diff options
Diffstat (limited to 'src/libtiff/tif_strip.c')
| -rw-r--r-- | src/libtiff/tif_strip.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/src/libtiff/tif_strip.c b/src/libtiff/tif_strip.c new file mode 100644 index 0000000..e6a0fb7 --- /dev/null +++ b/src/libtiff/tif_strip.c @@ -0,0 +1,294 @@ +/* $Id: tif_strip.c,v 1.1 2008/10/17 06:16:07 scuri Exp $ */ + +/* + * Copyright (c) 1991-1997 Sam Leffler + * Copyright (c) 1991-1997 Silicon Graphics, Inc. + * + * Permission to use, copy, modify, distribute, and sell this software and + * its documentation for any purpose is hereby granted without fee, provided + * that (i) the above copyright notices and this permission notice appear in + * all copies of the software and related documentation, and (ii) the names of + * Sam Leffler and Silicon Graphics may not be used in any advertising or + * publicity relating to the software without the specific, prior written + * permission of Sam Leffler and Silicon Graphics. + * + * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, + * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY + * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. + * + * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR + * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, + * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, + * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF + * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE + * OF THIS SOFTWARE. + */ + +/* + * TIFF Library. + * + * Strip-organized Image Support Routines. + */ +#include "tiffiop.h" + +static uint32 +summarize(TIFF* tif, size_t summand1, size_t summand2, const char* where) +{ + /* + * XXX: We are using casting to uint32 here, bacause sizeof(size_t) + * may be larger than sizeof(uint32) on 64-bit architectures. + */ + uint32 bytes = summand1 + summand2; + + if (bytes - summand1 != summand2) { + TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Integer overflow in %s", where); + bytes = 0; + } + + return (bytes); +} + +static uint32 +multiply(TIFF* tif, size_t nmemb, size_t elem_size, const char* where) +{ + uint32 bytes = nmemb * elem_size; + + if (elem_size && bytes / elem_size != nmemb) { + TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Integer overflow in %s", where); + bytes = 0; + } + + return (bytes); +} + +/* + * Compute which strip a (row,sample) value is in. + */ +tstrip_t +TIFFComputeStrip(TIFF* tif, uint32 row, tsample_t sample) +{ + TIFFDirectory *td = &tif->tif_dir; + tstrip_t strip; + + strip = row / td->td_rowsperstrip; + if (td->td_planarconfig == PLANARCONFIG_SEPARATE) { + if (sample >= td->td_samplesperpixel) { + TIFFErrorExt(tif->tif_clientdata, tif->tif_name, + "%lu: Sample out of range, max %lu", + (unsigned long) sample, (unsigned long) td->td_samplesperpixel); + return ((tstrip_t) 0); + } + strip += sample*td->td_stripsperimage; + } + return (strip); +} + +/* + * Compute how many strips are in an image. + */ +tstrip_t +TIFFNumberOfStrips(TIFF* tif) +{ + TIFFDirectory *td = &tif->tif_dir; + tstrip_t nstrips; + + nstrips = (td->td_rowsperstrip == (uint32) -1 ? 1 : + TIFFhowmany(td->td_imagelength, td->td_rowsperstrip)); + if (td->td_planarconfig == PLANARCONFIG_SEPARATE) + nstrips = multiply(tif, nstrips, td->td_samplesperpixel, + "TIFFNumberOfStrips"); + return (nstrips); +} + +/* + * Compute the # bytes in a variable height, row-aligned strip. + */ +tsize_t +TIFFVStripSize(TIFF* tif, uint32 nrows) +{ + TIFFDirectory *td = &tif->tif_dir; + + if (nrows == (uint32) -1) + nrows = td->td_imagelength; + if (td->td_planarconfig == PLANARCONFIG_CONTIG && + td->td_photometric == PHOTOMETRIC_YCBCR && + !isUpSampled(tif)) { + /* + * Packed YCbCr data contain one Cb+Cr for every + * HorizontalSampling*VerticalSampling Y values. + * Must also roundup width and height when calculating + * since images that are not a multiple of the + * horizontal/vertical subsampling area include + * YCbCr data for the extended image. + */ + uint16 ycbcrsubsampling[2]; + tsize_t w, scanline, samplingarea; + + TIFFGetField( tif, TIFFTAG_YCBCRSUBSAMPLING, + ycbcrsubsampling + 0, + ycbcrsubsampling + 1 ); + + samplingarea = ycbcrsubsampling[0]*ycbcrsubsampling[1]; + if (samplingarea == 0) { + TIFFErrorExt(tif->tif_clientdata, tif->tif_name, + "Invalid YCbCr subsampling"); + return 0; + } + + w = TIFFroundup(td->td_imagewidth, ycbcrsubsampling[0]); + scanline = TIFFhowmany8(multiply(tif, w, td->td_bitspersample, + "TIFFVStripSize")); + nrows = TIFFroundup(nrows, ycbcrsubsampling[1]); + /* NB: don't need TIFFhowmany here 'cuz everything is rounded */ + scanline = multiply(tif, nrows, scanline, "TIFFVStripSize"); + return ((tsize_t) + summarize(tif, scanline, + multiply(tif, 2, scanline / samplingarea, + "TIFFVStripSize"), "TIFFVStripSize")); + } else + return ((tsize_t) multiply(tif, nrows, TIFFScanlineSize(tif), + "TIFFVStripSize")); +} + + +/* + * Compute the # bytes in a raw strip. + */ +tsize_t +TIFFRawStripSize(TIFF* tif, tstrip_t strip) +{ + TIFFDirectory* td = &tif->tif_dir; + tsize_t bytecount = td->td_stripbytecount[strip]; + + if (bytecount <= 0) { + TIFFErrorExt(tif->tif_clientdata, tif->tif_name, + "%lu: Invalid strip byte count, strip %lu", + (unsigned long) bytecount, (unsigned long) strip); + bytecount = (tsize_t) -1; + } + + return bytecount; +} + +/* + * Compute the # bytes in a (row-aligned) strip. + * + * Note that if RowsPerStrip is larger than the + * recorded ImageLength, then the strip size is + * truncated to reflect the actual space required + * to hold the strip. + */ +tsize_t +TIFFStripSize(TIFF* tif) +{ + TIFFDirectory* td = &tif->tif_dir; + uint32 rps = td->td_rowsperstrip; + if (rps > td->td_imagelength) + rps = td->td_imagelength; + return (TIFFVStripSize(tif, rps)); +} + +/* + * Compute a default strip size based on the image + * characteristics and a requested value. If the + * request is <1 then we choose a strip size according + * to certain heuristics. + */ +uint32 +TIFFDefaultStripSize(TIFF* tif, uint32 request) +{ + return (*tif->tif_defstripsize)(tif, request); +} + +uint32 +_TIFFDefaultStripSize(TIFF* tif, uint32 s) +{ + if ((int32) s < 1) { + /* + * If RowsPerStrip is unspecified, try to break the + * image up into strips that are approximately + * STRIP_SIZE_DEFAULT bytes long. + */ + tsize_t scanline = TIFFScanlineSize(tif); + s = (uint32)STRIP_SIZE_DEFAULT / (scanline == 0 ? 1 : scanline); + if (s == 0) /* very wide images */ + s = 1; + } + return (s); +} + +/* + * Return the number of bytes to read/write in a call to + * one of the scanline-oriented i/o routines. Note that + * this number may be 1/samples-per-pixel if data is + * stored as separate planes. + */ +tsize_t +TIFFScanlineSize(TIFF* tif) +{ + TIFFDirectory *td = &tif->tif_dir; + tsize_t scanline; + + if (td->td_planarconfig == PLANARCONFIG_CONTIG) { + if (td->td_photometric == PHOTOMETRIC_YCBCR + && !isUpSampled(tif)) { + uint16 ycbcrsubsampling[2]; + + TIFFGetField(tif, TIFFTAG_YCBCRSUBSAMPLING, + ycbcrsubsampling + 0, + ycbcrsubsampling + 1); + + if (ycbcrsubsampling[0] == 0) { + TIFFErrorExt(tif->tif_clientdata, tif->tif_name, + "Invalid YCbCr subsampling"); + return 0; + } + + scanline = TIFFroundup(td->td_imagewidth, + ycbcrsubsampling[0]); + scanline = TIFFhowmany8(multiply(tif, scanline, + td->td_bitspersample, + "TIFFScanlineSize")); + return ((tsize_t) + summarize(tif, scanline, + multiply(tif, 2, + scanline / ycbcrsubsampling[0], + "TIFFVStripSize"), + "TIFFVStripSize")); + } else { + scanline = multiply(tif, td->td_imagewidth, + td->td_samplesperpixel, + "TIFFScanlineSize"); + } + } else + scanline = td->td_imagewidth; + return ((tsize_t) TIFFhowmany8(multiply(tif, scanline, + td->td_bitspersample, + "TIFFScanlineSize"))); +} + +/* + * Return the number of bytes required to store a complete + * decoded and packed raster scanline (as opposed to the + * I/O size returned by TIFFScanlineSize which may be less + * if data is store as separate planes). + */ +tsize_t +TIFFRasterScanlineSize(TIFF* tif) +{ + TIFFDirectory *td = &tif->tif_dir; + tsize_t scanline; + + scanline = multiply (tif, td->td_bitspersample, td->td_imagewidth, + "TIFFRasterScanlineSize"); + if (td->td_planarconfig == PLANARCONFIG_CONTIG) { + scanline = multiply (tif, scanline, td->td_samplesperpixel, + "TIFFRasterScanlineSize"); + return ((tsize_t) TIFFhowmany8(scanline)); + } else + return ((tsize_t) multiply (tif, TIFFhowmany8(scanline), + td->td_samplesperpixel, + "TIFFRasterScanlineSize")); +} + +/* vim: set ts=8 sts=8 sw=8 noet: */ |