source: golgotha/src/i4/loaders/jpg/jmorecfg.h @ 80

Last change on this file since 80 was 80, checked in by Sam Hocevar, 11 years ago
  • Adding the Golgotha source code. Not sure what's going to be interesting in there, but since it's all public domain, there's certainly stuff to pick up.
  • Property svn:keywords set to Id
File size: 12.5 KB
Line 
1/*
2 * jmorecfg.h
3 *
4 * Copyright (C) 1991-1996, 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. */
133
134#ifdef HAVE_UNSIGNED_CHAR
135typedef unsigned char UINT8;
136#else /* not HAVE_UNSIGNED_CHAR */
137#ifdef CHAR_IS_UNSIGNED
138typedef char UINT8;
139#else /* not CHAR_IS_UNSIGNED */
140typedef short UINT8;
141#endif /* CHAR_IS_UNSIGNED */
142#endif /* HAVE_UNSIGNED_CHAR */
143
144/* UINT16 must hold at least the values 0..65535. */
145
146#ifdef HAVE_UNSIGNED_SHORT
147typedef unsigned short UINT16;
148#else /* not HAVE_UNSIGNED_SHORT */
149typedef unsigned int UINT16;
150#endif /* HAVE_UNSIGNED_SHORT */
151
152/* INT16 must hold at least the values -32768..32767. */
153
154#ifndef XMD_H                   /* X11/xmd.h correctly defines INT16 */
155typedef short INT16;
156#endif
157
158/* INT32 must hold at least signed 32-bit values. */
159
160#ifndef XMD_H                   /* X11/xmd.h correctly defines INT32 */
161typedef long INT32;
162#endif
163
164/* Datatype used for image dimensions.  The JPEG standard only supports
165 * images up to 64K*64K due to 16-bit fields in SOF markers.  Therefore
166 * "unsigned int" is sufficient on all machines.  However, if you need to
167 * handle larger images and you don't mind deviating from the spec, you
168 * can change this datatype.
169 */
170
171typedef unsigned int JDIMENSION;
172
173#define JPEG_MAX_DIMENSION  65500L  /* a tad under 64K to prevent overflows */
174
175
176/* These macros are used in all function definitions and extern declarations.
177 * You could modify them if you need to change function linkage conventions;
178 * in particular, you'll need to do that to make the library a Windows DLL.
179 * Another application is to make all functions global for use with debuggers
180 * or code profilers that require it.
181 */
182
183/* a function called through method pointers: */
184#define METHODDEF(type)         static type
185/* a function used only in its module: */
186#define LOCAL(type)             static type
187/* a function referenced thru EXTERNs: */
188#define GLOBAL(type)            type
189/* a reference to a GLOBAL function: */
190#define EXTERN(type)            extern type
191
192
193/* This macro is used to declare a "method", that is, a function pointer.
194 * We want to supply prototype parameters if the compiler can cope.
195 * Note that the arglist parameter must be parenthesized!
196 * Again, you can customize this if you need special linkage keywords.
197 */
198
199#ifdef HAVE_PROTOTYPES
200#define JMETHOD(type,methodname,arglist)  type (*methodname) arglist
201#else
202#define JMETHOD(type,methodname,arglist)  type (*methodname) ()
203#endif
204
205
206/* Here is the pseudo-keyword for declaring pointers that must be "far"
207 * on 80x86 machines.  Most of the specialized coding for 80x86 is handled
208 * by just saying "FAR *" where such a pointer is needed.  In a few places
209 * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
210 */
211
212#ifdef NEED_FAR_POINTERS
213#define FAR  far
214#else
215#ifndef FAR
216#define FAR
217#endif
218#endif
219
220
221/*
222 * On a few systems, type boolean and/or its values FALSE, TRUE may appear
223 * in standard header files.  Or you may have conflicts with application-
224 * specific header files that you want to include together with these files.
225 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
226 */
227
228#ifndef HAVE_BOOLEAN
229typedef int boolean;
230#endif
231#ifndef FALSE                   /* in case these macros already exist */
232#define FALSE   0               /* values of boolean */
233#endif
234#ifndef TRUE
235#define TRUE    1
236#endif
237
238
239/*
240 * The remaining options affect code selection within the JPEG library,
241 * but they don't need to be visible to most applications using the library.
242 * To minimize application namespace pollution, the symbols won't be
243 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
244 */
245
246#ifdef JPEG_INTERNALS
247#define JPEG_INTERNAL_OPTIONS
248#endif
249
250#ifdef JPEG_INTERNAL_OPTIONS
251
252
253/*
254 * These defines indicate whether to include various optional functions.
255 * Undefining some of these symbols will produce a smaller but less capable
256 * library.  Note that you can leave certain source files out of the
257 * compilation/linking process if you've #undef'd the corresponding symbols.
258 * (You may HAVE to do that if your compiler doesn't like null source files.)
259 */
260
261/* Arithmetic coding is unsupported for legal reasons.  Complaints to IBM. */
262
263/* Capability options common to encoder and decoder: */
264
265#define DCT_ISLOW_SUPPORTED     /* slow but accurate integer algorithm */
266#define DCT_IFAST_SUPPORTED     /* faster, less accurate integer method */
267#define DCT_FLOAT_SUPPORTED     /* floating-point: accurate, fast on fast HW */
268
269/* Encoder capability options: */
270
271#undef  C_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */
272#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
273#define C_PROGRESSIVE_SUPPORTED     /* Progressive JPEG? (Requires MULTISCAN)*/
274#define ENTROPY_OPT_SUPPORTED       /* Optimization of entropy coding parms? */
275/* Note: if you selected 12-bit data precision, it is dangerous to turn off
276 * ENTROPY_OPT_SUPPORTED.  The standard Huffman tables are only good for 8-bit
277 * precision, so jchuff.c normally uses entropy optimization to compute
278 * usable tables for higher precision.  If you don't want to do optimization,
279 * you'll have to supply different default Huffman tables.
280 * The exact same statements apply for progressive JPEG: the default tables
281 * don't work for progressive mode.  (This may get fixed, however.)
282 */
283#define INPUT_SMOOTHING_SUPPORTED   /* Input image smoothing option? */
284
285/* Decoder capability options: */
286
287#undef  D_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */
288#define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
289#define D_PROGRESSIVE_SUPPORTED     /* Progressive JPEG? (Requires MULTISCAN)*/
290#define BLOCK_SMOOTHING_SUPPORTED   /* Block smoothing? (Progressive only) */
291#define IDCT_SCALING_SUPPORTED      /* Output rescaling via IDCT? */
292#undef  UPSAMPLE_SCALING_SUPPORTED  /* Output rescaling at upsample stage? */
293#define UPSAMPLE_MERGING_SUPPORTED  /* Fast path for sloppy upsampling? */
294#define QUANT_1PASS_SUPPORTED       /* 1-pass color quantization? */
295#define QUANT_2PASS_SUPPORTED       /* 2-pass color quantization? */
296
297/* more capability options later, no doubt */
298
299
300/*
301 * Ordering of RGB data in scanlines passed to or from the application.
302 * If your application wants to deal with data in the order B,G,R, just
303 * change these macros.  You can also deal with formats such as R,G,B,X
304 * (one extra byte per pixel) by changing RGB_PIXELSIZE.  Note that changing
305 * the offsets will also change the order in which colormap data is organized.
306 * RESTRICTIONS:
307 * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
308 * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not
309 *    useful if you are using JPEG color spaces other than YCbCr or grayscale.
310 * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
311 *    is not 3 (they don't understand about dummy color components!).  So you
312 *    can't use color quantization if you change that value.
313 */
314
315#define RGB_RED         0       /* Offset of Red in an RGB scanline element */
316#define RGB_GREEN       1       /* Offset of Green */
317#define RGB_BLUE        2       /* Offset of Blue */
318#define RGB_PIXELSIZE   3       /* JSAMPLEs per RGB scanline element */
319
320
321/* Definitions for speed-related optimizations. */
322
323
324/* If your compiler supports inline functions, define INLINE
325 * as the inline keyword; otherwise define it as empty.
326 */
327
328#ifndef INLINE
329#ifdef __GNUC__                 /* for instance, GNU C knows about inline */
330#define INLINE __inline__
331#endif
332#ifndef INLINE
333#define INLINE                  /* default is to define it as empty */
334#endif
335#endif
336
337
338/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
339 * two 16-bit shorts is faster than multiplying two ints.  Define MULTIPLIER
340 * as short on such a machine.  MULTIPLIER must be at least 16 bits wide.
341 */
342
343#ifndef MULTIPLIER
344#define MULTIPLIER  int         /* type for fastest integer multiply */
345#endif
346
347
348/* FAST_FLOAT should be either float or double, whichever is done faster
349 * by your compiler.  (Note that this type is only used in the floating point
350 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
351 * Typically, float is faster in ANSI C compilers, while double is faster in
352 * pre-ANSI compilers (because they insist on converting to double anyway).
353 * The code below therefore chooses float if we have ANSI-style prototypes.
354 */
355
356#ifndef FAST_FLOAT
357#ifdef HAVE_PROTOTYPES
358#define FAST_FLOAT  float
359#else
360#define FAST_FLOAT  double
361#endif
362#endif
363
364#endif /* JPEG_INTERNAL_OPTIONS */
Note: See TracBrowser for help on using the repository browser.