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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, 2018, D. R. Commander.
9  * For conditions of distribution and use, see the accompanying README.ijg
10  * file.
11  *
12  * This file contains additional configuration options that customize the
13  * JPEG software for special applications or support machine-dependent
14  * optimizations.  Most users will not need to touch this file.
15  */
16 
17 
18 /*
19  * Maximum number of components (color channels) allowed in JPEG image.
20  * To meet the letter of Rec. ITU-T T.81 | ISO/IEC 10918-1, set this to 255.
21  * However, darn few applications need more than 4 channels (maybe 5 for CMYK +
22  * alpha mask).  We recommend 10 as a reasonable compromise; use 4 if you are
23  * really short on memory.  (Each allowed component costs a hundred or so
24  * bytes of storage, whether actually used in an image or not.)
25  */
26 
27 #define MAX_COMPONENTS  10      /* maximum number of image components */
28 
29 
30 /*
31  * Basic data types.
32  * You may need to change these if you have a machine with unusual data
33  * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
34  * or "long" not 32 bits.  We don't care whether "int" is 16 or 32 bits,
35  * but it had better be at least 16.
36  */
37 
38 /* Representation of a single sample (pixel element value).
39  * We frequently allocate large arrays of these, so it's important to keep
40  * them small.  But if you have memory to burn and access to char or short
41  * arrays is very slow on your hardware, you might want to change these.
42  */
43 
44 #if BITS_IN_JSAMPLE == 8
45 /* JSAMPLE should be the smallest type that will hold the values 0..255.
46  * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
47  */
48 
49 #ifdef HAVE_UNSIGNED_CHAR
50 
51 typedef unsigned char JSAMPLE;
52 #define GETJSAMPLE(value)  ((int)(value))
53 
54 #else /* not HAVE_UNSIGNED_CHAR */
55 
56 typedef char JSAMPLE;
57 #ifdef __CHAR_UNSIGNED__
58 #define GETJSAMPLE(value)  ((int)(value))
59 #else
60 #define GETJSAMPLE(value)  ((int)(value) & 0xFF)
61 #endif /* __CHAR_UNSIGNED__ */
62 
63 #endif /* HAVE_UNSIGNED_CHAR */
64 
65 #define MAXJSAMPLE      255
66 #define CENTERJSAMPLE   128
67 
68 #endif /* BITS_IN_JSAMPLE == 8 */
69 
70 
71 #if BITS_IN_JSAMPLE == 12
72 /* JSAMPLE should be the smallest type that will hold the values 0..4095.
73  * On nearly all machines "short" will do nicely.
74  */
75 
76 typedef short JSAMPLE;
77 #define GETJSAMPLE(value)  ((int)(value))
78 
79 #define MAXJSAMPLE      4095
80 #define CENTERJSAMPLE   2048
81 
82 #endif /* BITS_IN_JSAMPLE == 12 */
83 
84 
85 /* Representation of a DCT frequency coefficient.
86  * This should be a signed value of at least 16 bits; "short" is usually OK.
87  * Again, we allocate large arrays of these, but you can change to int
88  * if you have memory to burn and "short" is really slow.
89  */
90 
91 typedef short JCOEF;
92 
93 
94 /* Compressed datastreams are represented as arrays of JOCTET.
95  * These must be EXACTLY 8 bits wide, at least once they are written to
96  * external storage.  Note that when using the stdio data source/destination
97  * managers, this is also the data type passed to fread/fwrite.
98  */
99 
100 #ifdef HAVE_UNSIGNED_CHAR
101 
102 typedef unsigned char JOCTET;
103 #define GETJOCTET(value)  (value)
104 
105 #else /* not HAVE_UNSIGNED_CHAR */
106 
107 typedef char JOCTET;
108 #ifdef __CHAR_UNSIGNED__
109 #define GETJOCTET(value)  (value)
110 #else
111 #define GETJOCTET(value)  ((value) & 0xFF)
112 #endif /* __CHAR_UNSIGNED__ */
113 
114 #endif /* HAVE_UNSIGNED_CHAR */
115 
116 
117 /* These typedefs are used for various table entries and so forth.
118  * They must be at least as wide as specified; but making them too big
119  * won't cost a huge amount of memory, so we don't provide special
120  * extraction code like we did for JSAMPLE.  (In other words, these
121  * typedefs live at a different point on the speed/space tradeoff curve.)
122  */
123 
124 /* UINT8 must hold at least the values 0..255. */
125 
126 #ifdef HAVE_UNSIGNED_CHAR
127 typedef unsigned char UINT8;
128 #else /* not HAVE_UNSIGNED_CHAR */
129 #ifdef __CHAR_UNSIGNED__
130 typedef char UINT8;
131 #else /* not __CHAR_UNSIGNED__ */
132 typedef short UINT8;
133 #endif /* __CHAR_UNSIGNED__ */
134 #endif /* HAVE_UNSIGNED_CHAR */
135 
136 /* UINT16 must hold at least the values 0..65535. */
137 
138 #ifdef HAVE_UNSIGNED_SHORT
139 typedef unsigned short UINT16;
140 #else /* not HAVE_UNSIGNED_SHORT */
141 typedef unsigned int UINT16;
142 #endif /* HAVE_UNSIGNED_SHORT */
143 
144 /* INT16 must hold at least the values -32768..32767. */
145 
146 #ifndef XMD_H                   /* X11/xmd.h correctly defines INT16 */
147 typedef short INT16;
148 #endif
149 
150 /* INT32 must hold at least signed 32-bit values.
151  *
152  * NOTE: The INT32 typedef dates back to libjpeg v5 (1994.)  Integers were
153  * sometimes 16-bit back then (MS-DOS), which is why INT32 is typedef'd to
154  * long.  It also wasn't common (or at least as common) in 1994 for INT32 to be
155  * defined by platform headers.  Since then, however, INT32 is defined in
156  * several other common places:
157  *
158  * Xmd.h (X11 header) typedefs INT32 to int on 64-bit platforms and long on
159  * 32-bit platforms (i.e always a 32-bit signed type.)
160  *
161  * basetsd.h (Win32 header) typedefs INT32 to int (always a 32-bit signed type
162  * on modern platforms.)
163  *
164  * qglobal.h (Qt header) typedefs INT32 to int (always a 32-bit signed type on
165  * modern platforms.)
166  *
167  * This is a recipe for conflict, since "long" and "int" aren't always
168  * compatible types.  Since the definition of INT32 has technically been part
169  * of the libjpeg API for more than 20 years, we can't remove it, but we do not
170  * use it internally any longer.  We instead define a separate type (JLONG)
171  * for internal use, which ensures that internal behavior will always be the
172  * same regardless of any external headers that may be included.
173  */
174 
175 #ifndef XMD_H                   /* X11/xmd.h correctly defines INT32 */
176 #ifndef _BASETSD_H_             /* Microsoft defines it in basetsd.h */
177 #ifndef _BASETSD_H              /* MinGW is slightly different */
178 #ifndef QGLOBAL_H               /* Qt defines it in qglobal.h */
179 typedef long INT32;
180 #endif
181 #endif
182 #endif
183 #endif
184 
185 /* Datatype used for image dimensions.  The JPEG standard only supports
186  * images up to 64K*64K due to 16-bit fields in SOF markers.  Therefore
187  * "unsigned int" is sufficient on all machines.  However, if you need to
188  * handle larger images and you don't mind deviating from the spec, you
189  * can change this datatype.  (Note that changing this datatype will
190  * potentially require modifying the SIMD code.  The x86-64 SIMD extensions,
191  * in particular, assume a 32-bit JDIMENSION.)
192  */
193 
194 typedef unsigned int JDIMENSION;
195 
196 #define JPEG_MAX_DIMENSION  65500L  /* a tad under 64K to prevent overflows */
197 
198 
199 /* These macros are used in all function definitions and extern declarations.
200  * You could modify them if you need to change function linkage conventions;
201  * in particular, you'll need to do that to make the library a Windows DLL.
202  * Another application is to make all functions global for use with debuggers
203  * or code profilers that require it.
204  */
205 
206 /* a function called through method pointers: */
207 #define METHODDEF(type)         static type
208 /* a function used only in its module: */
209 #define LOCAL(type)             static type
210 /* a function referenced thru EXTERNs: */
211 #define GLOBAL(type)            type
212 /* a reference to a GLOBAL function: */
213 #define EXTERN(type)            extern type
214 
215 
216 /* Originally, this macro was used as a way of defining function prototypes
217  * for both modern compilers as well as older compilers that did not support
218  * prototype parameters.  libjpeg-turbo has never supported these older,
219  * non-ANSI compilers, but the macro is still included because there is some
220  * software out there that uses it.
221  */
222 
223 #define JMETHOD(type, methodname, arglist)  type (*methodname) arglist
224 
225 
226 /* libjpeg-turbo no longer supports platforms that have far symbols (MS-DOS),
227  * but again, some software relies on this macro.
228  */
229 
230 #undef FAR
231 #define FAR
232 
233 
234 /*
235  * On a few systems, type boolean and/or its values FALSE, TRUE may appear
236  * in standard header files.  Or you may have conflicts with application-
237  * specific header files that you want to include together with these files.
238  * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
239  */
240 
241 #ifndef HAVE_BOOLEAN
242 typedef int boolean;
243 #endif
244 #ifndef FALSE                   /* in case these macros already exist */
245 #define FALSE   0               /* values of boolean */
246 #endif
247 #ifndef TRUE
248 #define TRUE    1
249 #endif
250 
251 
252 /*
253  * The remaining options affect code selection within the JPEG library,
254  * but they don't need to be visible to most applications using the library.
255  * To minimize application namespace pollution, the symbols won't be
256  * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
257  */
258 
259 #ifdef JPEG_INTERNALS
260 #define JPEG_INTERNAL_OPTIONS
261 #endif
262 
263 #ifdef JPEG_INTERNAL_OPTIONS
264 
265 
266 /*
267  * These defines indicate whether to include various optional functions.
268  * Undefining some of these symbols will produce a smaller but less capable
269  * library.  Note that you can leave certain source files out of the
270  * compilation/linking process if you've #undef'd the corresponding symbols.
271  * (You may HAVE to do that if your compiler doesn't like null source files.)
272  */
273 
274 /* Capability options common to encoder and decoder: */
275 
276 #define DCT_ISLOW_SUPPORTED     /* slow but accurate integer algorithm */
277 #define DCT_IFAST_SUPPORTED     /* faster, less accurate integer method */
278 #define DCT_FLOAT_SUPPORTED     /* floating-point: accurate, fast on fast HW */
279 
280 /* Encoder capability options: */
281 
282 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
283 #define C_PROGRESSIVE_SUPPORTED     /* Progressive JPEG? (Requires MULTISCAN)*/
284 #define ENTROPY_OPT_SUPPORTED       /* Optimization of entropy coding parms? */
285 /* Note: if you selected 12-bit data precision, it is dangerous to turn off
286  * ENTROPY_OPT_SUPPORTED.  The standard Huffman tables are only good for 8-bit
287  * precision, so jchuff.c normally uses entropy optimization to compute
288  * usable tables for higher precision.  If you don't want to do optimization,
289  * you'll have to supply different default Huffman tables.
290  * The exact same statements apply for progressive JPEG: the default tables
291  * don't work for progressive mode.  (This may get fixed, however.)
292  */
293 #define INPUT_SMOOTHING_SUPPORTED   /* Input image smoothing option? */
294 
295 /* Decoder capability options: */
296 
297 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
298 #define D_PROGRESSIVE_SUPPORTED     /* Progressive JPEG? (Requires MULTISCAN)*/
299 #define SAVE_MARKERS_SUPPORTED      /* jpeg_save_markers() needed? */
300 #define BLOCK_SMOOTHING_SUPPORTED   /* Block smoothing? (Progressive only) */
301 #define IDCT_SCALING_SUPPORTED      /* Output rescaling via IDCT? */
302 #undef  UPSAMPLE_SCALING_SUPPORTED  /* Output rescaling at upsample stage? */
303 #define UPSAMPLE_MERGING_SUPPORTED  /* Fast path for sloppy upsampling? */
304 #define QUANT_1PASS_SUPPORTED       /* 1-pass color quantization? */
305 #define QUANT_2PASS_SUPPORTED       /* 2-pass color quantization? */
306 
307 /* more capability options later, no doubt */
308 
309 
310 /*
311  * The RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros are a vestigial
312  * feature of libjpeg.  The idea was that, if an application developer needed
313  * to compress from/decompress to a BGR/BGRX/RGBX/XBGR/XRGB buffer, they could
314  * change these macros, rebuild libjpeg, and link their application statically
315  * with it.  In reality, few people ever did this, because there were some
316  * severe restrictions involved (cjpeg and djpeg no longer worked properly,
317  * compressing/decompressing RGB JPEGs no longer worked properly, and the color
318  * quantizer wouldn't work with pixel sizes other than 3.)  Furthermore, since
319  * all of the O/S-supplied versions of libjpeg were built with the default
320  * values of RGB_RED, RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE, many applications
321  * have come to regard these values as immutable.
322  *
323  * The libjpeg-turbo colorspace extensions provide a much cleaner way of
324  * compressing from/decompressing to buffers with arbitrary component orders
325  * and pixel sizes.  Thus, we do not support changing the values of RGB_RED,
326  * RGB_GREEN, RGB_BLUE, or RGB_PIXELSIZE.  In addition to the restrictions
327  * listed above, changing these values will also break the SIMD extensions and
328  * the regression tests.
329  */
330 
331 #define RGB_RED         0       /* Offset of Red in an RGB scanline element */
332 #define RGB_GREEN       1       /* Offset of Green */
333 #define RGB_BLUE        2       /* Offset of Blue */
334 #define RGB_PIXELSIZE   3       /* JSAMPLEs per RGB scanline element */
335 
336 #define JPEG_NUMCS  17
337 
338 #define EXT_RGB_RED         0
339 #define EXT_RGB_GREEN       1
340 #define EXT_RGB_BLUE        2
341 #define EXT_RGB_PIXELSIZE   3
342 
343 #define EXT_RGBX_RED        0
344 #define EXT_RGBX_GREEN      1
345 #define EXT_RGBX_BLUE       2
346 #define EXT_RGBX_PIXELSIZE  4
347 
348 #define EXT_BGR_RED         2
349 #define EXT_BGR_GREEN       1
350 #define EXT_BGR_BLUE        0
351 #define EXT_BGR_PIXELSIZE   3
352 
353 #define EXT_BGRX_RED        2
354 #define EXT_BGRX_GREEN      1
355 #define EXT_BGRX_BLUE       0
356 #define EXT_BGRX_PIXELSIZE  4
357 
358 #define EXT_XBGR_RED        3
359 #define EXT_XBGR_GREEN      2
360 #define EXT_XBGR_BLUE       1
361 #define EXT_XBGR_PIXELSIZE  4
362 
363 #define EXT_XRGB_RED        1
364 #define EXT_XRGB_GREEN      2
365 #define EXT_XRGB_BLUE       3
366 #define EXT_XRGB_PIXELSIZE  4
367 
368 static const int rgb_red[JPEG_NUMCS] = {
369   -1, -1, RGB_RED, -1, -1, -1, EXT_RGB_RED, EXT_RGBX_RED,
370   EXT_BGR_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED,
371   EXT_RGBX_RED, EXT_BGRX_RED, EXT_XBGR_RED, EXT_XRGB_RED,
372   -1
373 };
374 
375 static const int rgb_green[JPEG_NUMCS] = {
376   -1, -1, RGB_GREEN, -1, -1, -1, EXT_RGB_GREEN, EXT_RGBX_GREEN,
377   EXT_BGR_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN,
378   EXT_RGBX_GREEN, EXT_BGRX_GREEN, EXT_XBGR_GREEN, EXT_XRGB_GREEN,
379   -1
380 };
381 
382 static const int rgb_blue[JPEG_NUMCS] = {
383   -1, -1, RGB_BLUE, -1, -1, -1, EXT_RGB_BLUE, EXT_RGBX_BLUE,
384   EXT_BGR_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE,
385   EXT_RGBX_BLUE, EXT_BGRX_BLUE, EXT_XBGR_BLUE, EXT_XRGB_BLUE,
386   -1
387 };
388 
389 static const int rgb_pixelsize[JPEG_NUMCS] = {
390   -1, -1, RGB_PIXELSIZE, -1, -1, -1, EXT_RGB_PIXELSIZE, EXT_RGBX_PIXELSIZE,
391   EXT_BGR_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE,
392   EXT_RGBX_PIXELSIZE, EXT_BGRX_PIXELSIZE, EXT_XBGR_PIXELSIZE, EXT_XRGB_PIXELSIZE,
393   -1
394 };
395 
396 /* Definitions for speed-related optimizations. */
397 
398 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
399  * two 16-bit shorts is faster than multiplying two ints.  Define MULTIPLIER
400  * as short on such a machine.  MULTIPLIER must be at least 16 bits wide.
401  */
402 
403 #ifndef MULTIPLIER
404 #ifndef WITH_SIMD
405 #define MULTIPLIER  int         /* type for fastest integer multiply */
406 #else
407 #define MULTIPLIER  short       /* prefer 16-bit with SIMD for parellelism */
408 #endif
409 #endif
410 
411 
412 /* FAST_FLOAT should be either float or double, whichever is done faster
413  * by your compiler.  (Note that this type is only used in the floating point
414  * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
415  */
416 
417 #ifndef FAST_FLOAT
418 #define FAST_FLOAT  float
419 #endif
420 
421 #endif /* JPEG_INTERNAL_OPTIONS */
422