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Thomas G. Lane36a4ccc1994-09-24 00:00:00 +00001/*
2 * jmorecfg.h
3 *
Thomas G. Lane5ead57a1998-03-27 00:00:00 +00004 * Copyright (C) 1991-1997, Thomas G. Lane.
DRC67ce3b22011-12-19 02:21:03 +00005 * Copyright (C) 2009, 2011, D. R. Commander.
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +00006 * 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 * 12 for 12-bit sample values
19 * Only 8 and 12 are legal data precisions for lossy JPEG according to the
20 * JPEG standard, and the IJG code does not support anything else!
21 * We do not support run-time selection of data precision, sorry.
22 */
23
24#define BITS_IN_JSAMPLE 8 /* use 8 or 12 */
25
26
27/*
28 * Maximum number of components (color channels) allowed in JPEG image.
29 * To meet the letter of the JPEG spec, set this to 255. However, darn
30 * few applications need more than 4 channels (maybe 5 for CMYK + alpha
31 * mask). We recommend 10 as a reasonable compromise; use 4 if you are
32 * really short on memory. (Each allowed component costs a hundred or so
33 * bytes of storage, whether actually used in an image or not.)
34 */
35
36#define MAX_COMPONENTS 10 /* maximum number of image components */
37
38
39/*
40 * Basic data types.
41 * You may need to change these if you have a machine with unusual data
42 * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
43 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits,
44 * but it had better be at least 16.
45 */
46
47/* Representation of a single sample (pixel element value).
48 * We frequently allocate large arrays of these, so it's important to keep
49 * them small. But if you have memory to burn and access to char or short
50 * arrays is very slow on your hardware, you might want to change these.
51 */
52
53#if BITS_IN_JSAMPLE == 8
54/* JSAMPLE should be the smallest type that will hold the values 0..255.
55 * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
56 */
57
58#ifdef HAVE_UNSIGNED_CHAR
59
60typedef unsigned char JSAMPLE;
61#define GETJSAMPLE(value) ((int) (value))
62
63#else /* not HAVE_UNSIGNED_CHAR */
64
65typedef char JSAMPLE;
Constantin Kaplinsky0ca44252008-09-28 05:08:48 +000066#ifdef __CHAR_UNSIGNED__
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000067#define GETJSAMPLE(value) ((int) (value))
68#else
69#define GETJSAMPLE(value) ((int) (value) & 0xFF)
Constantin Kaplinsky0ca44252008-09-28 05:08:48 +000070#endif /* __CHAR_UNSIGNED__ */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000071
72#endif /* HAVE_UNSIGNED_CHAR */
73
74#define MAXJSAMPLE 255
75#define CENTERJSAMPLE 128
76
77#endif /* BITS_IN_JSAMPLE == 8 */
78
79
80#if BITS_IN_JSAMPLE == 12
81/* JSAMPLE should be the smallest type that will hold the values 0..4095.
82 * On nearly all machines "short" will do nicely.
83 */
84
85typedef short JSAMPLE;
86#define GETJSAMPLE(value) ((int) (value))
87
88#define MAXJSAMPLE 4095
89#define CENTERJSAMPLE 2048
90
91#endif /* BITS_IN_JSAMPLE == 12 */
92
93
94/* Representation of a DCT frequency coefficient.
95 * This should be a signed value of at least 16 bits; "short" is usually OK.
96 * Again, we allocate large arrays of these, but you can change to int
97 * if you have memory to burn and "short" is really slow.
98 */
99
100typedef short JCOEF;
101
102
103/* Compressed datastreams are represented as arrays of JOCTET.
104 * These must be EXACTLY 8 bits wide, at least once they are written to
105 * external storage. Note that when using the stdio data source/destination
106 * managers, this is also the data type passed to fread/fwrite.
107 */
108
109#ifdef HAVE_UNSIGNED_CHAR
110
111typedef unsigned char JOCTET;
112#define GETJOCTET(value) (value)
113
114#else /* not HAVE_UNSIGNED_CHAR */
115
116typedef char JOCTET;
Constantin Kaplinsky0ca44252008-09-28 05:08:48 +0000117#ifdef __CHAR_UNSIGNED__
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000118#define GETJOCTET(value) (value)
119#else
120#define GETJOCTET(value) ((value) & 0xFF)
Constantin Kaplinsky0ca44252008-09-28 05:08:48 +0000121#endif /* __CHAR_UNSIGNED__ */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000122
123#endif /* HAVE_UNSIGNED_CHAR */
124
125
126/* These typedefs are used for various table entries and so forth.
127 * They must be at least as wide as specified; but making them too big
128 * won't cost a huge amount of memory, so we don't provide special
129 * extraction code like we did for JSAMPLE. (In other words, these
130 * typedefs live at a different point on the speed/space tradeoff curve.)
131 */
132
133/* UINT8 must hold at least the values 0..255. */
134
135#ifdef HAVE_UNSIGNED_CHAR
136typedef unsigned char UINT8;
137#else /* not HAVE_UNSIGNED_CHAR */
Constantin Kaplinsky0ca44252008-09-28 05:08:48 +0000138#ifdef __CHAR_UNSIGNED__
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000139typedef char UINT8;
Constantin Kaplinsky0ca44252008-09-28 05:08:48 +0000140#else /* not __CHAR_UNSIGNED__ */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000141typedef short UINT8;
Constantin Kaplinsky0ca44252008-09-28 05:08:48 +0000142#endif /* __CHAR_UNSIGNED__ */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000143#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
159/* INT32 must hold at least signed 32-bit values. */
160
161#ifndef XMD_H /* X11/xmd.h correctly defines INT32 */
162typedef long INT32;
163#endif
164
165/* Datatype used for image dimensions. The JPEG standard only supports
166 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore
167 * "unsigned int" is sufficient on all machines. However, if you need to
168 * handle larger images and you don't mind deviating from the spec, you
169 * can change this datatype.
170 */
171
172typedef unsigned int JDIMENSION;
173
174#define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */
175
176
Thomas G. Lane489583f1996-02-07 00:00:00 +0000177/* These macros are used in all function definitions and extern declarations.
178 * You could modify them if you need to change function linkage conventions;
179 * in particular, you'll need to do that to make the library a Windows DLL.
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000180 * Another application is to make all functions global for use with debuggers
181 * or code profilers that require it.
182 */
183
Thomas G. Lane489583f1996-02-07 00:00:00 +0000184/* a function called through method pointers: */
185#define METHODDEF(type) static type
186/* a function used only in its module: */
187#define LOCAL(type) static type
188/* a function referenced thru EXTERNs: */
189#define GLOBAL(type) type
190/* a reference to a GLOBAL function: */
191#define EXTERN(type) extern type
192
193
194/* This macro is used to declare a "method", that is, a function pointer.
195 * We want to supply prototype parameters if the compiler can cope.
196 * Note that the arglist parameter must be parenthesized!
197 * Again, you can customize this if you need special linkage keywords.
198 */
199
200#ifdef HAVE_PROTOTYPES
201#define JMETHOD(type,methodname,arglist) type (*methodname) arglist
202#else
203#define JMETHOD(type,methodname,arglist) type (*methodname) ()
204#endif
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000205
206
207/* Here is the pseudo-keyword for declaring pointers that must be "far"
208 * on 80x86 machines. Most of the specialized coding for 80x86 is handled
209 * by just saying "FAR *" where such a pointer is needed. In a few places
210 * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
211 */
212
213#ifdef NEED_FAR_POINTERS
214#define FAR far
215#else
216#define FAR
217#endif
218
219
220/*
221 * On a few systems, type boolean and/or its values FALSE, TRUE may appear
222 * in standard header files. Or you may have conflicts with application-
223 * specific header files that you want to include together with these files.
224 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
225 */
226
227#ifndef HAVE_BOOLEAN
228typedef int boolean;
229#endif
230#ifndef FALSE /* in case these macros already exist */
231#define FALSE 0 /* values of boolean */
232#endif
233#ifndef TRUE
234#define TRUE 1
235#endif
236
237
238/*
239 * The remaining options affect code selection within the JPEG library,
240 * but they don't need to be visible to most applications using the library.
241 * To minimize application namespace pollution, the symbols won't be
242 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
243 */
244
245#ifdef JPEG_INTERNALS
246#define JPEG_INTERNAL_OPTIONS
247#endif
248
249#ifdef JPEG_INTERNAL_OPTIONS
250
251
252/*
253 * These defines indicate whether to include various optional functions.
254 * Undefining some of these symbols will produce a smaller but less capable
255 * library. Note that you can leave certain source files out of the
256 * compilation/linking process if you've #undef'd the corresponding symbols.
257 * (You may HAVE to do that if your compiler doesn't like null source files.)
258 */
259
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000260/* Capability options common to encoder and decoder: */
261
262#define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */
263#define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */
264#define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */
265
266/* Encoder capability options: */
267
Thomas G. Lanebc79e061995-08-02 00:00:00 +0000268#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
269#define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000270#define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */
271/* Note: if you selected 12-bit data precision, it is dangerous to turn off
272 * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit
273 * precision, so jchuff.c normally uses entropy optimization to compute
274 * usable tables for higher precision. If you don't want to do optimization,
275 * you'll have to supply different default Huffman tables.
Thomas G. Lanebc79e061995-08-02 00:00:00 +0000276 * The exact same statements apply for progressive JPEG: the default tables
277 * don't work for progressive mode. (This may get fixed, however.)
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000278 */
279#define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */
280
281/* Decoder capability options: */
282
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000283#define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
Thomas G. Lanebc79e061995-08-02 00:00:00 +0000284#define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
Thomas G. Lane5ead57a1998-03-27 00:00:00 +0000285#define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */
Thomas G. Lanebc79e061995-08-02 00:00:00 +0000286#define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000287#define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */
288#undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */
289#define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */
290#define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */
291#define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */
292
293/* more capability options later, no doubt */
294
295
296/*
297 * Ordering of RGB data in scanlines passed to or from the application.
298 * If your application wants to deal with data in the order B,G,R, just
299 * change these macros. You can also deal with formats such as R,G,B,X
300 * (one extra byte per pixel) by changing RGB_PIXELSIZE. Note that changing
301 * the offsets will also change the order in which colormap data is organized.
302 * RESTRICTIONS:
303 * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
304 * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not
305 * useful if you are using JPEG color spaces other than YCbCr or grayscale.
306 * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
307 * is not 3 (they don't understand about dummy color components!). So you
308 * can't use color quantization if you change that value.
309 */
310
311#define RGB_RED 0 /* Offset of Red in an RGB scanline element */
312#define RGB_GREEN 1 /* Offset of Green */
313#define RGB_BLUE 2 /* Offset of Blue */
314#define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */
315
DRC67ce3b22011-12-19 02:21:03 +0000316#define JPEG_NUMCS 16
DRCf25c0712009-04-03 12:00:51 +0000317
DRCb4570bb2011-09-07 06:31:00 +0000318#define EXT_RGB_RED 0
319#define EXT_RGB_GREEN 1
320#define EXT_RGB_BLUE 2
321#define EXT_RGB_PIXELSIZE 3
322
323#define EXT_RGBX_RED 0
324#define EXT_RGBX_GREEN 1
325#define EXT_RGBX_BLUE 2
326#define EXT_RGBX_PIXELSIZE 4
327
328#define EXT_BGR_RED 2
329#define EXT_BGR_GREEN 1
330#define EXT_BGR_BLUE 0
331#define EXT_BGR_PIXELSIZE 3
332
333#define EXT_BGRX_RED 2
334#define EXT_BGRX_GREEN 1
335#define EXT_BGRX_BLUE 0
336#define EXT_BGRX_PIXELSIZE 4
337
338#define EXT_XBGR_RED 3
339#define EXT_XBGR_GREEN 2
340#define EXT_XBGR_BLUE 1
341#define EXT_XBGR_PIXELSIZE 4
342
343#define EXT_XRGB_RED 1
344#define EXT_XRGB_GREEN 2
345#define EXT_XRGB_BLUE 3
346#define EXT_XRGB_PIXELSIZE 4
347
DRCf25c0712009-04-03 12:00:51 +0000348static const int rgb_red[JPEG_NUMCS] = {
DRCb4570bb2011-09-07 06:31:00 +0000349 -1, -1, RGB_RED, -1, -1, -1, EXT_RGB_RED, EXT_RGBX_RED,
DRC67ce3b22011-12-19 02:21:03 +0000350 EXT_BGR_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED,
351 EXT_RGBX_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED
DRCf25c0712009-04-03 12:00:51 +0000352};
353
354static const int rgb_green[JPEG_NUMCS] = {
DRCb4570bb2011-09-07 06:31:00 +0000355 -1, -1, RGB_GREEN, -1, -1, -1, EXT_RGB_GREEN, EXT_RGBX_GREEN,
DRC67ce3b22011-12-19 02:21:03 +0000356 EXT_BGR_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN,
357 EXT_RGBX_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN
DRCf25c0712009-04-03 12:00:51 +0000358};
359
360static const int rgb_blue[JPEG_NUMCS] = {
DRCb4570bb2011-09-07 06:31:00 +0000361 -1, -1, RGB_BLUE, -1, -1, -1, EXT_RGB_BLUE, EXT_RGBX_BLUE,
DRC67ce3b22011-12-19 02:21:03 +0000362 EXT_BGR_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE,
363 EXT_RGBX_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE
DRCf25c0712009-04-03 12:00:51 +0000364};
365
366static const int rgb_pixelsize[JPEG_NUMCS] = {
DRCb4570bb2011-09-07 06:31:00 +0000367 -1, -1, RGB_PIXELSIZE, -1, -1, -1, EXT_RGB_PIXELSIZE, EXT_RGBX_PIXELSIZE,
DRC67ce3b22011-12-19 02:21:03 +0000368 EXT_BGR_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE,
369 EXT_RGBX_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE
DRCf25c0712009-04-03 12:00:51 +0000370};
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000371
372/* Definitions for speed-related optimizations. */
373
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000374/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
375 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER
376 * as short on such a machine. MULTIPLIER must be at least 16 bits wide.
377 */
378
379#ifndef MULTIPLIER
Pierre Ossman5eb84ff2009-03-09 13:25:30 +0000380#ifndef WITH_SIMD
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000381#define MULTIPLIER int /* type for fastest integer multiply */
Pierre Ossman5eb84ff2009-03-09 13:25:30 +0000382#else
383#define MULTIPLIER short /* prefer 16-bit with SIMD for parellelism */
384#endif
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000385#endif
386
387
388/* FAST_FLOAT should be either float or double, whichever is done faster
389 * by your compiler. (Note that this type is only used in the floating point
390 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
391 * Typically, float is faster in ANSI C compilers, while double is faster in
392 * pre-ANSI compilers (because they insist on converting to double anyway).
393 * The code below therefore chooses float if we have ANSI-style prototypes.
394 */
395
396#ifndef FAST_FLOAT
397#ifdef HAVE_PROTOTYPES
398#define FAST_FLOAT float
399#else
400#define FAST_FLOAT double
401#endif
402#endif
403
404#endif /* JPEG_INTERNAL_OPTIONS */