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