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annotate CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/jmorecfg.h @ 69:33d812a61356

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planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 17:55:14 -0400
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jpayne@69 1 /*
jpayne@69 2 * jmorecfg.h
jpayne@69 3 *
jpayne@69 4 * Copyright (C) 1991-1997, Thomas G. Lane.
jpayne@69 5 * Modified 1997-2013 by Guido Vollbeding.
jpayne@69 6 * This file is part of the Independent JPEG Group's software.
jpayne@69 7 * For conditions of distribution and use, see the accompanying README file.
jpayne@69 8 *
jpayne@69 9 * This file contains additional configuration options that customize the
jpayne@69 10 * JPEG software for special applications or support machine-dependent
jpayne@69 11 * optimizations. Most users will not need to touch this file.
jpayne@69 12 */
jpayne@69 13
jpayne@69 14
jpayne@69 15 /*
jpayne@69 16 * Define BITS_IN_JSAMPLE as either
jpayne@69 17 * 8 for 8-bit sample values (the usual setting)
jpayne@69 18 * 9 for 9-bit sample values
jpayne@69 19 * 10 for 10-bit sample values
jpayne@69 20 * 11 for 11-bit sample values
jpayne@69 21 * 12 for 12-bit sample values
jpayne@69 22 * Only 8, 9, 10, 11, and 12 bits sample data precision are supported for
jpayne@69 23 * full-feature DCT processing. Further depths up to 16-bit may be added
jpayne@69 24 * later for the lossless modes of operation.
jpayne@69 25 * Run-time selection and conversion of data precision will be added later
jpayne@69 26 * and are currently not supported, sorry.
jpayne@69 27 * Exception: The transcoding part (jpegtran) supports all settings in a
jpayne@69 28 * single instance, since it operates on the level of DCT coefficients and
jpayne@69 29 * not sample values. The DCT coefficients are of the same type (16 bits)
jpayne@69 30 * in all cases (see below).
jpayne@69 31 */
jpayne@69 32
jpayne@69 33 #define BITS_IN_JSAMPLE 8 /* use 8, 9, 10, 11, or 12 */
jpayne@69 34
jpayne@69 35
jpayne@69 36 /*
jpayne@69 37 * Maximum number of components (color channels) allowed in JPEG image.
jpayne@69 38 * To meet the letter of the JPEG spec, set this to 255. However, darn
jpayne@69 39 * few applications need more than 4 channels (maybe 5 for CMYK + alpha
jpayne@69 40 * mask). We recommend 10 as a reasonable compromise; use 4 if you are
jpayne@69 41 * really short on memory. (Each allowed component costs a hundred or so
jpayne@69 42 * bytes of storage, whether actually used in an image or not.)
jpayne@69 43 */
jpayne@69 44
jpayne@69 45 #define MAX_COMPONENTS 10 /* maximum number of image components */
jpayne@69 46
jpayne@69 47
jpayne@69 48 /*
jpayne@69 49 * Basic data types.
jpayne@69 50 * You may need to change these if you have a machine with unusual data
jpayne@69 51 * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
jpayne@69 52 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits,
jpayne@69 53 * but it had better be at least 16.
jpayne@69 54 */
jpayne@69 55
jpayne@69 56 /* Representation of a single sample (pixel element value).
jpayne@69 57 * We frequently allocate large arrays of these, so it's important to keep
jpayne@69 58 * them small. But if you have memory to burn and access to char or short
jpayne@69 59 * arrays is very slow on your hardware, you might want to change these.
jpayne@69 60 */
jpayne@69 61
jpayne@69 62 #if BITS_IN_JSAMPLE == 8
jpayne@69 63 /* JSAMPLE should be the smallest type that will hold the values 0..255.
jpayne@69 64 * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
jpayne@69 65 */
jpayne@69 66
jpayne@69 67 #ifdef HAVE_UNSIGNED_CHAR
jpayne@69 68
jpayne@69 69 typedef unsigned char JSAMPLE;
jpayne@69 70 #define GETJSAMPLE(value) ((int) (value))
jpayne@69 71
jpayne@69 72 #else /* not HAVE_UNSIGNED_CHAR */
jpayne@69 73
jpayne@69 74 typedef char JSAMPLE;
jpayne@69 75 #ifdef CHAR_IS_UNSIGNED
jpayne@69 76 #define GETJSAMPLE(value) ((int) (value))
jpayne@69 77 #else
jpayne@69 78 #define GETJSAMPLE(value) ((int) (value) & 0xFF)
jpayne@69 79 #endif /* CHAR_IS_UNSIGNED */
jpayne@69 80
jpayne@69 81 #endif /* HAVE_UNSIGNED_CHAR */
jpayne@69 82
jpayne@69 83 #define MAXJSAMPLE 255
jpayne@69 84 #define CENTERJSAMPLE 128
jpayne@69 85
jpayne@69 86 #endif /* BITS_IN_JSAMPLE == 8 */
jpayne@69 87
jpayne@69 88
jpayne@69 89 #if BITS_IN_JSAMPLE == 9
jpayne@69 90 /* JSAMPLE should be the smallest type that will hold the values 0..511.
jpayne@69 91 * On nearly all machines "short" will do nicely.
jpayne@69 92 */
jpayne@69 93
jpayne@69 94 typedef short JSAMPLE;
jpayne@69 95 #define GETJSAMPLE(value) ((int) (value))
jpayne@69 96
jpayne@69 97 #define MAXJSAMPLE 511
jpayne@69 98 #define CENTERJSAMPLE 256
jpayne@69 99
jpayne@69 100 #endif /* BITS_IN_JSAMPLE == 9 */
jpayne@69 101
jpayne@69 102
jpayne@69 103 #if BITS_IN_JSAMPLE == 10
jpayne@69 104 /* JSAMPLE should be the smallest type that will hold the values 0..1023.
jpayne@69 105 * On nearly all machines "short" will do nicely.
jpayne@69 106 */
jpayne@69 107
jpayne@69 108 typedef short JSAMPLE;
jpayne@69 109 #define GETJSAMPLE(value) ((int) (value))
jpayne@69 110
jpayne@69 111 #define MAXJSAMPLE 1023
jpayne@69 112 #define CENTERJSAMPLE 512
jpayne@69 113
jpayne@69 114 #endif /* BITS_IN_JSAMPLE == 10 */
jpayne@69 115
jpayne@69 116
jpayne@69 117 #if BITS_IN_JSAMPLE == 11
jpayne@69 118 /* JSAMPLE should be the smallest type that will hold the values 0..2047.
jpayne@69 119 * On nearly all machines "short" will do nicely.
jpayne@69 120 */
jpayne@69 121
jpayne@69 122 typedef short JSAMPLE;
jpayne@69 123 #define GETJSAMPLE(value) ((int) (value))
jpayne@69 124
jpayne@69 125 #define MAXJSAMPLE 2047
jpayne@69 126 #define CENTERJSAMPLE 1024
jpayne@69 127
jpayne@69 128 #endif /* BITS_IN_JSAMPLE == 11 */
jpayne@69 129
jpayne@69 130
jpayne@69 131 #if BITS_IN_JSAMPLE == 12
jpayne@69 132 /* JSAMPLE should be the smallest type that will hold the values 0..4095.
jpayne@69 133 * On nearly all machines "short" will do nicely.
jpayne@69 134 */
jpayne@69 135
jpayne@69 136 typedef short JSAMPLE;
jpayne@69 137 #define GETJSAMPLE(value) ((int) (value))
jpayne@69 138
jpayne@69 139 #define MAXJSAMPLE 4095
jpayne@69 140 #define CENTERJSAMPLE 2048
jpayne@69 141
jpayne@69 142 #endif /* BITS_IN_JSAMPLE == 12 */
jpayne@69 143
jpayne@69 144
jpayne@69 145 /* Representation of a DCT frequency coefficient.
jpayne@69 146 * This should be a signed value of at least 16 bits; "short" is usually OK.
jpayne@69 147 * Again, we allocate large arrays of these, but you can change to int
jpayne@69 148 * if you have memory to burn and "short" is really slow.
jpayne@69 149 */
jpayne@69 150
jpayne@69 151 typedef short JCOEF;
jpayne@69 152
jpayne@69 153
jpayne@69 154 /* Compressed datastreams are represented as arrays of JOCTET.
jpayne@69 155 * These must be EXACTLY 8 bits wide, at least once they are written to
jpayne@69 156 * external storage. Note that when using the stdio data source/destination
jpayne@69 157 * managers, this is also the data type passed to fread/fwrite.
jpayne@69 158 */
jpayne@69 159
jpayne@69 160 #ifdef HAVE_UNSIGNED_CHAR
jpayne@69 161
jpayne@69 162 typedef unsigned char JOCTET;
jpayne@69 163 #define GETJOCTET(value) (value)
jpayne@69 164
jpayne@69 165 #else /* not HAVE_UNSIGNED_CHAR */
jpayne@69 166
jpayne@69 167 typedef char JOCTET;
jpayne@69 168 #ifdef CHAR_IS_UNSIGNED
jpayne@69 169 #define GETJOCTET(value) (value)
jpayne@69 170 #else
jpayne@69 171 #define GETJOCTET(value) ((value) & 0xFF)
jpayne@69 172 #endif /* CHAR_IS_UNSIGNED */
jpayne@69 173
jpayne@69 174 #endif /* HAVE_UNSIGNED_CHAR */
jpayne@69 175
jpayne@69 176
jpayne@69 177 /* These typedefs are used for various table entries and so forth.
jpayne@69 178 * They must be at least as wide as specified; but making them too big
jpayne@69 179 * won't cost a huge amount of memory, so we don't provide special
jpayne@69 180 * extraction code like we did for JSAMPLE. (In other words, these
jpayne@69 181 * typedefs live at a different point on the speed/space tradeoff curve.)
jpayne@69 182 */
jpayne@69 183
jpayne@69 184 /* UINT8 must hold at least the values 0..255. */
jpayne@69 185
jpayne@69 186 #ifdef HAVE_UNSIGNED_CHAR
jpayne@69 187 typedef unsigned char UINT8;
jpayne@69 188 #else /* not HAVE_UNSIGNED_CHAR */
jpayne@69 189 #ifdef CHAR_IS_UNSIGNED
jpayne@69 190 typedef char UINT8;
jpayne@69 191 #else /* not CHAR_IS_UNSIGNED */
jpayne@69 192 typedef short UINT8;
jpayne@69 193 #endif /* CHAR_IS_UNSIGNED */
jpayne@69 194 #endif /* HAVE_UNSIGNED_CHAR */
jpayne@69 195
jpayne@69 196 /* UINT16 must hold at least the values 0..65535. */
jpayne@69 197
jpayne@69 198 #ifdef HAVE_UNSIGNED_SHORT
jpayne@69 199 typedef unsigned short UINT16;
jpayne@69 200 #else /* not HAVE_UNSIGNED_SHORT */
jpayne@69 201 typedef unsigned int UINT16;
jpayne@69 202 #endif /* HAVE_UNSIGNED_SHORT */
jpayne@69 203
jpayne@69 204 /* INT16 must hold at least the values -32768..32767. */
jpayne@69 205
jpayne@69 206 #ifndef XMD_H /* X11/xmd.h correctly defines INT16 */
jpayne@69 207 typedef short INT16;
jpayne@69 208 #endif
jpayne@69 209
jpayne@69 210 /* INT32 must hold at least signed 32-bit values. */
jpayne@69 211
jpayne@69 212 #ifndef XMD_H /* X11/xmd.h correctly defines INT32 */
jpayne@69 213 #ifndef _BASETSD_H_ /* Microsoft defines it in basetsd.h */
jpayne@69 214 #ifndef _BASETSD_H /* MinGW is slightly different */
jpayne@69 215 #ifndef QGLOBAL_H /* Qt defines it in qglobal.h */
jpayne@69 216 typedef long INT32;
jpayne@69 217 #endif
jpayne@69 218 #endif
jpayne@69 219 #endif
jpayne@69 220 #endif
jpayne@69 221
jpayne@69 222 /* Datatype used for image dimensions. The JPEG standard only supports
jpayne@69 223 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore
jpayne@69 224 * "unsigned int" is sufficient on all machines. However, if you need to
jpayne@69 225 * handle larger images and you don't mind deviating from the spec, you
jpayne@69 226 * can change this datatype.
jpayne@69 227 */
jpayne@69 228
jpayne@69 229 typedef unsigned int JDIMENSION;
jpayne@69 230
jpayne@69 231 #define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */
jpayne@69 232
jpayne@69 233
jpayne@69 234 /* These macros are used in all function definitions and extern declarations.
jpayne@69 235 * You could modify them if you need to change function linkage conventions;
jpayne@69 236 * in particular, you'll need to do that to make the library a Windows DLL.
jpayne@69 237 * Another application is to make all functions global for use with debuggers
jpayne@69 238 * or code profilers that require it.
jpayne@69 239 */
jpayne@69 240
jpayne@69 241 /* a function called through method pointers: */
jpayne@69 242 #define METHODDEF(type) static type
jpayne@69 243 /* a function used only in its module: */
jpayne@69 244 #define LOCAL(type) static type
jpayne@69 245 /* a function referenced thru EXTERNs: */
jpayne@69 246 #define GLOBAL(type) type
jpayne@69 247 /* a reference to a GLOBAL function: */
jpayne@69 248 #define EXTERN(type) extern type
jpayne@69 249
jpayne@69 250
jpayne@69 251 /* This macro is used to declare a "method", that is, a function pointer.
jpayne@69 252 * We want to supply prototype parameters if the compiler can cope.
jpayne@69 253 * Note that the arglist parameter must be parenthesized!
jpayne@69 254 * Again, you can customize this if you need special linkage keywords.
jpayne@69 255 */
jpayne@69 256
jpayne@69 257 #ifdef HAVE_PROTOTYPES
jpayne@69 258 #define JMETHOD(type,methodname,arglist) type (*methodname) arglist
jpayne@69 259 #else
jpayne@69 260 #define JMETHOD(type,methodname,arglist) type (*methodname) ()
jpayne@69 261 #endif
jpayne@69 262
jpayne@69 263
jpayne@69 264 /* The noreturn type identifier is used to declare functions
jpayne@69 265 * which cannot return.
jpayne@69 266 * Compilers can thus create more optimized code and perform
jpayne@69 267 * better checks for warnings and errors.
jpayne@69 268 * Static analyzer tools can make improved inferences about
jpayne@69 269 * execution paths and are prevented from giving false alerts.
jpayne@69 270 *
jpayne@69 271 * Unfortunately, the proposed specifications of corresponding
jpayne@69 272 * extensions in the Dec 2011 ISO C standard revision (C11),
jpayne@69 273 * GCC, MSVC, etc. are not viable.
jpayne@69 274 * Thus we introduce a user defined type to declare noreturn
jpayne@69 275 * functions at least for clarity. A proper compiler would
jpayne@69 276 * have a suitable noreturn type to match in place of void.
jpayne@69 277 */
jpayne@69 278
jpayne@69 279 #ifndef HAVE_NORETURN_T
jpayne@69 280 typedef void noreturn_t;
jpayne@69 281 #endif
jpayne@69 282
jpayne@69 283
jpayne@69 284 /* Here is the pseudo-keyword for declaring pointers that must be "far"
jpayne@69 285 * on 80x86 machines. Most of the specialized coding for 80x86 is handled
jpayne@69 286 * by just saying "FAR *" where such a pointer is needed. In a few places
jpayne@69 287 * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
jpayne@69 288 */
jpayne@69 289
jpayne@69 290 #ifndef FAR
jpayne@69 291 #ifdef NEED_FAR_POINTERS
jpayne@69 292 #define FAR far
jpayne@69 293 #else
jpayne@69 294 #define FAR
jpayne@69 295 #endif
jpayne@69 296 #endif
jpayne@69 297
jpayne@69 298
jpayne@69 299 /*
jpayne@69 300 * On a few systems, type boolean and/or its values FALSE, TRUE may appear
jpayne@69 301 * in standard header files. Or you may have conflicts with application-
jpayne@69 302 * specific header files that you want to include together with these files.
jpayne@69 303 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
jpayne@69 304 */
jpayne@69 305
jpayne@69 306 #ifndef HAVE_BOOLEAN
jpayne@69 307 #if defined FALSE || defined TRUE || defined QGLOBAL_H
jpayne@69 308 /* Qt3 defines FALSE and TRUE as "const" variables in qglobal.h */
jpayne@69 309 typedef int boolean;
jpayne@69 310 #ifndef FALSE /* in case these macros already exist */
jpayne@69 311 #define FALSE 0 /* values of boolean */
jpayne@69 312 #endif
jpayne@69 313 #ifndef TRUE
jpayne@69 314 #define TRUE 1
jpayne@69 315 #endif
jpayne@69 316 #else
jpayne@69 317 typedef enum { FALSE = 0, TRUE = 1 } boolean;
jpayne@69 318 #endif
jpayne@69 319 #endif
jpayne@69 320
jpayne@69 321
jpayne@69 322 /*
jpayne@69 323 * The remaining options affect code selection within the JPEG library,
jpayne@69 324 * but they don't need to be visible to most applications using the library.
jpayne@69 325 * To minimize application namespace pollution, the symbols won't be
jpayne@69 326 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
jpayne@69 327 */
jpayne@69 328
jpayne@69 329 #ifdef JPEG_INTERNALS
jpayne@69 330 #define JPEG_INTERNAL_OPTIONS
jpayne@69 331 #endif
jpayne@69 332
jpayne@69 333 #ifdef JPEG_INTERNAL_OPTIONS
jpayne@69 334
jpayne@69 335
jpayne@69 336 /*
jpayne@69 337 * These defines indicate whether to include various optional functions.
jpayne@69 338 * Undefining some of these symbols will produce a smaller but less capable
jpayne@69 339 * library. Note that you can leave certain source files out of the
jpayne@69 340 * compilation/linking process if you've #undef'd the corresponding symbols.
jpayne@69 341 * (You may HAVE to do that if your compiler doesn't like null source files.)
jpayne@69 342 */
jpayne@69 343
jpayne@69 344 /* Capability options common to encoder and decoder: */
jpayne@69 345
jpayne@69 346 #define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */
jpayne@69 347 #define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */
jpayne@69 348 #define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */
jpayne@69 349
jpayne@69 350 /* Encoder capability options: */
jpayne@69 351
jpayne@69 352 #define C_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
jpayne@69 353 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
jpayne@69 354 #define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
jpayne@69 355 #define DCT_SCALING_SUPPORTED /* Input rescaling via DCT? (Requires DCT_ISLOW)*/
jpayne@69 356 #define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */
jpayne@69 357 /* Note: if you selected more than 8-bit data precision, it is dangerous to
jpayne@69 358 * turn off ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only
jpayne@69 359 * good for 8-bit precision, so arithmetic coding is recommended for higher
jpayne@69 360 * precision. The Huffman encoder normally uses entropy optimization to
jpayne@69 361 * compute usable tables for higher precision. Otherwise, you'll have to
jpayne@69 362 * supply different default Huffman tables.
jpayne@69 363 * The exact same statements apply for progressive JPEG: the default tables
jpayne@69 364 * don't work for progressive mode. (This may get fixed, however.)
jpayne@69 365 */
jpayne@69 366 #define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */
jpayne@69 367
jpayne@69 368 /* Decoder capability options: */
jpayne@69 369
jpayne@69 370 #define D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
jpayne@69 371 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
jpayne@69 372 #define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
jpayne@69 373 #define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? (Requires DCT_ISLOW)*/
jpayne@69 374 #define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */
jpayne@69 375 #define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */
jpayne@69 376 #undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */
jpayne@69 377 #define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */
jpayne@69 378 #define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */
jpayne@69 379 #define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */
jpayne@69 380
jpayne@69 381 /* more capability options later, no doubt */
jpayne@69 382
jpayne@69 383
jpayne@69 384 /*
jpayne@69 385 * Ordering of RGB data in scanlines passed to or from the application.
jpayne@69 386 * If your application wants to deal with data in the order B,G,R, just
jpayne@69 387 * change these macros. You can also deal with formats such as R,G,B,X
jpayne@69 388 * (one extra byte per pixel) by changing RGB_PIXELSIZE. Note that changing
jpayne@69 389 * the offsets will also change the order in which colormap data is organized.
jpayne@69 390 * RESTRICTIONS:
jpayne@69 391 * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
jpayne@69 392 * 2. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
jpayne@69 393 * is not 3 (they don't understand about dummy color components!). So you
jpayne@69 394 * can't use color quantization if you change that value.
jpayne@69 395 */
jpayne@69 396
jpayne@69 397 #define RGB_RED 0 /* Offset of Red in an RGB scanline element */
jpayne@69 398 #define RGB_GREEN 1 /* Offset of Green */
jpayne@69 399 #define RGB_BLUE 2 /* Offset of Blue */
jpayne@69 400 #define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */
jpayne@69 401
jpayne@69 402
jpayne@69 403 /* Definitions for speed-related optimizations. */
jpayne@69 404
jpayne@69 405
jpayne@69 406 /* If your compiler supports inline functions, define INLINE
jpayne@69 407 * as the inline keyword; otherwise define it as empty.
jpayne@69 408 */
jpayne@69 409
jpayne@69 410 #ifndef INLINE
jpayne@69 411 #ifdef __GNUC__ /* for instance, GNU C knows about inline */
jpayne@69 412 #define INLINE __inline__
jpayne@69 413 #endif
jpayne@69 414 #ifndef INLINE
jpayne@69 415 #define INLINE /* default is to define it as empty */
jpayne@69 416 #endif
jpayne@69 417 #endif
jpayne@69 418
jpayne@69 419
jpayne@69 420 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
jpayne@69 421 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER
jpayne@69 422 * as short on such a machine. MULTIPLIER must be at least 16 bits wide.
jpayne@69 423 */
jpayne@69 424
jpayne@69 425 #ifndef MULTIPLIER
jpayne@69 426 #define MULTIPLIER int /* type for fastest integer multiply */
jpayne@69 427 #endif
jpayne@69 428
jpayne@69 429
jpayne@69 430 /* FAST_FLOAT should be either float or double, whichever is done faster
jpayne@69 431 * by your compiler. (Note that this type is only used in the floating point
jpayne@69 432 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
jpayne@69 433 * Typically, float is faster in ANSI C compilers, while double is faster in
jpayne@69 434 * pre-ANSI compilers (because they insist on converting to double anyway).
jpayne@69 435 * The code below therefore chooses float if we have ANSI-style prototypes.
jpayne@69 436 */
jpayne@69 437
jpayne@69 438 #ifndef FAST_FLOAT
jpayne@69 439 #ifdef HAVE_PROTOTYPES
jpayne@69 440 #define FAST_FLOAT float
jpayne@69 441 #else
jpayne@69 442 #define FAST_FLOAT double
jpayne@69 443 #endif
jpayne@69 444 #endif
jpayne@69 445
jpayne@69 446 #endif /* JPEG_INTERNAL_OPTIONS */