz 0f \n\t" // non-zero = yes, MMX IS supported
+
+ "movl $1, %%eax \n\t" // set return value to 1
+ "jmp 1f \n\t" // DONE: have MMX support
+
+ "0: \n\t" // .NOT_SUPPORTED: target label for jump instructions
+ "movl $0, %%eax \n\t" // set return value to 0
+ "1: \n\t" // .RETURN: target label for jump instructions
+#if defined(__x86_64__)
+ "popq %%rdx \n\t" // restore rdx
+ "popq %%rcx \n\t" // restore rcx
+ "popq %%rbx \n\t" // restore rbx
+#else
+ "popl %%edx \n\t" // restore edx
+ "popl %%ecx \n\t" // restore ecx
+ "popl %%ebx \n\t" // restore ebx
+#endif
+
+// "ret \n\t" // DONE: no MMX support
+ // (fall through to standard C "ret")
+
+ : "=a" (result) // output list
+
+ : // any variables used on input (none)
+
+ // no clobber list
+// , "%ebx", "%ecx", "%edx" // GRR: we handle these manually
+// , "memory" // if write to a variable gcc thought was in a reg
+// , "cc" // "condition codes" (flag bits)
+ );
+ _mmx_supported = result;
+#else
+ _mmx_supported = 0;
+#endif /* PNG_MMX_CODE_SUPPORTED */
+
+ return _mmx_supported;
+}
+#endif
diff --git a/src/libpng/pngget.c b/src/libpng/pngget.c
new file mode 100644
index 0000000..a0e90bb
--- /dev/null
+++ b/src/libpng/pngget.c
@@ -0,0 +1,901 @@
+
+/* pngget.c - retrieval of values from info struct
+ *
+ * Last changed in libpng 1.2.15 January 5, 2007
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+
+png_uint_32 PNGAPI
+png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ return(info_ptr->valid & flag);
+ else
+ return(0);
+}
+
+png_uint_32 PNGAPI
+png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ return(info_ptr->rowbytes);
+ else
+ return(0);
+}
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+png_bytepp PNGAPI
+png_get_rows(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ return(info_ptr->row_pointers);
+ else
+ return(0);
+}
+#endif
+
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* easy access to info, added in libpng-0.99 */
+png_uint_32 PNGAPI
+png_get_image_width(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ {
+ return info_ptr->width;
+ }
+ return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_image_height(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ {
+ return info_ptr->height;
+ }
+ return (0);
+}
+
+png_byte PNGAPI
+png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ {
+ return info_ptr->bit_depth;
+ }
+ return (0);
+}
+
+png_byte PNGAPI
+png_get_color_type(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ {
+ return info_ptr->color_type;
+ }
+ return (0);
+}
+
+png_byte PNGAPI
+png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ {
+ return info_ptr->filter_type;
+ }
+ return (0);
+}
+
+png_byte PNGAPI
+png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ {
+ return info_ptr->interlace_type;
+ }
+ return (0);
+}
+
+png_byte PNGAPI
+png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ {
+ return info_ptr->compression_type;
+ }
+ return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_pHYs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_x_pixels_per_meter");
+ if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+ return (0);
+ else return (info_ptr->x_pixels_per_unit);
+ }
+#else
+ return (0);
+#endif
+ return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_pHYs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_y_pixels_per_meter");
+ if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+ return (0);
+ else return (info_ptr->y_pixels_per_unit);
+ }
+#else
+ return (0);
+#endif
+ return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_pHYs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_pixels_per_meter");
+ if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER ||
+ info_ptr->x_pixels_per_unit != info_ptr->y_pixels_per_unit)
+ return (0);
+ else return (info_ptr->x_pixels_per_unit);
+ }
+#else
+ return (0);
+#endif
+ return (0);
+}
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+float PNGAPI
+png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
+ {
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_pHYs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_aspect_ratio");
+ if (info_ptr->x_pixels_per_unit == 0)
+ return ((float)0.0);
+ else
+ return ((float)((float)info_ptr->y_pixels_per_unit
+ /(float)info_ptr->x_pixels_per_unit));
+ }
+#else
+ return (0.0);
+#endif
+ return ((float)0.0);
+}
+#endif
+
+png_int_32 PNGAPI
+png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_oFFs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+ if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+ return (0);
+ else return (info_ptr->x_offset);
+ }
+#else
+ return (0);
+#endif
+ return (0);
+}
+
+png_int_32 PNGAPI
+png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_oFFs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+ if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+ return (0);
+ else return (info_ptr->y_offset);
+ }
+#else
+ return (0);
+#endif
+ return (0);
+}
+
+png_int_32 PNGAPI
+png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_oFFs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+ if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+ return (0);
+ else return (info_ptr->x_offset);
+ }
+#else
+ return (0);
+#endif
+ return (0);
+}
+
+png_int_32 PNGAPI
+png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_oFFs)
+ {
+ png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+ if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+ return (0);
+ else return (info_ptr->y_offset);
+ }
+#else
+ return (0);
+#endif
+ return (0);
+}
+
+#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+ return ((png_uint_32)((float)png_get_pixels_per_meter(png_ptr, info_ptr)
+ *.0254 +.5));
+}
+
+png_uint_32 PNGAPI
+png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+ return ((png_uint_32)((float)png_get_x_pixels_per_meter(png_ptr, info_ptr)
+ *.0254 +.5));
+}
+
+png_uint_32 PNGAPI
+png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+ return ((png_uint_32)((float)png_get_y_pixels_per_meter(png_ptr, info_ptr)
+ *.0254 +.5));
+}
+
+float PNGAPI
+png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+ return ((float)png_get_x_offset_microns(png_ptr, info_ptr)
+ *.00003937);
+}
+
+float PNGAPI
+png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+ return ((float)png_get_y_offset_microns(png_ptr, info_ptr)
+ *.00003937);
+}
+
+#if defined(PNG_pHYs_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+{
+ png_uint_32 retval = 0;
+
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+ {
+ png_debug1(1, "in %s retrieval function\n", "pHYs");
+ if (res_x != NULL)
+ {
+ *res_x = info_ptr->x_pixels_per_unit;
+ retval |= PNG_INFO_pHYs;
+ }
+ if (res_y != NULL)
+ {
+ *res_y = info_ptr->y_pixels_per_unit;
+ retval |= PNG_INFO_pHYs;
+ }
+ if (unit_type != NULL)
+ {
+ *unit_type = (int)info_ptr->phys_unit_type;
+ retval |= PNG_INFO_pHYs;
+ if(*unit_type == 1)
+ {
+ if (res_x != NULL) *res_x = (png_uint_32)(*res_x * .0254 + .50);
+ if (res_y != NULL) *res_y = (png_uint_32)(*res_y * .0254 + .50);
+ }
+ }
+ }
+ return (retval);
+}
+#endif /* PNG_pHYs_SUPPORTED */
+#endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
+
+/* png_get_channels really belongs in here, too, but it's been around longer */
+
+#endif /* PNG_EASY_ACCESS_SUPPORTED */
+
+png_byte PNGAPI
+png_get_channels(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ return(info_ptr->channels);
+ else
+ return (0);
+}
+
+png_bytep PNGAPI
+png_get_signature(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr != NULL && info_ptr != NULL)
+ return(info_ptr->signature);
+ else
+ return (NULL);
+}
+
+#if defined(PNG_bKGD_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
+ png_color_16p *background)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
+ && background != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "bKGD");
+ *background = &(info_ptr->background);
+ return (PNG_INFO_bKGD);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_cHRM(png_structp png_ptr, png_infop info_ptr,
+ double *white_x, double *white_y, double *red_x, double *red_y,
+ double *green_x, double *green_y, double *blue_x, double *blue_y)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
+ {
+ png_debug1(1, "in %s retrieval function\n", "cHRM");
+ if (white_x != NULL)
+ *white_x = (double)info_ptr->x_white;
+ if (white_y != NULL)
+ *white_y = (double)info_ptr->y_white;
+ if (red_x != NULL)
+ *red_x = (double)info_ptr->x_red;
+ if (red_y != NULL)
+ *red_y = (double)info_ptr->y_red;
+ if (green_x != NULL)
+ *green_x = (double)info_ptr->x_green;
+ if (green_y != NULL)
+ *green_y = (double)info_ptr->y_green;
+ if (blue_x != NULL)
+ *blue_x = (double)info_ptr->x_blue;
+ if (blue_y != NULL)
+ *blue_y = (double)info_ptr->y_blue;
+ return (PNG_INFO_cHRM);
+ }
+ return (0);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
+ png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x,
+ png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y,
+ png_fixed_point *blue_x, png_fixed_point *blue_y)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
+ {
+ png_debug1(1, "in %s retrieval function\n", "cHRM");
+ if (white_x != NULL)
+ *white_x = info_ptr->int_x_white;
+ if (white_y != NULL)
+ *white_y = info_ptr->int_y_white;
+ if (red_x != NULL)
+ *red_x = info_ptr->int_x_red;
+ if (red_y != NULL)
+ *red_y = info_ptr->int_y_red;
+ if (green_x != NULL)
+ *green_x = info_ptr->int_x_green;
+ if (green_y != NULL)
+ *green_y = info_ptr->int_y_green;
+ if (blue_x != NULL)
+ *blue_x = info_ptr->int_x_blue;
+ if (blue_y != NULL)
+ *blue_y = info_ptr->int_y_blue;
+ return (PNG_INFO_cHRM);
+ }
+ return (0);
+}
+#endif
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+ && file_gamma != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "gAMA");
+ *file_gamma = (double)info_ptr->gamma;
+ return (PNG_INFO_gAMA);
+ }
+ return (0);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_gAMA_fixed(png_structp png_ptr, png_infop info_ptr,
+ png_fixed_point *int_file_gamma)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+ && int_file_gamma != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "gAMA");
+ *int_file_gamma = info_ptr->int_gamma;
+ return (PNG_INFO_gAMA);
+ }
+ return (0);
+}
+#endif
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
+ && file_srgb_intent != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "sRGB");
+ *file_srgb_intent = (int)info_ptr->srgb_intent;
+ return (PNG_INFO_sRGB);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_iCCP(png_structp png_ptr, png_infop info_ptr,
+ png_charpp name, int *compression_type,
+ png_charpp profile, png_uint_32 *proflen)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
+ && name != NULL && profile != NULL && proflen != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "iCCP");
+ *name = info_ptr->iccp_name;
+ *profile = info_ptr->iccp_profile;
+ /* compression_type is a dummy so the API won't have to change
+ if we introduce multiple compression types later. */
+ *proflen = (int)info_ptr->iccp_proflen;
+ *compression_type = (int)info_ptr->iccp_compression;
+ return (PNG_INFO_iCCP);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_sPLT(png_structp png_ptr, png_infop info_ptr,
+ png_sPLT_tpp spalettes)
+{
+ if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
+ {
+ *spalettes = info_ptr->splt_palettes;
+ return ((png_uint_32)info_ptr->splt_palettes_num);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
+ && hist != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "hIST");
+ *hist = info_ptr->hist;
+ return (PNG_INFO_hIST);
+ }
+ return (0);
+}
+#endif
+
+png_uint_32 PNGAPI
+png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 *width, png_uint_32 *height, int *bit_depth,
+ int *color_type, int *interlace_type, int *compression_type,
+ int *filter_type)
+
+{
+ if (png_ptr != NULL && info_ptr != NULL && width != NULL && height != NULL &&
+ bit_depth != NULL && color_type != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "IHDR");
+ *width = info_ptr->width;
+ *height = info_ptr->height;
+ *bit_depth = info_ptr->bit_depth;
+ if (info_ptr->bit_depth < 1 || info_ptr->bit_depth > 16)
+ png_error(png_ptr, "Invalid bit depth");
+ *color_type = info_ptr->color_type;
+ if (info_ptr->color_type > 6)
+ png_error(png_ptr, "Invalid color type");
+ if (compression_type != NULL)
+ *compression_type = info_ptr->compression_type;
+ if (filter_type != NULL)
+ *filter_type = info_ptr->filter_type;
+ if (interlace_type != NULL)
+ *interlace_type = info_ptr->interlace_type;
+
+ /* check for potential overflow of rowbytes */
+ if (*width == 0 || *width > PNG_UINT_31_MAX)
+ png_error(png_ptr, "Invalid image width");
+ if (*height == 0 || *height > PNG_UINT_31_MAX)
+ png_error(png_ptr, "Invalid image height");
+ if (info_ptr->width > (PNG_UINT_32_MAX
+ >> 3) /* 8-byte RGBA pixels */
+ - 64 /* bigrowbuf hack */
+ - 1 /* filter byte */
+ - 7*8 /* rounding of width to multiple of 8 pixels */
+ - 8) /* extra max_pixel_depth pad */
+ {
+ png_warning(png_ptr,
+ "Width too large for libpng to process image data.");
+ }
+ return (1);
+ }
+ return (0);
+}
+
+#if defined(PNG_oFFs_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
+ png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
+ && offset_x != NULL && offset_y != NULL && unit_type != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "oFFs");
+ *offset_x = info_ptr->x_offset;
+ *offset_y = info_ptr->y_offset;
+ *unit_type = (int)info_ptr->offset_unit_type;
+ return (PNG_INFO_oFFs);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
+ png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
+ png_charp *units, png_charpp *params)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)
+ && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
+ nparams != NULL && units != NULL && params != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "pCAL");
+ *purpose = info_ptr->pcal_purpose;
+ *X0 = info_ptr->pcal_X0;
+ *X1 = info_ptr->pcal_X1;
+ *type = (int)info_ptr->pcal_type;
+ *nparams = (int)info_ptr->pcal_nparams;
+ *units = info_ptr->pcal_units;
+ *params = info_ptr->pcal_params;
+ return (PNG_INFO_pCAL);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_sCAL(png_structp png_ptr, png_infop info_ptr,
+ int *unit, double *width, double *height)
+{
+ if (png_ptr != NULL && info_ptr != NULL &&
+ (info_ptr->valid & PNG_INFO_sCAL))
+ {
+ *unit = info_ptr->scal_unit;
+ *width = info_ptr->scal_pixel_width;
+ *height = info_ptr->scal_pixel_height;
+ return (PNG_INFO_sCAL);
+ }
+ return(0);
+}
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_sCAL_s(png_structp png_ptr, png_infop info_ptr,
+ int *unit, png_charpp width, png_charpp height)
+{
+ if (png_ptr != NULL && info_ptr != NULL &&
+ (info_ptr->valid & PNG_INFO_sCAL))
+ {
+ *unit = info_ptr->scal_unit;
+ *width = info_ptr->scal_s_width;
+ *height = info_ptr->scal_s_height;
+ return (PNG_INFO_sCAL);
+ }
+ return(0);
+}
+#endif
+#endif
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+{
+ png_uint_32 retval = 0;
+
+ if (png_ptr != NULL && info_ptr != NULL &&
+ (info_ptr->valid & PNG_INFO_pHYs))
+ {
+ png_debug1(1, "in %s retrieval function\n", "pHYs");
+ if (res_x != NULL)
+ {
+ *res_x = info_ptr->x_pixels_per_unit;
+ retval |= PNG_INFO_pHYs;
+ }
+ if (res_y != NULL)
+ {
+ *res_y = info_ptr->y_pixels_per_unit;
+ retval |= PNG_INFO_pHYs;
+ }
+ if (unit_type != NULL)
+ {
+ *unit_type = (int)info_ptr->phys_unit_type;
+ retval |= PNG_INFO_pHYs;
+ }
+ }
+ return (retval);
+}
+#endif
+
+png_uint_32 PNGAPI
+png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
+ int *num_palette)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE)
+ && palette != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "PLTE");
+ *palette = info_ptr->palette;
+ *num_palette = info_ptr->num_palette;
+ png_debug1(3, "num_palette = %d\n", *num_palette);
+ return (PNG_INFO_PLTE);
+ }
+ return (0);
+}
+
+#if defined(PNG_sBIT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
+ && sig_bit != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "sBIT");
+ *sig_bit = &(info_ptr->sig_bit);
+ return (PNG_INFO_sBIT);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
+ int *num_text)
+{
+ if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
+ {
+ png_debug1(1, "in %s retrieval function\n",
+ (png_ptr->chunk_name[0] == '\0' ? "text"
+ : (png_const_charp)png_ptr->chunk_name));
+ if (text_ptr != NULL)
+ *text_ptr = info_ptr->text;
+ if (num_text != NULL)
+ *num_text = info_ptr->num_text;
+ return ((png_uint_32)info_ptr->num_text);
+ }
+ if (num_text != NULL)
+ *num_text = 0;
+ return(0);
+}
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
+{
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)
+ && mod_time != NULL)
+ {
+ png_debug1(1, "in %s retrieval function\n", "tIME");
+ *mod_time = &(info_ptr->mod_time);
+ return (PNG_INFO_tIME);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
+ png_bytep *trans, int *num_trans, png_color_16p *trans_values)
+{
+ png_uint_32 retval = 0;
+ if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+ {
+ png_debug1(1, "in %s retrieval function\n", "tRNS");
+ if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (trans != NULL)
+ {
+ *trans = info_ptr->trans;
+ retval |= PNG_INFO_tRNS;
+ }
+ if (trans_values != NULL)
+ *trans_values = &(info_ptr->trans_values);
+ }
+ else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
+ {
+ if (trans_values != NULL)
+ {
+ *trans_values = &(info_ptr->trans_values);
+ retval |= PNG_INFO_tRNS;
+ }
+ if(trans != NULL)
+ *trans = NULL;
+ }
+ if(num_trans != NULL)
+ {
+ *num_trans = info_ptr->num_trans;
+ retval |= PNG_INFO_tRNS;
+ }
+ }
+ return (retval);
+}
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_unknown_chunks(png_structp png_ptr, png_infop info_ptr,
+ png_unknown_chunkpp unknowns)
+{
+ if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL)
+ {
+ *unknowns = info_ptr->unknown_chunks;
+ return ((png_uint_32)info_ptr->unknown_chunks_num);
+ }
+ return (0);
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+png_byte PNGAPI
+png_get_rgb_to_gray_status (png_structp png_ptr)
+{
+ return (png_byte)(png_ptr? png_ptr->rgb_to_gray_status : 0);
+}
+#endif
+
+#if defined(PNG_USER_CHUNKS_SUPPORTED)
+png_voidp PNGAPI
+png_get_user_chunk_ptr(png_structp png_ptr)
+{
+ return (png_ptr? png_ptr->user_chunk_ptr : NULL);
+}
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+png_uint_32 PNGAPI
+png_get_compression_buffer_size(png_structp png_ptr)
+{
+ return (png_uint_32)(png_ptr? png_ptr->zbuf_size : 0L);
+}
+#endif
+
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+#ifndef PNG_1_0_X
+/* this function was added to libpng 1.2.0 and should exist by default */
+png_uint_32 PNGAPI
+png_get_asm_flags (png_structp png_ptr)
+{
+ /* obsolete, to be removed from libpng-1.4.0 */
+ return (png_ptr? 0L: 0L);
+}
+
+/* this function was added to libpng 1.2.0 and should exist by default */
+png_uint_32 PNGAPI
+png_get_asm_flagmask (int flag_select)
+{
+ /* obsolete, to be removed from libpng-1.4.0 */
+ flag_select=flag_select;
+ return 0L;
+}
+
+ /* GRR: could add this: && defined(PNG_MMX_CODE_SUPPORTED) */
+/* this function was added to libpng 1.2.0 */
+png_uint_32 PNGAPI
+png_get_mmx_flagmask (int flag_select, int *compilerID)
+{
+ /* obsolete, to be removed from libpng-1.4.0 */
+ flag_select=flag_select;
+ *compilerID = -1; /* unknown (i.e., no asm/MMX code compiled) */
+ return 0L;
+}
+
+/* this function was added to libpng 1.2.0 */
+png_byte PNGAPI
+png_get_mmx_bitdepth_threshold (png_structp png_ptr)
+{
+ /* obsolete, to be removed from libpng-1.4.0 */
+ return (png_ptr? 0: 0);
+}
+
+/* this function was added to libpng 1.2.0 */
+png_uint_32 PNGAPI
+png_get_mmx_rowbytes_threshold (png_structp png_ptr)
+{
+ /* obsolete, to be removed from libpng-1.4.0 */
+ return (png_ptr? 0L: 0L);
+}
+#endif /* ?PNG_1_0_X */
+#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* these functions were added to libpng 1.2.6 */
+png_uint_32 PNGAPI
+png_get_user_width_max (png_structp png_ptr)
+{
+ return (png_ptr? png_ptr->user_width_max : 0);
+}
+png_uint_32 PNGAPI
+png_get_user_height_max (png_structp png_ptr)
+{
+ return (png_ptr? png_ptr->user_height_max : 0);
+}
+#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+
+
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngmem.c b/src/libpng/pngmem.c
new file mode 100644
index 0000000..248060f
--- /dev/null
+++ b/src/libpng/pngmem.c
@@ -0,0 +1,608 @@
+
+/* pngmem.c - stub functions for memory allocation
+ *
+ * Last changed in libpng 1.2.13 November 13, 2006
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2006 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all memory allocation. Users who
+ * need special memory handling are expected to supply replacement
+ * functions for png_malloc() and png_free(), and to use
+ * png_create_read_struct_2() and png_create_write_struct_2() to
+ * identify the replacement functions.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+
+/* Borland DOS special memory handler */
+#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
+/* if you change this, be sure to change the one in png.h also */
+
+/* Allocate memory for a png_struct. The malloc and memset can be replaced
+ by a single call to calloc() if this is thought to improve performance. */
+png_voidp /* PRIVATE */
+png_create_struct(int type)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+ return (png_create_struct_2(type, png_malloc_ptr_NULL, png_voidp_NULL));
+}
+
+/* Alternate version of png_create_struct, for use with user-defined malloc. */
+png_voidp /* PRIVATE */
+png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+ png_size_t size;
+ png_voidp struct_ptr;
+
+ if (type == PNG_STRUCT_INFO)
+ size = png_sizeof(png_info);
+ else if (type == PNG_STRUCT_PNG)
+ size = png_sizeof(png_struct);
+ else
+ return (png_get_copyright(NULL));
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(malloc_fn != NULL)
+ {
+ png_struct dummy_struct;
+ png_structp png_ptr = &dummy_struct;
+ png_ptr->mem_ptr=mem_ptr;
+ struct_ptr = (*(malloc_fn))(png_ptr, (png_uint_32)size);
+ }
+ else
+#endif /* PNG_USER_MEM_SUPPORTED */
+ struct_ptr = (png_voidp)farmalloc(size);
+ if (struct_ptr != NULL)
+ png_memset(struct_ptr, 0, size);
+ return (struct_ptr);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct(png_voidp struct_ptr)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2(struct_ptr, png_free_ptr_NULL, png_voidp_NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
+ png_voidp mem_ptr)
+{
+#endif
+ if (struct_ptr != NULL)
+ {
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(free_fn != NULL)
+ {
+ png_struct dummy_struct;
+ png_structp png_ptr = &dummy_struct;
+ png_ptr->mem_ptr=mem_ptr;
+ (*(free_fn))(png_ptr, struct_ptr);
+ return;
+ }
+#endif /* PNG_USER_MEM_SUPPORTED */
+ farfree (struct_ptr);
+ }
+}
+
+/* Allocate memory. For reasonable files, size should never exceed
+ * 64K. However, zlib may allocate more then 64K if you don't tell
+ * it not to. See zconf.h and png.h for more information. zlib does
+ * need to allocate exactly 64K, so whatever you call here must
+ * have the ability to do that.
+ *
+ * Borland seems to have a problem in DOS mode for exactly 64K.
+ * It gives you a segment with an offset of 8 (perhaps to store its
+ * memory stuff). zlib doesn't like this at all, so we have to
+ * detect and deal with it. This code should not be needed in
+ * Windows or OS/2 modes, and only in 16 bit mode. This code has
+ * been updated by Alexander Lehmann for version 0.89 to waste less
+ * memory.
+ *
+ * Note that we can't use png_size_t for the "size" declaration,
+ * since on some systems a png_size_t is a 16-bit quantity, and as a
+ * result, we would be truncating potentially larger memory requests
+ * (which should cause a fatal error) and introducing major problems.
+ */
+
+png_voidp PNGAPI
+png_malloc(png_structp png_ptr, png_uint_32 size)
+{
+ png_voidp ret;
+
+ if (png_ptr == NULL || size == 0)
+ return (NULL);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(png_ptr->malloc_fn != NULL)
+ ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));
+ else
+ ret = (png_malloc_default(png_ptr, size));
+ if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Out of memory!");
+ return (ret);
+}
+
+png_voidp PNGAPI
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
+{
+ png_voidp ret;
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+ if (png_ptr == NULL || size == 0)
+ return (NULL);
+
+#ifdef PNG_MAX_MALLOC_64K
+ if (size > (png_uint_32)65536L)
+ {
+ png_warning(png_ptr, "Cannot Allocate > 64K");
+ ret = NULL;
+ }
+ else
+#endif
+
+ if (size != (size_t)size)
+ ret = NULL;
+ else if (size == (png_uint_32)65536L)
+ {
+ if (png_ptr->offset_table == NULL)
+ {
+ /* try to see if we need to do any of this fancy stuff */
+ ret = farmalloc(size);
+ if (ret == NULL || ((png_size_t)ret & 0xffff))
+ {
+ int num_blocks;
+ png_uint_32 total_size;
+ png_bytep table;
+ int i;
+ png_byte huge * hptr;
+
+ if (ret != NULL)
+ {
+ farfree(ret);
+ ret = NULL;
+ }
+
+ if(png_ptr->zlib_window_bits > 14)
+ num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
+ else
+ num_blocks = 1;
+ if (png_ptr->zlib_mem_level >= 7)
+ num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));
+ else
+ num_blocks++;
+
+ total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16;
+
+ table = farmalloc(total_size);
+
+ if (table == NULL)
+ {
+#ifndef PNG_USER_MEM_SUPPORTED
+ if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Out Of Memory."); /* Note "O" and "M" */
+ else
+ png_warning(png_ptr, "Out Of Memory.");
+#endif
+ return (NULL);
+ }
+
+ if ((png_size_t)table & 0xfff0)
+ {
+#ifndef PNG_USER_MEM_SUPPORTED
+ if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr,
+ "Farmalloc didn't return normalized pointer");
+ else
+ png_warning(png_ptr,
+ "Farmalloc didn't return normalized pointer");
+#endif
+ return (NULL);
+ }
+
+ png_ptr->offset_table = table;
+ png_ptr->offset_table_ptr = farmalloc(num_blocks *
+ png_sizeof (png_bytep));
+
+ if (png_ptr->offset_table_ptr == NULL)
+ {
+#ifndef PNG_USER_MEM_SUPPORTED
+ if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Out Of memory."); /* Note "O" and "M" */
+ else
+ png_warning(png_ptr, "Out Of memory.");
+#endif
+ return (NULL);
+ }
+
+ hptr = (png_byte huge *)table;
+ if ((png_size_t)hptr & 0xf)
+ {
+ hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+ hptr = hptr + 16L; /* "hptr += 16L" fails on Turbo C++ 3.0 */
+ }
+ for (i = 0; i < num_blocks; i++)
+ {
+ png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+ hptr = hptr + (png_uint_32)65536L; /* "+=" fails on TC++3.0 */
+ }
+
+ png_ptr->offset_table_number = num_blocks;
+ png_ptr->offset_table_count = 0;
+ png_ptr->offset_table_count_free = 0;
+ }
+ }
+
+ if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
+ {
+#ifndef PNG_USER_MEM_SUPPORTED
+ if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Out of Memory."); /* Note "o" and "M" */
+ else
+ png_warning(png_ptr, "Out of Memory.");
+#endif
+ return (NULL);
+ }
+
+ ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
+ }
+ else
+ ret = farmalloc(size);
+
+#ifndef PNG_USER_MEM_SUPPORTED
+ if (ret == NULL)
+ {
+ if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Out of memory."); /* Note "o" and "m" */
+ else
+ png_warning(png_ptr, "Out of memory."); /* Note "o" and "m" */
+ }
+#endif
+
+ return (ret);
+}
+
+/* free a pointer allocated by png_malloc(). In the default
+ configuration, png_ptr is not used, but is passed in case it
+ is needed. If ptr is NULL, return without taking any action. */
+void PNGAPI
+png_free(png_structp png_ptr, png_voidp ptr)
+{
+ if (png_ptr == NULL || ptr == NULL)
+ return;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ if (png_ptr->free_fn != NULL)
+ {
+ (*(png_ptr->free_fn))(png_ptr, ptr);
+ return;
+ }
+ else png_free_default(png_ptr, ptr);
+}
+
+void PNGAPI
+png_free_default(png_structp png_ptr, png_voidp ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+ if(png_ptr == NULL) return;
+
+ if (png_ptr->offset_table != NULL)
+ {
+ int i;
+
+ for (i = 0; i < png_ptr->offset_table_count; i++)
+ {
+ if (ptr == png_ptr->offset_table_ptr[i])
+ {
+ ptr = NULL;
+ png_ptr->offset_table_count_free++;
+ break;
+ }
+ }
+ if (png_ptr->offset_table_count_free == png_ptr->offset_table_count)
+ {
+ farfree(png_ptr->offset_table);
+ farfree(png_ptr->offset_table_ptr);
+ png_ptr->offset_table = NULL;
+ png_ptr->offset_table_ptr = NULL;
+ }
+ }
+
+ if (ptr != NULL)
+ {
+ farfree(ptr);
+ }
+}
+
+#else /* Not the Borland DOS special memory handler */
+
+/* Allocate memory for a png_struct or a png_info. The malloc and
+ memset can be replaced by a single call to calloc() if this is thought
+ to improve performance noticably. */
+png_voidp /* PRIVATE */
+png_create_struct(int type)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+ return (png_create_struct_2(type, png_malloc_ptr_NULL, png_voidp_NULL));
+}
+
+/* Allocate memory for a png_struct or a png_info. The malloc and
+ memset can be replaced by a single call to calloc() if this is thought
+ to improve performance noticably. */
+png_voidp /* PRIVATE */
+png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+ png_size_t size;
+ png_voidp struct_ptr;
+
+ if (type == PNG_STRUCT_INFO)
+ size = png_sizeof(png_info);
+ else if (type == PNG_STRUCT_PNG)
+ size = png_sizeof(png_struct);
+ else
+ return (NULL);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(malloc_fn != NULL)
+ {
+ png_struct dummy_struct;
+ png_structp png_ptr = &dummy_struct;
+ png_ptr->mem_ptr=mem_ptr;
+ struct_ptr = (*(malloc_fn))(png_ptr, size);
+ if (struct_ptr != NULL)
+ png_memset(struct_ptr, 0, size);
+ return (struct_ptr);
+ }
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+#if defined(__TURBOC__) && !defined(__FLAT__)
+ struct_ptr = (png_voidp)farmalloc(size);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+ struct_ptr = (png_voidp)halloc(size,1);
+# else
+ struct_ptr = (png_voidp)malloc(size);
+# endif
+#endif
+ if (struct_ptr != NULL)
+ png_memset(struct_ptr, 0, size);
+
+ return (struct_ptr);
+}
+
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct(png_voidp struct_ptr)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2(struct_ptr, png_free_ptr_NULL, png_voidp_NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
+ png_voidp mem_ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+ if (struct_ptr != NULL)
+ {
+#ifdef PNG_USER_MEM_SUPPORTED
+ if(free_fn != NULL)
+ {
+ png_struct dummy_struct;
+ png_structp png_ptr = &dummy_struct;
+ png_ptr->mem_ptr=mem_ptr;
+ (*(free_fn))(png_ptr, struct_ptr);
+ return;
+ }
+#endif /* PNG_USER_MEM_SUPPORTED */
+#if defined(__TURBOC__) && !defined(__FLAT__)
+ farfree(struct_ptr);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+ hfree(struct_ptr);
+# else
+ free(struct_ptr);
+# endif
+#endif
+ }
+}
+
+/* Allocate memory. For reasonable files, size should never exceed
+ 64K. However, zlib may allocate more then 64K if you don't tell
+ it not to. See zconf.h and png.h for more information. zlib does
+ need to allocate exactly 64K, so whatever you call here must
+ have the ability to do that. */
+
+png_voidp PNGAPI
+png_malloc(png_structp png_ptr, png_uint_32 size)
+{
+ png_voidp ret;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ if (png_ptr == NULL || size == 0)
+ return (NULL);
+
+ if(png_ptr->malloc_fn != NULL)
+ ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));
+ else
+ ret = (png_malloc_default(png_ptr, size));
+ if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Out of Memory!");
+ return (ret);
+}
+
+png_voidp PNGAPI
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
+{
+ png_voidp ret;
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+ if (png_ptr == NULL || size == 0)
+ return (NULL);
+
+#ifdef PNG_MAX_MALLOC_64K
+ if (size > (png_uint_32)65536L)
+ {
+#ifndef PNG_USER_MEM_SUPPORTED
+ if(png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Cannot Allocate > 64K");
+ else
+#endif
+ return NULL;
+ }
+#endif
+
+ /* Check for overflow */
+#if defined(__TURBOC__) && !defined(__FLAT__)
+ if (size != (unsigned long)size)
+ ret = NULL;
+ else
+ ret = farmalloc(size);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+ if (size != (unsigned long)size)
+ ret = NULL;
+ else
+ ret = halloc(size, 1);
+# else
+ if (size != (size_t)size)
+ ret = NULL;
+ else
+ ret = malloc((size_t)size);
+# endif
+#endif
+
+#ifndef PNG_USER_MEM_SUPPORTED
+ if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+ png_error(png_ptr, "Out of Memory");
+#endif
+
+ return (ret);
+}
+
+/* Free a pointer allocated by png_malloc(). If ptr is NULL, return
+ without taking any action. */
+void PNGAPI
+png_free(png_structp png_ptr, png_voidp ptr)
+{
+ if (png_ptr == NULL || ptr == NULL)
+ return;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ if (png_ptr->free_fn != NULL)
+ {
+ (*(png_ptr->free_fn))(png_ptr, ptr);
+ return;
+ }
+ else png_free_default(png_ptr, ptr);
+}
+void PNGAPI
+png_free_default(png_structp png_ptr, png_voidp ptr)
+{
+ if (png_ptr == NULL || ptr == NULL)
+ return;
+
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+#if defined(__TURBOC__) && !defined(__FLAT__)
+ farfree(ptr);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+ hfree(ptr);
+# else
+ free(ptr);
+# endif
+#endif
+}
+
+#endif /* Not Borland DOS special memory handler */
+
+#if defined(PNG_1_0_X)
+# define png_malloc_warn png_malloc
+#else
+/* This function was added at libpng version 1.2.3. The png_malloc_warn()
+ * function will set up png_malloc() to issue a png_warning and return NULL
+ * instead of issuing a png_error, if it fails to allocate the requested
+ * memory.
+ */
+png_voidp PNGAPI
+png_malloc_warn(png_structp png_ptr, png_uint_32 size)
+{
+ png_voidp ptr;
+ png_uint_32 save_flags;
+ if(png_ptr == NULL) return (NULL);
+
+ save_flags=png_ptr->flags;
+ png_ptr->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
+ ptr = (png_voidp)png_malloc((png_structp)png_ptr, size);
+ png_ptr->flags=save_flags;
+ return(ptr);
+}
+#endif
+
+png_voidp PNGAPI
+png_memcpy_check (png_structp png_ptr, png_voidp s1, png_voidp s2,
+ png_uint_32 length)
+{
+ png_size_t size;
+
+ size = (png_size_t)length;
+ if ((png_uint_32)size != length)
+ png_error(png_ptr,"Overflow in png_memcpy_check.");
+
+ return(png_memcpy (s1, s2, size));
+}
+
+png_voidp PNGAPI
+png_memset_check (png_structp png_ptr, png_voidp s1, int value,
+ png_uint_32 length)
+{
+ png_size_t size;
+
+ size = (png_size_t)length;
+ if ((png_uint_32)size != length)
+ png_error(png_ptr,"Overflow in png_memset_check.");
+
+ return (png_memset (s1, value, size));
+
+}
+
+#ifdef PNG_USER_MEM_SUPPORTED
+/* This function is called when the application wants to use another method
+ * of allocating and freeing memory.
+ */
+void PNGAPI
+png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr
+ malloc_fn, png_free_ptr free_fn)
+{
+ if(png_ptr != NULL) {
+ png_ptr->mem_ptr = mem_ptr;
+ png_ptr->malloc_fn = malloc_fn;
+ png_ptr->free_fn = free_fn;
+ }
+}
+
+/* This function returns a pointer to the mem_ptr associated with the user
+ * functions. The application should free any memory associated with this
+ * pointer before png_write_destroy and png_read_destroy are called.
+ */
+png_voidp PNGAPI
+png_get_mem_ptr(png_structp png_ptr)
+{
+ if(png_ptr == NULL) return (NULL);
+ return ((png_voidp)png_ptr->mem_ptr);
+}
+#endif /* PNG_USER_MEM_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngpread.c b/src/libpng/pngpread.c
new file mode 100644
index 0000000..cb6f6d3
--- /dev/null
+++ b/src/libpng/pngpread.c
@@ -0,0 +1,1584 @@
+
+/* pngpread.c - read a png file in push mode
+ *
+ * Last changed in libpng 1.2.22 [October 13, 2007]
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+
+/* push model modes */
+#define PNG_READ_SIG_MODE 0
+#define PNG_READ_CHUNK_MODE 1
+#define PNG_READ_IDAT_MODE 2
+#define PNG_SKIP_MODE 3
+#define PNG_READ_tEXt_MODE 4
+#define PNG_READ_zTXt_MODE 5
+#define PNG_READ_DONE_MODE 6
+#define PNG_READ_iTXt_MODE 7
+#define PNG_ERROR_MODE 8
+
+void PNGAPI
+png_process_data(png_structp png_ptr, png_infop info_ptr,
+ png_bytep buffer, png_size_t buffer_size)
+{
+ if(png_ptr == NULL) return;
+ png_push_restore_buffer(png_ptr, buffer, buffer_size);
+
+ while (png_ptr->buffer_size)
+ {
+ png_process_some_data(png_ptr, info_ptr);
+ }
+}
+
+/* What we do with the incoming data depends on what we were previously
+ * doing before we ran out of data...
+ */
+void /* PRIVATE */
+png_process_some_data(png_structp png_ptr, png_infop info_ptr)
+{
+ if(png_ptr == NULL) return;
+ switch (png_ptr->process_mode)
+ {
+ case PNG_READ_SIG_MODE:
+ {
+ png_push_read_sig(png_ptr, info_ptr);
+ break;
+ }
+ case PNG_READ_CHUNK_MODE:
+ {
+ png_push_read_chunk(png_ptr, info_ptr);
+ break;
+ }
+ case PNG_READ_IDAT_MODE:
+ {
+ png_push_read_IDAT(png_ptr);
+ break;
+ }
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ case PNG_READ_tEXt_MODE:
+ {
+ png_push_read_tEXt(png_ptr, info_ptr);
+ break;
+ }
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ case PNG_READ_zTXt_MODE:
+ {
+ png_push_read_zTXt(png_ptr, info_ptr);
+ break;
+ }
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ case PNG_READ_iTXt_MODE:
+ {
+ png_push_read_iTXt(png_ptr, info_ptr);
+ break;
+ }
+#endif
+ case PNG_SKIP_MODE:
+ {
+ png_push_crc_finish(png_ptr);
+ break;
+ }
+ default:
+ {
+ png_ptr->buffer_size = 0;
+ break;
+ }
+ }
+}
+
+/* Read any remaining signature bytes from the stream and compare them with
+ * the correct PNG signature. It is possible that this routine is called
+ * with bytes already read from the signature, either because they have been
+ * checked by the calling application, or because of multiple calls to this
+ * routine.
+ */
+void /* PRIVATE */
+png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
+{
+ png_size_t num_checked = png_ptr->sig_bytes,
+ num_to_check = 8 - num_checked;
+
+ if (png_ptr->buffer_size < num_to_check)
+ {
+ num_to_check = png_ptr->buffer_size;
+ }
+
+ png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
+ num_to_check);
+ png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes+num_to_check);
+
+ if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
+ {
+ if (num_checked < 4 &&
+ png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+ png_error(png_ptr, "Not a PNG file");
+ else
+ png_error(png_ptr, "PNG file corrupted by ASCII conversion");
+ }
+ else
+ {
+ if (png_ptr->sig_bytes >= 8)
+ {
+ png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+ }
+ }
+}
+
+void /* PRIVATE */
+png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IHDR;
+ PNG_CONST PNG_IDAT;
+ PNG_CONST PNG_IEND;
+ PNG_CONST PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+ PNG_CONST PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+ PNG_CONST PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+ PNG_CONST PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+ PNG_CONST PNG_hIST;
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ PNG_CONST PNG_iCCP;
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ PNG_CONST PNG_iTXt;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+ PNG_CONST PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+ PNG_CONST PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+ PNG_CONST PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+ PNG_CONST PNG_sBIT;
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+ PNG_CONST PNG_sCAL;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ PNG_CONST PNG_sRGB;
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ PNG_CONST PNG_sPLT;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ PNG_CONST PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+ PNG_CONST PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ PNG_CONST PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ PNG_CONST PNG_zTXt;
+#endif
+#endif /* PNG_USE_LOCAL_ARRAYS */
+ /* First we make sure we have enough data for the 4 byte chunk name
+ * and the 4 byte chunk length before proceeding with decoding the
+ * chunk data. To fully decode each of these chunks, we also make
+ * sure we have enough data in the buffer for the 4 byte CRC at the
+ * end of every chunk (except IDAT, which is handled separately).
+ */
+ if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+ {
+ png_byte chunk_length[4];
+
+ if (png_ptr->buffer_size < 8)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_fill_buffer(png_ptr, chunk_length, 4);
+ png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+ png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
+ }
+
+ if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ if(png_ptr->mode & PNG_AFTER_IDAT)
+ png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
+
+ if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
+ }
+ else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
+
+ png_ptr->process_mode = PNG_READ_DONE_MODE;
+ png_push_have_end(png_ptr, info_ptr);
+ }
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ png_ptr->mode |= PNG_HAVE_IDAT;
+ png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
+ if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ png_ptr->mode |= PNG_HAVE_PLTE;
+ else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before IDAT");
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+ !(png_ptr->mode & PNG_HAVE_PLTE))
+ png_error(png_ptr, "Missing PLTE before IDAT");
+ }
+ }
+#endif
+ else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
+ }
+ else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ /* If we reach an IDAT chunk, this means we have read all of the
+ * header chunks, and we can start reading the image (or if this
+ * is called after the image has been read - we have an error).
+ */
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before IDAT");
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+ !(png_ptr->mode & PNG_HAVE_PLTE))
+ png_error(png_ptr, "Missing PLTE before IDAT");
+
+ if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
+ if (png_ptr->push_length == 0)
+ return;
+
+ if (png_ptr->mode & PNG_AFTER_IDAT)
+ png_error(png_ptr, "Too many IDAT's found");
+ }
+
+ png_ptr->idat_size = png_ptr->push_length;
+ png_ptr->mode |= PNG_HAVE_IDAT;
+ png_ptr->process_mode = PNG_READ_IDAT_MODE;
+ png_push_have_info(png_ptr, info_ptr);
+ png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+ png_ptr->zstream.next_out = png_ptr->row_buf;
+ return;
+ }
+#if defined(PNG_READ_gAMA_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_bKGD_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+ else
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+ png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
+ }
+
+ png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
+}
+
+void /* PRIVATE */
+png_push_crc_skip(png_structp png_ptr, png_uint_32 skip)
+{
+ png_ptr->process_mode = PNG_SKIP_MODE;
+ png_ptr->skip_length = skip;
+}
+
+void /* PRIVATE */
+png_push_crc_finish(png_structp png_ptr)
+{
+ if (png_ptr->skip_length && png_ptr->save_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->skip_length < (png_uint_32)png_ptr->save_buffer_size)
+ save_size = (png_size_t)png_ptr->skip_length;
+ else
+ save_size = png_ptr->save_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
+
+ png_ptr->skip_length -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->save_buffer_size -= save_size;
+ png_ptr->save_buffer_ptr += save_size;
+ }
+ if (png_ptr->skip_length && png_ptr->current_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->skip_length < (png_uint_32)png_ptr->current_buffer_size)
+ save_size = (png_size_t)png_ptr->skip_length;
+ else
+ save_size = png_ptr->current_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
+
+ png_ptr->skip_length -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->current_buffer_size -= save_size;
+ png_ptr->current_buffer_ptr += save_size;
+ }
+ if (!png_ptr->skip_length)
+ {
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_crc_finish(png_ptr, 0);
+ png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+ }
+}
+
+void PNGAPI
+png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
+{
+ png_bytep ptr;
+
+ if(png_ptr == NULL) return;
+ ptr = buffer;
+ if (png_ptr->save_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (length < png_ptr->save_buffer_size)
+ save_size = length;
+ else
+ save_size = png_ptr->save_buffer_size;
+
+ png_memcpy(ptr, png_ptr->save_buffer_ptr, save_size);
+ length -= save_size;
+ ptr += save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->save_buffer_size -= save_size;
+ png_ptr->save_buffer_ptr += save_size;
+ }
+ if (length && png_ptr->current_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (length < png_ptr->current_buffer_size)
+ save_size = length;
+ else
+ save_size = png_ptr->current_buffer_size;
+
+ png_memcpy(ptr, png_ptr->current_buffer_ptr, save_size);
+ png_ptr->buffer_size -= save_size;
+ png_ptr->current_buffer_size -= save_size;
+ png_ptr->current_buffer_ptr += save_size;
+ }
+}
+
+void /* PRIVATE */
+png_push_save_buffer(png_structp png_ptr)
+{
+ if (png_ptr->save_buffer_size)
+ {
+ if (png_ptr->save_buffer_ptr != png_ptr->save_buffer)
+ {
+ png_size_t i,istop;
+ png_bytep sp;
+ png_bytep dp;
+
+ istop = png_ptr->save_buffer_size;
+ for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer;
+ i < istop; i++, sp++, dp++)
+ {
+ *dp = *sp;
+ }
+ }
+ }
+ if (png_ptr->save_buffer_size + png_ptr->current_buffer_size >
+ png_ptr->save_buffer_max)
+ {
+ png_size_t new_max;
+ png_bytep old_buffer;
+
+ if (png_ptr->save_buffer_size > PNG_SIZE_MAX -
+ (png_ptr->current_buffer_size + 256))
+ {
+ png_error(png_ptr, "Potential overflow of save_buffer");
+ }
+ new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256;
+ old_buffer = png_ptr->save_buffer;
+ png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)new_max);
+ png_memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
+ png_free(png_ptr, old_buffer);
+ png_ptr->save_buffer_max = new_max;
+ }
+ if (png_ptr->current_buffer_size)
+ {
+ png_memcpy(png_ptr->save_buffer + png_ptr->save_buffer_size,
+ png_ptr->current_buffer_ptr, png_ptr->current_buffer_size);
+ png_ptr->save_buffer_size += png_ptr->current_buffer_size;
+ png_ptr->current_buffer_size = 0;
+ }
+ png_ptr->save_buffer_ptr = png_ptr->save_buffer;
+ png_ptr->buffer_size = 0;
+}
+
+void /* PRIVATE */
+png_push_restore_buffer(png_structp png_ptr, png_bytep buffer,
+ png_size_t buffer_length)
+{
+ png_ptr->current_buffer = buffer;
+ png_ptr->current_buffer_size = buffer_length;
+ png_ptr->buffer_size = buffer_length + png_ptr->save_buffer_size;
+ png_ptr->current_buffer_ptr = png_ptr->current_buffer;
+}
+
+void /* PRIVATE */
+png_push_read_IDAT(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IDAT;
+#endif
+ if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+ {
+ png_byte chunk_length[4];
+
+ if (png_ptr->buffer_size < 8)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_fill_buffer(png_ptr, chunk_length, 4);
+ png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+ png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
+
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+ png_error(png_ptr, "Not enough compressed data");
+ return;
+ }
+
+ png_ptr->idat_size = png_ptr->push_length;
+ }
+ if (png_ptr->idat_size && png_ptr->save_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->idat_size < (png_uint_32)png_ptr->save_buffer_size)
+ {
+ save_size = (png_size_t)png_ptr->idat_size;
+ /* check for overflow */
+ if((png_uint_32)save_size != png_ptr->idat_size)
+ png_error(png_ptr, "save_size overflowed in pngpread");
+ }
+ else
+ save_size = png_ptr->save_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+ png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
+ png_ptr->idat_size -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->save_buffer_size -= save_size;
+ png_ptr->save_buffer_ptr += save_size;
+ }
+ if (png_ptr->idat_size && png_ptr->current_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->idat_size < (png_uint_32)png_ptr->current_buffer_size)
+ {
+ save_size = (png_size_t)png_ptr->idat_size;
+ /* check for overflow */
+ if((png_uint_32)save_size != png_ptr->idat_size)
+ png_error(png_ptr, "save_size overflowed in pngpread");
+ }
+ else
+ save_size = png_ptr->current_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+ png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
+
+ png_ptr->idat_size -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->current_buffer_size -= save_size;
+ png_ptr->current_buffer_ptr += save_size;
+ }
+ if (!png_ptr->idat_size)
+ {
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_crc_finish(png_ptr, 0);
+ png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
+ png_ptr->mode |= PNG_AFTER_IDAT;
+ }
+}
+
+void /* PRIVATE */
+png_process_IDAT_data(png_structp png_ptr, png_bytep buffer,
+ png_size_t buffer_length)
+{
+ int ret;
+
+ if ((png_ptr->flags & PNG_FLAG_ZLIB_FINISHED) && buffer_length)
+ png_error(png_ptr, "Extra compression data");
+
+ png_ptr->zstream.next_in = buffer;
+ png_ptr->zstream.avail_in = (uInt)buffer_length;
+ for(;;)
+ {
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+ if (ret != Z_OK)
+ {
+ if (ret == Z_STREAM_END)
+ {
+ if (png_ptr->zstream.avail_in)
+ png_error(png_ptr, "Extra compressed data");
+ if (!(png_ptr->zstream.avail_out))
+ {
+ png_push_process_row(png_ptr);
+ }
+
+ png_ptr->mode |= PNG_AFTER_IDAT;
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+ break;
+ }
+ else if (ret == Z_BUF_ERROR)
+ break;
+ else
+ png_error(png_ptr, "Decompression Error");
+ }
+ if (!(png_ptr->zstream.avail_out))
+ {
+ if ((
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+ png_ptr->interlaced && png_ptr->pass > 6) ||
+ (!png_ptr->interlaced &&
+#endif
+ png_ptr->row_number == png_ptr->num_rows))
+ {
+ if (png_ptr->zstream.avail_in)
+ png_warning(png_ptr, "Too much data in IDAT chunks");
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+ break;
+ }
+ png_push_process_row(png_ptr);
+ png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+ png_ptr->zstream.next_out = png_ptr->row_buf;
+ }
+ else
+ break;
+ }
+}
+
+void /* PRIVATE */
+png_push_process_row(png_structp png_ptr)
+{
+ png_ptr->row_info.color_type = png_ptr->color_type;
+ png_ptr->row_info.width = png_ptr->iwidth;
+ png_ptr->row_info.channels = png_ptr->channels;
+ png_ptr->row_info.bit_depth = png_ptr->bit_depth;
+ png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
+
+ png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+ png_ptr->row_info.width);
+
+ png_read_filter_row(png_ptr, &(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->prev_row + 1,
+ (int)(png_ptr->row_buf[0]));
+
+ png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+ png_ptr->rowbytes + 1);
+
+ if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+ png_do_read_transformations(png_ptr);
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+ /* blow up interlaced rows to full size */
+ if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+ {
+ if (png_ptr->pass < 6)
+/* old interface (pre-1.0.9):
+ png_do_read_interlace(&(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
+ */
+ png_do_read_interlace(png_ptr);
+
+ switch (png_ptr->pass)
+ {
+ case 0:
+ {
+ int i;
+ for (i = 0; i < 8 && png_ptr->pass == 0; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr); /* updates png_ptr->pass */
+ }
+ if (png_ptr->pass == 2) /* pass 1 might be empty */
+ {
+ for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ if (png_ptr->pass == 4 && png_ptr->height <= 4)
+ {
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ if (png_ptr->pass == 6 && png_ptr->height <= 4)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ break;
+ }
+ case 1:
+ {
+ int i;
+ for (i = 0; i < 8 && png_ptr->pass == 1; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 2) /* skip top 4 generated rows */
+ {
+ for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ break;
+ }
+ case 2:
+ {
+ int i;
+ for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 4) /* pass 3 might be empty */
+ {
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ break;
+ }
+ case 3:
+ {
+ int i;
+ for (i = 0; i < 4 && png_ptr->pass == 3; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 4) /* skip top two generated rows */
+ {
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ break;
+ }
+ case 4:
+ {
+ int i;
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 6) /* pass 5 might be empty */
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ break;
+ }
+ case 5:
+ {
+ int i;
+ for (i = 0; i < 2 && png_ptr->pass == 5; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 6) /* skip top generated row */
+ {
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ break;
+ }
+ case 6:
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ if (png_ptr->pass != 6)
+ break;
+ png_push_have_row(png_ptr, png_bytep_NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ }
+ else
+#endif
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+}
+
+void /* PRIVATE */
+png_read_push_finish_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+ /* start of interlace block */
+ PNG_CONST int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
+
+ /* offset to next interlace block */
+ PNG_CONST int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
+
+ /* start of interlace block in the y direction */
+ PNG_CONST int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
+
+ /* offset to next interlace block in the y direction */
+ PNG_CONST int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
+
+ /* Height of interlace block. This is not currently used - if you need
+ * it, uncomment it here and in png.h
+ PNG_CONST int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
+ */
+#endif
+
+ png_ptr->row_number++;
+ if (png_ptr->row_number < png_ptr->num_rows)
+ return;
+
+ if (png_ptr->interlaced)
+ {
+ png_ptr->row_number = 0;
+ png_memset_check(png_ptr, png_ptr->prev_row, 0,
+ png_ptr->rowbytes + 1);
+ do
+ {
+ png_ptr->pass++;
+ if ((png_ptr->pass == 1 && png_ptr->width < 5) ||
+ (png_ptr->pass == 3 && png_ptr->width < 3) ||
+ (png_ptr->pass == 5 && png_ptr->width < 2))
+ png_ptr->pass++;
+
+ if (png_ptr->pass > 7)
+ png_ptr->pass--;
+ if (png_ptr->pass >= 7)
+ break;
+
+ png_ptr->iwidth = (png_ptr->width +
+ png_pass_inc[png_ptr->pass] - 1 -
+ png_pass_start[png_ptr->pass]) /
+ png_pass_inc[png_ptr->pass];
+
+ png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,
+ png_ptr->iwidth) + 1;
+
+ if (png_ptr->transformations & PNG_INTERLACE)
+ break;
+
+ png_ptr->num_rows = (png_ptr->height +
+ png_pass_yinc[png_ptr->pass] - 1 -
+ png_pass_ystart[png_ptr->pass]) /
+ png_pass_yinc[png_ptr->pass];
+
+ } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0);
+ }
+}
+
+#if defined(PNG_READ_tEXt_SUPPORTED)
+void /* PRIVATE */
+png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
+{
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
+ {
+ png_error(png_ptr, "Out of place tEXt");
+ info_ptr = info_ptr; /* to quiet some compiler warnings */
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ png_ptr->skip_length = 0; /* This may not be necessary */
+
+ if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
+ {
+ png_warning(png_ptr, "tEXt chunk too large to fit in memory");
+ png_ptr->skip_length = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+
+ png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)(length+1));
+ png_ptr->current_text[length] = '\0';
+ png_ptr->current_text_ptr = png_ptr->current_text;
+ png_ptr->current_text_size = (png_size_t)length;
+ png_ptr->current_text_left = (png_size_t)length;
+ png_ptr->process_mode = PNG_READ_tEXt_MODE;
+}
+
+void /* PRIVATE */
+png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->buffer_size && png_ptr->current_text_left)
+ {
+ png_size_t text_size;
+
+ if (png_ptr->buffer_size < png_ptr->current_text_left)
+ text_size = png_ptr->buffer_size;
+ else
+ text_size = png_ptr->current_text_left;
+ png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+ png_ptr->current_text_left -= text_size;
+ png_ptr->current_text_ptr += text_size;
+ }
+ if (!(png_ptr->current_text_left))
+ {
+ png_textp text_ptr;
+ png_charp text;
+ png_charp key;
+ int ret;
+
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_crc_finish(png_ptr);
+
+#if defined(PNG_MAX_MALLOC_64K)
+ if (png_ptr->skip_length)
+ return;
+#endif
+
+ key = png_ptr->current_text;
+
+ for (text = key; *text; text++)
+ /* empty loop */ ;
+
+ if (text < key + png_ptr->current_text_size)
+ text++;
+
+ text_ptr = (png_textp)png_malloc(png_ptr,
+ (png_uint_32)png_sizeof(png_text));
+ text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
+ text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+ text_ptr->lang = NULL;
+ text_ptr->lang_key = NULL;
+#endif
+ text_ptr->text = text;
+
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, key);
+ png_free(png_ptr, text_ptr);
+ png_ptr->current_text = NULL;
+
+ if (ret)
+ png_warning(png_ptr, "Insufficient memory to store text chunk.");
+ }
+}
+#endif
+
+#if defined(PNG_READ_zTXt_SUPPORTED)
+void /* PRIVATE */
+png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
+{
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
+ {
+ png_error(png_ptr, "Out of place zTXt");
+ info_ptr = info_ptr; /* to quiet some compiler warnings */
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ /* We can't handle zTXt chunks > 64K, since we don't have enough space
+ * to be able to store the uncompressed data. Actually, the threshold
+ * is probably around 32K, but it isn't as definite as 64K is.
+ */
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "zTXt chunk too large to fit in memory");
+ png_push_crc_skip(png_ptr, length);
+ return;
+ }
+#endif
+
+ png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)(length+1));
+ png_ptr->current_text[length] = '\0';
+ png_ptr->current_text_ptr = png_ptr->current_text;
+ png_ptr->current_text_size = (png_size_t)length;
+ png_ptr->current_text_left = (png_size_t)length;
+ png_ptr->process_mode = PNG_READ_zTXt_MODE;
+}
+
+void /* PRIVATE */
+png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->buffer_size && png_ptr->current_text_left)
+ {
+ png_size_t text_size;
+
+ if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left)
+ text_size = png_ptr->buffer_size;
+ else
+ text_size = png_ptr->current_text_left;
+ png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+ png_ptr->current_text_left -= text_size;
+ png_ptr->current_text_ptr += text_size;
+ }
+ if (!(png_ptr->current_text_left))
+ {
+ png_textp text_ptr;
+ png_charp text;
+ png_charp key;
+ int ret;
+ png_size_t text_size, key_size;
+
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_crc_finish(png_ptr);
+
+ key = png_ptr->current_text;
+
+ for (text = key; *text; text++)
+ /* empty loop */ ;
+
+ /* zTXt can't have zero text */
+ if (text >= key + png_ptr->current_text_size)
+ {
+ png_ptr->current_text = NULL;
+ png_free(png_ptr, key);
+ return;
+ }
+
+ text++;
+
+ if (*text != PNG_TEXT_COMPRESSION_zTXt) /* check compression byte */
+ {
+ png_ptr->current_text = NULL;
+ png_free(png_ptr, key);
+ return;
+ }
+
+ text++;
+
+ png_ptr->zstream.next_in = (png_bytep )text;
+ png_ptr->zstream.avail_in = (uInt)(png_ptr->current_text_size -
+ (text - key));
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+ key_size = text - key;
+ text_size = 0;
+ text = NULL;
+ ret = Z_STREAM_END;
+
+ while (png_ptr->zstream.avail_in)
+ {
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+ if (ret != Z_OK && ret != Z_STREAM_END)
+ {
+ inflateReset(&png_ptr->zstream);
+ png_ptr->zstream.avail_in = 0;
+ png_ptr->current_text = NULL;
+ png_free(png_ptr, key);
+ png_free(png_ptr, text);
+ return;
+ }
+ if (!(png_ptr->zstream.avail_out) || ret == Z_STREAM_END)
+ {
+ if (text == NULL)
+ {
+ text = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
+ + key_size + 1));
+ png_memcpy(text + key_size, png_ptr->zbuf,
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+ png_memcpy(text, key, key_size);
+ text_size = key_size + png_ptr->zbuf_size -
+ png_ptr->zstream.avail_out;
+ *(text + text_size) = '\0';
+ }
+ else
+ {
+ png_charp tmp;
+
+ tmp = text;
+ text = (png_charp)png_malloc(png_ptr, text_size +
+ (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
+ + 1));
+ png_memcpy(text, tmp, text_size);
+ png_free(png_ptr, tmp);
+ png_memcpy(text + text_size, png_ptr->zbuf,
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+ text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+ *(text + text_size) = '\0';
+ }
+ if (ret != Z_STREAM_END)
+ {
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ }
+ }
+ else
+ {
+ break;
+ }
+
+ if (ret == Z_STREAM_END)
+ break;
+ }
+
+ inflateReset(&png_ptr->zstream);
+ png_ptr->zstream.avail_in = 0;
+
+ if (ret != Z_STREAM_END)
+ {
+ png_ptr->current_text = NULL;
+ png_free(png_ptr, key);
+ png_free(png_ptr, text);
+ return;
+ }
+
+ png_ptr->current_text = NULL;
+ png_free(png_ptr, key);
+ key = text;
+ text += key_size;
+
+ text_ptr = (png_textp)png_malloc(png_ptr,
+ (png_uint_32)png_sizeof(png_text));
+ text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
+ text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+ text_ptr->lang = NULL;
+ text_ptr->lang_key = NULL;
+#endif
+ text_ptr->text = text;
+
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, key);
+ png_free(png_ptr, text_ptr);
+
+ if (ret)
+ png_warning(png_ptr, "Insufficient memory to store text chunk.");
+ }
+}
+#endif
+
+#if defined(PNG_READ_iTXt_SUPPORTED)
+void /* PRIVATE */
+png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
+{
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
+ {
+ png_error(png_ptr, "Out of place iTXt");
+ info_ptr = info_ptr; /* to quiet some compiler warnings */
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ png_ptr->skip_length = 0; /* This may not be necessary */
+
+ if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
+ {
+ png_warning(png_ptr, "iTXt chunk too large to fit in memory");
+ png_ptr->skip_length = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+
+ png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)(length+1));
+ png_ptr->current_text[length] = '\0';
+ png_ptr->current_text_ptr = png_ptr->current_text;
+ png_ptr->current_text_size = (png_size_t)length;
+ png_ptr->current_text_left = (png_size_t)length;
+ png_ptr->process_mode = PNG_READ_iTXt_MODE;
+}
+
+void /* PRIVATE */
+png_push_read_iTXt(png_structp png_ptr, png_infop info_ptr)
+{
+
+ if (png_ptr->buffer_size && png_ptr->current_text_left)
+ {
+ png_size_t text_size;
+
+ if (png_ptr->buffer_size < png_ptr->current_text_left)
+ text_size = png_ptr->buffer_size;
+ else
+ text_size = png_ptr->current_text_left;
+ png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+ png_ptr->current_text_left -= text_size;
+ png_ptr->current_text_ptr += text_size;
+ }
+ if (!(png_ptr->current_text_left))
+ {
+ png_textp text_ptr;
+ png_charp key;
+ int comp_flag;
+ png_charp lang;
+ png_charp lang_key;
+ png_charp text;
+ int ret;
+
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_crc_finish(png_ptr);
+
+#if defined(PNG_MAX_MALLOC_64K)
+ if (png_ptr->skip_length)
+ return;
+#endif
+
+ key = png_ptr->current_text;
+
+ for (lang = key; *lang; lang++)
+ /* empty loop */ ;
+
+ if (lang < key + png_ptr->current_text_size - 3)
+ lang++;
+
+ comp_flag = *lang++;
+ lang++; /* skip comp_type, always zero */
+
+ for (lang_key = lang; *lang_key; lang_key++)
+ /* empty loop */ ;
+ lang_key++; /* skip NUL separator */
+
+ text=lang_key;
+ if (lang_key < key + png_ptr->current_text_size - 1)
+ {
+ for (; *text; text++)
+ /* empty loop */ ;
+ }
+
+ if (text < key + png_ptr->current_text_size)
+ text++;
+
+ text_ptr = (png_textp)png_malloc(png_ptr,
+ (png_uint_32)png_sizeof(png_text));
+ text_ptr->compression = comp_flag + 2;
+ text_ptr->key = key;
+ text_ptr->lang = lang;
+ text_ptr->lang_key = lang_key;
+ text_ptr->text = text;
+ text_ptr->text_length = 0;
+ text_ptr->itxt_length = png_strlen(text);
+
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+ png_ptr->current_text = NULL;
+
+ png_free(png_ptr, text_ptr);
+ if (ret)
+ png_warning(png_ptr, "Insufficient memory to store iTXt chunk.");
+ }
+}
+#endif
+
+/* This function is called when we haven't found a handler for this
+ * chunk. If there isn't a problem with the chunk itself (ie a bad chunk
+ * name or a critical chunk), the chunk is (currently) silently ignored.
+ */
+void /* PRIVATE */
+png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
+{
+ png_uint_32 skip=0;
+ png_check_chunk_name(png_ptr, png_ptr->chunk_name);
+
+ if (!(png_ptr->chunk_name[0] & 0x20))
+ {
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+ if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+ PNG_HANDLE_CHUNK_ALWAYS
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+ && png_ptr->read_user_chunk_fn == NULL
+#endif
+ )
+#endif
+ png_chunk_error(png_ptr, "unknown critical chunk");
+
+ info_ptr = info_ptr; /* to quiet some compiler warnings */
+ }
+
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+ if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
+ {
+#ifdef PNG_MAX_MALLOC_64K
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "unknown chunk too large to fit in memory");
+ skip = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+ png_strncpy((png_charp)png_ptr->unknown_chunk.name,
+ (png_charp)png_ptr->chunk_name, 4);
+ png_ptr->unknown_chunk.name[4] = '\0';
+ png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
+ png_ptr->unknown_chunk.size = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+ if(png_ptr->read_user_chunk_fn != NULL)
+ {
+ /* callback to user unknown chunk handler */
+ int ret;
+ ret = (*(png_ptr->read_user_chunk_fn))
+ (png_ptr, &png_ptr->unknown_chunk);
+ if (ret < 0)
+ png_chunk_error(png_ptr, "error in user chunk");
+ if (ret == 0)
+ {
+ if (!(png_ptr->chunk_name[0] & 0x20))
+ if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+ PNG_HANDLE_CHUNK_ALWAYS)
+ png_chunk_error(png_ptr, "unknown critical chunk");
+ png_set_unknown_chunks(png_ptr, info_ptr,
+ &png_ptr->unknown_chunk, 1);
+ }
+ }
+#else
+ png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
+#endif
+ png_free(png_ptr, png_ptr->unknown_chunk.data);
+ png_ptr->unknown_chunk.data = NULL;
+ }
+ else
+#endif
+ skip=length;
+ png_push_crc_skip(png_ptr, skip);
+}
+
+void /* PRIVATE */
+png_push_have_info(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->info_fn != NULL)
+ (*(png_ptr->info_fn))(png_ptr, info_ptr);
+}
+
+void /* PRIVATE */
+png_push_have_end(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->end_fn != NULL)
+ (*(png_ptr->end_fn))(png_ptr, info_ptr);
+}
+
+void /* PRIVATE */
+png_push_have_row(png_structp png_ptr, png_bytep row)
+{
+ if (png_ptr->row_fn != NULL)
+ (*(png_ptr->row_fn))(png_ptr, row, png_ptr->row_number,
+ (int)png_ptr->pass);
+}
+
+void PNGAPI
+png_progressive_combine_row (png_structp png_ptr,
+ png_bytep old_row, png_bytep new_row)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST int FARDATA png_pass_dsp_mask[7] =
+ {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+#endif
+ if(png_ptr == NULL) return;
+ if (new_row != NULL) /* new_row must == png_ptr->row_buf here. */
+ png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]);
+}
+
+void PNGAPI
+png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr,
+ png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
+ png_progressive_end_ptr end_fn)
+{
+ if(png_ptr == NULL) return;
+ png_ptr->info_fn = info_fn;
+ png_ptr->row_fn = row_fn;
+ png_ptr->end_fn = end_fn;
+
+ png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer);
+}
+
+png_voidp PNGAPI
+png_get_progressive_ptr(png_structp png_ptr)
+{
+ if(png_ptr == NULL) return (NULL);
+ return png_ptr->io_ptr;
+}
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
diff --git a/src/libpng/pngread.c b/src/libpng/pngread.c
new file mode 100644
index 0000000..02efb0d
--- /dev/null
+++ b/src/libpng/pngread.c
@@ -0,0 +1,1472 @@
+
+/* pngread.c - read a PNG file
+ *
+ * Last changed in libpng 1.2.20 September 7, 2007
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file contains routines that an application calls directly to
+ * read a PNG file or stream.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED)
+
+/* Create a PNG structure for reading, and allocate any memory needed. */
+png_structp PNGAPI
+png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn)
+{
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn,
+ warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
+}
+
+/* Alternate create PNG structure for reading, and allocate any memory needed. */
+png_structp PNGAPI
+png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+ png_malloc_ptr malloc_fn, png_free_ptr free_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+ png_structp png_ptr;
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+ jmp_buf jmpbuf;
+#endif
+#endif
+
+ int i;
+
+ png_debug(1, "in png_create_read_struct\n");
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
+ (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
+#else
+ png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+#endif
+ if (png_ptr == NULL)
+ return (NULL);
+
+ /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+ png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+ if (setjmp(jmpbuf))
+#else
+ if (setjmp(png_ptr->jmpbuf))
+#endif
+ {
+ png_free(png_ptr, png_ptr->zbuf);
+ png_ptr->zbuf=NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2((png_voidp)png_ptr,
+ (png_free_ptr)free_fn, (png_voidp)mem_ptr);
+#else
+ png_destroy_struct((png_voidp)png_ptr);
+#endif
+ return (NULL);
+ }
+#ifdef USE_FAR_KEYWORD
+ png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#endif
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
+#endif
+
+ png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
+
+ i=0;
+ do
+ {
+ if(user_png_ver[i] != png_libpng_ver[i])
+ png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+ } while (png_libpng_ver[i++]);
+
+ if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
+ {
+ /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
+ * we must recompile any applications that use any older library version.
+ * For versions after libpng 1.0, we will be compatible, so we need
+ * only check the first digit.
+ */
+ if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
+ (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
+ (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char msg[80];
+ if (user_png_ver)
+ {
+ png_snprintf(msg, 80,
+ "Application was compiled with png.h from libpng-%.20s",
+ user_png_ver);
+ png_warning(png_ptr, msg);
+ }
+ png_snprintf(msg, 80,
+ "Application is running with png.c from libpng-%.20s",
+ png_libpng_ver);
+ png_warning(png_ptr, msg);
+#endif
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "Incompatible libpng version in application and library");
+ }
+ }
+
+ /* initialize zbuf - compression buffer */
+ png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+ png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)png_ptr->zbuf_size);
+ png_ptr->zstream.zalloc = png_zalloc;
+ png_ptr->zstream.zfree = png_zfree;
+ png_ptr->zstream.opaque = (voidpf)png_ptr;
+
+ switch (inflateInit(&png_ptr->zstream))
+ {
+ case Z_OK: /* Do nothing */ break;
+ case Z_MEM_ERROR:
+ case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
+ case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
+ default: png_error(png_ptr, "Unknown zlib error");
+ }
+
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+ png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
+
+#ifdef PNG_SETJMP_SUPPORTED
+/* Applications that neglect to set up their own setjmp() and then encounter
+ a png_error() will longjmp here. Since the jmpbuf is then meaningless we
+ abort instead of returning. */
+#ifdef USE_FAR_KEYWORD
+ if (setjmp(jmpbuf))
+ PNG_ABORT();
+ png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#else
+ if (setjmp(png_ptr->jmpbuf))
+ PNG_ABORT();
+#endif
+#endif
+ return (png_ptr);
+}
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+/* Initialize PNG structure for reading, and allocate any memory needed.
+ This interface is deprecated in favour of the png_create_read_struct(),
+ and it will disappear as of libpng-1.3.0. */
+#undef png_read_init
+void PNGAPI
+png_read_init(png_structp png_ptr)
+{
+ /* We only come here via pre-1.0.7-compiled applications */
+ png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
+}
+
+void PNGAPI
+png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver,
+ png_size_t png_struct_size, png_size_t png_info_size)
+{
+ /* We only come here via pre-1.0.12-compiled applications */
+ if(png_ptr == NULL) return;
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ if(png_sizeof(png_struct) > png_struct_size ||
+ png_sizeof(png_info) > png_info_size)
+ {
+ char msg[80];
+ png_ptr->warning_fn=NULL;
+ if (user_png_ver)
+ {
+ png_snprintf(msg, 80,
+ "Application was compiled with png.h from libpng-%.20s",
+ user_png_ver);
+ png_warning(png_ptr, msg);
+ }
+ png_snprintf(msg, 80,
+ "Application is running with png.c from libpng-%.20s",
+ png_libpng_ver);
+ png_warning(png_ptr, msg);
+ }
+#endif
+ if(png_sizeof(png_struct) > png_struct_size)
+ {
+ png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "The png struct allocated by the application for reading is too small.");
+ }
+ if(png_sizeof(png_info) > png_info_size)
+ {
+ png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "The info struct allocated by application for reading is too small.");
+ }
+ png_read_init_3(&png_ptr, user_png_ver, png_struct_size);
+}
+#endif /* PNG_1_0_X || PNG_1_2_X */
+
+void PNGAPI
+png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
+ png_size_t png_struct_size)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf tmp_jmp; /* to save current jump buffer */
+#endif
+
+ int i=0;
+
+ png_structp png_ptr=*ptr_ptr;
+
+ if(png_ptr == NULL) return;
+
+ do
+ {
+ if(user_png_ver[i] != png_libpng_ver[i])
+ {
+#ifdef PNG_LEGACY_SUPPORTED
+ png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+#else
+ png_ptr->warning_fn=NULL;
+ png_warning(png_ptr,
+ "Application uses deprecated png_read_init() and should be recompiled.");
+ break;
+#endif
+ }
+ } while (png_libpng_ver[i++]);
+
+ png_debug(1, "in png_read_init_3\n");
+
+#ifdef PNG_SETJMP_SUPPORTED
+ /* save jump buffer and error functions */
+ png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+ if(png_sizeof(png_struct) > png_struct_size)
+ {
+ png_destroy_struct(png_ptr);
+ *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+ png_ptr = *ptr_ptr;
+ }
+
+ /* reset all variables to 0 */
+ png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+#ifdef PNG_SETJMP_SUPPORTED
+ /* restore jump buffer */
+ png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+
+ /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+ png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+ /* initialize zbuf - compression buffer */
+ png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+ png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)png_ptr->zbuf_size);
+ png_ptr->zstream.zalloc = png_zalloc;
+ png_ptr->zstream.zfree = png_zfree;
+ png_ptr->zstream.opaque = (voidpf)png_ptr;
+
+ switch (inflateInit(&png_ptr->zstream))
+ {
+ case Z_OK: /* Do nothing */ break;
+ case Z_MEM_ERROR:
+ case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break;
+ case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break;
+ default: png_error(png_ptr, "Unknown zlib error");
+ }
+
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+ png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
+}
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read the information before the actual image data. This has been
+ * changed in v0.90 to allow reading a file that already has the magic
+ * bytes read from the stream. You can tell libpng how many bytes have
+ * been read from the beginning of the stream (up to the maximum of 8)
+ * via png_set_sig_bytes(), and we will only check the remaining bytes
+ * here. The application can then have access to the signature bytes we
+ * read if it is determined that this isn't a valid PNG file.
+ */
+void PNGAPI
+png_read_info(png_structp png_ptr, png_infop info_ptr)
+{
+ if(png_ptr == NULL) return;
+ png_debug(1, "in png_read_info\n");
+ /* If we haven't checked all of the PNG signature bytes, do so now. */
+ if (png_ptr->sig_bytes < 8)
+ {
+ png_size_t num_checked = png_ptr->sig_bytes,
+ num_to_check = 8 - num_checked;
+
+ png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
+ png_ptr->sig_bytes = 8;
+
+ if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
+ {
+ if (num_checked < 4 &&
+ png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+ png_error(png_ptr, "Not a PNG file");
+ else
+ png_error(png_ptr, "PNG file corrupted by ASCII conversion");
+ }
+ if (num_checked < 3)
+ png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
+ }
+
+ for(;;)
+ {
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IHDR;
+ PNG_CONST PNG_IDAT;
+ PNG_CONST PNG_IEND;
+ PNG_CONST PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+ PNG_CONST PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+ PNG_CONST PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+ PNG_CONST PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+ PNG_CONST PNG_hIST;
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ PNG_CONST PNG_iCCP;
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ PNG_CONST PNG_iTXt;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+ PNG_CONST PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+ PNG_CONST PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+ PNG_CONST PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+ PNG_CONST PNG_sBIT;
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+ PNG_CONST PNG_sCAL;
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ PNG_CONST PNG_sPLT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ PNG_CONST PNG_sRGB;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ PNG_CONST PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+ PNG_CONST PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ PNG_CONST PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ PNG_CONST PNG_zTXt;
+#endif
+#endif /* PNG_USE_LOCAL_ARRAYS */
+ png_byte chunk_length[4];
+ png_uint_32 length;
+
+ png_read_data(png_ptr, chunk_length, 4);
+ length = png_get_uint_31(png_ptr,chunk_length);
+
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+
+ png_debug2(0, "Reading %s chunk, length=%lu.\n", png_ptr->chunk_name,
+ length);
+
+ /* This should be a binary subdivision search or a hash for
+ * matching the chunk name rather than a linear search.
+ */
+ if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ if(png_ptr->mode & PNG_AFTER_IDAT)
+ png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
+
+ if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
+ png_handle_IHDR(png_ptr, info_ptr, length);
+ else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+ png_handle_IEND(png_ptr, info_ptr, length);
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+ {
+ if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ png_ptr->mode |= PNG_HAVE_IDAT;
+ png_handle_unknown(png_ptr, info_ptr, length);
+ if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ png_ptr->mode |= PNG_HAVE_PLTE;
+ else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before IDAT");
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+ !(png_ptr->mode & PNG_HAVE_PLTE))
+ png_error(png_ptr, "Missing PLTE before IDAT");
+ break;
+ }
+ }
+#endif
+ else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ png_handle_PLTE(png_ptr, info_ptr, length);
+ else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before IDAT");
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+ !(png_ptr->mode & PNG_HAVE_PLTE))
+ png_error(png_ptr, "Missing PLTE before IDAT");
+
+ png_ptr->idat_size = length;
+ png_ptr->mode |= PNG_HAVE_IDAT;
+ break;
+ }
+#if defined(PNG_READ_bKGD_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
+ png_handle_bKGD(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
+ png_handle_cHRM(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
+ png_handle_gAMA(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
+ png_handle_hIST(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
+ png_handle_oFFs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
+ png_handle_pCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+ png_handle_sCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
+ png_handle_pHYs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
+ png_handle_sBIT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+ png_handle_sRGB(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+ png_handle_iCCP(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+ png_handle_sPLT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
+ png_handle_tEXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
+ png_handle_tIME(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
+ png_handle_tRNS(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
+ png_handle_zTXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+ png_handle_iTXt(png_ptr, info_ptr, length);
+#endif
+ else
+ png_handle_unknown(png_ptr, info_ptr, length);
+ }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+/* optional call to update the users info_ptr structure */
+void PNGAPI
+png_read_update_info(png_structp png_ptr, png_infop info_ptr)
+{
+ png_debug(1, "in png_read_update_info\n");
+ if(png_ptr == NULL) return;
+ if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+ png_read_start_row(png_ptr);
+ else
+ png_warning(png_ptr,
+ "Ignoring extra png_read_update_info() call; row buffer not reallocated");
+ png_read_transform_info(png_ptr, info_ptr);
+}
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Initialize palette, background, etc, after transformations
+ * are set, but before any reading takes place. This allows
+ * the user to obtain a gamma-corrected palette, for example.
+ * If the user doesn't call this, we will do it ourselves.
+ */
+void PNGAPI
+png_start_read_image(png_structp png_ptr)
+{
+ png_debug(1, "in png_start_read_image\n");
+ if(png_ptr == NULL) return;
+ if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+ png_read_start_row(png_ptr);
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+void PNGAPI
+png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IDAT;
+ PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
+ 0xff};
+ PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
+#endif
+ int ret;
+ if(png_ptr == NULL) return;
+ png_debug2(1, "in png_read_row (row %lu, pass %d)\n",
+ png_ptr->row_number, png_ptr->pass);
+ if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+ png_read_start_row(png_ptr);
+ if (png_ptr->row_number == 0 && png_ptr->pass == 0)
+ {
+ /* check for transforms that have been set but were defined out */
+#if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_MONO)
+ png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)
+ if (png_ptr->transformations & PNG_FILLER)
+ png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACKSWAP)
+ png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACK)
+ png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)
+ if (png_ptr->transformations & PNG_SHIFT)
+ png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)
+ if (png_ptr->transformations & PNG_BGR)
+ png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_SWAP_BYTES)
+ png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined.");
+#endif
+ }
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+ /* if interlaced and we do not need a new row, combine row and return */
+ if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+ {
+ switch (png_ptr->pass)
+ {
+ case 0:
+ if (png_ptr->row_number & 0x07)
+ {
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 1:
+ if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
+ {
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 2:
+ if ((png_ptr->row_number & 0x07) != 4)
+ {
+ if (dsp_row != NULL && (png_ptr->row_number & 4))
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 3:
+ if ((png_ptr->row_number & 3) || png_ptr->width < 3)
+ {
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 4:
+ if ((png_ptr->row_number & 3) != 2)
+ {
+ if (dsp_row != NULL && (png_ptr->row_number & 2))
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 5:
+ if ((png_ptr->row_number & 1) || png_ptr->width < 2)
+ {
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 6:
+ if (!(png_ptr->row_number & 1))
+ {
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ }
+ }
+#endif
+
+ if (!(png_ptr->mode & PNG_HAVE_IDAT))
+ png_error(png_ptr, "Invalid attempt to read row data");
+
+ png_ptr->zstream.next_out = png_ptr->row_buf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+ do
+ {
+ if (!(png_ptr->zstream.avail_in))
+ {
+ while (!png_ptr->idat_size)
+ {
+ png_byte chunk_length[4];
+
+ png_crc_finish(png_ptr, 0);
+
+ png_read_data(png_ptr, chunk_length, 4);
+ png_ptr->idat_size = png_get_uint_31(png_ptr,chunk_length);
+
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ png_error(png_ptr, "Not enough image data");
+ }
+ png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
+ png_ptr->zstream.next_in = png_ptr->zbuf;
+ if (png_ptr->zbuf_size > png_ptr->idat_size)
+ png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
+ png_crc_read(png_ptr, png_ptr->zbuf,
+ (png_size_t)png_ptr->zstream.avail_in);
+ png_ptr->idat_size -= png_ptr->zstream.avail_in;
+ }
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+ if (ret == Z_STREAM_END)
+ {
+ if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in ||
+ png_ptr->idat_size)
+ png_error(png_ptr, "Extra compressed data");
+ png_ptr->mode |= PNG_AFTER_IDAT;
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+ break;
+ }
+ if (ret != Z_OK)
+ png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
+ "Decompression error");
+
+ } while (png_ptr->zstream.avail_out);
+
+ png_ptr->row_info.color_type = png_ptr->color_type;
+ png_ptr->row_info.width = png_ptr->iwidth;
+ png_ptr->row_info.channels = png_ptr->channels;
+ png_ptr->row_info.bit_depth = png_ptr->bit_depth;
+ png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
+ png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+ png_ptr->row_info.width);
+
+ if(png_ptr->row_buf[0])
+ png_read_filter_row(png_ptr, &(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->prev_row + 1,
+ (int)(png_ptr->row_buf[0]));
+
+ png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+ png_ptr->rowbytes + 1);
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+ (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
+ {
+ /* Intrapixel differencing */
+ png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
+ }
+#endif
+
+
+ if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+ png_do_read_transformations(png_ptr);
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+ /* blow up interlaced rows to full size */
+ if (png_ptr->interlaced &&
+ (png_ptr->transformations & PNG_INTERLACE))
+ {
+ if (png_ptr->pass < 6)
+/* old interface (pre-1.0.9):
+ png_do_read_interlace(&(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
+ */
+ png_do_read_interlace(png_ptr);
+
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ if (row != NULL)
+ png_combine_row(png_ptr, row,
+ png_pass_mask[png_ptr->pass]);
+ }
+ else
+#endif
+ {
+ if (row != NULL)
+ png_combine_row(png_ptr, row, 0xff);
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row, 0xff);
+ }
+ png_read_finish_row(png_ptr);
+
+ if (png_ptr->read_row_fn != NULL)
+ (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read one or more rows of image data. If the image is interlaced,
+ * and png_set_interlace_handling() has been called, the rows need to
+ * contain the contents of the rows from the previous pass. If the
+ * image has alpha or transparency, and png_handle_alpha()[*] has been
+ * called, the rows contents must be initialized to the contents of the
+ * screen.
+ *
+ * "row" holds the actual image, and pixels are placed in it
+ * as they arrive. If the image is displayed after each pass, it will
+ * appear to "sparkle" in. "display_row" can be used to display a
+ * "chunky" progressive image, with finer detail added as it becomes
+ * available. If you do not want this "chunky" display, you may pass
+ * NULL for display_row. If you do not want the sparkle display, and
+ * you have not called png_handle_alpha(), you may pass NULL for rows.
+ * If you have called png_handle_alpha(), and the image has either an
+ * alpha channel or a transparency chunk, you must provide a buffer for
+ * rows. In this case, you do not have to provide a display_row buffer
+ * also, but you may. If the image is not interlaced, or if you have
+ * not called png_set_interlace_handling(), the display_row buffer will
+ * be ignored, so pass NULL to it.
+ *
+ * [*] png_handle_alpha() does not exist yet, as of this version of libpng
+ */
+
+void PNGAPI
+png_read_rows(png_structp png_ptr, png_bytepp row,
+ png_bytepp display_row, png_uint_32 num_rows)
+{
+ png_uint_32 i;
+ png_bytepp rp;
+ png_bytepp dp;
+
+ png_debug(1, "in png_read_rows\n");
+ if(png_ptr == NULL) return;
+ rp = row;
+ dp = display_row;
+ if (rp != NULL && dp != NULL)
+ for (i = 0; i < num_rows; i++)
+ {
+ png_bytep rptr = *rp++;
+ png_bytep dptr = *dp++;
+
+ png_read_row(png_ptr, rptr, dptr);
+ }
+ else if(rp != NULL)
+ for (i = 0; i < num_rows; i++)
+ {
+ png_bytep rptr = *rp;
+ png_read_row(png_ptr, rptr, png_bytep_NULL);
+ rp++;
+ }
+ else if(dp != NULL)
+ for (i = 0; i < num_rows; i++)
+ {
+ png_bytep dptr = *dp;
+ png_read_row(png_ptr, png_bytep_NULL, dptr);
+ dp++;
+ }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read the entire image. If the image has an alpha channel or a tRNS
+ * chunk, and you have called png_handle_alpha()[*], you will need to
+ * initialize the image to the current image that PNG will be overlaying.
+ * We set the num_rows again here, in case it was incorrectly set in
+ * png_read_start_row() by a call to png_read_update_info() or
+ * png_start_read_image() if png_set_interlace_handling() wasn't called
+ * prior to either of these functions like it should have been. You can
+ * only call this function once. If you desire to have an image for
+ * each pass of a interlaced image, use png_read_rows() instead.
+ *
+ * [*] png_handle_alpha() does not exist yet, as of this version of libpng
+ */
+void PNGAPI
+png_read_image(png_structp png_ptr, png_bytepp image)
+{
+ png_uint_32 i,image_height;
+ int pass, j;
+ png_bytepp rp;
+
+ png_debug(1, "in png_read_image\n");
+ if(png_ptr == NULL) return;
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+ pass = png_set_interlace_handling(png_ptr);
+#else
+ if (png_ptr->interlaced)
+ png_error(png_ptr,
+ "Cannot read interlaced image -- interlace handler disabled.");
+ pass = 1;
+#endif
+
+
+ image_height=png_ptr->height;
+ png_ptr->num_rows = image_height; /* Make sure this is set correctly */
+
+ for (j = 0; j < pass; j++)
+ {
+ rp = image;
+ for (i = 0; i < image_height; i++)
+ {
+ png_read_row(png_ptr, *rp, png_bytep_NULL);
+ rp++;
+ }
+ }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read the end of the PNG file. Will not read past the end of the
+ * file, will verify the end is accurate, and will read any comments
+ * or time information at the end of the file, if info is not NULL.
+ */
+void PNGAPI
+png_read_end(png_structp png_ptr, png_infop info_ptr)
+{
+ png_byte chunk_length[4];
+ png_uint_32 length;
+
+ png_debug(1, "in png_read_end\n");
+ if(png_ptr == NULL) return;
+ png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
+
+ do
+ {
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IHDR;
+ PNG_CONST PNG_IDAT;
+ PNG_CONST PNG_IEND;
+ PNG_CONST PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+ PNG_CONST PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+ PNG_CONST PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+ PNG_CONST PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+ PNG_CONST PNG_hIST;
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ PNG_CONST PNG_iCCP;
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ PNG_CONST PNG_iTXt;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+ PNG_CONST PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+ PNG_CONST PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+ PNG_CONST PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+ PNG_CONST PNG_sBIT;
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+ PNG_CONST PNG_sCAL;
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ PNG_CONST PNG_sPLT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ PNG_CONST PNG_sRGB;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ PNG_CONST PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+ PNG_CONST PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ PNG_CONST PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ PNG_CONST PNG_zTXt;
+#endif
+#endif /* PNG_USE_LOCAL_ARRAYS */
+
+ png_read_data(png_ptr, chunk_length, 4);
+ length = png_get_uint_31(png_ptr,chunk_length);
+
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+
+ png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
+
+ if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
+ png_handle_IHDR(png_ptr, info_ptr, length);
+ else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+ png_handle_IEND(png_ptr, info_ptr, length);
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+ {
+ if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
+ png_error(png_ptr, "Too many IDAT's found");
+ }
+ png_handle_unknown(png_ptr, info_ptr, length);
+ if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ png_ptr->mode |= PNG_HAVE_PLTE;
+ }
+#endif
+ else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ /* Zero length IDATs are legal after the last IDAT has been
+ * read, but not after other chunks have been read.
+ */
+ if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
+ png_error(png_ptr, "Too many IDAT's found");
+ png_crc_finish(png_ptr, length);
+ }
+ else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ png_handle_PLTE(png_ptr, info_ptr, length);
+#if defined(PNG_READ_bKGD_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
+ png_handle_bKGD(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
+ png_handle_cHRM(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
+ png_handle_gAMA(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
+ png_handle_hIST(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
+ png_handle_oFFs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
+ png_handle_pCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+ png_handle_sCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
+ png_handle_pHYs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
+ png_handle_sBIT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+ png_handle_sRGB(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+ png_handle_iCCP(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+ png_handle_sPLT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
+ png_handle_tEXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
+ png_handle_tIME(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
+ png_handle_tRNS(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
+ png_handle_zTXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+ png_handle_iTXt(png_ptr, info_ptr, length);
+#endif
+ else
+ png_handle_unknown(png_ptr, info_ptr, length);
+ } while (!(png_ptr->mode & PNG_HAVE_IEND));
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+/* free all memory used by the read */
+void PNGAPI
+png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr,
+ png_infopp end_info_ptr_ptr)
+{
+ png_structp png_ptr = NULL;
+ png_infop info_ptr = NULL, end_info_ptr = NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_free_ptr free_fn;
+ png_voidp mem_ptr;
+#endif
+
+ png_debug(1, "in png_destroy_read_struct\n");
+ if (png_ptr_ptr != NULL)
+ png_ptr = *png_ptr_ptr;
+
+ if (info_ptr_ptr != NULL)
+ info_ptr = *info_ptr_ptr;
+
+ if (end_info_ptr_ptr != NULL)
+ end_info_ptr = *end_info_ptr_ptr;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ free_fn = png_ptr->free_fn;
+ mem_ptr = png_ptr->mem_ptr;
+#endif
+
+ png_read_destroy(png_ptr, info_ptr, end_info_ptr);
+
+ if (info_ptr != NULL)
+ {
+#if defined(PNG_TEXT_SUPPORTED)
+ png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1);
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
+ (png_voidp)mem_ptr);
+#else
+ png_destroy_struct((png_voidp)info_ptr);
+#endif
+ *info_ptr_ptr = NULL;
+ }
+
+ if (end_info_ptr != NULL)
+ {
+#if defined(PNG_READ_TEXT_SUPPORTED)
+ png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1);
+#endif
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn,
+ (png_voidp)mem_ptr);
+#else
+ png_destroy_struct((png_voidp)end_info_ptr);
+#endif
+ *end_info_ptr_ptr = NULL;
+ }
+
+ if (png_ptr != NULL)
+ {
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
+ (png_voidp)mem_ptr);
+#else
+ png_destroy_struct((png_voidp)png_ptr);
+#endif
+ *png_ptr_ptr = NULL;
+ }
+}
+
+/* free all memory used by the read (old method) */
+void /* PRIVATE */
+png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf tmp_jmp;
+#endif
+ png_error_ptr error_fn;
+ png_error_ptr warning_fn;
+ png_voidp error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_free_ptr free_fn;
+#endif
+
+ png_debug(1, "in png_read_destroy\n");
+ if (info_ptr != NULL)
+ png_info_destroy(png_ptr, info_ptr);
+
+ if (end_info_ptr != NULL)
+ png_info_destroy(png_ptr, end_info_ptr);
+
+ png_free(png_ptr, png_ptr->zbuf);
+ png_free(png_ptr, png_ptr->big_row_buf);
+ png_free(png_ptr, png_ptr->prev_row);
+#if defined(PNG_READ_DITHER_SUPPORTED)
+ png_free(png_ptr, png_ptr->palette_lookup);
+ png_free(png_ptr, png_ptr->dither_index);
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ png_free(png_ptr, png_ptr->gamma_table);
+#endif
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ png_free(png_ptr, png_ptr->gamma_from_1);
+ png_free(png_ptr, png_ptr->gamma_to_1);
+#endif
+#ifdef PNG_FREE_ME_SUPPORTED
+ if (png_ptr->free_me & PNG_FREE_PLTE)
+ png_zfree(png_ptr, png_ptr->palette);
+ png_ptr->free_me &= ~PNG_FREE_PLTE;
+#else
+ if (png_ptr->flags & PNG_FLAG_FREE_PLTE)
+ png_zfree(png_ptr, png_ptr->palette);
+ png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
+#endif
+#if defined(PNG_tRNS_SUPPORTED) || \
+ defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+#ifdef PNG_FREE_ME_SUPPORTED
+ if (png_ptr->free_me & PNG_FREE_TRNS)
+ png_free(png_ptr, png_ptr->trans);
+ png_ptr->free_me &= ~PNG_FREE_TRNS;
+#else
+ if (png_ptr->flags & PNG_FLAG_FREE_TRNS)
+ png_free(png_ptr, png_ptr->trans);
+ png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
+#endif
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+#ifdef PNG_FREE_ME_SUPPORTED
+ if (png_ptr->free_me & PNG_FREE_HIST)
+ png_free(png_ptr, png_ptr->hist);
+ png_ptr->free_me &= ~PNG_FREE_HIST;
+#else
+ if (png_ptr->flags & PNG_FLAG_FREE_HIST)
+ png_free(png_ptr, png_ptr->hist);
+ png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
+#endif
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (png_ptr->gamma_16_table != NULL)
+ {
+ int i;
+ int istop = (1 << (8 - png_ptr->gamma_shift));
+ for (i = 0; i < istop; i++)
+ {
+ png_free(png_ptr, png_ptr->gamma_16_table[i]);
+ }
+ png_free(png_ptr, png_ptr->gamma_16_table);
+ }
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->gamma_16_from_1 != NULL)
+ {
+ int i;
+ int istop = (1 << (8 - png_ptr->gamma_shift));
+ for (i = 0; i < istop; i++)
+ {
+ png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
+ }
+ png_free(png_ptr, png_ptr->gamma_16_from_1);
+ }
+ if (png_ptr->gamma_16_to_1 != NULL)
+ {
+ int i;
+ int istop = (1 << (8 - png_ptr->gamma_shift));
+ for (i = 0; i < istop; i++)
+ {
+ png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
+ }
+ png_free(png_ptr, png_ptr->gamma_16_to_1);
+ }
+#endif
+#endif
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+ png_free(png_ptr, png_ptr->time_buffer);
+#endif
+
+ inflateEnd(&png_ptr->zstream);
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+ png_free(png_ptr, png_ptr->save_buffer);
+#endif
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+#ifdef PNG_TEXT_SUPPORTED
+ png_free(png_ptr, png_ptr->current_text);
+#endif /* PNG_TEXT_SUPPORTED */
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+ /* Save the important info out of the png_struct, in case it is
+ * being used again.
+ */
+#ifdef PNG_SETJMP_SUPPORTED
+ png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+ error_fn = png_ptr->error_fn;
+ warning_fn = png_ptr->warning_fn;
+ error_ptr = png_ptr->error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ free_fn = png_ptr->free_fn;
+#endif
+
+ png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+ png_ptr->error_fn = error_fn;
+ png_ptr->warning_fn = warning_fn;
+ png_ptr->error_ptr = error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_ptr->free_fn = free_fn;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+ png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+
+}
+
+void PNGAPI
+png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn)
+{
+ if(png_ptr == NULL) return;
+ png_ptr->read_row_fn = read_row_fn;
+}
+
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+void PNGAPI
+png_read_png(png_structp png_ptr, png_infop info_ptr,
+ int transforms,
+ voidp params)
+{
+ int row;
+
+ if(png_ptr == NULL) return;
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+ /* invert the alpha channel from opacity to transparency
+ */
+ if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+ png_set_invert_alpha(png_ptr);
+#endif
+
+ /* png_read_info() gives us all of the information from the
+ * PNG file before the first IDAT (image data chunk).
+ */
+ png_read_info(png_ptr, info_ptr);
+ if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
+ png_error(png_ptr,"Image is too high to process with png_read_png()");
+
+ /* -------------- image transformations start here ------------------- */
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+ /* tell libpng to strip 16 bit/color files down to 8 bits per color
+ */
+ if (transforms & PNG_TRANSFORM_STRIP_16)
+ png_set_strip_16(png_ptr);
+#endif
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+ /* Strip alpha bytes from the input data without combining with
+ * the background (not recommended).
+ */
+ if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
+ png_set_strip_alpha(png_ptr);
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
+ /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
+ * byte into separate bytes (useful for paletted and grayscale images).
+ */
+ if (transforms & PNG_TRANSFORM_PACKING)
+ png_set_packing(png_ptr);
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ /* Change the order of packed pixels to least significant bit first
+ * (not useful if you are using png_set_packing).
+ */
+ if (transforms & PNG_TRANSFORM_PACKSWAP)
+ png_set_packswap(png_ptr);
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+ /* Expand paletted colors into true RGB triplets
+ * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel
+ * Expand paletted or RGB images with transparency to full alpha
+ * channels so the data will be available as RGBA quartets.
+ */
+ if (transforms & PNG_TRANSFORM_EXPAND)
+ if ((png_ptr->bit_depth < 8) ||
+ (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
+ (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
+ png_set_expand(png_ptr);
+#endif
+
+ /* We don't handle background color or gamma transformation or dithering.
+ */
+
+#if defined(PNG_READ_INVERT_SUPPORTED)
+ /* invert monochrome files to have 0 as white and 1 as black
+ */
+ if (transforms & PNG_TRANSFORM_INVERT_MONO)
+ png_set_invert_mono(png_ptr);
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+ /* If you want to shift the pixel values from the range [0,255] or
+ * [0,65535] to the original [0,7] or [0,31], or whatever range the
+ * colors were originally in:
+ */
+ if ((transforms & PNG_TRANSFORM_SHIFT)
+ && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
+ {
+ png_color_8p sig_bit;
+
+ png_get_sBIT(png_ptr, info_ptr, &sig_bit);
+ png_set_shift(png_ptr, sig_bit);
+ }
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED)
+ /* flip the RGB pixels to BGR (or RGBA to BGRA)
+ */
+ if (transforms & PNG_TRANSFORM_BGR)
+ png_set_bgr(png_ptr);
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+ /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
+ */
+ if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+ png_set_swap_alpha(png_ptr);
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED)
+ /* swap bytes of 16 bit files to least significant byte first
+ */
+ if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+ png_set_swap(png_ptr);
+#endif
+
+ /* We don't handle adding filler bytes */
+
+ /* Optional call to gamma correct and add the background to the palette
+ * and update info structure. REQUIRED if you are expecting libpng to
+ * update the palette for you (i.e., you selected such a transform above).
+ */
+ png_read_update_info(png_ptr, info_ptr);
+
+ /* -------------- image transformations end here ------------------- */
+
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
+#endif
+ if(info_ptr->row_pointers == NULL)
+ {
+ info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
+ info_ptr->height * png_sizeof(png_bytep));
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_ROWS;
+#endif
+ for (row = 0; row < (int)info_ptr->height; row++)
+ {
+ info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
+ png_get_rowbytes(png_ptr, info_ptr));
+ }
+ }
+
+ png_read_image(png_ptr, info_ptr->row_pointers);
+ info_ptr->valid |= PNG_INFO_IDAT;
+
+ /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
+ png_read_end(png_ptr, info_ptr);
+
+ transforms = transforms; /* quiet compiler warnings */
+ params = params;
+
+}
+#endif /* PNG_INFO_IMAGE_SUPPORTED */
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED */
diff --git a/src/libpng/pngrio.c b/src/libpng/pngrio.c
new file mode 100644
index 0000000..7d2522f
--- /dev/null
+++ b/src/libpng/pngrio.c
@@ -0,0 +1,167 @@
+
+/* pngrio.c - functions for data input
+ *
+ * Last changed in libpng 1.2.13 November 13, 2006
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2006 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all input. Users who need
+ * special handling are expected to write a function that has the same
+ * arguments as this and performs a similar function, but that possibly
+ * has a different input method. Note that you shouldn't change this
+ * function, but rather write a replacement function and then make
+ * libpng use it at run time with png_set_read_fn(...).
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED)
+
+/* Read the data from whatever input you are using. The default routine
+ reads from a file pointer. Note that this routine sometimes gets called
+ with very small lengths, so you should implement some kind of simple
+ buffering if you are using unbuffered reads. This should never be asked
+ to read more then 64K on a 16 bit machine. */
+void /* PRIVATE */
+png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ png_debug1(4,"reading %d bytes\n", (int)length);
+ if (png_ptr->read_data_fn != NULL)
+ (*(png_ptr->read_data_fn))(png_ptr, data, length);
+ else
+ png_error(png_ptr, "Call to NULL read function");
+}
+
+#if !defined(PNG_NO_STDIO)
+/* This is the function that does the actual reading of data. If you are
+ not reading from a standard C stream, you should create a replacement
+ read_data function and use it at run time with png_set_read_fn(), rather
+ than changing the library. */
+#ifndef USE_FAR_KEYWORD
+void PNGAPI
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ png_size_t check;
+
+ if(png_ptr == NULL) return;
+ /* fread() returns 0 on error, so it is OK to store this in a png_size_t
+ * instead of an int, which is what fread() actually returns.
+ */
+#if defined(_WIN32_WCE)
+ if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+ check = 0;
+#else
+ check = (png_size_t)fread(data, (png_size_t)1, length,
+ (png_FILE_p)png_ptr->io_ptr);
+#endif
+
+ if (check != length)
+ png_error(png_ptr, "Read Error");
+}
+#else
+/* this is the model-independent version. Since the standard I/O library
+ can't handle far buffers in the medium and small models, we have to copy
+ the data.
+*/
+
+#define NEAR_BUF_SIZE 1024
+#define MIN(a,b) (a <= b ? a : b)
+
+static void PNGAPI
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ int check;
+ png_byte *n_data;
+ png_FILE_p io_ptr;
+
+ if(png_ptr == NULL) return;
+ /* Check if data really is near. If so, use usual code. */
+ n_data = (png_byte *)CVT_PTR_NOCHECK(data);
+ io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
+ if ((png_bytep)n_data == data)
+ {
+#if defined(_WIN32_WCE)
+ if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+ check = 0;
+#else
+ check = fread(n_data, 1, length, io_ptr);
+#endif
+ }
+ else
+ {
+ png_byte buf[NEAR_BUF_SIZE];
+ png_size_t read, remaining, err;
+ check = 0;
+ remaining = length;
+ do
+ {
+ read = MIN(NEAR_BUF_SIZE, remaining);
+#if defined(_WIN32_WCE)
+ if ( !ReadFile((HANDLE)(io_ptr), buf, read, &err, NULL) )
+ err = 0;
+#else
+ err = fread(buf, (png_size_t)1, read, io_ptr);
+#endif
+ png_memcpy(data, buf, read); /* copy far buffer to near buffer */
+ if(err != read)
+ break;
+ else
+ check += err;
+ data += read;
+ remaining -= read;
+ }
+ while (remaining != 0);
+ }
+ if ((png_uint_32)check != (png_uint_32)length)
+ png_error(png_ptr, "read Error");
+}
+#endif
+#endif
+
+/* This function allows the application to supply a new input function
+ for libpng if standard C streams aren't being used.
+
+ This function takes as its arguments:
+ png_ptr - pointer to a png input data structure
+ io_ptr - pointer to user supplied structure containing info about
+ the input functions. May be NULL.
+ read_data_fn - pointer to a new input function that takes as its
+ arguments a pointer to a png_struct, a pointer to
+ a location where input data can be stored, and a 32-bit
+ unsigned int that is the number of bytes to be read.
+ To exit and output any fatal error messages the new write
+ function should call png_error(png_ptr, "Error msg"). */
+void PNGAPI
+png_set_read_fn(png_structp png_ptr, png_voidp io_ptr,
+ png_rw_ptr read_data_fn)
+{
+ if(png_ptr == NULL) return;
+ png_ptr->io_ptr = io_ptr;
+
+#if !defined(PNG_NO_STDIO)
+ if (read_data_fn != NULL)
+ png_ptr->read_data_fn = read_data_fn;
+ else
+ png_ptr->read_data_fn = png_default_read_data;
+#else
+ png_ptr->read_data_fn = read_data_fn;
+#endif
+
+ /* It is an error to write to a read device */
+ if (png_ptr->write_data_fn != NULL)
+ {
+ png_ptr->write_data_fn = NULL;
+ png_warning(png_ptr,
+ "It's an error to set both read_data_fn and write_data_fn in the ");
+ png_warning(png_ptr,
+ "same structure. Resetting write_data_fn to NULL.");
+ }
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+ png_ptr->output_flush_fn = NULL;
+#endif
+}
+#endif /* PNG_READ_SUPPORTED */
diff --git a/src/libpng/pngrtran.c b/src/libpng/pngrtran.c
new file mode 100644
index 0000000..cda3921
--- /dev/null
+++ b/src/libpng/pngrtran.c
@@ -0,0 +1,4284 @@
+
+/* pngrtran.c - transforms the data in a row for PNG readers
+ *
+ * Last changed in libpng 1.2.22 [October 13, 2007]
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file contains functions optionally called by an application
+ * in order to tell libpng how to handle data when reading a PNG.
+ * Transformations that are used in both reading and writing are
+ * in pngtrans.c.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED)
+
+/* Set the action on getting a CRC error for an ancillary or critical chunk. */
+void PNGAPI
+png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action)
+{
+ png_debug(1, "in png_set_crc_action\n");
+ /* Tell libpng how we react to CRC errors in critical chunks */
+ if(png_ptr == NULL) return;
+ switch (crit_action)
+ {
+ case PNG_CRC_NO_CHANGE: /* leave setting as is */
+ break;
+ case PNG_CRC_WARN_USE: /* warn/use data */
+ png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
+ png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE;
+ break;
+ case PNG_CRC_QUIET_USE: /* quiet/use data */
+ png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
+ png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE |
+ PNG_FLAG_CRC_CRITICAL_IGNORE;
+ break;
+ case PNG_CRC_WARN_DISCARD: /* not a valid action for critical data */
+ png_warning(png_ptr, "Can't discard critical data on CRC error.");
+ case PNG_CRC_ERROR_QUIT: /* error/quit */
+ case PNG_CRC_DEFAULT:
+ default:
+ png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
+ break;
+ }
+
+ switch (ancil_action)
+ {
+ case PNG_CRC_NO_CHANGE: /* leave setting as is */
+ break;
+ case PNG_CRC_WARN_USE: /* warn/use data */
+ png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+ png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE;
+ break;
+ case PNG_CRC_QUIET_USE: /* quiet/use data */
+ png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+ png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE |
+ PNG_FLAG_CRC_ANCILLARY_NOWARN;
+ break;
+ case PNG_CRC_ERROR_QUIT: /* error/quit */
+ png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+ png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_NOWARN;
+ break;
+ case PNG_CRC_WARN_DISCARD: /* warn/discard data */
+ case PNG_CRC_DEFAULT:
+ default:
+ png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+ break;
+ }
+}
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
+ defined(PNG_FLOATING_POINT_SUPPORTED)
+/* handle alpha and tRNS via a background color */
+void PNGAPI
+png_set_background(png_structp png_ptr,
+ png_color_16p background_color, int background_gamma_code,
+ int need_expand, double background_gamma)
+{
+ png_debug(1, "in png_set_background\n");
+ if(png_ptr == NULL) return;
+ if (background_gamma_code == PNG_BACKGROUND_GAMMA_UNKNOWN)
+ {
+ png_warning(png_ptr, "Application must supply a known background gamma");
+ return;
+ }
+
+ png_ptr->transformations |= PNG_BACKGROUND;
+ png_memcpy(&(png_ptr->background), background_color,
+ png_sizeof(png_color_16));
+ png_ptr->background_gamma = (float)background_gamma;
+ png_ptr->background_gamma_type = (png_byte)(background_gamma_code);
+ png_ptr->transformations |= (need_expand ? PNG_BACKGROUND_EXPAND : 0);
+}
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+/* strip 16 bit depth files to 8 bit depth */
+void PNGAPI
+png_set_strip_16(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_strip_16\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_16_TO_8;
+}
+#endif
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+void PNGAPI
+png_set_strip_alpha(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_strip_alpha\n");
+ if(png_ptr == NULL) return;
+ png_ptr->flags |= PNG_FLAG_STRIP_ALPHA;
+}
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+/* Dither file to 8 bit. Supply a palette, the current number
+ * of elements in the palette, the maximum number of elements
+ * allowed, and a histogram if possible. If the current number
+ * of colors is greater then the maximum number, the palette will be
+ * modified to fit in the maximum number. "full_dither" indicates
+ * whether we need a dithering cube set up for RGB images, or if we
+ * simply are reducing the number of colors in a paletted image.
+ */
+
+typedef struct png_dsort_struct
+{
+ struct png_dsort_struct FAR * next;
+ png_byte left;
+ png_byte right;
+} png_dsort;
+typedef png_dsort FAR * png_dsortp;
+typedef png_dsort FAR * FAR * png_dsortpp;
+
+void PNGAPI
+png_set_dither(png_structp png_ptr, png_colorp palette,
+ int num_palette, int maximum_colors, png_uint_16p histogram,
+ int full_dither)
+{
+ png_debug(1, "in png_set_dither\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_DITHER;
+
+ if (!full_dither)
+ {
+ int i;
+
+ png_ptr->dither_index = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)(num_palette * png_sizeof (png_byte)));
+ for (i = 0; i < num_palette; i++)
+ png_ptr->dither_index[i] = (png_byte)i;
+ }
+
+ if (num_palette > maximum_colors)
+ {
+ if (histogram != NULL)
+ {
+ /* This is easy enough, just throw out the least used colors.
+ Perhaps not the best solution, but good enough. */
+
+ int i;
+
+ /* initialize an array to sort colors */
+ png_ptr->dither_sort = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)(num_palette * png_sizeof (png_byte)));
+
+ /* initialize the dither_sort array */
+ for (i = 0; i < num_palette; i++)
+ png_ptr->dither_sort[i] = (png_byte)i;
+
+ /* Find the least used palette entries by starting a
+ bubble sort, and running it until we have sorted
+ out enough colors. Note that we don't care about
+ sorting all the colors, just finding which are
+ least used. */
+
+ for (i = num_palette - 1; i >= maximum_colors; i--)
+ {
+ int done; /* to stop early if the list is pre-sorted */
+ int j;
+
+ done = 1;
+ for (j = 0; j < i; j++)
+ {
+ if (histogram[png_ptr->dither_sort[j]]
+ < histogram[png_ptr->dither_sort[j + 1]])
+ {
+ png_byte t;
+
+ t = png_ptr->dither_sort[j];
+ png_ptr->dither_sort[j] = png_ptr->dither_sort[j + 1];
+ png_ptr->dither_sort[j + 1] = t;
+ done = 0;
+ }
+ }
+ if (done)
+ break;
+ }
+
+ /* swap the palette around, and set up a table, if necessary */
+ if (full_dither)
+ {
+ int j = num_palette;
+
+ /* put all the useful colors within the max, but don't
+ move the others */
+ for (i = 0; i < maximum_colors; i++)
+ {
+ if ((int)png_ptr->dither_sort[i] >= maximum_colors)
+ {
+ do
+ j--;
+ while ((int)png_ptr->dither_sort[j] >= maximum_colors);
+ palette[i] = palette[j];
+ }
+ }
+ }
+ else
+ {
+ int j = num_palette;
+
+ /* move all the used colors inside the max limit, and
+ develop a translation table */
+ for (i = 0; i < maximum_colors; i++)
+ {
+ /* only move the colors we need to */
+ if ((int)png_ptr->dither_sort[i] >= maximum_colors)
+ {
+ png_color tmp_color;
+
+ do
+ j--;
+ while ((int)png_ptr->dither_sort[j] >= maximum_colors);
+
+ tmp_color = palette[j];
+ palette[j] = palette[i];
+ palette[i] = tmp_color;
+ /* indicate where the color went */
+ png_ptr->dither_index[j] = (png_byte)i;
+ png_ptr->dither_index[i] = (png_byte)j;
+ }
+ }
+
+ /* find closest color for those colors we are not using */
+ for (i = 0; i < num_palette; i++)
+ {
+ if ((int)png_ptr->dither_index[i] >= maximum_colors)
+ {
+ int min_d, k, min_k, d_index;
+
+ /* find the closest color to one we threw out */
+ d_index = png_ptr->dither_index[i];
+ min_d = PNG_COLOR_DIST(palette[d_index], palette[0]);
+ for (k = 1, min_k = 0; k < maximum_colors; k++)
+ {
+ int d;
+
+ d = PNG_COLOR_DIST(palette[d_index], palette[k]);
+
+ if (d < min_d)
+ {
+ min_d = d;
+ min_k = k;
+ }
+ }
+ /* point to closest color */
+ png_ptr->dither_index[i] = (png_byte)min_k;
+ }
+ }
+ }
+ png_free(png_ptr, png_ptr->dither_sort);
+ png_ptr->dither_sort=NULL;
+ }
+ else
+ {
+ /* This is much harder to do simply (and quickly). Perhaps
+ we need to go through a median cut routine, but those
+ don't always behave themselves with only a few colors
+ as input. So we will just find the closest two colors,
+ and throw out one of them (chosen somewhat randomly).
+ [We don't understand this at all, so if someone wants to
+ work on improving it, be our guest - AED, GRP]
+ */
+ int i;
+ int max_d;
+ int num_new_palette;
+ png_dsortp t;
+ png_dsortpp hash;
+
+ t=NULL;
+
+ /* initialize palette index arrays */
+ png_ptr->index_to_palette = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)(num_palette * png_sizeof (png_byte)));
+ png_ptr->palette_to_index = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)(num_palette * png_sizeof (png_byte)));
+
+ /* initialize the sort array */
+ for (i = 0; i < num_palette; i++)
+ {
+ png_ptr->index_to_palette[i] = (png_byte)i;
+ png_ptr->palette_to_index[i] = (png_byte)i;
+ }
+
+ hash = (png_dsortpp)png_malloc(png_ptr, (png_uint_32)(769 *
+ png_sizeof (png_dsortp)));
+ for (i = 0; i < 769; i++)
+ hash[i] = NULL;
+/* png_memset(hash, 0, 769 * png_sizeof (png_dsortp)); */
+
+ num_new_palette = num_palette;
+
+ /* initial wild guess at how far apart the farthest pixel
+ pair we will be eliminating will be. Larger
+ numbers mean more areas will be allocated, Smaller
+ numbers run the risk of not saving enough data, and
+ having to do this all over again.
+
+ I have not done extensive checking on this number.
+ */
+ max_d = 96;
+
+ while (num_new_palette > maximum_colors)
+ {
+ for (i = 0; i < num_new_palette - 1; i++)
+ {
+ int j;
+
+ for (j = i + 1; j < num_new_palette; j++)
+ {
+ int d;
+
+ d = PNG_COLOR_DIST(palette[i], palette[j]);
+
+ if (d <= max_d)
+ {
+
+ t = (png_dsortp)png_malloc_warn(png_ptr,
+ (png_uint_32)(png_sizeof(png_dsort)));
+ if (t == NULL)
+ break;
+ t->next = hash[d];
+ t->left = (png_byte)i;
+ t->right = (png_byte)j;
+ hash[d] = t;
+ }
+ }
+ if (t == NULL)
+ break;
+ }
+
+ if (t != NULL)
+ for (i = 0; i <= max_d; i++)
+ {
+ if (hash[i] != NULL)
+ {
+ png_dsortp p;
+
+ for (p = hash[i]; p; p = p->next)
+ {
+ if ((int)png_ptr->index_to_palette[p->left]
+ < num_new_palette &&
+ (int)png_ptr->index_to_palette[p->right]
+ < num_new_palette)
+ {
+ int j, next_j;
+
+ if (num_new_palette & 0x01)
+ {
+ j = p->left;
+ next_j = p->right;
+ }
+ else
+ {
+ j = p->right;
+ next_j = p->left;
+ }
+
+ num_new_palette--;
+ palette[png_ptr->index_to_palette[j]]
+ = palette[num_new_palette];
+ if (!full_dither)
+ {
+ int k;
+
+ for (k = 0; k < num_palette; k++)
+ {
+ if (png_ptr->dither_index[k] ==
+ png_ptr->index_to_palette[j])
+ png_ptr->dither_index[k] =
+ png_ptr->index_to_palette[next_j];
+ if ((int)png_ptr->dither_index[k] ==
+ num_new_palette)
+ png_ptr->dither_index[k] =
+ png_ptr->index_to_palette[j];
+ }
+ }
+
+ png_ptr->index_to_palette[png_ptr->palette_to_index
+ [num_new_palette]] = png_ptr->index_to_palette[j];
+ png_ptr->palette_to_index[png_ptr->index_to_palette[j]]
+ = png_ptr->palette_to_index[num_new_palette];
+
+ png_ptr->index_to_palette[j] = (png_byte)num_new_palette;
+ png_ptr->palette_to_index[num_new_palette] = (png_byte)j;
+ }
+ if (num_new_palette <= maximum_colors)
+ break;
+ }
+ if (num_new_palette <= maximum_colors)
+ break;
+ }
+ }
+
+ for (i = 0; i < 769; i++)
+ {
+ if (hash[i] != NULL)
+ {
+ png_dsortp p = hash[i];
+ while (p)
+ {
+ t = p->next;
+ png_free(png_ptr, p);
+ p = t;
+ }
+ }
+ hash[i] = 0;
+ }
+ max_d += 96;
+ }
+ png_free(png_ptr, hash);
+ png_free(png_ptr, png_ptr->palette_to_index);
+ png_free(png_ptr, png_ptr->index_to_palette);
+ png_ptr->palette_to_index=NULL;
+ png_ptr->index_to_palette=NULL;
+ }
+ num_palette = maximum_colors;
+ }
+ if (png_ptr->palette == NULL)
+ {
+ png_ptr->palette = palette;
+ }
+ png_ptr->num_palette = (png_uint_16)num_palette;
+
+ if (full_dither)
+ {
+ int i;
+ png_bytep distance;
+ int total_bits = PNG_DITHER_RED_BITS + PNG_DITHER_GREEN_BITS +
+ PNG_DITHER_BLUE_BITS;
+ int num_red = (1 << PNG_DITHER_RED_BITS);
+ int num_green = (1 << PNG_DITHER_GREEN_BITS);
+ int num_blue = (1 << PNG_DITHER_BLUE_BITS);
+ png_size_t num_entries = ((png_size_t)1 << total_bits);
+
+ png_ptr->palette_lookup = (png_bytep )png_malloc(png_ptr,
+ (png_uint_32)(num_entries * png_sizeof (png_byte)));
+
+ png_memset(png_ptr->palette_lookup, 0, num_entries *
+ png_sizeof (png_byte));
+
+ distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries *
+ png_sizeof(png_byte)));
+
+ png_memset(distance, 0xff, num_entries * png_sizeof(png_byte));
+
+ for (i = 0; i < num_palette; i++)
+ {
+ int ir, ig, ib;
+ int r = (palette[i].red >> (8 - PNG_DITHER_RED_BITS));
+ int g = (palette[i].green >> (8 - PNG_DITHER_GREEN_BITS));
+ int b = (palette[i].blue >> (8 - PNG_DITHER_BLUE_BITS));
+
+ for (ir = 0; ir < num_red; ir++)
+ {
+ /* int dr = abs(ir - r); */
+ int dr = ((ir > r) ? ir - r : r - ir);
+ int index_r = (ir << (PNG_DITHER_BLUE_BITS + PNG_DITHER_GREEN_BITS));
+
+ for (ig = 0; ig < num_green; ig++)
+ {
+ /* int dg = abs(ig - g); */
+ int dg = ((ig > g) ? ig - g : g - ig);
+ int dt = dr + dg;
+ int dm = ((dr > dg) ? dr : dg);
+ int index_g = index_r | (ig << PNG_DITHER_BLUE_BITS);
+
+ for (ib = 0; ib < num_blue; ib++)
+ {
+ int d_index = index_g | ib;
+ /* int db = abs(ib - b); */
+ int db = ((ib > b) ? ib - b : b - ib);
+ int dmax = ((dm > db) ? dm : db);
+ int d = dmax + dt + db;
+
+ if (d < (int)distance[d_index])
+ {
+ distance[d_index] = (png_byte)d;
+ png_ptr->palette_lookup[d_index] = (png_byte)i;
+ }
+ }
+ }
+ }
+ }
+
+ png_free(png_ptr, distance);
+ }
+}
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+/* Transform the image from the file_gamma to the screen_gamma. We
+ * only do transformations on images where the file_gamma and screen_gamma
+ * are not close reciprocals, otherwise it slows things down slightly, and
+ * also needlessly introduces small errors.
+ *
+ * We will turn off gamma transformation later if no semitransparent entries
+ * are present in the tRNS array for palette images. We can't do it here
+ * because we don't necessarily have the tRNS chunk yet.
+ */
+void PNGAPI
+png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma)
+{
+ png_debug(1, "in png_set_gamma\n");
+ if(png_ptr == NULL) return;
+ if ((fabs(scrn_gamma * file_gamma - 1.0) > PNG_GAMMA_THRESHOLD) ||
+ (png_ptr->color_type & PNG_COLOR_MASK_ALPHA) ||
+ (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE))
+ png_ptr->transformations |= PNG_GAMMA;
+ png_ptr->gamma = (float)file_gamma;
+ png_ptr->screen_gamma = (float)scrn_gamma;
+}
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+/* Expand paletted images to RGB, expand grayscale images of
+ * less than 8-bit depth to 8-bit depth, and expand tRNS chunks
+ * to alpha channels.
+ */
+void PNGAPI
+png_set_expand(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_expand\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
+#ifdef PNG_WARN_UNINITIALIZED_ROW
+ png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+#endif
+}
+
+/* GRR 19990627: the following three functions currently are identical
+ * to png_set_expand(). However, it is entirely reasonable that someone
+ * might wish to expand an indexed image to RGB but *not* expand a single,
+ * fully transparent palette entry to a full alpha channel--perhaps instead
+ * convert tRNS to the grayscale/RGB format (16-bit RGB value), or replace
+ * the transparent color with a particular RGB value, or drop tRNS entirely.
+ * IOW, a future version of the library may make the transformations flag
+ * a bit more fine-grained, with separate bits for each of these three
+ * functions.
+ *
+ * More to the point, these functions make it obvious what libpng will be
+ * doing, whereas "expand" can (and does) mean any number of things.
+ *
+ * GRP 20060307: In libpng-1.4.0, png_set_gray_1_2_4_to_8() was modified
+ * to expand only the sample depth but not to expand the tRNS to alpha.
+ */
+
+/* Expand paletted images to RGB. */
+void PNGAPI
+png_set_palette_to_rgb(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_palette_to_rgb\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
+#ifdef PNG_WARN_UNINITIALIZED_ROW
+ png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+#endif
+}
+
+#if !defined(PNG_1_0_X)
+/* Expand grayscale images of less than 8-bit depth to 8 bits. */
+void PNGAPI
+png_set_expand_gray_1_2_4_to_8(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_expand_gray_1_2_4_to_8\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_EXPAND;
+#ifdef PNG_WARN_UNINITIALIZED_ROW
+ png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+#endif
+}
+#endif
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+/* Expand grayscale images of less than 8-bit depth to 8 bits. */
+/* Deprecated as of libpng-1.2.9 */
+void PNGAPI
+png_set_gray_1_2_4_to_8(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_gray_1_2_4_to_8\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
+}
+#endif
+
+
+/* Expand tRNS chunks to alpha channels. */
+void PNGAPI
+png_set_tRNS_to_alpha(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_tRNS_to_alpha\n");
+ png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
+#ifdef PNG_WARN_UNINITIALIZED_ROW
+ png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+#endif
+}
+#endif /* defined(PNG_READ_EXPAND_SUPPORTED) */
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+void PNGAPI
+png_set_gray_to_rgb(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_gray_to_rgb\n");
+ png_ptr->transformations |= PNG_GRAY_TO_RGB;
+#ifdef PNG_WARN_UNINITIALIZED_ROW
+ png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+#endif
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+#if defined(PNG_FLOATING_POINT_SUPPORTED)
+/* Convert a RGB image to a grayscale of the same width. This allows us,
+ * for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image.
+ */
+
+void PNGAPI
+png_set_rgb_to_gray(png_structp png_ptr, int error_action, double red,
+ double green)
+{
+ int red_fixed = (int)((float)red*100000.0 + 0.5);
+ int green_fixed = (int)((float)green*100000.0 + 0.5);
+ if(png_ptr == NULL) return;
+ png_set_rgb_to_gray_fixed(png_ptr, error_action, red_fixed, green_fixed);
+}
+#endif
+
+void PNGAPI
+png_set_rgb_to_gray_fixed(png_structp png_ptr, int error_action,
+ png_fixed_point red, png_fixed_point green)
+{
+ png_debug(1, "in png_set_rgb_to_gray\n");
+ if(png_ptr == NULL) return;
+ switch(error_action)
+ {
+ case 1: png_ptr->transformations |= PNG_RGB_TO_GRAY;
+ break;
+ case 2: png_ptr->transformations |= PNG_RGB_TO_GRAY_WARN;
+ break;
+ case 3: png_ptr->transformations |= PNG_RGB_TO_GRAY_ERR;
+ }
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+ png_ptr->transformations |= PNG_EXPAND;
+#else
+ {
+ png_warning(png_ptr, "Cannot do RGB_TO_GRAY without EXPAND_SUPPORTED.");
+ png_ptr->transformations &= ~PNG_RGB_TO_GRAY;
+ }
+#endif
+ {
+ png_uint_16 red_int, green_int;
+ if(red < 0 || green < 0)
+ {
+ red_int = 6968; /* .212671 * 32768 + .5 */
+ green_int = 23434; /* .715160 * 32768 + .5 */
+ }
+ else if(red + green < 100000L)
+ {
+ red_int = (png_uint_16)(((png_uint_32)red*32768L)/100000L);
+ green_int = (png_uint_16)(((png_uint_32)green*32768L)/100000L);
+ }
+ else
+ {
+ png_warning(png_ptr, "ignoring out of range rgb_to_gray coefficients");
+ red_int = 6968;
+ green_int = 23434;
+ }
+ png_ptr->rgb_to_gray_red_coeff = red_int;
+ png_ptr->rgb_to_gray_green_coeff = green_int;
+ png_ptr->rgb_to_gray_blue_coeff = (png_uint_16)(32768-red_int-green_int);
+ }
+}
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_LEGACY_SUPPORTED)
+void PNGAPI
+png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
+ read_user_transform_fn)
+{
+ png_debug(1, "in png_set_read_user_transform_fn\n");
+ if(png_ptr == NULL) return;
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+ png_ptr->transformations |= PNG_USER_TRANSFORM;
+ png_ptr->read_user_transform_fn = read_user_transform_fn;
+#endif
+#ifdef PNG_LEGACY_SUPPORTED
+ if(read_user_transform_fn)
+ png_warning(png_ptr,
+ "This version of libpng does not support user transforms");
+#endif
+}
+#endif
+
+/* Initialize everything needed for the read. This includes modifying
+ * the palette.
+ */
+void /* PRIVATE */
+png_init_read_transformations(png_structp png_ptr)
+{
+ png_debug(1, "in png_init_read_transformations\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if(png_ptr != NULL)
+#endif
+ {
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || defined(PNG_READ_SHIFT_SUPPORTED) \
+ || defined(PNG_READ_GAMMA_SUPPORTED)
+ int color_type = png_ptr->color_type;
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+ /* Detect gray background and attempt to enable optimization
+ * for gray --> RGB case */
+ /* Note: if PNG_BACKGROUND_EXPAND is set and color_type is either RGB or
+ * RGB_ALPHA (in which case need_expand is superfluous anyway), the
+ * background color might actually be gray yet not be flagged as such.
+ * This is not a problem for the current code, which uses
+ * PNG_BACKGROUND_IS_GRAY only to decide when to do the
+ * png_do_gray_to_rgb() transformation.
+ */
+ if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
+ !(color_type & PNG_COLOR_MASK_COLOR))
+ {
+ png_ptr->mode |= PNG_BACKGROUND_IS_GRAY;
+ } else if ((png_ptr->transformations & PNG_BACKGROUND) &&
+ !(png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
+ (png_ptr->transformations & PNG_GRAY_TO_RGB) &&
+ png_ptr->background.red == png_ptr->background.green &&
+ png_ptr->background.red == png_ptr->background.blue)
+ {
+ png_ptr->mode |= PNG_BACKGROUND_IS_GRAY;
+ png_ptr->background.gray = png_ptr->background.red;
+ }
+#endif
+
+ if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
+ (png_ptr->transformations & PNG_EXPAND))
+ {
+ if (!(color_type & PNG_COLOR_MASK_COLOR)) /* i.e., GRAY or GRAY_ALPHA */
+ {
+ /* expand background and tRNS chunks */
+ switch (png_ptr->bit_depth)
+ {
+ case 1:
+ png_ptr->background.gray *= (png_uint_16)0xff;
+ png_ptr->background.red = png_ptr->background.green
+ = png_ptr->background.blue = png_ptr->background.gray;
+ if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
+ {
+ png_ptr->trans_values.gray *= (png_uint_16)0xff;
+ png_ptr->trans_values.red = png_ptr->trans_values.green
+ = png_ptr->trans_values.blue = png_ptr->trans_values.gray;
+ }
+ break;
+ case 2:
+ png_ptr->background.gray *= (png_uint_16)0x55;
+ png_ptr->background.red = png_ptr->background.green
+ = png_ptr->background.blue = png_ptr->background.gray;
+ if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
+ {
+ png_ptr->trans_values.gray *= (png_uint_16)0x55;
+ png_ptr->trans_values.red = png_ptr->trans_values.green
+ = png_ptr->trans_values.blue = png_ptr->trans_values.gray;
+ }
+ break;
+ case 4:
+ png_ptr->background.gray *= (png_uint_16)0x11;
+ png_ptr->background.red = png_ptr->background.green
+ = png_ptr->background.blue = png_ptr->background.gray;
+ if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
+ {
+ png_ptr->trans_values.gray *= (png_uint_16)0x11;
+ png_ptr->trans_values.red = png_ptr->trans_values.green
+ = png_ptr->trans_values.blue = png_ptr->trans_values.gray;
+ }
+ break;
+ case 8:
+ case 16:
+ png_ptr->background.red = png_ptr->background.green
+ = png_ptr->background.blue = png_ptr->background.gray;
+ break;
+ }
+ }
+ else if (color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ png_ptr->background.red =
+ png_ptr->palette[png_ptr->background.index].red;
+ png_ptr->background.green =
+ png_ptr->palette[png_ptr->background.index].green;
+ png_ptr->background.blue =
+ png_ptr->palette[png_ptr->background.index].blue;
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_ALPHA)
+ {
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+ if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
+#endif
+ {
+ /* invert the alpha channel (in tRNS) unless the pixels are
+ going to be expanded, in which case leave it for later */
+ int i,istop;
+ istop=(int)png_ptr->num_trans;
+ for (i=0; i<istop; i++)
+ png_ptr->trans[i] = (png_byte)(255 - png_ptr->trans[i]);
+ }
+ }
+#endif
+
+ }
+ }
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
+ png_ptr->background_1 = png_ptr->background;
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+
+ if ((color_type == PNG_COLOR_TYPE_PALETTE && png_ptr->num_trans != 0)
+ && (fabs(png_ptr->screen_gamma * png_ptr->gamma - 1.0)
+ < PNG_GAMMA_THRESHOLD))
+ {
+ int i,k;
+ k=0;
+ for (i=0; i<png_ptr->num_trans; i++)
+ {
+ if (png_ptr->trans[i] != 0 && png_ptr->trans[i] != 0xff)
+ k=1; /* partial transparency is present */
+ }
+ if (k == 0)
+ png_ptr->transformations &= ~PNG_GAMMA;
+ }
+
+ if ((png_ptr->transformations & (PNG_GAMMA | PNG_RGB_TO_GRAY)) &&
+ png_ptr->gamma != 0.0)
+ {
+ png_build_gamma_table(png_ptr);
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->transformations & PNG_BACKGROUND)
+ {
+ if (color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ /* could skip if no transparency and
+ */
+ png_color back, back_1;
+ png_colorp palette = png_ptr->palette;
+ int num_palette = png_ptr->num_palette;
+ int i;
+ if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE)
+ {
+ back.red = png_ptr->gamma_table[png_ptr->background.red];
+ back.green = png_ptr->gamma_table[png_ptr->background.green];
+ back.blue = png_ptr->gamma_table[png_ptr->background.blue];
+
+ back_1.red = png_ptr->gamma_to_1[png_ptr->background.red];
+ back_1.green = png_ptr->gamma_to_1[png_ptr->background.green];
+ back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue];
+ }
+ else
+ {
+ double g, gs;
+
+ switch (png_ptr->background_gamma_type)
+ {
+ case PNG_BACKGROUND_GAMMA_SCREEN:
+ g = (png_ptr->screen_gamma);
+ gs = 1.0;
+ break;
+ case PNG_BACKGROUND_GAMMA_FILE:
+ g = 1.0 / (png_ptr->gamma);
+ gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+ break;
+ case PNG_BACKGROUND_GAMMA_UNIQUE:
+ g = 1.0 / (png_ptr->background_gamma);
+ gs = 1.0 / (png_ptr->background_gamma *
+ png_ptr->screen_gamma);
+ break;
+ default:
+ g = 1.0; /* back_1 */
+ gs = 1.0; /* back */
+ }
+
+ if ( fabs(gs - 1.0) < PNG_GAMMA_THRESHOLD)
+ {
+ back.red = (png_byte)png_ptr->background.red;
+ back.green = (png_byte)png_ptr->background.green;
+ back.blue = (png_byte)png_ptr->background.blue;
+ }
+ else
+ {
+ back.red = (png_byte)(pow(
+ (double)png_ptr->background.red/255, gs) * 255.0 + .5);
+ back.green = (png_byte)(pow(
+ (double)png_ptr->background.green/255, gs) * 255.0 + .5);
+ back.blue = (png_byte)(pow(
+ (double)png_ptr->background.blue/255, gs) * 255.0 + .5);
+ }
+
+ back_1.red = (png_byte)(pow(
+ (double)png_ptr->background.red/255, g) * 255.0 + .5);
+ back_1.green = (png_byte)(pow(
+ (double)png_ptr->background.green/255, g) * 255.0 + .5);
+ back_1.blue = (png_byte)(pow(
+ (double)png_ptr->background.blue/255, g) * 255.0 + .5);
+ }
+ for (i = 0; i < num_palette; i++)
+ {
+ if (i < (int)png_ptr->num_trans && png_ptr->trans[i] != 0xff)
+ {
+ if (png_ptr->trans[i] == 0)
+ {
+ palette[i] = back;
+ }
+ else /* if (png_ptr->trans[i] != 0xff) */
+ {
+ png_byte v, w;
+
+ v = png_ptr->gamma_to_1[palette[i].red];
+ png_composite(w, v, png_ptr->trans[i], back_1.red);
+ palette[i].red = png_ptr->gamma_from_1[w];
+
+ v = png_ptr->gamma_to_1[palette[i].green];
+ png_composite(w, v, png_ptr->trans[i], back_1.green);
+ palette[i].green = png_ptr->gamma_from_1[w];
+
+ v = png_ptr->gamma_to_1[palette[i].blue];
+ png_composite(w, v, png_ptr->trans[i], back_1.blue);
+ palette[i].blue = png_ptr->gamma_from_1[w];
+ }
+ }
+ else
+ {
+ palette[i].red = png_ptr->gamma_table[palette[i].red];
+ palette[i].green = png_ptr->gamma_table[palette[i].green];
+ palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+ }
+ }
+ }
+ /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN) */
+ else
+ /* color_type != PNG_COLOR_TYPE_PALETTE */
+ {
+ double m = (double)(((png_uint_32)1 << png_ptr->bit_depth) - 1);
+ double g = 1.0;
+ double gs = 1.0;
+
+ switch (png_ptr->background_gamma_type)
+ {
+ case PNG_BACKGROUND_GAMMA_SCREEN:
+ g = (png_ptr->screen_gamma);
+ gs = 1.0;
+ break;
+ case PNG_BACKGROUND_GAMMA_FILE:
+ g = 1.0 / (png_ptr->gamma);
+ gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+ break;
+ case PNG_BACKGROUND_GAMMA_UNIQUE:
+ g = 1.0 / (png_ptr->background_gamma);
+ gs = 1.0 / (png_ptr->background_gamma *
+ png_ptr->screen_gamma);
+ break;
+ }
+
+ png_ptr->background_1.gray = (png_uint_16)(pow(
+ (double)png_ptr->background.gray / m, g) * m + .5);
+ png_ptr->background.gray = (png_uint_16)(pow(
+ (double)png_ptr->background.gray / m, gs) * m + .5);
+
+ if ((png_ptr->background.red != png_ptr->background.green) ||
+ (png_ptr->background.red != png_ptr->background.blue) ||
+ (png_ptr->background.red != png_ptr->background.gray))
+ {
+ /* RGB or RGBA with color background */
+ png_ptr->background_1.red = (png_uint_16)(pow(
+ (double)png_ptr->background.red / m, g) * m + .5);
+ png_ptr->background_1.green = (png_uint_16)(pow(
+ (double)png_ptr->background.green / m, g) * m + .5);
+ png_ptr->background_1.blue = (png_uint_16)(pow(
+ (double)png_ptr->background.blue / m, g) * m + .5);
+ png_ptr->background.red = (png_uint_16)(pow(
+ (double)png_ptr->background.red / m, gs) * m + .5);
+ png_ptr->background.green = (png_uint_16)(pow(
+ (double)png_ptr->background.green / m, gs) * m + .5);
+ png_ptr->background.blue = (png_uint_16)(pow(
+ (double)png_ptr->background.blue / m, gs) * m + .5);
+ }
+ else
+ {
+ /* GRAY, GRAY ALPHA, RGB, or RGBA with gray background */
+ png_ptr->background_1.red = png_ptr->background_1.green
+ = png_ptr->background_1.blue = png_ptr->background_1.gray;
+ png_ptr->background.red = png_ptr->background.green
+ = png_ptr->background.blue = png_ptr->background.gray;
+ }
+ }
+ }
+ else
+ /* transformation does not include PNG_BACKGROUND */
+#endif /* PNG_READ_BACKGROUND_SUPPORTED */
+ if (color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ png_colorp palette = png_ptr->palette;
+ int num_palette = png_ptr->num_palette;
+ int i;
+
+ for (i = 0; i < num_palette; i++)
+ {
+ palette[i].red = png_ptr->gamma_table[palette[i].red];
+ palette[i].green = png_ptr->gamma_table[palette[i].green];
+ palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+ }
+ }
+ }
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ else
+#endif
+#endif /* PNG_READ_GAMMA_SUPPORTED && PNG_FLOATING_POINT_SUPPORTED */
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ /* No GAMMA transformation */
+ if ((png_ptr->transformations & PNG_BACKGROUND) &&
+ (color_type == PNG_COLOR_TYPE_PALETTE))
+ {
+ int i;
+ int istop = (int)png_ptr->num_trans;
+ png_color back;
+ png_colorp palette = png_ptr->palette;
+
+ back.red = (png_byte)png_ptr->background.red;
+ back.green = (png_byte)png_ptr->background.green;
+ back.blue = (png_byte)png_ptr->background.blue;
+
+ for (i = 0; i < istop; i++)
+ {
+ if (png_ptr->trans[i] == 0)
+ {
+ palette[i] = back;
+ }
+ else if (png_ptr->trans[i] != 0xff)
+ {
+ /* The png_composite() macro is defined in png.h */
+ png_composite(palette[i].red, palette[i].red,
+ png_ptr->trans[i], back.red);
+ png_composite(palette[i].green, palette[i].green,
+ png_ptr->trans[i], back.green);
+ png_composite(palette[i].blue, palette[i].blue,
+ png_ptr->trans[i], back.blue);
+ }
+ }
+ }
+#endif /* PNG_READ_BACKGROUND_SUPPORTED */
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+ if ((png_ptr->transformations & PNG_SHIFT) &&
+ (color_type == PNG_COLOR_TYPE_PALETTE))
+ {
+ png_uint_16 i;
+ png_uint_16 istop = png_ptr->num_palette;
+ int sr = 8 - png_ptr->sig_bit.red;
+ int sg = 8 - png_ptr->sig_bit.green;
+ int sb = 8 - png_ptr->sig_bit.blue;
+
+ if (sr < 0 || sr > 8)
+ sr = 0;
+ if (sg < 0 || sg > 8)
+ sg = 0;
+ if (sb < 0 || sb > 8)
+ sb = 0;
+ for (i = 0; i < istop; i++)
+ {
+ png_ptr->palette[i].red >>= sr;
+ png_ptr->palette[i].green >>= sg;
+ png_ptr->palette[i].blue >>= sb;
+ }
+ }
+#endif /* PNG_READ_SHIFT_SUPPORTED */
+ }
+#if !defined(PNG_READ_GAMMA_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) \
+ && !defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if(png_ptr)
+ return;
+#endif
+}
+
+/* Modify the info structure to reflect the transformations. The
+ * info should be updated so a PNG file could be written with it,
+ * assuming the transformations result in valid PNG data.
+ */
+void /* PRIVATE */
+png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
+{
+ png_debug(1, "in png_read_transform_info\n");
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+ if (png_ptr->transformations & PNG_EXPAND)
+ {
+ if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND_tRNS))
+ info_ptr->color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+ else
+ info_ptr->color_type = PNG_COLOR_TYPE_RGB;
+ info_ptr->bit_depth = 8;
+ info_ptr->num_trans = 0;
+ }
+ else
+ {
+ if (png_ptr->num_trans)
+ {
+ if (png_ptr->transformations & PNG_EXPAND_tRNS)
+ info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
+ else
+ info_ptr->color_type |= PNG_COLOR_MASK_COLOR;
+ }
+ if (info_ptr->bit_depth < 8)
+ info_ptr->bit_depth = 8;
+ info_ptr->num_trans = 0;
+ }
+ }
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->transformations & PNG_BACKGROUND)
+ {
+ info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA;
+ info_ptr->num_trans = 0;
+ info_ptr->background = png_ptr->background;
+ }
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (png_ptr->transformations & PNG_GAMMA)
+ {
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ info_ptr->gamma = png_ptr->gamma;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ info_ptr->int_gamma = png_ptr->int_gamma;
+#endif
+ }
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+ if ((png_ptr->transformations & PNG_16_TO_8) && (info_ptr->bit_depth == 16))
+ info_ptr->bit_depth = 8;
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+ if (png_ptr->transformations & PNG_GRAY_TO_RGB)
+ info_ptr->color_type |= PNG_COLOR_MASK_COLOR;
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & PNG_RGB_TO_GRAY)
+ info_ptr->color_type &= ~PNG_COLOR_MASK_COLOR;
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+ if (png_ptr->transformations & PNG_DITHER)
+ {
+ if (((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
+ (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) &&
+ png_ptr->palette_lookup && info_ptr->bit_depth == 8)
+ {
+ info_ptr->color_type = PNG_COLOR_TYPE_PALETTE;
+ }
+ }
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+ if ((png_ptr->transformations & PNG_PACK) && (info_ptr->bit_depth < 8))
+ info_ptr->bit_depth = 8;
+#endif
+
+ if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ info_ptr->channels = 1;
+ else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+ info_ptr->channels = 3;
+ else
+ info_ptr->channels = 1;
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+ if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)
+ info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA;
+#endif
+
+ if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+ info_ptr->channels++;
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+ /* STRIP_ALPHA and FILLER allowed: MASK_ALPHA bit stripped above */
+ if ((png_ptr->transformations & PNG_FILLER) &&
+ ((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
+ (info_ptr->color_type == PNG_COLOR_TYPE_GRAY)))
+ {
+ info_ptr->channels++;
+ /* if adding a true alpha channel not just filler */
+#if !defined(PNG_1_0_X)
+ if (png_ptr->transformations & PNG_ADD_ALPHA)
+ info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
+#endif
+ }
+#endif
+
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) && \
+defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+ if(png_ptr->transformations & PNG_USER_TRANSFORM)
+ {
+ if(info_ptr->bit_depth < png_ptr->user_transform_depth)
+ info_ptr->bit_depth = png_ptr->user_transform_depth;
+ if(info_ptr->channels < png_ptr->user_transform_channels)
+ info_ptr->channels = png_ptr->user_transform_channels;
+ }
+#endif
+
+ info_ptr->pixel_depth = (png_byte)(info_ptr->channels *
+ info_ptr->bit_depth);
+
+ info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,info_ptr->width);
+
+#if !defined(PNG_READ_EXPAND_SUPPORTED)
+ if(png_ptr)
+ return;
+#endif
+}
+
+/* Transform the row. The order of transformations is significant,
+ * and is very touchy. If you add a transformation, take care to
+ * decide how it fits in with the other transformations here.
+ */
+void /* PRIVATE */
+png_do_read_transformations(png_structp png_ptr)
+{
+ png_debug(1, "in png_do_read_transformations\n");
+ if (png_ptr->row_buf == NULL)
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char msg[50];
+
+ png_snprintf2(msg, 50,
+ "NULL row buffer for row %ld, pass %d", png_ptr->row_number,
+ png_ptr->pass);
+ png_error(png_ptr, msg);
+#else
+ png_error(png_ptr, "NULL row buffer");
+#endif
+ }
+#ifdef PNG_WARN_UNINITIALIZED_ROW
+ if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+ /* Application has failed to call either png_read_start_image()
+ * or png_read_update_info() after setting transforms that expand
+ * pixels. This check added to libpng-1.2.19 */
+#if (PNG_WARN_UNINITIALIZED_ROW==1)
+ png_error(png_ptr, "Uninitialized row");
+#else
+ png_warning(png_ptr, "Uninitialized row");
+#endif
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+ if (png_ptr->transformations & PNG_EXPAND)
+ {
+ if (png_ptr->row_info.color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ png_ptr->palette, png_ptr->trans, png_ptr->num_trans);
+ }
+ else
+ {
+ if (png_ptr->num_trans &&
+ (png_ptr->transformations & PNG_EXPAND_tRNS))
+ png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ &(png_ptr->trans_values));
+ else
+ png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ NULL);
+ }
+ }
+#endif
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+ if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)
+ png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ PNG_FLAG_FILLER_AFTER | (png_ptr->flags & PNG_FLAG_STRIP_ALPHA));
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & PNG_RGB_TO_GRAY)
+ {
+ int rgb_error =
+ png_do_rgb_to_gray(png_ptr, &(png_ptr->row_info), png_ptr->row_buf + 1);
+ if(rgb_error)
+ {
+ png_ptr->rgb_to_gray_status=1;
+ if((png_ptr->transformations & PNG_RGB_TO_GRAY) ==
+ PNG_RGB_TO_GRAY_WARN)
+ png_warning(png_ptr, "png_do_rgb_to_gray found nongray pixel");
+ if((png_ptr->transformations & PNG_RGB_TO_GRAY) ==
+ PNG_RGB_TO_GRAY_ERR)
+ png_error(png_ptr, "png_do_rgb_to_gray found nongray pixel");
+ }
+ }
+#endif
+
+/*
+From Andreas Dilger e-mail to png-implement, 26 March 1998:
+
+ In most cases, the "simple transparency" should be done prior to doing
+ gray-to-RGB, or you will have to test 3x as many bytes to check if a
+ pixel is transparent. You would also need to make sure that the
+ transparency information is upgraded to RGB.
+
+ To summarize, the current flow is:
+ - Gray + simple transparency -> compare 1 or 2 gray bytes and composite
+ with background "in place" if transparent,
+ convert to RGB if necessary
+ - Gray + alpha -> composite with gray background and remove alpha bytes,
+ convert to RGB if necessary
+
+ To support RGB backgrounds for gray images we need:
+ - Gray + simple transparency -> convert to RGB + simple transparency, compare
+ 3 or 6 bytes and composite with background
+ "in place" if transparent (3x compare/pixel
+ compared to doing composite with gray bkgrnd)
+ - Gray + alpha -> convert to RGB + alpha, composite with background and
+ remove alpha bytes (3x float operations/pixel
+ compared with composite on gray background)
+
+ Greg's change will do this. The reason it wasn't done before is for
+ performance, as this increases the per-pixel operations. If we would check
+ in advance if the background was gray or RGB, and position the gray-to-RGB
+ transform appropriately, then it would save a lot of work/time.
+ */
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+ /* if gray -> RGB, do so now only if background is non-gray; else do later
+ * for performance reasons */
+ if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
+ !(png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
+ png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if ((png_ptr->transformations & PNG_BACKGROUND) &&
+ ((png_ptr->num_trans != 0 ) ||
+ (png_ptr->color_type & PNG_COLOR_MASK_ALPHA)))
+ png_do_background(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ &(png_ptr->trans_values), &(png_ptr->background)
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ , &(png_ptr->background_1),
+ png_ptr->gamma_table, png_ptr->gamma_from_1,
+ png_ptr->gamma_to_1, png_ptr->gamma_16_table,
+ png_ptr->gamma_16_from_1, png_ptr->gamma_16_to_1,
+ png_ptr->gamma_shift
+#endif
+);
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if ((png_ptr->transformations & PNG_GAMMA) &&
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ !((png_ptr->transformations & PNG_BACKGROUND) &&
+ ((png_ptr->num_trans != 0) ||
+ (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) &&
+#endif
+ (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE))
+ png_do_gamma(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ png_ptr->gamma_table, png_ptr->gamma_16_table,
+ png_ptr->gamma_shift);
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+ if (png_ptr->transformations & PNG_16_TO_8)
+ png_do_chop(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+ if (png_ptr->transformations & PNG_DITHER)
+ {
+ png_do_dither((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1,
+ png_ptr->palette_lookup, png_ptr->dither_index);
+ if(png_ptr->row_info.rowbytes == (png_uint_32)0)
+ png_error(png_ptr, "png_do_dither returned rowbytes=0");
+ }
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_MONO)
+ png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+ if (png_ptr->transformations & PNG_SHIFT)
+ png_do_unshift(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ &(png_ptr->shift));
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACK)
+ png_do_unpack(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED)
+ if (png_ptr->transformations & PNG_BGR)
+ png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACKSWAP)
+ png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+ /* if gray -> RGB, do so now only if we did not do so above */
+ if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
+ (png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
+ png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+ if (png_ptr->transformations & PNG_FILLER)
+ png_do_read_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ (png_uint_32)png_ptr->filler, png_ptr->flags);
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_ALPHA)
+ png_do_read_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+ if (png_ptr->transformations & PNG_SWAP_ALPHA)
+ png_do_read_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_SWAP_BYTES)
+ png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+ if (png_ptr->transformations & PNG_USER_TRANSFORM)
+ {
+ if(png_ptr->read_user_transform_fn != NULL)
+ (*(png_ptr->read_user_transform_fn)) /* user read transform function */
+ (png_ptr, /* png_ptr */
+ &(png_ptr->row_info), /* row_info: */
+ /* png_uint_32 width; width of row */
+ /* png_uint_32 rowbytes; number of bytes in row */
+ /* png_byte color_type; color type of pixels */
+ /* png_byte bit_depth; bit depth of samples */
+ /* png_byte channels; number of channels (1-4) */
+ /* png_byte pixel_depth; bits per pixel (depth*channels) */
+ png_ptr->row_buf + 1); /* start of pixel data for row */
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+ if(png_ptr->user_transform_depth)
+ png_ptr->row_info.bit_depth = png_ptr->user_transform_depth;
+ if(png_ptr->user_transform_channels)
+ png_ptr->row_info.channels = png_ptr->user_transform_channels;
+#endif
+ png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
+ png_ptr->row_info.channels);
+ png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+ png_ptr->row_info.width);
+ }
+#endif
+
+}
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+/* Unpack pixels of 1, 2, or 4 bits per pixel into 1 byte per pixel,
+ * without changing the actual values. Thus, if you had a row with
+ * a bit depth of 1, you would end up with bytes that only contained
+ * the numbers 0 or 1. If you would rather they contain 0 and 255, use
+ * png_do_shift() after this.
+ */
+void /* PRIVATE */
+png_do_unpack(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_unpack\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL && row_info->bit_depth < 8)
+#else
+ if (row_info->bit_depth < 8)
+#endif
+ {
+ png_uint_32 i;
+ png_uint_32 row_width=row_info->width;
+
+ switch (row_info->bit_depth)
+ {
+ case 1:
+ {
+ png_bytep sp = row + (png_size_t)((row_width - 1) >> 3);
+ png_bytep dp = row + (png_size_t)row_width - 1;
+ png_uint_32 shift = 7 - (int)((row_width + 7) & 0x07);
+ for (i = 0; i < row_width; i++)
+ {
+ *dp = (png_byte)((*sp >> shift) & 0x01);
+ if (shift == 7)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift++;
+
+ dp--;
+ }
+ break;
+ }
+ case 2:
+ {
+
+ png_bytep sp = row + (png_size_t)((row_width - 1) >> 2);
+ png_bytep dp = row + (png_size_t)row_width - 1;
+ png_uint_32 shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
+ for (i = 0; i < row_width; i++)
+ {
+ *dp = (png_byte)((*sp >> shift) & 0x03);
+ if (shift == 6)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift += 2;
+
+ dp--;
+ }
+ break;
+ }
+ case 4:
+ {
+ png_bytep sp = row + (png_size_t)((row_width - 1) >> 1);
+ png_bytep dp = row + (png_size_t)row_width - 1;
+ png_uint_32 shift = (int)((1 - ((row_width + 1) & 0x01)) << 2);
+ for (i = 0; i < row_width; i++)
+ {
+ *dp = (png_byte)((*sp >> shift) & 0x0f);
+ if (shift == 4)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift = 4;
+
+ dp--;
+ }
+ break;
+ }
+ }
+ row_info->bit_depth = 8;
+ row_info->pixel_depth = (png_byte)(8 * row_info->channels);
+ row_info->rowbytes = row_width * row_info->channels;
+ }
+}
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+/* Reverse the effects of png_do_shift. This routine merely shifts the
+ * pixels back to their significant bits values. Thus, if you have
+ * a row of bit depth 8, but only 5 are significant, this will shift
+ * the values back to 0 through 31.
+ */
+void /* PRIVATE */
+png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
+{
+ png_debug(1, "in png_do_unshift\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL && sig_bits != NULL &&
+#endif
+ row_info->color_type != PNG_COLOR_TYPE_PALETTE)
+ {
+ int shift[4];
+ int channels = 0;
+ int c;
+ png_uint_16 value = 0;
+ png_uint_32 row_width = row_info->width;
+
+ if (row_info->color_type & PNG_COLOR_MASK_COLOR)
+ {
+ shift[channels++] = row_info->bit_depth - sig_bits->red;
+ shift[channels++] = row_info->bit_depth - sig_bits->green;
+ shift[channels++] = row_info->bit_depth - sig_bits->blue;
+ }
+ else
+ {
+ shift[channels++] = row_info->bit_depth - sig_bits->gray;
+ }
+ if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+ {
+ shift[channels++] = row_info->bit_depth - sig_bits->alpha;
+ }
+
+ for (c = 0; c < channels; c++)
+ {
+ if (shift[c] <= 0)
+ shift[c] = 0;
+ else
+ value = 1;
+ }
+
+ if (!value)
+ return;
+
+ switch (row_info->bit_depth)
+ {
+ case 2:
+ {
+ png_bytep bp;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+
+ for (bp = row, i = 0; i < istop; i++)
+ {
+ *bp >>= 1;
+ *bp++ &= 0x55;
+ }
+ break;
+ }
+ case 4:
+ {
+ png_bytep bp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+ png_byte mask = (png_byte)((((int)0xf0 >> shift[0]) & (int)0xf0) |
+ (png_byte)((int)0xf >> shift[0]));
+
+ for (i = 0; i < istop; i++)
+ {
+ *bp >>= shift[0];
+ *bp++ &= mask;
+ }
+ break;
+ }
+ case 8:
+ {
+ png_bytep bp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_width * channels;
+
+ for (i = 0; i < istop; i++)
+ {
+ *bp++ >>= shift[i%channels];
+ }
+ break;
+ }
+ case 16:
+ {
+ png_bytep bp = row;
+ png_uint_32 i;
+ png_uint_32 istop = channels * row_width;
+
+ for (i = 0; i < istop; i++)
+ {
+ value = (png_uint_16)((*bp << 8) + *(bp + 1));
+ value >>= shift[i%channels];
+ *bp++ = (png_byte)(value >> 8);
+ *bp++ = (png_byte)(value & 0xff);
+ }
+ break;
+ }
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+/* chop rows of bit depth 16 down to 8 */
+void /* PRIVATE */
+png_do_chop(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_chop\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL && row_info->bit_depth == 16)
+#else
+ if (row_info->bit_depth == 16)
+#endif
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->width * row_info->channels;
+
+ for (i = 0; i<istop; i++, sp += 2, dp++)
+ {
+#if defined(PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED)
+ /* This does a more accurate scaling of the 16-bit color
+ * value, rather than a simple low-byte truncation.
+ *
+ * What the ideal calculation should be:
+ * *dp = (((((png_uint_32)(*sp) << 8) |
+ * (png_uint_32)(*(sp + 1))) * 255 + 127) / (png_uint_32)65535L;
+ *
+ * GRR: no, I think this is what it really should be:
+ * *dp = (((((png_uint_32)(*sp) << 8) |
+ * (png_uint_32)(*(sp + 1))) + 128L) / (png_uint_32)257L;
+ *
+ * GRR: here's the exact calculation with shifts:
+ * temp = (((png_uint_32)(*sp) << 8) | (png_uint_32)(*(sp + 1))) + 128L;
+ * *dp = (temp - (temp >> 8)) >> 8;
+ *
+ * Approximate calculation with shift/add instead of multiply/divide:
+ * *dp = ((((png_uint_32)(*sp) << 8) |
+ * (png_uint_32)((int)(*(sp + 1)) - *sp)) + 128) >> 8;
+ *
+ * What we actually do to avoid extra shifting and conversion:
+ */
+
+ *dp = *sp + ((((int)(*(sp + 1)) - *sp) > 128) ? 1 : 0);
+#else
+ /* Simply discard the low order byte */
+ *dp = *sp;
+#endif
+ }
+ row_info->bit_depth = 8;
+ row_info->pixel_depth = (png_byte)(8 * row_info->channels);
+ row_info->rowbytes = row_info->width * row_info->channels;
+ }
+}
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_read_swap_alpha(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_read_swap_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL)
+#endif
+ {
+ png_uint_32 row_width = row_info->width;
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ {
+ /* This converts from RGBA to ARGB */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_byte save;
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ save = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = save;
+ }
+ }
+ /* This converts from RRGGBBAA to AARRGGBB */
+ else
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_byte save[2];
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ save[0] = *(--sp);
+ save[1] = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = save[0];
+ *(--dp) = save[1];
+ }
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ {
+ /* This converts from GA to AG */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_byte save;
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ save = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = save;
+ }
+ }
+ /* This converts from GGAA to AAGG */
+ else
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_byte save[2];
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ save[0] = *(--sp);
+ save[1] = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = save[0];
+ *(--dp) = save[1];
+ }
+ }
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_read_invert_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL)
+#endif
+ {
+ png_uint_32 row_width = row_info->width;
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ {
+ /* This inverts the alpha channel in RGBA */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = (png_byte)(255 - *(--sp));
+
+/* This does nothing:
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ We can replace it with:
+*/
+ sp-=3;
+ dp=sp;
+ }
+ }
+ /* This inverts the alpha channel in RRGGBBAA */
+ else
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = (png_byte)(255 - *(--sp));
+ *(--dp) = (png_byte)(255 - *(--sp));
+
+/* This does nothing:
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ We can replace it with:
+*/
+ sp-=6;
+ dp=sp;
+ }
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ {
+ /* This inverts the alpha channel in GA */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = (png_byte)(255 - *(--sp));
+ *(--dp) = *(--sp);
+ }
+ }
+ /* This inverts the alpha channel in GGAA */
+ else
+ {
+ png_bytep sp = row + row_info->rowbytes;
+ png_bytep dp = sp;
+ png_uint_32 i;
+
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = (png_byte)(255 - *(--sp));
+ *(--dp) = (png_byte)(255 - *(--sp));
+/*
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+*/
+ sp-=2;
+ dp=sp;
+ }
+ }
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+/* Add filler channel if we have RGB color */
+void /* PRIVATE */
+png_do_read_filler(png_row_infop row_info, png_bytep row,
+ png_uint_32 filler, png_uint_32 flags)
+{
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ png_byte hi_filler = (png_byte)((filler>>8) & 0xff);
+ png_byte lo_filler = (png_byte)(filler & 0xff);
+
+ png_debug(1, "in png_do_read_filler\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ row_info->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ if(row_info->bit_depth == 8)
+ {
+ /* This changes the data from G to GX */
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ png_bytep sp = row + (png_size_t)row_width;
+ png_bytep dp = sp + (png_size_t)row_width;
+ for (i = 1; i < row_width; i++)
+ {
+ *(--dp) = lo_filler;
+ *(--dp) = *(--sp);
+ }
+ *(--dp) = lo_filler;
+ row_info->channels = 2;
+ row_info->pixel_depth = 16;
+ row_info->rowbytes = row_width * 2;
+ }
+ /* This changes the data from G to XG */
+ else
+ {
+ png_bytep sp = row + (png_size_t)row_width;
+ png_bytep dp = sp + (png_size_t)row_width;
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = *(--sp);
+ *(--dp) = lo_filler;
+ }
+ row_info->channels = 2;
+ row_info->pixel_depth = 16;
+ row_info->rowbytes = row_width * 2;
+ }
+ }
+ else if(row_info->bit_depth == 16)
+ {
+ /* This changes the data from GG to GGXX */
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ png_bytep sp = row + (png_size_t)row_width * 2;
+ png_bytep dp = sp + (png_size_t)row_width * 2;
+ for (i = 1; i < row_width; i++)
+ {
+ *(--dp) = hi_filler;
+ *(--dp) = lo_filler;
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ }
+ *(--dp) = hi_filler;
+ *(--dp) = lo_filler;
+ row_info->channels = 2;
+ row_info->pixel_depth = 32;
+ row_info->rowbytes = row_width * 4;
+ }
+ /* This changes the data from GG to XXGG */
+ else
+ {
+ png_bytep sp = row + (png_size_t)row_width * 2;
+ png_bytep dp = sp + (png_size_t)row_width * 2;
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = hi_filler;
+ *(--dp) = lo_filler;
+ }
+ row_info->channels = 2;
+ row_info->pixel_depth = 32;
+ row_info->rowbytes = row_width * 4;
+ }
+ }
+ } /* COLOR_TYPE == GRAY */
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ if(row_info->bit_depth == 8)
+ {
+ /* This changes the data from RGB to RGBX */
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ png_bytep sp = row + (png_size_t)row_width * 3;
+ png_bytep dp = sp + (png_size_t)row_width;
+ for (i = 1; i < row_width; i++)
+ {
+ *(--dp) = lo_filler;
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ }
+ *(--dp) = lo_filler;
+ row_info->channels = 4;
+ row_info->pixel_depth = 32;
+ row_info->rowbytes = row_width * 4;
+ }
+ /* This changes the data from RGB to XRGB */
+ else
+ {
+ png_bytep sp = row + (png_size_t)row_width * 3;
+ png_bytep dp = sp + (png_size_t)row_width;
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = lo_filler;
+ }
+ row_info->channels = 4;
+ row_info->pixel_depth = 32;
+ row_info->rowbytes = row_width * 4;
+ }
+ }
+ else if(row_info->bit_depth == 16)
+ {
+ /* This changes the data from RRGGBB to RRGGBBXX */
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ png_bytep sp = row + (png_size_t)row_width * 6;
+ png_bytep dp = sp + (png_size_t)row_width * 2;
+ for (i = 1; i < row_width; i++)
+ {
+ *(--dp) = hi_filler;
+ *(--dp) = lo_filler;
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ }
+ *(--dp) = hi_filler;
+ *(--dp) = lo_filler;
+ row_info->channels = 4;
+ row_info->pixel_depth = 64;
+ row_info->rowbytes = row_width * 8;
+ }
+ /* This changes the data from RRGGBB to XXRRGGBB */
+ else
+ {
+ png_bytep sp = row + (png_size_t)row_width * 6;
+ png_bytep dp = sp + (png_size_t)row_width * 2;
+ for (i = 0; i < row_width; i++)
+ {
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = *(--sp);
+ *(--dp) = hi_filler;
+ *(--dp) = lo_filler;
+ }
+ row_info->channels = 4;
+ row_info->pixel_depth = 64;
+ row_info->rowbytes = row_width * 8;
+ }
+ }
+ } /* COLOR_TYPE == RGB */
+}
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+/* expand grayscale files to RGB, with or without alpha */
+void /* PRIVATE */
+png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
+{
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ png_debug(1, "in png_do_gray_to_rgb\n");
+ if (row_info->bit_depth >= 8 &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ !(row_info->color_type & PNG_COLOR_MASK_COLOR))
+ {
+ if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp = row + (png_size_t)row_width - 1;
+ png_bytep dp = sp + (png_size_t)row_width * 2;
+ for (i = 0; i < row_width; i++)
+ {
+ *(dp--) = *sp;
+ *(dp--) = *sp;
+ *(dp--) = *(sp--);
+ }
+ }
+ else
+ {
+ png_bytep sp = row + (png_size_t)row_width * 2 - 1;
+ png_bytep dp = sp + (png_size_t)row_width * 4;
+ for (i = 0; i < row_width; i++)
+ {
+ *(dp--) = *sp;
+ *(dp--) = *(sp - 1);
+ *(dp--) = *sp;
+ *(dp--) = *(sp - 1);
+ *(dp--) = *(sp--);
+ *(dp--) = *(sp--);
+ }
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp = row + (png_size_t)row_width * 2 - 1;
+ png_bytep dp = sp + (png_size_t)row_width * 2;
+ for (i = 0; i < row_width; i++)
+ {
+ *(dp--) = *(sp--);
+ *(dp--) = *sp;
+ *(dp--) = *sp;
+ *(dp--) = *(sp--);
+ }
+ }
+ else
+ {
+ png_bytep sp = row + (png_size_t)row_width * 4 - 1;
+ png_bytep dp = sp + (png_size_t)row_width * 4;
+ for (i = 0; i < row_width; i++)
+ {
+ *(dp--) = *(sp--);
+ *(dp--) = *(sp--);
+ *(dp--) = *sp;
+ *(dp--) = *(sp - 1);
+ *(dp--) = *sp;
+ *(dp--) = *(sp - 1);
+ *(dp--) = *(sp--);
+ *(dp--) = *(sp--);
+ }
+ }
+ }
+ row_info->channels += (png_byte)2;
+ row_info->color_type |= PNG_COLOR_MASK_COLOR;
+ row_info->pixel_depth = (png_byte)(row_info->channels *
+ row_info->bit_depth);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+ }
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+/* reduce RGB files to grayscale, with or without alpha
+ * using the equation given in Poynton's ColorFAQ at
+ * <http://www.inforamp.net/~poynton/>
+ * Copyright (c) 1998-01-04 Charles Poynton poynton at inforamp.net
+ *
+ * Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
+ *
+ * We approximate this with
+ *
+ * Y = 0.21268 * R + 0.7151 * G + 0.07217 * B
+ *
+ * which can be expressed with integers as
+ *
+ * Y = (6969 * R + 23434 * G + 2365 * B)/32768
+ *
+ * The calculation is to be done in a linear colorspace.
+ *
+ * Other integer coefficents can be used via png_set_rgb_to_gray().
+ */
+int /* PRIVATE */
+png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
+
+{
+ png_uint_32 i;
+
+ png_uint_32 row_width = row_info->width;
+ int rgb_error = 0;
+
+ png_debug(1, "in png_do_rgb_to_gray\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ (row_info->color_type & PNG_COLOR_MASK_COLOR))
+ {
+ png_uint_32 rc = png_ptr->rgb_to_gray_red_coeff;
+ png_uint_32 gc = png_ptr->rgb_to_gray_green_coeff;
+ png_uint_32 bc = png_ptr->rgb_to_gray_blue_coeff;
+
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ if (row_info->bit_depth == 8)
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL)
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+
+ for (i = 0; i < row_width; i++)
+ {
+ png_byte red = png_ptr->gamma_to_1[*(sp++)];
+ png_byte green = png_ptr->gamma_to_1[*(sp++)];
+ png_byte blue = png_ptr->gamma_to_1[*(sp++)];
+ if(red != green || red != blue)
+ {
+ rgb_error |= 1;
+ *(dp++) = png_ptr->gamma_from_1[
+ (rc*red+gc*green+bc*blue)>>15];
+ }
+ else
+ *(dp++) = *(sp-1);
+ }
+ }
+ else
+#endif
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_byte red = *(sp++);
+ png_byte green = *(sp++);
+ png_byte blue = *(sp++);
+ if(red != green || red != blue)
+ {
+ rgb_error |= 1;
+ *(dp++) = (png_byte)((rc*red+gc*green+bc*blue)>>15);
+ }
+ else
+ *(dp++) = *(sp-1);
+ }
+ }
+ }
+
+ else /* RGB bit_depth == 16 */
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->gamma_16_to_1 != NULL &&
+ png_ptr->gamma_16_from_1 != NULL)
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 red, green, blue, w;
+
+ red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+ green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+ blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+
+ if(red == green && red == blue)
+ w = red;
+ else
+ {
+ png_uint_16 red_1 = png_ptr->gamma_16_to_1[(red&0xff) >>
+ png_ptr->gamma_shift][red>>8];
+ png_uint_16 green_1 = png_ptr->gamma_16_to_1[(green&0xff) >>
+ png_ptr->gamma_shift][green>>8];
+ png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >>
+ png_ptr->gamma_shift][blue>>8];
+ png_uint_16 gray16 = (png_uint_16)((rc*red_1 + gc*green_1
+ + bc*blue_1)>>15);
+ w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
+ png_ptr->gamma_shift][gray16 >> 8];
+ rgb_error |= 1;
+ }
+
+ *(dp++) = (png_byte)((w>>8) & 0xff);
+ *(dp++) = (png_byte)(w & 0xff);
+ }
+ }
+ else
+#endif
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 red, green, blue, gray16;
+
+ red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+ green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+ blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+
+ if(red != green || red != blue)
+ rgb_error |= 1;
+ gray16 = (png_uint_16)((rc*red + gc*green + bc*blue)>>15);
+ *(dp++) = (png_byte)((gray16>>8) & 0xff);
+ *(dp++) = (png_byte)(gray16 & 0xff);
+ }
+ }
+ }
+ }
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ {
+ if (row_info->bit_depth == 8)
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL)
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_byte red = png_ptr->gamma_to_1[*(sp++)];
+ png_byte green = png_ptr->gamma_to_1[*(sp++)];
+ png_byte blue = png_ptr->gamma_to_1[*(sp++)];
+ if(red != green || red != blue)
+ rgb_error |= 1;
+ *(dp++) = png_ptr->gamma_from_1
+ [(rc*red + gc*green + bc*blue)>>15];
+ *(dp++) = *(sp++); /* alpha */
+ }
+ }
+ else
+#endif
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_byte red = *(sp++);
+ png_byte green = *(sp++);
+ png_byte blue = *(sp++);
+ if(red != green || red != blue)
+ rgb_error |= 1;
+ *(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15);
+ *(dp++) = *(sp++); /* alpha */
+ }
+ }
+ }
+ else /* RGBA bit_depth == 16 */
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->gamma_16_to_1 != NULL &&
+ png_ptr->gamma_16_from_1 != NULL)
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 red, green, blue, w;
+
+ red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+ green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+ blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+
+ if(red == green && red == blue)
+ w = red;
+ else
+ {
+ png_uint_16 red_1 = png_ptr->gamma_16_to_1[(red&0xff) >>
+ png_ptr->gamma_shift][red>>8];
+ png_uint_16 green_1 = png_ptr->gamma_16_to_1[(green&0xff) >>
+ png_ptr->gamma_shift][green>>8];
+ png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >>
+ png_ptr->gamma_shift][blue>>8];
+ png_uint_16 gray16 = (png_uint_16)((rc * red_1
+ + gc * green_1 + bc * blue_1)>>15);
+ w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
+ png_ptr->gamma_shift][gray16 >> 8];
+ rgb_error |= 1;
+ }
+
+ *(dp++) = (png_byte)((w>>8) & 0xff);
+ *(dp++) = (png_byte)(w & 0xff);
+ *(dp++) = *(sp++); /* alpha */
+ *(dp++) = *(sp++);
+ }
+ }
+ else
+#endif
+ {
+ png_bytep sp = row;
+ png_bytep dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 red, green, blue, gray16;
+ red = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+ green = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+ blue = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+ if(red != green || red != blue)
+ rgb_error |= 1;
+ gray16 = (png_uint_16)((rc*red + gc*green + bc*blue)>>15);
+ *(dp++) = (png_byte)((gray16>>8) & 0xff);
+ *(dp++) = (png_byte)(gray16 & 0xff);
+ *(dp++) = *(sp++); /* alpha */
+ *(dp++) = *(sp++);
+ }
+ }
+ }
+ }
+ row_info->channels -= (png_byte)2;
+ row_info->color_type &= ~PNG_COLOR_MASK_COLOR;
+ row_info->pixel_depth = (png_byte)(row_info->channels *
+ row_info->bit_depth);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+ }
+ return rgb_error;
+}
+#endif
+
+/* Build a grayscale palette. Palette is assumed to be 1 << bit_depth
+ * large of png_color. This lets grayscale images be treated as
+ * paletted. Most useful for gamma correction and simplification
+ * of code.
+ */
+void PNGAPI
+png_build_grayscale_palette(int bit_depth, png_colorp palette)
+{
+ int num_palette;
+ int color_inc;
+ int i;
+ int v;
+
+ png_debug(1, "in png_do_build_grayscale_palette\n");
+ if (palette == NULL)
+ return;
+
+ switch (bit_depth)
+ {
+ case 1:
+ num_palette = 2;
+ color_inc = 0xff;
+ break;
+ case 2:
+ num_palette = 4;
+ color_inc = 0x55;
+ break;
+ case 4:
+ num_palette = 16;
+ color_inc = 0x11;
+ break;
+ case 8:
+ num_palette = 256;
+ color_inc = 1;
+ break;
+ default:
+ num_palette = 0;
+ color_inc = 0;
+ break;
+ }
+
+ for (i = 0, v = 0; i < num_palette; i++, v += color_inc)
+ {
+ palette[i].red = (png_byte)v;
+ palette[i].green = (png_byte)v;
+ palette[i].blue = (png_byte)v;
+ }
+}
+
+/* This function is currently unused. Do we really need it? */
+#if defined(PNG_READ_DITHER_SUPPORTED) && defined(PNG_CORRECT_PALETTE_SUPPORTED)
+void /* PRIVATE */
+png_correct_palette(png_structp png_ptr, png_colorp palette,
+ int num_palette)
+{
+ png_debug(1, "in png_correct_palette\n");
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
+ defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+ if (png_ptr->transformations & (PNG_GAMMA | PNG_BACKGROUND))
+ {
+ png_color back, back_1;
+
+ if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE)
+ {
+ back.red = png_ptr->gamma_table[png_ptr->background.red];
+ back.green = png_ptr->gamma_table[png_ptr->background.green];
+ back.blue = png_ptr->gamma_table[png_ptr->background.blue];
+
+ back_1.red = png_ptr->gamma_to_1[png_ptr->background.red];
+ back_1.green = png_ptr->gamma_to_1[png_ptr->background.green];
+ back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue];
+ }
+ else
+ {
+ double g;
+
+ g = 1.0 / (png_ptr->background_gamma * png_ptr->screen_gamma);
+
+ if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_SCREEN ||
+ fabs(g - 1.0) < PNG_GAMMA_THRESHOLD)
+ {
+ back.red = png_ptr->background.red;
+ back.green = png_ptr->background.green;
+ back.blue = png_ptr->background.blue;
+ }
+ else
+ {
+ back.red =
+ (png_byte)(pow((double)png_ptr->background.red/255, g) *
+ 255.0 + 0.5);
+ back.green =
+ (png_byte)(pow((double)png_ptr->background.green/255, g) *
+ 255.0 + 0.5);
+ back.blue =
+ (png_byte)(pow((double)png_ptr->background.blue/255, g) *
+ 255.0 + 0.5);
+ }
+
+ g = 1.0 / png_ptr->background_gamma;
+
+ back_1.red =
+ (png_byte)(pow((double)png_ptr->background.red/255, g) *
+ 255.0 + 0.5);
+ back_1.green =
+ (png_byte)(pow((double)png_ptr->background.green/255, g) *
+ 255.0 + 0.5);
+ back_1.blue =
+ (png_byte)(pow((double)png_ptr->background.blue/255, g) *
+ 255.0 + 0.5);
+ }
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ png_uint_32 i;
+
+ for (i = 0; i < (png_uint_32)num_palette; i++)
+ {
+ if (i < png_ptr->num_trans && png_ptr->trans[i] == 0)
+ {
+ palette[i] = back;
+ }
+ else if (i < png_ptr->num_trans && png_ptr->trans[i] != 0xff)
+ {
+ png_byte v, w;
+
+ v = png_ptr->gamma_to_1[png_ptr->palette[i].red];
+ png_composite(w, v, png_ptr->trans[i], back_1.red);
+ palette[i].red = png_ptr->gamma_from_1[w];
+
+ v = png_ptr->gamma_to_1[png_ptr->palette[i].green];
+ png_composite(w, v, png_ptr->trans[i], back_1.green);
+ palette[i].green = png_ptr->gamma_from_1[w];
+
+ v = png_ptr->gamma_to_1[png_ptr->palette[i].blue];
+ png_composite(w, v, png_ptr->trans[i], back_1.blue);
+ palette[i].blue = png_ptr->gamma_from_1[w];
+ }
+ else
+ {
+ palette[i].red = png_ptr->gamma_table[palette[i].red];
+ palette[i].green = png_ptr->gamma_table[palette[i].green];
+ palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+ }
+ }
+ }
+ else
+ {
+ int i;
+
+ for (i = 0; i < num_palette; i++)
+ {
+ if (palette[i].red == (png_byte)png_ptr->trans_values.gray)
+ {
+ palette[i] = back;
+ }
+ else
+ {
+ palette[i].red = png_ptr->gamma_table[palette[i].red];
+ palette[i].green = png_ptr->gamma_table[palette[i].green];
+ palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+ }
+ }
+ }
+ }
+ else
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (png_ptr->transformations & PNG_GAMMA)
+ {
+ int i;
+
+ for (i = 0; i < num_palette; i++)
+ {
+ palette[i].red = png_ptr->gamma_table[palette[i].red];
+ palette[i].green = png_ptr->gamma_table[palette[i].green];
+ palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+ }
+ }
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ else
+#endif
+#endif
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->transformations & PNG_BACKGROUND)
+ {
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ png_color back;
+
+ back.red = (png_byte)png_ptr->background.red;
+ back.green = (png_byte)png_ptr->background.green;
+ back.blue = (png_byte)png_ptr->background.blue;
+
+ for (i = 0; i < (int)png_ptr->num_trans; i++)
+ {
+ if (png_ptr->trans[i] == 0)
+ {
+ palette[i].red = back.red;
+ palette[i].green = back.green;
+ palette[i].blue = back.blue;
+ }
+ else if (png_ptr->trans[i] != 0xff)
+ {
+ png_composite(palette[i].red, png_ptr->palette[i].red,
+ png_ptr->trans[i], back.red);
+ png_composite(palette[i].green, png_ptr->palette[i].green,
+ png_ptr->trans[i], back.green);
+ png_composite(palette[i].blue, png_ptr->palette[i].blue,
+ png_ptr->trans[i], back.blue);
+ }
+ }
+ }
+ else /* assume grayscale palette (what else could it be?) */
+ {
+ int i;
+
+ for (i = 0; i < num_palette; i++)
+ {
+ if (i == (png_byte)png_ptr->trans_values.gray)
+ {
+ palette[i].red = (png_byte)png_ptr->background.red;
+ palette[i].green = (png_byte)png_ptr->background.green;
+ palette[i].blue = (png_byte)png_ptr->background.blue;
+ }
+ }
+ }
+ }
+#endif
+}
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+/* Replace any alpha or transparency with the supplied background color.
+ * "background" is already in the screen gamma, while "background_1" is
+ * at a gamma of 1.0. Paletted files have already been taken care of.
+ */
+void /* PRIVATE */
+png_do_background(png_row_infop row_info, png_bytep row,
+ png_color_16p trans_values, png_color_16p background
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ , png_color_16p background_1,
+ png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
+ png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
+ png_uint_16pp gamma_16_to_1, int gamma_shift
+#endif
+ )
+{
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width=row_info->width;
+ int shift;
+
+ png_debug(1, "in png_do_background\n");
+ if (background != NULL &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ (!(row_info->color_type & PNG_COLOR_MASK_ALPHA) ||
+ (row_info->color_type != PNG_COLOR_TYPE_PALETTE && trans_values)))
+ {
+ switch (row_info->color_type)
+ {
+ case PNG_COLOR_TYPE_GRAY:
+ {
+ switch (row_info->bit_depth)
+ {
+ case 1:
+ {
+ sp = row;
+ shift = 7;
+ for (i = 0; i < row_width; i++)
+ {
+ if ((png_uint_16)((*sp >> shift) & 0x01)
+ == trans_values->gray)
+ {
+ *sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
+ *sp |= (png_byte)(background->gray << shift);
+ }
+ if (!shift)
+ {
+ shift = 7;
+ sp++;
+ }
+ else
+ shift--;
+ }
+ break;
+ }
+ case 2:
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_table != NULL)
+ {
+ sp = row;
+ shift = 6;
+ for (i = 0; i < row_width; i++)
+ {
+ if ((png_uint_16)((*sp >> shift) & 0x03)
+ == trans_values->gray)
+ {
+ *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+ *sp |= (png_byte)(background->gray << shift);
+ }
+ else
+ {
+ png_byte p = (png_byte)((*sp >> shift) & 0x03);
+ png_byte g = (png_byte)((gamma_table [p | (p << 2) |
+ (p << 4) | (p << 6)] >> 6) & 0x03);
+ *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+ *sp |= (png_byte)(g << shift);
+ }
+ if (!shift)
+ {
+ shift = 6;
+ sp++;
+ }
+ else
+ shift -= 2;
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ shift = 6;
+ for (i = 0; i < row_width; i++)
+ {
+ if ((png_uint_16)((*sp >> shift) & 0x03)
+ == trans_values->gray)
+ {
+ *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+ *sp |= (png_byte)(background->gray << shift);
+ }
+ if (!shift)
+ {
+ shift = 6;
+ sp++;
+ }
+ else
+ shift -= 2;
+ }
+ }
+ break;
+ }
+ case 4:
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_table != NULL)
+ {
+ sp = row;
+ shift = 4;
+ for (i = 0; i < row_width; i++)
+ {
+ if ((png_uint_16)((*sp >> shift) & 0x0f)
+ == trans_values->gray)
+ {
+ *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+ *sp |= (png_byte)(background->gray << shift);
+ }
+ else
+ {
+ png_byte p = (png_byte)((*sp >> shift) & 0x0f);
+ png_byte g = (png_byte)((gamma_table[p |
+ (p << 4)] >> 4) & 0x0f);
+ *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+ *sp |= (png_byte)(g << shift);
+ }
+ if (!shift)
+ {
+ shift = 4;
+ sp++;
+ }
+ else
+ shift -= 4;
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ shift = 4;
+ for (i = 0; i < row_width; i++)
+ {
+ if ((png_uint_16)((*sp >> shift) & 0x0f)
+ == trans_values->gray)
+ {
+ *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+ *sp |= (png_byte)(background->gray << shift);
+ }
+ if (!shift)
+ {
+ shift = 4;
+ sp++;
+ }
+ else
+ shift -= 4;
+ }
+ }
+ break;
+ }
+ case 8:
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_table != NULL)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp++)
+ {
+ if (*sp == trans_values->gray)
+ {
+ *sp = (png_byte)background->gray;
+ }
+ else
+ {
+ *sp = gamma_table[*sp];
+ }
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp++)
+ {
+ if (*sp == trans_values->gray)
+ {
+ *sp = (png_byte)background->gray;
+ }
+ }
+ }
+ break;
+ }
+ case 16:
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_16 != NULL)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp += 2)
+ {
+ png_uint_16 v;
+
+ v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+ if (v == trans_values->gray)
+ {
+ /* background is already in screen gamma */
+ *sp = (png_byte)((background->gray >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(background->gray & 0xff);
+ }
+ else
+ {
+ v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ }
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp += 2)
+ {
+ png_uint_16 v;
+
+ v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+ if (v == trans_values->gray)
+ {
+ *sp = (png_byte)((background->gray >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(background->gray & 0xff);
+ }
+ }
+ }
+ break;
+ }
+ }
+ break;
+ }
+ case PNG_COLOR_TYPE_RGB:
+ {
+ if (row_info->bit_depth == 8)
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_table != NULL)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp += 3)
+ {
+ if (*sp == trans_values->red &&
+ *(sp + 1) == trans_values->green &&
+ *(sp + 2) == trans_values->blue)
+ {
+ *sp = (png_byte)background->red;
+ *(sp + 1) = (png_byte)background->green;
+ *(sp + 2) = (png_byte)background->blue;
+ }
+ else
+ {
+ *sp = gamma_table[*sp];
+ *(sp + 1) = gamma_table[*(sp + 1)];
+ *(sp + 2) = gamma_table[*(sp + 2)];
+ }
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp += 3)
+ {
+ if (*sp == trans_values->red &&
+ *(sp + 1) == trans_values->green &&
+ *(sp + 2) == trans_values->blue)
+ {
+ *sp = (png_byte)background->red;
+ *(sp + 1) = (png_byte)background->green;
+ *(sp + 2) = (png_byte)background->blue;
+ }
+ }
+ }
+ }
+ else /* if (row_info->bit_depth == 16) */
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_16 != NULL)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp += 6)
+ {
+ png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+ png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+ png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5));
+ if (r == trans_values->red && g == trans_values->green &&
+ b == trans_values->blue)
+ {
+ /* background is already in screen gamma */
+ *sp = (png_byte)((background->red >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(background->red & 0xff);
+ *(sp + 2) = (png_byte)((background->green >> 8) & 0xff);
+ *(sp + 3) = (png_byte)(background->green & 0xff);
+ *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+ *(sp + 5) = (png_byte)(background->blue & 0xff);
+ }
+ else
+ {
+ png_uint_16 v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)];
+ *(sp + 2) = (png_byte)((v >> 8) & 0xff);
+ *(sp + 3) = (png_byte)(v & 0xff);
+ v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)];
+ *(sp + 4) = (png_byte)((v >> 8) & 0xff);
+ *(sp + 5) = (png_byte)(v & 0xff);
+ }
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp += 6)
+ {
+ png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp+1));
+ png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+ png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5));
+
+ if (r == trans_values->red && g == trans_values->green &&
+ b == trans_values->blue)
+ {
+ *sp = (png_byte)((background->red >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(background->red & 0xff);
+ *(sp + 2) = (png_byte)((background->green >> 8) & 0xff);
+ *(sp + 3) = (png_byte)(background->green & 0xff);
+ *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+ *(sp + 5) = (png_byte)(background->blue & 0xff);
+ }
+ }
+ }
+ }
+ break;
+ }
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ {
+ if (row_info->bit_depth == 8)
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_to_1 != NULL && gamma_from_1 != NULL &&
+ gamma_table != NULL)
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 2, dp++)
+ {
+ png_uint_16 a = *(sp + 1);
+
+ if (a == 0xff)
+ {
+ *dp = gamma_table[*sp];
+ }
+ else if (a == 0)
+ {
+ /* background is already in screen gamma */
+ *dp = (png_byte)background->gray;
+ }
+ else
+ {
+ png_byte v, w;
+
+ v = gamma_to_1[*sp];
+ png_composite(w, v, a, background_1->gray);
+ *dp = gamma_from_1[w];
+ }
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 2, dp++)
+ {
+ png_byte a = *(sp + 1);
+
+ if (a == 0xff)
+ {
+ *dp = *sp;
+ }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ else if (a == 0)
+ {
+ *dp = (png_byte)background->gray;
+ }
+ else
+ {
+ png_composite(*dp, *sp, a, background_1->gray);
+ }
+#else
+ *dp = (png_byte)background->gray;
+#endif
+ }
+ }
+ }
+ else /* if (png_ptr->bit_depth == 16) */
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_16 != NULL && gamma_16_from_1 != NULL &&
+ gamma_16_to_1 != NULL)
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 4, dp += 2)
+ {
+ png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+
+ if (a == (png_uint_16)0xffff)
+ {
+ png_uint_16 v;
+
+ v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+ *dp = (png_byte)((v >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(v & 0xff);
+ }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ else if (a == 0)
+#else
+ else
+#endif
+ {
+ /* background is already in screen gamma */
+ *dp = (png_byte)((background->gray >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(background->gray & 0xff);
+ }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ else
+ {
+ png_uint_16 g, v, w;
+
+ g = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp];
+ png_composite_16(v, g, a, background_1->gray);
+ w = gamma_16_from_1[(v&0xff) >> gamma_shift][v >> 8];
+ *dp = (png_byte)((w >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(w & 0xff);
+ }
+#endif
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 4, dp += 2)
+ {
+ png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+ if (a == (png_uint_16)0xffff)
+ {
+ png_memcpy(dp, sp, 2);
+ }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ else if (a == 0)
+#else
+ else
+#endif
+ {
+ *dp = (png_byte)((background->gray >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(background->gray & 0xff);
+ }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ else
+ {
+ png_uint_16 g, v;
+
+ g = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+ png_composite_16(v, g, a, background_1->gray);
+ *dp = (png_byte)((v >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(v & 0xff);
+ }
+#endif
+ }
+ }
+ }
+ break;
+ }
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ {
+ if (row_info->bit_depth == 8)
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_to_1 != NULL && gamma_from_1 != NULL &&
+ gamma_table != NULL)
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 4, dp += 3)
+ {
+ png_byte a = *(sp + 3);
+
+ if (a == 0xff)
+ {
+ *dp = gamma_table[*sp];
+ *(dp + 1) = gamma_table[*(sp + 1)];
+ *(dp + 2) = gamma_table[*(sp + 2)];
+ }
+ else if (a == 0)
+ {
+ /* background is already in screen gamma */
+ *dp = (png_byte)background->red;
+ *(dp + 1) = (png_byte)background->green;
+ *(dp + 2) = (png_byte)background->blue;
+ }
+ else
+ {
+ png_byte v, w;
+
+ v = gamma_to_1[*sp];
+ png_composite(w, v, a, background_1->red);
+ *dp = gamma_from_1[w];
+ v = gamma_to_1[*(sp + 1)];
+ png_composite(w, v, a, background_1->green);
+ *(dp + 1) = gamma_from_1[w];
+ v = gamma_to_1[*(sp + 2)];
+ png_composite(w, v, a, background_1->blue);
+ *(dp + 2) = gamma_from_1[w];
+ }
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 4, dp += 3)
+ {
+ png_byte a = *(sp + 3);
+
+ if (a == 0xff)
+ {
+ *dp = *sp;
+ *(dp + 1) = *(sp + 1);
+ *(dp + 2) = *(sp + 2);
+ }
+ else if (a == 0)
+ {
+ *dp = (png_byte)background->red;
+ *(dp + 1) = (png_byte)background->green;
+ *(dp + 2) = (png_byte)background->blue;
+ }
+ else
+ {
+ png_composite(*dp, *sp, a, background->red);
+ png_composite(*(dp + 1), *(sp + 1), a,
+ background->green);
+ png_composite(*(dp + 2), *(sp + 2), a,
+ background->blue);
+ }
+ }
+ }
+ }
+ else /* if (row_info->bit_depth == 16) */
+ {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (gamma_16 != NULL && gamma_16_from_1 != NULL &&
+ gamma_16_to_1 != NULL)
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 8, dp += 6)
+ {
+ png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6))
+ << 8) + (png_uint_16)(*(sp + 7)));
+ if (a == (png_uint_16)0xffff)
+ {
+ png_uint_16 v;
+
+ v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+ *dp = (png_byte)((v >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(v & 0xff);
+ v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)];
+ *(dp + 2) = (png_byte)((v >> 8) & 0xff);
+ *(dp + 3) = (png_byte)(v & 0xff);
+ v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)];
+ *(dp + 4) = (png_byte)((v >> 8) & 0xff);
+ *(dp + 5) = (png_byte)(v & 0xff);
+ }
+ else if (a == 0)
+ {
+ /* background is already in screen gamma */
+ *dp = (png_byte)((background->red >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(background->red & 0xff);
+ *(dp + 2) = (png_byte)((background->green >> 8) & 0xff);
+ *(dp + 3) = (png_byte)(background->green & 0xff);
+ *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+ *(dp + 5) = (png_byte)(background->blue & 0xff);
+ }
+ else
+ {
+ png_uint_16 v, w, x;
+
+ v = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp];
+ png_composite_16(w, v, a, background_1->red);
+ x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8];
+ *dp = (png_byte)((x >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(x & 0xff);
+ v = gamma_16_to_1[*(sp + 3) >> gamma_shift][*(sp + 2)];
+ png_composite_16(w, v, a, background_1->green);
+ x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8];
+ *(dp + 2) = (png_byte)((x >> 8) & 0xff);
+ *(dp + 3) = (png_byte)(x & 0xff);
+ v = gamma_16_to_1[*(sp + 5) >> gamma_shift][*(sp + 4)];
+ png_composite_16(w, v, a, background_1->blue);
+ x = gamma_16_from_1[(w & 0xff) >> gamma_shift][w >> 8];
+ *(dp + 4) = (png_byte)((x >> 8) & 0xff);
+ *(dp + 5) = (png_byte)(x & 0xff);
+ }
+ }
+ }
+ else
+#endif
+ {
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++, sp += 8, dp += 6)
+ {
+ png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6))
+ << 8) + (png_uint_16)(*(sp + 7)));
+ if (a == (png_uint_16)0xffff)
+ {
+ png_memcpy(dp, sp, 6);
+ }
+ else if (a == 0)
+ {
+ *dp = (png_byte)((background->red >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(background->red & 0xff);
+ *(dp + 2) = (png_byte)((background->green >> 8) & 0xff);
+ *(dp + 3) = (png_byte)(background->green & 0xff);
+ *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+ *(dp + 5) = (png_byte)(background->blue & 0xff);
+ }
+ else
+ {
+ png_uint_16 v;
+
+ png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+ png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8)
+ + *(sp + 3));
+ png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8)
+ + *(sp + 5));
+
+ png_composite_16(v, r, a, background->red);
+ *dp = (png_byte)((v >> 8) & 0xff);
+ *(dp + 1) = (png_byte)(v & 0xff);
+ png_composite_16(v, g, a, background->green);
+ *(dp + 2) = (png_byte)((v >> 8) & 0xff);
+ *(dp + 3) = (png_byte)(v & 0xff);
+ png_composite_16(v, b, a, background->blue);
+ *(dp + 4) = (png_byte)((v >> 8) & 0xff);
+ *(dp + 5) = (png_byte)(v & 0xff);
+ }
+ }
+ }
+ }
+ break;
+ }
+ }
+
+ if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+ {
+ row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
+ row_info->channels--;
+ row_info->pixel_depth = (png_byte)(row_info->channels *
+ row_info->bit_depth);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+/* Gamma correct the image, avoiding the alpha channel. Make sure
+ * you do this after you deal with the transparency issue on grayscale
+ * or RGB images. If your bit depth is 8, use gamma_table, if it
+ * is 16, use gamma_16_table and gamma_shift. Build these with
+ * build_gamma_table().
+ */
+void /* PRIVATE */
+png_do_gamma(png_row_infop row_info, png_bytep row,
+ png_bytep gamma_table, png_uint_16pp gamma_16_table,
+ int gamma_shift)
+{
+ png_bytep sp;
+ png_uint_32 i;
+ png_uint_32 row_width=row_info->width;
+
+ png_debug(1, "in png_do_gamma\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ ((row_info->bit_depth <= 8 && gamma_table != NULL) ||
+ (row_info->bit_depth == 16 && gamma_16_table != NULL)))
+ {
+ switch (row_info->color_type)
+ {
+ case PNG_COLOR_TYPE_RGB:
+ {
+ if (row_info->bit_depth == 8)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ *sp = gamma_table[*sp];
+ sp++;
+ *sp = gamma_table[*sp];
+ sp++;
+ *sp = gamma_table[*sp];
+ sp++;
+ }
+ }
+ else /* if (row_info->bit_depth == 16) */
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 v;
+
+ v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 2;
+ v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 2;
+ v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 2;
+ }
+ }
+ break;
+ }
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ {
+ if (row_info->bit_depth == 8)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ *sp = gamma_table[*sp];
+ sp++;
+ *sp = gamma_table[*sp];
+ sp++;
+ *sp = gamma_table[*sp];
+ sp++;
+ sp++;
+ }
+ }
+ else /* if (row_info->bit_depth == 16) */
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 2;
+ v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 2;
+ v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 4;
+ }
+ }
+ break;
+ }
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ {
+ if (row_info->bit_depth == 8)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ *sp = gamma_table[*sp];
+ sp += 2;
+ }
+ }
+ else /* if (row_info->bit_depth == 16) */
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 4;
+ }
+ }
+ break;
+ }
+ case PNG_COLOR_TYPE_GRAY:
+ {
+ if (row_info->bit_depth == 2)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i += 4)
+ {
+ int a = *sp & 0xc0;
+ int b = *sp & 0x30;
+ int c = *sp & 0x0c;
+ int d = *sp & 0x03;
+
+ *sp = (png_byte)(
+ ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)]) ) & 0xc0)|
+ ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)|
+ ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)|
+ ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) ));
+ sp++;
+ }
+ }
+ if (row_info->bit_depth == 4)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i += 2)
+ {
+ int msb = *sp & 0xf0;
+ int lsb = *sp & 0x0f;
+
+ *sp = (png_byte)((((int)gamma_table[msb | (msb >> 4)]) & 0xf0)
+ | (((int)gamma_table[(lsb << 4) | lsb]) >> 4));
+ sp++;
+ }
+ }
+ else if (row_info->bit_depth == 8)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ *sp = gamma_table[*sp];
+ sp++;
+ }
+ }
+ else if (row_info->bit_depth == 16)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+ *sp = (png_byte)((v >> 8) & 0xff);
+ *(sp + 1) = (png_byte)(v & 0xff);
+ sp += 2;
+ }
+ }
+ break;
+ }
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+/* Expands a palette row to an RGB or RGBA row depending
+ * upon whether you supply trans and num_trans.
+ */
+void /* PRIVATE */
+png_do_expand_palette(png_row_infop row_info, png_bytep row,
+ png_colorp palette, png_bytep trans, int num_trans)
+{
+ int shift, value;
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width=row_info->width;
+
+ png_debug(1, "in png_do_expand_palette\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ row_info->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (row_info->bit_depth < 8)
+ {
+ switch (row_info->bit_depth)
+ {
+ case 1:
+ {
+ sp = row + (png_size_t)((row_width - 1) >> 3);
+ dp = row + (png_size_t)row_width - 1;
+ shift = 7 - (int)((row_width + 7) & 0x07);
+ for (i = 0; i < row_width; i++)
+ {
+ if ((*sp >> shift) & 0x01)
+ *dp = 1;
+ else
+ *dp = 0;
+ if (shift == 7)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift++;
+
+ dp--;
+ }
+ break;
+ }
+ case 2:
+ {
+ sp = row + (png_size_t)((row_width - 1) >> 2);
+ dp = row + (png_size_t)row_width - 1;
+ shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
+ for (i = 0; i < row_width; i++)
+ {
+ value = (*sp >> shift) & 0x03;
+ *dp = (png_byte)value;
+ if (shift == 6)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift += 2;
+
+ dp--;
+ }
+ break;
+ }
+ case 4:
+ {
+ sp = row + (png_size_t)((row_width - 1) >> 1);
+ dp = row + (png_size_t)row_width - 1;
+ shift = (int)((row_width & 0x01) << 2);
+ for (i = 0; i < row_width; i++)
+ {
+ value = (*sp >> shift) & 0x0f;
+ *dp = (png_byte)value;
+ if (shift == 4)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift += 4;
+
+ dp--;
+ }
+ break;
+ }
+ }
+ row_info->bit_depth = 8;
+ row_info->pixel_depth = 8;
+ row_info->rowbytes = row_width;
+ }
+ switch (row_info->bit_depth)
+ {
+ case 8:
+ {
+ if (trans != NULL)
+ {
+ sp = row + (png_size_t)row_width - 1;
+ dp = row + (png_size_t)(row_width << 2) - 1;
+
+ for (i = 0; i < row_width; i++)
+ {
+ if ((int)(*sp) >= num_trans)
+ *dp-- = 0xff;
+ else
+ *dp-- = trans[*sp];
+ *dp-- = palette[*sp].blue;
+ *dp-- = palette[*sp].green;
+ *dp-- = palette[*sp].red;
+ sp--;
+ }
+ row_info->bit_depth = 8;
+ row_info->pixel_depth = 32;
+ row_info->rowbytes = row_width * 4;
+ row_info->color_type = 6;
+ row_info->channels = 4;
+ }
+ else
+ {
+ sp = row + (png_size_t)row_width - 1;
+ dp = row + (png_size_t)(row_width * 3) - 1;
+
+ for (i = 0; i < row_width; i++)
+ {
+ *dp-- = palette[*sp].blue;
+ *dp-- = palette[*sp].green;
+ *dp-- = palette[*sp].red;
+ sp--;
+ }
+ row_info->bit_depth = 8;
+ row_info->pixel_depth = 24;
+ row_info->rowbytes = row_width * 3;
+ row_info->color_type = 2;
+ row_info->channels = 3;
+ }
+ break;
+ }
+ }
+ }
+}
+
+/* If the bit depth < 8, it is expanded to 8. Also, if the already
+ * expanded transparency value is supplied, an alpha channel is built.
+ */
+void /* PRIVATE */
+png_do_expand(png_row_infop row_info, png_bytep row,
+ png_color_16p trans_value)
+{
+ int shift, value;
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width=row_info->width;
+
+ png_debug(1, "in png_do_expand\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL)
+#endif
+ {
+ if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ png_uint_16 gray = (png_uint_16)(trans_value ? trans_value->gray : 0);
+
+ if (row_info->bit_depth < 8)
+ {
+ switch (row_info->bit_depth)
+ {
+ case 1:
+ {
+ gray = (png_uint_16)((gray&0x01)*0xff);
+ sp = row + (png_size_t)((row_width - 1) >> 3);
+ dp = row + (png_size_t)row_width - 1;
+ shift = 7 - (int)((row_width + 7) & 0x07);
+ for (i = 0; i < row_width; i++)
+ {
+ if ((*sp >> shift) & 0x01)
+ *dp = 0xff;
+ else
+ *dp = 0;
+ if (shift == 7)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift++;
+
+ dp--;
+ }
+ break;
+ }
+ case 2:
+ {
+ gray = (png_uint_16)((gray&0x03)*0x55);
+ sp = row + (png_size_t)((row_width - 1) >> 2);
+ dp = row + (png_size_t)row_width - 1;
+ shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
+ for (i = 0; i < row_width; i++)
+ {
+ value = (*sp >> shift) & 0x03;
+ *dp = (png_byte)(value | (value << 2) | (value << 4) |
+ (value << 6));
+ if (shift == 6)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift += 2;
+
+ dp--;
+ }
+ break;
+ }
+ case 4:
+ {
+ gray = (png_uint_16)((gray&0x0f)*0x11);
+ sp = row + (png_size_t)((row_width - 1) >> 1);
+ dp = row + (png_size_t)row_width - 1;
+ shift = (int)((1 - ((row_width + 1) & 0x01)) << 2);
+ for (i = 0; i < row_width; i++)
+ {
+ value = (*sp >> shift) & 0x0f;
+ *dp = (png_byte)(value | (value << 4));
+ if (shift == 4)
+ {
+ shift = 0;
+ sp--;
+ }
+ else
+ shift = 4;
+
+ dp--;
+ }
+ break;
+ }
+ }
+ row_info->bit_depth = 8;
+ row_info->pixel_depth = 8;
+ row_info->rowbytes = row_width;
+ }
+
+ if (trans_value != NULL)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ gray = gray & 0xff;
+ sp = row + (png_size_t)row_width - 1;
+ dp = row + (png_size_t)(row_width << 1) - 1;
+ for (i = 0; i < row_width; i++)
+ {
+ if (*sp == gray)
+ *dp-- = 0;
+ else
+ *dp-- = 0xff;
+ *dp-- = *sp--;
+ }
+ }
+ else if (row_info->bit_depth == 16)
+ {
+ png_byte gray_high = (gray >> 8) & 0xff;
+ png_byte gray_low = gray & 0xff;
+ sp = row + row_info->rowbytes - 1;
+ dp = row + (row_info->rowbytes << 1) - 1;
+ for (i = 0; i < row_width; i++)
+ {
+ if (*(sp-1) == gray_high && *(sp) == gray_low)
+ {
+ *dp-- = 0;
+ *dp-- = 0;
+ }
+ else
+ {
+ *dp-- = 0xff;
+ *dp-- = 0xff;
+ }
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ }
+ }
+ row_info->color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+ row_info->channels = 2;
+ row_info->pixel_depth = (png_byte)(row_info->bit_depth << 1);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+ row_width);
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB && trans_value)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ png_byte red = trans_value->red & 0xff;
+ png_byte green = trans_value->green & 0xff;
+ png_byte blue = trans_value->blue & 0xff;
+ sp = row + (png_size_t)row_info->rowbytes - 1;
+ dp = row + (png_size_t)(row_width << 2) - 1;
+ for (i = 0; i < row_width; i++)
+ {
+ if (*(sp - 2) == red && *(sp - 1) == green && *(sp) == blue)
+ *dp-- = 0;
+ else
+ *dp-- = 0xff;
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ }
+ }
+ else if (row_info->bit_depth == 16)
+ {
+ png_byte red_high = (trans_value->red >> 8) & 0xff;
+ png_byte green_high = (trans_value->green >> 8) & 0xff;
+ png_byte blue_high = (trans_value->blue >> 8) & 0xff;
+ png_byte red_low = trans_value->red & 0xff;
+ png_byte green_low = trans_value->green & 0xff;
+ png_byte blue_low = trans_value->blue & 0xff;
+ sp = row + row_info->rowbytes - 1;
+ dp = row + (png_size_t)(row_width << 3) - 1;
+ for (i = 0; i < row_width; i++)
+ {
+ if (*(sp - 5) == red_high &&
+ *(sp - 4) == red_low &&
+ *(sp - 3) == green_high &&
+ *(sp - 2) == green_low &&
+ *(sp - 1) == blue_high &&
+ *(sp ) == blue_low)
+ {
+ *dp-- = 0;
+ *dp-- = 0;
+ }
+ else
+ {
+ *dp-- = 0xff;
+ *dp-- = 0xff;
+ }
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ *dp-- = *sp--;
+ }
+ }
+ row_info->color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+ row_info->channels = 4;
+ row_info->pixel_depth = (png_byte)(row_info->bit_depth << 2);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+void /* PRIVATE */
+png_do_dither(png_row_infop row_info, png_bytep row,
+ png_bytep palette_lookup, png_bytep dither_lookup)
+{
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width=row_info->width;
+
+ png_debug(1, "in png_do_dither\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL)
+#endif
+ {
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB &&
+ palette_lookup && row_info->bit_depth == 8)
+ {
+ int r, g, b, p;
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ r = *sp++;
+ g = *sp++;
+ b = *sp++;
+
+ /* this looks real messy, but the compiler will reduce
+ it down to a reasonable formula. For example, with
+ 5 bits per color, we get:
+ p = (((r >> 3) & 0x1f) << 10) |
+ (((g >> 3) & 0x1f) << 5) |
+ ((b >> 3) & 0x1f);
+ */
+ p = (((r >> (8 - PNG_DITHER_RED_BITS)) &
+ ((1 << PNG_DITHER_RED_BITS) - 1)) <<
+ (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) |
+ (((g >> (8 - PNG_DITHER_GREEN_BITS)) &
+ ((1 << PNG_DITHER_GREEN_BITS) - 1)) <<
+ (PNG_DITHER_BLUE_BITS)) |
+ ((b >> (8 - PNG_DITHER_BLUE_BITS)) &
+ ((1 << PNG_DITHER_BLUE_BITS) - 1));
+
+ *dp++ = palette_lookup[p];
+ }
+ row_info->color_type = PNG_COLOR_TYPE_PALETTE;
+ row_info->channels = 1;
+ row_info->pixel_depth = row_info->bit_depth;
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
+ palette_lookup != NULL && row_info->bit_depth == 8)
+ {
+ int r, g, b, p;
+ sp = row;
+ dp = row;
+ for (i = 0; i < row_width; i++)
+ {
+ r = *sp++;
+ g = *sp++;
+ b = *sp++;
+ sp++;
+
+ p = (((r >> (8 - PNG_DITHER_RED_BITS)) &
+ ((1 << PNG_DITHER_RED_BITS) - 1)) <<
+ (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) |
+ (((g >> (8 - PNG_DITHER_GREEN_BITS)) &
+ ((1 << PNG_DITHER_GREEN_BITS) - 1)) <<
+ (PNG_DITHER_BLUE_BITS)) |
+ ((b >> (8 - PNG_DITHER_BLUE_BITS)) &
+ ((1 << PNG_DITHER_BLUE_BITS) - 1));
+
+ *dp++ = palette_lookup[p];
+ }
+ row_info->color_type = PNG_COLOR_TYPE_PALETTE;
+ row_info->channels = 1;
+ row_info->pixel_depth = row_info->bit_depth;
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_PALETTE &&
+ dither_lookup && row_info->bit_depth == 8)
+ {
+ sp = row;
+ for (i = 0; i < row_width; i++, sp++)
+ {
+ *sp = dither_lookup[*sp];
+ }
+ }
+ }
+}
+#endif
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+static PNG_CONST int png_gamma_shift[] =
+ {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0, 0x00};
+
+/* We build the 8- or 16-bit gamma tables here. Note that for 16-bit
+ * tables, we don't make a full table if we are reducing to 8-bit in
+ * the future. Note also how the gamma_16 tables are segmented so that
+ * we don't need to allocate > 64K chunks for a full 16-bit table.
+ */
+void /* PRIVATE */
+png_build_gamma_table(png_structp png_ptr)
+{
+ png_debug(1, "in png_build_gamma_table\n");
+
+ if (png_ptr->bit_depth <= 8)
+ {
+ int i;
+ double g;
+
+ if (png_ptr->screen_gamma > .000001)
+ g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+ else
+ g = 1.0;
+
+ png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)256);
+
+ for (i = 0; i < 256; i++)
+ {
+ png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0,
+ g) * 255.0 + .5);
+ }
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+ defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY))
+ {
+
+ g = 1.0 / (png_ptr->gamma);
+
+ png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)256);
+
+ for (i = 0; i < 256; i++)
+ {
+ png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0,
+ g) * 255.0 + .5);
+ }
+
+
+ png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)256);
+
+ if(png_ptr->screen_gamma > 0.000001)
+ g = 1.0 / png_ptr->screen_gamma;
+ else
+ g = png_ptr->gamma; /* probably doing rgb_to_gray */
+
+ for (i = 0; i < 256; i++)
+ {
+ png_ptr->gamma_from_1[i] = (png_byte)(pow((double)i / 255.0,
+ g) * 255.0 + .5);
+
+ }
+ }
+#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
+ }
+ else
+ {
+ double g;
+ int i, j, shift, num;
+ int sig_bit;
+ png_uint_32 ig;
+
+ if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
+ {
+ sig_bit = (int)png_ptr->sig_bit.red;
+ if ((int)png_ptr->sig_bit.green > sig_bit)
+ sig_bit = png_ptr->sig_bit.green;
+ if ((int)png_ptr->sig_bit.blue > sig_bit)
+ sig_bit = png_ptr->sig_bit.blue;
+ }
+ else
+ {
+ sig_bit = (int)png_ptr->sig_bit.gray;
+ }
+
+ if (sig_bit > 0)
+ shift = 16 - sig_bit;
+ else
+ shift = 0;
+
+ if (png_ptr->transformations & PNG_16_TO_8)
+ {
+ if (shift < (16 - PNG_MAX_GAMMA_8))
+ shift = (16 - PNG_MAX_GAMMA_8);
+ }
+
+ if (shift > 8)
+ shift = 8;
+ if (shift < 0)
+ shift = 0;
+
+ png_ptr->gamma_shift = (png_byte)shift;
+
+ num = (1 << (8 - shift));
+
+ if (png_ptr->screen_gamma > .000001)
+ g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+ else
+ g = 1.0;
+
+ png_ptr->gamma_16_table = (png_uint_16pp)png_malloc(png_ptr,
+ (png_uint_32)(num * png_sizeof (png_uint_16p)));
+
+ if (png_ptr->transformations & (PNG_16_TO_8 | PNG_BACKGROUND))
+ {
+ double fin, fout;
+ png_uint_32 last, max;
+
+ for (i = 0; i < num; i++)
+ {
+ png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(256 * png_sizeof (png_uint_16)));
+ }
+
+ g = 1.0 / g;
+ last = 0;
+ for (i = 0; i < 256; i++)
+ {
+ fout = ((double)i + 0.5) / 256.0;
+ fin = pow(fout, g);
+ max = (png_uint_32)(fin * (double)((png_uint_32)num << 8));
+ while (last <= max)
+ {
+ png_ptr->gamma_16_table[(int)(last & (0xff >> shift))]
+ [(int)(last >> (8 - shift))] = (png_uint_16)(
+ (png_uint_16)i | ((png_uint_16)i << 8));
+ last++;
+ }
+ }
+ while (last < ((png_uint_32)num << 8))
+ {
+ png_ptr->gamma_16_table[(int)(last & (0xff >> shift))]
+ [(int)(last >> (8 - shift))] = (png_uint_16)65535L;
+ last++;
+ }
+ }
+ else
+ {
+ for (i = 0; i < num; i++)
+ {
+ png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(256 * png_sizeof (png_uint_16)));
+
+ ig = (((png_uint_32)i * (png_uint_32)png_gamma_shift[shift]) >> 4);
+ for (j = 0; j < 256; j++)
+ {
+ png_ptr->gamma_16_table[i][j] =
+ (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
+ 65535.0, g) * 65535.0 + .5);
+ }
+ }
+ }
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+ defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY))
+ {
+
+ g = 1.0 / (png_ptr->gamma);
+
+ png_ptr->gamma_16_to_1 = (png_uint_16pp)png_malloc(png_ptr,
+ (png_uint_32)(num * png_sizeof (png_uint_16p )));
+
+ for (i = 0; i < num; i++)
+ {
+ png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(256 * png_sizeof (png_uint_16)));
+
+ ig = (((png_uint_32)i *
+ (png_uint_32)png_gamma_shift[shift]) >> 4);
+ for (j = 0; j < 256; j++)
+ {
+ png_ptr->gamma_16_to_1[i][j] =
+ (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
+ 65535.0, g) * 65535.0 + .5);
+ }
+ }
+
+ if(png_ptr->screen_gamma > 0.000001)
+ g = 1.0 / png_ptr->screen_gamma;
+ else
+ g = png_ptr->gamma; /* probably doing rgb_to_gray */
+
+ png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr,
+ (png_uint_32)(num * png_sizeof (png_uint_16p)));
+
+ for (i = 0; i < num; i++)
+ {
+ png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(256 * png_sizeof (png_uint_16)));
+
+ ig = (((png_uint_32)i *
+ (png_uint_32)png_gamma_shift[shift]) >> 4);
+ for (j = 0; j < 256; j++)
+ {
+ png_ptr->gamma_16_from_1[i][j] =
+ (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
+ 65535.0, g) * 65535.0 + .5);
+ }
+ }
+ }
+#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
+ }
+}
+#endif
+/* To do: install integer version of png_build_gamma_table here */
+#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+/* undoes intrapixel differencing */
+void /* PRIVATE */
+png_do_read_intrapixel(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_read_intrapixel\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ (row_info->color_type & PNG_COLOR_MASK_COLOR))
+ {
+ int bytes_per_pixel;
+ png_uint_32 row_width = row_info->width;
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ bytes_per_pixel = 3;
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 4;
+ else
+ return;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ *(rp) = (png_byte)((256 + *rp + *(rp+1))&0xff);
+ *(rp+2) = (png_byte)((256 + *(rp+2) + *(rp+1))&0xff);
+ }
+ }
+ else if (row_info->bit_depth == 16)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ bytes_per_pixel = 6;
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 8;
+ else
+ return;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ png_uint_32 s0 = (*(rp ) << 8) | *(rp+1);
+ png_uint_32 s1 = (*(rp+2) << 8) | *(rp+3);
+ png_uint_32 s2 = (*(rp+4) << 8) | *(rp+5);
+ png_uint_32 red = (png_uint_32)((s0+s1+65536L) & 0xffffL);
+ png_uint_32 blue = (png_uint_32)((s2+s1+65536L) & 0xffffL);
+ *(rp ) = (png_byte)((red >> 8) & 0xff);
+ *(rp+1) = (png_byte)(red & 0xff);
+ *(rp+4) = (png_byte)((blue >> 8) & 0xff);
+ *(rp+5) = (png_byte)(blue & 0xff);
+ }
+ }
+ }
+}
+#endif /* PNG_MNG_FEATURES_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED */
diff --git a/src/libpng/pngrutil.c b/src/libpng/pngrutil.c
new file mode 100644
index 0000000..ad4f1a9
--- /dev/null
+++ b/src/libpng/pngrutil.c
@@ -0,0 +1,3163 @@
+
+/* pngrutil.c - utilities to read a PNG file
+ *
+ * Last changed in libpng 1.2.22 [October 13, 2007]
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file contains routines that are only called from within
+ * libpng itself during the course of reading an image.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED)
+
+#if defined(_WIN32_WCE) && (_WIN32_WCE<0x500)
+# define WIN32_WCE_OLD
+#endif
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+# if defined(WIN32_WCE_OLD)
+/* strtod() function is not supported on WindowsCE */
+__inline double png_strtod(png_structp png_ptr, PNG_CONST char *nptr, char **endptr)
+{
+ double result = 0;
+ int len;
+ wchar_t *str, *end;
+
+ len = MultiByteToWideChar(CP_ACP, 0, nptr, -1, NULL, 0);
+ str = (wchar_t *)png_malloc(png_ptr, len * sizeof(wchar_t));
+ if ( NULL != str )
+ {
+ MultiByteToWideChar(CP_ACP, 0, nptr, -1, str, len);
+ result = wcstod(str, &end);
+ len = WideCharToMultiByte(CP_ACP, 0, end, -1, NULL, 0, NULL, NULL);
+ *endptr = (char *)nptr + (png_strlen(nptr) - len + 1);
+ png_free(png_ptr, str);
+ }
+ return result;
+}
+# else
+# define png_strtod(p,a,b) strtod(a,b)
+# endif
+#endif
+
+png_uint_32 PNGAPI
+png_get_uint_31(png_structp png_ptr, png_bytep buf)
+{
+ png_uint_32 i = png_get_uint_32(buf);
+ if (i > PNG_UINT_31_MAX)
+ png_error(png_ptr, "PNG unsigned integer out of range.");
+ return (i);
+}
+#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
+/* Grab an unsigned 32-bit integer from a buffer in big-endian format. */
+png_uint_32 PNGAPI
+png_get_uint_32(png_bytep buf)
+{
+ png_uint_32 i = ((png_uint_32)(*buf) << 24) +
+ ((png_uint_32)(*(buf + 1)) << 16) +
+ ((png_uint_32)(*(buf + 2)) << 8) +
+ (png_uint_32)(*(buf + 3));
+
+ return (i);
+}
+
+/* Grab a signed 32-bit integer from a buffer in big-endian format. The
+ * data is stored in the PNG file in two's complement format, and it is
+ * assumed that the machine format for signed integers is the same. */
+png_int_32 PNGAPI
+png_get_int_32(png_bytep buf)
+{
+ png_int_32 i = ((png_int_32)(*buf) << 24) +
+ ((png_int_32)(*(buf + 1)) << 16) +
+ ((png_int_32)(*(buf + 2)) << 8) +
+ (png_int_32)(*(buf + 3));
+
+ return (i);
+}
+
+/* Grab an unsigned 16-bit integer from a buffer in big-endian format. */
+png_uint_16 PNGAPI
+png_get_uint_16(png_bytep buf)
+{
+ png_uint_16 i = (png_uint_16)(((png_uint_16)(*buf) << 8) +
+ (png_uint_16)(*(buf + 1)));
+
+ return (i);
+}
+#endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
+
+/* Read data, and (optionally) run it through the CRC. */
+void /* PRIVATE */
+png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)
+{
+ if(png_ptr == NULL) return;
+ png_read_data(png_ptr, buf, length);
+ png_calculate_crc(png_ptr, buf, length);
+}
+
+/* Optionally skip data and then check the CRC. Depending on whether we
+ are reading a ancillary or critical chunk, and how the program has set
+ things up, we may calculate the CRC on the data and print a message.
+ Returns '1' if there was a CRC error, '0' otherwise. */
+int /* PRIVATE */
+png_crc_finish(png_structp png_ptr, png_uint_32 skip)
+{
+ png_size_t i;
+ png_size_t istop = png_ptr->zbuf_size;
+
+ for (i = (png_size_t)skip; i > istop; i -= istop)
+ {
+ png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
+ }
+ if (i)
+ {
+ png_crc_read(png_ptr, png_ptr->zbuf, i);
+ }
+
+ if (png_crc_error(png_ptr))
+ {
+ if (((png_ptr->chunk_name[0] & 0x20) && /* Ancillary */
+ !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) ||
+ (!(png_ptr->chunk_name[0] & 0x20) && /* Critical */
+ (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE)))
+ {
+ png_chunk_warning(png_ptr, "CRC error");
+ }
+ else
+ {
+ png_chunk_error(png_ptr, "CRC error");
+ }
+ return (1);
+ }
+
+ return (0);
+}
+
+/* Compare the CRC stored in the PNG file with that calculated by libpng from
+ the data it has read thus far. */
+int /* PRIVATE */
+png_crc_error(png_structp png_ptr)
+{
+ png_byte crc_bytes[4];
+ png_uint_32 crc;
+ int need_crc = 1;
+
+ if (png_ptr->chunk_name[0] & 0x20) /* ancillary */
+ {
+ if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
+ (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
+ need_crc = 0;
+ }
+ else /* critical */
+ {
+ if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
+ need_crc = 0;
+ }
+
+ png_read_data(png_ptr, crc_bytes, 4);
+
+ if (need_crc)
+ {
+ crc = png_get_uint_32(crc_bytes);
+ return ((int)(crc != png_ptr->crc));
+ }
+ else
+ return (0);
+}
+
+#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \
+ defined(PNG_READ_iCCP_SUPPORTED)
+/*
+ * Decompress trailing data in a chunk. The assumption is that chunkdata
+ * points at an allocated area holding the contents of a chunk with a
+ * trailing compressed part. What we get back is an allocated area
+ * holding the original prefix part and an uncompressed version of the
+ * trailing part (the malloc area passed in is freed).
+ */
+png_charp /* PRIVATE */
+png_decompress_chunk(png_structp png_ptr, int comp_type,
+ png_charp chunkdata, png_size_t chunklength,
+ png_size_t prefix_size, png_size_t *newlength)
+{
+ static PNG_CONST char msg[] = "Error decoding compressed text";
+ png_charp text;
+ png_size_t text_size;
+
+ if (comp_type == PNG_COMPRESSION_TYPE_BASE)
+ {
+ int ret = Z_OK;
+ png_ptr->zstream.next_in = (png_bytep)(chunkdata + prefix_size);
+ png_ptr->zstream.avail_in = (uInt)(chunklength - prefix_size);
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+ text_size = 0;
+ text = NULL;
+
+ while (png_ptr->zstream.avail_in)
+ {
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+ if (ret != Z_OK && ret != Z_STREAM_END)
+ {
+ if (png_ptr->zstream.msg != NULL)
+ png_warning(png_ptr, png_ptr->zstream.msg);
+ else
+ png_warning(png_ptr, msg);
+ inflateReset(&png_ptr->zstream);
+ png_ptr->zstream.avail_in = 0;
+
+ if (text == NULL)
+ {
+ text_size = prefix_size + png_sizeof(msg) + 1;
+ text = (png_charp)png_malloc_warn(png_ptr, text_size);
+ if (text == NULL)
+ {
+ png_free(png_ptr,chunkdata);
+ png_error(png_ptr,"Not enough memory to decompress chunk");
+ }
+ png_memcpy(text, chunkdata, prefix_size);
+ }
+
+ text[text_size - 1] = 0x00;
+
+ /* Copy what we can of the error message into the text chunk */
+ text_size = (png_size_t)(chunklength - (text - chunkdata) - 1);
+ text_size = png_sizeof(msg) > text_size ? text_size :
+ png_sizeof(msg);
+ png_memcpy(text + prefix_size, msg, text_size + 1);
+ break;
+ }
+ if (!png_ptr->zstream.avail_out || ret == Z_STREAM_END)
+ {
+ if (text == NULL)
+ {
+ text_size = prefix_size +
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+ text = (png_charp)png_malloc_warn(png_ptr, text_size + 1);
+ if (text == NULL)
+ {
+ png_free(png_ptr,chunkdata);
+ png_error(png_ptr,"Not enough memory to decompress chunk.");
+ }
+ png_memcpy(text + prefix_size, png_ptr->zbuf,
+ text_size - prefix_size);
+ png_memcpy(text, chunkdata, prefix_size);
+ *(text + text_size) = 0x00;
+ }
+ else
+ {
+ png_charp tmp;
+
+ tmp = text;
+ text = (png_charp)png_malloc_warn(png_ptr,
+ (png_uint_32)(text_size +
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1));
+ if (text == NULL)
+ {
+ png_free(png_ptr, tmp);
+ png_free(png_ptr, chunkdata);
+ png_error(png_ptr,"Not enough memory to decompress chunk..");
+ }
+ png_memcpy(text, tmp, text_size);
+ png_free(png_ptr, tmp);
+ png_memcpy(text + text_size, png_ptr->zbuf,
+ (png_ptr->zbuf_size - png_ptr->zstream.avail_out));
+ text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+ *(text + text_size) = 0x00;
+ }
+ if (ret == Z_STREAM_END)
+ break;
+ else
+ {
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ }
+ }
+ }
+ if (ret != Z_STREAM_END)
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char umsg[52];
+
+ if (ret == Z_BUF_ERROR)
+ png_snprintf(umsg, 52,
+ "Buffer error in compressed datastream in %s chunk",
+ png_ptr->chunk_name);
+ else if (ret == Z_DATA_ERROR)
+ png_snprintf(umsg, 52,
+ "Data error in compressed datastream in %s chunk",
+ png_ptr->chunk_name);
+ else
+ png_snprintf(umsg, 52,
+ "Incomplete compressed datastream in %s chunk",
+ png_ptr->chunk_name);
+ png_warning(png_ptr, umsg);
+#else
+ png_warning(png_ptr,
+ "Incomplete compressed datastream in chunk other than IDAT");
+#endif
+ text_size=prefix_size;
+ if (text == NULL)
+ {
+ text = (png_charp)png_malloc_warn(png_ptr, text_size+1);
+ if (text == NULL)
+ {
+ png_free(png_ptr, chunkdata);
+ png_error(png_ptr,"Not enough memory for text.");
+ }
+ png_memcpy(text, chunkdata, prefix_size);
+ }
+ *(text + text_size) = 0x00;
+ }
+
+ inflateReset(&png_ptr->zstream);
+ png_ptr->zstream.avail_in = 0;
+
+ png_free(png_ptr, chunkdata);
+ chunkdata = text;
+ *newlength=text_size;
+ }
+ else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char umsg[50];
+
+ png_snprintf(umsg, 50,
+ "Unknown zTXt compression type %d", comp_type);
+ png_warning(png_ptr, umsg);
+#else
+ png_warning(png_ptr, "Unknown zTXt compression type");
+#endif
+
+ *(chunkdata + prefix_size) = 0x00;
+ *newlength=prefix_size;
+ }
+
+ return chunkdata;
+}
+#endif
+
+/* read and check the IDHR chunk */
+void /* PRIVATE */
+png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_byte buf[13];
+ png_uint_32 width, height;
+ int bit_depth, color_type, compression_type, filter_type;
+ int interlace_type;
+
+ png_debug(1, "in png_handle_IHDR\n");
+
+ if (png_ptr->mode & PNG_HAVE_IHDR)
+ png_error(png_ptr, "Out of place IHDR");
+
+ /* check the length */
+ if (length != 13)
+ png_error(png_ptr, "Invalid IHDR chunk");
+
+ png_ptr->mode |= PNG_HAVE_IHDR;
+
+ png_crc_read(png_ptr, buf, 13);
+ png_crc_finish(png_ptr, 0);
+
+ width = png_get_uint_31(png_ptr, buf);
+ height = png_get_uint_31(png_ptr, buf + 4);
+ bit_depth = buf[8];
+ color_type = buf[9];
+ compression_type = buf[10];
+ filter_type = buf[11];
+ interlace_type = buf[12];
+
+ /* set internal variables */
+ png_ptr->width = width;
+ png_ptr->height = height;
+ png_ptr->bit_depth = (png_byte)bit_depth;
+ png_ptr->interlaced = (png_byte)interlace_type;
+ png_ptr->color_type = (png_byte)color_type;
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ png_ptr->filter_type = (png_byte)filter_type;
+#endif
+ png_ptr->compression_type = (png_byte)compression_type;
+
+ /* find number of channels */
+ switch (png_ptr->color_type)
+ {
+ case PNG_COLOR_TYPE_GRAY:
+ case PNG_COLOR_TYPE_PALETTE:
+ png_ptr->channels = 1;
+ break;
+ case PNG_COLOR_TYPE_RGB:
+ png_ptr->channels = 3;
+ break;
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ png_ptr->channels = 2;
+ break;
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ png_ptr->channels = 4;
+ break;
+ }
+
+ /* set up other useful info */
+ png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth *
+ png_ptr->channels);
+ png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,png_ptr->width);
+ png_debug1(3,"bit_depth = %d\n", png_ptr->bit_depth);
+ png_debug1(3,"channels = %d\n", png_ptr->channels);
+ png_debug1(3,"rowbytes = %lu\n", png_ptr->rowbytes);
+ png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,
+ color_type, interlace_type, compression_type, filter_type);
+}
+
+/* read and check the palette */
+void /* PRIVATE */
+png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_color palette[PNG_MAX_PALETTE_LENGTH];
+ int num, i;
+#ifndef PNG_NO_POINTER_INDEXING
+ png_colorp pal_ptr;
+#endif
+
+ png_debug(1, "in png_handle_PLTE\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before PLTE");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid PLTE after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (png_ptr->mode & PNG_HAVE_PLTE)
+ png_error(png_ptr, "Duplicate PLTE chunk");
+
+ png_ptr->mode |= PNG_HAVE_PLTE;
+
+ if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
+ {
+ png_warning(png_ptr,
+ "Ignoring PLTE chunk in grayscale PNG");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+ if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
+ {
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+#endif
+
+ if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3)
+ {
+ if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
+ {
+ png_warning(png_ptr, "Invalid palette chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else
+ {
+ png_error(png_ptr, "Invalid palette chunk");
+ }
+ }
+
+ num = (int)length / 3;
+
+#ifndef PNG_NO_POINTER_INDEXING
+ for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++)
+ {
+ png_byte buf[3];
+
+ png_crc_read(png_ptr, buf, 3);
+ pal_ptr->red = buf[0];
+ pal_ptr->green = buf[1];
+ pal_ptr->blue = buf[2];
+ }
+#else
+ for (i = 0; i < num; i++)
+ {
+ png_byte buf[3];
+
+ png_crc_read(png_ptr, buf, 3);
+ /* don't depend upon png_color being any order */
+ palette[i].red = buf[0];
+ palette[i].green = buf[1];
+ palette[i].blue = buf[2];
+ }
+#endif
+
+ /* If we actually NEED the PLTE chunk (ie for a paletted image), we do
+ whatever the normal CRC configuration tells us. However, if we
+ have an RGB image, the PLTE can be considered ancillary, so
+ we will act as though it is. */
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+#endif
+ {
+ png_crc_finish(png_ptr, 0);
+ }
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+ else if (png_crc_error(png_ptr)) /* Only if we have a CRC error */
+ {
+ /* If we don't want to use the data from an ancillary chunk,
+ we have two options: an error abort, or a warning and we
+ ignore the data in this chunk (which should be OK, since
+ it's considered ancillary for a RGB or RGBA image). */
+ if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE))
+ {
+ if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)
+ {
+ png_chunk_error(png_ptr, "CRC error");
+ }
+ else
+ {
+ png_chunk_warning(png_ptr, "CRC error");
+ return;
+ }
+ }
+ /* Otherwise, we (optionally) emit a warning and use the chunk. */
+ else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN))
+ {
+ png_chunk_warning(png_ptr, "CRC error");
+ }
+ }
+#endif
+
+ png_set_PLTE(png_ptr, info_ptr, palette, num);
+
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+ {
+ if (png_ptr->num_trans > (png_uint_16)num)
+ {
+ png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
+ png_ptr->num_trans = (png_uint_16)num;
+ }
+ if (info_ptr->num_trans > (png_uint_16)num)
+ {
+ png_warning(png_ptr, "Truncating incorrect info tRNS chunk length");
+ info_ptr->num_trans = (png_uint_16)num;
+ }
+ }
+ }
+#endif
+
+}
+
+void /* PRIVATE */
+png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_debug(1, "in png_handle_IEND\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT))
+ {
+ png_error(png_ptr, "No image in file");
+ }
+
+ png_ptr->mode |= (PNG_AFTER_IDAT | PNG_HAVE_IEND);
+
+ if (length != 0)
+ {
+ png_warning(png_ptr, "Incorrect IEND chunk length");
+ }
+ png_crc_finish(png_ptr, length);
+
+ info_ptr =info_ptr; /* quiet compiler warnings about unused info_ptr */
+}
+
+#if defined(PNG_READ_gAMA_SUPPORTED)
+void /* PRIVATE */
+png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_fixed_point igamma;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float file_gamma;
+#endif
+ png_byte buf[4];
+
+ png_debug(1, "in png_handle_gAMA\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before gAMA");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid gAMA after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (png_ptr->mode & PNG_HAVE_PLTE)
+ /* Should be an error, but we can cope with it */
+ png_warning(png_ptr, "Out of place gAMA chunk");
+
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ && !(info_ptr->valid & PNG_INFO_sRGB)
+#endif
+ )
+ {
+ png_warning(png_ptr, "Duplicate gAMA chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (length != 4)
+ {
+ png_warning(png_ptr, "Incorrect gAMA chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, 4);
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ igamma = (png_fixed_point)png_get_uint_32(buf);
+ /* check for zero gamma */
+ if (igamma == 0)
+ {
+ png_warning(png_ptr,
+ "Ignoring gAMA chunk with gamma=0");
+ return;
+ }
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
+ if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
+ {
+ png_warning(png_ptr,
+ "Ignoring incorrect gAMA value when sRGB is also present");
+#ifndef PNG_NO_CONSOLE_IO
+ fprintf(stderr, "gamma = (%d/100000)\n", (int)igamma);
+#endif
+ return;
+ }
+#endif /* PNG_READ_sRGB_SUPPORTED */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ file_gamma = (float)igamma / (float)100000.0;
+# ifdef PNG_READ_GAMMA_SUPPORTED
+ png_ptr->gamma = file_gamma;
+# endif
+ png_set_gAMA(png_ptr, info_ptr, file_gamma);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_set_gAMA_fixed(png_ptr, info_ptr, igamma);
+#endif
+}
+#endif
+
+#if defined(PNG_READ_sBIT_SUPPORTED)
+void /* PRIVATE */
+png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_size_t truelen;
+ png_byte buf[4];
+
+ png_debug(1, "in png_handle_sBIT\n");
+
+ buf[0] = buf[1] = buf[2] = buf[3] = 0;
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before sBIT");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid sBIT after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (png_ptr->mode & PNG_HAVE_PLTE)
+ {
+ /* Should be an error, but we can cope with it */
+ png_warning(png_ptr, "Out of place sBIT chunk");
+ }
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT))
+ {
+ png_warning(png_ptr, "Duplicate sBIT chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ truelen = 3;
+ else
+ truelen = (png_size_t)png_ptr->channels;
+
+ if (length != truelen || length > 4)
+ {
+ png_warning(png_ptr, "Incorrect sBIT chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, truelen);
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
+ {
+ png_ptr->sig_bit.red = buf[0];
+ png_ptr->sig_bit.green = buf[1];
+ png_ptr->sig_bit.blue = buf[2];
+ png_ptr->sig_bit.alpha = buf[3];
+ }
+ else
+ {
+ png_ptr->sig_bit.gray = buf[0];
+ png_ptr->sig_bit.red = buf[0];
+ png_ptr->sig_bit.green = buf[0];
+ png_ptr->sig_bit.blue = buf[0];
+ png_ptr->sig_bit.alpha = buf[1];
+ }
+ png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit));
+}
+#endif
+
+#if defined(PNG_READ_cHRM_SUPPORTED)
+void /* PRIVATE */
+png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_byte buf[4];
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
+#endif
+ png_fixed_point int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
+ int_y_green, int_x_blue, int_y_blue;
+
+ png_uint_32 uint_x, uint_y;
+
+ png_debug(1, "in png_handle_cHRM\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before cHRM");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid cHRM after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (png_ptr->mode & PNG_HAVE_PLTE)
+ /* Should be an error, but we can cope with it */
+ png_warning(png_ptr, "Missing PLTE before cHRM");
+
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ && !(info_ptr->valid & PNG_INFO_sRGB)
+#endif
+ )
+ {
+ png_warning(png_ptr, "Duplicate cHRM chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (length != 32)
+ {
+ png_warning(png_ptr, "Incorrect cHRM chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_x = png_get_uint_32(buf);
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_y = png_get_uint_32(buf);
+
+ if (uint_x > 80000L || uint_y > 80000L ||
+ uint_x + uint_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid cHRM white point");
+ png_crc_finish(png_ptr, 24);
+ return;
+ }
+ int_x_white = (png_fixed_point)uint_x;
+ int_y_white = (png_fixed_point)uint_y;
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_x = png_get_uint_32(buf);
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_y = png_get_uint_32(buf);
+
+ if (uint_x + uint_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid cHRM red point");
+ png_crc_finish(png_ptr, 16);
+ return;
+ }
+ int_x_red = (png_fixed_point)uint_x;
+ int_y_red = (png_fixed_point)uint_y;
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_x = png_get_uint_32(buf);
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_y = png_get_uint_32(buf);
+
+ if (uint_x + uint_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid cHRM green point");
+ png_crc_finish(png_ptr, 8);
+ return;
+ }
+ int_x_green = (png_fixed_point)uint_x;
+ int_y_green = (png_fixed_point)uint_y;
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_x = png_get_uint_32(buf);
+
+ png_crc_read(png_ptr, buf, 4);
+ uint_y = png_get_uint_32(buf);
+
+ if (uint_x + uint_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid cHRM blue point");
+ png_crc_finish(png_ptr, 0);
+ return;
+ }
+ int_x_blue = (png_fixed_point)uint_x;
+ int_y_blue = (png_fixed_point)uint_y;
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ white_x = (float)int_x_white / (float)100000.0;
+ white_y = (float)int_y_white / (float)100000.0;
+ red_x = (float)int_x_red / (float)100000.0;
+ red_y = (float)int_y_red / (float)100000.0;
+ green_x = (float)int_x_green / (float)100000.0;
+ green_y = (float)int_y_green / (float)100000.0;
+ blue_x = (float)int_x_blue / (float)100000.0;
+ blue_y = (float)int_y_blue / (float)100000.0;
+#endif
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ if ((info_ptr != NULL) && (info_ptr->valid & PNG_INFO_sRGB))
+ {
+ if (PNG_OUT_OF_RANGE(int_x_white, 31270, 1000) ||
+ PNG_OUT_OF_RANGE(int_y_white, 32900, 1000) ||
+ PNG_OUT_OF_RANGE(int_x_red, 64000L, 1000) ||
+ PNG_OUT_OF_RANGE(int_y_red, 33000, 1000) ||
+ PNG_OUT_OF_RANGE(int_x_green, 30000, 1000) ||
+ PNG_OUT_OF_RANGE(int_y_green, 60000L, 1000) ||
+ PNG_OUT_OF_RANGE(int_x_blue, 15000, 1000) ||
+ PNG_OUT_OF_RANGE(int_y_blue, 6000, 1000))
+ {
+ png_warning(png_ptr,
+ "Ignoring incorrect cHRM value when sRGB is also present");
+#ifndef PNG_NO_CONSOLE_IO
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ fprintf(stderr,"wx=%f, wy=%f, rx=%f, ry=%f\n",
+ white_x, white_y, red_x, red_y);
+ fprintf(stderr,"gx=%f, gy=%f, bx=%f, by=%f\n",
+ green_x, green_y, blue_x, blue_y);
+#else
+ fprintf(stderr,"wx=%ld, wy=%ld, rx=%ld, ry=%ld\n",
+ int_x_white, int_y_white, int_x_red, int_y_red);
+ fprintf(stderr,"gx=%ld, gy=%ld, bx=%ld, by=%ld\n",
+ int_x_green, int_y_green, int_x_blue, int_y_blue);
+#endif
+#endif /* PNG_NO_CONSOLE_IO */
+ }
+ png_crc_finish(png_ptr, 0);
+ return;
+ }
+#endif /* PNG_READ_sRGB_SUPPORTED */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ png_set_cHRM(png_ptr, info_ptr,
+ white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_set_cHRM_fixed(png_ptr, info_ptr,
+ int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
+ int_y_green, int_x_blue, int_y_blue);
+#endif
+ if (png_crc_finish(png_ptr, 0))
+ return;
+}
+#endif
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+void /* PRIVATE */
+png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ int intent;
+ png_byte buf[1];
+
+ png_debug(1, "in png_handle_sRGB\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before sRGB");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid sRGB after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (png_ptr->mode & PNG_HAVE_PLTE)
+ /* Should be an error, but we can cope with it */
+ png_warning(png_ptr, "Out of place sRGB chunk");
+
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
+ {
+ png_warning(png_ptr, "Duplicate sRGB chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (length != 1)
+ {
+ png_warning(png_ptr, "Incorrect sRGB chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, 1);
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ intent = buf[0];
+ /* check for bad intent */
+ if (intent >= PNG_sRGB_INTENT_LAST)
+ {
+ png_warning(png_ptr, "Unknown sRGB intent");
+ return;
+ }
+
+#if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA))
+ {
+ png_fixed_point igamma;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ igamma=info_ptr->int_gamma;
+#else
+# ifdef PNG_FLOATING_POINT_SUPPORTED
+ igamma=(png_fixed_point)(info_ptr->gamma * 100000.);
+# endif
+#endif
+ if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
+ {
+ png_warning(png_ptr,
+ "Ignoring incorrect gAMA value when sRGB is also present");
+#ifndef PNG_NO_CONSOLE_IO
+# ifdef PNG_FIXED_POINT_SUPPORTED
+ fprintf(stderr,"incorrect gamma=(%d/100000)\n",(int)png_ptr->int_gamma);
+# else
+# ifdef PNG_FLOATING_POINT_SUPPORTED
+ fprintf(stderr,"incorrect gamma=%f\n",png_ptr->gamma);
+# endif
+# endif
+#endif
+ }
+ }
+#endif /* PNG_READ_gAMA_SUPPORTED */
+
+#ifdef PNG_READ_cHRM_SUPPORTED
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
+ if (PNG_OUT_OF_RANGE(info_ptr->int_x_white, 31270, 1000) ||
+ PNG_OUT_OF_RANGE(info_ptr->int_y_white, 32900, 1000) ||
+ PNG_OUT_OF_RANGE(info_ptr->int_x_red, 64000L, 1000) ||
+ PNG_OUT_OF_RANGE(info_ptr->int_y_red, 33000, 1000) ||
+ PNG_OUT_OF_RANGE(info_ptr->int_x_green, 30000, 1000) ||
+ PNG_OUT_OF_RANGE(info_ptr->int_y_green, 60000L, 1000) ||
+ PNG_OUT_OF_RANGE(info_ptr->int_x_blue, 15000, 1000) ||
+ PNG_OUT_OF_RANGE(info_ptr->int_y_blue, 6000, 1000))
+ {
+ png_warning(png_ptr,
+ "Ignoring incorrect cHRM value when sRGB is also present");
+ }
+#endif /* PNG_FIXED_POINT_SUPPORTED */
+#endif /* PNG_READ_cHRM_SUPPORTED */
+
+ png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent);
+}
+#endif /* PNG_READ_sRGB_SUPPORTED */
+
+#if defined(PNG_READ_iCCP_SUPPORTED)
+void /* PRIVATE */
+png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+/* Note: this does not properly handle chunks that are > 64K under DOS */
+{
+ png_charp chunkdata;
+ png_byte compression_type;
+ png_bytep pC;
+ png_charp profile;
+ png_uint_32 skip = 0;
+ png_uint_32 profile_size, profile_length;
+ png_size_t slength, prefix_length, data_length;
+
+ png_debug(1, "in png_handle_iCCP\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before iCCP");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid iCCP after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (png_ptr->mode & PNG_HAVE_PLTE)
+ /* Should be an error, but we can cope with it */
+ png_warning(png_ptr, "Out of place iCCP chunk");
+
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP))
+ {
+ png_warning(png_ptr, "Duplicate iCCP chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "iCCP chunk too large to fit in memory");
+ skip = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+
+ chunkdata = (png_charp)png_malloc(png_ptr, length + 1);
+ slength = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+
+ if (png_crc_finish(png_ptr, skip))
+ {
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+
+ chunkdata[slength] = 0x00;
+
+ for (profile = chunkdata; *profile; profile++)
+ /* empty loop to find end of name */ ;
+
+ ++profile;
+
+ /* there should be at least one zero (the compression type byte)
+ following the separator, and we should be on it */
+ if ( profile >= chunkdata + slength - 1)
+ {
+ png_free(png_ptr, chunkdata);
+ png_warning(png_ptr, "Malformed iCCP chunk");
+ return;
+ }
+
+ /* compression_type should always be zero */
+ compression_type = *profile++;
+ if (compression_type)
+ {
+ png_warning(png_ptr, "Ignoring nonzero compression type in iCCP chunk");
+ compression_type=0x00; /* Reset it to zero (libpng-1.0.6 through 1.0.8
+ wrote nonzero) */
+ }
+
+ prefix_length = profile - chunkdata;
+ chunkdata = png_decompress_chunk(png_ptr, compression_type, chunkdata,
+ slength, prefix_length, &data_length);
+
+ profile_length = data_length - prefix_length;
+
+ if ( prefix_length > data_length || profile_length < 4)
+ {
+ png_free(png_ptr, chunkdata);
+ png_warning(png_ptr, "Profile size field missing from iCCP chunk");
+ return;
+ }
+
+ /* Check the profile_size recorded in the first 32 bits of the ICC profile */
+ pC = (png_bytep)(chunkdata+prefix_length);
+ profile_size = ((*(pC ))<<24) |
+ ((*(pC+1))<<16) |
+ ((*(pC+2))<< 8) |
+ ((*(pC+3)) );
+
+ if(profile_size < profile_length)
+ profile_length = profile_size;
+
+ if(profile_size > profile_length)
+ {
+ png_free(png_ptr, chunkdata);
+ png_warning(png_ptr, "Ignoring truncated iCCP profile.");
+ return;
+ }
+
+ png_set_iCCP(png_ptr, info_ptr, chunkdata, compression_type,
+ chunkdata + prefix_length, profile_length);
+ png_free(png_ptr, chunkdata);
+}
+#endif /* PNG_READ_iCCP_SUPPORTED */
+
+#if defined(PNG_READ_sPLT_SUPPORTED)
+void /* PRIVATE */
+png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+/* Note: this does not properly handle chunks that are > 64K under DOS */
+{
+ png_bytep chunkdata;
+ png_bytep entry_start;
+ png_sPLT_t new_palette;
+#ifdef PNG_NO_POINTER_INDEXING
+ png_sPLT_entryp pp;
+#endif
+ int data_length, entry_size, i;
+ png_uint_32 skip = 0;
+ png_size_t slength;
+
+ png_debug(1, "in png_handle_sPLT\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before sPLT");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid sPLT after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "sPLT chunk too large to fit in memory");
+ skip = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+
+ chunkdata = (png_bytep)png_malloc(png_ptr, length + 1);
+ slength = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+
+ if (png_crc_finish(png_ptr, skip))
+ {
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+
+ chunkdata[slength] = 0x00;
+
+ for (entry_start = chunkdata; *entry_start; entry_start++)
+ /* empty loop to find end of name */ ;
+ ++entry_start;
+
+ /* a sample depth should follow the separator, and we should be on it */
+ if (entry_start > chunkdata + slength - 2)
+ {
+ png_free(png_ptr, chunkdata);
+ png_warning(png_ptr, "malformed sPLT chunk");
+ return;
+ }
+
+ new_palette.depth = *entry_start++;
+ entry_size = (new_palette.depth == 8 ? 6 : 10);
+ data_length = (slength - (entry_start - chunkdata));
+
+ /* integrity-check the data length */
+ if (data_length % entry_size)
+ {
+ png_free(png_ptr, chunkdata);
+ png_warning(png_ptr, "sPLT chunk has bad length");
+ return;
+ }
+
+ new_palette.nentries = (png_int_32) ( data_length / entry_size);
+ if ((png_uint_32) new_palette.nentries > (png_uint_32) (PNG_SIZE_MAX /
+ png_sizeof(png_sPLT_entry)))
+ {
+ png_warning(png_ptr, "sPLT chunk too long");
+ return;
+ }
+ new_palette.entries = (png_sPLT_entryp)png_malloc_warn(
+ png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry));
+ if (new_palette.entries == NULL)
+ {
+ png_warning(png_ptr, "sPLT chunk requires too much memory");
+ return;
+ }
+
+#ifndef PNG_NO_POINTER_INDEXING
+ for (i = 0; i < new_palette.nentries; i++)
+ {
+ png_sPLT_entryp pp = new_palette.entries + i;
+
+ if (new_palette.depth == 8)
+ {
+ pp->red = *entry_start++;
+ pp->green = *entry_start++;
+ pp->blue = *entry_start++;
+ pp->alpha = *entry_start++;
+ }
+ else
+ {
+ pp->red = png_get_uint_16(entry_start); entry_start += 2;
+ pp->green = png_get_uint_16(entry_start); entry_start += 2;
+ pp->blue = png_get_uint_16(entry_start); entry_start += 2;
+ pp->alpha = png_get_uint_16(entry_start); entry_start += 2;
+ }
+ pp->frequency = png_get_uint_16(entry_start); entry_start += 2;
+ }
+#else
+ pp = new_palette.entries;
+ for (i = 0; i < new_palette.nentries; i++)
+ {
+
+ if (new_palette.depth == 8)
+ {
+ pp[i].red = *entry_start++;
+ pp[i].green = *entry_start++;
+ pp[i].blue = *entry_start++;
+ pp[i].alpha = *entry_start++;
+ }
+ else
+ {
+ pp[i].red = png_get_uint_16(entry_start); entry_start += 2;
+ pp[i].green = png_get_uint_16(entry_start); entry_start += 2;
+ pp[i].blue = png_get_uint_16(entry_start); entry_start += 2;
+ pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2;
+ }
+ pp->frequency = png_get_uint_16(entry_start); entry_start += 2;
+ }
+#endif
+
+ /* discard all chunk data except the name and stash that */
+ new_palette.name = (png_charp)chunkdata;
+
+ png_set_sPLT(png_ptr, info_ptr, &new_palette, 1);
+
+ png_free(png_ptr, chunkdata);
+ png_free(png_ptr, new_palette.entries);
+}
+#endif /* PNG_READ_sPLT_SUPPORTED */
+
+#if defined(PNG_READ_tRNS_SUPPORTED)
+void /* PRIVATE */
+png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_byte readbuf[PNG_MAX_PALETTE_LENGTH];
+ int bit_mask;
+
+ png_debug(1, "in png_handle_tRNS\n");
+
+ /* For non-indexed color, mask off any bits in the tRNS value that
+ * exceed the bit depth. Some creators were writing extra bits there.
+ * This is not needed for indexed color. */
+ bit_mask = (1 << png_ptr->bit_depth) - 1;
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before tRNS");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid tRNS after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+ {
+ png_warning(png_ptr, "Duplicate tRNS chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ png_byte buf[2];
+
+ if (length != 2)
+ {
+ png_warning(png_ptr, "Incorrect tRNS chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, 2);
+ png_ptr->num_trans = 1;
+ png_ptr->trans_values.gray = png_get_uint_16(buf) & bit_mask;
+ }
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ png_byte buf[6];
+
+ if (length != 6)
+ {
+ png_warning(png_ptr, "Incorrect tRNS chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ png_crc_read(png_ptr, buf, (png_size_t)length);
+ png_ptr->num_trans = 1;
+ png_ptr->trans_values.red = png_get_uint_16(buf) & bit_mask;
+ png_ptr->trans_values.green = png_get_uint_16(buf + 2) & bit_mask;
+ png_ptr->trans_values.blue = png_get_uint_16(buf + 4) & bit_mask;
+ }
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (!(png_ptr->mode & PNG_HAVE_PLTE))
+ {
+ /* Should be an error, but we can cope with it. */
+ png_warning(png_ptr, "Missing PLTE before tRNS");
+ }
+ if (length > (png_uint_32)png_ptr->num_palette ||
+ length > PNG_MAX_PALETTE_LENGTH)
+ {
+ png_warning(png_ptr, "Incorrect tRNS chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ if (length == 0)
+ {
+ png_warning(png_ptr, "Zero length tRNS chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ png_crc_read(png_ptr, readbuf, (png_size_t)length);
+ png_ptr->num_trans = (png_uint_16)length;
+ }
+ else
+ {
+ png_warning(png_ptr, "tRNS chunk not allowed with alpha channel");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (png_crc_finish(png_ptr, 0))
+ {
+ png_ptr->num_trans = 0;
+ return;
+ }
+
+ png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
+ &(png_ptr->trans_values));
+}
+#endif
+
+#if defined(PNG_READ_bKGD_SUPPORTED)
+void /* PRIVATE */
+png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_size_t truelen;
+ png_byte buf[6];
+
+ png_debug(1, "in png_handle_bKGD\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before bKGD");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid bKGD after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+ !(png_ptr->mode & PNG_HAVE_PLTE))
+ {
+ png_warning(png_ptr, "Missing PLTE before bKGD");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD))
+ {
+ png_warning(png_ptr, "Duplicate bKGD chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ truelen = 1;
+ else if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
+ truelen = 6;
+ else
+ truelen = 2;
+
+ if (length != truelen)
+ {
+ png_warning(png_ptr, "Incorrect bKGD chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, truelen);
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ /* We convert the index value into RGB components so that we can allow
+ * arbitrary RGB values for background when we have transparency, and
+ * so it is easy to determine the RGB values of the background color
+ * from the info_ptr struct. */
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ png_ptr->background.index = buf[0];
+ if(info_ptr->num_palette)
+ {
+ if(buf[0] > info_ptr->num_palette)
+ {
+ png_warning(png_ptr, "Incorrect bKGD chunk index value");
+ return;
+ }
+ png_ptr->background.red =
+ (png_uint_16)png_ptr->palette[buf[0]].red;
+ png_ptr->background.green =
+ (png_uint_16)png_ptr->palette[buf[0]].green;
+ png_ptr->background.blue =
+ (png_uint_16)png_ptr->palette[buf[0]].blue;
+ }
+ }
+ else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */
+ {
+ png_ptr->background.red =
+ png_ptr->background.green =
+ png_ptr->background.blue =
+ png_ptr->background.gray = png_get_uint_16(buf);
+ }
+ else
+ {
+ png_ptr->background.red = png_get_uint_16(buf);
+ png_ptr->background.green = png_get_uint_16(buf + 2);
+ png_ptr->background.blue = png_get_uint_16(buf + 4);
+ }
+
+ png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background));
+}
+#endif
+
+#if defined(PNG_READ_hIST_SUPPORTED)
+void /* PRIVATE */
+png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ unsigned int num, i;
+ png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH];
+
+ png_debug(1, "in png_handle_hIST\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before hIST");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid hIST after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (!(png_ptr->mode & PNG_HAVE_PLTE))
+ {
+ png_warning(png_ptr, "Missing PLTE before hIST");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST))
+ {
+ png_warning(png_ptr, "Duplicate hIST chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ num = length / 2 ;
+ if (num != (unsigned int) png_ptr->num_palette || num >
+ (unsigned int) PNG_MAX_PALETTE_LENGTH)
+ {
+ png_warning(png_ptr, "Incorrect hIST chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ for (i = 0; i < num; i++)
+ {
+ png_byte buf[2];
+
+ png_crc_read(png_ptr, buf, 2);
+ readbuf[i] = png_get_uint_16(buf);
+ }
+
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ png_set_hIST(png_ptr, info_ptr, readbuf);
+}
+#endif
+
+#if defined(PNG_READ_pHYs_SUPPORTED)
+void /* PRIVATE */
+png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_byte buf[9];
+ png_uint_32 res_x, res_y;
+ int unit_type;
+
+ png_debug(1, "in png_handle_pHYs\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before pHYs");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid pHYs after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+ {
+ png_warning(png_ptr, "Duplicate pHYs chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (length != 9)
+ {
+ png_warning(png_ptr, "Incorrect pHYs chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, 9);
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ res_x = png_get_uint_32(buf);
+ res_y = png_get_uint_32(buf + 4);
+ unit_type = buf[8];
+ png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type);
+}
+#endif
+
+#if defined(PNG_READ_oFFs_SUPPORTED)
+void /* PRIVATE */
+png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_byte buf[9];
+ png_int_32 offset_x, offset_y;
+ int unit_type;
+
+ png_debug(1, "in png_handle_oFFs\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before oFFs");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid oFFs after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+ {
+ png_warning(png_ptr, "Duplicate oFFs chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (length != 9)
+ {
+ png_warning(png_ptr, "Incorrect oFFs chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, 9);
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ offset_x = png_get_int_32(buf);
+ offset_y = png_get_int_32(buf + 4);
+ unit_type = buf[8];
+ png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type);
+}
+#endif
+
+#if defined(PNG_READ_pCAL_SUPPORTED)
+/* read the pCAL chunk (described in the PNG Extensions document) */
+void /* PRIVATE */
+png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_charp purpose;
+ png_int_32 X0, X1;
+ png_byte type, nparams;
+ png_charp buf, units, endptr;
+ png_charpp params;
+ png_size_t slength;
+ int i;
+
+ png_debug(1, "in png_handle_pCAL\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before pCAL");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid pCAL after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL))
+ {
+ png_warning(png_ptr, "Duplicate pCAL chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_debug1(2, "Allocating and reading pCAL chunk data (%lu bytes)\n",
+ length + 1);
+ purpose = (png_charp)png_malloc_warn(png_ptr, length + 1);
+ if (purpose == NULL)
+ {
+ png_warning(png_ptr, "No memory for pCAL purpose.");
+ return;
+ }
+ slength = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)purpose, slength);
+
+ if (png_crc_finish(png_ptr, 0))
+ {
+ png_free(png_ptr, purpose);
+ return;
+ }
+
+ purpose[slength] = 0x00; /* null terminate the last string */
+
+ png_debug(3, "Finding end of pCAL purpose string\n");
+ for (buf = purpose; *buf; buf++)
+ /* empty loop */ ;
+
+ endptr = purpose + slength;
+
+ /* We need to have at least 12 bytes after the purpose string
+ in order to get the parameter information. */
+ if (endptr <= buf + 12)
+ {
+ png_warning(png_ptr, "Invalid pCAL data");
+ png_free(png_ptr, purpose);
+ return;
+ }
+
+ png_debug(3, "Reading pCAL X0, X1, type, nparams, and units\n");
+ X0 = png_get_int_32((png_bytep)buf+1);
+ X1 = png_get_int_32((png_bytep)buf+5);
+ type = buf[9];
+ nparams = buf[10];
+ units = buf + 11;
+
+ png_debug(3, "Checking pCAL equation type and number of parameters\n");
+ /* Check that we have the right number of parameters for known
+ equation types. */
+ if ((type == PNG_EQUATION_LINEAR && nparams != 2) ||
+ (type == PNG_EQUATION_BASE_E && nparams != 3) ||
+ (type == PNG_EQUATION_ARBITRARY && nparams != 3) ||
+ (type == PNG_EQUATION_HYPERBOLIC && nparams != 4))
+ {
+ png_warning(png_ptr, "Invalid pCAL parameters for equation type");
+ png_free(png_ptr, purpose);
+ return;
+ }
+ else if (type >= PNG_EQUATION_LAST)
+ {
+ png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
+ }
+
+ for (buf = units; *buf; buf++)
+ /* Empty loop to move past the units string. */ ;
+
+ png_debug(3, "Allocating pCAL parameters array\n");
+ params = (png_charpp)png_malloc_warn(png_ptr, (png_uint_32)(nparams
+ *png_sizeof(png_charp))) ;
+ if (params == NULL)
+ {
+ png_free(png_ptr, purpose);
+ png_warning(png_ptr, "No memory for pCAL params.");
+ return;
+ }
+
+ /* Get pointers to the start of each parameter string. */
+ for (i = 0; i < (int)nparams; i++)
+ {
+ buf++; /* Skip the null string terminator from previous parameter. */
+
+ png_debug1(3, "Reading pCAL parameter %d\n", i);
+ for (params[i] = buf; buf <= endptr && *buf != 0x00; buf++)
+ /* Empty loop to move past each parameter string */ ;
+
+ /* Make sure we haven't run out of data yet */
+ if (buf > endptr)
+ {
+ png_warning(png_ptr, "Invalid pCAL data");
+ png_free(png_ptr, purpose);
+ png_free(png_ptr, params);
+ return;
+ }
+ }
+
+ png_set_pCAL(png_ptr, info_ptr, purpose, X0, X1, type, nparams,
+ units, params);
+
+ png_free(png_ptr, purpose);
+ png_free(png_ptr, params);
+}
+#endif
+
+#if defined(PNG_READ_sCAL_SUPPORTED)
+/* read the sCAL chunk */
+void /* PRIVATE */
+png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_charp buffer, ep;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ double width, height;
+ png_charp vp;
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_charp swidth, sheight;
+#endif
+#endif
+ png_size_t slength;
+
+ png_debug(1, "in png_handle_sCAL\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before sCAL");
+ else if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ png_warning(png_ptr, "Invalid sCAL after IDAT");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sCAL))
+ {
+ png_warning(png_ptr, "Duplicate sCAL chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_debug1(2, "Allocating and reading sCAL chunk data (%lu bytes)\n",
+ length + 1);
+ buffer = (png_charp)png_malloc_warn(png_ptr, length + 1);
+ if (buffer == NULL)
+ {
+ png_warning(png_ptr, "Out of memory while processing sCAL chunk");
+ return;
+ }
+ slength = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)buffer, slength);
+
+ if (png_crc_finish(png_ptr, 0))
+ {
+ png_free(png_ptr, buffer);
+ return;
+ }
+
+ buffer[slength] = 0x00; /* null terminate the last string */
+
+ ep = buffer + 1; /* skip unit byte */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ width = png_strtod(png_ptr, ep, &vp);
+ if (*vp)
+ {
+ png_warning(png_ptr, "malformed width string in sCAL chunk");
+ return;
+ }
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ swidth = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);
+ if (swidth == NULL)
+ {
+ png_warning(png_ptr, "Out of memory while processing sCAL chunk width");
+ return;
+ }
+ png_memcpy(swidth, ep, (png_size_t)png_strlen(ep));
+#endif
+#endif
+
+ for (ep = buffer; *ep; ep++)
+ /* empty loop */ ;
+ ep++;
+
+ if (buffer + slength < ep)
+ {
+ png_warning(png_ptr, "Truncated sCAL chunk");
+#if defined(PNG_FIXED_POINT_SUPPORTED) && \
+ !defined(PNG_FLOATING_POINT_SUPPORTED)
+ png_free(png_ptr, swidth);
+#endif
+ png_free(png_ptr, buffer);
+ return;
+ }
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ height = png_strtod(png_ptr, ep, &vp);
+ if (*vp)
+ {
+ png_warning(png_ptr, "malformed height string in sCAL chunk");
+ return;
+ }
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ sheight = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);
+ if (swidth == NULL)
+ {
+ png_warning(png_ptr, "Out of memory while processing sCAL chunk height");
+ return;
+ }
+ png_memcpy(sheight, ep, (png_size_t)png_strlen(ep));
+#endif
+#endif
+
+ if (buffer + slength < ep
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ || width <= 0. || height <= 0.
+#endif
+ )
+ {
+ png_warning(png_ptr, "Invalid sCAL data");
+ png_free(png_ptr, buffer);
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
+ png_free(png_ptr, swidth);
+ png_free(png_ptr, sheight);
+#endif
+ return;
+ }
+
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ png_set_sCAL(png_ptr, info_ptr, buffer[0], width, height);
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_set_sCAL_s(png_ptr, info_ptr, buffer[0], swidth, sheight);
+#endif
+#endif
+
+ png_free(png_ptr, buffer);
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
+ png_free(png_ptr, swidth);
+ png_free(png_ptr, sheight);
+#endif
+}
+#endif
+
+#if defined(PNG_READ_tIME_SUPPORTED)
+void /* PRIVATE */
+png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_byte buf[7];
+ png_time mod_time;
+
+ png_debug(1, "in png_handle_tIME\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Out of place tIME chunk");
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME))
+ {
+ png_warning(png_ptr, "Duplicate tIME chunk");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ if (png_ptr->mode & PNG_HAVE_IDAT)
+ png_ptr->mode |= PNG_AFTER_IDAT;
+
+ if (length != 7)
+ {
+ png_warning(png_ptr, "Incorrect tIME chunk length");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+
+ png_crc_read(png_ptr, buf, 7);
+ if (png_crc_finish(png_ptr, 0))
+ return;
+
+ mod_time.second = buf[6];
+ mod_time.minute = buf[5];
+ mod_time.hour = buf[4];
+ mod_time.day = buf[3];
+ mod_time.month = buf[2];
+ mod_time.year = png_get_uint_16(buf);
+
+ png_set_tIME(png_ptr, info_ptr, &mod_time);
+}
+#endif
+
+#if defined(PNG_READ_tEXt_SUPPORTED)
+/* Note: this does not properly handle chunks that are > 64K under DOS */
+void /* PRIVATE */
+png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_textp text_ptr;
+ png_charp key;
+ png_charp text;
+ png_uint_32 skip = 0;
+ png_size_t slength;
+ int ret;
+
+ png_debug(1, "in png_handle_tEXt\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before tEXt");
+
+ if (png_ptr->mode & PNG_HAVE_IDAT)
+ png_ptr->mode |= PNG_AFTER_IDAT;
+
+#ifdef PNG_MAX_MALLOC_64K
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "tEXt chunk too large to fit in memory");
+ skip = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+
+ key = (png_charp)png_malloc_warn(png_ptr, length + 1);
+ if (key == NULL)
+ {
+ png_warning(png_ptr, "No memory to process text chunk.");
+ return;
+ }
+ slength = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)key, slength);
+
+ if (png_crc_finish(png_ptr, skip))
+ {
+ png_free(png_ptr, key);
+ return;
+ }
+
+ key[slength] = 0x00;
+
+ for (text = key; *text; text++)
+ /* empty loop to find end of key */ ;
+
+ if (text != key + slength)
+ text++;
+
+ text_ptr = (png_textp)png_malloc_warn(png_ptr,
+ (png_uint_32)png_sizeof(png_text));
+ if (text_ptr == NULL)
+ {
+ png_warning(png_ptr, "Not enough memory to process text chunk.");
+ png_free(png_ptr, key);
+ return;
+ }
+ text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
+ text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+ text_ptr->lang = NULL;
+ text_ptr->lang_key = NULL;
+ text_ptr->itxt_length = 0;
+#endif
+ text_ptr->text = text;
+ text_ptr->text_length = png_strlen(text);
+
+ ret=png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, key);
+ png_free(png_ptr, text_ptr);
+ if (ret)
+ png_warning(png_ptr, "Insufficient memory to process text chunk.");
+}
+#endif
+
+#if defined(PNG_READ_zTXt_SUPPORTED)
+/* note: this does not correctly handle chunks that are > 64K under DOS */
+void /* PRIVATE */
+png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_textp text_ptr;
+ png_charp chunkdata;
+ png_charp text;
+ int comp_type;
+ int ret;
+ png_size_t slength, prefix_len, data_len;
+
+ png_debug(1, "in png_handle_zTXt\n");
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before zTXt");
+
+ if (png_ptr->mode & PNG_HAVE_IDAT)
+ png_ptr->mode |= PNG_AFTER_IDAT;
+
+#ifdef PNG_MAX_MALLOC_64K
+ /* We will no doubt have problems with chunks even half this size, but
+ there is no hard and fast rule to tell us where to stop. */
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr,"zTXt chunk too large to fit in memory");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+#endif
+
+ chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
+ if (chunkdata == NULL)
+ {
+ png_warning(png_ptr,"Out of memory processing zTXt chunk.");
+ return;
+ }
+ slength = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+ if (png_crc_finish(png_ptr, 0))
+ {
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+
+ chunkdata[slength] = 0x00;
+
+ for (text = chunkdata; *text; text++)
+ /* empty loop */ ;
+
+ /* zTXt must have some text after the chunkdataword */
+ if (text >= chunkdata + slength - 2)
+ {
+ png_warning(png_ptr, "Truncated zTXt chunk");
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+ else
+ {
+ comp_type = *(++text);
+ if (comp_type != PNG_TEXT_COMPRESSION_zTXt)
+ {
+ png_warning(png_ptr, "Unknown compression type in zTXt chunk");
+ comp_type = PNG_TEXT_COMPRESSION_zTXt;
+ }
+ text++; /* skip the compression_method byte */
+ }
+ prefix_len = text - chunkdata;
+
+ chunkdata = (png_charp)png_decompress_chunk(png_ptr, comp_type, chunkdata,
+ (png_size_t)length, prefix_len, &data_len);
+
+ text_ptr = (png_textp)png_malloc_warn(png_ptr,
+ (png_uint_32)png_sizeof(png_text));
+ if (text_ptr == NULL)
+ {
+ png_warning(png_ptr,"Not enough memory to process zTXt chunk.");
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+ text_ptr->compression = comp_type;
+ text_ptr->key = chunkdata;
+#ifdef PNG_iTXt_SUPPORTED
+ text_ptr->lang = NULL;
+ text_ptr->lang_key = NULL;
+ text_ptr->itxt_length = 0;
+#endif
+ text_ptr->text = chunkdata + prefix_len;
+ text_ptr->text_length = data_len;
+
+ ret=png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, text_ptr);
+ png_free(png_ptr, chunkdata);
+ if (ret)
+ png_error(png_ptr, "Insufficient memory to store zTXt chunk.");
+}
+#endif
+
+#if defined(PNG_READ_iTXt_SUPPORTED)
+/* note: this does not correctly handle chunks that are > 64K under DOS */
+void /* PRIVATE */
+png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_textp text_ptr;
+ png_charp chunkdata;
+ png_charp key, lang, text, lang_key;
+ int comp_flag;
+ int comp_type = 0;
+ int ret;
+ png_size_t slength, prefix_len, data_len;
+
+ png_debug(1, "in png_handle_iTXt\n");
+
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))
+ png_error(png_ptr, "Missing IHDR before iTXt");
+
+ if (png_ptr->mode & PNG_HAVE_IDAT)
+ png_ptr->mode |= PNG_AFTER_IDAT;
+
+#ifdef PNG_MAX_MALLOC_64K
+ /* We will no doubt have problems with chunks even half this size, but
+ there is no hard and fast rule to tell us where to stop. */
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr,"iTXt chunk too large to fit in memory");
+ png_crc_finish(png_ptr, length);
+ return;
+ }
+#endif
+
+ chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
+ if (chunkdata == NULL)
+ {
+ png_warning(png_ptr, "No memory to process iTXt chunk.");
+ return;
+ }
+ slength = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+ if (png_crc_finish(png_ptr, 0))
+ {
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+
+ chunkdata[slength] = 0x00;
+
+ for (lang = chunkdata; *lang; lang++)
+ /* empty loop */ ;
+ lang++; /* skip NUL separator */
+
+ /* iTXt must have a language tag (possibly empty), two compression bytes,
+ translated keyword (possibly empty), and possibly some text after the
+ keyword */
+
+ if (lang >= chunkdata + slength - 3)
+ {
+ png_warning(png_ptr, "Truncated iTXt chunk");
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+ else
+ {
+ comp_flag = *lang++;
+ comp_type = *lang++;
+ }
+
+ for (lang_key = lang; *lang_key; lang_key++)
+ /* empty loop */ ;
+ lang_key++; /* skip NUL separator */
+
+ if (lang_key >= chunkdata + slength)
+ {
+ png_warning(png_ptr, "Truncated iTXt chunk");
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+
+ for (text = lang_key; *text; text++)
+ /* empty loop */ ;
+ text++; /* skip NUL separator */
+ if (text >= chunkdata + slength)
+ {
+ png_warning(png_ptr, "Malformed iTXt chunk");
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+
+ prefix_len = text - chunkdata;
+
+ key=chunkdata;
+ if (comp_flag)
+ chunkdata = png_decompress_chunk(png_ptr, comp_type, chunkdata,
+ (size_t)length, prefix_len, &data_len);
+ else
+ data_len=png_strlen(chunkdata + prefix_len);
+ text_ptr = (png_textp)png_malloc_warn(png_ptr,
+ (png_uint_32)png_sizeof(png_text));
+ if (text_ptr == NULL)
+ {
+ png_warning(png_ptr,"Not enough memory to process iTXt chunk.");
+ png_free(png_ptr, chunkdata);
+ return;
+ }
+ text_ptr->compression = (int)comp_flag + 1;
+ text_ptr->lang_key = chunkdata+(lang_key-key);
+ text_ptr->lang = chunkdata+(lang-key);
+ text_ptr->itxt_length = data_len;
+ text_ptr->text_length = 0;
+ text_ptr->key = chunkdata;
+ text_ptr->text = chunkdata + prefix_len;
+
+ ret=png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, text_ptr);
+ png_free(png_ptr, chunkdata);
+ if (ret)
+ png_error(png_ptr, "Insufficient memory to store iTXt chunk.");
+}
+#endif
+
+/* This function is called when we haven't found a handler for a
+ chunk. If there isn't a problem with the chunk itself (ie bad
+ chunk name, CRC, or a critical chunk), the chunk is silently ignored
+ -- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which
+ case it will be saved away to be written out later. */
+void /* PRIVATE */
+png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_uint_32 skip = 0;
+
+ png_debug(1, "in png_handle_unknown\n");
+
+ if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IDAT;
+#endif
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) /* not an IDAT */
+ png_ptr->mode |= PNG_AFTER_IDAT;
+ }
+
+ png_check_chunk_name(png_ptr, png_ptr->chunk_name);
+
+ if (!(png_ptr->chunk_name[0] & 0x20))
+ {
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+ if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+ PNG_HANDLE_CHUNK_ALWAYS
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+ && png_ptr->read_user_chunk_fn == NULL
+#endif
+ )
+#endif
+ png_chunk_error(png_ptr, "unknown critical chunk");
+ }
+
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+ if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) ||
+ (png_ptr->read_user_chunk_fn != NULL))
+ {
+#ifdef PNG_MAX_MALLOC_64K
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "unknown chunk too large to fit in memory");
+ skip = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+ png_strncpy((png_charp)png_ptr->unknown_chunk.name,
+ (png_charp)png_ptr->chunk_name, 4);
+ png_ptr->unknown_chunk.name[4] = '\0';
+ png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
+ png_ptr->unknown_chunk.size = (png_size_t)length;
+ png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+ if(png_ptr->read_user_chunk_fn != NULL)
+ {
+ /* callback to user unknown chunk handler */
+ int ret;
+ ret = (*(png_ptr->read_user_chunk_fn))
+ (png_ptr, &png_ptr->unknown_chunk);
+ if (ret < 0)
+ png_chunk_error(png_ptr, "error in user chunk");
+ if (ret == 0)
+ {
+ if (!(png_ptr->chunk_name[0] & 0x20))
+ if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+ PNG_HANDLE_CHUNK_ALWAYS)
+ png_chunk_error(png_ptr, "unknown critical chunk");
+ png_set_unknown_chunks(png_ptr, info_ptr,
+ &png_ptr->unknown_chunk, 1);
+ }
+ }
+#else
+ png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
+#endif
+ png_free(png_ptr, png_ptr->unknown_chunk.data);
+ png_ptr->unknown_chunk.data = NULL;
+ }
+ else
+#endif
+ skip = length;
+
+ png_crc_finish(png_ptr, skip);
+
+#if !defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+ info_ptr = info_ptr; /* quiet compiler warnings about unused info_ptr */
+#endif
+}
+
+/* This function is called to verify that a chunk name is valid.
+ This function can't have the "critical chunk check" incorporated
+ into it, since in the future we will need to be able to call user
+ functions to handle unknown critical chunks after we check that
+ the chunk name itself is valid. */
+
+#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
+
+void /* PRIVATE */
+png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name)
+{
+ png_debug(1, "in png_check_chunk_name\n");
+ if (isnonalpha(chunk_name[0]) || isnonalpha(chunk_name[1]) ||
+ isnonalpha(chunk_name[2]) || isnonalpha(chunk_name[3]))
+ {
+ png_chunk_error(png_ptr, "invalid chunk type");
+ }
+}
+
+/* Combines the row recently read in with the existing pixels in the
+ row. This routine takes care of alpha and transparency if requested.
+ This routine also handles the two methods of progressive display
+ of interlaced images, depending on the mask value.
+ The mask value describes which pixels are to be combined with
+ the row. The pattern always repeats every 8 pixels, so just 8
+ bits are needed. A one indicates the pixel is to be combined,
+ a zero indicates the pixel is to be skipped. This is in addition
+ to any alpha or transparency value associated with the pixel. If
+ you want all pixels to be combined, pass 0xff (255) in mask. */
+
+void /* PRIVATE */
+png_combine_row(png_structp png_ptr, png_bytep row, int mask)
+{
+ png_debug(1,"in png_combine_row\n");
+ if (mask == 0xff)
+ {
+ png_memcpy(row, png_ptr->row_buf + 1,
+ PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->width));
+ }
+ else
+ {
+ switch (png_ptr->row_info.pixel_depth)
+ {
+ case 1:
+ {
+ png_bytep sp = png_ptr->row_buf + 1;
+ png_bytep dp = row;
+ int s_inc, s_start, s_end;
+ int m = 0x80;
+ int shift;
+ png_uint_32 i;
+ png_uint_32 row_width = png_ptr->width;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACKSWAP)
+ {
+ s_start = 0;
+ s_end = 7;
+ s_inc = 1;
+ }
+ else
+#endif
+ {
+ s_start = 7;
+ s_end = 0;
+ s_inc = -1;
+ }
+
+ shift = s_start;
+
+ for (i = 0; i < row_width; i++)
+ {
+ if (m & mask)
+ {
+ int value;
+
+ value = (*sp >> shift) & 0x01;
+ *dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
+ *dp |= (png_byte)(value << shift);
+ }
+
+ if (shift == s_end)
+ {
+ shift = s_start;
+ sp++;
+ dp++;
+ }
+ else
+ shift += s_inc;
+
+ if (m == 1)
+ m = 0x80;
+ else
+ m >>= 1;
+ }
+ break;
+ }
+ case 2:
+ {
+ png_bytep sp = png_ptr->row_buf + 1;
+ png_bytep dp = row;
+ int s_start, s_end, s_inc;
+ int m = 0x80;
+ int shift;
+ png_uint_32 i;
+ png_uint_32 row_width = png_ptr->width;
+ int value;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACKSWAP)
+ {
+ s_start = 0;
+ s_end = 6;
+ s_inc = 2;
+ }
+ else
+#endif
+ {
+ s_start = 6;
+ s_end = 0;
+ s_inc = -2;
+ }
+
+ shift = s_start;
+
+ for (i = 0; i < row_width; i++)
+ {
+ if (m & mask)
+ {
+ value = (*sp >> shift) & 0x03;
+ *dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+ *dp |= (png_byte)(value << shift);
+ }
+
+ if (shift == s_end)
+ {
+ shift = s_start;
+ sp++;
+ dp++;
+ }
+ else
+ shift += s_inc;
+ if (m == 1)
+ m = 0x80;
+ else
+ m >>= 1;
+ }
+ break;
+ }
+ case 4:
+ {
+ png_bytep sp = png_ptr->row_buf + 1;
+ png_bytep dp = row;
+ int s_start, s_end, s_inc;
+ int m = 0x80;
+ int shift;
+ png_uint_32 i;
+ png_uint_32 row_width = png_ptr->width;
+ int value;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACKSWAP)
+ {
+ s_start = 0;
+ s_end = 4;
+ s_inc = 4;
+ }
+ else
+#endif
+ {
+ s_start = 4;
+ s_end = 0;
+ s_inc = -4;
+ }
+ shift = s_start;
+
+ for (i = 0; i < row_width; i++)
+ {
+ if (m & mask)
+ {
+ value = (*sp >> shift) & 0xf;
+ *dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+ *dp |= (png_byte)(value << shift);
+ }
+
+ if (shift == s_end)
+ {
+ shift = s_start;
+ sp++;
+ dp++;
+ }
+ else
+ shift += s_inc;
+ if (m == 1)
+ m = 0x80;
+ else
+ m >>= 1;
+ }
+ break;
+ }
+ default:
+ {
+ png_bytep sp = png_ptr->row_buf + 1;
+ png_bytep dp = row;
+ png_size_t pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+ png_uint_32 i;
+ png_uint_32 row_width = png_ptr->width;
+ png_byte m = 0x80;
+
+
+ for (i = 0; i < row_width; i++)
+ {
+ if (m & mask)
+ {
+ png_memcpy(dp, sp, pixel_bytes);
+ }
+
+ sp += pixel_bytes;
+ dp += pixel_bytes;
+
+ if (m == 1)
+ m = 0x80;
+ else
+ m >>= 1;
+ }
+ break;
+ }
+ }
+ }
+}
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+/* OLD pre-1.0.9 interface:
+void png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
+ png_uint_32 transformations)
+ */
+void /* PRIVATE */
+png_do_read_interlace(png_structp png_ptr)
+{
+ png_row_infop row_info = &(png_ptr->row_info);
+ png_bytep row = png_ptr->row_buf + 1;
+ int pass = png_ptr->pass;
+ png_uint_32 transformations = png_ptr->transformations;
+#ifdef PNG_USE_LOCAL_ARRAYS
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+ /* offset to next interlace block */
+ PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+
+ png_debug(1,"in png_do_read_interlace\n");
+ if (row != NULL && row_info != NULL)
+ {
+ png_uint_32 final_width;
+
+ final_width = row_info->width * png_pass_inc[pass];
+
+ switch (row_info->pixel_depth)
+ {
+ case 1:
+ {
+ png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3);
+ png_bytep dp = row + (png_size_t)((final_width - 1) >> 3);
+ int sshift, dshift;
+ int s_start, s_end, s_inc;
+ int jstop = png_pass_inc[pass];
+ png_byte v;
+ png_uint_32 i;
+ int j;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (transformations & PNG_PACKSWAP)
+ {
+ sshift = (int)((row_info->width + 7) & 0x07);
+ dshift = (int)((final_width + 7) & 0x07);
+ s_start = 7;
+ s_end = 0;
+ s_inc = -1;
+ }
+ else
+#endif
+ {
+ sshift = 7 - (int)((row_info->width + 7) & 0x07);
+ dshift = 7 - (int)((final_width + 7) & 0x07);
+ s_start = 0;
+ s_end = 7;
+ s_inc = 1;
+ }
+
+ for (i = 0; i < row_info->width; i++)
+ {
+ v = (png_byte)((*sp >> sshift) & 0x01);
+ for (j = 0; j < jstop; j++)
+ {
+ *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);
+ *dp |= (png_byte)(v << dshift);
+ if (dshift == s_end)
+ {
+ dshift = s_start;
+ dp--;
+ }
+ else
+ dshift += s_inc;
+ }
+ if (sshift == s_end)
+ {
+ sshift = s_start;
+ sp--;
+ }
+ else
+ sshift += s_inc;
+ }
+ break;
+ }
+ case 2:
+ {
+ png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2);
+ png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2);
+ int sshift, dshift;
+ int s_start, s_end, s_inc;
+ int jstop = png_pass_inc[pass];
+ png_uint_32 i;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (transformations & PNG_PACKSWAP)
+ {
+ sshift = (int)(((row_info->width + 3) & 0x03) << 1);
+ dshift = (int)(((final_width + 3) & 0x03) << 1);
+ s_start = 6;
+ s_end = 0;
+ s_inc = -2;
+ }
+ else
+#endif
+ {
+ sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1);
+ dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1);
+ s_start = 0;
+ s_end = 6;
+ s_inc = 2;
+ }
+
+ for (i = 0; i < row_info->width; i++)
+ {
+ png_byte v;
+ int j;
+
+ v = (png_byte)((*sp >> sshift) & 0x03);
+ for (j = 0; j < jstop; j++)
+ {
+ *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);
+ *dp |= (png_byte)(v << dshift);
+ if (dshift == s_end)
+ {
+ dshift = s_start;
+ dp--;
+ }
+ else
+ dshift += s_inc;
+ }
+ if (sshift == s_end)
+ {
+ sshift = s_start;
+ sp--;
+ }
+ else
+ sshift += s_inc;
+ }
+ break;
+ }
+ case 4:
+ {
+ png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1);
+ png_bytep dp = row + (png_size_t)((final_width - 1) >> 1);
+ int sshift, dshift;
+ int s_start, s_end, s_inc;
+ png_uint_32 i;
+ int jstop = png_pass_inc[pass];
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (transformations & PNG_PACKSWAP)
+ {
+ sshift = (int)(((row_info->width + 1) & 0x01) << 2);
+ dshift = (int)(((final_width + 1) & 0x01) << 2);
+ s_start = 4;
+ s_end = 0;
+ s_inc = -4;
+ }
+ else
+#endif
+ {
+ sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2);
+ dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2);
+ s_start = 0;
+ s_end = 4;
+ s_inc = 4;
+ }
+
+ for (i = 0; i < row_info->width; i++)
+ {
+ png_byte v = (png_byte)((*sp >> sshift) & 0xf);
+ int j;
+
+ for (j = 0; j < jstop; j++)
+ {
+ *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
+ *dp |= (png_byte)(v << dshift);
+ if (dshift == s_end)
+ {
+ dshift = s_start;
+ dp--;
+ }
+ else
+ dshift += s_inc;
+ }
+ if (sshift == s_end)
+ {
+ sshift = s_start;
+ sp--;
+ }
+ else
+ sshift += s_inc;
+ }
+ break;
+ }
+ default:
+ {
+ png_size_t pixel_bytes = (row_info->pixel_depth >> 3);
+ png_bytep sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;
+ png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
+
+ int jstop = png_pass_inc[pass];
+ png_uint_32 i;
+
+ for (i = 0; i < row_info->width; i++)
+ {
+ png_byte v[8];
+ int j;
+
+ png_memcpy(v, sp, pixel_bytes);
+ for (j = 0; j < jstop; j++)
+ {
+ png_memcpy(dp, v, pixel_bytes);
+ dp -= pixel_bytes;
+ }
+ sp -= pixel_bytes;
+ }
+ break;
+ }
+ }
+ row_info->width = final_width;
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,final_width);
+ }
+#if !defined(PNG_READ_PACKSWAP_SUPPORTED)
+ transformations = transformations; /* silence compiler warning */
+#endif
+}
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+
+void /* PRIVATE */
+png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
+ png_bytep prev_row, int filter)
+{
+ png_debug(1, "in png_read_filter_row\n");
+ png_debug2(2,"row = %lu, filter = %d\n", png_ptr->row_number, filter);
+ switch (filter)
+ {
+ case PNG_FILTER_VALUE_NONE:
+ break;
+ case PNG_FILTER_VALUE_SUB:
+ {
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+ png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+ png_bytep rp = row + bpp;
+ png_bytep lp = row;
+
+ for (i = bpp; i < istop; i++)
+ {
+ *rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
+ rp++;
+ }
+ break;
+ }
+ case PNG_FILTER_VALUE_UP:
+ {
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+ png_bytep rp = row;
+ png_bytep pp = prev_row;
+
+ for (i = 0; i < istop; i++)
+ {
+ *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+ rp++;
+ }
+ break;
+ }
+ case PNG_FILTER_VALUE_AVG:
+ {
+ png_uint_32 i;
+ png_bytep rp = row;
+ png_bytep pp = prev_row;
+ png_bytep lp = row;
+ png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+ png_uint_32 istop = row_info->rowbytes - bpp;
+
+ for (i = 0; i < bpp; i++)
+ {
+ *rp = (png_byte)(((int)(*rp) +
+ ((int)(*pp++) / 2 )) & 0xff);
+ rp++;
+ }
+
+ for (i = 0; i < istop; i++)
+ {
+ *rp = (png_byte)(((int)(*rp) +
+ (int)(*pp++ + *lp++) / 2 ) & 0xff);
+ rp++;
+ }
+ break;
+ }
+ case PNG_FILTER_VALUE_PAETH:
+ {
+ png_uint_32 i;
+ png_bytep rp = row;
+ png_bytep pp = prev_row;
+ png_bytep lp = row;
+ png_bytep cp = prev_row;
+ png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+ png_uint_32 istop=row_info->rowbytes - bpp;
+
+ for (i = 0; i < bpp; i++)
+ {
+ *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+ rp++;
+ }
+
+ for (i = 0; i < istop; i++) /* use leftover rp,pp */
+ {
+ int a, b, c, pa, pb, pc, p;
+
+ a = *lp++;
+ b = *pp++;
+ c = *cp++;
+
+ p = b - c;
+ pc = a - c;
+
+#ifdef PNG_USE_ABS
+ pa = abs(p);
+ pb = abs(pc);
+ pc = abs(p + pc);
+#else
+ pa = p < 0 ? -p : p;
+ pb = pc < 0 ? -pc : pc;
+ pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+ /*
+ if (pa <= pb && pa <= pc)
+ p = a;
+ else if (pb <= pc)
+ p = b;
+ else
+ p = c;
+ */
+
+ p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+
+ *rp = (png_byte)(((int)(*rp) + p) & 0xff);
+ rp++;
+ }
+ break;
+ }
+ default:
+ png_warning(png_ptr, "Ignoring bad adaptive filter type");
+ *row=0;
+ break;
+ }
+}
+
+void /* PRIVATE */
+png_read_finish_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+ /* start of interlace block */
+ PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+ /* offset to next interlace block */
+ PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+ /* start of interlace block in the y direction */
+ PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+ /* offset to next interlace block in the y direction */
+ PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+
+ png_debug(1, "in png_read_finish_row\n");
+ png_ptr->row_number++;
+ if (png_ptr->row_number < png_ptr->num_rows)
+ return;
+
+ if (png_ptr->interlaced)
+ {
+ png_ptr->row_number = 0;
+ png_memset_check(png_ptr, png_ptr->prev_row, 0,
+ png_ptr->rowbytes + 1);
+ do
+ {
+ png_ptr->pass++;
+ if (png_ptr->pass >= 7)
+ break;
+ png_ptr->iwidth = (png_ptr->width +
+ png_pass_inc[png_ptr->pass] - 1 -
+ png_pass_start[png_ptr->pass]) /
+ png_pass_inc[png_ptr->pass];
+
+ png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,
+ png_ptr->iwidth) + 1;
+
+ if (!(png_ptr->transformations & PNG_INTERLACE))
+ {
+ png_ptr->num_rows = (png_ptr->height +
+ png_pass_yinc[png_ptr->pass] - 1 -
+ png_pass_ystart[png_ptr->pass]) /
+ png_pass_yinc[png_ptr->pass];
+ if (!(png_ptr->num_rows))
+ continue;
+ }
+ else /* if (png_ptr->transformations & PNG_INTERLACE) */
+ break;
+ } while (png_ptr->iwidth == 0);
+
+ if (png_ptr->pass < 7)
+ return;
+ }
+
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+ {
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IDAT;
+#endif
+ char extra;
+ int ret;
+
+ png_ptr->zstream.next_out = (Byte *)&extra;
+ png_ptr->zstream.avail_out = (uInt)1;
+ for(;;)
+ {
+ if (!(png_ptr->zstream.avail_in))
+ {
+ while (!png_ptr->idat_size)
+ {
+ png_byte chunk_length[4];
+
+ png_crc_finish(png_ptr, 0);
+
+ png_read_data(png_ptr, chunk_length, 4);
+ png_ptr->idat_size = png_get_uint_31(png_ptr, chunk_length);
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ png_error(png_ptr, "Not enough image data");
+
+ }
+ png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
+ png_ptr->zstream.next_in = png_ptr->zbuf;
+ if (png_ptr->zbuf_size > png_ptr->idat_size)
+ png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
+ png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in);
+ png_ptr->idat_size -= png_ptr->zstream.avail_in;
+ }
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+ if (ret == Z_STREAM_END)
+ {
+ if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in ||
+ png_ptr->idat_size)
+ png_warning(png_ptr, "Extra compressed data");
+ png_ptr->mode |= PNG_AFTER_IDAT;
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+ break;
+ }
+ if (ret != Z_OK)
+ png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
+ "Decompression Error");
+
+ if (!(png_ptr->zstream.avail_out))
+ {
+ png_warning(png_ptr, "Extra compressed data.");
+ png_ptr->mode |= PNG_AFTER_IDAT;
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+ break;
+ }
+
+ }
+ png_ptr->zstream.avail_out = 0;
+ }
+
+ if (png_ptr->idat_size || png_ptr->zstream.avail_in)
+ png_warning(png_ptr, "Extra compression data");
+
+ inflateReset(&png_ptr->zstream);
+
+ png_ptr->mode |= PNG_AFTER_IDAT;
+}
+
+void /* PRIVATE */
+png_read_start_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+ /* start of interlace block */
+ PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+ /* offset to next interlace block */
+ PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+ /* start of interlace block in the y direction */
+ PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+ /* offset to next interlace block in the y direction */
+ PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+
+ int max_pixel_depth;
+ png_uint_32 row_bytes;
+
+ png_debug(1, "in png_read_start_row\n");
+ png_ptr->zstream.avail_in = 0;
+ png_init_read_transformations(png_ptr);
+ if (png_ptr->interlaced)
+ {
+ if (!(png_ptr->transformations & PNG_INTERLACE))
+ png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
+ png_pass_ystart[0]) / png_pass_yinc[0];
+ else
+ png_ptr->num_rows = png_ptr->height;
+
+ png_ptr->iwidth = (png_ptr->width +
+ png_pass_inc[png_ptr->pass] - 1 -
+ png_pass_start[png_ptr->pass]) /
+ png_pass_inc[png_ptr->pass];
+
+ row_bytes = PNG_ROWBYTES(png_ptr->pixel_depth,png_ptr->iwidth) + 1;
+
+ png_ptr->irowbytes = (png_size_t)row_bytes;
+ if((png_uint_32)png_ptr->irowbytes != row_bytes)
+ png_error(png_ptr, "Rowbytes overflow in png_read_start_row");
+ }
+ else
+ {
+ png_ptr->num_rows = png_ptr->height;
+ png_ptr->iwidth = png_ptr->width;
+ png_ptr->irowbytes = png_ptr->rowbytes + 1;
+ }
+ max_pixel_depth = png_ptr->pixel_depth;
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+ if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8)
+ max_pixel_depth = 8;
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+ if (png_ptr->transformations & PNG_EXPAND)
+ {
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (png_ptr->num_trans)
+ max_pixel_depth = 32;
+ else
+ max_pixel_depth = 24;
+ }
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ if (max_pixel_depth < 8)
+ max_pixel_depth = 8;
+ if (png_ptr->num_trans)
+ max_pixel_depth *= 2;
+ }
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ if (png_ptr->num_trans)
+ {
+ max_pixel_depth *= 4;
+ max_pixel_depth /= 3;
+ }
+ }
+ }
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+ if (png_ptr->transformations & (PNG_FILLER))
+ {
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ max_pixel_depth = 32;
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ if (max_pixel_depth <= 8)
+ max_pixel_depth = 16;
+ else
+ max_pixel_depth = 32;
+ }
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ if (max_pixel_depth <= 32)
+ max_pixel_depth = 32;
+ else
+ max_pixel_depth = 64;
+ }
+ }
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+ if (png_ptr->transformations & PNG_GRAY_TO_RGB)
+ {
+ if (
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+ (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) ||
+#endif
+#if defined(PNG_READ_FILLER_SUPPORTED)
+ (png_ptr->transformations & (PNG_FILLER)) ||
+#endif
+ png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ {
+ if (max_pixel_depth <= 16)
+ max_pixel_depth = 32;
+ else
+ max_pixel_depth = 64;
+ }
+ else
+ {
+ if (max_pixel_depth <= 8)
+ {
+ if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ max_pixel_depth = 32;
+ else
+ max_pixel_depth = 24;
+ }
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ max_pixel_depth = 64;
+ else
+ max_pixel_depth = 48;
+ }
+ }
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) && \
+defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+ if(png_ptr->transformations & PNG_USER_TRANSFORM)
+ {
+ int user_pixel_depth=png_ptr->user_transform_depth*
+ png_ptr->user_transform_channels;
+ if(user_pixel_depth > max_pixel_depth)
+ max_pixel_depth=user_pixel_depth;
+ }
+#endif
+
+ /* align the width on the next larger 8 pixels. Mainly used
+ for interlacing */
+ row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7));
+ /* calculate the maximum bytes needed, adding a byte and a pixel
+ for safety's sake */
+ row_bytes = PNG_ROWBYTES(max_pixel_depth,row_bytes) +
+ 1 + ((max_pixel_depth + 7) >> 3);
+#ifdef PNG_MAX_MALLOC_64K
+ if (row_bytes > (png_uint_32)65536L)
+ png_error(png_ptr, "This image requires a row greater than 64KB");
+#endif
+ png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes+64);
+ png_ptr->row_buf = png_ptr->big_row_buf+32;
+
+#ifdef PNG_MAX_MALLOC_64K
+ if ((png_uint_32)png_ptr->rowbytes + 1 > (png_uint_32)65536L)
+ png_error(png_ptr, "This image requires a row greater than 64KB");
+#endif
+ if ((png_uint_32)png_ptr->rowbytes > (png_uint_32)(PNG_SIZE_MAX - 1))
+ png_error(png_ptr, "Row has too many bytes to allocate in memory.");
+ png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)(
+ png_ptr->rowbytes + 1));
+
+ png_memset_check(png_ptr, png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
+
+ png_debug1(3, "width = %lu,\n", png_ptr->width);
+ png_debug1(3, "height = %lu,\n", png_ptr->height);
+ png_debug1(3, "iwidth = %lu,\n", png_ptr->iwidth);
+ png_debug1(3, "num_rows = %lu\n", png_ptr->num_rows);
+ png_debug1(3, "rowbytes = %lu,\n", png_ptr->rowbytes);
+ png_debug1(3, "irowbytes = %lu,\n", png_ptr->irowbytes);
+
+ png_ptr->flags |= PNG_FLAG_ROW_INIT;
+}
+#endif /* PNG_READ_SUPPORTED */
diff --git a/src/libpng/pngset.c b/src/libpng/pngset.c
new file mode 100644
index 0000000..b54a111
--- /dev/null
+++ b/src/libpng/pngset.c
@@ -0,0 +1,1246 @@
+
+/* pngset.c - storage of image information into info struct
+ *
+ * Last changed in libpng 1.2.22 [October 13, 2007]
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * The functions here are used during reads to store data from the file
+ * into the info struct, and during writes to store application data
+ * into the info struct for writing into the file. This abstracts the
+ * info struct and allows us to change the structure in the future.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+
+#if defined(PNG_bKGD_SUPPORTED)
+void PNGAPI
+png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
+{
+ png_debug1(1, "in %s storage function\n", "bKGD");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ png_memcpy(&(info_ptr->background), background, png_sizeof(png_color_16));
+ info_ptr->valid |= PNG_INFO_bKGD;
+}
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
+ double white_x, double white_y, double red_x, double red_y,
+ double green_x, double green_y, double blue_x, double blue_y)
+{
+ png_debug1(1, "in %s storage function\n", "cHRM");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ if (white_x < 0.0 || white_y < 0.0 ||
+ red_x < 0.0 || red_y < 0.0 ||
+ green_x < 0.0 || green_y < 0.0 ||
+ blue_x < 0.0 || blue_y < 0.0)
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to set negative chromaticity value");
+ return;
+ }
+ if (white_x > 21474.83 || white_y > 21474.83 ||
+ red_x > 21474.83 || red_y > 21474.83 ||
+ green_x > 21474.83 || green_y > 21474.83 ||
+ blue_x > 21474.83 || blue_y > 21474.83)
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to set chromaticity value exceeding 21474.83");
+ return;
+ }
+
+ info_ptr->x_white = (float)white_x;
+ info_ptr->y_white = (float)white_y;
+ info_ptr->x_red = (float)red_x;
+ info_ptr->y_red = (float)red_y;
+ info_ptr->x_green = (float)green_x;
+ info_ptr->y_green = (float)green_y;
+ info_ptr->x_blue = (float)blue_x;
+ info_ptr->y_blue = (float)blue_y;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ info_ptr->int_x_white = (png_fixed_point)(white_x*100000.+0.5);
+ info_ptr->int_y_white = (png_fixed_point)(white_y*100000.+0.5);
+ info_ptr->int_x_red = (png_fixed_point)( red_x*100000.+0.5);
+ info_ptr->int_y_red = (png_fixed_point)( red_y*100000.+0.5);
+ info_ptr->int_x_green = (png_fixed_point)(green_x*100000.+0.5);
+ info_ptr->int_y_green = (png_fixed_point)(green_y*100000.+0.5);
+ info_ptr->int_x_blue = (png_fixed_point)( blue_x*100000.+0.5);
+ info_ptr->int_y_blue = (png_fixed_point)( blue_y*100000.+0.5);
+#endif
+ info_ptr->valid |= PNG_INFO_cHRM;
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
+ png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
+ png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
+ png_fixed_point blue_x, png_fixed_point blue_y)
+{
+ png_debug1(1, "in %s storage function\n", "cHRM");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ if (white_x < 0 || white_y < 0 ||
+ red_x < 0 || red_y < 0 ||
+ green_x < 0 || green_y < 0 ||
+ blue_x < 0 || blue_y < 0)
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to set negative chromaticity value");
+ return;
+ }
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ if (white_x > (double) PNG_UINT_31_MAX ||
+ white_y > (double) PNG_UINT_31_MAX ||
+ red_x > (double) PNG_UINT_31_MAX ||
+ red_y > (double) PNG_UINT_31_MAX ||
+ green_x > (double) PNG_UINT_31_MAX ||
+ green_y > (double) PNG_UINT_31_MAX ||
+ blue_x > (double) PNG_UINT_31_MAX ||
+ blue_y > (double) PNG_UINT_31_MAX)
+#else
+ if (white_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
+ white_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
+ red_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
+ red_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
+ green_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
+ green_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
+ blue_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
+ blue_y > (png_fixed_point) PNG_UINT_31_MAX/100000L)
+#endif
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to set chromaticity value exceeding 21474.83");
+ return;
+ }
+ info_ptr->int_x_white = white_x;
+ info_ptr->int_y_white = white_y;
+ info_ptr->int_x_red = red_x;
+ info_ptr->int_y_red = red_y;
+ info_ptr->int_x_green = green_x;
+ info_ptr->int_y_green = green_y;
+ info_ptr->int_x_blue = blue_x;
+ info_ptr->int_y_blue = blue_y;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ info_ptr->x_white = (float)(white_x/100000.);
+ info_ptr->y_white = (float)(white_y/100000.);
+ info_ptr->x_red = (float)( red_x/100000.);
+ info_ptr->y_red = (float)( red_y/100000.);
+ info_ptr->x_green = (float)(green_x/100000.);
+ info_ptr->y_green = (float)(green_y/100000.);
+ info_ptr->x_blue = (float)( blue_x/100000.);
+ info_ptr->y_blue = (float)( blue_y/100000.);
+#endif
+ info_ptr->valid |= PNG_INFO_cHRM;
+}
+#endif
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
+{
+ double gamma;
+ png_debug1(1, "in %s storage function\n", "gAMA");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ /* Check for overflow */
+ if (file_gamma > 21474.83)
+ {
+ png_warning(png_ptr, "Limiting gamma to 21474.83");
+ gamma=21474.83;
+ }
+ else
+ gamma=file_gamma;
+ info_ptr->gamma = (float)gamma;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ info_ptr->int_gamma = (int)(gamma*100000.+.5);
+#endif
+ info_ptr->valid |= PNG_INFO_gAMA;
+ if(gamma == 0.0)
+ png_warning(png_ptr, "Setting gamma=0");
+}
+#endif
+void PNGAPI
+png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
+ int_gamma)
+{
+ png_fixed_point gamma;
+
+ png_debug1(1, "in %s storage function\n", "gAMA");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ if (int_gamma > (png_fixed_point) PNG_UINT_31_MAX)
+ {
+ png_warning(png_ptr, "Limiting gamma to 21474.83");
+ gamma=PNG_UINT_31_MAX;
+ }
+ else
+ {
+ if (int_gamma < 0)
+ {
+ png_warning(png_ptr, "Setting negative gamma to zero");
+ gamma=0;
+ }
+ else
+ gamma=int_gamma;
+ }
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ info_ptr->gamma = (float)(gamma/100000.);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ info_ptr->int_gamma = gamma;
+#endif
+ info_ptr->valid |= PNG_INFO_gAMA;
+ if(gamma == 0)
+ png_warning(png_ptr, "Setting gamma=0");
+}
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+void PNGAPI
+png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
+{
+ int i;
+
+ png_debug1(1, "in %s storage function\n", "hIST");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+ if (info_ptr->num_palette == 0 || info_ptr->num_palette
+ > PNG_MAX_PALETTE_LENGTH)
+ {
+ png_warning(png_ptr,
+ "Invalid palette size, hIST allocation skipped.");
+ return;
+ }
+
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
+#endif
+ /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in version
+ 1.2.1 */
+ png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr,
+ (png_uint_32)(PNG_MAX_PALETTE_LENGTH * png_sizeof (png_uint_16)));
+ if (png_ptr->hist == NULL)
+ {
+ png_warning(png_ptr, "Insufficient memory for hIST chunk data.");
+ return;
+ }
+
+ for (i = 0; i < info_ptr->num_palette; i++)
+ png_ptr->hist[i] = hist[i];
+ info_ptr->hist = png_ptr->hist;
+ info_ptr->valid |= PNG_INFO_hIST;
+
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_HIST;
+#else
+ png_ptr->flags |= PNG_FLAG_FREE_HIST;
+#endif
+}
+#endif
+
+void PNGAPI
+png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 width, png_uint_32 height, int bit_depth,
+ int color_type, int interlace_type, int compression_type,
+ int filter_type)
+{
+ png_debug1(1, "in %s storage function\n", "IHDR");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ /* check for width and height valid values */
+ if (width == 0 || height == 0)
+ png_error(png_ptr, "Image width or height is zero in IHDR");
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ if (width > png_ptr->user_width_max || height > png_ptr->user_height_max)
+ png_error(png_ptr, "image size exceeds user limits in IHDR");
+#else
+ if (width > PNG_USER_WIDTH_MAX || height > PNG_USER_HEIGHT_MAX)
+ png_error(png_ptr, "image size exceeds user limits in IHDR");
+#endif
+ if (width > PNG_UINT_31_MAX || height > PNG_UINT_31_MAX)
+ png_error(png_ptr, "Invalid image size in IHDR");
+ if ( width > (PNG_UINT_32_MAX
+ >> 3) /* 8-byte RGBA pixels */
+ - 64 /* bigrowbuf hack */
+ - 1 /* filter byte */
+ - 7*8 /* rounding of width to multiple of 8 pixels */
+ - 8) /* extra max_pixel_depth pad */
+ png_warning(png_ptr, "Width is too large for libpng to process pixels");
+
+ /* check other values */
+ if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
+ bit_depth != 8 && bit_depth != 16)
+ png_error(png_ptr, "Invalid bit depth in IHDR");
+
+ if (color_type < 0 || color_type == 1 ||
+ color_type == 5 || color_type > 6)
+ png_error(png_ptr, "Invalid color type in IHDR");
+
+ if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
+ ((color_type == PNG_COLOR_TYPE_RGB ||
+ color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
+ color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
+ png_error(png_ptr, "Invalid color type/bit depth combination in IHDR");
+
+ if (interlace_type >= PNG_INTERLACE_LAST)
+ png_error(png_ptr, "Unknown interlace method in IHDR");
+
+ if (compression_type != PNG_COMPRESSION_TYPE_BASE)
+ png_error(png_ptr, "Unknown compression method in IHDR");
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ /* Accept filter_method 64 (intrapixel differencing) only if
+ * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+ * 2. Libpng did not read a PNG signature (this filter_method is only
+ * used in PNG datastreams that are embedded in MNG datastreams) and
+ * 3. The application called png_permit_mng_features with a mask that
+ * included PNG_FLAG_MNG_FILTER_64 and
+ * 4. The filter_method is 64 and
+ * 5. The color_type is RGB or RGBA
+ */
+ if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
+ png_warning(png_ptr,"MNG features are not allowed in a PNG datastream");
+ if(filter_type != PNG_FILTER_TYPE_BASE)
+ {
+ if(!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+ (filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
+ ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
+ (color_type == PNG_COLOR_TYPE_RGB ||
+ color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
+ png_error(png_ptr, "Unknown filter method in IHDR");
+ if(png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
+ png_warning(png_ptr, "Invalid filter method in IHDR");
+ }
+#else
+ if(filter_type != PNG_FILTER_TYPE_BASE)
+ png_error(png_ptr, "Unknown filter method in IHDR");
+#endif
+
+ info_ptr->width = width;
+ info_ptr->height = height;
+ info_ptr->bit_depth = (png_byte)bit_depth;
+ info_ptr->color_type =(png_byte) color_type;
+ info_ptr->compression_type = (png_byte)compression_type;
+ info_ptr->filter_type = (png_byte)filter_type;
+ info_ptr->interlace_type = (png_byte)interlace_type;
+ if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ info_ptr->channels = 1;
+ else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+ info_ptr->channels = 3;
+ else
+ info_ptr->channels = 1;
+ if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+ info_ptr->channels++;
+ info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
+
+ /* check for potential overflow */
+ if (width > (PNG_UINT_32_MAX
+ >> 3) /* 8-byte RGBA pixels */
+ - 64 /* bigrowbuf hack */
+ - 1 /* filter byte */
+ - 7*8 /* rounding of width to multiple of 8 pixels */
+ - 8) /* extra max_pixel_depth pad */
+ info_ptr->rowbytes = (png_size_t)0;
+ else
+ info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,width);
+}
+
+#if defined(PNG_oFFs_SUPPORTED)
+void PNGAPI
+png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
+ png_int_32 offset_x, png_int_32 offset_y, int unit_type)
+{
+ png_debug1(1, "in %s storage function\n", "oFFs");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ info_ptr->x_offset = offset_x;
+ info_ptr->y_offset = offset_y;
+ info_ptr->offset_unit_type = (png_byte)unit_type;
+ info_ptr->valid |= PNG_INFO_oFFs;
+}
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+void PNGAPI
+png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
+ png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
+ png_charp units, png_charpp params)
+{
+ png_uint_32 length;
+ int i;
+
+ png_debug1(1, "in %s storage function\n", "pCAL");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ length = png_strlen(purpose) + 1;
+ png_debug1(3, "allocating purpose for info (%lu bytes)\n", length);
+ info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
+ if (info_ptr->pcal_purpose == NULL)
+ {
+ png_warning(png_ptr, "Insufficient memory for pCAL purpose.");
+ return;
+ }
+ png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);
+
+ png_debug(3, "storing X0, X1, type, and nparams in info\n");
+ info_ptr->pcal_X0 = X0;
+ info_ptr->pcal_X1 = X1;
+ info_ptr->pcal_type = (png_byte)type;
+ info_ptr->pcal_nparams = (png_byte)nparams;
+
+ length = png_strlen(units) + 1;
+ png_debug1(3, "allocating units for info (%lu bytes)\n", length);
+ info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
+ if (info_ptr->pcal_units == NULL)
+ {
+ png_warning(png_ptr, "Insufficient memory for pCAL units.");
+ return;
+ }
+ png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);
+
+ info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
+ (png_uint_32)((nparams + 1) * png_sizeof(png_charp)));
+ if (info_ptr->pcal_params == NULL)
+ {
+ png_warning(png_ptr, "Insufficient memory for pCAL params.");
+ return;
+ }
+
+ info_ptr->pcal_params[nparams] = NULL;
+
+ for (i = 0; i < nparams; i++)
+ {
+ length = png_strlen(params[i]) + 1;
+ png_debug2(3, "allocating parameter %d for info (%lu bytes)\n", i, length);
+ info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
+ if (info_ptr->pcal_params[i] == NULL)
+ {
+ png_warning(png_ptr, "Insufficient memory for pCAL parameter.");
+ return;
+ }
+ png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
+ }
+
+ info_ptr->valid |= PNG_INFO_pCAL;
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_PCAL;
+#endif
+}
+#endif
+
+#if defined(PNG_READ_sCAL_SUPPORTED) || defined(PNG_WRITE_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL(png_structp png_ptr, png_infop info_ptr,
+ int unit, double width, double height)
+{
+ png_debug1(1, "in %s storage function\n", "sCAL");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ info_ptr->scal_unit = (png_byte)unit;
+ info_ptr->scal_pixel_width = width;
+ info_ptr->scal_pixel_height = height;
+
+ info_ptr->valid |= PNG_INFO_sCAL;
+}
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
+ int unit, png_charp swidth, png_charp sheight)
+{
+ png_uint_32 length;
+
+ png_debug1(1, "in %s storage function\n", "sCAL");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ info_ptr->scal_unit = (png_byte)unit;
+
+ length = png_strlen(swidth) + 1;
+ png_debug1(3, "allocating unit for info (%d bytes)\n", length);
+ info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, length);
+ if (info_ptr->scal_s_width == NULL)
+ {
+ png_warning(png_ptr,
+ "Memory allocation failed while processing sCAL.");
+ }
+ png_memcpy(info_ptr->scal_s_width, swidth, (png_size_t)length);
+
+ length = png_strlen(sheight) + 1;
+ png_debug1(3, "allocating unit for info (%d bytes)\n", length);
+ info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, length);
+ if (info_ptr->scal_s_height == NULL)
+ {
+ png_free (png_ptr, info_ptr->scal_s_width);
+ png_warning(png_ptr,
+ "Memory allocation failed while processing sCAL.");
+ }
+ png_memcpy(info_ptr->scal_s_height, sheight, (png_size_t)length);
+
+ info_ptr->valid |= PNG_INFO_sCAL;
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_SCAL;
+#endif
+}
+#endif
+#endif
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+void PNGAPI
+png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 res_x, png_uint_32 res_y, int unit_type)
+{
+ png_debug1(1, "in %s storage function\n", "pHYs");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ info_ptr->x_pixels_per_unit = res_x;
+ info_ptr->y_pixels_per_unit = res_y;
+ info_ptr->phys_unit_type = (png_byte)unit_type;
+ info_ptr->valid |= PNG_INFO_pHYs;
+}
+#endif
+
+void PNGAPI
+png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
+ png_colorp palette, int num_palette)
+{
+
+ png_debug1(1, "in %s storage function\n", "PLTE");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
+ {
+ if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ png_error(png_ptr, "Invalid palette length");
+ else
+ {
+ png_warning(png_ptr, "Invalid palette length");
+ return;
+ }
+ }
+
+ /*
+ * It may not actually be necessary to set png_ptr->palette here;
+ * we do it for backward compatibility with the way the png_handle_tRNS
+ * function used to do the allocation.
+ */
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
+#endif
+
+ /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
+ of num_palette entries,
+ in case of an invalid PNG file that has too-large sample values. */
+ png_ptr->palette = (png_colorp)png_malloc(png_ptr,
+ PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color));
+ png_memset(png_ptr->palette, 0, PNG_MAX_PALETTE_LENGTH *
+ png_sizeof(png_color));
+ png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof (png_color));
+ info_ptr->palette = png_ptr->palette;
+ info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
+
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_PLTE;
+#else
+ png_ptr->flags |= PNG_FLAG_FREE_PLTE;
+#endif
+
+ info_ptr->valid |= PNG_INFO_PLTE;
+}
+
+#if defined(PNG_sBIT_SUPPORTED)
+void PNGAPI
+png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
+ png_color_8p sig_bit)
+{
+ png_debug1(1, "in %s storage function\n", "sBIT");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof (png_color_8));
+ info_ptr->valid |= PNG_INFO_sBIT;
+}
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+void PNGAPI
+png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
+{
+ png_debug1(1, "in %s storage function\n", "sRGB");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ info_ptr->srgb_intent = (png_byte)intent;
+ info_ptr->valid |= PNG_INFO_sRGB;
+}
+
+void PNGAPI
+png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
+ int intent)
+{
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float file_gamma;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_fixed_point int_file_gamma;
+#endif
+#endif
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_fixed_point int_white_x, int_white_y, int_red_x, int_red_y, int_green_x,
+ int_green_y, int_blue_x, int_blue_y;
+#endif
+#endif
+ png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ png_set_sRGB(png_ptr, info_ptr, intent);
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ file_gamma = (float).45455;
+ png_set_gAMA(png_ptr, info_ptr, file_gamma);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ int_file_gamma = 45455L;
+ png_set_gAMA_fixed(png_ptr, info_ptr, int_file_gamma);
+#endif
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ int_white_x = 31270L;
+ int_white_y = 32900L;
+ int_red_x = 64000L;
+ int_red_y = 33000L;
+ int_green_x = 30000L;
+ int_green_y = 60000L;
+ int_blue_x = 15000L;
+ int_blue_y = 6000L;
+
+ png_set_cHRM_fixed(png_ptr, info_ptr,
+ int_white_x, int_white_y, int_red_x, int_red_y, int_green_x, int_green_y,
+ int_blue_x, int_blue_y);
+#endif
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ white_x = (float).3127;
+ white_y = (float).3290;
+ red_x = (float).64;
+ red_y = (float).33;
+ green_x = (float).30;
+ green_y = (float).60;
+ blue_x = (float).15;
+ blue_y = (float).06;
+
+ png_set_cHRM(png_ptr, info_ptr,
+ white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
+#endif
+#endif
+}
+#endif
+
+
+#if defined(PNG_iCCP_SUPPORTED)
+void PNGAPI
+png_set_iCCP(png_structp png_ptr, png_infop info_ptr,
+ png_charp name, int compression_type,
+ png_charp profile, png_uint_32 proflen)
+{
+ png_charp new_iccp_name;
+ png_charp new_iccp_profile;
+
+ png_debug1(1, "in %s storage function\n", "iCCP");
+ if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
+ return;
+
+ new_iccp_name = (png_charp)png_malloc_warn(png_ptr, png_strlen(name)+1);
+ if (new_iccp_name == NULL)
+ {
+ png_warning(png_ptr, "Insufficient memory to process iCCP chunk.");
+ return;
+ }
+ png_strncpy(new_iccp_name, name, png_strlen(name));
+ new_iccp_name[png_strlen(name)] = '\0';
+ new_iccp_profile = (png_charp)png_malloc_warn(png_ptr, proflen);
+ if (new_iccp_profile == NULL)
+ {
+ png_free (png_ptr, new_iccp_name);
+ png_warning(png_ptr, "Insufficient memory to process iCCP profile.");
+ return;
+ }
+ png_memcpy(new_iccp_profile, profile, (png_size_t)proflen);
+
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
+
+ info_ptr->iccp_proflen = proflen;
+ info_ptr->iccp_name = new_iccp_name;
+ info_ptr->iccp_profile = new_iccp_profile;
+ /* Compression is always zero but is here so the API and info structure
+ * does not have to change if we introduce multiple compression types */
+ info_ptr->iccp_compression = (png_byte)compression_type;
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_ICCP;
+#endif
+ info_ptr->valid |= PNG_INFO_iCCP;
+}
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+void PNGAPI
+png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
+ int num_text)
+{
+ int ret;
+ ret=png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
+ if (ret)
+ png_error(png_ptr, "Insufficient memory to store text");
+}
+
+int /* PRIVATE */
+png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
+ int num_text)
+{
+ int i;
+
+ png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
+ "text" : (png_const_charp)png_ptr->chunk_name));
+
+ if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
+ return(0);
+
+ /* Make sure we have enough space in the "text" array in info_struct
+ * to hold all of the incoming text_ptr objects.
+ */
+ if (info_ptr->num_text + num_text > info_ptr->max_text)
+ {
+ if (info_ptr->text != NULL)
+ {
+ png_textp old_text;
+ int old_max;
+
+ old_max = info_ptr->max_text;
+ info_ptr->max_text = info_ptr->num_text + num_text + 8;
+ old_text = info_ptr->text;
+ info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
+ (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+ if (info_ptr->text == NULL)
+ {
+ png_free(png_ptr, old_text);
+ return(1);
+ }
+ png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
+ png_sizeof(png_text)));
+ png_free(png_ptr, old_text);
+ }
+ else
+ {
+ info_ptr->max_text = num_text + 8;
+ info_ptr->num_text = 0;
+ info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
+ (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+ if (info_ptr->text == NULL)
+ return(1);
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_TEXT;
+#endif
+ }
+ png_debug1(3, "allocated %d entries for info_ptr->text\n",
+ info_ptr->max_text);
+ }
+ for (i = 0; i < num_text; i++)
+ {
+ png_size_t text_length,key_len;
+ png_size_t lang_len,lang_key_len;
+ png_textp textp = &(info_ptr->text[info_ptr->num_text]);
+
+ if (text_ptr[i].key == NULL)
+ continue;
+
+ key_len = png_strlen(text_ptr[i].key);
+
+ if(text_ptr[i].compression <= 0)
+ {
+ lang_len = 0;
+ lang_key_len = 0;
+ }
+ else
+#ifdef PNG_iTXt_SUPPORTED
+ {
+ /* set iTXt data */
+ if (text_ptr[i].lang != NULL)
+ lang_len = png_strlen(text_ptr[i].lang);
+ else
+ lang_len = 0;
+ if (text_ptr[i].lang_key != NULL)
+ lang_key_len = png_strlen(text_ptr[i].lang_key);
+ else
+ lang_key_len = 0;
+ }
+#else
+ {
+ png_warning(png_ptr, "iTXt chunk not supported.");
+ continue;
+ }
+#endif
+
+ if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
+ {
+ text_length = 0;
+#ifdef PNG_iTXt_SUPPORTED
+ if(text_ptr[i].compression > 0)
+ textp->compression = PNG_ITXT_COMPRESSION_NONE;
+ else
+#endif
+ textp->compression = PNG_TEXT_COMPRESSION_NONE;
+ }
+ else
+ {
+ text_length = png_strlen(text_ptr[i].text);
+ textp->compression = text_ptr[i].compression;
+ }
+
+ textp->key = (png_charp)png_malloc_warn(png_ptr,
+ (png_uint_32)(key_len + text_length + lang_len + lang_key_len + 4));
+ if (textp->key == NULL)
+ return(1);
+ png_debug2(2, "Allocated %lu bytes at %x in png_set_text\n",
+ (png_uint_32)(key_len + lang_len + lang_key_len + text_length + 4),
+ (int)textp->key);
+
+ png_memcpy(textp->key, text_ptr[i].key,
+ (png_size_t)(key_len));
+ *(textp->key+key_len) = '\0';
+#ifdef PNG_iTXt_SUPPORTED
+ if (text_ptr[i].compression > 0)
+ {
+ textp->lang=textp->key + key_len + 1;
+ png_memcpy(textp->lang, text_ptr[i].lang, lang_len);
+ *(textp->lang+lang_len) = '\0';
+ textp->lang_key=textp->lang + lang_len + 1;
+ png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
+ *(textp->lang_key+lang_key_len) = '\0';
+ textp->text=textp->lang_key + lang_key_len + 1;
+ }
+ else
+#endif
+ {
+#ifdef PNG_iTXt_SUPPORTED
+ textp->lang=NULL;
+ textp->lang_key=NULL;
+#endif
+ textp->text=textp->key + key_len + 1;
+ }
+ if(text_length)
+ png_memcpy(textp->text, text_ptr[i].text,
+ (png_size_t)(text_length));
+ *(textp->text+text_length) = '\0';
+
+#ifdef PNG_iTXt_SUPPORTED
+ if(textp->compression > 0)
+ {
+ textp->text_length = 0;
+ textp->itxt_length = text_length;
+ }
+ else
+#endif
+ {
+ textp->text_length = text_length;
+#ifdef PNG_iTXt_SUPPORTED
+ textp->itxt_length = 0;
+#endif
+ }
+ info_ptr->num_text++;
+ png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
+ }
+ return(0);
+}
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+void PNGAPI
+png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
+{
+ png_debug1(1, "in %s storage function\n", "tIME");
+ if (png_ptr == NULL || info_ptr == NULL ||
+ (png_ptr->mode & PNG_WROTE_tIME))
+ return;
+
+ png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof (png_time));
+ info_ptr->valid |= PNG_INFO_tIME;
+}
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+void PNGAPI
+png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
+ png_bytep trans, int num_trans, png_color_16p trans_values)
+{
+ png_debug1(1, "in %s storage function\n", "tRNS");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ if (trans != NULL)
+ {
+ /*
+ * It may not actually be necessary to set png_ptr->trans here;
+ * we do it for backward compatibility with the way the png_handle_tRNS
+ * function used to do the allocation.
+ */
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
+#endif
+ /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
+ png_ptr->trans = info_ptr->trans = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)PNG_MAX_PALETTE_LENGTH);
+ if (num_trans <= PNG_MAX_PALETTE_LENGTH)
+ png_memcpy(info_ptr->trans, trans, (png_size_t)num_trans);
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_TRNS;
+#else
+ png_ptr->flags |= PNG_FLAG_FREE_TRNS;
+#endif
+ }
+
+ if (trans_values != NULL)
+ {
+ png_memcpy(&(info_ptr->trans_values), trans_values,
+ png_sizeof(png_color_16));
+ if (num_trans == 0)
+ num_trans = 1;
+ }
+ info_ptr->num_trans = (png_uint_16)num_trans;
+ info_ptr->valid |= PNG_INFO_tRNS;
+}
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+void PNGAPI
+png_set_sPLT(png_structp png_ptr,
+ png_infop info_ptr, png_sPLT_tp entries, int nentries)
+{
+ png_sPLT_tp np;
+ int i;
+
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ np = (png_sPLT_tp)png_malloc_warn(png_ptr,
+ (info_ptr->splt_palettes_num + nentries) * png_sizeof(png_sPLT_t));
+ if (np == NULL)
+ {
+ png_warning(png_ptr, "No memory for sPLT palettes.");
+ return;
+ }
+
+ png_memcpy(np, info_ptr->splt_palettes,
+ info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
+ png_free(png_ptr, info_ptr->splt_palettes);
+ info_ptr->splt_palettes=NULL;
+
+ for (i = 0; i < nentries; i++)
+ {
+ png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
+ png_sPLT_tp from = entries + i;
+
+ to->name = (png_charp)png_malloc_warn(png_ptr,
+ png_strlen(from->name) + 1);
+ if (to->name == NULL)
+ {
+ png_warning(png_ptr,
+ "Out of memory while processing sPLT chunk");
+ }
+ /* TODO: use png_malloc_warn */
+ png_strncpy(to->name, from->name, png_strlen(from->name));
+ to->name[png_strlen(from->name)] = '\0';
+ to->entries = (png_sPLT_entryp)png_malloc_warn(png_ptr,
+ from->nentries * png_sizeof(png_sPLT_entry));
+ /* TODO: use png_malloc_warn */
+ png_memcpy(to->entries, from->entries,
+ from->nentries * png_sizeof(png_sPLT_entry));
+ if (to->entries == NULL)
+ {
+ png_warning(png_ptr,
+ "Out of memory while processing sPLT chunk");
+ png_free(png_ptr,to->name);
+ to->name = NULL;
+ }
+ to->nentries = from->nentries;
+ to->depth = from->depth;
+ }
+
+ info_ptr->splt_palettes = np;
+ info_ptr->splt_palettes_num += nentries;
+ info_ptr->valid |= PNG_INFO_sPLT;
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_SPLT;
+#endif
+}
+#endif /* PNG_sPLT_SUPPORTED */
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_unknown_chunks(png_structp png_ptr,
+ png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)
+{
+ png_unknown_chunkp np;
+ int i;
+
+ if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0)
+ return;
+
+ np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
+ (info_ptr->unknown_chunks_num + num_unknowns) *
+ png_sizeof(png_unknown_chunk));
+ if (np == NULL)
+ {
+ png_warning(png_ptr,
+ "Out of memory while processing unknown chunk.");
+ return;
+ }
+
+ png_memcpy(np, info_ptr->unknown_chunks,
+ info_ptr->unknown_chunks_num * png_sizeof(png_unknown_chunk));
+ png_free(png_ptr, info_ptr->unknown_chunks);
+ info_ptr->unknown_chunks=NULL;
+
+ for (i = 0; i < num_unknowns; i++)
+ {
+ png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
+ png_unknown_chunkp from = unknowns + i;
+
+ png_strncpy((png_charp)to->name, (png_charp)from->name, 4);
+ to->name[4] = '\0';
+ to->data = (png_bytep)png_malloc_warn(png_ptr, from->size);
+ if (to->data == NULL)
+ {
+ png_warning(png_ptr,
+ "Out of memory while processing unknown chunk.");
+ }
+ else
+ {
+ png_memcpy(to->data, from->data, from->size);
+ to->size = from->size;
+
+ /* note our location in the read or write sequence */
+ to->location = (png_byte)(png_ptr->mode & 0xff);
+ }
+ }
+
+ info_ptr->unknown_chunks = np;
+ info_ptr->unknown_chunks_num += num_unknowns;
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_UNKN;
+#endif
+}
+void PNGAPI
+png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr,
+ int chunk, int location)
+{
+ if(png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
+ (int)info_ptr->unknown_chunks_num)
+ info_ptr->unknown_chunks[chunk].location = (png_byte)location;
+}
+#endif
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+ defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+void PNGAPI
+png_permit_empty_plte (png_structp png_ptr, int empty_plte_permitted)
+{
+ /* This function is deprecated in favor of png_permit_mng_features()
+ and will be removed from libpng-1.3.0 */
+ png_debug(1, "in png_permit_empty_plte, DEPRECATED.\n");
+ if (png_ptr == NULL)
+ return;
+ png_ptr->mng_features_permitted = (png_byte)
+ ((png_ptr->mng_features_permitted & (~PNG_FLAG_MNG_EMPTY_PLTE)) |
+ ((empty_plte_permitted & PNG_FLAG_MNG_EMPTY_PLTE)));
+}
+#endif
+#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+png_uint_32 PNGAPI
+png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features)
+{
+ png_debug(1, "in png_permit_mng_features\n");
+ if (png_ptr == NULL)
+ return (png_uint_32)0;
+ png_ptr->mng_features_permitted =
+ (png_byte)(mng_features & PNG_ALL_MNG_FEATURES);
+ return (png_uint_32)png_ptr->mng_features_permitted;
+}
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_bytep
+ chunk_list, int num_chunks)
+{
+ png_bytep new_list, p;
+ int i, old_num_chunks;
+ if (png_ptr == NULL)
+ return;
+ if (num_chunks == 0)
+ {
+ if(keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
+ png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+ else
+ png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+
+ if(keep == PNG_HANDLE_CHUNK_ALWAYS)
+ png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+ else
+ png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+ return;
+ }
+ if (chunk_list == NULL)
+ return;
+ old_num_chunks=png_ptr->num_chunk_list;
+ new_list=(png_bytep)png_malloc(png_ptr,
+ (png_uint_32)(5*(num_chunks+old_num_chunks)));
+ if(png_ptr->chunk_list != NULL)
+ {
+ png_memcpy(new_list, png_ptr->chunk_list,
+ (png_size_t)(5*old_num_chunks));
+ png_free(png_ptr, png_ptr->chunk_list);
+ png_ptr->chunk_list=NULL;
+ }
+ png_memcpy(new_list+5*old_num_chunks, chunk_list,
+ (png_size_t)(5*num_chunks));
+ for (p=new_list+5*old_num_chunks+4, i=0; i<num_chunks; i++, p+=5)
+ *p=(png_byte)keep;
+ png_ptr->num_chunk_list=old_num_chunks+num_chunks;
+ png_ptr->chunk_list=new_list;
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_ptr->free_me |= PNG_FREE_LIST;
+#endif
+}
+#endif
+
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_read_user_chunk_fn(png_structp png_ptr, png_voidp user_chunk_ptr,
+ png_user_chunk_ptr read_user_chunk_fn)
+{
+ png_debug(1, "in png_set_read_user_chunk_fn\n");
+ if (png_ptr == NULL)
+ return;
+ png_ptr->read_user_chunk_fn = read_user_chunk_fn;
+ png_ptr->user_chunk_ptr = user_chunk_ptr;
+}
+#endif
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+void PNGAPI
+png_set_rows(png_structp png_ptr, png_infop info_ptr, png_bytepp row_pointers)
+{
+ png_debug1(1, "in %s storage function\n", "rows");
+
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ if(info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
+ info_ptr->row_pointers = row_pointers;
+ if(row_pointers)
+ info_ptr->valid |= PNG_INFO_IDAT;
+}
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+void PNGAPI
+png_set_compression_buffer_size(png_structp png_ptr, png_uint_32 size)
+{
+ if (png_ptr == NULL)
+ return;
+ if(png_ptr->zbuf)
+ png_free(png_ptr, png_ptr->zbuf);
+ png_ptr->zbuf_size = (png_size_t)size;
+ png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size);
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+}
+#endif
+
+void PNGAPI
+png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask)
+{
+ if (png_ptr && info_ptr)
+ info_ptr->valid &= ~mask;
+}
+
+
+#ifndef PNG_1_0_X
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+/* function was added to libpng 1.2.0 and should always exist by default */
+void PNGAPI
+png_set_asm_flags (png_structp png_ptr, png_uint_32 asm_flags)
+{
+/* Obsolete as of libpng-1.2.20 and will be removed from libpng-1.4.0 */
+ if (png_ptr != NULL)
+ png_ptr->asm_flags = 0;
+}
+
+/* this function was added to libpng 1.2.0 */
+void PNGAPI
+png_set_mmx_thresholds (png_structp png_ptr,
+ png_byte mmx_bitdepth_threshold,
+ png_uint_32 mmx_rowbytes_threshold)
+{
+/* Obsolete as of libpng-1.2.20 and will be removed from libpng-1.4.0 */
+ if (png_ptr == NULL)
+ return;
+}
+#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* this function was added to libpng 1.2.6 */
+void PNGAPI
+png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
+ png_uint_32 user_height_max)
+{
+ /* Images with dimensions larger than these limits will be
+ * rejected by png_set_IHDR(). To accept any PNG datastream
+ * regardless of dimensions, set both limits to 0x7ffffffL.
+ */
+ if(png_ptr == NULL) return;
+ png_ptr->user_width_max = user_width_max;
+ png_ptr->user_height_max = user_height_max;
+}
+#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+
+#endif /* ?PNG_1_0_X */
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngtrans.c b/src/libpng/pngtrans.c
new file mode 100644
index 0000000..1640095
--- /dev/null
+++ b/src/libpng/pngtrans.c
@@ -0,0 +1,662 @@
+
+/* pngtrans.c - transforms the data in a row (used by both readers and writers)
+ *
+ * Last changed in libpng 1.2.17 May 15, 2007
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* turn on BGR-to-RGB mapping */
+void PNGAPI
+png_set_bgr(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_bgr\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_BGR;
+}
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* turn on 16 bit byte swapping */
+void PNGAPI
+png_set_swap(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_swap\n");
+ if(png_ptr == NULL) return;
+ if (png_ptr->bit_depth == 16)
+ png_ptr->transformations |= PNG_SWAP_BYTES;
+}
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+/* turn on pixel packing */
+void PNGAPI
+png_set_packing(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_packing\n");
+ if(png_ptr == NULL) return;
+ if (png_ptr->bit_depth < 8)
+ {
+ png_ptr->transformations |= PNG_PACK;
+ png_ptr->usr_bit_depth = 8;
+ }
+}
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+/* turn on packed pixel swapping */
+void PNGAPI
+png_set_packswap(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_packswap\n");
+ if(png_ptr == NULL) return;
+ if (png_ptr->bit_depth < 8)
+ png_ptr->transformations |= PNG_PACKSWAP;
+}
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+void PNGAPI
+png_set_shift(png_structp png_ptr, png_color_8p true_bits)
+{
+ png_debug(1, "in png_set_shift\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_SHIFT;
+ png_ptr->shift = *true_bits;
+}
+#endif
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+ defined(PNG_WRITE_INTERLACING_SUPPORTED)
+int PNGAPI
+png_set_interlace_handling(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_interlace handling\n");
+ if (png_ptr && png_ptr->interlaced)
+ {
+ png_ptr->transformations |= PNG_INTERLACE;
+ return (7);
+ }
+
+ return (1);
+}
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte on read, or remove a filler or alpha byte on write.
+ * The filler type has changed in v0.95 to allow future 2-byte fillers
+ * for 48-bit input data, as well as to avoid problems with some compilers
+ * that don't like bytes as parameters.
+ */
+void PNGAPI
+png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc)
+{
+ png_debug(1, "in png_set_filler\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_FILLER;
+ png_ptr->filler = (png_byte)filler;
+ if (filler_loc == PNG_FILLER_AFTER)
+ png_ptr->flags |= PNG_FLAG_FILLER_AFTER;
+ else
+ png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER;
+
+ /* This should probably go in the "do_read_filler" routine.
+ * I attempted to do that in libpng-1.0.1a but that caused problems
+ * so I restored it in libpng-1.0.2a
+ */
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ png_ptr->usr_channels = 4;
+ }
+
+ /* Also I added this in libpng-1.0.2a (what happens when we expand
+ * a less-than-8-bit grayscale to GA? */
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8)
+ {
+ png_ptr->usr_channels = 2;
+ }
+}
+
+#if !defined(PNG_1_0_X)
+/* Added to libpng-1.2.7 */
+void PNGAPI
+png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc)
+{
+ png_debug(1, "in png_set_add_alpha\n");
+ if(png_ptr == NULL) return;
+ png_set_filler(png_ptr, filler, filler_loc);
+ png_ptr->transformations |= PNG_ADD_ALPHA;
+}
+#endif
+
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
+ defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+void PNGAPI
+png_set_swap_alpha(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_swap_alpha\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_SWAP_ALPHA;
+}
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
+ defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+void PNGAPI
+png_set_invert_alpha(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_invert_alpha\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_INVERT_ALPHA;
+}
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+void PNGAPI
+png_set_invert_mono(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_invert_mono\n");
+ if(png_ptr == NULL) return;
+ png_ptr->transformations |= PNG_INVERT_MONO;
+}
+
+/* invert monochrome grayscale data */
+void /* PRIVATE */
+png_do_invert(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_invert\n");
+ /* This test removed from libpng version 1.0.13 and 1.2.0:
+ * if (row_info->bit_depth == 1 &&
+ */
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row == NULL || row_info == NULL)
+ return;
+#endif
+ if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ png_bytep rp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+
+ for (i = 0; i < istop; i++)
+ {
+ *rp = (png_byte)(~(*rp));
+ rp++;
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+ row_info->bit_depth == 8)
+ {
+ png_bytep rp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+
+ for (i = 0; i < istop; i+=2)
+ {
+ *rp = (png_byte)(~(*rp));
+ rp+=2;
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+ row_info->bit_depth == 16)
+ {
+ png_bytep rp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+
+ for (i = 0; i < istop; i+=4)
+ {
+ *rp = (png_byte)(~(*rp));
+ *(rp+1) = (png_byte)(~(*(rp+1)));
+ rp+=4;
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* swaps byte order on 16 bit depth images */
+void /* PRIVATE */
+png_do_swap(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_swap\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ row_info->bit_depth == 16)
+ {
+ png_bytep rp = row;
+ png_uint_32 i;
+ png_uint_32 istop= row_info->width * row_info->channels;
+
+ for (i = 0; i < istop; i++, rp += 2)
+ {
+ png_byte t = *rp;
+ *rp = *(rp + 1);
+ *(rp + 1) = t;
+ }
+ }
+}
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+static PNG_CONST png_byte onebppswaptable[256] = {
+ 0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
+ 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
+ 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
+ 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
+ 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4,
+ 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
+ 0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC,
+ 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
+ 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
+ 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
+ 0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA,
+ 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
+ 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
+ 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
+ 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
+ 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
+ 0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1,
+ 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
+ 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9,
+ 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
+ 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
+ 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
+ 0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED,
+ 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
+ 0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
+ 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
+ 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
+ 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
+ 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7,
+ 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
+ 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF,
+ 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
+};
+
+static PNG_CONST png_byte twobppswaptable[256] = {
+ 0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0,
+ 0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0,
+ 0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4,
+ 0x24, 0x64, 0xA4, 0xE4, 0x34, 0x74, 0xB4, 0xF4,
+ 0x08, 0x48, 0x88, 0xC8, 0x18, 0x58, 0x98, 0xD8,
+ 0x28, 0x68, 0xA8, 0xE8, 0x38, 0x78, 0xB8, 0xF8,
+ 0x0C, 0x4C, 0x8C, 0xCC, 0x1C, 0x5C, 0x9C, 0xDC,
+ 0x2C, 0x6C, 0xAC, 0xEC, 0x3C, 0x7C, 0xBC, 0xFC,
+ 0x01, 0x41, 0x81, 0xC1, 0x11, 0x51, 0x91, 0xD1,
+ 0x21, 0x61, 0xA1, 0xE1, 0x31, 0x71, 0xB1, 0xF1,
+ 0x05, 0x45, 0x85, 0xC5, 0x15, 0x55, 0x95, 0xD5,
+ 0x25, 0x65, 0xA5, 0xE5, 0x35, 0x75, 0xB5, 0xF5,
+ 0x09, 0x49, 0x89, 0xC9, 0x19, 0x59, 0x99, 0xD9,
+ 0x29, 0x69, 0xA9, 0xE9, 0x39, 0x79, 0xB9, 0xF9,
+ 0x0D, 0x4D, 0x8D, 0xCD, 0x1D, 0x5D, 0x9D, 0xDD,
+ 0x2D, 0x6D, 0xAD, 0xED, 0x3D, 0x7D, 0xBD, 0xFD,
+ 0x02, 0x42, 0x82, 0xC2, 0x12, 0x52, 0x92, 0xD2,
+ 0x22, 0x62, 0xA2, 0xE2, 0x32, 0x72, 0xB2, 0xF2,
+ 0x06, 0x46, 0x86, 0xC6, 0x16, 0x56, 0x96, 0xD6,
+ 0x26, 0x66, 0xA6, 0xE6, 0x36, 0x76, 0xB6, 0xF6,
+ 0x0A, 0x4A, 0x8A, 0xCA, 0x1A, 0x5A, 0x9A, 0xDA,
+ 0x2A, 0x6A, 0xAA, 0xEA, 0x3A, 0x7A, 0xBA, 0xFA,
+ 0x0E, 0x4E, 0x8E, 0xCE, 0x1E, 0x5E, 0x9E, 0xDE,
+ 0x2E, 0x6E, 0xAE, 0xEE, 0x3E, 0x7E, 0xBE, 0xFE,
+ 0x03, 0x43, 0x83, 0xC3, 0x13, 0x53, 0x93, 0xD3,
+ 0x23, 0x63, 0xA3, 0xE3, 0x33, 0x73, 0xB3, 0xF3,
+ 0x07, 0x47, 0x87, 0xC7, 0x17, 0x57, 0x97, 0xD7,
+ 0x27, 0x67, 0xA7, 0xE7, 0x37, 0x77, 0xB7, 0xF7,
+ 0x0B, 0x4B, 0x8B, 0xCB, 0x1B, 0x5B, 0x9B, 0xDB,
+ 0x2B, 0x6B, 0xAB, 0xEB, 0x3B, 0x7B, 0xBB, 0xFB,
+ 0x0F, 0x4F, 0x8F, 0xCF, 0x1F, 0x5F, 0x9F, 0xDF,
+ 0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF
+};
+
+static PNG_CONST png_byte fourbppswaptable[256] = {
+ 0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70,
+ 0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0,
+ 0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71,
+ 0x81, 0x91, 0xA1, 0xB1, 0xC1, 0xD1, 0xE1, 0xF1,
+ 0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72,
+ 0x82, 0x92, 0xA2, 0xB2, 0xC2, 0xD2, 0xE2, 0xF2,
+ 0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73,
+ 0x83, 0x93, 0xA3, 0xB3, 0xC3, 0xD3, 0xE3, 0xF3,
+ 0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74,
+ 0x84, 0x94, 0xA4, 0xB4, 0xC4, 0xD4, 0xE4, 0xF4,
+ 0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75,
+ 0x85, 0x95, 0xA5, 0xB5, 0xC5, 0xD5, 0xE5, 0xF5,
+ 0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76,
+ 0x86, 0x96, 0xA6, 0xB6, 0xC6, 0xD6, 0xE6, 0xF6,
+ 0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77,
+ 0x87, 0x97, 0xA7, 0xB7, 0xC7, 0xD7, 0xE7, 0xF7,
+ 0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78,
+ 0x88, 0x98, 0xA8, 0xB8, 0xC8, 0xD8, 0xE8, 0xF8,
+ 0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79,
+ 0x89, 0x99, 0xA9, 0xB9, 0xC9, 0xD9, 0xE9, 0xF9,
+ 0x0A, 0x1A, 0x2A, 0x3A, 0x4A, 0x5A, 0x6A, 0x7A,
+ 0x8A, 0x9A, 0xAA, 0xBA, 0xCA, 0xDA, 0xEA, 0xFA,
+ 0x0B, 0x1B, 0x2B, 0x3B, 0x4B, 0x5B, 0x6B, 0x7B,
+ 0x8B, 0x9B, 0xAB, 0xBB, 0xCB, 0xDB, 0xEB, 0xFB,
+ 0x0C, 0x1C, 0x2C, 0x3C, 0x4C, 0x5C, 0x6C, 0x7C,
+ 0x8C, 0x9C, 0xAC, 0xBC, 0xCC, 0xDC, 0xEC, 0xFC,
+ 0x0D, 0x1D, 0x2D, 0x3D, 0x4D, 0x5D, 0x6D, 0x7D,
+ 0x8D, 0x9D, 0xAD, 0xBD, 0xCD, 0xDD, 0xED, 0xFD,
+ 0x0E, 0x1E, 0x2E, 0x3E, 0x4E, 0x5E, 0x6E, 0x7E,
+ 0x8E, 0x9E, 0xAE, 0xBE, 0xCE, 0xDE, 0xEE, 0xFE,
+ 0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F,
+ 0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF
+};
+
+/* swaps pixel packing order within bytes */
+void /* PRIVATE */
+png_do_packswap(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_packswap\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ row_info->bit_depth < 8)
+ {
+ png_bytep rp, end, table;
+
+ end = row + row_info->rowbytes;
+
+ if (row_info->bit_depth == 1)
+ table = (png_bytep)onebppswaptable;
+ else if (row_info->bit_depth == 2)
+ table = (png_bytep)twobppswaptable;
+ else if (row_info->bit_depth == 4)
+ table = (png_bytep)fourbppswaptable;
+ else
+ return;
+
+ for (rp = row; rp < end; rp++)
+ *rp = table[*rp];
+ }
+}
+#endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
+ defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+/* remove filler or alpha byte(s) */
+void /* PRIVATE */
+png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags)
+{
+ png_debug(1, "in png_do_strip_filler\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL)
+#endif
+ {
+ png_bytep sp=row;
+ png_bytep dp=row;
+ png_uint_32 row_width=row_info->width;
+ png_uint_32 i;
+
+ if ((row_info->color_type == PNG_COLOR_TYPE_RGB ||
+ (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
+ (flags & PNG_FLAG_STRIP_ALPHA))) &&
+ row_info->channels == 4)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ /* This converts from RGBX or RGBA to RGB */
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ dp+=3; sp+=4;
+ for (i = 1; i < row_width; i++)
+ {
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ sp++;
+ }
+ }
+ /* This converts from XRGB or ARGB to RGB */
+ else
+ {
+ for (i = 0; i < row_width; i++)
+ {
+ sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ }
+ }
+ row_info->pixel_depth = 24;
+ row_info->rowbytes = row_width * 3;
+ }
+ else /* if (row_info->bit_depth == 16) */
+ {
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ /* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */
+ sp += 8; dp += 6;
+ for (i = 1; i < row_width; i++)
+ {
+ /* This could be (although png_memcpy is probably slower):
+ png_memcpy(dp, sp, 6);
+ sp += 8;
+ dp += 6;
+ */
+
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ sp += 2;
+ }
+ }
+ else
+ {
+ /* This converts from XXRRGGBB or AARRGGBB to RRGGBB */
+ for (i = 0; i < row_width; i++)
+ {
+ /* This could be (although png_memcpy is probably slower):
+ png_memcpy(dp, sp, 6);
+ sp += 8;
+ dp += 6;
+ */
+
+ sp+=2;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ }
+ }
+ row_info->pixel_depth = 48;
+ row_info->rowbytes = row_width * 6;
+ }
+ row_info->channels = 3;
+ }
+ else if ((row_info->color_type == PNG_COLOR_TYPE_GRAY ||
+ (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+ (flags & PNG_FLAG_STRIP_ALPHA))) &&
+ row_info->channels == 2)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ /* This converts from GX or GA to G */
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ for (i = 0; i < row_width; i++)
+ {
+ *dp++ = *sp++;
+ sp++;
+ }
+ }
+ /* This converts from XG or AG to G */
+ else
+ {
+ for (i = 0; i < row_width; i++)
+ {
+ sp++;
+ *dp++ = *sp++;
+ }
+ }
+ row_info->pixel_depth = 8;
+ row_info->rowbytes = row_width;
+ }
+ else /* if (row_info->bit_depth == 16) */
+ {
+ if (flags & PNG_FLAG_FILLER_AFTER)
+ {
+ /* This converts from GGXX or GGAA to GG */
+ sp += 4; dp += 2;
+ for (i = 1; i < row_width; i++)
+ {
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ sp += 2;
+ }
+ }
+ else
+ {
+ /* This converts from XXGG or AAGG to GG */
+ for (i = 0; i < row_width; i++)
+ {
+ sp += 2;
+ *dp++ = *sp++;
+ *dp++ = *sp++;
+ }
+ }
+ row_info->pixel_depth = 16;
+ row_info->rowbytes = row_width * 2;
+ }
+ row_info->channels = 1;
+ }
+ if (flags & PNG_FLAG_STRIP_ALPHA)
+ row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
+ }
+}
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* swaps red and blue bytes within a pixel */
+void /* PRIVATE */
+png_do_bgr(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_bgr\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ (row_info->color_type & PNG_COLOR_MASK_COLOR))
+ {
+ png_uint_32 row_width = row_info->width;
+ if (row_info->bit_depth == 8)
+ {
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += 3)
+ {
+ png_byte save = *rp;
+ *rp = *(rp + 2);
+ *(rp + 2) = save;
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += 4)
+ {
+ png_byte save = *rp;
+ *rp = *(rp + 2);
+ *(rp + 2) = save;
+ }
+ }
+ }
+ else if (row_info->bit_depth == 16)
+ {
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += 6)
+ {
+ png_byte save = *rp;
+ *rp = *(rp + 4);
+ *(rp + 4) = save;
+ save = *(rp + 1);
+ *(rp + 1) = *(rp + 5);
+ *(rp + 5) = save;
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += 8)
+ {
+ png_byte save = *rp;
+ *rp = *(rp + 4);
+ *(rp + 4) = save;
+ save = *(rp + 1);
+ *(rp + 1) = *(rp + 5);
+ *(rp + 5) = save;
+ }
+ }
+ }
+ }
+}
+#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_LEGACY_SUPPORTED)
+void PNGAPI
+png_set_user_transform_info(png_structp png_ptr, png_voidp
+ user_transform_ptr, int user_transform_depth, int user_transform_channels)
+{
+ png_debug(1, "in png_set_user_transform_info\n");
+ if(png_ptr == NULL) return;
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+ png_ptr->user_transform_ptr = user_transform_ptr;
+ png_ptr->user_transform_depth = (png_byte)user_transform_depth;
+ png_ptr->user_transform_channels = (png_byte)user_transform_channels;
+#else
+ if(user_transform_ptr || user_transform_depth || user_transform_channels)
+ png_warning(png_ptr,
+ "This version of libpng does not support user transform info");
+#endif
+}
+#endif
+
+/* This function returns a pointer to the user_transform_ptr associated with
+ * the user transform functions. The application should free any memory
+ * associated with this pointer before png_write_destroy and png_read_destroy
+ * are called.
+ */
+png_voidp PNGAPI
+png_get_user_transform_ptr(png_structp png_ptr)
+{
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+ if (png_ptr == NULL) return (NULL);
+ return ((png_voidp)png_ptr->user_transform_ptr);
+#else
+ return (NULL);
+#endif
+}
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngvcrd.c b/src/libpng/pngvcrd.c
new file mode 100644
index 0000000..ce4233e
--- /dev/null
+++ b/src/libpng/pngvcrd.c
@@ -0,0 +1 @@
+/* pnggvrd.c was removed from libpng-1.2.20. */
diff --git a/src/libpng/pngwio.c b/src/libpng/pngwio.c
new file mode 100644
index 0000000..371a4fa
--- /dev/null
+++ b/src/libpng/pngwio.c
@@ -0,0 +1,234 @@
+
+/* pngwio.c - functions for data output
+ *
+ * Last changed in libpng 1.2.13 November 13, 2006
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2006 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all output. Users who need
+ * special handling are expected to write functions that have the same
+ * arguments as these and perform similar functions, but that possibly
+ * use different output methods. Note that you shouldn't change these
+ * functions, but rather write replacement functions and then change
+ * them at run time with png_set_write_fn(...).
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Write the data to whatever output you are using. The default routine
+ writes to a file pointer. Note that this routine sometimes gets called
+ with very small lengths, so you should implement some kind of simple
+ buffering if you are using unbuffered writes. This should never be asked
+ to write more than 64K on a 16 bit machine. */
+
+void /* PRIVATE */
+png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ if (png_ptr->write_data_fn != NULL )
+ (*(png_ptr->write_data_fn))(png_ptr, data, length);
+ else
+ png_error(png_ptr, "Call to NULL write function");
+}
+
+#if !defined(PNG_NO_STDIO)
+/* This is the function that does the actual writing of data. If you are
+ not writing to a standard C stream, you should create a replacement
+ write_data function and use it at run time with png_set_write_fn(), rather
+ than changing the library. */
+#ifndef USE_FAR_KEYWORD
+void PNGAPI
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ png_uint_32 check;
+
+ if(png_ptr == NULL) return;
+#if defined(_WIN32_WCE)
+ if ( !WriteFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+ check = 0;
+#else
+ check = fwrite(data, 1, length, (png_FILE_p)(png_ptr->io_ptr));
+#endif
+ if (check != length)
+ png_error(png_ptr, "Write Error");
+}
+#else
+/* this is the model-independent version. Since the standard I/O library
+ can't handle far buffers in the medium and small models, we have to copy
+ the data.
+*/
+
+#define NEAR_BUF_SIZE 1024
+#define MIN(a,b) (a <= b ? a : b)
+
+void PNGAPI
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ png_uint_32 check;
+ png_byte *near_data; /* Needs to be "png_byte *" instead of "png_bytep" */
+ png_FILE_p io_ptr;
+
+ if(png_ptr == NULL) return;
+ /* Check if data really is near. If so, use usual code. */
+ near_data = (png_byte *)CVT_PTR_NOCHECK(data);
+ io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
+ if ((png_bytep)near_data == data)
+ {
+#if defined(_WIN32_WCE)
+ if ( !WriteFile(io_ptr, near_data, length, &check, NULL) )
+ check = 0;
+#else
+ check = fwrite(near_data, 1, length, io_ptr);
+#endif
+ }
+ else
+ {
+ png_byte buf[NEAR_BUF_SIZE];
+ png_size_t written, remaining, err;
+ check = 0;
+ remaining = length;
+ do
+ {
+ written = MIN(NEAR_BUF_SIZE, remaining);
+ png_memcpy(buf, data, written); /* copy far buffer to near buffer */
+#if defined(_WIN32_WCE)
+ if ( !WriteFile(io_ptr, buf, written, &err, NULL) )
+ err = 0;
+#else
+ err = fwrite(buf, 1, written, io_ptr);
+#endif
+ if (err != written)
+ break;
+ else
+ check += err;
+ data += written;
+ remaining -= written;
+ }
+ while (remaining != 0);
+ }
+ if (check != length)
+ png_error(png_ptr, "Write Error");
+}
+
+#endif
+#endif
+
+/* This function is called to output any data pending writing (normally
+ to disk). After png_flush is called, there should be no data pending
+ writing in any buffers. */
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+void /* PRIVATE */
+png_flush(png_structp png_ptr)
+{
+ if (png_ptr->output_flush_fn != NULL)
+ (*(png_ptr->output_flush_fn))(png_ptr);
+}
+
+#if !defined(PNG_NO_STDIO)
+void PNGAPI
+png_default_flush(png_structp png_ptr)
+{
+#if !defined(_WIN32_WCE)
+ png_FILE_p io_ptr;
+#endif
+ if(png_ptr == NULL) return;
+#if !defined(_WIN32_WCE)
+ io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr));
+ if (io_ptr != NULL)
+ fflush(io_ptr);
+#endif
+}
+#endif
+#endif
+
+/* This function allows the application to supply new output functions for
+ libpng if standard C streams aren't being used.
+
+ This function takes as its arguments:
+ png_ptr - pointer to a png output data structure
+ io_ptr - pointer to user supplied structure containing info about
+ the output functions. May be NULL.
+ write_data_fn - pointer to a new output function that takes as its
+ arguments a pointer to a png_struct, a pointer to
+ data to be written, and a 32-bit unsigned int that is
+ the number of bytes to be written. The new write
+ function should call png_error(png_ptr, "Error msg")
+ to exit and output any fatal error messages.
+ flush_data_fn - pointer to a new flush function that takes as its
+ arguments a pointer to a png_struct. After a call to
+ the flush function, there should be no data in any buffers
+ or pending transmission. If the output method doesn't do
+ any buffering of ouput, a function prototype must still be
+ supplied although it doesn't have to do anything. If
+ PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile
+ time, output_flush_fn will be ignored, although it must be
+ supplied for compatibility. */
+void PNGAPI
+png_set_write_fn(png_structp png_ptr, png_voidp io_ptr,
+ png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)
+{
+ if(png_ptr == NULL) return;
+ png_ptr->io_ptr = io_ptr;
+
+#if !defined(PNG_NO_STDIO)
+ if (write_data_fn != NULL)
+ png_ptr->write_data_fn = write_data_fn;
+ else
+ png_ptr->write_data_fn = png_default_write_data;
+#else
+ png_ptr->write_data_fn = write_data_fn;
+#endif
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+#if !defined(PNG_NO_STDIO)
+ if (output_flush_fn != NULL)
+ png_ptr->output_flush_fn = output_flush_fn;
+ else
+ png_ptr->output_flush_fn = png_default_flush;
+#else
+ png_ptr->output_flush_fn = output_flush_fn;
+#endif
+#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+
+ /* It is an error to read while writing a png file */
+ if (png_ptr->read_data_fn != NULL)
+ {
+ png_ptr->read_data_fn = NULL;
+ png_warning(png_ptr,
+ "Attempted to set both read_data_fn and write_data_fn in");
+ png_warning(png_ptr,
+ "the same structure. Resetting read_data_fn to NULL.");
+ }
+}
+
+#if defined(USE_FAR_KEYWORD)
+#if defined(_MSC_VER)
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+{
+ void *near_ptr;
+ void FAR *far_ptr;
+ FP_OFF(near_ptr) = FP_OFF(ptr);
+ far_ptr = (void FAR *)near_ptr;
+ if(check != 0)
+ if(FP_SEG(ptr) != FP_SEG(far_ptr))
+ png_error(png_ptr,"segment lost in conversion");
+ return(near_ptr);
+}
+# else
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+{
+ void *near_ptr;
+ void FAR *far_ptr;
+ near_ptr = (void FAR *)ptr;
+ far_ptr = (void FAR *)near_ptr;
+ if(check != 0)
+ if(far_ptr != ptr)
+ png_error(png_ptr,"segment lost in conversion");
+ return(near_ptr);
+}
+# endif
+# endif
+#endif /* PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngwrite.c b/src/libpng/pngwrite.c
new file mode 100644
index 0000000..c6df1ef
--- /dev/null
+++ b/src/libpng/pngwrite.c
@@ -0,0 +1,1514 @@
+
+/* pngwrite.c - general routines to write a PNG file
+ *
+ * Last changed in libpng 1.2.15 January 5, 2007
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+/* get internal access to png.h */
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Writes all the PNG information. This is the suggested way to use the
+ * library. If you have a new chunk to add, make a function to write it,
+ * and put it in the correct location here. If you want the chunk written
+ * after the image data, put it in png_write_end(). I strongly encourage
+ * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
+ * the chunk, as that will keep the code from breaking if you want to just
+ * write a plain PNG file. If you have long comments, I suggest writing
+ * them in png_write_end(), and compressing them.
+ */
+void PNGAPI
+png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
+{
+ png_debug(1, "in png_write_info_before_PLTE\n");
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+ if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+ {
+ png_write_sig(png_ptr); /* write PNG signature */
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&(png_ptr->mng_features_permitted))
+ {
+ png_warning(png_ptr,"MNG features are not allowed in a PNG datastream");
+ png_ptr->mng_features_permitted=0;
+ }
+#endif
+ /* write IHDR information. */
+ png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
+ info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
+ info_ptr->filter_type,
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+ info_ptr->interlace_type);
+#else
+ 0);
+#endif
+ /* the rest of these check to see if the valid field has the appropriate
+ flag set, and if it does, writes the chunk. */
+#if defined(PNG_WRITE_gAMA_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_gAMA)
+ {
+# ifdef PNG_FLOATING_POINT_SUPPORTED
+ png_write_gAMA(png_ptr, info_ptr->gamma);
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma);
+# endif
+#endif
+ }
+#endif
+#if defined(PNG_WRITE_sRGB_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_sRGB)
+ png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);
+#endif
+#if defined(PNG_WRITE_iCCP_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_iCCP)
+ png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,
+ info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);
+#endif
+#if defined(PNG_WRITE_sBIT_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_sBIT)
+ png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
+#endif
+#if defined(PNG_WRITE_cHRM_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_cHRM)
+ {
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ png_write_cHRM(png_ptr,
+ info_ptr->x_white, info_ptr->y_white,
+ info_ptr->x_red, info_ptr->y_red,
+ info_ptr->x_green, info_ptr->y_green,
+ info_ptr->x_blue, info_ptr->y_blue);
+#else
+# ifdef PNG_FIXED_POINT_SUPPORTED
+ png_write_cHRM_fixed(png_ptr,
+ info_ptr->int_x_white, info_ptr->int_y_white,
+ info_ptr->int_x_red, info_ptr->int_y_red,
+ info_ptr->int_x_green, info_ptr->int_y_green,
+ info_ptr->int_x_blue, info_ptr->int_y_blue);
+# endif
+#endif
+ }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+ if (info_ptr->unknown_chunks_num)
+ {
+ png_unknown_chunk *up;
+
+ png_debug(5, "writing extra chunks\n");
+
+ for (up = info_ptr->unknown_chunks;
+ up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+ up++)
+ {
+ int keep=png_handle_as_unknown(png_ptr, up->name);
+ if (keep != PNG_HANDLE_CHUNK_NEVER &&
+ up->location && !(up->location & PNG_HAVE_PLTE) &&
+ !(up->location & PNG_HAVE_IDAT) &&
+ ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+ (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+ {
+ png_write_chunk(png_ptr, up->name, up->data, up->size);
+ }
+ }
+ }
+#endif
+ png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
+ }
+}
+
+void PNGAPI
+png_write_info(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+ int i;
+#endif
+
+ png_debug(1, "in png_write_info\n");
+
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ png_write_info_before_PLTE(png_ptr, info_ptr);
+
+ if (info_ptr->valid & PNG_INFO_PLTE)
+ png_write_PLTE(png_ptr, info_ptr->palette,
+ (png_uint_32)info_ptr->num_palette);
+ else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ png_error(png_ptr, "Valid palette required for paletted images");
+
+#if defined(PNG_WRITE_tRNS_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_tRNS)
+ {
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+ /* invert the alpha channel (in tRNS) */
+ if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
+ info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ int j;
+ for (j=0; j<(int)info_ptr->num_trans; j++)
+ info_ptr->trans[j] = (png_byte)(255 - info_ptr->trans[j]);
+ }
+#endif
+ png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),
+ info_ptr->num_trans, info_ptr->color_type);
+ }
+#endif
+#if defined(PNG_WRITE_bKGD_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_bKGD)
+ png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
+#endif
+#if defined(PNG_WRITE_hIST_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_hIST)
+ png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
+#endif
+#if defined(PNG_WRITE_oFFs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_oFFs)
+ png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
+ info_ptr->offset_unit_type);
+#endif
+#if defined(PNG_WRITE_pCAL_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_pCAL)
+ png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
+ info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
+ info_ptr->pcal_units, info_ptr->pcal_params);
+#endif
+#if defined(PNG_WRITE_sCAL_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_sCAL)
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
+ png_write_sCAL(png_ptr, (int)info_ptr->scal_unit,
+ info_ptr->scal_pixel_width, info_ptr->scal_pixel_height);
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
+ info_ptr->scal_s_width, info_ptr->scal_s_height);
+#else
+ png_warning(png_ptr,
+ "png_write_sCAL not supported; sCAL chunk not written.");
+#endif
+#endif
+#endif
+#if defined(PNG_WRITE_pHYs_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_pHYs)
+ png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
+ info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
+#endif
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_tIME)
+ {
+ png_write_tIME(png_ptr, &(info_ptr->mod_time));
+ png_ptr->mode |= PNG_WROTE_tIME;
+ }
+#endif
+#if defined(PNG_WRITE_sPLT_SUPPORTED)
+ if (info_ptr->valid & PNG_INFO_sPLT)
+ for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
+ png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
+#endif
+#if defined(PNG_WRITE_TEXT_SUPPORTED)
+ /* Check to see if we need to write text chunks */
+ for (i = 0; i < info_ptr->num_text; i++)
+ {
+ png_debug2(2, "Writing header text chunk %d, type %d\n", i,
+ info_ptr->text[i].compression);
+ /* an internationalized chunk? */
+ if (info_ptr->text[i].compression > 0)
+ {
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+ /* write international chunk */
+ png_write_iTXt(png_ptr,
+ info_ptr->text[i].compression,
+ info_ptr->text[i].key,
+ info_ptr->text[i].lang,
+ info_ptr->text[i].lang_key,
+ info_ptr->text[i].text);
+#else
+ png_warning(png_ptr, "Unable to write international text");
+#endif
+ /* Mark this chunk as written */
+ info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+ }
+ /* If we want a compressed text chunk */
+ else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
+ {
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+ /* write compressed chunk */
+ png_write_zTXt(png_ptr, info_ptr->text[i].key,
+ info_ptr->text[i].text, 0,
+ info_ptr->text[i].compression);
+#else
+ png_warning(png_ptr, "Unable to write compressed text");
+#endif
+ /* Mark this chunk as written */
+ info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
+ }
+ else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+ {
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+ /* write uncompressed chunk */
+ png_write_tEXt(png_ptr, info_ptr->text[i].key,
+ info_ptr->text[i].text,
+ 0);
+#else
+ png_warning(png_ptr, "Unable to write uncompressed text");
+#endif
+ /* Mark this chunk as written */
+ info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+ }
+ }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+ if (info_ptr->unknown_chunks_num)
+ {
+ png_unknown_chunk *up;
+
+ png_debug(5, "writing extra chunks\n");
+
+ for (up = info_ptr->unknown_chunks;
+ up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+ up++)
+ {
+ int keep=png_handle_as_unknown(png_ptr, up->name);
+ if (keep != PNG_HANDLE_CHUNK_NEVER &&
+ up->location && (up->location & PNG_HAVE_PLTE) &&
+ !(up->location & PNG_HAVE_IDAT) &&
+ ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+ (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+ {
+ png_write_chunk(png_ptr, up->name, up->data, up->size);
+ }
+ }
+ }
+#endif
+}
+
+/* Writes the end of the PNG file. If you don't want to write comments or
+ * time information, you can pass NULL for info. If you already wrote these
+ * in png_write_info(), do not write them again here. If you have long
+ * comments, I suggest writing them here, and compressing them.
+ */
+void PNGAPI
+png_write_end(png_structp png_ptr, png_infop info_ptr)
+{
+ png_debug(1, "in png_write_end\n");
+ if (png_ptr == NULL)
+ return;
+ if (!(png_ptr->mode & PNG_HAVE_IDAT))
+ png_error(png_ptr, "No IDATs written into file");
+
+ /* see if user wants us to write information chunks */
+ if (info_ptr != NULL)
+ {
+#if defined(PNG_WRITE_TEXT_SUPPORTED)
+ int i; /* local index variable */
+#endif
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+ /* check to see if user has supplied a time chunk */
+ if ((info_ptr->valid & PNG_INFO_tIME) &&
+ !(png_ptr->mode & PNG_WROTE_tIME))
+ png_write_tIME(png_ptr, &(info_ptr->mod_time));
+#endif
+#if defined(PNG_WRITE_TEXT_SUPPORTED)
+ /* loop through comment chunks */
+ for (i = 0; i < info_ptr->num_text; i++)
+ {
+ png_debug2(2, "Writing trailer text chunk %d, type %d\n", i,
+ info_ptr->text[i].compression);
+ /* an internationalized chunk? */
+ if (info_ptr->text[i].compression > 0)
+ {
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+ /* write international chunk */
+ png_write_iTXt(png_ptr,
+ info_ptr->text[i].compression,
+ info_ptr->text[i].key,
+ info_ptr->text[i].lang,
+ info_ptr->text[i].lang_key,
+ info_ptr->text[i].text);
+#else
+ png_warning(png_ptr, "Unable to write international text");
+#endif
+ /* Mark this chunk as written */
+ info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+ }
+ else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
+ {
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+ /* write compressed chunk */
+ png_write_zTXt(png_ptr, info_ptr->text[i].key,
+ info_ptr->text[i].text, 0,
+ info_ptr->text[i].compression);
+#else
+ png_warning(png_ptr, "Unable to write compressed text");
+#endif
+ /* Mark this chunk as written */
+ info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
+ }
+ else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+ {
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+ /* write uncompressed chunk */
+ png_write_tEXt(png_ptr, info_ptr->text[i].key,
+ info_ptr->text[i].text, 0);
+#else
+ png_warning(png_ptr, "Unable to write uncompressed text");
+#endif
+
+ /* Mark this chunk as written */
+ info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+ }
+ }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+ if (info_ptr->unknown_chunks_num)
+ {
+ png_unknown_chunk *up;
+
+ png_debug(5, "writing extra chunks\n");
+
+ for (up = info_ptr->unknown_chunks;
+ up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+ up++)
+ {
+ int keep=png_handle_as_unknown(png_ptr, up->name);
+ if (keep != PNG_HANDLE_CHUNK_NEVER &&
+ up->location && (up->location & PNG_AFTER_IDAT) &&
+ ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+ (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+ {
+ png_write_chunk(png_ptr, up->name, up->data, up->size);
+ }
+ }
+ }
+#endif
+ }
+
+ png_ptr->mode |= PNG_AFTER_IDAT;
+
+ /* write end of PNG file */
+ png_write_IEND(png_ptr);
+}
+
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+#if !defined(_WIN32_WCE)
+/* "time.h" functions are not supported on WindowsCE */
+void PNGAPI
+png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime)
+{
+ png_debug(1, "in png_convert_from_struct_tm\n");
+ ptime->year = (png_uint_16)(1900 + ttime->tm_year);
+ ptime->month = (png_byte)(ttime->tm_mon + 1);
+ ptime->day = (png_byte)ttime->tm_mday;
+ ptime->hour = (png_byte)ttime->tm_hour;
+ ptime->minute = (png_byte)ttime->tm_min;
+ ptime->second = (png_byte)ttime->tm_sec;
+}
+
+void PNGAPI
+png_convert_from_time_t(png_timep ptime, time_t ttime)
+{
+ struct tm *tbuf;
+
+ png_debug(1, "in png_convert_from_time_t\n");
+ tbuf = gmtime(&ttime);
+ png_convert_from_struct_tm(ptime, tbuf);
+}
+#endif
+#endif
+
+/* Initialize png_ptr structure, and allocate any memory needed */
+png_structp PNGAPI
+png_create_write_struct(png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+ return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,
+ warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
+}
+
+/* Alternate initialize png_ptr structure, and allocate any memory needed */
+png_structp PNGAPI
+png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+ png_malloc_ptr malloc_fn, png_free_ptr free_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+ png_structp png_ptr;
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+ jmp_buf jmpbuf;
+#endif
+#endif
+ int i;
+ png_debug(1, "in png_create_write_struct\n");
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
+ (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
+#else
+ png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+#endif /* PNG_USER_MEM_SUPPORTED */
+ if (png_ptr == NULL)
+ return (NULL);
+
+ /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+ png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+ if (setjmp(jmpbuf))
+#else
+ if (setjmp(png_ptr->jmpbuf))
+#endif
+ {
+ png_free(png_ptr, png_ptr->zbuf);
+ png_ptr->zbuf=NULL;
+ png_destroy_struct(png_ptr);
+ return (NULL);
+ }
+#ifdef USE_FAR_KEYWORD
+ png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#endif
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
+#endif /* PNG_USER_MEM_SUPPORTED */
+ png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
+
+ i=0;
+ do
+ {
+ if(user_png_ver[i] != png_libpng_ver[i])
+ png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+ } while (png_libpng_ver[i++]);
+
+ if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
+ {
+ /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
+ * we must recompile any applications that use any older library version.
+ * For versions after libpng 1.0, we will be compatible, so we need
+ * only check the first digit.
+ */
+ if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
+ (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
+ (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char msg[80];
+ if (user_png_ver)
+ {
+ png_snprintf(msg, 80,
+ "Application was compiled with png.h from libpng-%.20s",
+ user_png_ver);
+ png_warning(png_ptr, msg);
+ }
+ png_snprintf(msg, 80,
+ "Application is running with png.c from libpng-%.20s",
+ png_libpng_ver);
+ png_warning(png_ptr, msg);
+#endif
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "Incompatible libpng version in application and library");
+ }
+ }
+
+ /* initialize zbuf - compression buffer */
+ png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+ png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)png_ptr->zbuf_size);
+
+ png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
+ png_flush_ptr_NULL);
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
+ 1, png_doublep_NULL, png_doublep_NULL);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+/* Applications that neglect to set up their own setjmp() and then encounter
+ a png_error() will longjmp here. Since the jmpbuf is then meaningless we
+ abort instead of returning. */
+#ifdef USE_FAR_KEYWORD
+ if (setjmp(jmpbuf))
+ PNG_ABORT();
+ png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#else
+ if (setjmp(png_ptr->jmpbuf))
+ PNG_ABORT();
+#endif
+#endif
+ return (png_ptr);
+}
+
+/* Initialize png_ptr structure, and allocate any memory needed */
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+/* Deprecated. */
+#undef png_write_init
+void PNGAPI
+png_write_init(png_structp png_ptr)
+{
+ /* We only come here via pre-1.0.7-compiled applications */
+ png_write_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
+}
+
+void PNGAPI
+png_write_init_2(png_structp png_ptr, png_const_charp user_png_ver,
+ png_size_t png_struct_size, png_size_t png_info_size)
+{
+ /* We only come here via pre-1.0.12-compiled applications */
+ if(png_ptr == NULL) return;
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ if(png_sizeof(png_struct) > png_struct_size ||
+ png_sizeof(png_info) > png_info_size)
+ {
+ char msg[80];
+ png_ptr->warning_fn=NULL;
+ if (user_png_ver)
+ {
+ png_snprintf(msg, 80,
+ "Application was compiled with png.h from libpng-%.20s",
+ user_png_ver);
+ png_warning(png_ptr, msg);
+ }
+ png_snprintf(msg, 80,
+ "Application is running with png.c from libpng-%.20s",
+ png_libpng_ver);
+ png_warning(png_ptr, msg);
+ }
+#endif
+ if(png_sizeof(png_struct) > png_struct_size)
+ {
+ png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "The png struct allocated by the application for writing is too small.");
+ }
+ if(png_sizeof(png_info) > png_info_size)
+ {
+ png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "The info struct allocated by the application for writing is too small.");
+ }
+ png_write_init_3(&png_ptr, user_png_ver, png_struct_size);
+}
+#endif /* PNG_1_0_X || PNG_1_2_X */
+
+
+void PNGAPI
+png_write_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
+ png_size_t png_struct_size)
+{
+ png_structp png_ptr=*ptr_ptr;
+#ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf tmp_jmp; /* to save current jump buffer */
+#endif
+
+ int i = 0;
+
+ if (png_ptr == NULL)
+ return;
+
+ do
+ {
+ if (user_png_ver[i] != png_libpng_ver[i])
+ {
+#ifdef PNG_LEGACY_SUPPORTED
+ png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+#else
+ png_ptr->warning_fn=NULL;
+ png_warning(png_ptr,
+ "Application uses deprecated png_write_init() and should be recompiled.");
+ break;
+#endif
+ }
+ } while (png_libpng_ver[i++]);
+
+ png_debug(1, "in png_write_init_3\n");
+
+#ifdef PNG_SETJMP_SUPPORTED
+ /* save jump buffer and error functions */
+ png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+ if (png_sizeof(png_struct) > png_struct_size)
+ {
+ png_destroy_struct(png_ptr);
+ png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+ *ptr_ptr = png_ptr;
+ }
+
+ /* reset all variables to 0 */
+ png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+ /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+ png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+ /* restore jump buffer */
+ png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+
+ png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
+ png_flush_ptr_NULL);
+
+ /* initialize zbuf - compression buffer */
+ png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+ png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)png_ptr->zbuf_size);
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
+ 1, png_doublep_NULL, png_doublep_NULL);
+#endif
+}
+
+/* Write a few rows of image data. If the image is interlaced,
+ * either you will have to write the 7 sub images, or, if you
+ * have called png_set_interlace_handling(), you will have to
+ * "write" the image seven times.
+ */
+void PNGAPI
+png_write_rows(png_structp png_ptr, png_bytepp row,
+ png_uint_32 num_rows)
+{
+ png_uint_32 i; /* row counter */
+ png_bytepp rp; /* row pointer */
+
+ png_debug(1, "in png_write_rows\n");
+
+ if (png_ptr == NULL)
+ return;
+
+ /* loop through the rows */
+ for (i = 0, rp = row; i < num_rows; i++, rp++)
+ {
+ png_write_row(png_ptr, *rp);
+ }
+}
+
+/* Write the image. You only need to call this function once, even
+ * if you are writing an interlaced image.
+ */
+void PNGAPI
+png_write_image(png_structp png_ptr, png_bytepp image)
+{
+ png_uint_32 i; /* row index */
+ int pass, num_pass; /* pass variables */
+ png_bytepp rp; /* points to current row */
+
+ if (png_ptr == NULL)
+ return;
+
+ png_debug(1, "in png_write_image\n");
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+ /* intialize interlace handling. If image is not interlaced,
+ this will set pass to 1 */
+ num_pass = png_set_interlace_handling(png_ptr);
+#else
+ num_pass = 1;
+#endif
+ /* loop through passes */
+ for (pass = 0; pass < num_pass; pass++)
+ {
+ /* loop through image */
+ for (i = 0, rp = image; i < png_ptr->height; i++, rp++)
+ {
+ png_write_row(png_ptr, *rp);
+ }
+ }
+}
+
+/* called by user to write a row of image data */
+void PNGAPI
+png_write_row(png_structp png_ptr, png_bytep row)
+{
+ if (png_ptr == NULL)
+ return;
+ png_debug2(1, "in png_write_row (row %ld, pass %d)\n",
+ png_ptr->row_number, png_ptr->pass);
+
+ /* initialize transformations and other stuff if first time */
+ if (png_ptr->row_number == 0 && png_ptr->pass == 0)
+ {
+ /* make sure we wrote the header info */
+ if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+ png_error(png_ptr,
+ "png_write_info was never called before png_write_row.");
+
+ /* check for transforms that have been set but were defined out */
+#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_MONO)
+ png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
+ if (png_ptr->transformations & PNG_FILLER)
+ png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && defined(PNG_READ_PACKSWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACKSWAP)
+ png_warning(png_ptr, "PNG_WRITE_PACKSWAP_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACK)
+ png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
+ if (png_ptr->transformations & PNG_SHIFT)
+ png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
+ if (png_ptr->transformations & PNG_BGR)
+ png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_SWAP_BYTES)
+ png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined.");
+#endif
+
+ png_write_start_row(png_ptr);
+ }
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+ /* if interlaced and not interested in row, return */
+ if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+ {
+ switch (png_ptr->pass)
+ {
+ case 0:
+ if (png_ptr->row_number & 0x07)
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 1:
+ if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 2:
+ if ((png_ptr->row_number & 0x07) != 4)
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 3:
+ if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 4:
+ if ((png_ptr->row_number & 0x03) != 2)
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 5:
+ if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ break;
+ case 6:
+ if (!(png_ptr->row_number & 0x01))
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ break;
+ }
+ }
+#endif
+
+ /* set up row info for transformations */
+ png_ptr->row_info.color_type = png_ptr->color_type;
+ png_ptr->row_info.width = png_ptr->usr_width;
+ png_ptr->row_info.channels = png_ptr->usr_channels;
+ png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth;
+ png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
+ png_ptr->row_info.channels);
+
+ png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+ png_ptr->row_info.width);
+
+ png_debug1(3, "row_info->color_type = %d\n", png_ptr->row_info.color_type);
+ png_debug1(3, "row_info->width = %lu\n", png_ptr->row_info.width);
+ png_debug1(3, "row_info->channels = %d\n", png_ptr->row_info.channels);
+ png_debug1(3, "row_info->bit_depth = %d\n", png_ptr->row_info.bit_depth);
+ png_debug1(3, "row_info->pixel_depth = %d\n", png_ptr->row_info.pixel_depth);
+ png_debug1(3, "row_info->rowbytes = %lu\n", png_ptr->row_info.rowbytes);
+
+ /* Copy user's row into buffer, leaving room for filter byte. */
+ png_memcpy_check(png_ptr, png_ptr->row_buf + 1, row,
+ png_ptr->row_info.rowbytes);
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+ /* handle interlacing */
+ if (png_ptr->interlaced && png_ptr->pass < 6 &&
+ (png_ptr->transformations & PNG_INTERLACE))
+ {
+ png_do_write_interlace(&(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->pass);
+ /* this should always get caught above, but still ... */
+ if (!(png_ptr->row_info.width))
+ {
+ png_write_finish_row(png_ptr);
+ return;
+ }
+ }
+#endif
+
+ /* handle other transformations */
+ if (png_ptr->transformations)
+ png_do_write_transformations(png_ptr);
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ /* Write filter_method 64 (intrapixel differencing) only if
+ * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+ * 2. Libpng did not write a PNG signature (this filter_method is only
+ * used in PNG datastreams that are embedded in MNG datastreams) and
+ * 3. The application called png_permit_mng_features with a mask that
+ * included PNG_FLAG_MNG_FILTER_64 and
+ * 4. The filter_method is 64 and
+ * 5. The color_type is RGB or RGBA
+ */
+ if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+ (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
+ {
+ /* Intrapixel differencing */
+ png_do_write_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
+ }
+#endif
+
+ /* Find a filter if necessary, filter the row and write it out. */
+ png_write_find_filter(png_ptr, &(png_ptr->row_info));
+
+ if (png_ptr->write_row_fn != NULL)
+ (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
+}
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+/* Set the automatic flush interval or 0 to turn flushing off */
+void PNGAPI
+png_set_flush(png_structp png_ptr, int nrows)
+{
+ png_debug(1, "in png_set_flush\n");
+ if (png_ptr == NULL)
+ return;
+ png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
+}
+
+/* flush the current output buffers now */
+void PNGAPI
+png_write_flush(png_structp png_ptr)
+{
+ int wrote_IDAT;
+
+ png_debug(1, "in png_write_flush\n");
+ if (png_ptr == NULL)
+ return;
+ /* We have already written out all of the data */
+ if (png_ptr->row_number >= png_ptr->num_rows)
+ return;
+
+ do
+ {
+ int ret;
+
+ /* compress the data */
+ ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);
+ wrote_IDAT = 0;
+
+ /* check for compression errors */
+ if (ret != Z_OK)
+ {
+ if (png_ptr->zstream.msg != NULL)
+ png_error(png_ptr, png_ptr->zstream.msg);
+ else
+ png_error(png_ptr, "zlib error");
+ }
+
+ if (!(png_ptr->zstream.avail_out))
+ {
+ /* write the IDAT and reset the zlib output buffer */
+ png_write_IDAT(png_ptr, png_ptr->zbuf,
+ png_ptr->zbuf_size);
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ wrote_IDAT = 1;
+ }
+ } while(wrote_IDAT == 1);
+
+ /* If there is any data left to be output, write it into a new IDAT */
+ if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)
+ {
+ /* write the IDAT and reset the zlib output buffer */
+ png_write_IDAT(png_ptr, png_ptr->zbuf,
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ }
+ png_ptr->flush_rows = 0;
+ png_flush(png_ptr);
+}
+#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+
+/* free all memory used by the write */
+void PNGAPI
+png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
+{
+ png_structp png_ptr = NULL;
+ png_infop info_ptr = NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_free_ptr free_fn = NULL;
+ png_voidp mem_ptr = NULL;
+#endif
+
+ png_debug(1, "in png_destroy_write_struct\n");
+ if (png_ptr_ptr != NULL)
+ {
+ png_ptr = *png_ptr_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ free_fn = png_ptr->free_fn;
+ mem_ptr = png_ptr->mem_ptr;
+#endif
+ }
+
+ if (info_ptr_ptr != NULL)
+ info_ptr = *info_ptr_ptr;
+
+ if (info_ptr != NULL)
+ {
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+ if (png_ptr->num_chunk_list)
+ {
+ png_free(png_ptr, png_ptr->chunk_list);
+ png_ptr->chunk_list=NULL;
+ png_ptr->num_chunk_list=0;
+ }
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
+ (png_voidp)mem_ptr);
+#else
+ png_destroy_struct((png_voidp)info_ptr);
+#endif
+ *info_ptr_ptr = NULL;
+ }
+
+ if (png_ptr != NULL)
+ {
+ png_write_destroy(png_ptr);
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
+ (png_voidp)mem_ptr);
+#else
+ png_destroy_struct((png_voidp)png_ptr);
+#endif
+ *png_ptr_ptr = NULL;
+ }
+}
+
+
+/* Free any memory used in png_ptr struct (old method) */
+void /* PRIVATE */
+png_write_destroy(png_structp png_ptr)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf tmp_jmp; /* save jump buffer */
+#endif
+ png_error_ptr error_fn;
+ png_error_ptr warning_fn;
+ png_voidp error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_free_ptr free_fn;
+#endif
+
+ png_debug(1, "in png_write_destroy\n");
+ /* free any memory zlib uses */
+ deflateEnd(&png_ptr->zstream);
+
+ /* free our memory. png_free checks NULL for us. */
+ png_free(png_ptr, png_ptr->zbuf);
+ png_free(png_ptr, png_ptr->row_buf);
+ png_free(png_ptr, png_ptr->prev_row);
+ png_free(png_ptr, png_ptr->sub_row);
+ png_free(png_ptr, png_ptr->up_row);
+ png_free(png_ptr, png_ptr->avg_row);
+ png_free(png_ptr, png_ptr->paeth_row);
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+ png_free(png_ptr, png_ptr->time_buffer);
+#endif
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ png_free(png_ptr, png_ptr->prev_filters);
+ png_free(png_ptr, png_ptr->filter_weights);
+ png_free(png_ptr, png_ptr->inv_filter_weights);
+ png_free(png_ptr, png_ptr->filter_costs);
+ png_free(png_ptr, png_ptr->inv_filter_costs);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+ /* reset structure */
+ png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+ error_fn = png_ptr->error_fn;
+ warning_fn = png_ptr->warning_fn;
+ error_ptr = png_ptr->error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ free_fn = png_ptr->free_fn;
+#endif
+
+ png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+ png_ptr->error_fn = error_fn;
+ png_ptr->warning_fn = warning_fn;
+ png_ptr->error_ptr = error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_ptr->free_fn = free_fn;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+ png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+}
+
+/* Allow the application to select one or more row filters to use. */
+void PNGAPI
+png_set_filter(png_structp png_ptr, int method, int filters)
+{
+ png_debug(1, "in png_set_filter\n");
+ if (png_ptr == NULL)
+ return;
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+ (method == PNG_INTRAPIXEL_DIFFERENCING))
+ method = PNG_FILTER_TYPE_BASE;
+#endif
+ if (method == PNG_FILTER_TYPE_BASE)
+ {
+ switch (filters & (PNG_ALL_FILTERS | 0x07))
+ {
+#ifndef PNG_NO_WRITE_FILTER
+ case 5:
+ case 6:
+ case 7: png_warning(png_ptr, "Unknown row filter for method 0");
+#endif /* PNG_NO_WRITE_FILTER */
+ case PNG_FILTER_VALUE_NONE:
+ png_ptr->do_filter=PNG_FILTER_NONE; break;
+#ifndef PNG_NO_WRITE_FILTER
+ case PNG_FILTER_VALUE_SUB:
+ png_ptr->do_filter=PNG_FILTER_SUB; break;
+ case PNG_FILTER_VALUE_UP:
+ png_ptr->do_filter=PNG_FILTER_UP; break;
+ case PNG_FILTER_VALUE_AVG:
+ png_ptr->do_filter=PNG_FILTER_AVG; break;
+ case PNG_FILTER_VALUE_PAETH:
+ png_ptr->do_filter=PNG_FILTER_PAETH; break;
+ default: png_ptr->do_filter = (png_byte)filters; break;
+#else
+ default: png_warning(png_ptr, "Unknown row filter for method 0");
+#endif /* PNG_NO_WRITE_FILTER */
+ }
+
+ /* If we have allocated the row_buf, this means we have already started
+ * with the image and we should have allocated all of the filter buffers
+ * that have been selected. If prev_row isn't already allocated, then
+ * it is too late to start using the filters that need it, since we
+ * will be missing the data in the previous row. If an application
+ * wants to start and stop using particular filters during compression,
+ * it should start out with all of the filters, and then add and
+ * remove them after the start of compression.
+ */
+ if (png_ptr->row_buf != NULL)
+ {
+#ifndef PNG_NO_WRITE_FILTER
+ if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
+ {
+ png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
+ }
+
+ if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
+ {
+ if (png_ptr->prev_row == NULL)
+ {
+ png_warning(png_ptr, "Can't add Up filter after starting");
+ png_ptr->do_filter &= ~PNG_FILTER_UP;
+ }
+ else
+ {
+ png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
+ }
+ }
+
+ if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
+ {
+ if (png_ptr->prev_row == NULL)
+ {
+ png_warning(png_ptr, "Can't add Average filter after starting");
+ png_ptr->do_filter &= ~PNG_FILTER_AVG;
+ }
+ else
+ {
+ png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
+ }
+ }
+
+ if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
+ png_ptr->paeth_row == NULL)
+ {
+ if (png_ptr->prev_row == NULL)
+ {
+ png_warning(png_ptr, "Can't add Paeth filter after starting");
+ png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
+ }
+ else
+ {
+ png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
+ }
+ }
+
+ if (png_ptr->do_filter == PNG_NO_FILTERS)
+#endif /* PNG_NO_WRITE_FILTER */
+ png_ptr->do_filter = PNG_FILTER_NONE;
+ }
+ }
+ else
+ png_error(png_ptr, "Unknown custom filter method");
+}
+
+/* This allows us to influence the way in which libpng chooses the "best"
+ * filter for the current scanline. While the "minimum-sum-of-absolute-
+ * differences metric is relatively fast and effective, there is some
+ * question as to whether it can be improved upon by trying to keep the
+ * filtered data going to zlib more consistent, hopefully resulting in
+ * better compression.
+ */
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* GRR 970116 */
+void PNGAPI
+png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
+ int num_weights, png_doublep filter_weights,
+ png_doublep filter_costs)
+{
+ int i;
+
+ png_debug(1, "in png_set_filter_heuristics\n");
+ if (png_ptr == NULL)
+ return;
+ if (heuristic_method >= PNG_FILTER_HEURISTIC_LAST)
+ {
+ png_warning(png_ptr, "Unknown filter heuristic method");
+ return;
+ }
+
+ if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT)
+ {
+ heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
+ }
+
+ if (num_weights < 0 || filter_weights == NULL ||
+ heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
+ {
+ num_weights = 0;
+ }
+
+ png_ptr->num_prev_filters = (png_byte)num_weights;
+ png_ptr->heuristic_method = (png_byte)heuristic_method;
+
+ if (num_weights > 0)
+ {
+ if (png_ptr->prev_filters == NULL)
+ {
+ png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)(png_sizeof(png_byte) * num_weights));
+
+ /* To make sure that the weighting starts out fairly */
+ for (i = 0; i < num_weights; i++)
+ {
+ png_ptr->prev_filters[i] = 255;
+ }
+ }
+
+ if (png_ptr->filter_weights == NULL)
+ {
+ png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
+
+ png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
+ for (i = 0; i < num_weights; i++)
+ {
+ png_ptr->inv_filter_weights[i] =
+ png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
+ }
+ }
+
+ for (i = 0; i < num_weights; i++)
+ {
+ if (filter_weights[i] < 0.0)
+ {
+ png_ptr->inv_filter_weights[i] =
+ png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
+ }
+ else
+ {
+ png_ptr->inv_filter_weights[i] =
+ (png_uint_16)((double)PNG_WEIGHT_FACTOR*filter_weights[i]+0.5);
+ png_ptr->filter_weights[i] =
+ (png_uint_16)((double)PNG_WEIGHT_FACTOR/filter_weights[i]+0.5);
+ }
+ }
+ }
+
+ /* If, in the future, there are other filter methods, this would
+ * need to be based on png_ptr->filter.
+ */
+ if (png_ptr->filter_costs == NULL)
+ {
+ png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
+
+ png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
+ (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
+
+ for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
+ {
+ png_ptr->inv_filter_costs[i] =
+ png_ptr->filter_costs[i] = PNG_COST_FACTOR;
+ }
+ }
+
+ /* Here is where we set the relative costs of the different filters. We
+ * should take the desired compression level into account when setting
+ * the costs, so that Paeth, for instance, has a high relative cost at low
+ * compression levels, while it has a lower relative cost at higher
+ * compression settings. The filter types are in order of increasing
+ * relative cost, so it would be possible to do this with an algorithm.
+ */
+ for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
+ {
+ if (filter_costs == NULL || filter_costs[i] < 0.0)
+ {
+ png_ptr->inv_filter_costs[i] =
+ png_ptr->filter_costs[i] = PNG_COST_FACTOR;
+ }
+ else if (filter_costs[i] >= 1.0)
+ {
+ png_ptr->inv_filter_costs[i] =
+ (png_uint_16)((double)PNG_COST_FACTOR / filter_costs[i] + 0.5);
+ png_ptr->filter_costs[i] =
+ (png_uint_16)((double)PNG_COST_FACTOR * filter_costs[i] + 0.5);
+ }
+ }
+}
+#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+
+void PNGAPI
+png_set_compression_level(png_structp png_ptr, int level)
+{
+ png_debug(1, "in png_set_compression_level\n");
+ if (png_ptr == NULL)
+ return;
+ png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL;
+ png_ptr->zlib_level = level;
+}
+
+void PNGAPI
+png_set_compression_mem_level(png_structp png_ptr, int mem_level)
+{
+ png_debug(1, "in png_set_compression_mem_level\n");
+ if (png_ptr == NULL)
+ return;
+ png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL;
+ png_ptr->zlib_mem_level = mem_level;
+}
+
+void PNGAPI
+png_set_compression_strategy(png_structp png_ptr, int strategy)
+{
+ png_debug(1, "in png_set_compression_strategy\n");
+ if (png_ptr == NULL)
+ return;
+ png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;
+ png_ptr->zlib_strategy = strategy;
+}
+
+void PNGAPI
+png_set_compression_window_bits(png_structp png_ptr, int window_bits)
+{
+ if (png_ptr == NULL)
+ return;
+ if (window_bits > 15)
+ png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
+ else if (window_bits < 8)
+ png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
+#ifndef WBITS_8_OK
+ /* avoid libpng bug with 256-byte windows */
+ if (window_bits == 8)
+ {
+ png_warning(png_ptr, "Compression window is being reset to 512");
+ window_bits=9;
+ }
+#endif
+ png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;
+ png_ptr->zlib_window_bits = window_bits;
+}
+
+void PNGAPI
+png_set_compression_method(png_structp png_ptr, int method)
+{
+ png_debug(1, "in png_set_compression_method\n");
+ if (png_ptr == NULL)
+ return;
+ if (method != 8)
+ png_warning(png_ptr, "Only compression method 8 is supported by PNG");
+ png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD;
+ png_ptr->zlib_method = method;
+}
+
+void PNGAPI
+png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn)
+{
+ if (png_ptr == NULL)
+ return;
+ png_ptr->write_row_fn = write_row_fn;
+}
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+void PNGAPI
+png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
+ write_user_transform_fn)
+{
+ png_debug(1, "in png_set_write_user_transform_fn\n");
+ if (png_ptr == NULL)
+ return;
+ png_ptr->transformations |= PNG_USER_TRANSFORM;
+ png_ptr->write_user_transform_fn = write_user_transform_fn;
+}
+#endif
+
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+void PNGAPI
+png_write_png(png_structp png_ptr, png_infop info_ptr,
+ int transforms, voidp params)
+{
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+ /* invert the alpha channel from opacity to transparency */
+ if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+ png_set_invert_alpha(png_ptr);
+#endif
+
+ /* Write the file header information. */
+ png_write_info(png_ptr, info_ptr);
+
+ /* ------ these transformations don't touch the info structure ------- */
+
+#if defined(PNG_WRITE_INVERT_SUPPORTED)
+ /* invert monochrome pixels */
+ if (transforms & PNG_TRANSFORM_INVERT_MONO)
+ png_set_invert_mono(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+ /* Shift the pixels up to a legal bit depth and fill in
+ * as appropriate to correctly scale the image.
+ */
+ if ((transforms & PNG_TRANSFORM_SHIFT)
+ && (info_ptr->valid & PNG_INFO_sBIT))
+ png_set_shift(png_ptr, &info_ptr->sig_bit);
+#endif
+
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+ /* pack pixels into bytes */
+ if (transforms & PNG_TRANSFORM_PACKING)
+ png_set_packing(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+ /* swap location of alpha bytes from ARGB to RGBA */
+ if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+ png_set_swap_alpha(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED)
+ /* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
+ * RGB (4 channels -> 3 channels). The second parameter is not used.
+ */
+ if (transforms & PNG_TRANSFORM_STRIP_FILLER)
+ png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+#endif
+
+#if defined(PNG_WRITE_BGR_SUPPORTED)
+ /* flip BGR pixels to RGB */
+ if (transforms & PNG_TRANSFORM_BGR)
+ png_set_bgr(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_SWAP_SUPPORTED)
+ /* swap bytes of 16-bit files to most significant byte first */
+ if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+ png_set_swap(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+ /* swap bits of 1, 2, 4 bit packed pixel formats */
+ if (transforms & PNG_TRANSFORM_PACKSWAP)
+ png_set_packswap(png_ptr);
+#endif
+
+ /* ----------------------- end of transformations ------------------- */
+
+ /* write the bits */
+ if (info_ptr->valid & PNG_INFO_IDAT)
+ png_write_image(png_ptr, info_ptr->row_pointers);
+
+ /* It is REQUIRED to call this to finish writing the rest of the file */
+ png_write_end(png_ptr, info_ptr);
+
+ transforms = transforms; /* quiet compiler warnings */
+ params = params;
+}
+#endif
+#endif /* PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngwtran.c b/src/libpng/pngwtran.c
new file mode 100644
index 0000000..0372fe6
--- /dev/null
+++ b/src/libpng/pngwtran.c
@@ -0,0 +1,572 @@
+
+/* pngwtran.c - transforms the data in a row for PNG writers
+ *
+ * Last changed in libpng 1.2.9 April 14, 2006
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2006 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Transform the data according to the user's wishes. The order of
+ * transformations is significant.
+ */
+void /* PRIVATE */
+png_do_write_transformations(png_structp png_ptr)
+{
+ png_debug(1, "in png_do_write_transformations\n");
+
+ if (png_ptr == NULL)
+ return;
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+ if (png_ptr->transformations & PNG_USER_TRANSFORM)
+ if(png_ptr->write_user_transform_fn != NULL)
+ (*(png_ptr->write_user_transform_fn)) /* user write transform function */
+ (png_ptr, /* png_ptr */
+ &(png_ptr->row_info), /* row_info: */
+ /* png_uint_32 width; width of row */
+ /* png_uint_32 rowbytes; number of bytes in row */
+ /* png_byte color_type; color type of pixels */
+ /* png_byte bit_depth; bit depth of samples */
+ /* png_byte channels; number of channels (1-4) */
+ /* png_byte pixel_depth; bits per pixel (depth*channels) */
+ png_ptr->row_buf + 1); /* start of pixel data for row */
+#endif
+#if defined(PNG_WRITE_FILLER_SUPPORTED)
+ if (png_ptr->transformations & PNG_FILLER)
+ png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ png_ptr->flags);
+#endif
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACKSWAP)
+ png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+ if (png_ptr->transformations & PNG_PACK)
+ png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ (png_uint_32)png_ptr->bit_depth);
+#endif
+#if defined(PNG_WRITE_SWAP_SUPPORTED)
+ if (png_ptr->transformations & PNG_SWAP_BYTES)
+ png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+ if (png_ptr->transformations & PNG_SHIFT)
+ png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1,
+ &(png_ptr->shift));
+#endif
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+ if (png_ptr->transformations & PNG_SWAP_ALPHA)
+ png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_ALPHA)
+ png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_BGR_SUPPORTED)
+ if (png_ptr->transformations & PNG_BGR)
+ png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_INVERT_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_MONO)
+ png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+}
+
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+/* Pack pixels into bytes. Pass the true bit depth in bit_depth. The
+ * row_info bit depth should be 8 (one pixel per byte). The channels
+ * should be 1 (this only happens on grayscale and paletted images).
+ */
+void /* PRIVATE */
+png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
+{
+ png_debug(1, "in png_do_pack\n");
+ if (row_info->bit_depth == 8 &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ row_info->channels == 1)
+ {
+ switch ((int)bit_depth)
+ {
+ case 1:
+ {
+ png_bytep sp, dp;
+ int mask, v;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ sp = row;
+ dp = row;
+ mask = 0x80;
+ v = 0;
+
+ for (i = 0; i < row_width; i++)
+ {
+ if (*sp != 0)
+ v |= mask;
+ sp++;
+ if (mask > 1)
+ mask >>= 1;
+ else
+ {
+ mask = 0x80;
+ *dp = (png_byte)v;
+ dp++;
+ v = 0;
+ }
+ }
+ if (mask != 0x80)
+ *dp = (png_byte)v;
+ break;
+ }
+ case 2:
+ {
+ png_bytep sp, dp;
+ int shift, v;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ sp = row;
+ dp = row;
+ shift = 6;
+ v = 0;
+ for (i = 0; i < row_width; i++)
+ {
+ png_byte value;
+
+ value = (png_byte)(*sp & 0x03);
+ v |= (value << shift);
+ if (shift == 0)
+ {
+ shift = 6;
+ *dp = (png_byte)v;
+ dp++;
+ v = 0;
+ }
+ else
+ shift -= 2;
+ sp++;
+ }
+ if (shift != 6)
+ *dp = (png_byte)v;
+ break;
+ }
+ case 4:
+ {
+ png_bytep sp, dp;
+ int shift, v;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ sp = row;
+ dp = row;
+ shift = 4;
+ v = 0;
+ for (i = 0; i < row_width; i++)
+ {
+ png_byte value;
+
+ value = (png_byte)(*sp & 0x0f);
+ v |= (value << shift);
+
+ if (shift == 0)
+ {
+ shift = 4;
+ *dp = (png_byte)v;
+ dp++;
+ v = 0;
+ }
+ else
+ shift -= 4;
+
+ sp++;
+ }
+ if (shift != 4)
+ *dp = (png_byte)v;
+ break;
+ }
+ }
+ row_info->bit_depth = (png_byte)bit_depth;
+ row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+ row_info->width);
+ }
+}
+#endif
+
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+/* Shift pixel values to take advantage of whole range. Pass the
+ * true number of bits in bit_depth. The row should be packed
+ * according to row_info->bit_depth. Thus, if you had a row of
+ * bit depth 4, but the pixels only had values from 0 to 7, you
+ * would pass 3 as bit_depth, and this routine would translate the
+ * data to 0 to 15.
+ */
+void /* PRIVATE */
+png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
+{
+ png_debug(1, "in png_do_shift\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL &&
+#else
+ if (
+#endif
+ row_info->color_type != PNG_COLOR_TYPE_PALETTE)
+ {
+ int shift_start[4], shift_dec[4];
+ int channels = 0;
+
+ if (row_info->color_type & PNG_COLOR_MASK_COLOR)
+ {
+ shift_start[channels] = row_info->bit_depth - bit_depth->red;
+ shift_dec[channels] = bit_depth->red;
+ channels++;
+ shift_start[channels] = row_info->bit_depth - bit_depth->green;
+ shift_dec[channels] = bit_depth->green;
+ channels++;
+ shift_start[channels] = row_info->bit_depth - bit_depth->blue;
+ shift_dec[channels] = bit_depth->blue;
+ channels++;
+ }
+ else
+ {
+ shift_start[channels] = row_info->bit_depth - bit_depth->gray;
+ shift_dec[channels] = bit_depth->gray;
+ channels++;
+ }
+ if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+ {
+ shift_start[channels] = row_info->bit_depth - bit_depth->alpha;
+ shift_dec[channels] = bit_depth->alpha;
+ channels++;
+ }
+
+ /* with low row depths, could only be grayscale, so one channel */
+ if (row_info->bit_depth < 8)
+ {
+ png_bytep bp = row;
+ png_uint_32 i;
+ png_byte mask;
+ png_uint_32 row_bytes = row_info->rowbytes;
+
+ if (bit_depth->gray == 1 && row_info->bit_depth == 2)
+ mask = 0x55;
+ else if (row_info->bit_depth == 4 && bit_depth->gray == 3)
+ mask = 0x11;
+ else
+ mask = 0xff;
+
+ for (i = 0; i < row_bytes; i++, bp++)
+ {
+ png_uint_16 v;
+ int j;
+
+ v = *bp;
+ *bp = 0;
+ for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0])
+ {
+ if (j > 0)
+ *bp |= (png_byte)((v << j) & 0xff);
+ else
+ *bp |= (png_byte)((v >> (-j)) & mask);
+ }
+ }
+ }
+ else if (row_info->bit_depth == 8)
+ {
+ png_bytep bp = row;
+ png_uint_32 i;
+ png_uint_32 istop = channels * row_info->width;
+
+ for (i = 0; i < istop; i++, bp++)
+ {
+
+ png_uint_16 v;
+ int j;
+ int c = (int)(i%channels);
+
+ v = *bp;
+ *bp = 0;
+ for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
+ {
+ if (j > 0)
+ *bp |= (png_byte)((v << j) & 0xff);
+ else
+ *bp |= (png_byte)((v >> (-j)) & 0xff);
+ }
+ }
+ }
+ else
+ {
+ png_bytep bp;
+ png_uint_32 i;
+ png_uint_32 istop = channels * row_info->width;
+
+ for (bp = row, i = 0; i < istop; i++)
+ {
+ int c = (int)(i%channels);
+ png_uint_16 value, v;
+ int j;
+
+ v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1));
+ value = 0;
+ for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
+ {
+ if (j > 0)
+ value |= (png_uint_16)((v << j) & (png_uint_16)0xffff);
+ else
+ value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff);
+ }
+ *bp++ = (png_byte)(value >> 8);
+ *bp++ = (png_byte)(value & 0xff);
+ }
+ }
+ }
+}
+#endif
+
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_write_swap_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL)
+#endif
+ {
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ {
+ /* This converts from ARGB to RGBA */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ png_byte save = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = save;
+ }
+ }
+ /* This converts from AARRGGBB to RRGGBBAA */
+ else
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ png_byte save[2];
+ save[0] = *(sp++);
+ save[1] = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = save[0];
+ *(dp++) = save[1];
+ }
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ {
+ /* This converts from AG to GA */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ png_byte save = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = save;
+ }
+ }
+ /* This converts from AAGG to GGAA */
+ else
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ png_byte save[2];
+ save[0] = *(sp++);
+ save[1] = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = save[0];
+ *(dp++) = save[1];
+ }
+ }
+ }
+ }
+}
+#endif
+
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_write_invert_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL)
+#endif
+ {
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ {
+ /* This inverts the alpha channel in RGBA */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ /* does nothing
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ */
+ sp+=3; dp = sp;
+ *(dp++) = (png_byte)(255 - *(sp++));
+ }
+ }
+ /* This inverts the alpha channel in RRGGBBAA */
+ else
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ /* does nothing
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ */
+ sp+=6; dp = sp;
+ *(dp++) = (png_byte)(255 - *(sp++));
+ *(dp++) = (png_byte)(255 - *(sp++));
+ }
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ {
+ /* This inverts the alpha channel in GA */
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ *(dp++) = *(sp++);
+ *(dp++) = (png_byte)(255 - *(sp++));
+ }
+ }
+ /* This inverts the alpha channel in GGAA */
+ else
+ {
+ png_bytep sp, dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ for (i = 0, sp = dp = row; i < row_width; i++)
+ {
+ /* does nothing
+ *(dp++) = *(sp++);
+ *(dp++) = *(sp++);
+ */
+ sp+=2; dp = sp;
+ *(dp++) = (png_byte)(255 - *(sp++));
+ *(dp++) = (png_byte)(255 - *(sp++));
+ }
+ }
+ }
+ }
+}
+#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+/* undoes intrapixel differencing */
+void /* PRIVATE */
+png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_write_intrapixel\n");
+ if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ (row_info->color_type & PNG_COLOR_MASK_COLOR))
+ {
+ int bytes_per_pixel;
+ png_uint_32 row_width = row_info->width;
+ if (row_info->bit_depth == 8)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ bytes_per_pixel = 3;
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 4;
+ else
+ return;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ *(rp) = (png_byte)((*rp - *(rp+1))&0xff);
+ *(rp+2) = (png_byte)((*(rp+2) - *(rp+1))&0xff);
+ }
+ }
+ else if (row_info->bit_depth == 16)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+ bytes_per_pixel = 6;
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 8;
+ else
+ return;
+
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ png_uint_32 s0 = (*(rp ) << 8) | *(rp+1);
+ png_uint_32 s1 = (*(rp+2) << 8) | *(rp+3);
+ png_uint_32 s2 = (*(rp+4) << 8) | *(rp+5);
+ png_uint_32 red = (png_uint_32)((s0-s1) & 0xffffL);
+ png_uint_32 blue = (png_uint_32)((s2-s1) & 0xffffL);
+ *(rp ) = (png_byte)((red >> 8) & 0xff);
+ *(rp+1) = (png_byte)(red & 0xff);
+ *(rp+4) = (png_byte)((blue >> 8) & 0xff);
+ *(rp+5) = (png_byte)(blue & 0xff);
+ }
+ }
+ }
+}
+#endif /* PNG_MNG_FEATURES_SUPPORTED */
+#endif /* PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngwutil.c b/src/libpng/pngwutil.c
new file mode 100644
index 0000000..fef38ae
--- /dev/null
+++ b/src/libpng/pngwutil.c
@@ -0,0 +1,2792 @@
+
+/* pngwutil.c - utilities to write a PNG file
+ *
+ * Last changed in libpng 1.2.20 Septhember 3, 2007
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Place a 32-bit number into a buffer in PNG byte order. We work
+ * with unsigned numbers for convenience, although one supported
+ * ancillary chunk uses signed (two's complement) numbers.
+ */
+void PNGAPI
+png_save_uint_32(png_bytep buf, png_uint_32 i)
+{
+ buf[0] = (png_byte)((i >> 24) & 0xff);
+ buf[1] = (png_byte)((i >> 16) & 0xff);
+ buf[2] = (png_byte)((i >> 8) & 0xff);
+ buf[3] = (png_byte)(i & 0xff);
+}
+
+/* The png_save_int_32 function assumes integers are stored in two's
+ * complement format. If this isn't the case, then this routine needs to
+ * be modified to write data in two's complement format.
+ */
+void PNGAPI
+png_save_int_32(png_bytep buf, png_int_32 i)
+{
+ buf[0] = (png_byte)((i >> 24) & 0xff);
+ buf[1] = (png_byte)((i >> 16) & 0xff);
+ buf[2] = (png_byte)((i >> 8) & 0xff);
+ buf[3] = (png_byte)(i & 0xff);
+}
+
+/* Place a 16-bit number into a buffer in PNG byte order.
+ * The parameter is declared unsigned int, not png_uint_16,
+ * just to avoid potential problems on pre-ANSI C compilers.
+ */
+void PNGAPI
+png_save_uint_16(png_bytep buf, unsigned int i)
+{
+ buf[0] = (png_byte)((i >> 8) & 0xff);
+ buf[1] = (png_byte)(i & 0xff);
+}
+
+/* Write a PNG chunk all at once. The type is an array of ASCII characters
+ * representing the chunk name. The array must be at least 4 bytes in
+ * length, and does not need to be null terminated. To be safe, pass the
+ * pre-defined chunk names here, and if you need a new one, define it
+ * where the others are defined. The length is the length of the data.
+ * All the data must be present. If that is not possible, use the
+ * png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
+ * functions instead.
+ */
+void PNGAPI
+png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
+ png_bytep data, png_size_t length)
+{
+ if(png_ptr == NULL) return;
+ png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length);
+ png_write_chunk_data(png_ptr, data, length);
+ png_write_chunk_end(png_ptr);
+}
+
+/* Write the start of a PNG chunk. The type is the chunk type.
+ * The total_length is the sum of the lengths of all the data you will be
+ * passing in png_write_chunk_data().
+ */
+void PNGAPI
+png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name,
+ png_uint_32 length)
+{
+ png_byte buf[4];
+ png_debug2(0, "Writing %s chunk (%lu bytes)\n", chunk_name, length);
+ if(png_ptr == NULL) return;
+
+ /* write the length */
+ png_save_uint_32(buf, length);
+ png_write_data(png_ptr, buf, (png_size_t)4);
+
+ /* write the chunk name */
+ png_write_data(png_ptr, chunk_name, (png_size_t)4);
+ /* reset the crc and run it over the chunk name */
+ png_reset_crc(png_ptr);
+ png_calculate_crc(png_ptr, chunk_name, (png_size_t)4);
+}
+
+/* Write the data of a PNG chunk started with png_write_chunk_start().
+ * Note that multiple calls to this function are allowed, and that the
+ * sum of the lengths from these calls *must* add up to the total_length
+ * given to png_write_chunk_start().
+ */
+void PNGAPI
+png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ /* write the data, and run the CRC over it */
+ if(png_ptr == NULL) return;
+ if (data != NULL && length > 0)
+ {
+ png_calculate_crc(png_ptr, data, length);
+ png_write_data(png_ptr, data, length);
+ }
+}
+
+/* Finish a chunk started with png_write_chunk_start(). */
+void PNGAPI
+png_write_chunk_end(png_structp png_ptr)
+{
+ png_byte buf[4];
+
+ if(png_ptr == NULL) return;
+
+ /* write the crc */
+ png_save_uint_32(buf, png_ptr->crc);
+
+ png_write_data(png_ptr, buf, (png_size_t)4);
+}
+
+/* Simple function to write the signature. If we have already written
+ * the magic bytes of the signature, or more likely, the PNG stream is
+ * being embedded into another stream and doesn't need its own signature,
+ * we should call png_set_sig_bytes() to tell libpng how many of the
+ * bytes have already been written.
+ */
+void /* PRIVATE */
+png_write_sig(png_structp png_ptr)
+{
+ png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+ /* write the rest of the 8 byte signature */
+ png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes],
+ (png_size_t)8 - png_ptr->sig_bytes);
+ if(png_ptr->sig_bytes < 3)
+ png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
+}
+
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_iCCP_SUPPORTED)
+/*
+ * This pair of functions encapsulates the operation of (a) compressing a
+ * text string, and (b) issuing it later as a series of chunk data writes.
+ * The compression_state structure is shared context for these functions
+ * set up by the caller in order to make the whole mess thread-safe.
+ */
+
+typedef struct
+{
+ char *input; /* the uncompressed input data */
+ int input_len; /* its length */
+ int num_output_ptr; /* number of output pointers used */
+ int max_output_ptr; /* size of output_ptr */
+ png_charpp output_ptr; /* array of pointers to output */
+} compression_state;
+
+/* compress given text into storage in the png_ptr structure */
+static int /* PRIVATE */
+png_text_compress(png_structp png_ptr,
+ png_charp text, png_size_t text_len, int compression,
+ compression_state *comp)
+{
+ int ret;
+
+ comp->num_output_ptr = 0;
+ comp->max_output_ptr = 0;
+ comp->output_ptr = NULL;
+ comp->input = NULL;
+ comp->input_len = 0;
+
+ /* we may just want to pass the text right through */
+ if (compression == PNG_TEXT_COMPRESSION_NONE)
+ {
+ comp->input = text;
+ comp->input_len = text_len;
+ return((int)text_len);
+ }
+
+ if (compression >= PNG_TEXT_COMPRESSION_LAST)
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char msg[50];
+ png_snprintf(msg, 50, "Unknown compression type %d", compression);
+ png_warning(png_ptr, msg);
+#else
+ png_warning(png_ptr, "Unknown compression type");
+#endif
+ }
+
+ /* We can't write the chunk until we find out how much data we have,
+ * which means we need to run the compressor first and save the
+ * output. This shouldn't be a problem, as the vast majority of
+ * comments should be reasonable, but we will set up an array of
+ * malloc'd pointers to be sure.
+ *
+ * If we knew the application was well behaved, we could simplify this
+ * greatly by assuming we can always malloc an output buffer large
+ * enough to hold the compressed text ((1001 * text_len / 1000) + 12)
+ * and malloc this directly. The only time this would be a bad idea is
+ * if we can't malloc more than 64K and we have 64K of random input
+ * data, or if the input string is incredibly large (although this
+ * wouldn't cause a failure, just a slowdown due to swapping).
+ */
+
+ /* set up the compression buffers */
+ png_ptr->zstream.avail_in = (uInt)text_len;
+ png_ptr->zstream.next_in = (Bytef *)text;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf;
+
+ /* this is the same compression loop as in png_write_row() */
+ do
+ {
+ /* compress the data */
+ ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
+ if (ret != Z_OK)
+ {
+ /* error */
+ if (png_ptr->zstream.msg != NULL)
+ png_error(png_ptr, png_ptr->zstream.msg);
+ else
+ png_error(png_ptr, "zlib error");
+ }
+ /* check to see if we need more room */
+ if (!(png_ptr->zstream.avail_out))
+ {
+ /* make sure the output array has room */
+ if (comp->num_output_ptr >= comp->max_output_ptr)
+ {
+ int old_max;
+
+ old_max = comp->max_output_ptr;
+ comp->max_output_ptr = comp->num_output_ptr + 4;
+ if (comp->output_ptr != NULL)
+ {
+ png_charpp old_ptr;
+
+ old_ptr = comp->output_ptr;
+ comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+ (png_uint_32)(comp->max_output_ptr *
+ png_sizeof (png_charpp)));
+ png_memcpy(comp->output_ptr, old_ptr, old_max
+ * png_sizeof (png_charp));
+ png_free(png_ptr, old_ptr);
+ }
+ else
+ comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+ (png_uint_32)(comp->max_output_ptr *
+ png_sizeof (png_charp)));
+ }
+
+ /* save the data */
+ comp->output_ptr[comp->num_output_ptr] = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)png_ptr->zbuf_size);
+ png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf,
+ png_ptr->zbuf_size);
+ comp->num_output_ptr++;
+
+ /* and reset the buffer */
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ }
+ /* continue until we don't have any more to compress */
+ } while (png_ptr->zstream.avail_in);
+
+ /* finish the compression */
+ do
+ {
+ /* tell zlib we are finished */
+ ret = deflate(&png_ptr->zstream, Z_FINISH);
+
+ if (ret == Z_OK)
+ {
+ /* check to see if we need more room */
+ if (!(png_ptr->zstream.avail_out))
+ {
+ /* check to make sure our output array has room */
+ if (comp->num_output_ptr >= comp->max_output_ptr)
+ {
+ int old_max;
+
+ old_max = comp->max_output_ptr;
+ comp->max_output_ptr = comp->num_output_ptr + 4;
+ if (comp->output_ptr != NULL)
+ {
+ png_charpp old_ptr;
+
+ old_ptr = comp->output_ptr;
+ /* This could be optimized to realloc() */
+ comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+ (png_uint_32)(comp->max_output_ptr *
+ png_sizeof (png_charpp)));
+ png_memcpy(comp->output_ptr, old_ptr,
+ old_max * png_sizeof (png_charp));
+ png_free(png_ptr, old_ptr);
+ }
+ else
+ comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+ (png_uint_32)(comp->max_output_ptr *
+ png_sizeof (png_charp)));
+ }
+
+ /* save off the data */
+ comp->output_ptr[comp->num_output_ptr] =
+ (png_charp)png_malloc(png_ptr, (png_uint_32)png_ptr->zbuf_size);
+ png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf,
+ png_ptr->zbuf_size);
+ comp->num_output_ptr++;
+
+ /* and reset the buffer pointers */
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ }
+ }
+ else if (ret != Z_STREAM_END)
+ {
+ /* we got an error */
+ if (png_ptr->zstream.msg != NULL)
+ png_error(png_ptr, png_ptr->zstream.msg);
+ else
+ png_error(png_ptr, "zlib error");
+ }
+ } while (ret != Z_STREAM_END);
+
+ /* text length is number of buffers plus last buffer */
+ text_len = png_ptr->zbuf_size * comp->num_output_ptr;
+ if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
+ text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out;
+
+ return((int)text_len);
+}
+
+/* ship the compressed text out via chunk writes */
+static void /* PRIVATE */
+png_write_compressed_data_out(png_structp png_ptr, compression_state *comp)
+{
+ int i;
+
+ /* handle the no-compression case */
+ if (comp->input)
+ {
+ png_write_chunk_data(png_ptr, (png_bytep)comp->input,
+ (png_size_t)comp->input_len);
+ return;
+ }
+
+ /* write saved output buffers, if any */
+ for (i = 0; i < comp->num_output_ptr; i++)
+ {
+ png_write_chunk_data(png_ptr,(png_bytep)comp->output_ptr[i],
+ png_ptr->zbuf_size);
+ png_free(png_ptr, comp->output_ptr[i]);
+ comp->output_ptr[i]=NULL;
+ }
+ if (comp->max_output_ptr != 0)
+ png_free(png_ptr, comp->output_ptr);
+ comp->output_ptr=NULL;
+ /* write anything left in zbuf */
+ if (png_ptr->zstream.avail_out < (png_uint_32)png_ptr->zbuf_size)
+ png_write_chunk_data(png_ptr, png_ptr->zbuf,
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+
+ /* reset zlib for another zTXt/iTXt or image data */
+ deflateReset(&png_ptr->zstream);
+ png_ptr->zstream.data_type = Z_BINARY;
+}
+#endif
+
+/* Write the IHDR chunk, and update the png_struct with the necessary
+ * information. Note that the rest of this code depends upon this
+ * information being correct.
+ */
+void /* PRIVATE */
+png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
+ int bit_depth, int color_type, int compression_type, int filter_type,
+ int interlace_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_IHDR;
+#endif
+ png_byte buf[13]; /* buffer to store the IHDR info */
+
+ png_debug(1, "in png_write_IHDR\n");
+ /* Check that we have valid input data from the application info */
+ switch (color_type)
+ {
+ case PNG_COLOR_TYPE_GRAY:
+ switch (bit_depth)
+ {
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ case 16: png_ptr->channels = 1; break;
+ default: png_error(png_ptr,"Invalid bit depth for grayscale image");
+ }
+ break;
+ case PNG_COLOR_TYPE_RGB:
+ if (bit_depth != 8 && bit_depth != 16)
+ png_error(png_ptr, "Invalid bit depth for RGB image");
+ png_ptr->channels = 3;
+ break;
+ case PNG_COLOR_TYPE_PALETTE:
+ switch (bit_depth)
+ {
+ case 1:
+ case 2:
+ case 4:
+ case 8: png_ptr->channels = 1; break;
+ default: png_error(png_ptr, "Invalid bit depth for paletted image");
+ }
+ break;
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ if (bit_depth != 8 && bit_depth != 16)
+ png_error(png_ptr, "Invalid bit depth for grayscale+alpha image");
+ png_ptr->channels = 2;
+ break;
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ if (bit_depth != 8 && bit_depth != 16)
+ png_error(png_ptr, "Invalid bit depth for RGBA image");
+ png_ptr->channels = 4;
+ break;
+ default:
+ png_error(png_ptr, "Invalid image color type specified");
+ }
+
+ if (compression_type != PNG_COMPRESSION_TYPE_BASE)
+ {
+ png_warning(png_ptr, "Invalid compression type specified");
+ compression_type = PNG_COMPRESSION_TYPE_BASE;
+ }
+
+ /* Write filter_method 64 (intrapixel differencing) only if
+ * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+ * 2. Libpng did not write a PNG signature (this filter_method is only
+ * used in PNG datastreams that are embedded in MNG datastreams) and
+ * 3. The application called png_permit_mng_features with a mask that
+ * included PNG_FLAG_MNG_FILTER_64 and
+ * 4. The filter_method is 64 and
+ * 5. The color_type is RGB or RGBA
+ */
+ if (
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+ ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
+ (color_type == PNG_COLOR_TYPE_RGB ||
+ color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
+ (filter_type == PNG_INTRAPIXEL_DIFFERENCING)) &&
+#endif
+ filter_type != PNG_FILTER_TYPE_BASE)
+ {
+ png_warning(png_ptr, "Invalid filter type specified");
+ filter_type = PNG_FILTER_TYPE_BASE;
+ }
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+ if (interlace_type != PNG_INTERLACE_NONE &&
+ interlace_type != PNG_INTERLACE_ADAM7)
+ {
+ png_warning(png_ptr, "Invalid interlace type specified");
+ interlace_type = PNG_INTERLACE_ADAM7;
+ }
+#else
+ interlace_type=PNG_INTERLACE_NONE;
+#endif
+
+ /* save off the relevent information */
+ png_ptr->bit_depth = (png_byte)bit_depth;
+ png_ptr->color_type = (png_byte)color_type;
+ png_ptr->interlaced = (png_byte)interlace_type;
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ png_ptr->filter_type = (png_byte)filter_type;
+#endif
+ png_ptr->compression_type = (png_byte)compression_type;
+ png_ptr->width = width;
+ png_ptr->height = height;
+
+ png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
+ png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width);
+ /* set the usr info, so any transformations can modify it */
+ png_ptr->usr_width = png_ptr->width;
+ png_ptr->usr_bit_depth = png_ptr->bit_depth;
+ png_ptr->usr_channels = png_ptr->channels;
+
+ /* pack the header information into the buffer */
+ png_save_uint_32(buf, width);
+ png_save_uint_32(buf + 4, height);
+ buf[8] = (png_byte)bit_depth;
+ buf[9] = (png_byte)color_type;
+ buf[10] = (png_byte)compression_type;
+ buf[11] = (png_byte)filter_type;
+ buf[12] = (png_byte)interlace_type;
+
+ /* write the chunk */
+ png_write_chunk(png_ptr, png_IHDR, buf, (png_size_t)13);
+
+ /* initialize zlib with PNG info */
+ png_ptr->zstream.zalloc = png_zalloc;
+ png_ptr->zstream.zfree = png_zfree;
+ png_ptr->zstream.opaque = (voidpf)png_ptr;
+ if (!(png_ptr->do_filter))
+ {
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
+ png_ptr->bit_depth < 8)
+ png_ptr->do_filter = PNG_FILTER_NONE;
+ else
+ png_ptr->do_filter = PNG_ALL_FILTERS;
+ }
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY))
+ {
+ if (png_ptr->do_filter != PNG_FILTER_NONE)
+ png_ptr->zlib_strategy = Z_FILTERED;
+ else
+ png_ptr->zlib_strategy = Z_DEFAULT_STRATEGY;
+ }
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_LEVEL))
+ png_ptr->zlib_level = Z_DEFAULT_COMPRESSION;
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL))
+ png_ptr->zlib_mem_level = 8;
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS))
+ png_ptr->zlib_window_bits = 15;
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
+ png_ptr->zlib_method = 8;
+ if (deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
+ png_ptr->zlib_method, png_ptr->zlib_window_bits,
+ png_ptr->zlib_mem_level, png_ptr->zlib_strategy) != Z_OK)
+ png_error(png_ptr, "zlib failed to initialize compressor");
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ /* libpng is not interested in zstream.data_type */
+ /* set it to a predefined value, to avoid its evaluation inside zlib */
+ png_ptr->zstream.data_type = Z_BINARY;
+
+ png_ptr->mode = PNG_HAVE_IHDR;
+}
+
+/* write the palette. We are careful not to trust png_color to be in the
+ * correct order for PNG, so people can redefine it to any convenient
+ * structure.
+ */
+void /* PRIVATE */
+png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_PLTE;
+#endif
+ png_uint_32 i;
+ png_colorp pal_ptr;
+ png_byte buf[3];
+
+ png_debug(1, "in png_write_PLTE\n");
+ if ((
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ !(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) &&
+#endif
+ num_pal == 0) || num_pal > 256)
+ {
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ png_error(png_ptr, "Invalid number of colors in palette");
+ }
+ else
+ {
+ png_warning(png_ptr, "Invalid number of colors in palette");
+ return;
+ }
+ }
+
+ if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
+ {
+ png_warning(png_ptr,
+ "Ignoring request to write a PLTE chunk in grayscale PNG");
+ return;
+ }
+
+ png_ptr->num_palette = (png_uint_16)num_pal;
+ png_debug1(3, "num_palette = %d\n", png_ptr->num_palette);
+
+ png_write_chunk_start(png_ptr, png_PLTE, num_pal * 3);
+#ifndef PNG_NO_POINTER_INDEXING
+ for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
+ {
+ buf[0] = pal_ptr->red;
+ buf[1] = pal_ptr->green;
+ buf[2] = pal_ptr->blue;
+ png_write_chunk_data(png_ptr, buf, (png_size_t)3);
+ }
+#else
+ /* This is a little slower but some buggy compilers need to do this instead */
+ pal_ptr=palette;
+ for (i = 0; i < num_pal; i++)
+ {
+ buf[0] = pal_ptr[i].red;
+ buf[1] = pal_ptr[i].green;
+ buf[2] = pal_ptr[i].blue;
+ png_write_chunk_data(png_ptr, buf, (png_size_t)3);
+ }
+#endif
+ png_write_chunk_end(png_ptr);
+ png_ptr->mode |= PNG_HAVE_PLTE;
+}
+
+/* write an IDAT chunk */
+void /* PRIVATE */
+png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_IDAT;
+#endif
+ png_debug(1, "in png_write_IDAT\n");
+
+ /* Optimize the CMF field in the zlib stream. */
+ /* This hack of the zlib stream is compliant to the stream specification. */
+ if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
+ png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
+ {
+ unsigned int z_cmf = data[0]; /* zlib compression method and flags */
+ if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
+ {
+ /* Avoid memory underflows and multiplication overflows. */
+ /* The conditions below are practically always satisfied;
+ however, they still must be checked. */
+ if (length >= 2 &&
+ png_ptr->height < 16384 && png_ptr->width < 16384)
+ {
+ png_uint_32 uncompressed_idat_size = png_ptr->height *
+ ((png_ptr->width *
+ png_ptr->channels * png_ptr->bit_depth + 15) >> 3);
+ unsigned int z_cinfo = z_cmf >> 4;
+ unsigned int half_z_window_size = 1 << (z_cinfo + 7);
+ while (uncompressed_idat_size <= half_z_window_size &&
+ half_z_window_size >= 256)
+ {
+ z_cinfo--;
+ half_z_window_size >>= 1;
+ }
+ z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4);
+ if (data[0] != (png_byte)z_cmf)
+ {
+ data[0] = (png_byte)z_cmf;
+ data[1] &= 0xe0;
+ data[1] += (png_byte)(0x1f - ((z_cmf << 8) + data[1]) % 0x1f);
+ }
+ }
+ }
+ else
+ png_error(png_ptr,
+ "Invalid zlib compression method or flags in IDAT");
+ }
+
+ png_write_chunk(png_ptr, png_IDAT, data, length);
+ png_ptr->mode |= PNG_HAVE_IDAT;
+}
+
+/* write an IEND chunk */
+void /* PRIVATE */
+png_write_IEND(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_IEND;
+#endif
+ png_debug(1, "in png_write_IEND\n");
+ png_write_chunk(png_ptr, png_IEND, png_bytep_NULL,
+ (png_size_t)0);
+ png_ptr->mode |= PNG_HAVE_IEND;
+}
+
+#if defined(PNG_WRITE_gAMA_SUPPORTED)
+/* write a gAMA chunk */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_gAMA(png_structp png_ptr, double file_gamma)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_gAMA;
+#endif
+ png_uint_32 igamma;
+ png_byte buf[4];
+
+ png_debug(1, "in png_write_gAMA\n");
+ /* file_gamma is saved in 1/100,000ths */
+ igamma = (png_uint_32)(file_gamma * 100000.0 + 0.5);
+ png_save_uint_32(buf, igamma);
+ png_write_chunk(png_ptr, png_gAMA, buf, (png_size_t)4);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_gAMA_fixed(png_structp png_ptr, png_fixed_point file_gamma)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_gAMA;
+#endif
+ png_byte buf[4];
+
+ png_debug(1, "in png_write_gAMA\n");
+ /* file_gamma is saved in 1/100,000ths */
+ png_save_uint_32(buf, (png_uint_32)file_gamma);
+ png_write_chunk(png_ptr, png_gAMA, buf, (png_size_t)4);
+}
+#endif
+#endif
+
+#if defined(PNG_WRITE_sRGB_SUPPORTED)
+/* write a sRGB chunk */
+void /* PRIVATE */
+png_write_sRGB(png_structp png_ptr, int srgb_intent)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_sRGB;
+#endif
+ png_byte buf[1];
+
+ png_debug(1, "in png_write_sRGB\n");
+ if(srgb_intent >= PNG_sRGB_INTENT_LAST)
+ png_warning(png_ptr,
+ "Invalid sRGB rendering intent specified");
+ buf[0]=(png_byte)srgb_intent;
+ png_write_chunk(png_ptr, png_sRGB, buf, (png_size_t)1);
+}
+#endif
+
+#if defined(PNG_WRITE_iCCP_SUPPORTED)
+/* write an iCCP chunk */
+void /* PRIVATE */
+png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type,
+ png_charp profile, int profile_len)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_iCCP;
+#endif
+ png_size_t name_len;
+ png_charp new_name;
+ compression_state comp;
+ int embedded_profile_len = 0;
+
+ png_debug(1, "in png_write_iCCP\n");
+
+ comp.num_output_ptr = 0;
+ comp.max_output_ptr = 0;
+ comp.output_ptr = NULL;
+ comp.input = NULL;
+ comp.input_len = 0;
+
+ if (name == NULL || (name_len = png_check_keyword(png_ptr, name,
+ &new_name)) == 0)
+ {
+ png_warning(png_ptr, "Empty keyword in iCCP chunk");
+ return;
+ }
+
+ if (compression_type != PNG_COMPRESSION_TYPE_BASE)
+ png_warning(png_ptr, "Unknown compression type in iCCP chunk");
+
+ if (profile == NULL)
+ profile_len = 0;
+
+ if (profile_len > 3)
+ embedded_profile_len =
+ ((*( (png_bytep)profile ))<<24) |
+ ((*( (png_bytep)profile+1))<<16) |
+ ((*( (png_bytep)profile+2))<< 8) |
+ ((*( (png_bytep)profile+3)) );
+
+ if (profile_len < embedded_profile_len)
+ {
+ png_warning(png_ptr,
+ "Embedded profile length too large in iCCP chunk");
+ return;
+ }
+
+ if (profile_len > embedded_profile_len)
+ {
+ png_warning(png_ptr,
+ "Truncating profile to actual length in iCCP chunk");
+ profile_len = embedded_profile_len;
+ }
+
+ if (profile_len)
+ profile_len = png_text_compress(png_ptr, profile, (png_size_t)profile_len,
+ PNG_COMPRESSION_TYPE_BASE, &comp);
+
+ /* make sure we include the NULL after the name and the compression type */
+ png_write_chunk_start(png_ptr, png_iCCP,
+ (png_uint_32)name_len+profile_len+2);
+ new_name[name_len+1]=0x00;
+ png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 2);
+
+ if (profile_len)
+ png_write_compressed_data_out(png_ptr, &comp);
+
+ png_write_chunk_end(png_ptr);
+ png_free(png_ptr, new_name);
+}
+#endif
+
+#if defined(PNG_WRITE_sPLT_SUPPORTED)
+/* write a sPLT chunk */
+void /* PRIVATE */
+png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_sPLT;
+#endif
+ png_size_t name_len;
+ png_charp new_name;
+ png_byte entrybuf[10];
+ int entry_size = (spalette->depth == 8 ? 6 : 10);
+ int palette_size = entry_size * spalette->nentries;
+ png_sPLT_entryp ep;
+#ifdef PNG_NO_POINTER_INDEXING
+ int i;
+#endif
+
+ png_debug(1, "in png_write_sPLT\n");
+ if (spalette->name == NULL || (name_len = png_check_keyword(png_ptr,
+ spalette->name, &new_name))==0)
+ {
+ png_warning(png_ptr, "Empty keyword in sPLT chunk");
+ return;
+ }
+
+ /* make sure we include the NULL after the name */
+ png_write_chunk_start(png_ptr, png_sPLT,
+ (png_uint_32)(name_len + 2 + palette_size));
+ png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 1);
+ png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, 1);
+
+ /* loop through each palette entry, writing appropriately */
+#ifndef PNG_NO_POINTER_INDEXING
+ for (ep = spalette->entries; ep<spalette->entries+spalette->nentries; ep++)
+ {
+ if (spalette->depth == 8)
+ {
+ entrybuf[0] = (png_byte)ep->red;
+ entrybuf[1] = (png_byte)ep->green;
+ entrybuf[2] = (png_byte)ep->blue;
+ entrybuf[3] = (png_byte)ep->alpha;
+ png_save_uint_16(entrybuf + 4, ep->frequency);
+ }
+ else
+ {
+ png_save_uint_16(entrybuf + 0, ep->red);
+ png_save_uint_16(entrybuf + 2, ep->green);
+ png_save_uint_16(entrybuf + 4, ep->blue);
+ png_save_uint_16(entrybuf + 6, ep->alpha);
+ png_save_uint_16(entrybuf + 8, ep->frequency);
+ }
+ png_write_chunk_data(png_ptr, entrybuf, (png_size_t)entry_size);
+ }
+#else
+ ep=spalette->entries;
+ for (i=0; i>spalette->nentries; i++)
+ {
+ if (spalette->depth == 8)
+ {
+ entrybuf[0] = (png_byte)ep[i].red;
+ entrybuf[1] = (png_byte)ep[i].green;
+ entrybuf[2] = (png_byte)ep[i].blue;
+ entrybuf[3] = (png_byte)ep[i].alpha;
+ png_save_uint_16(entrybuf + 4, ep[i].frequency);
+ }
+ else
+ {
+ png_save_uint_16(entrybuf + 0, ep[i].red);
+ png_save_uint_16(entrybuf + 2, ep[i].green);
+ png_save_uint_16(entrybuf + 4, ep[i].blue);
+ png_save_uint_16(entrybuf + 6, ep[i].alpha);
+ png_save_uint_16(entrybuf + 8, ep[i].frequency);
+ }
+ png_write_chunk_data(png_ptr, entrybuf, entry_size);
+ }
+#endif
+
+ png_write_chunk_end(png_ptr);
+ png_free(png_ptr, new_name);
+}
+#endif
+
+#if defined(PNG_WRITE_sBIT_SUPPORTED)
+/* write the sBIT chunk */
+void /* PRIVATE */
+png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_sBIT;
+#endif
+ png_byte buf[4];
+ png_size_t size;
+
+ png_debug(1, "in png_write_sBIT\n");
+ /* make sure we don't depend upon the order of PNG_COLOR_8 */
+ if (color_type & PNG_COLOR_MASK_COLOR)
+ {
+ png_byte maxbits;
+
+ maxbits = (png_byte)(color_type==PNG_COLOR_TYPE_PALETTE ? 8 :
+ png_ptr->usr_bit_depth);
+ if (sbit->red == 0 || sbit->red > maxbits ||
+ sbit->green == 0 || sbit->green > maxbits ||
+ sbit->blue == 0 || sbit->blue > maxbits)
+ {
+ png_warning(png_ptr, "Invalid sBIT depth specified");
+ return;
+ }
+ buf[0] = sbit->red;
+ buf[1] = sbit->green;
+ buf[2] = sbit->blue;
+ size = 3;
+ }
+ else
+ {
+ if (sbit->gray == 0 || sbit->gray > png_ptr->usr_bit_depth)
+ {
+ png_warning(png_ptr, "Invalid sBIT depth specified");
+ return;
+ }
+ buf[0] = sbit->gray;
+ size = 1;
+ }
+
+ if (color_type & PNG_COLOR_MASK_ALPHA)
+ {
+ if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth)
+ {
+ png_warning(png_ptr, "Invalid sBIT depth specified");
+ return;
+ }
+ buf[size++] = sbit->alpha;
+ }
+
+ png_write_chunk(png_ptr, png_sBIT, buf, size);
+}
+#endif
+
+#if defined(PNG_WRITE_cHRM_SUPPORTED)
+/* write the cHRM chunk */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
+ double red_x, double red_y, double green_x, double green_y,
+ double blue_x, double blue_y)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_cHRM;
+#endif
+ png_byte buf[32];
+ png_uint_32 itemp;
+
+ png_debug(1, "in png_write_cHRM\n");
+ /* each value is saved in 1/100,000ths */
+ if (white_x < 0 || white_x > 0.8 || white_y < 0 || white_y > 0.8 ||
+ white_x + white_y > 1.0)
+ {
+ png_warning(png_ptr, "Invalid cHRM white point specified");
+#if !defined(PNG_NO_CONSOLE_IO)
+ fprintf(stderr,"white_x=%f, white_y=%f\n",white_x, white_y);
+#endif
+ return;
+ }
+ itemp = (png_uint_32)(white_x * 100000.0 + 0.5);
+ png_save_uint_32(buf, itemp);
+ itemp = (png_uint_32)(white_y * 100000.0 + 0.5);
+ png_save_uint_32(buf + 4, itemp);
+
+ if (red_x < 0 || red_y < 0 || red_x + red_y > 1.0)
+ {
+ png_warning(png_ptr, "Invalid cHRM red point specified");
+ return;
+ }
+ itemp = (png_uint_32)(red_x * 100000.0 + 0.5);
+ png_save_uint_32(buf + 8, itemp);
+ itemp = (png_uint_32)(red_y * 100000.0 + 0.5);
+ png_save_uint_32(buf + 12, itemp);
+
+ if (green_x < 0 || green_y < 0 || green_x + green_y > 1.0)
+ {
+ png_warning(png_ptr, "Invalid cHRM green point specified");
+ return;
+ }
+ itemp = (png_uint_32)(green_x * 100000.0 + 0.5);
+ png_save_uint_32(buf + 16, itemp);
+ itemp = (png_uint_32)(green_y * 100000.0 + 0.5);
+ png_save_uint_32(buf + 20, itemp);
+
+ if (blue_x < 0 || blue_y < 0 || blue_x + blue_y > 1.0)
+ {
+ png_warning(png_ptr, "Invalid cHRM blue point specified");
+ return;
+ }
+ itemp = (png_uint_32)(blue_x * 100000.0 + 0.5);
+ png_save_uint_32(buf + 24, itemp);
+ itemp = (png_uint_32)(blue_y * 100000.0 + 0.5);
+ png_save_uint_32(buf + 28, itemp);
+
+ png_write_chunk(png_ptr, png_cHRM, buf, (png_size_t)32);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x,
+ png_fixed_point white_y, png_fixed_point red_x, png_fixed_point red_y,
+ png_fixed_point green_x, png_fixed_point green_y, png_fixed_point blue_x,
+ png_fixed_point blue_y)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_cHRM;
+#endif
+ png_byte buf[32];
+
+ png_debug(1, "in png_write_cHRM\n");
+ /* each value is saved in 1/100,000ths */
+ if (white_x > 80000L || white_y > 80000L || white_x + white_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid fixed cHRM white point specified");
+#if !defined(PNG_NO_CONSOLE_IO)
+ fprintf(stderr,"white_x=%ld, white_y=%ld\n",white_x, white_y);
+#endif
+ return;
+ }
+ png_save_uint_32(buf, (png_uint_32)white_x);
+ png_save_uint_32(buf + 4, (png_uint_32)white_y);
+
+ if (red_x + red_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid cHRM fixed red point specified");
+ return;
+ }
+ png_save_uint_32(buf + 8, (png_uint_32)red_x);
+ png_save_uint_32(buf + 12, (png_uint_32)red_y);
+
+ if (green_x + green_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid fixed cHRM green point specified");
+ return;
+ }
+ png_save_uint_32(buf + 16, (png_uint_32)green_x);
+ png_save_uint_32(buf + 20, (png_uint_32)green_y);
+
+ if (blue_x + blue_y > 100000L)
+ {
+ png_warning(png_ptr, "Invalid fixed cHRM blue point specified");
+ return;
+ }
+ png_save_uint_32(buf + 24, (png_uint_32)blue_x);
+ png_save_uint_32(buf + 28, (png_uint_32)blue_y);
+
+ png_write_chunk(png_ptr, png_cHRM, buf, (png_size_t)32);
+}
+#endif
+#endif
+
+#if defined(PNG_WRITE_tRNS_SUPPORTED)
+/* write the tRNS chunk */
+void /* PRIVATE */
+png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
+ int num_trans, int color_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_tRNS;
+#endif
+ png_byte buf[6];
+
+ png_debug(1, "in png_write_tRNS\n");
+ if (color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette)
+ {
+ png_warning(png_ptr,"Invalid number of transparent colors specified");
+ return;
+ }
+ /* write the chunk out as it is */
+ png_write_chunk(png_ptr, png_tRNS, trans, (png_size_t)num_trans);
+ }
+ else if (color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ /* one 16 bit value */
+ if(tran->gray >= (1 << png_ptr->bit_depth))
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to write tRNS chunk out-of-range for bit_depth");
+ return;
+ }
+ png_save_uint_16(buf, tran->gray);
+ png_write_chunk(png_ptr, png_tRNS, buf, (png_size_t)2);
+ }
+ else if (color_type == PNG_COLOR_TYPE_RGB)
+ {
+ /* three 16 bit values */
+ png_save_uint_16(buf, tran->red);
+ png_save_uint_16(buf + 2, tran->green);
+ png_save_uint_16(buf + 4, tran->blue);
+ if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8");
+ return;
+ }
+ png_write_chunk(png_ptr, png_tRNS, buf, (png_size_t)6);
+ }
+ else
+ {
+ png_warning(png_ptr, "Can't write tRNS with an alpha channel");
+ }
+}
+#endif
+
+#if defined(PNG_WRITE_bKGD_SUPPORTED)
+/* write the background chunk */
+void /* PRIVATE */
+png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_bKGD;
+#endif
+ png_byte buf[6];
+
+ png_debug(1, "in png_write_bKGD\n");
+ if (color_type == PNG_COLOR_TYPE_PALETTE)
+ {
+ if (
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+ (png_ptr->num_palette ||
+ (!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) &&
+#endif
+ back->index > png_ptr->num_palette)
+ {
+ png_warning(png_ptr, "Invalid background palette index");
+ return;
+ }
+ buf[0] = back->index;
+ png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)1);
+ }
+ else if (color_type & PNG_COLOR_MASK_COLOR)
+ {
+ png_save_uint_16(buf, back->red);
+ png_save_uint_16(buf + 2, back->green);
+ png_save_uint_16(buf + 4, back->blue);
+ if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to write 16-bit bKGD chunk when bit_depth is 8");
+ return;
+ }
+ png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)6);
+ }
+ else
+ {
+ if(back->gray >= (1 << png_ptr->bit_depth))
+ {
+ png_warning(png_ptr,
+ "Ignoring attempt to write bKGD chunk out-of-range for bit_depth");
+ return;
+ }
+ png_save_uint_16(buf, back->gray);
+ png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)2);
+ }
+}
+#endif
+
+#if defined(PNG_WRITE_hIST_SUPPORTED)
+/* write the histogram */
+void /* PRIVATE */
+png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_hIST;
+#endif
+ int i;
+ png_byte buf[3];
+
+ png_debug(1, "in png_write_hIST\n");
+ if (num_hist > (int)png_ptr->num_palette)
+ {
+ png_debug2(3, "num_hist = %d, num_palette = %d\n", num_hist,
+ png_ptr->num_palette);
+ png_warning(png_ptr, "Invalid number of histogram entries specified");
+ return;
+ }
+
+ png_write_chunk_start(png_ptr, png_hIST, (png_uint_32)(num_hist * 2));
+ for (i = 0; i < num_hist; i++)
+ {
+ png_save_uint_16(buf, hist[i]);
+ png_write_chunk_data(png_ptr, buf, (png_size_t)2);
+ }
+ png_write_chunk_end(png_ptr);
+}
+#endif
+
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
+ defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
+ * and if invalid, correct the keyword rather than discarding the entire
+ * chunk. The PNG 1.0 specification requires keywords 1-79 characters in
+ * length, forbids leading or trailing whitespace, multiple internal spaces,
+ * and the non-break space (0x80) from ISO 8859-1. Returns keyword length.
+ *
+ * The new_key is allocated to hold the corrected keyword and must be freed
+ * by the calling routine. This avoids problems with trying to write to
+ * static keywords without having to have duplicate copies of the strings.
+ */
+png_size_t /* PRIVATE */
+png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
+{
+ png_size_t key_len;
+ png_charp kp, dp;
+ int kflag;
+ int kwarn=0;
+
+ png_debug(1, "in png_check_keyword\n");
+ *new_key = NULL;
+
+ if (key == NULL || (key_len = png_strlen(key)) == 0)
+ {
+ png_warning(png_ptr, "zero length keyword");
+ return ((png_size_t)0);
+ }
+
+ png_debug1(2, "Keyword to be checked is '%s'\n", key);
+
+ *new_key = (png_charp)png_malloc_warn(png_ptr, (png_uint_32)(key_len + 2));
+ if (*new_key == NULL)
+ {
+ png_warning(png_ptr, "Out of memory while procesing keyword");
+ return ((png_size_t)0);
+ }
+
+ /* Replace non-printing characters with a blank and print a warning */
+ for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
+ {
+ if ((png_byte)*kp < 0x20 ||
+ ((png_byte)*kp > 0x7E && (png_byte)*kp < 0xA1))
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char msg[40];
+
+ png_snprintf(msg, 40,
+ "invalid keyword character 0x%02X", (png_byte)*kp);
+ png_warning(png_ptr, msg);
+#else
+ png_warning(png_ptr, "invalid character in keyword");
+#endif
+ *dp = ' ';
+ }
+ else
+ {
+ *dp = *kp;
+ }
+ }
+ *dp = '\0';
+
+ /* Remove any trailing white space. */
+ kp = *new_key + key_len - 1;
+ if (*kp == ' ')
+ {
+ png_warning(png_ptr, "trailing spaces removed from keyword");
+
+ while (*kp == ' ')
+ {
+ *(kp--) = '\0';
+ key_len--;
+ }
+ }
+
+ /* Remove any leading white space. */
+ kp = *new_key;
+ if (*kp == ' ')
+ {
+ png_warning(png_ptr, "leading spaces removed from keyword");
+
+ while (*kp == ' ')
+ {
+ kp++;
+ key_len--;
+ }
+ }
+
+ png_debug1(2, "Checking for multiple internal spaces in '%s'\n", kp);
+
+ /* Remove multiple internal spaces. */
+ for (kflag = 0, dp = *new_key; *kp != '\0'; kp++)
+ {
+ if (*kp == ' ' && kflag == 0)
+ {
+ *(dp++) = *kp;
+ kflag = 1;
+ }
+ else if (*kp == ' ')
+ {
+ key_len--;
+ kwarn=1;
+ }
+ else
+ {
+ *(dp++) = *kp;
+ kflag = 0;
+ }
+ }
+ *dp = '\0';
+ if(kwarn)
+ png_warning(png_ptr, "extra interior spaces removed from keyword");
+
+ if (key_len == 0)
+ {
+ png_free(png_ptr, *new_key);
+ *new_key=NULL;
+ png_warning(png_ptr, "Zero length keyword");
+ }
+
+ if (key_len > 79)
+ {
+ png_warning(png_ptr, "keyword length must be 1 - 79 characters");
+ new_key[79] = '\0';
+ key_len = 79;
+ }
+
+ return (key_len);
+}
+#endif
+
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+/* write a tEXt chunk */
+void /* PRIVATE */
+png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
+ png_size_t text_len)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_tEXt;
+#endif
+ png_size_t key_len;
+ png_charp new_key;
+
+ png_debug(1, "in png_write_tEXt\n");
+ if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
+ {
+ png_warning(png_ptr, "Empty keyword in tEXt chunk");
+ return;
+ }
+
+ if (text == NULL || *text == '\0')
+ text_len = 0;
+ else
+ text_len = png_strlen(text);
+
+ /* make sure we include the 0 after the key */
+ png_write_chunk_start(png_ptr, png_tEXt, (png_uint_32)key_len+text_len+1);
+ /*
+ * We leave it to the application to meet PNG-1.0 requirements on the
+ * contents of the text. PNG-1.0 through PNG-1.2 discourage the use of
+ * any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them.
+ * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG.
+ */
+ png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
+ if (text_len)
+ png_write_chunk_data(png_ptr, (png_bytep)text, text_len);
+
+ png_write_chunk_end(png_ptr);
+ png_free(png_ptr, new_key);
+}
+#endif
+
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+/* write a compressed text chunk */
+void /* PRIVATE */
+png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
+ png_size_t text_len, int compression)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_zTXt;
+#endif
+ png_size_t key_len;
+ char buf[1];
+ png_charp new_key;
+ compression_state comp;
+
+ png_debug(1, "in png_write_zTXt\n");
+
+ comp.num_output_ptr = 0;
+ comp.max_output_ptr = 0;
+ comp.output_ptr = NULL;
+ comp.input = NULL;
+ comp.input_len = 0;
+
+ if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
+ {
+ png_warning(png_ptr, "Empty keyword in zTXt chunk");
+ return;
+ }
+
+ if (text == NULL || *text == '\0' || compression==PNG_TEXT_COMPRESSION_NONE)
+ {
+ png_write_tEXt(png_ptr, new_key, text, (png_size_t)0);
+ png_free(png_ptr, new_key);
+ return;
+ }
+
+ text_len = png_strlen(text);
+
+ /* compute the compressed data; do it now for the length */
+ text_len = png_text_compress(png_ptr, text, text_len, compression,
+ &comp);
+
+ /* write start of chunk */
+ png_write_chunk_start(png_ptr, png_zTXt, (png_uint_32)
+ (key_len+text_len+2));
+ /* write key */
+ png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
+ png_free(png_ptr, new_key);
+
+ buf[0] = (png_byte)compression;
+ /* write compression */
+ png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1);
+ /* write the compressed data */
+ png_write_compressed_data_out(png_ptr, &comp);
+
+ /* close the chunk */
+ png_write_chunk_end(png_ptr);
+}
+#endif
+
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+/* write an iTXt chunk */
+void /* PRIVATE */
+png_write_iTXt(png_structp png_ptr, int compression, png_charp key,
+ png_charp lang, png_charp lang_key, png_charp text)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_iTXt;
+#endif
+ png_size_t lang_len, key_len, lang_key_len, text_len;
+ png_charp new_lang, new_key;
+ png_byte cbuf[2];
+ compression_state comp;
+
+ png_debug(1, "in png_write_iTXt\n");
+
+ comp.num_output_ptr = 0;
+ comp.max_output_ptr = 0;
+ comp.output_ptr = NULL;
+ comp.input = NULL;
+
+ if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
+ {
+ png_warning(png_ptr, "Empty keyword in iTXt chunk");
+ return;
+ }
+ if (lang == NULL || (lang_len = png_check_keyword(png_ptr, lang, &new_lang))==0)
+ {
+ png_warning(png_ptr, "Empty language field in iTXt chunk");
+ new_lang = NULL;
+ lang_len = 0;
+ }
+
+ if (lang_key == NULL)
+ lang_key_len = 0;
+ else
+ lang_key_len = png_strlen(lang_key);
+
+ if (text == NULL)
+ text_len = 0;
+ else
+ text_len = png_strlen(text);
+
+ /* compute the compressed data; do it now for the length */
+ text_len = png_text_compress(png_ptr, text, text_len, compression-2,
+ &comp);
+
+
+ /* make sure we include the compression flag, the compression byte,
+ * and the NULs after the key, lang, and lang_key parts */
+
+ png_write_chunk_start(png_ptr, png_iTXt,
+ (png_uint_32)(
+ 5 /* comp byte, comp flag, terminators for key, lang and lang_key */
+ + key_len
+ + lang_len
+ + lang_key_len
+ + text_len));
+
+ /*
+ * We leave it to the application to meet PNG-1.0 requirements on the
+ * contents of the text. PNG-1.0 through PNG-1.2 discourage the use of
+ * any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them.
+ * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG.
+ */
+ png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
+
+ /* set the compression flag */
+ if (compression == PNG_ITXT_COMPRESSION_NONE || \
+ compression == PNG_TEXT_COMPRESSION_NONE)
+ cbuf[0] = 0;
+ else /* compression == PNG_ITXT_COMPRESSION_zTXt */
+ cbuf[0] = 1;
+ /* set the compression method */
+ cbuf[1] = 0;
+ png_write_chunk_data(png_ptr, cbuf, 2);
+
+ cbuf[0] = 0;
+ png_write_chunk_data(png_ptr, (new_lang ? (png_bytep)new_lang : cbuf), lang_len + 1);
+ png_write_chunk_data(png_ptr, (lang_key ? (png_bytep)lang_key : cbuf), lang_key_len + 1);
+ png_write_compressed_data_out(png_ptr, &comp);
+
+ png_write_chunk_end(png_ptr);
+ png_free(png_ptr, new_key);
+ if (new_lang)
+ png_free(png_ptr, new_lang);
+}
+#endif
+
+#if defined(PNG_WRITE_oFFs_SUPPORTED)
+/* write the oFFs chunk */
+void /* PRIVATE */
+png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset,
+ int unit_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_oFFs;
+#endif
+ png_byte buf[9];
+
+ png_debug(1, "in png_write_oFFs\n");
+ if (unit_type >= PNG_OFFSET_LAST)
+ png_warning(png_ptr, "Unrecognized unit type for oFFs chunk");
+
+ png_save_int_32(buf, x_offset);
+ png_save_int_32(buf + 4, y_offset);
+ buf[8] = (png_byte)unit_type;
+
+ png_write_chunk(png_ptr, png_oFFs, buf, (png_size_t)9);
+}
+#endif
+#if defined(PNG_WRITE_pCAL_SUPPORTED)
+/* write the pCAL chunk (described in the PNG extensions document) */
+void /* PRIVATE */
+png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
+ png_int_32 X1, int type, int nparams, png_charp units, png_charpp params)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_pCAL;
+#endif
+ png_size_t purpose_len, units_len, total_len;
+ png_uint_32p params_len;
+ png_byte buf[10];
+ png_charp new_purpose;
+ int i;
+
+ png_debug1(1, "in png_write_pCAL (%d parameters)\n", nparams);
+ if (type >= PNG_EQUATION_LAST)
+ png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
+
+ purpose_len = png_check_keyword(png_ptr, purpose, &new_purpose) + 1;
+ png_debug1(3, "pCAL purpose length = %d\n", (int)purpose_len);
+ units_len = png_strlen(units) + (nparams == 0 ? 0 : 1);
+ png_debug1(3, "pCAL units length = %d\n", (int)units_len);
+ total_len = purpose_len + units_len + 10;
+
+ params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams
+ *png_sizeof(png_uint_32)));
+
+ /* Find the length of each parameter, making sure we don't count the
+ null terminator for the last parameter. */
+ for (i = 0; i < nparams; i++)
+ {
+ params_len[i] = png_strlen(params[i]) + (i == nparams - 1 ? 0 : 1);
+ png_debug2(3, "pCAL parameter %d length = %lu\n", i, params_len[i]);
+ total_len += (png_size_t)params_len[i];
+ }
+
+ png_debug1(3, "pCAL total length = %d\n", (int)total_len);
+ png_write_chunk_start(png_ptr, png_pCAL, (png_uint_32)total_len);
+ png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
+ png_save_int_32(buf, X0);
+ png_save_int_32(buf + 4, X1);
+ buf[8] = (png_byte)type;
+ buf[9] = (png_byte)nparams;
+ png_write_chunk_data(png_ptr, buf, (png_size_t)10);
+ png_write_chunk_data(png_ptr, (png_bytep)units, (png_size_t)units_len);
+
+ png_free(png_ptr, new_purpose);
+
+ for (i = 0; i < nparams; i++)
+ {
+ png_write_chunk_data(png_ptr, (png_bytep)params[i],
+ (png_size_t)params_len[i]);
+ }
+
+ png_free(png_ptr, params_len);
+ png_write_chunk_end(png_ptr);
+}
+#endif
+
+#if defined(PNG_WRITE_sCAL_SUPPORTED)
+/* write the sCAL chunk */
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
+void /* PRIVATE */
+png_write_sCAL(png_structp png_ptr, int unit, double width, double height)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_sCAL;
+#endif
+ char buf[64];
+ png_size_t total_len;
+
+ png_debug(1, "in png_write_sCAL\n");
+
+ buf[0] = (char)unit;
+#if defined(_WIN32_WCE)
+/* sprintf() function is not supported on WindowsCE */
+ {
+ wchar_t wc_buf[32];
+ size_t wc_len;
+ swprintf(wc_buf, TEXT("%12.12e"), width);
+ wc_len = wcslen(wc_buf);
+ WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, buf + 1, wc_len, NULL, NULL);
+ total_len = wc_len + 2;
+ swprintf(wc_buf, TEXT("%12.12e"), height);
+ wc_len = wcslen(wc_buf);
+ WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, buf + total_len, wc_len,
+ NULL, NULL);
+ total_len += wc_len;
+ }
+#else
+ png_snprintf(buf + 1, 63, "%12.12e", width);
+ total_len = 1 + png_strlen(buf + 1) + 1;
+ png_snprintf(buf + total_len, 64-total_len, "%12.12e", height);
+ total_len += png_strlen(buf + total_len);
+#endif
+
+ png_debug1(3, "sCAL total length = %u\n", (unsigned int)total_len);
+ png_write_chunk(png_ptr, png_sCAL, (png_bytep)buf, total_len);
+}
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width,
+ png_charp height)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_sCAL;
+#endif
+ png_byte buf[64];
+ png_size_t wlen, hlen, total_len;
+
+ png_debug(1, "in png_write_sCAL_s\n");
+
+ wlen = png_strlen(width);
+ hlen = png_strlen(height);
+ total_len = wlen + hlen + 2;
+ if (total_len > 64)
+ {
+ png_warning(png_ptr, "Can't write sCAL (buffer too small)");
+ return;
+ }
+
+ buf[0] = (png_byte)unit;
+ png_memcpy(buf + 1, width, wlen + 1); /* append the '\0' here */
+ png_memcpy(buf + wlen + 2, height, hlen); /* do NOT append the '\0' here */
+
+ png_debug1(3, "sCAL total length = %u\n", (unsigned int)total_len);
+ png_write_chunk(png_ptr, png_sCAL, buf, total_len);
+}
+#endif
+#endif
+#endif
+
+#if defined(PNG_WRITE_pHYs_SUPPORTED)
+/* write the pHYs chunk */
+void /* PRIVATE */
+png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
+ png_uint_32 y_pixels_per_unit,
+ int unit_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_pHYs;
+#endif
+ png_byte buf[9];
+
+ png_debug(1, "in png_write_pHYs\n");
+ if (unit_type >= PNG_RESOLUTION_LAST)
+ png_warning(png_ptr, "Unrecognized unit type for pHYs chunk");
+
+ png_save_uint_32(buf, x_pixels_per_unit);
+ png_save_uint_32(buf + 4, y_pixels_per_unit);
+ buf[8] = (png_byte)unit_type;
+
+ png_write_chunk(png_ptr, png_pHYs, buf, (png_size_t)9);
+}
+#endif
+
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+/* Write the tIME chunk. Use either png_convert_from_struct_tm()
+ * or png_convert_from_time_t(), or fill in the structure yourself.
+ */
+void /* PRIVATE */
+png_write_tIME(png_structp png_ptr, png_timep mod_time)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_tIME;
+#endif
+ png_byte buf[7];
+
+ png_debug(1, "in png_write_tIME\n");
+ if (mod_time->month > 12 || mod_time->month < 1 ||
+ mod_time->day > 31 || mod_time->day < 1 ||
+ mod_time->hour > 23 || mod_time->second > 60)
+ {
+ png_warning(png_ptr, "Invalid time specified for tIME chunk");
+ return;
+ }
+
+ png_save_uint_16(buf, mod_time->year);
+ buf[2] = mod_time->month;
+ buf[3] = mod_time->day;
+ buf[4] = mod_time->hour;
+ buf[5] = mod_time->minute;
+ buf[6] = mod_time->second;
+
+ png_write_chunk(png_ptr, png_tIME, buf, (png_size_t)7);
+}
+#endif
+
+/* initializes the row writing capability of libpng */
+void /* PRIVATE */
+png_write_start_row(png_structp png_ptr)
+{
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+#ifdef PNG_USE_LOCAL_ARRAYS
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+ /* start of interlace block */
+ int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+ /* offset to next interlace block */
+ int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+ /* start of interlace block in the y direction */
+ int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+ /* offset to next interlace block in the y direction */
+ int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+#endif
+
+ png_size_t buf_size;
+
+ png_debug(1, "in png_write_start_row\n");
+ buf_size = (png_size_t)(PNG_ROWBYTES(
+ png_ptr->usr_channels*png_ptr->usr_bit_depth,png_ptr->width)+1);
+
+ /* set up row buffer */
+ png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
+ png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
+
+#ifndef PNG_NO_WRITE_FILTERING
+ /* set up filtering buffer, if using this filter */
+ if (png_ptr->do_filter & PNG_FILTER_SUB)
+ {
+ png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
+ }
+
+ /* We only need to keep the previous row if we are using one of these. */
+ if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
+ {
+ /* set up previous row buffer */
+ png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
+ png_memset(png_ptr->prev_row, 0, buf_size);
+
+ if (png_ptr->do_filter & PNG_FILTER_UP)
+ {
+ png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
+ }
+
+ if (png_ptr->do_filter & PNG_FILTER_AVG)
+ {
+ png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
+ }
+
+ if (png_ptr->do_filter & PNG_FILTER_PAETH)
+ {
+ png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
+ (png_ptr->rowbytes + 1));
+ png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
+ }
+#endif /* PNG_NO_WRITE_FILTERING */
+ }
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+ /* if interlaced, we need to set up width and height of pass */
+ if (png_ptr->interlaced)
+ {
+ if (!(png_ptr->transformations & PNG_INTERLACE))
+ {
+ png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
+ png_pass_ystart[0]) / png_pass_yinc[0];
+ png_ptr->usr_width = (png_ptr->width + png_pass_inc[0] - 1 -
+ png_pass_start[0]) / png_pass_inc[0];
+ }
+ else
+ {
+ png_ptr->num_rows = png_ptr->height;
+ png_ptr->usr_width = png_ptr->width;
+ }
+ }
+ else
+#endif
+ {
+ png_ptr->num_rows = png_ptr->height;
+ png_ptr->usr_width = png_ptr->width;
+ }
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+}
+
+/* Internal use only. Called when finished processing a row of data. */
+void /* PRIVATE */
+png_write_finish_row(png_structp png_ptr)
+{
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+#ifdef PNG_USE_LOCAL_ARRAYS
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+ /* start of interlace block */
+ int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+ /* offset to next interlace block */
+ int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+ /* start of interlace block in the y direction */
+ int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+ /* offset to next interlace block in the y direction */
+ int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+#endif
+
+ int ret;
+
+ png_debug(1, "in png_write_finish_row\n");
+ /* next row */
+ png_ptr->row_number++;
+
+ /* see if we are done */
+ if (png_ptr->row_number < png_ptr->num_rows)
+ return;
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+ /* if interlaced, go to next pass */
+ if (png_ptr->interlaced)
+ {
+ png_ptr->row_number = 0;
+ if (png_ptr->transformations & PNG_INTERLACE)
+ {
+ png_ptr->pass++;
+ }
+ else
+ {
+ /* loop until we find a non-zero width or height pass */
+ do
+ {
+ png_ptr->pass++;
+ if (png_ptr->pass >= 7)
+ break;
+ png_ptr->usr_width = (png_ptr->width +
+ png_pass_inc[png_ptr->pass] - 1 -
+ png_pass_start[png_ptr->pass]) /
+ png_pass_inc[png_ptr->pass];
+ png_ptr->num_rows = (png_ptr->height +
+ png_pass_yinc[png_ptr->pass] - 1 -
+ png_pass_ystart[png_ptr->pass]) /
+ png_pass_yinc[png_ptr->pass];
+ if (png_ptr->transformations & PNG_INTERLACE)
+ break;
+ } while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
+
+ }
+
+ /* reset the row above the image for the next pass */
+ if (png_ptr->pass < 7)
+ {
+ if (png_ptr->prev_row != NULL)
+ png_memset(png_ptr->prev_row, 0,
+ (png_size_t)(PNG_ROWBYTES(png_ptr->usr_channels*
+ png_ptr->usr_bit_depth,png_ptr->width))+1);
+ return;
+ }
+ }
+#endif
+
+ /* if we get here, we've just written the last row, so we need
+ to flush the compressor */
+ do
+ {
+ /* tell the compressor we are done */
+ ret = deflate(&png_ptr->zstream, Z_FINISH);
+ /* check for an error */
+ if (ret == Z_OK)
+ {
+ /* check to see if we need more room */
+ if (!(png_ptr->zstream.avail_out))
+ {
+ png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ }
+ }
+ else if (ret != Z_STREAM_END)
+ {
+ if (png_ptr->zstream.msg != NULL)
+ png_error(png_ptr, png_ptr->zstream.msg);
+ else
+ png_error(png_ptr, "zlib error");
+ }
+ } while (ret != Z_STREAM_END);
+
+ /* write any extra space */
+ if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
+ {
+ png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size -
+ png_ptr->zstream.avail_out);
+ }
+
+ deflateReset(&png_ptr->zstream);
+ png_ptr->zstream.data_type = Z_BINARY;
+}
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* Pick out the correct pixels for the interlace pass.
+ * The basic idea here is to go through the row with a source
+ * pointer and a destination pointer (sp and dp), and copy the
+ * correct pixels for the pass. As the row gets compacted,
+ * sp will always be >= dp, so we should never overwrite anything.
+ * See the default: case for the easiest code to understand.
+ */
+void /* PRIVATE */
+png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+ /* start of interlace block */
+ int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+ /* offset to next interlace block */
+ int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+
+ png_debug(1, "in png_do_write_interlace\n");
+ /* we don't have to do anything on the last pass (6) */
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (row != NULL && row_info != NULL && pass < 6)
+#else
+ if (pass < 6)
+#endif
+ {
+ /* each pixel depth is handled separately */
+ switch (row_info->pixel_depth)
+ {
+ case 1:
+ {
+ png_bytep sp;
+ png_bytep dp;
+ int shift;
+ int d;
+ int value;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ dp = row;
+ d = 0;
+ shift = 7;
+ for (i = png_pass_start[pass]; i < row_width;
+ i += png_pass_inc[pass])
+ {
+ sp = row + (png_size_t)(i >> 3);
+ value = (int)(*sp >> (7 - (int)(i & 0x07))) & 0x01;
+ d |= (value << shift);
+
+ if (shift == 0)
+ {
+ shift = 7;
+ *dp++ = (png_byte)d;
+ d = 0;
+ }
+ else
+ shift--;
+
+ }
+ if (shift != 7)
+ *dp = (png_byte)d;
+ break;
+ }
+ case 2:
+ {
+ png_bytep sp;
+ png_bytep dp;
+ int shift;
+ int d;
+ int value;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ dp = row;
+ shift = 6;
+ d = 0;
+ for (i = png_pass_start[pass]; i < row_width;
+ i += png_pass_inc[pass])
+ {
+ sp = row + (png_size_t)(i >> 2);
+ value = (*sp >> ((3 - (int)(i & 0x03)) << 1)) & 0x03;
+ d |= (value << shift);
+
+ if (shift == 0)
+ {
+ shift = 6;
+ *dp++ = (png_byte)d;
+ d = 0;
+ }
+ else
+ shift -= 2;
+ }
+ if (shift != 6)
+ *dp = (png_byte)d;
+ break;
+ }
+ case 4:
+ {
+ png_bytep sp;
+ png_bytep dp;
+ int shift;
+ int d;
+ int value;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+
+ dp = row;
+ shift = 4;
+ d = 0;
+ for (i = png_pass_start[pass]; i < row_width;
+ i += png_pass_inc[pass])
+ {
+ sp = row + (png_size_t)(i >> 1);
+ value = (*sp >> ((1 - (int)(i & 0x01)) << 2)) & 0x0f;
+ d |= (value << shift);
+
+ if (shift == 0)
+ {
+ shift = 4;
+ *dp++ = (png_byte)d;
+ d = 0;
+ }
+ else
+ shift -= 4;
+ }
+ if (shift != 4)
+ *dp = (png_byte)d;
+ break;
+ }
+ default:
+ {
+ png_bytep sp;
+ png_bytep dp;
+ png_uint_32 i;
+ png_uint_32 row_width = row_info->width;
+ png_size_t pixel_bytes;
+
+ /* start at the beginning */
+ dp = row;
+ /* find out how many bytes each pixel takes up */
+ pixel_bytes = (row_info->pixel_depth >> 3);
+ /* loop through the row, only looking at the pixels that
+ matter */
+ for (i = png_pass_start[pass]; i < row_width;
+ i += png_pass_inc[pass])
+ {
+ /* find out where the original pixel is */
+ sp = row + (png_size_t)i * pixel_bytes;
+ /* move the pixel */
+ if (dp != sp)
+ png_memcpy(dp, sp, pixel_bytes);
+ /* next pixel */
+ dp += pixel_bytes;
+ }
+ break;
+ }
+ }
+ /* set new row width */
+ row_info->width = (row_info->width +
+ png_pass_inc[pass] - 1 -
+ png_pass_start[pass]) /
+ png_pass_inc[pass];
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+ row_info->width);
+ }
+}
+#endif
+
+/* This filters the row, chooses which filter to use, if it has not already
+ * been specified by the application, and then writes the row out with the
+ * chosen filter.
+ */
+#define PNG_MAXSUM (((png_uint_32)(-1)) >> 1)
+#define PNG_HISHIFT 10
+#define PNG_LOMASK ((png_uint_32)0xffffL)
+#define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT))
+void /* PRIVATE */
+png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
+{
+ png_bytep best_row;
+#ifndef PNG_NO_WRITE_FILTER
+ png_bytep prev_row, row_buf;
+ png_uint_32 mins, bpp;
+ png_byte filter_to_do = png_ptr->do_filter;
+ png_uint_32 row_bytes = row_info->rowbytes;
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ int num_p_filters = (int)png_ptr->num_prev_filters;
+#endif
+
+ png_debug(1, "in png_write_find_filter\n");
+ /* find out how many bytes offset each pixel is */
+ bpp = (row_info->pixel_depth + 7) >> 3;
+
+ prev_row = png_ptr->prev_row;
+#endif
+ best_row = png_ptr->row_buf;
+#ifndef PNG_NO_WRITE_FILTER
+ row_buf = best_row;
+ mins = PNG_MAXSUM;
+
+ /* The prediction method we use is to find which method provides the
+ * smallest value when summing the absolute values of the distances
+ * from zero, using anything >= 128 as negative numbers. This is known
+ * as the "minimum sum of absolute differences" heuristic. Other
+ * heuristics are the "weighted minimum sum of absolute differences"
+ * (experimental and can in theory improve compression), and the "zlib
+ * predictive" method (not implemented yet), which does test compressions
+ * of lines using different filter methods, and then chooses the
+ * (series of) filter(s) that give minimum compressed data size (VERY
+ * computationally expensive).
+ *
+ * GRR 980525: consider also
+ * (1) minimum sum of absolute differences from running average (i.e.,
+ * keep running sum of non-absolute differences & count of bytes)
+ * [track dispersion, too? restart average if dispersion too large?]
+ * (1b) minimum sum of absolute differences from sliding average, probably
+ * with window size <= deflate window (usually 32K)
+ * (2) minimum sum of squared differences from zero or running average
+ * (i.e., ~ root-mean-square approach)
+ */
+
+
+ /* We don't need to test the 'no filter' case if this is the only filter
+ * that has been chosen, as it doesn't actually do anything to the data.
+ */
+ if ((filter_to_do & PNG_FILTER_NONE) &&
+ filter_to_do != PNG_FILTER_NONE)
+ {
+ png_bytep rp;
+ png_uint_32 sum = 0;
+ png_uint_32 i;
+ int v;
+
+ for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
+ {
+ v = *rp;
+ sum += (v < 128) ? v : 256 - v;
+ }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ png_uint_32 sumhi, sumlo;
+ int j;
+ sumlo = sum & PNG_LOMASK;
+ sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */
+
+ /* Reduce the sum if we match any of the previous rows */
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
+ {
+ sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ /* Factor in the cost of this filter (this is here for completeness,
+ * but it makes no sense to have a "cost" for the NONE filter, as
+ * it has the minimum possible computational cost - none).
+ */
+ sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
+ PNG_COST_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
+ PNG_COST_SHIFT;
+
+ if (sumhi > PNG_HIMASK)
+ sum = PNG_MAXSUM;
+ else
+ sum = (sumhi << PNG_HISHIFT) + sumlo;
+ }
+#endif
+ mins = sum;
+ }
+
+ /* sub filter */
+ if (filter_to_do == PNG_FILTER_SUB)
+ /* it's the only filter so no testing is needed */
+ {
+ png_bytep rp, lp, dp;
+ png_uint_32 i;
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
+ i++, rp++, dp++)
+ {
+ *dp = *rp;
+ }
+ for (lp = row_buf + 1; i < row_bytes;
+ i++, rp++, lp++, dp++)
+ {
+ *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+ }
+ best_row = png_ptr->sub_row;
+ }
+
+ else if (filter_to_do & PNG_FILTER_SUB)
+ {
+ png_bytep rp, dp, lp;
+ png_uint_32 sum = 0, lmins = mins;
+ png_uint_32 i;
+ int v;
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ /* We temporarily increase the "minimum sum" by the factor we
+ * would reduce the sum of this filter, so that we can do the
+ * early exit comparison without scaling the sum each time.
+ */
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 lmhi, lmlo;
+ lmlo = lmins & PNG_LOMASK;
+ lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
+ {
+ lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+ PNG_COST_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+ PNG_COST_SHIFT;
+
+ if (lmhi > PNG_HIMASK)
+ lmins = PNG_MAXSUM;
+ else
+ lmins = (lmhi << PNG_HISHIFT) + lmlo;
+ }
+#endif
+
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
+ i++, rp++, dp++)
+ {
+ v = *dp = *rp;
+
+ sum += (v < 128) ? v : 256 - v;
+ }
+ for (lp = row_buf + 1; i < row_bytes;
+ i++, rp++, lp++, dp++)
+ {
+ v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+
+ sum += (v < 128) ? v : 256 - v;
+
+ if (sum > lmins) /* We are already worse, don't continue. */
+ break;
+ }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 sumhi, sumlo;
+ sumlo = sum & PNG_LOMASK;
+ sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
+ {
+ sumlo = (sumlo * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ sumhi = (sumhi * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+ PNG_COST_SHIFT;
+ sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+ PNG_COST_SHIFT;
+
+ if (sumhi > PNG_HIMASK)
+ sum = PNG_MAXSUM;
+ else
+ sum = (sumhi << PNG_HISHIFT) + sumlo;
+ }
+#endif
+
+ if (sum < mins)
+ {
+ mins = sum;
+ best_row = png_ptr->sub_row;
+ }
+ }
+
+ /* up filter */
+ if (filter_to_do == PNG_FILTER_UP)
+ {
+ png_bytep rp, dp, pp;
+ png_uint_32 i;
+
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
+ pp = prev_row + 1; i < row_bytes;
+ i++, rp++, pp++, dp++)
+ {
+ *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
+ }
+ best_row = png_ptr->up_row;
+ }
+
+ else if (filter_to_do & PNG_FILTER_UP)
+ {
+ png_bytep rp, dp, pp;
+ png_uint_32 sum = 0, lmins = mins;
+ png_uint_32 i;
+ int v;
+
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 lmhi, lmlo;
+ lmlo = lmins & PNG_LOMASK;
+ lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
+ {
+ lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
+ PNG_COST_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
+ PNG_COST_SHIFT;
+
+ if (lmhi > PNG_HIMASK)
+ lmins = PNG_MAXSUM;
+ else
+ lmins = (lmhi << PNG_HISHIFT) + lmlo;
+ }
+#endif
+
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
+ pp = prev_row + 1; i < row_bytes; i++)
+ {
+ v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+
+ sum += (v < 128) ? v : 256 - v;
+
+ if (sum > lmins) /* We are already worse, don't continue. */
+ break;
+ }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 sumhi, sumlo;
+ sumlo = sum & PNG_LOMASK;
+ sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
+ {
+ sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
+ PNG_COST_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
+ PNG_COST_SHIFT;
+
+ if (sumhi > PNG_HIMASK)
+ sum = PNG_MAXSUM;
+ else
+ sum = (sumhi << PNG_HISHIFT) + sumlo;
+ }
+#endif
+
+ if (sum < mins)
+ {
+ mins = sum;
+ best_row = png_ptr->up_row;
+ }
+ }
+
+ /* avg filter */
+ if (filter_to_do == PNG_FILTER_AVG)
+ {
+ png_bytep rp, dp, pp, lp;
+ png_uint_32 i;
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
+ pp = prev_row + 1; i < bpp; i++)
+ {
+ *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
+ }
+ for (lp = row_buf + 1; i < row_bytes; i++)
+ {
+ *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
+ & 0xff);
+ }
+ best_row = png_ptr->avg_row;
+ }
+
+ else if (filter_to_do & PNG_FILTER_AVG)
+ {
+ png_bytep rp, dp, pp, lp;
+ png_uint_32 sum = 0, lmins = mins;
+ png_uint_32 i;
+ int v;
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 lmhi, lmlo;
+ lmlo = lmins & PNG_LOMASK;
+ lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_AVG)
+ {
+ lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
+ PNG_COST_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
+ PNG_COST_SHIFT;
+
+ if (lmhi > PNG_HIMASK)
+ lmins = PNG_MAXSUM;
+ else
+ lmins = (lmhi << PNG_HISHIFT) + lmlo;
+ }
+#endif
+
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
+ pp = prev_row + 1; i < bpp; i++)
+ {
+ v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
+
+ sum += (v < 128) ? v : 256 - v;
+ }
+ for (lp = row_buf + 1; i < row_bytes; i++)
+ {
+ v = *dp++ =
+ (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) & 0xff);
+
+ sum += (v < 128) ? v : 256 - v;
+
+ if (sum > lmins) /* We are already worse, don't continue. */
+ break;
+ }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 sumhi, sumlo;
+ sumlo = sum & PNG_LOMASK;
+ sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
+ {
+ sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
+ PNG_COST_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
+ PNG_COST_SHIFT;
+
+ if (sumhi > PNG_HIMASK)
+ sum = PNG_MAXSUM;
+ else
+ sum = (sumhi << PNG_HISHIFT) + sumlo;
+ }
+#endif
+
+ if (sum < mins)
+ {
+ mins = sum;
+ best_row = png_ptr->avg_row;
+ }
+ }
+
+ /* Paeth filter */
+ if (filter_to_do == PNG_FILTER_PAETH)
+ {
+ png_bytep rp, dp, pp, cp, lp;
+ png_uint_32 i;
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
+ pp = prev_row + 1; i < bpp; i++)
+ {
+ *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+ }
+
+ for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++)
+ {
+ int a, b, c, pa, pb, pc, p;
+
+ b = *pp++;
+ c = *cp++;
+ a = *lp++;
+
+ p = b - c;
+ pc = a - c;
+
+#ifdef PNG_USE_ABS
+ pa = abs(p);
+ pb = abs(pc);
+ pc = abs(p + pc);
+#else
+ pa = p < 0 ? -p : p;
+ pb = pc < 0 ? -pc : pc;
+ pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+ p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+
+ *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
+ }
+ best_row = png_ptr->paeth_row;
+ }
+
+ else if (filter_to_do & PNG_FILTER_PAETH)
+ {
+ png_bytep rp, dp, pp, cp, lp;
+ png_uint_32 sum = 0, lmins = mins;
+ png_uint_32 i;
+ int v;
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 lmhi, lmlo;
+ lmlo = lmins & PNG_LOMASK;
+ lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
+ {
+ lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+ PNG_COST_SHIFT;
+ lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+ PNG_COST_SHIFT;
+
+ if (lmhi > PNG_HIMASK)
+ lmins = PNG_MAXSUM;
+ else
+ lmins = (lmhi << PNG_HISHIFT) + lmlo;
+ }
+#endif
+
+ for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
+ pp = prev_row + 1; i < bpp; i++)
+ {
+ v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+
+ sum += (v < 128) ? v : 256 - v;
+ }
+
+ for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++)
+ {
+ int a, b, c, pa, pb, pc, p;
+
+ b = *pp++;
+ c = *cp++;
+ a = *lp++;
+
+#ifndef PNG_SLOW_PAETH
+ p = b - c;
+ pc = a - c;
+#ifdef PNG_USE_ABS
+ pa = abs(p);
+ pb = abs(pc);
+ pc = abs(p + pc);
+#else
+ pa = p < 0 ? -p : p;
+ pb = pc < 0 ? -pc : pc;
+ pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+ p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+#else /* PNG_SLOW_PAETH */
+ p = a + b - c;
+ pa = abs(p - a);
+ pb = abs(p - b);
+ pc = abs(p - c);
+ if (pa <= pb && pa <= pc)
+ p = a;
+ else if (pb <= pc)
+ p = b;
+ else
+ p = c;
+#endif /* PNG_SLOW_PAETH */
+
+ v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
+
+ sum += (v < 128) ? v : 256 - v;
+
+ if (sum > lmins) /* We are already worse, don't continue. */
+ break;
+ }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+ {
+ int j;
+ png_uint_32 sumhi, sumlo;
+ sumlo = sum & PNG_LOMASK;
+ sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+ for (j = 0; j < num_p_filters; j++)
+ {
+ if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
+ {
+ sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+ PNG_WEIGHT_SHIFT;
+ }
+ }
+
+ sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+ PNG_COST_SHIFT;
+ sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+ PNG_COST_SHIFT;
+
+ if (sumhi > PNG_HIMASK)
+ sum = PNG_MAXSUM;
+ else
+ sum = (sumhi << PNG_HISHIFT) + sumlo;
+ }
+#endif
+
+ if (sum < mins)
+ {
+ best_row = png_ptr->paeth_row;
+ }
+ }
+#endif /* PNG_NO_WRITE_FILTER */
+ /* Do the actual writing of the filtered row data from the chosen filter. */
+
+ png_write_filtered_row(png_ptr, best_row);
+
+#ifndef PNG_NO_WRITE_FILTER
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+ /* Save the type of filter we picked this time for future calculations */
+ if (png_ptr->num_prev_filters > 0)
+ {
+ int j;
+ for (j = 1; j < num_p_filters; j++)
+ {
+ png_ptr->prev_filters[j] = png_ptr->prev_filters[j - 1];
+ }
+ png_ptr->prev_filters[j] = best_row[0];
+ }
+#endif
+#endif /* PNG_NO_WRITE_FILTER */
+}
+
+
+/* Do the actual writing of a previously filtered row. */
+void /* PRIVATE */
+png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row)
+{
+ png_debug(1, "in png_write_filtered_row\n");
+ png_debug1(2, "filter = %d\n", filtered_row[0]);
+ /* set up the zlib input buffer */
+
+ png_ptr->zstream.next_in = filtered_row;
+ png_ptr->zstream.avail_in = (uInt)png_ptr->row_info.rowbytes + 1;
+ /* repeat until we have compressed all the data */
+ do
+ {
+ int ret; /* return of zlib */
+
+ /* compress the data */
+ ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
+ /* check for compression errors */
+ if (ret != Z_OK)
+ {
+ if (png_ptr->zstream.msg != NULL)
+ png_error(png_ptr, png_ptr->zstream.msg);
+ else
+ png_error(png_ptr, "zlib error");
+ }
+
+ /* see if it is time to write another IDAT */
+ if (!(png_ptr->zstream.avail_out))
+ {
+ /* write the IDAT and reset the zlib output buffer */
+ png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ }
+ /* repeat until all data has been compressed */
+ } while (png_ptr->zstream.avail_in);
+
+ /* swap the current and previous rows */
+ if (png_ptr->prev_row != NULL)
+ {
+ png_bytep tptr;
+
+ tptr = png_ptr->prev_row;
+ png_ptr->prev_row = png_ptr->row_buf;
+ png_ptr->row_buf = tptr;
+ }
+
+ /* finish row - updates counters and flushes zlib if last row */
+ png_write_finish_row(png_ptr);
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+ png_ptr->flush_rows++;
+
+ if (png_ptr->flush_dist > 0 &&
+ png_ptr->flush_rows >= png_ptr->flush_dist)
+ {
+ png_write_flush(png_ptr);
+ }
+#endif
+}
+#endif /* PNG_WRITE_SUPPORTED */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 00:49:27 +0000