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 * libjpeg-turbo Modifications: 8 * Copyright (C) 2009, 2011, 2014-2015, D. R. Commander. 9 * For conditions of distribution and use, see the accompanying README file. 10 * 11 * This file contains additional configuration options that customize the 12 * JPEG software for special applications or support machine-dependent 13 * optimizations. Most users will not need to touch this file. 14 */ 15 16 17 /* 18 * Maximum number of components (color channels) allowed in JPEG image. 19 * To meet the letter of the JPEG spec, set this to 255. However, darn 20 * few applications need more than 4 channels (maybe 5 for CMYK + alpha 21 * mask). We recommend 10 as a reasonable compromise; use 4 if you are 22 * really short on memory. (Each allowed component costs a hundred or so 23 * bytes of storage, whether actually used in an image or not.) 24 */ 25 26 #define MAX_COMPONENTS 10 /* maximum number of image components */ 27 28 29 /* 30 * Basic data types. 31 * You may need to change these if you have a machine with unusual data 32 * type sizes; for example, "char" not 8 bits, "short" not 16 bits, 33 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits, 34 * but it had better be at least 16. 35 */ 36 37 /* Representation of a single sample (pixel element value). 38 * We frequently allocate large arrays of these, so it's important to keep 39 * them small. But if you have memory to burn and access to char or short 40 * arrays is very slow on your hardware, you might want to change these. 41 */ 42 43 #if BITS_IN_JSAMPLE == 8 44 /* JSAMPLE should be the smallest type that will hold the values 0..255. 45 * You can use a signed char by having GETJSAMPLE mask it with 0xFF. 46 */ 47 48 #ifdef HAVE_UNSIGNED_CHAR 49 50 typedef unsigned char JSAMPLE; 51 #define GETJSAMPLE(value) ((int) (value)) 52 53 #else /* not HAVE_UNSIGNED_CHAR */ 54 55 typedef char JSAMPLE; 56 #ifdef __CHAR_UNSIGNED__ 57 #define GETJSAMPLE(value) ((int) (value)) 58 #else 59 #define GETJSAMPLE(value) ((int) (value) & 0xFF) 60 #endif /* __CHAR_UNSIGNED__ */ 61 62 #endif /* HAVE_UNSIGNED_CHAR */ 63 64 #define MAXJSAMPLE 255 65 #define CENTERJSAMPLE 128 66 67 #endif /* BITS_IN_JSAMPLE == 8 */ 68 69 70 #if BITS_IN_JSAMPLE == 12 71 /* JSAMPLE should be the smallest type that will hold the values 0..4095. 72 * On nearly all machines "short" will do nicely. 73 */ 74 75 typedef short JSAMPLE; 76 #define GETJSAMPLE(value) ((int) (value)) 77 78 #define MAXJSAMPLE 4095 79 #define CENTERJSAMPLE 2048 80 81 #endif /* BITS_IN_JSAMPLE == 12 */ 82 83 84 /* Representation of a DCT frequency coefficient. 85 * This should be a signed value of at least 16 bits; "short" is usually OK. 86 * Again, we allocate large arrays of these, but you can change to int 87 * if you have memory to burn and "short" is really slow. 88 */ 89 90 typedef short JCOEF; 91 92 93 /* Compressed datastreams are represented as arrays of JOCTET. 94 * These must be EXACTLY 8 bits wide, at least once they are written to 95 * external storage. Note that when using the stdio data source/destination 96 * managers, this is also the data type passed to fread/fwrite. 97 */ 98 99 #ifdef HAVE_UNSIGNED_CHAR 100 101 typedef unsigned char JOCTET; 102 #define GETJOCTET(value) (value) 103 104 #else /* not HAVE_UNSIGNED_CHAR */ 105 106 typedef char JOCTET; 107 #ifdef __CHAR_UNSIGNED__ 108 #define GETJOCTET(value) (value) 109 #else 110 #define GETJOCTET(value) ((value) & 0xFF) 111 #endif /* __CHAR_UNSIGNED__ */ 112 113 #endif /* HAVE_UNSIGNED_CHAR */ 114 115 116 /* These typedefs are used for various table entries and so forth. 117 * They must be at least as wide as specified; but making them too big 118 * won't cost a huge amount of memory, so we don't provide special 119 * extraction code like we did for JSAMPLE. (In other words, these 120 * typedefs live at a different point on the speed/space tradeoff curve.) 121 */ 122 123 /* UINT8 must hold at least the values 0..255. */ 124 125 #ifdef HAVE_UNSIGNED_CHAR 126 typedef unsigned char UINT8; 127 #else /* not HAVE_UNSIGNED_CHAR */ 128 #ifdef __CHAR_UNSIGNED__ 129 typedef char UINT8; 130 #else /* not __CHAR_UNSIGNED__ */ 131 typedef short UINT8; 132 #endif /* __CHAR_UNSIGNED__ */ 133 #endif /* HAVE_UNSIGNED_CHAR */ 134 135 /* UINT16 must hold at least the values 0..65535. */ 136 137 #ifdef HAVE_UNSIGNED_SHORT 138 typedef unsigned short UINT16; 139 #else /* not HAVE_UNSIGNED_SHORT */ 140 typedef unsigned int UINT16; 141 #endif /* HAVE_UNSIGNED_SHORT */ 142 143 /* INT16 must hold at least the values -32768..32767. */ 144 145 #ifndef XMD_H /* X11/xmd.h correctly defines INT16 */ 146 typedef short INT16; 147 #endif 148 149 /* INT32 must hold at least signed 32-bit values. */ 150 151 #ifndef XMD_H /* X11/xmd.h correctly defines INT32 */ 152 #ifndef _BASETSD_H_ /* Microsoft defines it in basetsd.h */ 153 #ifndef _BASETSD_H /* MinGW is slightly different */ 154 #ifndef QGLOBAL_H /* Qt defines it in qglobal.h */ 155 #define __INT32_IS_ACTUALLY_LONG 156 typedef long INT32; 157 #endif 158 #endif 159 #endif 160 #endif 161 162 /* Datatype used for image dimensions. The JPEG standard only supports 163 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore 164 * "unsigned int" is sufficient on all machines. However, if you need to 165 * handle larger images and you don't mind deviating from the spec, you 166 * can change this datatype. (Note that changing this datatype will 167 * potentially require modifying the SIMD code. The x86-64 SIMD extensions, 168 * in particular, assume a 32-bit JDIMENSION.) 169 */ 170 171 typedef unsigned int JDIMENSION; 172 173 #define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */ 174 175 176 /* These macros are used in all function definitions and extern declarations. 177 * You could modify them if you need to change function linkage conventions; 178 * in particular, you'll need to do that to make the library a Windows DLL. 179 * Another application is to make all functions global for use with debuggers 180 * or code profilers that require it. 181 */ 182 183 /* a function called through method pointers: */ 184 #define METHODDEF(type) static type 185 /* a function used only in its module: */ 186 #define LOCAL(type) static type 187 /* a function referenced thru EXTERNs: */ 188 #define GLOBAL(type) type 189 /* a reference to a GLOBAL function: */ 190 #define EXTERN(type) extern type 191 192 193 /* Originally, this macro was used as a way of defining function prototypes 194 * for both modern compilers as well as older compilers that did not support 195 * prototype parameters. libjpeg-turbo has never supported these older, 196 * non-ANSI compilers, but the macro is still included because there is some 197 * software out there that uses it. 198 */ 199 200 #define JMETHOD(type,methodname,arglist) type (*methodname) arglist 201 202 203 /* libjpeg-turbo no longer supports platforms that have far symbols (MS-DOS), 204 * but again, some software relies on this macro. 205 */ 206 207 #undef FAR 208 #define FAR 209 210 211 /* 212 * On a few systems, type boolean and/or its values FALSE, TRUE may appear 213 * in standard header files. Or you may have conflicts with application- 214 * specific header files that you want to include together with these files. 215 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work. 216 */ 217 218 #ifndef HAVE_BOOLEAN 219 typedef int boolean; 220 #endif 221 #ifndef FALSE /* in case these macros already exist */ 222 #define FALSE 0 /* values of boolean */ 223 #endif 224 #ifndef TRUE 225 #define TRUE 1 226 #endif 227 228 229 /* 230 * The remaining options affect code selection within the JPEG library, 231 * but they don't need to be visible to most applications using the library. 232 * To minimize application namespace pollution, the symbols won't be 233 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined. 234 */ 235 236 #ifdef JPEG_INTERNALS 237 #define JPEG_INTERNAL_OPTIONS 238 #endif 239 240 #ifdef JPEG_INTERNAL_OPTIONS 241 242 243 /* 244 * These defines indicate whether to include various optional functions. 245 * Undefining some of these symbols will produce a smaller but less capable 246 * library. Note that you can leave certain source files out of the 247 * compilation/linking process if you've #undef'd the corresponding symbols. 248 * (You may HAVE to do that if your compiler doesn't like null source files.) 249 */ 250 251 /* Capability options common to encoder and decoder: */ 252 253 #define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */ 254 #define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */ 255 #define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */ 256 257 /* Encoder capability options: */ 258 259 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ 260 #define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ 261 #define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */ 262 /* Note: if you selected 12-bit data precision, it is dangerous to turn off 263 * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit 264 * precision, so jchuff.c normally uses entropy optimization to compute 265 * usable tables for higher precision. If you don't want to do optimization, 266 * you'll have to supply different default Huffman tables. 267 * The exact same statements apply for progressive JPEG: the default tables 268 * don't work for progressive mode. (This may get fixed, however.) 269 */ 270 #define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */ 271 272 /* Decoder capability options: */ 273 274 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ 275 #define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ 276 #define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */ 277 #define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */ 278 #define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */ 279 #undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */ 280 #define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */ 281 #define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */ 282 #define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */ 283 284 /* more capability options later, no doubt */ 285 286 287 /* 288 * The RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros are a vestigial 289 * feature of libjpeg. The idea was that, if an application developer needed 290 * to compress from/decompress to a BGR/BGRX/RGBX/XBGR/XRGB buffer, they could 291 * change these macros, rebuild libjpeg, and link their application statically 292 * with it. In reality, few people ever did this, because there were some 293 * severe restrictions involved (cjpeg and djpeg no longer worked properly, 294 * compressing/decompressing RGB JPEGs no longer worked properly, and the color 295 * quantizer wouldn't work with pixel sizes other than 3.) Further, since all 296 * of the O/S-supplied versions of libjpeg were built with the default values 297 * of RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE, many applications have 298 * come to regard these values as immutable. 299 * 300 * The libjpeg-turbo colorspace extensions provide a much cleaner way of 301 * compressing from/decompressing to buffers with arbitrary component orders 302 * and pixel sizes. Thus, we do not support changing the values of RGB_RED, 303 * RGB_GREEN, RGB_BLUE, or RGB_PIXELSIZE. In addition to the restrictions 304 * listed above, changing these values will also break the SIMD extensions and 305 * the regression tests. 306 */ 307 308 #define RGB_RED 0 /* Offset of Red in an RGB scanline element */ 309 #define RGB_GREEN 1 /* Offset of Green */ 310 #define RGB_BLUE 2 /* Offset of Blue */ 311 #define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */ 312 313 #define JPEG_NUMCS 17 314 315 #define EXT_RGB_RED 0 316 #define EXT_RGB_GREEN 1 317 #define EXT_RGB_BLUE 2 318 #define EXT_RGB_PIXELSIZE 3 319 320 #define EXT_RGBX_RED 0 321 #define EXT_RGBX_GREEN 1 322 #define EXT_RGBX_BLUE 2 323 #define EXT_RGBX_PIXELSIZE 4 324 325 #define EXT_BGR_RED 2 326 #define EXT_BGR_GREEN 1 327 #define EXT_BGR_BLUE 0 328 #define EXT_BGR_PIXELSIZE 3 329 330 #define EXT_BGRX_RED 2 331 #define EXT_BGRX_GREEN 1 332 #define EXT_BGRX_BLUE 0 333 #define EXT_BGRX_PIXELSIZE 4 334 335 #define EXT_XBGR_RED 3 336 #define EXT_XBGR_GREEN 2 337 #define EXT_XBGR_BLUE 1 338 #define EXT_XBGR_PIXELSIZE 4 339 340 #define EXT_XRGB_RED 1 341 #define EXT_XRGB_GREEN 2 342 #define EXT_XRGB_BLUE 3 343 #define EXT_XRGB_PIXELSIZE 4 344 345 static const int rgb_red[JPEG_NUMCS] = { 346 -1, -1, RGB_RED, -1, -1, -1, EXT_RGB_RED, EXT_RGBX_RED, 347 EXT_BGR_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED, 348 EXT_RGBX_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED, 349 -1 350 }; 351 352 static const int rgb_green[JPEG_NUMCS] = { 353 -1, -1, RGB_GREEN, -1, -1, -1, EXT_RGB_GREEN, EXT_RGBX_GREEN, 354 EXT_BGR_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN, 355 EXT_RGBX_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN, 356 -1 357 }; 358 359 static const int rgb_blue[JPEG_NUMCS] = { 360 -1, -1, RGB_BLUE, -1, -1, -1, EXT_RGB_BLUE, EXT_RGBX_BLUE, 361 EXT_BGR_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE, 362 EXT_RGBX_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE, 363 -1 364 }; 365 366 static const int rgb_pixelsize[JPEG_NUMCS] = { 367 -1, -1, RGB_PIXELSIZE, -1, -1, -1, EXT_RGB_PIXELSIZE, EXT_RGBX_PIXELSIZE, 368 EXT_BGR_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE, 369 EXT_RGBX_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE, 370 -1 371 }; 372 373 /* Definitions for speed-related optimizations. */ 374 375 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying 376 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER 377 * as short on such a machine. MULTIPLIER must be at least 16 bits wide. 378 */ 379 380 #ifndef MULTIPLIER 381 #ifndef WITH_SIMD 382 #define MULTIPLIER int /* type for fastest integer multiply */ 383 #else 384 #define MULTIPLIER short /* prefer 16-bit with SIMD for parellelism */ 385 #endif 386 #endif 387 388 389 /* FAST_FLOAT should be either float or double, whichever is done faster 390 * by your compiler. (Note that this type is only used in the floating point 391 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.) 392 */ 393 394 #ifndef FAST_FLOAT 395 #define FAST_FLOAT float 396 #endif 397 398 #endif /* JPEG_INTERNAL_OPTIONS */ 399
