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1/*
2 * jmorecfg.h
3 *
4 * Copyright (C) 1991-1997, Thomas G. Lane.
5 * This file is part of the Independent JPEG Group's software.
6 * For conditions of distribution and use, see the accompanying README file.
7 *
8 * This file contains additional configuration options that customize the
9 * JPEG software for special applications or support machine-dependent
10 * optimizations. Most users will not need to touch this file.
11 */
12
13
14/*
15 * Define BITS_IN_JSAMPLE as either
16 * 8 for 8-bit sample values (the usual setting)
17 * 12 for 12-bit sample values
18 * Only 8 and 12 are legal data precisions for lossy JPEG according to the
19 * JPEG standard, and the IJG code does not support anything else!
20 * We do not support run-time selection of data precision, sorry.
21 */
22
23#define BITS_IN_JSAMPLE 8 /* use 8 or 12 */
24
25
26/*
27 * Maximum number of components (color channels) allowed in JPEG image.
28 * To meet the letter of the JPEG spec, set this to 255. However, darn
29 * few applications need more than 4 channels (maybe 5 for CMYK + alpha
30 * mask). We recommend 10 as a reasonable compromise; use 4 if you are
31 * really short on memory. (Each allowed component costs a hundred or so
32 * bytes of storage, whether actually used in an image or not.)
33 */
34
35#define MAX_COMPONENTS 10 /* maximum number of image components */
36
37
38/*
39 * Basic data types.
40 * You may need to change these if you have a machine with unusual data
41 * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
42 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits,
43 * but it had better be at least 16.
44 */
45
46/* Representation of a single sample (pixel element value).
47 * We frequently allocate large arrays of these, so it's important to keep
48 * them small. But if you have memory to burn and access to char or short
49 * arrays is very slow on your hardware, you might want to change these.
50 */
51
52#if BITS_IN_JSAMPLE == 8
53/* JSAMPLE should be the smallest type that will hold the values 0..255.
54 * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
55 */
56
57#ifdef HAVE_UNSIGNED_CHAR
58
59typedef unsigned char JSAMPLE;
60#define GETJSAMPLE(value) ((int) (value))
61
62#else /* not HAVE_UNSIGNED_CHAR */
63
64typedef char JSAMPLE;
65#ifdef CHAR_IS_UNSIGNED
66#define GETJSAMPLE(value) ((int) (value))
67#else
68#define GETJSAMPLE(value) ((int) (value) & 0xFF)
69#endif /* CHAR_IS_UNSIGNED */
70
71#endif /* HAVE_UNSIGNED_CHAR */
72
73#define MAXJSAMPLE 255
74#define CENTERJSAMPLE 128
75
76#endif /* BITS_IN_JSAMPLE == 8 */
77
78
79#if BITS_IN_JSAMPLE == 12
80/* JSAMPLE should be the smallest type that will hold the values 0..4095.
81 * On nearly all machines "short" will do nicely.
82 */
83
84typedef short JSAMPLE;
85#define GETJSAMPLE(value) ((int) (value))
86
87#define MAXJSAMPLE 4095
88#define CENTERJSAMPLE 2048
89
90#endif /* BITS_IN_JSAMPLE == 12 */
91
92
93/* Representation of a DCT frequency coefficient.
94 * This should be a signed value of at least 16 bits; "short" is usually OK.
95 * Again, we allocate large arrays of these, but you can change to int
96 * if you have memory to burn and "short" is really slow.
97 */
98
99typedef short JCOEF;
100
101
102/* Compressed datastreams are represented as arrays of JOCTET.
103 * These must be EXACTLY 8 bits wide, at least once they are written to
104 * external storage. Note that when using the stdio data source/destination
105 * managers, this is also the data type passed to fread/fwrite.
106 */
107
108#ifdef HAVE_UNSIGNED_CHAR
109
110typedef unsigned char JOCTET;
111#define GETJOCTET(value) (value)
112
113#else /* not HAVE_UNSIGNED_CHAR */
114
115typedef char JOCTET;
116#ifdef CHAR_IS_UNSIGNED
117#define GETJOCTET(value) (value)
118#else
119#define GETJOCTET(value) ((value) & 0xFF)
120#endif /* CHAR_IS_UNSIGNED */
121
122#endif /* HAVE_UNSIGNED_CHAR */
123
124
125/* These typedefs are used for various table entries and so forth.
126 * They must be at least as wide as specified; but making them too big
127 * won't cost a huge amount of memory, so we don't provide special
128 * extraction code like we did for JSAMPLE. (In other words, these
129 * typedefs live at a different point on the speed/space tradeoff curve.)
130 */
131
132/* UINT8 must hold at least the values 0..255. */
5283098e 133#ifndef __WINE_BASETSD_H
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134
135#ifdef HAVE_UNSIGNED_CHAR
136typedef unsigned char UINT8;
137#else /* not HAVE_UNSIGNED_CHAR */
138#ifdef CHAR_IS_UNSIGNED
139typedef char UINT8;
140#else /* not CHAR_IS_UNSIGNED */
141typedef short UINT8;
142#endif /* CHAR_IS_UNSIGNED */
143#endif /* HAVE_UNSIGNED_CHAR */
144
145/* UINT16 must hold at least the values 0..65535. */
146
147#ifdef HAVE_UNSIGNED_SHORT
148typedef unsigned short UINT16;
149#else /* not HAVE_UNSIGNED_SHORT */
150typedef unsigned int UINT16;
151#endif /* HAVE_UNSIGNED_SHORT */
152
153/* INT16 must hold at least the values -32768..32767. */
154
155#ifndef XMD_H /* X11/xmd.h correctly defines INT16 */
156typedef short INT16;
157#endif
158
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159#endif /* __WINE_BASETSD_H */
160
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161/* INT32 must hold at least signed 32-bit values. */
162
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163/*
164 VZ: due to the horrible mess resulting in INT32 being defined in windows.h
165 for some compilers but not for the other ones, I have globally replace
166 INT32 with JPEG_INT32 in libjpeg code to avoid the eight level ifdef
167 which used to be here. The problem is that, of course, now we'll have
168 conflicts when upgrading to the next libjpeg release -- however
169 considering their frequency (1 in the last 5 years) it seems that
170 it is not too high a price to pay for the clean compilation with all
171 versions of mingw32 and cygwin
172 */
173typedef long JPEG_INT32;
ae128b35 174
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175/* Datatype used for image dimensions. The JPEG standard only supports
176 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore
177 * "unsigned int" is sufficient on all machines. However, if you need to
178 * handle larger images and you don't mind deviating from the spec, you
179 * can change this datatype.
180 */
181
182typedef unsigned int JDIMENSION;
183
184#define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */
185
186
187/* These macros are used in all function definitions and extern declarations.
188 * You could modify them if you need to change function linkage conventions;
189 * in particular, you'll need to do that to make the library a Windows DLL.
190 * Another application is to make all functions global for use with debuggers
191 * or code profilers that require it.
192 */
193
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194#if defined(__VISAGECPP__)
195#define JPEG_CALLING_CONV _Optlink
196#else /* !Visual Age C++ */
197#define JPEG_CALLING_CONV
198#endif
199
200/* We can't declare a static function as extern "C" as we need to do in C++
201 * programs, so suppress static in METHODDEF when using C++.
202 */
203#if defined(__cplusplus)
204#define JPEG_METHOD_LINKAGE
205#else /* !__cplusplus */
206#define JPEG_METHOD_LINKAGE static
207#endif
208
e1929140 209/* a function called through method pointers: */
d7c42914 210#define METHODDEF(type) JPEG_METHOD_LINKAGE type JPEG_CALLING_CONV
e1929140 211/* a function used only in its module: */
d7c42914 212#define LOCAL(type) static type JPEG_CALLING_CONV
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213/* a function referenced thru EXTERNs: */
214#define GLOBAL(type) type
215/* a reference to a GLOBAL function: */
d7c42914 216#define EXTERN(type) extern type JPEG_CALLING_CONV
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217
218/* This macro is used to declare a "method", that is, a function pointer.
219 * We want to supply prototype parameters if the compiler can cope.
220 * Note that the arglist parameter must be parenthesized!
221 * Again, you can customize this if you need special linkage keywords.
222 */
223
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224#if defined(__VISAGECPP__) /* need this for /common/imagjpeg.obj but not loclly */
225#ifdef HAVE_PROTOTYPES
226#define JMETHOD(type,methodname,arglist) type (_Optlink *methodname) arglist
227#else
228#define JMETHOD(type,methodname,arglist) type (_Optlink *methodname) ()
229#endif
230
231#else
232
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233#ifdef HAVE_PROTOTYPES
234#define JMETHOD(type,methodname,arglist) type (*methodname) arglist
235#else
236#define JMETHOD(type,methodname,arglist) type (*methodname) ()
237#endif
238
413098d0 239#endif
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240
241/* Here is the pseudo-keyword for declaring pointers that must be "far"
242 * on 80x86 machines. Most of the specialized coding for 80x86 is handled
243 * by just saying "FAR *" where such a pointer is needed. In a few places
244 * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
245 */
246
247#ifdef NEED_FAR_POINTERS
248#define FAR far
249#else
9c824f29 250#ifndef FAR
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251#define FAR
252#endif
9c824f29 253#endif
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254
255
256/*
257 * On a few systems, type boolean and/or its values FALSE, TRUE may appear
258 * in standard header files. Or you may have conflicts with application-
259 * specific header files that you want to include together with these files.
260 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
261 */
262
e604ac79 263#if 0
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264#ifndef HAVE_BOOLEAN
265typedef int boolean;
266#endif
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267#endif
268
269/*
270 * Notes about boolean above:
271 *
272 * The main conflict we see is with the Windows headers of some compilers that
273 * have a different definition of boolean. Therefore boolean has been replaced
274 * with wxjpeg_boolean throughout the jpeg sources. The alternative would have
275 * been to make the definition here the same as the Windows definition. It's
276 * not enough to just define HAVE_BOOLEAN when using the jpeg library, the
277 * definition of boolean must match when the jpeg library is compiled too.
278 *
279 * System jepg libs won't have this type, of course, so to use test
280 * HAVE_WXJPEG_BOOLEAN and fall back to boolean when not defined.
281 */
282
283typedef int wxjpeg_boolean;
284#define HAVE_WXJPEG_BOOLEAN
285
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286#ifndef FALSE /* in case these macros already exist */
287#define FALSE 0 /* values of boolean */
288#endif
289#ifndef TRUE
290#define TRUE 1
291#endif
292
293
294/*
295 * The remaining options affect code selection within the JPEG library,
296 * but they don't need to be visible to most applications using the library.
297 * To minimize application namespace pollution, the symbols won't be
298 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
299 */
300
301#ifdef JPEG_INTERNALS
302#define JPEG_INTERNAL_OPTIONS
303#endif
304
305#ifdef JPEG_INTERNAL_OPTIONS
306
307
308/*
309 * These defines indicate whether to include various optional functions.
310 * Undefining some of these symbols will produce a smaller but less capable
311 * library. Note that you can leave certain source files out of the
312 * compilation/linking process if you've #undef'd the corresponding symbols.
313 * (You may HAVE to do that if your compiler doesn't like null source files.)
314 */
315
316/* Arithmetic coding is unsupported for legal reasons. Complaints to IBM. */
317
318/* Capability options common to encoder and decoder: */
319
320#define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */
321#define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */
322#define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */
323
324/* Encoder capability options: */
325
326#undef C_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
327#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
328#define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
329#define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */
330/* Note: if you selected 12-bit data precision, it is dangerous to turn off
331 * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit
332 * precision, so jchuff.c normally uses entropy optimization to compute
333 * usable tables for higher precision. If you don't want to do optimization,
334 * you'll have to supply different default Huffman tables.
335 * The exact same statements apply for progressive JPEG: the default tables
336 * don't work for progressive mode. (This may get fixed, however.)
337 */
338#define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */
339
340/* Decoder capability options: */
341
342#undef D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
343#define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
344#define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
345#define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */
346#define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */
347#define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */
348#undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */
349#define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */
350#define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */
351#define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */
352
353/* more capability options later, no doubt */
354
355
356/*
357 * Ordering of RGB data in scanlines passed to or from the application.
358 * If your application wants to deal with data in the order B,G,R, just
359 * change these macros. You can also deal with formats such as R,G,B,X
360 * (one extra byte per pixel) by changing RGB_PIXELSIZE. Note that changing
361 * the offsets will also change the order in which colormap data is organized.
362 * RESTRICTIONS:
363 * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
364 * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not
365 * useful if you are using JPEG color spaces other than YCbCr or grayscale.
366 * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
367 * is not 3 (they don't understand about dummy color components!). So you
368 * can't use color quantization if you change that value.
369 */
370
371#define RGB_RED 0 /* Offset of Red in an RGB scanline element */
372#define RGB_GREEN 1 /* Offset of Green */
373#define RGB_BLUE 2 /* Offset of Blue */
374#define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */
375
376
377/* Definitions for speed-related optimizations. */
378
379
380/* If your compiler supports inline functions, define INLINE
381 * as the inline keyword; otherwise define it as empty.
382 */
383
384#ifndef INLINE
385#ifdef __GNUC__ /* for instance, GNU C knows about inline */
386#define INLINE __inline__
387#endif
388#ifndef INLINE
389#define INLINE /* default is to define it as empty */
390#endif
391#endif
392
393
394/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
395 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER
396 * as short on such a machine. MULTIPLIER must be at least 16 bits wide.
397 */
398
399#ifndef MULTIPLIER
400#define MULTIPLIER int /* type for fastest integer multiply */
401#endif
402
403
404/* FAST_FLOAT should be either float or double, whichever is done faster
405 * by your compiler. (Note that this type is only used in the floating point
406 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
407 * Typically, float is faster in ANSI C compilers, while double is faster in
408 * pre-ANSI compilers (because they insist on converting to double anyway).
409 * The code below therefore chooses float if we have ANSI-style prototypes.
410 */
411
412#ifndef FAST_FLOAT
413#ifdef HAVE_PROTOTYPES
414#define FAST_FLOAT float
415#else
416#define FAST_FLOAT double
417#endif
418#endif
419
420#endif /* JPEG_INTERNAL_OPTIONS */