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Diffstat (limited to 'src/libjpeg/jmorecfg.h')
| -rw-r--r-- | src/libjpeg/jmorecfg.h | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/src/libjpeg/jmorecfg.h b/src/libjpeg/jmorecfg.h new file mode 100644 index 0000000..2182f15 --- /dev/null +++ b/src/libjpeg/jmorecfg.h @@ -0,0 +1,364 @@ +/* + * jmorecfg.h + * + * Copyright (C) 1991-1997, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains additional configuration options that customize the + * JPEG software for special applications or support machine-dependent + * optimizations. Most users will not need to touch this file. + */ + + +/* + * Define BITS_IN_JSAMPLE as either + * 8 for 8-bit sample values (the usual setting) + * 12 for 12-bit sample values + * Only 8 and 12 are legal data precisions for lossy JPEG according to the + * JPEG standard, and the IJG code does not support anything else! + * We do not support run-time selection of data precision, sorry. + */ + +#define BITS_IN_JSAMPLE 8 /* use 8 or 12 */ + + +/* + * Maximum number of components (color channels) allowed in JPEG image. + * To meet the letter of the JPEG spec, set this to 255. However, darn + * few applications need more than 4 channels (maybe 5 for CMYK + alpha + * mask). We recommend 10 as a reasonable compromise; use 4 if you are + * really short on memory. (Each allowed component costs a hundred or so + * bytes of storage, whether actually used in an image or not.) + */ + +#define MAX_COMPONENTS 10 /* maximum number of image components */ + + +/* + * Basic data types. + * You may need to change these if you have a machine with unusual data + * type sizes; for example, "char" not 8 bits, "short" not 16 bits, + * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits, + * but it had better be at least 16. + */ + +/* Representation of a single sample (pixel element value). + * We frequently allocate large arrays of these, so it's important to keep + * them small. But if you have memory to burn and access to char or short + * arrays is very slow on your hardware, you might want to change these. + */ + +#if BITS_IN_JSAMPLE == 8 +/* JSAMPLE should be the smallest type that will hold the values 0..255. + * You can use a signed char by having GETJSAMPLE mask it with 0xFF. + */ + +#ifdef HAVE_UNSIGNED_CHAR + +typedef unsigned char JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#else /* not HAVE_UNSIGNED_CHAR */ + +typedef char JSAMPLE; +#ifdef CHAR_IS_UNSIGNED +#define GETJSAMPLE(value) ((int) (value)) +#else +#define GETJSAMPLE(value) ((int) (value) & 0xFF) +#endif /* CHAR_IS_UNSIGNED */ + +#endif /* HAVE_UNSIGNED_CHAR */ + +#define MAXJSAMPLE 255 +#define CENTERJSAMPLE 128 + +#endif /* BITS_IN_JSAMPLE == 8 */ + + +#if BITS_IN_JSAMPLE == 12 +/* JSAMPLE should be the smallest type that will hold the values 0..4095. + * On nearly all machines "short" will do nicely. + */ + +typedef short JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#define MAXJSAMPLE 4095 +#define CENTERJSAMPLE 2048 + +#endif /* BITS_IN_JSAMPLE == 12 */ + + +/* Representation of a DCT frequency coefficient. + * This should be a signed value of at least 16 bits; "short" is usually OK. + * Again, we allocate large arrays of these, but you can change to int + * if you have memory to burn and "short" is really slow. + */ + +typedef short JCOEF; + + +/* Compressed datastreams are represented as arrays of JOCTET. + * These must be EXACTLY 8 bits wide, at least once they are written to + * external storage. Note that when using the stdio data source/destination + * managers, this is also the data type passed to fread/fwrite. + */ + +#ifdef HAVE_UNSIGNED_CHAR + +typedef unsigned char JOCTET; +#define GETJOCTET(value) (value) + +#else /* not HAVE_UNSIGNED_CHAR */ + +typedef char JOCTET; +#ifdef CHAR_IS_UNSIGNED +#define GETJOCTET(value) (value) +#else +#define GETJOCTET(value) ((value) & 0xFF) +#endif /* CHAR_IS_UNSIGNED */ + +#endif /* HAVE_UNSIGNED_CHAR */ + + +/* These typedefs are used for various table entries and so forth. + * They must be at least as wide as specified; but making them too big + * won't cost a huge amount of memory, so we don't provide special + * extraction code like we did for JSAMPLE. (In other words, these + * typedefs live at a different point on the speed/space tradeoff curve.) + */ + +/* UINT8 must hold at least the values 0..255. */ + +#ifdef HAVE_UNSIGNED_CHAR +typedef unsigned char UINT8; +#else /* not HAVE_UNSIGNED_CHAR */ +#ifdef CHAR_IS_UNSIGNED +typedef char UINT8; +#else /* not CHAR_IS_UNSIGNED */ +typedef short UINT8; +#endif /* CHAR_IS_UNSIGNED */ +#endif /* HAVE_UNSIGNED_CHAR */ + +/* UINT16 must hold at least the values 0..65535. */ + +#ifdef HAVE_UNSIGNED_SHORT +typedef unsigned short UINT16; +#else /* not HAVE_UNSIGNED_SHORT */ +typedef unsigned int UINT16; +#endif /* HAVE_UNSIGNED_SHORT */ + +/* INT16 must hold at least the values -32768..32767. */ + +#ifndef XMD_H /* X11/xmd.h correctly defines INT16 */ +typedef short INT16; +#endif + +/* INT32 must hold at least signed 32-bit values. */ + +#ifndef XMD_H /* X11/xmd.h correctly defines INT32 */ +typedef int JINT32; +#define INT32 JINT32 +#endif + +/* Datatype used for image dimensions. The JPEG standard only supports + * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore + * "unsigned int" is sufficient on all machines. However, if you need to + * handle larger images and you don't mind deviating from the spec, you + * can change this datatype. + */ + +typedef unsigned int JDIMENSION; + +#define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */ + + +/* These macros are used in all function definitions and extern declarations. + * You could modify them if you need to change function linkage conventions; + * in particular, you'll need to do that to make the library a Windows DLL. + * Another application is to make all functions global for use with debuggers + * or code profilers that require it. + */ + +/* a function called through method pointers: */ +#define METHODDEF(type) static type +/* a function used only in its module: */ +#define LOCAL(type) static type +/* a function referenced thru EXTERNs: */ +#define GLOBAL(type) type +/* a reference to a GLOBAL function: */ +#define EXTERN(type) extern type + + +/* This macro is used to declare a "method", that is, a function pointer. + * We want to supply prototype parameters if the compiler can cope. + * Note that the arglist parameter must be parenthesized! + * Again, you can customize this if you need special linkage keywords. + */ + +#ifdef HAVE_PROTOTYPES +#define JMETHOD(type,methodname,arglist) type (*methodname) arglist +#else +#define JMETHOD(type,methodname,arglist) type (*methodname) () +#endif + + +/* Here is the pseudo-keyword for declaring pointers that must be "far" + * on 80x86 machines. Most of the specialized coding for 80x86 is handled + * by just saying "FAR *" where such a pointer is needed. In a few places + * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol. + */ + +#ifdef NEED_FAR_POINTERS +#define FAR far +#else +#define FAR +#endif + + +/* + * On a few systems, type boolean and/or its values FALSE, TRUE may appear + * in standard header files. Or you may have conflicts with application- + * specific header files that you want to include together with these files. + * Defining HAVE_BOOLEAN before including jpeglib.h should make it work. + */ + +#ifndef HAVE_BOOLEAN +typedef int boolean; +#endif +#ifndef FALSE /* in case these macros already exist */ +#define FALSE 0 /* values of boolean */ +#endif +#ifndef TRUE +#define TRUE 1 +#endif + + +/* + * The remaining options affect code selection within the JPEG library, + * but they don't need to be visible to most applications using the library. + * To minimize application namespace pollution, the symbols won't be + * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined. + */ + +#ifdef JPEG_INTERNALS +#define JPEG_INTERNAL_OPTIONS +#endif + +#ifdef JPEG_INTERNAL_OPTIONS + + +/* + * These defines indicate whether to include various optional functions. + * Undefining some of these symbols will produce a smaller but less capable + * library. Note that you can leave certain source files out of the + * compilation/linking process if you've #undef'd the corresponding symbols. + * (You may HAVE to do that if your compiler doesn't like null source files.) + */ + +/* Arithmetic coding is unsupported for legal reasons. Complaints to IBM. */ + +/* Capability options common to encoder and decoder: */ + +#define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */ +#define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */ +#define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */ + +/* Encoder capability options: */ + +#undef C_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */ +#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ +#define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ +#define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */ +/* Note: if you selected 12-bit data precision, it is dangerous to turn off + * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit + * precision, so jchuff.c normally uses entropy optimization to compute + * usable tables for higher precision. If you don't want to do optimization, + * you'll have to supply different default Huffman tables. + * The exact same statements apply for progressive JPEG: the default tables + * don't work for progressive mode. (This may get fixed, however.) + */ +#define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */ + +/* Decoder capability options: */ + +#undef D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */ +#define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ +#define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ +#define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */ +#define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */ +#define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */ +#undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */ +#define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */ +#define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */ +#define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */ + +/* more capability options later, no doubt */ + + +/* + * Ordering of RGB data in scanlines passed to or from the application. + * If your application wants to deal with data in the order B,G,R, just + * change these macros. You can also deal with formats such as R,G,B,X + * (one extra byte per pixel) by changing RGB_PIXELSIZE. Note that changing + * the offsets will also change the order in which colormap data is organized. + * RESTRICTIONS: + * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats. + * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not + * useful if you are using JPEG color spaces other than YCbCr or grayscale. + * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE + * is not 3 (they don't understand about dummy color components!). So you + * can't use color quantization if you change that value. + */ + +#define RGB_RED 0 /* Offset of Red in an RGB scanline element */ +#define RGB_GREEN 1 /* Offset of Green */ +#define RGB_BLUE 2 /* Offset of Blue */ +#define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */ + + +/* Definitions for speed-related optimizations. */ + + +/* If your compiler supports inline functions, define INLINE + * as the inline keyword; otherwise define it as empty. + */ + +#ifndef INLINE +#ifdef __GNUC__ /* for instance, GNU C knows about inline */ +#define INLINE __inline__ +#endif +#ifndef INLINE +#define INLINE /* default is to define it as empty */ +#endif +#endif + + +/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying + * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER + * as short on such a machine. MULTIPLIER must be at least 16 bits wide. + */ + +#ifndef MULTIPLIER +#define MULTIPLIER int /* type for fastest integer multiply */ +#endif + + +/* FAST_FLOAT should be either float or double, whichever is done faster + * by your compiler. (Note that this type is only used in the floating point + * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.) + * Typically, float is faster in ANSI C compilers, while double is faster in + * pre-ANSI compilers (because they insist on converting to double anyway). + * The code below therefore chooses float if we have ANSI-style prototypes. + */ + +#ifndef FAST_FLOAT +#ifdef HAVE_PROTOTYPES +#define FAST_FLOAT float +#else +#define FAST_FLOAT double +#endif +#endif + +#endif /* JPEG_INTERNAL_OPTIONS */ |