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, 2018, D. R. Commander. 9 * For conditions of distribution and use, see the accompanying README.ijg 10 * file. 11 * 12 * This file contains additional configuration options that customize the 13 * JPEG software for special applications or support machine-dependent 14 * optimizations. Most users will not need to touch this file. 15 */ 16 17 18 /* 19 * Maximum number of components (color channels) allowed in JPEG image. 20 * To meet the letter of Rec. ITU-T T.81 | ISO/IEC 10918-1, set this to 255. 21 * However, darn few applications need more than 4 channels (maybe 5 for CMYK + 22 * alpha mask). We recommend 10 as a reasonable compromise; use 4 if you are 23 * really short on memory. (Each allowed component costs a hundred or so 24 * bytes of storage, whether actually used in an image or not.) 25 */ 26 27 #define MAX_COMPONENTS 10 /* maximum number of image components */ 28 29 30 /* 31 * Basic data types. 32 * You may need to change these if you have a machine with unusual data 33 * type sizes; for example, "char" not 8 bits, "short" not 16 bits, 34 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits, 35 * but it had better be at least 16. 36 */ 37 38 /* Representation of a single sample (pixel element value). 39 * We frequently allocate large arrays of these, so it's important to keep 40 * them small. But if you have memory to burn and access to char or short 41 * arrays is very slow on your hardware, you might want to change these. 42 */ 43 44 #if BITS_IN_JSAMPLE == 8 45 /* JSAMPLE should be the smallest type that will hold the values 0..255. 46 * You can use a signed char by having GETJSAMPLE mask it with 0xFF. 47 */ 48 49 #ifdef HAVE_UNSIGNED_CHAR 50 51 typedef unsigned char JSAMPLE; 52 #define GETJSAMPLE(value) ((int)(value)) 53 54 #else /* not HAVE_UNSIGNED_CHAR */ 55 56 typedef char JSAMPLE; 57 #ifdef __CHAR_UNSIGNED__ 58 #define GETJSAMPLE(value) ((int)(value)) 59 #else 60 #define GETJSAMPLE(value) ((int)(value) & 0xFF) 61 #endif /* __CHAR_UNSIGNED__ */ 62 63 #endif /* HAVE_UNSIGNED_CHAR */ 64 65 #define MAXJSAMPLE 255 66 #define CENTERJSAMPLE 128 67 68 #endif /* BITS_IN_JSAMPLE == 8 */ 69 70 71 #if BITS_IN_JSAMPLE == 12 72 /* JSAMPLE should be the smallest type that will hold the values 0..4095. 73 * On nearly all machines "short" will do nicely. 74 */ 75 76 typedef short JSAMPLE; 77 #define GETJSAMPLE(value) ((int)(value)) 78 79 #define MAXJSAMPLE 4095 80 #define CENTERJSAMPLE 2048 81 82 #endif /* BITS_IN_JSAMPLE == 12 */ 83 84 85 /* Representation of a DCT frequency coefficient. 86 * This should be a signed value of at least 16 bits; "short" is usually OK. 87 * Again, we allocate large arrays of these, but you can change to int 88 * if you have memory to burn and "short" is really slow. 89 */ 90 91 typedef short JCOEF; 92 93 94 /* Compressed datastreams are represented as arrays of JOCTET. 95 * These must be EXACTLY 8 bits wide, at least once they are written to 96 * external storage. Note that when using the stdio data source/destination 97 * managers, this is also the data type passed to fread/fwrite. 98 */ 99 100 #ifdef HAVE_UNSIGNED_CHAR 101 102 typedef unsigned char JOCTET; 103 #define GETJOCTET(value) (value) 104 105 #else /* not HAVE_UNSIGNED_CHAR */ 106 107 typedef char JOCTET; 108 #ifdef __CHAR_UNSIGNED__ 109 #define GETJOCTET(value) (value) 110 #else 111 #define GETJOCTET(value) ((value) & 0xFF) 112 #endif /* __CHAR_UNSIGNED__ */ 113 114 #endif /* HAVE_UNSIGNED_CHAR */ 115 116 117 /* These typedefs are used for various table entries and so forth. 118 * They must be at least as wide as specified; but making them too big 119 * won't cost a huge amount of memory, so we don't provide special 120 * extraction code like we did for JSAMPLE. (In other words, these 121 * typedefs live at a different point on the speed/space tradeoff curve.) 122 */ 123 124 /* UINT8 must hold at least the values 0..255. */ 125 126 #ifdef HAVE_UNSIGNED_CHAR 127 typedef unsigned char UINT8; 128 #else /* not HAVE_UNSIGNED_CHAR */ 129 #ifdef __CHAR_UNSIGNED__ 130 typedef char UINT8; 131 #else /* not __CHAR_UNSIGNED__ */ 132 typedef short UINT8; 133 #endif /* __CHAR_UNSIGNED__ */ 134 #endif /* HAVE_UNSIGNED_CHAR */ 135 136 /* UINT16 must hold at least the values 0..65535. */ 137 138 #ifdef HAVE_UNSIGNED_SHORT 139 typedef unsigned short UINT16; 140 #else /* not HAVE_UNSIGNED_SHORT */ 141 typedef unsigned int UINT16; 142 #endif /* HAVE_UNSIGNED_SHORT */ 143 144 /* INT16 must hold at least the values -32768..32767. */ 145 146 #ifndef XMD_H /* X11/xmd.h correctly defines INT16 */ 147 typedef short INT16; 148 #endif 149 150 /* INT32 must hold at least signed 32-bit values. 151 * 152 * NOTE: The INT32 typedef dates back to libjpeg v5 (1994.) Integers were 153 * sometimes 16-bit back then (MS-DOS), which is why INT32 is typedef'd to 154 * long. It also wasn't common (or at least as common) in 1994 for INT32 to be 155 * defined by platform headers. Since then, however, INT32 is defined in 156 * several other common places: 157 * 158 * Xmd.h (X11 header) typedefs INT32 to int on 64-bit platforms and long on 159 * 32-bit platforms (i.e always a 32-bit signed type.) 160 * 161 * basetsd.h (Win32 header) typedefs INT32 to int (always a 32-bit signed type 162 * on modern platforms.) 163 * 164 * qglobal.h (Qt header) typedefs INT32 to int (always a 32-bit signed type on 165 * modern platforms.) 166 * 167 * This is a recipe for conflict, since "long" and "int" aren't always 168 * compatible types. Since the definition of INT32 has technically been part 169 * of the libjpeg API for more than 20 years, we can't remove it, but we do not 170 * use it internally any longer. We instead define a separate type (JLONG) 171 * for internal use, which ensures that internal behavior will always be the 172 * same regardless of any external headers that may be included. 173 */ 174 175 #ifndef XMD_H /* X11/xmd.h correctly defines INT32 */ 176 #ifndef _BASETSD_H_ /* Microsoft defines it in basetsd.h */ 177 #ifndef _BASETSD_H /* MinGW is slightly different */ 178 #ifndef QGLOBAL_H /* Qt defines it in qglobal.h */ 179 typedef long INT32; 180 #endif 181 #endif 182 #endif 183 #endif 184 185 /* Datatype used for image dimensions. The JPEG standard only supports 186 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore 187 * "unsigned int" is sufficient on all machines. However, if you need to 188 * handle larger images and you don't mind deviating from the spec, you 189 * can change this datatype. (Note that changing this datatype will 190 * potentially require modifying the SIMD code. The x86-64 SIMD extensions, 191 * in particular, assume a 32-bit JDIMENSION.) 192 */ 193 194 typedef unsigned int JDIMENSION; 195 196 #define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */ 197 198 199 /* These macros are used in all function definitions and extern declarations. 200 * You could modify them if you need to change function linkage conventions; 201 * in particular, you'll need to do that to make the library a Windows DLL. 202 * Another application is to make all functions global for use with debuggers 203 * or code profilers that require it. 204 */ 205 206 /* a function called through method pointers: */ 207 #define METHODDEF(type) static type 208 /* a function used only in its module: */ 209 #define LOCAL(type) static type 210 /* a function referenced thru EXTERNs: */ 211 #define GLOBAL(type) type 212 /* a reference to a GLOBAL function: */ 213 #define EXTERN(type) extern type 214 215 216 /* Originally, this macro was used as a way of defining function prototypes 217 * for both modern compilers as well as older compilers that did not support 218 * prototype parameters. libjpeg-turbo has never supported these older, 219 * non-ANSI compilers, but the macro is still included because there is some 220 * software out there that uses it. 221 */ 222 223 #define JMETHOD(type, methodname, arglist) type (*methodname) arglist 224 225 226 /* libjpeg-turbo no longer supports platforms that have far symbols (MS-DOS), 227 * but again, some software relies on this macro. 228 */ 229 230 #undef FAR 231 #define FAR 232 233 234 /* 235 * On a few systems, type boolean and/or its values FALSE, TRUE may appear 236 * in standard header files. Or you may have conflicts with application- 237 * specific header files that you want to include together with these files. 238 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work. 239 */ 240 241 #ifndef HAVE_BOOLEAN 242 typedef int boolean; 243 #endif 244 #ifndef FALSE /* in case these macros already exist */ 245 #define FALSE 0 /* values of boolean */ 246 #endif 247 #ifndef TRUE 248 #define TRUE 1 249 #endif 250 251 252 /* 253 * The remaining options affect code selection within the JPEG library, 254 * but they don't need to be visible to most applications using the library. 255 * To minimize application namespace pollution, the symbols won't be 256 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined. 257 */ 258 259 #ifdef JPEG_INTERNALS 260 #define JPEG_INTERNAL_OPTIONS 261 #endif 262 263 #ifdef JPEG_INTERNAL_OPTIONS 264 265 266 /* 267 * These defines indicate whether to include various optional functions. 268 * Undefining some of these symbols will produce a smaller but less capable 269 * library. Note that you can leave certain source files out of the 270 * compilation/linking process if you've #undef'd the corresponding symbols. 271 * (You may HAVE to do that if your compiler doesn't like null source files.) 272 */ 273 274 /* Capability options common to encoder and decoder: */ 275 276 #define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */ 277 #define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */ 278 #define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */ 279 280 /* Encoder capability options: */ 281 282 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ 283 #define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ 284 #define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */ 285 /* Note: if you selected 12-bit data precision, it is dangerous to turn off 286 * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit 287 * precision, so jchuff.c normally uses entropy optimization to compute 288 * usable tables for higher precision. If you don't want to do optimization, 289 * you'll have to supply different default Huffman tables. 290 * The exact same statements apply for progressive JPEG: the default tables 291 * don't work for progressive mode. (This may get fixed, however.) 292 */ 293 #define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */ 294 295 /* Decoder capability options: */ 296 297 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ 298 #define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ 299 #define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */ 300 #define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */ 301 #define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */ 302 #undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */ 303 #define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */ 304 #define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */ 305 #define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */ 306 307 /* more capability options later, no doubt */ 308 309 310 /* 311 * The RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros are a vestigial 312 * feature of libjpeg. The idea was that, if an application developer needed 313 * to compress from/decompress to a BGR/BGRX/RGBX/XBGR/XRGB buffer, they could 314 * change these macros, rebuild libjpeg, and link their application statically 315 * with it. In reality, few people ever did this, because there were some 316 * severe restrictions involved (cjpeg and djpeg no longer worked properly, 317 * compressing/decompressing RGB JPEGs no longer worked properly, and the color 318 * quantizer wouldn't work with pixel sizes other than 3.) Furthermore, since 319 * all of the O/S-supplied versions of libjpeg were built with the default 320 * values of RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE, many applications 321 * have come to regard these values as immutable. 322 * 323 * The libjpeg-turbo colorspace extensions provide a much cleaner way of 324 * compressing from/decompressing to buffers with arbitrary component orders 325 * and pixel sizes. Thus, we do not support changing the values of RGB_RED, 326 * RGB_GREEN, RGB_BLUE, or RGB_PIXELSIZE. In addition to the restrictions 327 * listed above, changing these values will also break the SIMD extensions and 328 * the regression tests. 329 */ 330 331 #define RGB_RED 0 /* Offset of Red in an RGB scanline element */ 332 #define RGB_GREEN 1 /* Offset of Green */ 333 #define RGB_BLUE 2 /* Offset of Blue */ 334 #define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */ 335 336 #define JPEG_NUMCS 17 337 338 #define EXT_RGB_RED 0 339 #define EXT_RGB_GREEN 1 340 #define EXT_RGB_BLUE 2 341 #define EXT_RGB_PIXELSIZE 3 342 343 #define EXT_RGBX_RED 0 344 #define EXT_RGBX_GREEN 1 345 #define EXT_RGBX_BLUE 2 346 #define EXT_RGBX_PIXELSIZE 4 347 348 #define EXT_BGR_RED 2 349 #define EXT_BGR_GREEN 1 350 #define EXT_BGR_BLUE 0 351 #define EXT_BGR_PIXELSIZE 3 352 353 #define EXT_BGRX_RED 2 354 #define EXT_BGRX_GREEN 1 355 #define EXT_BGRX_BLUE 0 356 #define EXT_BGRX_PIXELSIZE 4 357 358 #define EXT_XBGR_RED 3 359 #define EXT_XBGR_GREEN 2 360 #define EXT_XBGR_BLUE 1 361 #define EXT_XBGR_PIXELSIZE 4 362 363 #define EXT_XRGB_RED 1 364 #define EXT_XRGB_GREEN 2 365 #define EXT_XRGB_BLUE 3 366 #define EXT_XRGB_PIXELSIZE 4 367 368 static const int rgb_red[JPEG_NUMCS] = { 369 -1, -1, RGB_RED, -1, -1, -1, EXT_RGB_RED, EXT_RGBX_RED, 370 EXT_BGR_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED, 371 EXT_RGBX_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED, 372 -1 373 }; 374 375 static const int rgb_green[JPEG_NUMCS] = { 376 -1, -1, RGB_GREEN, -1, -1, -1, EXT_RGB_GREEN, EXT_RGBX_GREEN, 377 EXT_BGR_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN, 378 EXT_RGBX_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN, 379 -1 380 }; 381 382 static const int rgb_blue[JPEG_NUMCS] = { 383 -1, -1, RGB_BLUE, -1, -1, -1, EXT_RGB_BLUE, EXT_RGBX_BLUE, 384 EXT_BGR_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE, 385 EXT_RGBX_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE, 386 -1 387 }; 388 389 static const int rgb_pixelsize[JPEG_NUMCS] = { 390 -1, -1, RGB_PIXELSIZE, -1, -1, -1, EXT_RGB_PIXELSIZE, EXT_RGBX_PIXELSIZE, 391 EXT_BGR_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE, 392 EXT_RGBX_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE, 393 -1 394 }; 395 396 /* Definitions for speed-related optimizations. */ 397 398 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying 399 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER 400 * as short on such a machine. MULTIPLIER must be at least 16 bits wide. 401 */ 402 403 #ifndef MULTIPLIER 404 #ifndef WITH_SIMD 405 #define MULTIPLIER int /* type for fastest integer multiply */ 406 #else 407 #define MULTIPLIER short /* prefer 16-bit with SIMD for parellelism */ 408 #endif 409 #endif 410 411 412 /* FAST_FLOAT should be either float or double, whichever is done faster 413 * by your compiler. (Note that this type is only used in the floating point 414 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.) 415 */ 416 417 #ifndef FAST_FLOAT 418 #define FAST_FLOAT float 419 #endif 420 421 #endif /* JPEG_INTERNAL_OPTIONS */ 422
