ReactOS 0.4.15-dev-5884-gab5aff5
jmorecfg.h
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1/*
2 * jmorecfg.h
3 *
4 * Copyright (C) 1991-1997, Thomas G. Lane.
5 * Modified 1997-2013 by Guido Vollbeding.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
8 *
9 * This file contains additional configuration options that customize the
10 * JPEG software for special applications or support machine-dependent
11 * optimizations. Most users will not need to touch this file.
12 */
13
14
15/*
16 * Define BITS_IN_JSAMPLE as either
17 * 8 for 8-bit sample values (the usual setting)
18 * 9 for 9-bit sample values
19 * 10 for 10-bit sample values
20 * 11 for 11-bit sample values
21 * 12 for 12-bit sample values
22 * Only 8, 9, 10, 11, and 12 bits sample data precision are supported for
23 * full-feature DCT processing. Further depths up to 16-bit may be added
24 * later for the lossless modes of operation.
25 * Run-time selection and conversion of data precision will be added later
26 * and are currently not supported, sorry.
27 * Exception: The transcoding part (jpegtran) supports all settings in a
28 * single instance, since it operates on the level of DCT coefficients and
29 * not sample values. The DCT coefficients are of the same type (16 bits)
30 * in all cases (see below).
31 */
32
33#define BITS_IN_JSAMPLE 8 /* use 8, 9, 10, 11, or 12 */
34
35
36/*
37 * Maximum number of components (color channels) allowed in JPEG image.
38 * To meet the letter of the JPEG spec, set this to 255. However, darn
39 * few applications need more than 4 channels (maybe 5 for CMYK + alpha
40 * mask). We recommend 10 as a reasonable compromise; use 4 if you are
41 * really short on memory. (Each allowed component costs a hundred or so
42 * bytes of storage, whether actually used in an image or not.)
43 */
44
45#define MAX_COMPONENTS 10 /* maximum number of image components */
46
47
48/*
49 * Basic data types.
50 * You may need to change these if you have a machine with unusual data
51 * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
52 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits,
53 * but it had better be at least 16.
54 */
55
56/* Representation of a single sample (pixel element value).
57 * We frequently allocate large arrays of these, so it's important to keep
58 * them small. But if you have memory to burn and access to char or short
59 * arrays is very slow on your hardware, you might want to change these.
60 */
61
62#if BITS_IN_JSAMPLE == 8
63/* JSAMPLE should be the smallest type that will hold the values 0..255.
64 * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
65 */
66
67#ifdef HAVE_UNSIGNED_CHAR
68
69typedef unsigned char JSAMPLE;
70#define GETJSAMPLE(value) ((int) (value))
71
72#else /* not HAVE_UNSIGNED_CHAR */
73
74typedef char JSAMPLE;
75#ifdef CHAR_IS_UNSIGNED
76#define GETJSAMPLE(value) ((int) (value))
77#else
78#define GETJSAMPLE(value) ((int) (value) & 0xFF)
79#endif /* CHAR_IS_UNSIGNED */
80
81#endif /* HAVE_UNSIGNED_CHAR */
82
83#define MAXJSAMPLE 255
84#define CENTERJSAMPLE 128
85
86#endif /* BITS_IN_JSAMPLE == 8 */
87
88
89#if BITS_IN_JSAMPLE == 9
90/* JSAMPLE should be the smallest type that will hold the values 0..511.
91 * On nearly all machines "short" will do nicely.
92 */
93
94typedef short JSAMPLE;
95#define GETJSAMPLE(value) ((int) (value))
96
97#define MAXJSAMPLE 511
98#define CENTERJSAMPLE 256
99
100#endif /* BITS_IN_JSAMPLE == 9 */
101
102
103#if BITS_IN_JSAMPLE == 10
104/* JSAMPLE should be the smallest type that will hold the values 0..1023.
105 * On nearly all machines "short" will do nicely.
106 */
107
108typedef short JSAMPLE;
109#define GETJSAMPLE(value) ((int) (value))
110
111#define MAXJSAMPLE 1023
112#define CENTERJSAMPLE 512
113
114#endif /* BITS_IN_JSAMPLE == 10 */
115
116
117#if BITS_IN_JSAMPLE == 11
118/* JSAMPLE should be the smallest type that will hold the values 0..2047.
119 * On nearly all machines "short" will do nicely.
120 */
121
122typedef short JSAMPLE;
123#define GETJSAMPLE(value) ((int) (value))
124
125#define MAXJSAMPLE 2047
126#define CENTERJSAMPLE 1024
127
128#endif /* BITS_IN_JSAMPLE == 11 */
129
130
131#if BITS_IN_JSAMPLE == 12
132/* JSAMPLE should be the smallest type that will hold the values 0..4095.
133 * On nearly all machines "short" will do nicely.
134 */
135
136typedef short JSAMPLE;
137#define GETJSAMPLE(value) ((int) (value))
138
139#define MAXJSAMPLE 4095
140#define CENTERJSAMPLE 2048
141
142#endif /* BITS_IN_JSAMPLE == 12 */
143
144
145/* Representation of a DCT frequency coefficient.
146 * This should be a signed value of at least 16 bits; "short" is usually OK.
147 * Again, we allocate large arrays of these, but you can change to int
148 * if you have memory to burn and "short" is really slow.
149 */
150
151typedef short JCOEF;
152
153
154/* Compressed datastreams are represented as arrays of JOCTET.
155 * These must be EXACTLY 8 bits wide, at least once they are written to
156 * external storage. Note that when using the stdio data source/destination
157 * managers, this is also the data type passed to fread/fwrite.
158 */
159
160#ifdef HAVE_UNSIGNED_CHAR
161
162typedef unsigned char JOCTET;
163#define GETJOCTET(value) (value)
164
165#else /* not HAVE_UNSIGNED_CHAR */
166
167typedef char JOCTET;
168#ifdef CHAR_IS_UNSIGNED
169#define GETJOCTET(value) (value)
170#else
171#define GETJOCTET(value) ((value) & 0xFF)
172#endif /* CHAR_IS_UNSIGNED */
173
174#endif /* HAVE_UNSIGNED_CHAR */
175
176
177/* These typedefs are used for various table entries and so forth.
178 * They must be at least as wide as specified; but making them too big
179 * won't cost a huge amount of memory, so we don't provide special
180 * extraction code like we did for JSAMPLE. (In other words, these
181 * typedefs live at a different point on the speed/space tradeoff curve.)
182 */
183
184/* UINT8 must hold at least the values 0..255. */
185
186#ifdef HAVE_UNSIGNED_CHAR
187typedef unsigned char UINT8;
188#else /* not HAVE_UNSIGNED_CHAR */
189#ifdef CHAR_IS_UNSIGNED
190typedef char UINT8;
191#else /* not CHAR_IS_UNSIGNED */
192typedef short UINT8;
193#endif /* CHAR_IS_UNSIGNED */
194#endif /* HAVE_UNSIGNED_CHAR */
195
196/* UINT16 must hold at least the values 0..65535. */
197
198#ifdef HAVE_UNSIGNED_SHORT
199typedef unsigned short UINT16;
200#else /* not HAVE_UNSIGNED_SHORT */
201typedef unsigned int UINT16;
202#endif /* HAVE_UNSIGNED_SHORT */
203
204/* INT16 must hold at least the values -32768..32767. */
205
206#ifndef XMD_H /* X11/xmd.h correctly defines INT16 */
207typedef short INT16;
208#endif
209
210/* INT32 must hold at least signed 32-bit values. */
211
212#ifndef XMD_H /* X11/xmd.h correctly defines INT32 */
213#ifndef _BASETSD_H_ /* Microsoft defines it in basetsd.h */
214#ifndef _BASETSD_H /* MinGW is slightly different */
215#ifndef QGLOBAL_H /* Qt defines it in qglobal.h */
216typedef long INT32;
217#endif
218#endif
219#endif
220#endif
221
222/* Datatype used for image dimensions. The JPEG standard only supports
223 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore
224 * "unsigned int" is sufficient on all machines. However, if you need to
225 * handle larger images and you don't mind deviating from the spec, you
226 * can change this datatype.
227 */
228
229typedef unsigned int JDIMENSION;
230
231#define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */
232
233
234/* These macros are used in all function definitions and extern declarations.
235 * You could modify them if you need to change function linkage conventions;
236 * in particular, you'll need to do that to make the library a Windows DLL.
237 * Another application is to make all functions global for use with debuggers
238 * or code profilers that require it.
239 */
240
241#ifdef _WIN32
242# if defined(ALL_STATIC)
243# if defined(JPEG_DLL)
244# undef JPEG_DLL
245# endif
246# if !defined(JPEG_STATIC)
247# define JPEG_STATIC
248# endif
249# endif
250# if defined(JPEG_DLL)
251# if defined(JPEG_STATIC)
252# undef JPEG_STATIC
253# endif
254# endif
255# if defined(JPEG_DLL)
256/* building a DLL */
257# define JPEG_IMPEXP __declspec(dllexport)
258# elif defined(JPEG_STATIC)
259/* building or linking to a static library */
260# define JPEG_IMPEXP
261# else
262/* linking to the DLL */
263# define JPEG_IMPEXP __declspec(dllimport)
264# endif
265# if !defined(JPEG_API)
266# define JPEG_API __cdecl
267# endif
268/* The only remaining magic that is necessary for cygwin */
269#elif defined(__CYGWIN__)
270# if !defined(JPEG_IMPEXP)
271# define JPEG_IMPEXP
272# endif
273# if !defined(JPEG_API)
274# define JPEG_API __cdecl
275# endif
276#endif
277
278/* Ensure our magic doesn't hurt other platforms */
279#if !defined(JPEG_IMPEXP)
280# define JPEG_IMPEXP
281#endif
282#if !defined(JPEG_API)
283# define JPEG_API
284#endif
285
286/* a function called through method pointers: */
287#define METHODDEF(type) static type
288/* a function used only in its module: */
289#define LOCAL(type) static type
290/* a function referenced thru EXTERNs: */
291#define GLOBAL(type) type JPEG_API
292/* a reference to a GLOBAL function: */
293#ifndef EXTERN
294# define EXTERN(type) extern JPEG_IMPEXP type JPEG_API
295/* a reference to a "GLOBAL" function exported by sourcefiles of utility progs */
296#endif /* EXTERN */
297
298
299/* This macro is used to declare a "method", that is, a function pointer.
300 * We want to supply prototype parameters if the compiler can cope.
301 * Note that the arglist parameter must be parenthesized!
302 * Again, you can customize this if you need special linkage keywords.
303 */
304
305#ifdef HAVE_PROTOTYPES
306#define JMETHOD(type,methodname,arglist) type (*methodname) arglist
307#else
308#define JMETHOD(type,methodname,arglist) type (*methodname) ()
309#endif
310
311
312/* The noreturn type identifier is used to declare functions
313 * which cannot return.
314 * Compilers can thus create more optimized code and perform
315 * better checks for warnings and errors.
316 * Static analyzer tools can make improved inferences about
317 * execution paths and are prevented from giving false alerts.
318 *
319 * Unfortunately, the proposed specifications of corresponding
320 * extensions in the Dec 2011 ISO C standard revision (C11),
321 * GCC, MSVC, etc. are not viable.
322 * Thus we introduce a user defined type to declare noreturn
323 * functions at least for clarity. A proper compiler would
324 * have a suitable noreturn type to match in place of void.
325 */
326
327#ifndef HAVE_NORETURN_T
328typedef void noreturn_t;
329#endif
330
331
332/* Here is the pseudo-keyword for declaring pointers that must be "far"
333 * on 80x86 machines. Most of the specialized coding for 80x86 is handled
334 * by just saying "FAR *" where such a pointer is needed. In a few places
335 * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
336 */
337
338#ifndef FAR
339#ifdef NEED_FAR_POINTERS
340#define FAR far
341#else
342#define FAR
343#endif
344#endif
345
346
347/*
348 * On a few systems, type boolean and/or its values FALSE, TRUE may appear
349 * in standard header files. Or you may have conflicts with application-
350 * specific header files that you want to include together with these files.
351 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
352 */
353
354#ifndef HAVE_BOOLEAN
355#if defined FALSE || defined TRUE || defined QGLOBAL_H
356/* Qt3 defines FALSE and TRUE as "const" variables in qglobal.h */
357typedef int boolean;
358#ifndef FALSE /* in case these macros already exist */
359#define FALSE 0 /* values of boolean */
360#endif
361#ifndef TRUE
362#define TRUE 1
363#endif
364#else
365typedef enum { FALSE = 0, TRUE = 1 } boolean;
366#endif
367#endif
368
369
370/*
371 * The remaining options affect code selection within the JPEG library,
372 * but they don't need to be visible to most applications using the library.
373 * To minimize application namespace pollution, the symbols won't be
374 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
375 */
376
377#ifdef JPEG_INTERNALS
378#define JPEG_INTERNAL_OPTIONS
379#endif
380
381#ifdef JPEG_INTERNAL_OPTIONS
382
383
384/*
385 * These defines indicate whether to include various optional functions.
386 * Undefining some of these symbols will produce a smaller but less capable
387 * library. Note that you can leave certain source files out of the
388 * compilation/linking process if you've #undef'd the corresponding symbols.
389 * (You may HAVE to do that if your compiler doesn't like null source files.)
390 */
391
392/* Capability options common to encoder and decoder: */
393
394#define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */
395#define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */
396#define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */
397
398/* Encoder capability options: */
399
400#define C_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
401#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
402#define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
403#define DCT_SCALING_SUPPORTED /* Input rescaling via DCT? (Requires DCT_ISLOW)*/
404#define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */
405/* Note: if you selected more than 8-bit data precision, it is dangerous to
406 * turn off ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only
407 * good for 8-bit precision, so arithmetic coding is recommended for higher
408 * precision. The Huffman encoder normally uses entropy optimization to
409 * compute usable tables for higher precision. Otherwise, you'll have to
410 * supply different default Huffman tables.
411 * The exact same statements apply for progressive JPEG: the default tables
412 * don't work for progressive mode. (This may get fixed, however.)
413 */
414#define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */
415
416/* Decoder capability options: */
417
418#define D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
419#define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
420#define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
421#define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? (Requires DCT_ISLOW)*/
422#define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */
423#define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */
424#undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */
425#define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */
426#define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */
427#define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */
428
429/* more capability options later, no doubt */
430
431
432/*
433 * Ordering of RGB data in scanlines passed to or from the application.
434 * If your application wants to deal with data in the order B,G,R, just
435 * change these macros. You can also deal with formats such as R,G,B,X
436 * (one extra byte per pixel) by changing RGB_PIXELSIZE. Note that changing
437 * the offsets will also change the order in which colormap data is organized.
438 * RESTRICTIONS:
439 * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
440 * 2. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
441 * is not 3 (they don't understand about dummy color components!). So you
442 * can't use color quantization if you change that value.
443 */
444
445#define RGB_RED 0 /* Offset of Red in an RGB scanline element */
446#define RGB_GREEN 1 /* Offset of Green */
447#define RGB_BLUE 2 /* Offset of Blue */
448#define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */
449
450
451/* Definitions for speed-related optimizations. */
452
453
454/* If your compiler supports inline functions, define INLINE
455 * as the inline keyword; otherwise define it as empty.
456 */
457
458#ifndef INLINE
459#ifdef __GNUC__ /* for instance, GNU C knows about inline */
460#define INLINE __inline__
461#endif
462#ifndef INLINE
463#define INLINE /* default is to define it as empty */
464#endif
465#endif
466
467
468/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
469 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER
470 * as short on such a machine. MULTIPLIER must be at least 16 bits wide.
471 */
472
473#ifndef MULTIPLIER
474#define MULTIPLIER int /* type for fastest integer multiply */
475#endif
476
477
478/* FAST_FLOAT should be either float or double, whichever is done faster
479 * by your compiler. (Note that this type is only used in the floating point
480 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
481 * Typically, float is faster in ANSI C compilers, while double is faster in
482 * pre-ANSI compilers (because they insist on converting to double anyway).
483 * The code below therefore chooses float if we have ANSI-style prototypes.
484 */
485
486#ifndef FAST_FLOAT
487#ifdef HAVE_PROTOTYPES
488#define FAST_FLOAT float
489#else
490#define FAST_FLOAT double
491#endif
492#endif
493
494#endif /* JPEG_INTERNAL_OPTIONS */
unsigned int JDIMENSION
Definition: jmorecfg.h:229
long INT32
Definition: jmorecfg.h:216
char JOCTET
Definition: jmorecfg.h:167
char JSAMPLE
Definition: jmorecfg.h:74
short INT16
Definition: jmorecfg.h:207
boolean
Definition: jmorecfg.h:365
@ FALSE
Definition: jmorecfg.h:365
@ TRUE
Definition: jmorecfg.h:365
unsigned int UINT16
Definition: jmorecfg.h:201
void noreturn_t
Definition: jmorecfg.h:328
short UINT8
Definition: jmorecfg.h:192
short JCOEF
Definition: jmorecfg.h:151