jmorecfg.h (14017B)
1 /* 2 * jmorecfg.h 3 * 4 * This file was part of the Independent JPEG Group's software: 5 * Copyright (C) 1991-1997, Thomas G. Lane. 6 * Modified 1997-2009 by Guido Vollbeding. 7 * Lossless JPEG Modifications: 8 * Copyright (C) 1999, Ken Murchison. 9 * libjpeg-turbo Modifications: 10 * Copyright (C) 2009, 2011, 2014-2015, 2018, 2020, 2022, D. R. Commander. 11 * For conditions of distribution and use, see the accompanying README.ijg 12 * file. 13 * 14 * This file contains additional configuration options that customize the 15 * JPEG software for special applications or support machine-dependent 16 * optimizations. Most users will not need to touch this file. 17 */ 18 19 #include <stdint.h> 20 21 /* 22 * Maximum number of components (color channels) allowed in JPEG image. 23 * To meet the letter of Rec. ITU-T T.81 | ISO/IEC 10918-1, set this to 255. 24 * However, darn few applications need more than 4 channels (maybe 5 for CMYK + 25 * alpha mask). We recommend 10 as a reasonable compromise; use 4 if you are 26 * really short on memory. (Each allowed component costs a hundred or so 27 * bytes of storage, whether actually used in an image or not.) 28 */ 29 30 #define MAX_COMPONENTS 10 /* maximum number of image components */ 31 32 33 /* 34 * Basic data types. 35 * You may need to change these if you have a machine with unusual data 36 * type sizes; for example, "char" not 8 bits, "short" not 16 bits, 37 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits, 38 * but it had better be at least 16. 39 */ 40 41 /* Representation of a single sample (pixel element value). 42 * We frequently allocate large arrays of these, so it's important to keep 43 * them small. But if you have memory to burn and access to char or short 44 * arrays is very slow on your hardware, you might want to change these. 45 */ 46 47 /* JSAMPLE should be the smallest type that will hold the values 0..255. */ 48 49 typedef unsigned char JSAMPLE; 50 #define GETJSAMPLE(value) ((int)(value)) 51 52 #define MAXJSAMPLE 255 53 #define CENTERJSAMPLE 128 54 55 56 /* J12SAMPLE should be the smallest type that will hold the values 0..4095. */ 57 58 typedef short J12SAMPLE; 59 60 #define MAXJ12SAMPLE 4095 61 #define CENTERJ12SAMPLE 2048 62 63 64 /* J16SAMPLE should be the smallest type that will hold the values 0..65535. */ 65 66 typedef unsigned short J16SAMPLE; 67 68 #define MAXJ16SAMPLE 65535 69 #define CENTERJ16SAMPLE 32768 70 71 72 /* Representation of a DCT frequency coefficient. 73 * This should be a signed value of at least 16 bits; "short" is usually OK. 74 * Again, we allocate large arrays of these, but you can change to int 75 * if you have memory to burn and "short" is really slow. 76 */ 77 78 typedef short JCOEF; 79 80 81 /* Compressed datastreams are represented as arrays of JOCTET. 82 * These must be EXACTLY 8 bits wide, at least once they are written to 83 * external storage. Note that when using the stdio data source/destination 84 * managers, this is also the data type passed to fread/fwrite. 85 */ 86 87 typedef unsigned char JOCTET; 88 #define GETJOCTET(value) (value) 89 90 91 /* These typedefs are used for various table entries and so forth. 92 * They must be at least as wide as specified; but making them too big 93 * won't cost a huge amount of memory, so we don't provide special 94 * extraction code like we did for JSAMPLE. (In other words, these 95 * typedefs live at a different point on the speed/space tradeoff curve.) 96 */ 97 98 /* UINT8 must hold at least the values 0..255. */ 99 100 typedef uint8_t UINT8; 101 102 /* UINT16 must hold at least the values 0..65535. */ 103 104 typedef uint16_t UINT16; 105 106 /* INT16 must hold at least the values -32768..32767. */ 107 108 typedef int16_t INT16; 109 110 /* INT32 must hold at least signed 32-bit values. 111 * 112 * NOTE: The INT32 typedef dates back to libjpeg v5 (1994.) Integers were 113 * sometimes 16-bit back then (MS-DOS), which is why INT32 is typedef'd to 114 * long. It also wasn't common (or at least as common) in 1994 for INT32 to be 115 * defined by platform headers. Since then, however, INT32 is defined in 116 * several other common places: 117 * 118 * Xmd.h (X11 header) typedefs INT32 to int on 64-bit platforms and long on 119 * 32-bit platforms (i.e always a 32-bit signed type.) 120 * 121 * basetsd.h (Win32 header) typedefs INT32 to int (always a 32-bit signed type 122 * on modern platforms.) 123 * 124 * qglobal.h (Qt header) typedefs INT32 to int (always a 32-bit signed type on 125 * modern platforms.) 126 * 127 * This is a recipe for conflict, since "long" and "int" aren't always 128 * compatible types. Since the definition of INT32 has technically been part 129 * of the libjpeg API for more than 20 years, we can't remove it, but we do not 130 * use it internally any longer. We instead define a separate type (JLONG) 131 * for internal use, which ensures that internal behavior will always be the 132 * same regardless of any external headers that may be included. 133 */ 134 135 typedef int32_t INT32; 136 137 /* Datatype used for image dimensions. The JPEG standard only supports 138 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore 139 * "unsigned int" is sufficient on all machines. However, if you need to 140 * handle larger images and you don't mind deviating from the spec, you 141 * can change this datatype. (Note that changing this datatype will 142 * potentially require modifying the SIMD code. The x86-64 SIMD extensions, 143 * in particular, assume a 32-bit JDIMENSION.) 144 */ 145 146 typedef unsigned int JDIMENSION; 147 148 #define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */ 149 150 151 /* These macros are used in all function definitions and extern declarations. 152 * You could modify them if you need to change function linkage conventions; 153 * in particular, you'll need to do that to make the library a Windows DLL. 154 * Another application is to make all functions global for use with debuggers 155 * or code profilers that require it. 156 */ 157 158 /* a function called through method pointers: */ 159 #define METHODDEF(type) static type 160 /* a function used only in its module: */ 161 #define LOCAL(type) static type 162 /* a function referenced thru EXTERNs: */ 163 #define GLOBAL(type) type 164 /* a reference to a GLOBAL function: */ 165 #define EXTERN(type) extern type 166 167 168 /* Originally, this macro was used as a way of defining function prototypes 169 * for both modern compilers as well as older compilers that did not support 170 * prototype parameters. libjpeg-turbo has never supported these older, 171 * non-ANSI compilers, but the macro is still included because there is some 172 * software out there that uses it. 173 */ 174 175 #define JMETHOD(type, methodname, arglist) type (*methodname) arglist 176 177 178 /* libjpeg-turbo no longer supports platforms that have far symbols (MS-DOS), 179 * but again, some software relies on this macro. 180 */ 181 182 #undef FAR 183 #define FAR 184 185 186 /* 187 * On a few systems, type boolean and/or its values FALSE, TRUE may appear 188 * in standard header files. Or you may have conflicts with application- 189 * specific header files that you want to include together with these files. 190 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work. 191 */ 192 193 #ifndef HAVE_BOOLEAN 194 typedef int boolean; 195 #endif 196 #ifndef FALSE /* in case these macros already exist */ 197 #define FALSE 0 /* values of boolean */ 198 #endif 199 #ifndef TRUE 200 #define TRUE 1 201 #endif 202 203 204 /* 205 * The remaining options affect code selection within the JPEG library, 206 * but they don't need to be visible to most applications using the library. 207 * To minimize application namespace pollution, the symbols won't be 208 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined. 209 */ 210 211 #ifdef JPEG_INTERNALS 212 #define JPEG_INTERNAL_OPTIONS 213 #endif 214 215 #ifdef JPEG_INTERNAL_OPTIONS 216 217 218 /* 219 * These defines indicate whether to include various optional functions. 220 * Undefining some of these symbols will produce a smaller but less capable 221 * library. Note that you can leave certain source files out of the 222 * compilation/linking process if you've #undef'd the corresponding symbols. 223 * (You may HAVE to do that if your compiler doesn't like null source files.) 224 */ 225 226 /* Capability options common to encoder and decoder: */ 227 228 #define DCT_ISLOW_SUPPORTED /* accurate integer method */ 229 #define DCT_IFAST_SUPPORTED /* less accurate int method [legacy feature] */ 230 #define DCT_FLOAT_SUPPORTED /* floating-point method [legacy feature] */ 231 232 /* Encoder capability options: */ 233 234 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ 235 #define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ 236 #define C_LOSSLESS_SUPPORTED /* Lossless JPEG? */ 237 #define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */ 238 /* Note: if you selected 12-bit data precision, it is dangerous to turn off 239 * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit 240 * precision, so jchuff.c normally uses entropy optimization to compute 241 * usable tables for higher precision. If you don't want to do optimization, 242 * you'll have to supply different default Huffman tables. 243 * The exact same statements apply for progressive and lossless JPEG: 244 * the default tables don't work for progressive mode or lossless mode. 245 * (This may get fixed, however.) 246 */ 247 #define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */ 248 249 /* Decoder capability options: */ 250 251 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ 252 #define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ 253 #define D_LOSSLESS_SUPPORTED /* Lossless JPEG? */ 254 #define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */ 255 #define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */ 256 #define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */ 257 #undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */ 258 #define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */ 259 #define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */ 260 #define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */ 261 262 /* more capability options later, no doubt */ 263 264 265 /* 266 * The RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros are a vestigial 267 * feature of libjpeg. The idea was that, if an application developer needed 268 * to compress from/decompress to a BGR/BGRX/RGBX/XBGR/XRGB buffer, they could 269 * change these macros, rebuild libjpeg, and link their application statically 270 * with it. In reality, few people ever did this, because there were some 271 * severe restrictions involved (cjpeg and djpeg no longer worked properly, 272 * compressing/decompressing RGB JPEGs no longer worked properly, and the color 273 * quantizer wouldn't work with pixel sizes other than 3.) Furthermore, since 274 * all of the O/S-supplied versions of libjpeg were built with the default 275 * values of RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE, many applications 276 * have come to regard these values as immutable. 277 * 278 * The libjpeg-turbo colorspace extensions provide a much cleaner way of 279 * compressing from/decompressing to buffers with arbitrary component orders 280 * and pixel sizes. Thus, we do not support changing the values of RGB_RED, 281 * RGB_GREEN, RGB_BLUE, or RGB_PIXELSIZE. In addition to the restrictions 282 * listed above, changing these values will also break the SIMD extensions and 283 * the regression tests. 284 */ 285 286 #define RGB_RED 0 /* Offset of Red in an RGB scanline element */ 287 #define RGB_GREEN 1 /* Offset of Green */ 288 #define RGB_BLUE 2 /* Offset of Blue */ 289 #define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */ 290 291 #define JPEG_NUMCS 17 292 293 #define EXT_RGB_RED 0 294 #define EXT_RGB_GREEN 1 295 #define EXT_RGB_BLUE 2 296 #define EXT_RGB_PIXELSIZE 3 297 298 #define EXT_RGBX_RED 0 299 #define EXT_RGBX_GREEN 1 300 #define EXT_RGBX_BLUE 2 301 #define EXT_RGBX_PIXELSIZE 4 302 303 #define EXT_BGR_RED 2 304 #define EXT_BGR_GREEN 1 305 #define EXT_BGR_BLUE 0 306 #define EXT_BGR_PIXELSIZE 3 307 308 #define EXT_BGRX_RED 2 309 #define EXT_BGRX_GREEN 1 310 #define EXT_BGRX_BLUE 0 311 #define EXT_BGRX_PIXELSIZE 4 312 313 #define EXT_XBGR_RED 3 314 #define EXT_XBGR_GREEN 2 315 #define EXT_XBGR_BLUE 1 316 #define EXT_XBGR_PIXELSIZE 4 317 318 #define EXT_XRGB_RED 1 319 #define EXT_XRGB_GREEN 2 320 #define EXT_XRGB_BLUE 3 321 #define EXT_XRGB_PIXELSIZE 4 322 323 static const int rgb_red[JPEG_NUMCS] = { 324 -1, -1, RGB_RED, -1, -1, -1, EXT_RGB_RED, EXT_RGBX_RED, 325 EXT_BGR_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED, 326 EXT_RGBX_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED, 327 -1 328 }; 329 330 static const int rgb_green[JPEG_NUMCS] = { 331 -1, -1, RGB_GREEN, -1, -1, -1, EXT_RGB_GREEN, EXT_RGBX_GREEN, 332 EXT_BGR_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN, 333 EXT_RGBX_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN, 334 -1 335 }; 336 337 static const int rgb_blue[JPEG_NUMCS] = { 338 -1, -1, RGB_BLUE, -1, -1, -1, EXT_RGB_BLUE, EXT_RGBX_BLUE, 339 EXT_BGR_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE, 340 EXT_RGBX_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE, 341 -1 342 }; 343 344 static const int rgb_pixelsize[JPEG_NUMCS] = { 345 -1, -1, RGB_PIXELSIZE, -1, -1, -1, EXT_RGB_PIXELSIZE, EXT_RGBX_PIXELSIZE, 346 EXT_BGR_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE, 347 EXT_RGBX_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE, 348 -1 349 }; 350 351 /* Definitions for speed-related optimizations. */ 352 353 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying 354 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER 355 * as short on such a machine. MULTIPLIER must be at least 16 bits wide. 356 */ 357 358 #ifndef MULTIPLIER 359 #ifndef WITH_SIMD 360 #define MULTIPLIER int /* type for fastest integer multiply */ 361 #else 362 #define MULTIPLIER short /* prefer 16-bit with SIMD for parellelism */ 363 #endif 364 #endif 365 366 367 /* FAST_FLOAT should be either float or double, whichever is done faster 368 * by your compiler. (Note that this type is only used in the floating point 369 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.) 370 */ 371 372 #ifndef FAST_FLOAT 373 #define FAST_FLOAT float 374 #endif 375 376 #endif /* JPEG_INTERNAL_OPTIONS */