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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  * libjpeg-turbo Modifications:
8  * Copyright (C) 2009, 2011, 2014-2015, D. R. Commander.
9  * For conditions of distribution and use, see the accompanying README file.
10  *
11  * This file contains additional configuration options that customize the
12  * JPEG software for special applications or support machine-dependent
13  * optimizations.  Most users will not need to touch this file.
14  */
15 
16 
17 /*
18  * Maximum number of components (color channels) allowed in JPEG image.
19  * To meet the letter of the JPEG spec, set this to 255.  However, darn
20  * few applications need more than 4 channels (maybe 5 for CMYK + alpha
21  * mask).  We recommend 10 as a reasonable compromise; use 4 if you are
22  * really short on memory.  (Each allowed component costs a hundred or so
23  * bytes of storage, whether actually used in an image or not.)
24  */
25 
26 #define MAX_COMPONENTS  10      /* maximum number of image components */
27 
28 
29 /*
30  * Basic data types.
31  * You may need to change these if you have a machine with unusual data
32  * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
33  * or "long" not 32 bits.  We don't care whether "int" is 16 or 32 bits,
34  * but it had better be at least 16.
35  */
36 
37 /* Representation of a single sample (pixel element value).
38  * We frequently allocate large arrays of these, so it's important to keep
39  * them small.  But if you have memory to burn and access to char or short
40  * arrays is very slow on your hardware, you might want to change these.
41  */
42 
43 #if BITS_IN_JSAMPLE == 8
44 /* JSAMPLE should be the smallest type that will hold the values 0..255.
45  * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
46  */
47 
48 #ifdef HAVE_UNSIGNED_CHAR
49 
50 typedef unsigned char JSAMPLE;
51 #define GETJSAMPLE(value)  ((int) (value))
52 
53 #else /* not HAVE_UNSIGNED_CHAR */
54 
55 typedef char JSAMPLE;
56 #ifdef __CHAR_UNSIGNED__
57 #define GETJSAMPLE(value)  ((int) (value))
58 #else
59 #define GETJSAMPLE(value)  ((int) (value) & 0xFF)
60 #endif /* __CHAR_UNSIGNED__ */
61 
62 #endif /* HAVE_UNSIGNED_CHAR */
63 
64 #define MAXJSAMPLE      255
65 #define CENTERJSAMPLE   128
66 
67 #endif /* BITS_IN_JSAMPLE == 8 */
68 
69 
70 #if BITS_IN_JSAMPLE == 12
71 /* JSAMPLE should be the smallest type that will hold the values 0..4095.
72  * On nearly all machines "short" will do nicely.
73  */
74 
75 typedef short JSAMPLE;
76 #define GETJSAMPLE(value)  ((int) (value))
77 
78 #define MAXJSAMPLE      4095
79 #define CENTERJSAMPLE   2048
80 
81 #endif /* BITS_IN_JSAMPLE == 12 */
82 
83 
84 /* Representation of a DCT frequency coefficient.
85  * This should be a signed value of at least 16 bits; "short" is usually OK.
86  * Again, we allocate large arrays of these, but you can change to int
87  * if you have memory to burn and "short" is really slow.
88  */
89 
90 typedef short JCOEF;
91 
92 
93 /* Compressed datastreams are represented as arrays of JOCTET.
94  * These must be EXACTLY 8 bits wide, at least once they are written to
95  * external storage.  Note that when using the stdio data source/destination
96  * managers, this is also the data type passed to fread/fwrite.
97  */
98 
99 #ifdef HAVE_UNSIGNED_CHAR
100 
101 typedef unsigned char JOCTET;
102 #define GETJOCTET(value)  (value)
103 
104 #else /* not HAVE_UNSIGNED_CHAR */
105 
106 typedef char JOCTET;
107 #ifdef __CHAR_UNSIGNED__
108 #define GETJOCTET(value)  (value)
109 #else
110 #define GETJOCTET(value)  ((value) & 0xFF)
111 #endif /* __CHAR_UNSIGNED__ */
112 
113 #endif /* HAVE_UNSIGNED_CHAR */
114 
115 
116 /* These typedefs are used for various table entries and so forth.
117  * They must be at least as wide as specified; but making them too big
118  * won't cost a huge amount of memory, so we don't provide special
119  * extraction code like we did for JSAMPLE.  (In other words, these
120  * typedefs live at a different point on the speed/space tradeoff curve.)
121  */
122 
123 /* UINT8 must hold at least the values 0..255. */
124 
125 #ifdef HAVE_UNSIGNED_CHAR
126 typedef unsigned char UINT8;
127 #else /* not HAVE_UNSIGNED_CHAR */
128 #ifdef __CHAR_UNSIGNED__
129 typedef char UINT8;
130 #else /* not __CHAR_UNSIGNED__ */
131 typedef short UINT8;
132 #endif /* __CHAR_UNSIGNED__ */
133 #endif /* HAVE_UNSIGNED_CHAR */
134 
135 /* UINT16 must hold at least the values 0..65535. */
136 
137 #ifdef HAVE_UNSIGNED_SHORT
138 typedef unsigned short UINT16;
139 #else /* not HAVE_UNSIGNED_SHORT */
140 typedef unsigned int UINT16;
141 #endif /* HAVE_UNSIGNED_SHORT */
142 
143 /* INT16 must hold at least the values -32768..32767. */
144 
145 #ifndef XMD_H                   /* X11/xmd.h correctly defines INT16 */
146 typedef short INT16;
147 #endif
148 
149 /* INT32 must hold at least signed 32-bit values. */
150 
151 #ifndef XMD_H                   /* X11/xmd.h correctly defines INT32 */
152 #ifndef _BASETSD_H_		/* Microsoft defines it in basetsd.h */
153 #ifndef _BASETSD_H		/* MinGW is slightly different */
154 #ifndef QGLOBAL_H		/* Qt defines it in qglobal.h */
155 #define __INT32_IS_ACTUALLY_LONG
156 typedef long INT32;
157 #endif
158 #endif
159 #endif
160 #endif
161 
162 /* Datatype used for image dimensions.  The JPEG standard only supports
163  * images up to 64K*64K due to 16-bit fields in SOF markers.  Therefore
164  * "unsigned int" is sufficient on all machines.  However, if you need to
165  * handle larger images and you don't mind deviating from the spec, you
166  * can change this datatype.  (Note that changing this datatype will
167  * potentially require modifying the SIMD code.  The x86-64 SIMD extensions,
168  * in particular, assume a 32-bit JDIMENSION.)
169  */
170 
171 typedef 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 /* Originally, this macro was used as a way of defining function prototypes
194  * for both modern compilers as well as older compilers that did not support
195  * prototype parameters.  libjpeg-turbo has never supported these older,
196  * non-ANSI compilers, but the macro is still included because there is some
197  * software out there that uses it.
198  */
199 
200 #define JMETHOD(type,methodname,arglist)  type (*methodname) arglist
201 
202 
203 /* libjpeg-turbo no longer supports platforms that have far symbols (MS-DOS),
204  * but again, some software relies on this macro.
205  */
206 
207 #undef FAR
208 #define FAR
209 
210 
211 /*
212  * On a few systems, type boolean and/or its values FALSE, TRUE may appear
213  * in standard header files.  Or you may have conflicts with application-
214  * specific header files that you want to include together with these files.
215  * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
216  */
217 
218 #ifndef HAVE_BOOLEAN
219 typedef int boolean;
220 #endif
221 #ifndef FALSE                   /* in case these macros already exist */
222 #define FALSE   0               /* values of boolean */
223 #endif
224 #ifndef TRUE
225 #define TRUE    1
226 #endif
227 
228 
229 /*
230  * The remaining options affect code selection within the JPEG library,
231  * but they don't need to be visible to most applications using the library.
232  * To minimize application namespace pollution, the symbols won't be
233  * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
234  */
235 
236 #ifdef JPEG_INTERNALS
237 #define JPEG_INTERNAL_OPTIONS
238 #endif
239 
240 #ifdef JPEG_INTERNAL_OPTIONS
241 
242 
243 /*
244  * These defines indicate whether to include various optional functions.
245  * Undefining some of these symbols will produce a smaller but less capable
246  * library.  Note that you can leave certain source files out of the
247  * compilation/linking process if you've #undef'd the corresponding symbols.
248  * (You may HAVE to do that if your compiler doesn't like null source files.)
249  */
250 
251 /* Capability options common to encoder and decoder: */
252 
253 #define DCT_ISLOW_SUPPORTED     /* slow but accurate integer algorithm */
254 #define DCT_IFAST_SUPPORTED     /* faster, less accurate integer method */
255 #define DCT_FLOAT_SUPPORTED     /* floating-point: accurate, fast on fast HW */
256 
257 /* Encoder capability options: */
258 
259 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
260 #define C_PROGRESSIVE_SUPPORTED     /* Progressive JPEG? (Requires MULTISCAN)*/
261 #define ENTROPY_OPT_SUPPORTED       /* Optimization of entropy coding parms? */
262 /* Note: if you selected 12-bit data precision, it is dangerous to turn off
263  * ENTROPY_OPT_SUPPORTED.  The standard Huffman tables are only good for 8-bit
264  * precision, so jchuff.c normally uses entropy optimization to compute
265  * usable tables for higher precision.  If you don't want to do optimization,
266  * you'll have to supply different default Huffman tables.
267  * The exact same statements apply for progressive JPEG: the default tables
268  * don't work for progressive mode.  (This may get fixed, however.)
269  */
270 #define INPUT_SMOOTHING_SUPPORTED   /* Input image smoothing option? */
271 
272 /* Decoder capability options: */
273 
274 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
275 #define D_PROGRESSIVE_SUPPORTED     /* Progressive JPEG? (Requires MULTISCAN)*/
276 #define SAVE_MARKERS_SUPPORTED      /* jpeg_save_markers() needed? */
277 #define BLOCK_SMOOTHING_SUPPORTED   /* Block smoothing? (Progressive only) */
278 #define IDCT_SCALING_SUPPORTED      /* Output rescaling via IDCT? */
279 #undef  UPSAMPLE_SCALING_SUPPORTED  /* Output rescaling at upsample stage? */
280 #define UPSAMPLE_MERGING_SUPPORTED  /* Fast path for sloppy upsampling? */
281 #define QUANT_1PASS_SUPPORTED       /* 1-pass color quantization? */
282 #define QUANT_2PASS_SUPPORTED       /* 2-pass color quantization? */
283 
284 /* more capability options later, no doubt */
285 
286 
287 /*
288  * The RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros are a vestigial
289  * feature of libjpeg.  The idea was that, if an application developer needed
290  * to compress from/decompress to a BGR/BGRX/RGBX/XBGR/XRGB buffer, they could
291  * change these macros, rebuild libjpeg, and link their application statically
292  * with it.  In reality, few people ever did this, because there were some
293  * severe restrictions involved (cjpeg and djpeg no longer worked properly,
294  * compressing/decompressing RGB JPEGs no longer worked properly, and the color
295  * quantizer wouldn't work with pixel sizes other than 3.)  Further, since all
296  * of the O/S-supplied versions of libjpeg were built with the default values
297  * of RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE, many applications have
298  * come to regard these values as immutable.
299  *
300  * The libjpeg-turbo colorspace extensions provide a much cleaner way of
301  * compressing from/decompressing to buffers with arbitrary component orders
302  * and pixel sizes.  Thus, we do not support changing the values of RGB_RED,
303  * RGB_GREEN, RGB_BLUE, or RGB_PIXELSIZE.  In addition to the restrictions
304  * listed above, changing these values will also break the SIMD extensions and
305  * the regression tests.
306  */
307 
308 #define RGB_RED         0       /* Offset of Red in an RGB scanline element */
309 #define RGB_GREEN       1       /* Offset of Green */
310 #define RGB_BLUE        2       /* Offset of Blue */
311 #define RGB_PIXELSIZE   3       /* JSAMPLEs per RGB scanline element */
312 
313 #define JPEG_NUMCS 17
314 
315 #define EXT_RGB_RED        0
316 #define EXT_RGB_GREEN      1
317 #define EXT_RGB_BLUE       2
318 #define EXT_RGB_PIXELSIZE  3
319 
320 #define EXT_RGBX_RED       0
321 #define EXT_RGBX_GREEN     1
322 #define EXT_RGBX_BLUE      2
323 #define EXT_RGBX_PIXELSIZE 4
324 
325 #define EXT_BGR_RED        2
326 #define EXT_BGR_GREEN      1
327 #define EXT_BGR_BLUE       0
328 #define EXT_BGR_PIXELSIZE  3
329 
330 #define EXT_BGRX_RED       2
331 #define EXT_BGRX_GREEN     1
332 #define EXT_BGRX_BLUE      0
333 #define EXT_BGRX_PIXELSIZE 4
334 
335 #define EXT_XBGR_RED       3
336 #define EXT_XBGR_GREEN     2
337 #define EXT_XBGR_BLUE      1
338 #define EXT_XBGR_PIXELSIZE 4
339 
340 #define EXT_XRGB_RED       1
341 #define EXT_XRGB_GREEN     2
342 #define EXT_XRGB_BLUE      3
343 #define EXT_XRGB_PIXELSIZE 4
344 
345 static const int rgb_red[JPEG_NUMCS] = {
346   -1, -1, RGB_RED, -1, -1, -1, EXT_RGB_RED, EXT_RGBX_RED,
347   EXT_BGR_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED,
348   EXT_RGBX_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED,
349   -1
350 };
351 
352 static const int rgb_green[JPEG_NUMCS] = {
353   -1, -1, RGB_GREEN, -1, -1, -1, EXT_RGB_GREEN, EXT_RGBX_GREEN,
354   EXT_BGR_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN,
355   EXT_RGBX_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN,
356   -1
357 };
358 
359 static const int rgb_blue[JPEG_NUMCS] = {
360   -1, -1, RGB_BLUE, -1, -1, -1, EXT_RGB_BLUE, EXT_RGBX_BLUE,
361   EXT_BGR_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE,
362   EXT_RGBX_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE,
363   -1
364 };
365 
366 static const int rgb_pixelsize[JPEG_NUMCS] = {
367   -1, -1, RGB_PIXELSIZE, -1, -1, -1, EXT_RGB_PIXELSIZE, EXT_RGBX_PIXELSIZE,
368   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,
370   -1
371 };
372 
373 /* Definitions for speed-related optimizations. */
374 
375 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
376  * two 16-bit shorts is faster than multiplying two ints.  Define MULTIPLIER
377  * as short on such a machine.  MULTIPLIER must be at least 16 bits wide.
378  */
379 
380 #ifndef MULTIPLIER
381 #ifndef WITH_SIMD
382 #define MULTIPLIER  int         /* type for fastest integer multiply */
383 #else
384 #define MULTIPLIER short  /* prefer 16-bit with SIMD for parellelism */
385 #endif
386 #endif
387 
388 
389 /* FAST_FLOAT should be either float or double, whichever is done faster
390  * by your compiler.  (Note that this type is only used in the floating point
391  * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
392  */
393 
394 #ifndef FAST_FLOAT
395 #define FAST_FLOAT  float
396 #endif
397 
398 #endif /* JPEG_INTERNAL_OPTIONS */
399