media/libjpeg/jmorecfg.h

   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 */