1 | |
2 | /* png.h - header file for PNG reference library |
3 | * |
4 | * libpng version 1.6.43 |
5 | * |
6 | * Copyright (c) 2018-2024 Cosmin Truta |
7 | * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson |
8 | * Copyright (c) 1996-1997 Andreas Dilger |
9 | * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
10 | * |
11 | * This code is released under the libpng license. (See LICENSE, below.) |
12 | * |
13 | * Authors and maintainers: |
14 | * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat |
15 | * libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger |
16 | * libpng versions 0.97, January 1998, through 1.6.35, July 2018: |
17 | * Glenn Randers-Pehrson |
18 | * libpng versions 1.6.36, December 2018, through 1.6.43, February 2024: |
19 | * Cosmin Truta |
20 | * See also "Contributing Authors", below. |
21 | */ |
22 | |
23 | /* |
24 | * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE |
25 | * ========================================= |
26 | * |
27 | * PNG Reference Library License version 2 |
28 | * --------------------------------------- |
29 | * |
30 | * * Copyright (c) 1995-2024 The PNG Reference Library Authors. |
31 | * * Copyright (c) 2018-2024 Cosmin Truta. |
32 | * * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson. |
33 | * * Copyright (c) 1996-1997 Andreas Dilger. |
34 | * * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
35 | * |
36 | * The software is supplied "as is", without warranty of any kind, |
37 | * express or implied, including, without limitation, the warranties |
38 | * of merchantability, fitness for a particular purpose, title, and |
39 | * non-infringement. In no event shall the Copyright owners, or |
40 | * anyone distributing the software, be liable for any damages or |
41 | * other liability, whether in contract, tort or otherwise, arising |
42 | * from, out of, or in connection with the software, or the use or |
43 | * other dealings in the software, even if advised of the possibility |
44 | * of such damage. |
45 | * |
46 | * Permission is hereby granted to use, copy, modify, and distribute |
47 | * this software, or portions hereof, for any purpose, without fee, |
48 | * subject to the following restrictions: |
49 | * |
50 | * 1. The origin of this software must not be misrepresented; you |
51 | * must not claim that you wrote the original software. If you |
52 | * use this software in a product, an acknowledgment in the product |
53 | * documentation would be appreciated, but is not required. |
54 | * |
55 | * 2. Altered source versions must be plainly marked as such, and must |
56 | * not be misrepresented as being the original software. |
57 | * |
58 | * 3. This Copyright notice may not be removed or altered from any |
59 | * source or altered source distribution. |
60 | * |
61 | * |
62 | * PNG Reference Library License version 1 (for libpng 0.5 through 1.6.35) |
63 | * ----------------------------------------------------------------------- |
64 | * |
65 | * libpng versions 1.0.7, July 1, 2000, through 1.6.35, July 15, 2018 are |
66 | * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson, are |
67 | * derived from libpng-1.0.6, and are distributed according to the same |
68 | * disclaimer and license as libpng-1.0.6 with the following individuals |
69 | * added to the list of Contributing Authors: |
70 | * |
71 | * Simon-Pierre Cadieux |
72 | * Eric S. Raymond |
73 | * Mans Rullgard |
74 | * Cosmin Truta |
75 | * Gilles Vollant |
76 | * James Yu |
77 | * Mandar Sahastrabuddhe |
78 | * Google Inc. |
79 | * Vadim Barkov |
80 | * |
81 | * and with the following additions to the disclaimer: |
82 | * |
83 | * There is no warranty against interference with your enjoyment of |
84 | * the library or against infringement. There is no warranty that our |
85 | * efforts or the library will fulfill any of your particular purposes |
86 | * or needs. This library is provided with all faults, and the entire |
87 | * risk of satisfactory quality, performance, accuracy, and effort is |
88 | * with the user. |
89 | * |
90 | * Some files in the "contrib" directory and some configure-generated |
91 | * files that are distributed with libpng have other copyright owners, and |
92 | * are released under other open source licenses. |
93 | * |
94 | * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are |
95 | * Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from |
96 | * libpng-0.96, and are distributed according to the same disclaimer and |
97 | * license as libpng-0.96, with the following individuals added to the |
98 | * list of Contributing Authors: |
99 | * |
100 | * Tom Lane |
101 | * Glenn Randers-Pehrson |
102 | * Willem van Schaik |
103 | * |
104 | * libpng versions 0.89, June 1996, through 0.96, May 1997, are |
105 | * Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88, |
106 | * and are distributed according to the same disclaimer and license as |
107 | * libpng-0.88, with the following individuals added to the list of |
108 | * Contributing Authors: |
109 | * |
110 | * John Bowler |
111 | * Kevin Bracey |
112 | * Sam Bushell |
113 | * Magnus Holmgren |
114 | * Greg Roelofs |
115 | * Tom Tanner |
116 | * |
117 | * Some files in the "scripts" directory have other copyright owners, |
118 | * but are released under this license. |
119 | * |
120 | * libpng versions 0.5, May 1995, through 0.88, January 1996, are |
121 | * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
122 | * |
123 | * For the purposes of this copyright and license, "Contributing Authors" |
124 | * is defined as the following set of individuals: |
125 | * |
126 | * Andreas Dilger |
127 | * Dave Martindale |
128 | * Guy Eric Schalnat |
129 | * Paul Schmidt |
130 | * Tim Wegner |
131 | * |
132 | * The PNG Reference Library is supplied "AS IS". The Contributing |
133 | * Authors and Group 42, Inc. disclaim all warranties, expressed or |
134 | * implied, including, without limitation, the warranties of |
135 | * merchantability and of fitness for any purpose. The Contributing |
136 | * Authors and Group 42, Inc. assume no liability for direct, indirect, |
137 | * incidental, special, exemplary, or consequential damages, which may |
138 | * result from the use of the PNG Reference Library, even if advised of |
139 | * the possibility of such damage. |
140 | * |
141 | * Permission is hereby granted to use, copy, modify, and distribute this |
142 | * source code, or portions hereof, for any purpose, without fee, subject |
143 | * to the following restrictions: |
144 | * |
145 | * 1. The origin of this source code must not be misrepresented. |
146 | * |
147 | * 2. Altered versions must be plainly marked as such and must not |
148 | * be misrepresented as being the original source. |
149 | * |
150 | * 3. This Copyright notice may not be removed or altered from any |
151 | * source or altered source distribution. |
152 | * |
153 | * The Contributing Authors and Group 42, Inc. specifically permit, |
154 | * without fee, and encourage the use of this source code as a component |
155 | * to supporting the PNG file format in commercial products. If you use |
156 | * this source code in a product, acknowledgment is not required but would |
157 | * be appreciated. |
158 | * |
159 | * END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE. |
160 | * |
161 | * TRADEMARK |
162 | * ========= |
163 | * |
164 | * The name "libpng" has not been registered by the Copyright owners |
165 | * as a trademark in any jurisdiction. However, because libpng has |
166 | * been distributed and maintained world-wide, continually since 1995, |
167 | * the Copyright owners claim "common-law trademark protection" in any |
168 | * jurisdiction where common-law trademark is recognized. |
169 | */ |
170 | |
171 | /* |
172 | * A "png_get_copyright" function is available, for convenient use in "about" |
173 | * boxes and the like: |
174 | * |
175 | * printf("%s", png_get_copyright(NULL)); |
176 | * |
177 | * Also, the PNG logo (in PNG format, of course) is supplied in the |
178 | * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). |
179 | */ |
180 | |
181 | /* |
182 | * The contributing authors would like to thank all those who helped |
183 | * with testing, bug fixes, and patience. This wouldn't have been |
184 | * possible without all of you. |
185 | * |
186 | * Thanks to Frank J. T. Wojcik for helping with the documentation. |
187 | */ |
188 | |
189 | /* Note about libpng version numbers: |
190 | * |
191 | * Due to various miscommunications, unforeseen code incompatibilities |
192 | * and occasional factors outside the authors' control, version numbering |
193 | * on the library has not always been consistent and straightforward. |
194 | * The following table summarizes matters since version 0.89c, which was |
195 | * the first widely used release: |
196 | * |
197 | * source png.h png.h shared-lib |
198 | * version string int version |
199 | * ------- ------ ----- ---------- |
200 | * 0.89c "1.0 beta 3" 0.89 89 1.0.89 |
201 | * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] |
202 | * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] |
203 | * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] |
204 | * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] |
205 | * 0.97c 0.97 97 2.0.97 |
206 | * 0.98 0.98 98 2.0.98 |
207 | * 0.99 0.99 98 2.0.99 |
208 | * 0.99a-m 0.99 99 2.0.99 |
209 | * 1.00 1.00 100 2.1.0 [100 should be 10000] |
210 | * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] |
211 | * 1.0.1 png.h string is 10001 2.1.0 |
212 | * 1.0.1a-e identical to the 10002 from here on, the shared library |
213 | * 1.0.2 source version) 10002 is 2.V where V is the source code |
214 | * 1.0.2a-b 10003 version, except as noted. |
215 | * 1.0.3 10003 |
216 | * 1.0.3a-d 10004 |
217 | * 1.0.4 10004 |
218 | * 1.0.4a-f 10005 |
219 | * 1.0.5 (+ 2 patches) 10005 |
220 | * 1.0.5a-d 10006 |
221 | * 1.0.5e-r 10100 (not source compatible) |
222 | * 1.0.5s-v 10006 (not binary compatible) |
223 | * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) |
224 | * 1.0.6d-f 10007 (still binary incompatible) |
225 | * 1.0.6g 10007 |
226 | * 1.0.6h 10007 10.6h (testing xy.z so-numbering) |
227 | * 1.0.6i 10007 10.6i |
228 | * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) |
229 | * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) |
230 | * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) |
231 | * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) |
232 | * 1.0.7 1 10007 (still compatible) |
233 | * ... |
234 | * 1.0.69 10 10069 10.so.0.69[.0] |
235 | * ... |
236 | * 1.2.59 13 10259 12.so.0.59[.0] |
237 | * ... |
238 | * 1.4.20 14 10420 14.so.0.20[.0] |
239 | * ... |
240 | * 1.5.30 15 10530 15.so.15.30[.0] |
241 | * ... |
242 | * 1.6.43 16 10643 16.so.16.43[.0] |
243 | * |
244 | * Henceforth the source version will match the shared-library major and |
245 | * minor numbers; the shared-library major version number will be used for |
246 | * changes in backward compatibility, as it is intended. |
247 | * The PNG_LIBPNG_VER macro, which is not used within libpng but is |
248 | * available for applications, is an unsigned integer of the form XYYZZ |
249 | * corresponding to the source version X.Y.Z (leading zeros in Y and Z). |
250 | * Beta versions were given the previous public release number plus a |
251 | * letter, until version 1.0.6j; from then on they were given the upcoming |
252 | * public release number plus "betaNN" or "rcNN". |
253 | * |
254 | * Binary incompatibility exists only when applications make direct access |
255 | * to the info_ptr or png_ptr members through png.h, and the compiled |
256 | * application is loaded with a different version of the library. |
257 | * |
258 | * See libpng.txt or libpng.3 for more information. The PNG specification |
259 | * is available as a W3C Recommendation and as an ISO/IEC Standard; see |
260 | * <https://www.w3.org/TR/2003/REC-PNG-20031110/> |
261 | */ |
262 | |
263 | #ifndef PNG_H |
264 | #define PNG_H |
265 | |
266 | /* This is not the place to learn how to use libpng. The file libpng-manual.txt |
267 | * describes how to use libpng, and the file example.c summarizes it |
268 | * with some code on which to build. This file is useful for looking |
269 | * at the actual function definitions and structure components. If that |
270 | * file has been stripped from your copy of libpng, you can find it at |
271 | * <http://www.libpng.org/pub/png/libpng-manual.txt> |
272 | * |
273 | * If you just need to read a PNG file and don't want to read the documentation |
274 | * skip to the end of this file and read the section entitled 'simplified API'. |
275 | */ |
276 | |
277 | /* Version information for png.h - this should match the version in png.c */ |
278 | #define PNG_LIBPNG_VER_STRING "1.6.43" |
279 | #define " libpng version " PNG_LIBPNG_VER_STRING "\n" |
280 | |
281 | /* The versions of shared library builds should stay in sync, going forward */ |
282 | #define PNG_LIBPNG_VER_SHAREDLIB 16 |
283 | #define PNG_LIBPNG_VER_SONUM PNG_LIBPNG_VER_SHAREDLIB /* [Deprecated] */ |
284 | #define PNG_LIBPNG_VER_DLLNUM PNG_LIBPNG_VER_SHAREDLIB /* [Deprecated] */ |
285 | |
286 | /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */ |
287 | #define PNG_LIBPNG_VER_MAJOR 1 |
288 | #define PNG_LIBPNG_VER_MINOR 6 |
289 | #define PNG_LIBPNG_VER_RELEASE 43 |
290 | |
291 | /* This should be zero for a public release, or non-zero for a |
292 | * development version. |
293 | */ |
294 | #define PNG_LIBPNG_VER_BUILD 0 |
295 | |
296 | /* Release Status */ |
297 | #define PNG_LIBPNG_BUILD_ALPHA 1 |
298 | #define PNG_LIBPNG_BUILD_BETA 2 |
299 | #define PNG_LIBPNG_BUILD_RC 3 |
300 | #define PNG_LIBPNG_BUILD_STABLE 4 |
301 | #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 |
302 | |
303 | /* Release-Specific Flags */ |
304 | #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with |
305 | PNG_LIBPNG_BUILD_STABLE only */ |
306 | #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with |
307 | PNG_LIBPNG_BUILD_SPECIAL */ |
308 | #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with |
309 | PNG_LIBPNG_BUILD_PRIVATE */ |
310 | |
311 | #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE |
312 | |
313 | /* Careful here. At one time, Guy wanted to use 082, but that |
314 | * would be octal. We must not include leading zeros. |
315 | * Versions 0.7 through 1.0.0 were in the range 0 to 100 here |
316 | * (only version 1.0.0 was mis-numbered 100 instead of 10000). |
317 | * From version 1.0.1 it is: |
318 | * XXYYZZ, where XX=major, YY=minor, ZZ=release |
319 | */ |
320 | #define PNG_LIBPNG_VER 10643 /* 1.6.43 */ |
321 | |
322 | /* Library configuration: these options cannot be changed after |
323 | * the library has been built. |
324 | */ |
325 | #ifndef PNGLCONF_H |
326 | /* If pnglibconf.h is missing, you can |
327 | * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h |
328 | */ |
329 | # include "pnglibconf.h" |
330 | #endif |
331 | |
332 | #ifndef PNG_VERSION_INFO_ONLY |
333 | /* Machine specific configuration. */ |
334 | # include "pngconf.h" |
335 | #endif |
336 | |
337 | /* |
338 | * Added at libpng-1.2.8 |
339 | * |
340 | * Ref MSDN: Private as priority over Special |
341 | * VS_FF_PRIVATEBUILD File *was not* built using standard release |
342 | * procedures. If this value is given, the StringFileInfo block must |
343 | * contain a PrivateBuild string. |
344 | * |
345 | * VS_FF_SPECIALBUILD File *was* built by the original company using |
346 | * standard release procedures but is a variation of the standard |
347 | * file of the same version number. If this value is given, the |
348 | * StringFileInfo block must contain a SpecialBuild string. |
349 | */ |
350 | |
351 | #ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */ |
352 | # define PNG_LIBPNG_BUILD_TYPE \ |
353 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) |
354 | #else |
355 | # ifdef PNG_LIBPNG_SPECIALBUILD |
356 | # define PNG_LIBPNG_BUILD_TYPE \ |
357 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) |
358 | # else |
359 | # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) |
360 | # endif |
361 | #endif |
362 | |
363 | #ifndef PNG_VERSION_INFO_ONLY |
364 | |
365 | /* Inhibit C++ name-mangling for libpng functions but not for system calls. */ |
366 | #ifdef __cplusplus |
367 | extern "C" { |
368 | #endif /* __cplusplus */ |
369 | |
370 | /* Version information for C files, stored in png.c. This had better match |
371 | * the version above. |
372 | */ |
373 | #define png_libpng_ver png_get_header_ver(NULL) |
374 | |
375 | /* This file is arranged in several sections: |
376 | * |
377 | * 1. [omitted] |
378 | * 2. Any configuration options that can be specified by for the application |
379 | * code when it is built. (Build time configuration is in pnglibconf.h) |
380 | * 3. Type definitions (base types are defined in pngconf.h), structure |
381 | * definitions. |
382 | * 4. Exported library functions. |
383 | * 5. Simplified API. |
384 | * 6. Implementation options. |
385 | * |
386 | * The library source code has additional files (principally pngpriv.h) that |
387 | * allow configuration of the library. |
388 | */ |
389 | |
390 | /* Section 1: [omitted] */ |
391 | |
392 | /* Section 2: run time configuration |
393 | * See pnglibconf.h for build time configuration |
394 | * |
395 | * Run time configuration allows the application to choose between |
396 | * implementations of certain arithmetic APIs. The default is set |
397 | * at build time and recorded in pnglibconf.h, but it is safe to |
398 | * override these (and only these) settings. Note that this won't |
399 | * change what the library does, only application code, and the |
400 | * settings can (and probably should) be made on a per-file basis |
401 | * by setting the #defines before including png.h |
402 | * |
403 | * Use macros to read integers from PNG data or use the exported |
404 | * functions? |
405 | * PNG_USE_READ_MACROS: use the macros (see below) Note that |
406 | * the macros evaluate their argument multiple times. |
407 | * PNG_NO_USE_READ_MACROS: call the relevant library function. |
408 | * |
409 | * Use the alternative algorithm for compositing alpha samples that |
410 | * does not use division? |
411 | * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' |
412 | * algorithm. |
413 | * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. |
414 | * |
415 | * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is |
416 | * false? |
417 | * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error |
418 | * APIs to png_warning. |
419 | * Otherwise the calls are mapped to png_error. |
420 | */ |
421 | |
422 | /* Section 3: type definitions, including structures and compile time |
423 | * constants. |
424 | * See pngconf.h for base types that vary by machine/system |
425 | */ |
426 | |
427 | /* This triggers a compiler error in png.c, if png.c and png.h |
428 | * do not agree upon the version number. |
429 | */ |
430 | typedef char* png_libpng_version_1_6_43; |
431 | |
432 | /* Basic control structions. Read libpng-manual.txt or libpng.3 for more info. |
433 | * |
434 | * png_struct is the cache of information used while reading or writing a single |
435 | * PNG file. One of these is always required, although the simplified API |
436 | * (below) hides the creation and destruction of it. |
437 | */ |
438 | typedef struct png_struct_def png_struct; |
439 | typedef const png_struct * png_const_structp; |
440 | typedef png_struct * png_structp; |
441 | typedef png_struct * * png_structpp; |
442 | |
443 | /* png_info contains information read from or to be written to a PNG file. One |
444 | * or more of these must exist while reading or creating a PNG file. The |
445 | * information is not used by libpng during read but is used to control what |
446 | * gets written when a PNG file is created. "png_get_" function calls read |
447 | * information during read and "png_set_" functions calls write information |
448 | * when creating a PNG. |
449 | * been moved into a separate header file that is not accessible to |
450 | * applications. Read libpng-manual.txt or libpng.3 for more info. |
451 | */ |
452 | typedef struct png_info_def png_info; |
453 | typedef png_info * png_infop; |
454 | typedef const png_info * png_const_infop; |
455 | typedef png_info * * png_infopp; |
456 | |
457 | /* Types with names ending 'p' are pointer types. The corresponding types with |
458 | * names ending 'rp' are identical pointer types except that the pointer is |
459 | * marked 'restrict', which means that it is the only pointer to the object |
460 | * passed to the function. Applications should not use the 'restrict' types; |
461 | * it is always valid to pass 'p' to a pointer with a function argument of the |
462 | * corresponding 'rp' type. Different compilers have different rules with |
463 | * regard to type matching in the presence of 'restrict'. For backward |
464 | * compatibility libpng callbacks never have 'restrict' in their parameters and, |
465 | * consequentially, writing portable application code is extremely difficult if |
466 | * an attempt is made to use 'restrict'. |
467 | */ |
468 | typedef png_struct * PNG_RESTRICT png_structrp; |
469 | typedef const png_struct * PNG_RESTRICT png_const_structrp; |
470 | typedef png_info * PNG_RESTRICT png_inforp; |
471 | typedef const png_info * PNG_RESTRICT png_const_inforp; |
472 | |
473 | /* Three color definitions. The order of the red, green, and blue, (and the |
474 | * exact size) is not important, although the size of the fields need to |
475 | * be png_byte or png_uint_16 (as defined below). |
476 | */ |
477 | typedef struct png_color_struct |
478 | { |
479 | png_byte red; |
480 | png_byte green; |
481 | png_byte blue; |
482 | } png_color; |
483 | typedef png_color * png_colorp; |
484 | typedef const png_color * png_const_colorp; |
485 | typedef png_color * * png_colorpp; |
486 | |
487 | typedef struct png_color_16_struct |
488 | { |
489 | png_byte index; /* used for palette files */ |
490 | png_uint_16 red; /* for use in red green blue files */ |
491 | png_uint_16 green; |
492 | png_uint_16 blue; |
493 | png_uint_16 gray; /* for use in grayscale files */ |
494 | } png_color_16; |
495 | typedef png_color_16 * png_color_16p; |
496 | typedef const png_color_16 * png_const_color_16p; |
497 | typedef png_color_16 * * png_color_16pp; |
498 | |
499 | typedef struct png_color_8_struct |
500 | { |
501 | png_byte red; /* for use in red green blue files */ |
502 | png_byte green; |
503 | png_byte blue; |
504 | png_byte gray; /* for use in grayscale files */ |
505 | png_byte alpha; /* for alpha channel files */ |
506 | } png_color_8; |
507 | typedef png_color_8 * png_color_8p; |
508 | typedef const png_color_8 * png_const_color_8p; |
509 | typedef png_color_8 * * png_color_8pp; |
510 | |
511 | /* |
512 | * The following two structures are used for the in-core representation |
513 | * of sPLT chunks. |
514 | */ |
515 | typedef struct png_sPLT_entry_struct |
516 | { |
517 | png_uint_16 red; |
518 | png_uint_16 green; |
519 | png_uint_16 blue; |
520 | png_uint_16 alpha; |
521 | png_uint_16 frequency; |
522 | } png_sPLT_entry; |
523 | typedef png_sPLT_entry * png_sPLT_entryp; |
524 | typedef const png_sPLT_entry * png_const_sPLT_entryp; |
525 | typedef png_sPLT_entry * * png_sPLT_entrypp; |
526 | |
527 | /* When the depth of the sPLT palette is 8 bits, the color and alpha samples |
528 | * occupy the LSB of their respective members, and the MSB of each member |
529 | * is zero-filled. The frequency member always occupies the full 16 bits. |
530 | */ |
531 | |
532 | typedef struct png_sPLT_struct |
533 | { |
534 | png_charp name; /* palette name */ |
535 | png_byte depth; /* depth of palette samples */ |
536 | png_sPLT_entryp entries; /* palette entries */ |
537 | png_int_32 nentries; /* number of palette entries */ |
538 | } png_sPLT_t; |
539 | typedef png_sPLT_t * png_sPLT_tp; |
540 | typedef const png_sPLT_t * png_const_sPLT_tp; |
541 | typedef png_sPLT_t * * png_sPLT_tpp; |
542 | |
543 | #ifdef PNG_TEXT_SUPPORTED |
544 | /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, |
545 | * and whether that contents is compressed or not. The "key" field |
546 | * points to a regular zero-terminated C string. The "text" fields can be a |
547 | * regular C string, an empty string, or a NULL pointer. |
548 | * However, the structure returned by png_get_text() will always contain |
549 | * the "text" field as a regular zero-terminated C string (possibly |
550 | * empty), never a NULL pointer, so it can be safely used in printf() and |
551 | * other string-handling functions. Note that the "itxt_length", "lang", and |
552 | * "lang_key" members of the structure only exist when the library is built |
553 | * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by |
554 | * default without iTXt support. Also note that when iTXt *is* supported, |
555 | * the "lang" and "lang_key" fields contain NULL pointers when the |
556 | * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or |
557 | * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the |
558 | * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag" |
559 | * which is always 0 or 1, or its "compression method" which is always 0. |
560 | */ |
561 | typedef struct png_text_struct |
562 | { |
563 | int compression; /* compression value: |
564 | -1: tEXt, none |
565 | 0: zTXt, deflate |
566 | 1: iTXt, none |
567 | 2: iTXt, deflate */ |
568 | png_charp key; /* keyword, 1-79 character description of "text" */ |
569 | png_charp text; /* comment, may be an empty string (ie "") |
570 | or a NULL pointer */ |
571 | size_t text_length; /* length of the text string */ |
572 | size_t itxt_length; /* length of the itxt string */ |
573 | png_charp lang; /* language code, 0-79 characters |
574 | or a NULL pointer */ |
575 | png_charp lang_key; /* keyword translated UTF-8 string, 0 or more |
576 | chars or a NULL pointer */ |
577 | } png_text; |
578 | typedef png_text * png_textp; |
579 | typedef const png_text * png_const_textp; |
580 | typedef png_text * * png_textpp; |
581 | #endif |
582 | |
583 | /* Supported compression types for text in PNG files (tEXt, and zTXt). |
584 | * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ |
585 | #define PNG_TEXT_COMPRESSION_NONE_WR -3 |
586 | #define PNG_TEXT_COMPRESSION_zTXt_WR -2 |
587 | #define PNG_TEXT_COMPRESSION_NONE -1 |
588 | #define PNG_TEXT_COMPRESSION_zTXt 0 |
589 | #define PNG_ITXT_COMPRESSION_NONE 1 |
590 | #define PNG_ITXT_COMPRESSION_zTXt 2 |
591 | #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ |
592 | |
593 | /* png_time is a way to hold the time in an machine independent way. |
594 | * Two conversions are provided, both from time_t and struct tm. There |
595 | * is no portable way to convert to either of these structures, as far |
596 | * as I know. If you know of a portable way, send it to me. As a side |
597 | * note - PNG has always been Year 2000 compliant! |
598 | */ |
599 | typedef struct png_time_struct |
600 | { |
601 | png_uint_16 year; /* full year, as in, 1995 */ |
602 | png_byte month; /* month of year, 1 - 12 */ |
603 | png_byte day; /* day of month, 1 - 31 */ |
604 | png_byte hour; /* hour of day, 0 - 23 */ |
605 | png_byte minute; /* minute of hour, 0 - 59 */ |
606 | png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ |
607 | } png_time; |
608 | typedef png_time * png_timep; |
609 | typedef const png_time * png_const_timep; |
610 | typedef png_time * * png_timepp; |
611 | |
612 | #if defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) ||\ |
613 | defined(PNG_USER_CHUNKS_SUPPORTED) |
614 | /* png_unknown_chunk is a structure to hold queued chunks for which there is |
615 | * no specific support. The idea is that we can use this to queue |
616 | * up private chunks for output even though the library doesn't actually |
617 | * know about their semantics. |
618 | * |
619 | * The data in the structure is set by libpng on read and used on write. |
620 | */ |
621 | typedef struct png_unknown_chunk_t |
622 | { |
623 | png_byte name[5]; /* Textual chunk name with '\0' terminator */ |
624 | png_byte *data; /* Data, should not be modified on read! */ |
625 | size_t size; |
626 | |
627 | /* On write 'location' must be set using the flag values listed below. |
628 | * Notice that on read it is set by libpng however the values stored have |
629 | * more bits set than are listed below. Always treat the value as a |
630 | * bitmask. On write set only one bit - setting multiple bits may cause the |
631 | * chunk to be written in multiple places. |
632 | */ |
633 | png_byte location; /* mode of operation at read time */ |
634 | } |
635 | png_unknown_chunk; |
636 | |
637 | typedef png_unknown_chunk * png_unknown_chunkp; |
638 | typedef const png_unknown_chunk * png_const_unknown_chunkp; |
639 | typedef png_unknown_chunk * * png_unknown_chunkpp; |
640 | #endif |
641 | |
642 | /* Flag values for the unknown chunk location byte. */ |
643 | #define PNG_HAVE_IHDR 0x01 |
644 | #define PNG_HAVE_PLTE 0x02 |
645 | #define PNG_AFTER_IDAT 0x08 |
646 | |
647 | /* Maximum positive integer used in PNG is (2^31)-1 */ |
648 | #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) |
649 | #define PNG_UINT_32_MAX ((png_uint_32)(-1)) |
650 | #define PNG_SIZE_MAX ((size_t)(-1)) |
651 | |
652 | /* These are constants for fixed point values encoded in the |
653 | * PNG specification manner (x100000) |
654 | */ |
655 | #define PNG_FP_1 100000 |
656 | #define PNG_FP_HALF 50000 |
657 | #define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) |
658 | #define PNG_FP_MIN (-PNG_FP_MAX) |
659 | |
660 | /* These describe the color_type field in png_info. */ |
661 | /* color type masks */ |
662 | #define PNG_COLOR_MASK_PALETTE 1 |
663 | #define PNG_COLOR_MASK_COLOR 2 |
664 | #define PNG_COLOR_MASK_ALPHA 4 |
665 | |
666 | /* color types. Note that not all combinations are legal */ |
667 | #define PNG_COLOR_TYPE_GRAY 0 |
668 | #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) |
669 | #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) |
670 | #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) |
671 | #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) |
672 | /* aliases */ |
673 | #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA |
674 | #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA |
675 | |
676 | /* This is for compression type. PNG 1.0-1.2 only define the single type. */ |
677 | #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ |
678 | #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE |
679 | |
680 | /* This is for filter type. PNG 1.0-1.2 only define the single type. */ |
681 | #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ |
682 | #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ |
683 | #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE |
684 | |
685 | /* These are for the interlacing type. These values should NOT be changed. */ |
686 | #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ |
687 | #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ |
688 | #define PNG_INTERLACE_LAST 2 /* Not a valid value */ |
689 | |
690 | /* These are for the oFFs chunk. These values should NOT be changed. */ |
691 | #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ |
692 | #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ |
693 | #define PNG_OFFSET_LAST 2 /* Not a valid value */ |
694 | |
695 | /* These are for the pCAL chunk. These values should NOT be changed. */ |
696 | #define PNG_EQUATION_LINEAR 0 /* Linear transformation */ |
697 | #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ |
698 | #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ |
699 | #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ |
700 | #define PNG_EQUATION_LAST 4 /* Not a valid value */ |
701 | |
702 | /* These are for the sCAL chunk. These values should NOT be changed. */ |
703 | #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ |
704 | #define PNG_SCALE_METER 1 /* meters per pixel */ |
705 | #define PNG_SCALE_RADIAN 2 /* radians per pixel */ |
706 | #define PNG_SCALE_LAST 3 /* Not a valid value */ |
707 | |
708 | /* These are for the pHYs chunk. These values should NOT be changed. */ |
709 | #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ |
710 | #define PNG_RESOLUTION_METER 1 /* pixels/meter */ |
711 | #define PNG_RESOLUTION_LAST 2 /* Not a valid value */ |
712 | |
713 | /* These are for the sRGB chunk. These values should NOT be changed. */ |
714 | #define PNG_sRGB_INTENT_PERCEPTUAL 0 |
715 | #define PNG_sRGB_INTENT_RELATIVE 1 |
716 | #define PNG_sRGB_INTENT_SATURATION 2 |
717 | #define PNG_sRGB_INTENT_ABSOLUTE 3 |
718 | #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ |
719 | |
720 | /* This is for text chunks */ |
721 | #define PNG_KEYWORD_MAX_LENGTH 79 |
722 | |
723 | /* Maximum number of entries in PLTE/sPLT/tRNS arrays */ |
724 | #define PNG_MAX_PALETTE_LENGTH 256 |
725 | |
726 | /* These determine if an ancillary chunk's data has been successfully read |
727 | * from the PNG header, or if the application has filled in the corresponding |
728 | * data in the info_struct to be written into the output file. The values |
729 | * of the PNG_INFO_<chunk> defines should NOT be changed. |
730 | */ |
731 | #define PNG_INFO_gAMA 0x0001U |
732 | #define PNG_INFO_sBIT 0x0002U |
733 | #define PNG_INFO_cHRM 0x0004U |
734 | #define PNG_INFO_PLTE 0x0008U |
735 | #define PNG_INFO_tRNS 0x0010U |
736 | #define PNG_INFO_bKGD 0x0020U |
737 | #define PNG_INFO_hIST 0x0040U |
738 | #define PNG_INFO_pHYs 0x0080U |
739 | #define PNG_INFO_oFFs 0x0100U |
740 | #define PNG_INFO_tIME 0x0200U |
741 | #define PNG_INFO_pCAL 0x0400U |
742 | #define PNG_INFO_sRGB 0x0800U /* GR-P, 0.96a */ |
743 | #define PNG_INFO_iCCP 0x1000U /* ESR, 1.0.6 */ |
744 | #define PNG_INFO_sPLT 0x2000U /* ESR, 1.0.6 */ |
745 | #define PNG_INFO_sCAL 0x4000U /* ESR, 1.0.6 */ |
746 | #define PNG_INFO_IDAT 0x8000U /* ESR, 1.0.6 */ |
747 | #define PNG_INFO_eXIf 0x10000U /* GR-P, 1.6.31 */ |
748 | |
749 | /* This is used for the transformation routines, as some of them |
750 | * change these values for the row. It also should enable using |
751 | * the routines for other purposes. |
752 | */ |
753 | typedef struct png_row_info_struct |
754 | { |
755 | png_uint_32 width; /* width of row */ |
756 | size_t rowbytes; /* number of bytes in row */ |
757 | png_byte color_type; /* color type of row */ |
758 | png_byte bit_depth; /* bit depth of row */ |
759 | png_byte channels; /* number of channels (1, 2, 3, or 4) */ |
760 | png_byte pixel_depth; /* bits per pixel (depth * channels) */ |
761 | } png_row_info; |
762 | |
763 | typedef png_row_info * png_row_infop; |
764 | typedef png_row_info * * png_row_infopp; |
765 | |
766 | /* These are the function types for the I/O functions and for the functions |
767 | * that allow the user to override the default I/O functions with his or her |
768 | * own. The png_error_ptr type should match that of user-supplied warning |
769 | * and error functions, while the png_rw_ptr type should match that of the |
770 | * user read/write data functions. Note that the 'write' function must not |
771 | * modify the buffer it is passed. The 'read' function, on the other hand, is |
772 | * expected to return the read data in the buffer. |
773 | */ |
774 | typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); |
775 | typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, size_t)); |
776 | typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); |
777 | typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, |
778 | int)); |
779 | typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, |
780 | int)); |
781 | |
782 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
783 | typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); |
784 | typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); |
785 | |
786 | /* The following callback receives png_uint_32 row_number, int pass for the |
787 | * png_bytep data of the row. When transforming an interlaced image the |
788 | * row number is the row number within the sub-image of the interlace pass, so |
789 | * the value will increase to the height of the sub-image (not the full image) |
790 | * then reset to 0 for the next pass. |
791 | * |
792 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
793 | * find the output pixel (x,y) given an interlaced sub-image pixel |
794 | * (row,col,pass). (See below for these macros.) |
795 | */ |
796 | typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, |
797 | png_uint_32, int)); |
798 | #endif |
799 | |
800 | #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ |
801 | defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) |
802 | typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, |
803 | png_bytep)); |
804 | #endif |
805 | |
806 | #ifdef PNG_USER_CHUNKS_SUPPORTED |
807 | typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, |
808 | png_unknown_chunkp)); |
809 | #endif |
810 | #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED |
811 | /* not used anywhere */ |
812 | /* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); */ |
813 | #endif |
814 | |
815 | #ifdef PNG_SETJMP_SUPPORTED |
816 | /* This must match the function definition in <setjmp.h>, and the application |
817 | * must include this before png.h to obtain the definition of jmp_buf. The |
818 | * function is required to be PNG_NORETURN, but this is not checked. If the |
819 | * function does return the application will crash via an abort() or similar |
820 | * system level call. |
821 | * |
822 | * If you get a warning here while building the library you may need to make |
823 | * changes to ensure that pnglibconf.h records the calling convention used by |
824 | * your compiler. This may be very difficult - try using a different compiler |
825 | * to build the library! |
826 | */ |
827 | PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); |
828 | #endif |
829 | |
830 | /* Transform masks for the high-level interface */ |
831 | #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ |
832 | #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ |
833 | #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ |
834 | #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ |
835 | #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ |
836 | #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ |
837 | #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ |
838 | #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ |
839 | #define PNG_TRANSFORM_BGR 0x0080 /* read and write */ |
840 | #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ |
841 | #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ |
842 | #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ |
843 | #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ |
844 | /* Added to libpng-1.2.34 */ |
845 | #define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER |
846 | #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ |
847 | /* Added to libpng-1.4.0 */ |
848 | #define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ |
849 | /* Added to libpng-1.5.4 */ |
850 | #define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ |
851 | #if ~0U > 0xffffU /* or else this might break on a 16-bit machine */ |
852 | #define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ |
853 | #endif |
854 | |
855 | /* Flags for MNG supported features */ |
856 | #define PNG_FLAG_MNG_EMPTY_PLTE 0x01 |
857 | #define PNG_FLAG_MNG_FILTER_64 0x04 |
858 | #define PNG_ALL_MNG_FEATURES 0x05 |
859 | |
860 | /* NOTE: prior to 1.5 these functions had no 'API' style declaration, |
861 | * this allowed the zlib default functions to be used on Windows |
862 | * platforms. In 1.5 the zlib default malloc (which just calls malloc and |
863 | * ignores the first argument) should be completely compatible with the |
864 | * following. |
865 | */ |
866 | typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, |
867 | png_alloc_size_t)); |
868 | typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); |
869 | |
870 | /* Section 4: exported functions |
871 | * Here are the function definitions most commonly used. This is not |
872 | * the place to find out how to use libpng. See libpng-manual.txt for the |
873 | * full explanation, see example.c for the summary. This just provides |
874 | * a simple one line description of the use of each function. |
875 | * |
876 | * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in |
877 | * pngconf.h and in the *.dfn files in the scripts directory. |
878 | * |
879 | * PNG_EXPORT(ordinal, type, name, (args)); |
880 | * |
881 | * ordinal: ordinal that is used while building |
882 | * *.def files. The ordinal value is only |
883 | * relevant when preprocessing png.h with |
884 | * the *.dfn files for building symbol table |
885 | * entries, and are removed by pngconf.h. |
886 | * type: return type of the function |
887 | * name: function name |
888 | * args: function arguments, with types |
889 | * |
890 | * When we wish to append attributes to a function prototype we use |
891 | * the PNG_EXPORTA() macro instead. |
892 | * |
893 | * PNG_EXPORTA(ordinal, type, name, (args), attributes); |
894 | * |
895 | * ordinal, type, name, and args: same as in PNG_EXPORT(). |
896 | * attributes: function attributes |
897 | */ |
898 | |
899 | /* Returns the version number of the library */ |
900 | PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); |
901 | |
902 | /* Tell lib we have already handled the first <num_bytes> magic bytes. |
903 | * Handling more than 8 bytes from the beginning of the file is an error. |
904 | */ |
905 | PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes)); |
906 | |
907 | /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a |
908 | * PNG file. Returns zero if the supplied bytes match the 8-byte PNG |
909 | * signature, and non-zero otherwise. Having num_to_check == 0 or |
910 | * start > 7 will always fail (i.e. return non-zero). |
911 | */ |
912 | PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, size_t start, |
913 | size_t num_to_check)); |
914 | |
915 | /* Simple signature checking function. This is the same as calling |
916 | * png_check_sig(sig, n) := (png_sig_cmp(sig, 0, n) == 0). |
917 | */ |
918 | #define png_check_sig(sig, n) (png_sig_cmp((sig), 0, (n)) == 0) /* DEPRECATED */ |
919 | |
920 | /* Allocate and initialize png_ptr struct for reading, and any other memory. */ |
921 | PNG_EXPORTA(4, png_structp, png_create_read_struct, |
922 | (png_const_charp user_png_ver, png_voidp error_ptr, |
923 | png_error_ptr error_fn, png_error_ptr warn_fn), |
924 | PNG_ALLOCATED); |
925 | |
926 | /* Allocate and initialize png_ptr struct for writing, and any other memory */ |
927 | PNG_EXPORTA(5, png_structp, png_create_write_struct, |
928 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
929 | png_error_ptr warn_fn), |
930 | PNG_ALLOCATED); |
931 | |
932 | PNG_EXPORT(6, size_t, png_get_compression_buffer_size, |
933 | (png_const_structrp png_ptr)); |
934 | |
935 | PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr, |
936 | size_t size)); |
937 | |
938 | /* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp |
939 | * match up. |
940 | */ |
941 | #ifdef PNG_SETJMP_SUPPORTED |
942 | /* This function returns the jmp_buf built in to *png_ptr. It must be |
943 | * supplied with an appropriate 'longjmp' function to use on that jmp_buf |
944 | * unless the default error function is overridden in which case NULL is |
945 | * acceptable. The size of the jmp_buf is checked against the actual size |
946 | * allocated by the library - the call will return NULL on a mismatch |
947 | * indicating an ABI mismatch. |
948 | */ |
949 | PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr, |
950 | png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); |
951 | # define png_jmpbuf(png_ptr) \ |
952 | (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf)))) |
953 | #else |
954 | # define png_jmpbuf(png_ptr) \ |
955 | (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) |
956 | #endif |
957 | /* This function should be used by libpng applications in place of |
958 | * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it |
959 | * will use it; otherwise it will call PNG_ABORT(). This function was |
960 | * added in libpng-1.5.0. |
961 | */ |
962 | PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val), |
963 | PNG_NORETURN); |
964 | |
965 | #ifdef PNG_READ_SUPPORTED |
966 | /* Reset the compression stream */ |
967 | PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED); |
968 | #endif |
969 | |
970 | /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ |
971 | #ifdef PNG_USER_MEM_SUPPORTED |
972 | PNG_EXPORTA(11, png_structp, png_create_read_struct_2, |
973 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
974 | png_error_ptr warn_fn, |
975 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
976 | PNG_ALLOCATED); |
977 | PNG_EXPORTA(12, png_structp, png_create_write_struct_2, |
978 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
979 | png_error_ptr warn_fn, |
980 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
981 | PNG_ALLOCATED); |
982 | #endif |
983 | |
984 | /* Write the PNG file signature. */ |
985 | PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr)); |
986 | |
987 | /* Write a PNG chunk - size, type, (optional) data, CRC. */ |
988 | PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep |
989 | chunk_name, png_const_bytep data, size_t length)); |
990 | |
991 | /* Write the start of a PNG chunk - length and chunk name. */ |
992 | PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr, |
993 | png_const_bytep chunk_name, png_uint_32 length)); |
994 | |
995 | /* Write the data of a PNG chunk started with png_write_chunk_start(). */ |
996 | PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr, |
997 | png_const_bytep data, size_t length)); |
998 | |
999 | /* Finish a chunk started with png_write_chunk_start() (includes CRC). */ |
1000 | PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr)); |
1001 | |
1002 | /* Allocate and initialize the info structure */ |
1003 | PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr), |
1004 | PNG_ALLOCATED); |
1005 | |
1006 | /* DEPRECATED: this function allowed init structures to be created using the |
1007 | * default allocation method (typically malloc). Use is deprecated in 1.6.0 and |
1008 | * the API will be removed in the future. |
1009 | */ |
1010 | PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr, |
1011 | size_t png_info_struct_size), PNG_DEPRECATED); |
1012 | |
1013 | /* Writes all the PNG information before the image. */ |
1014 | PNG_EXPORT(20, void, png_write_info_before_PLTE, |
1015 | (png_structrp png_ptr, png_const_inforp info_ptr)); |
1016 | PNG_EXPORT(21, void, png_write_info, |
1017 | (png_structrp png_ptr, png_const_inforp info_ptr)); |
1018 | |
1019 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
1020 | /* Read the information before the actual image data. */ |
1021 | PNG_EXPORT(22, void, png_read_info, |
1022 | (png_structrp png_ptr, png_inforp info_ptr)); |
1023 | #endif |
1024 | |
1025 | #ifdef PNG_TIME_RFC1123_SUPPORTED |
1026 | /* Convert to a US string format: there is no localization support in this |
1027 | * routine. The original implementation used a 29 character buffer in |
1028 | * png_struct, this will be removed in future versions. |
1029 | */ |
1030 | #if PNG_LIBPNG_VER < 10700 |
1031 | /* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */ |
1032 | PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr, |
1033 | png_const_timep ptime),PNG_DEPRECATED); |
1034 | #endif |
1035 | PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29], |
1036 | png_const_timep ptime)); |
1037 | #endif |
1038 | |
1039 | #ifdef PNG_CONVERT_tIME_SUPPORTED |
1040 | /* Convert from a struct tm to png_time */ |
1041 | PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, |
1042 | const struct tm * ttime)); |
1043 | |
1044 | /* Convert from time_t to png_time. Uses gmtime() */ |
1045 | PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime)); |
1046 | #endif /* CONVERT_tIME */ |
1047 | |
1048 | #ifdef PNG_READ_EXPAND_SUPPORTED |
1049 | /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ |
1050 | PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr)); |
1051 | PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr)); |
1052 | PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr)); |
1053 | PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr)); |
1054 | #endif |
1055 | |
1056 | #ifdef PNG_READ_EXPAND_16_SUPPORTED |
1057 | /* Expand to 16-bit channels, forces conversion of palette to RGB and expansion |
1058 | * of a tRNS chunk if present. |
1059 | */ |
1060 | PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr)); |
1061 | #endif |
1062 | |
1063 | #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
1064 | /* Use blue, green, red order for pixels. */ |
1065 | PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr)); |
1066 | #endif |
1067 | |
1068 | #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED |
1069 | /* Expand the grayscale to 24-bit RGB if necessary. */ |
1070 | PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr)); |
1071 | #endif |
1072 | |
1073 | #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED |
1074 | /* Reduce RGB to grayscale. */ |
1075 | #define PNG_ERROR_ACTION_NONE 1 |
1076 | #define PNG_ERROR_ACTION_WARN 2 |
1077 | #define PNG_ERROR_ACTION_ERROR 3 |
1078 | #define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ |
1079 | |
1080 | PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr, |
1081 | int error_action, double red, double green)) |
1082 | PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr, |
1083 | int error_action, png_fixed_point red, png_fixed_point green)) |
1084 | |
1085 | PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp |
1086 | png_ptr)); |
1087 | #endif |
1088 | |
1089 | #ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED |
1090 | PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, |
1091 | png_colorp palette)); |
1092 | #endif |
1093 | |
1094 | #ifdef PNG_READ_ALPHA_MODE_SUPPORTED |
1095 | /* How the alpha channel is interpreted - this affects how the color channels |
1096 | * of a PNG file are returned to the calling application when an alpha channel, |
1097 | * or a tRNS chunk in a palette file, is present. |
1098 | * |
1099 | * This has no effect on the way pixels are written into a PNG output |
1100 | * datastream. The color samples in a PNG datastream are never premultiplied |
1101 | * with the alpha samples. |
1102 | * |
1103 | * The default is to return data according to the PNG specification: the alpha |
1104 | * channel is a linear measure of the contribution of the pixel to the |
1105 | * corresponding composited pixel, and the color channels are unassociated |
1106 | * (not premultiplied). The gamma encoded color channels must be scaled |
1107 | * according to the contribution and to do this it is necessary to undo |
1108 | * the encoding, scale the color values, perform the composition and re-encode |
1109 | * the values. This is the 'PNG' mode. |
1110 | * |
1111 | * The alternative is to 'associate' the alpha with the color information by |
1112 | * storing color channel values that have been scaled by the alpha. |
1113 | * image. These are the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' modes |
1114 | * (the latter being the two common names for associated alpha color channels). |
1115 | * |
1116 | * For the 'OPTIMIZED' mode, a pixel is treated as opaque only if the alpha |
1117 | * value is equal to the maximum value. |
1118 | * |
1119 | * The final choice is to gamma encode the alpha channel as well. This is |
1120 | * broken because, in practice, no implementation that uses this choice |
1121 | * correctly undoes the encoding before handling alpha composition. Use this |
1122 | * choice only if other serious errors in the software or hardware you use |
1123 | * mandate it; the typical serious error is for dark halos to appear around |
1124 | * opaque areas of the composited PNG image because of arithmetic overflow. |
1125 | * |
1126 | * The API function png_set_alpha_mode specifies which of these choices to use |
1127 | * with an enumerated 'mode' value and the gamma of the required output: |
1128 | */ |
1129 | #define PNG_ALPHA_PNG 0 /* according to the PNG standard */ |
1130 | #define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ |
1131 | #define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ |
1132 | #define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ |
1133 | #define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ |
1134 | #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ |
1135 | |
1136 | PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode, |
1137 | double output_gamma)) |
1138 | PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr, |
1139 | int mode, png_fixed_point output_gamma)) |
1140 | #endif |
1141 | |
1142 | #if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) |
1143 | /* The output_gamma value is a screen gamma in libpng terminology: it expresses |
1144 | * how to decode the output values, not how they are encoded. |
1145 | */ |
1146 | #define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ |
1147 | #define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ |
1148 | #define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ |
1149 | #define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ |
1150 | #endif |
1151 | |
1152 | /* The following are examples of calls to png_set_alpha_mode to achieve the |
1153 | * required overall gamma correction and, where necessary, alpha |
1154 | * premultiplication. |
1155 | * |
1156 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
1157 | * This is the default libpng handling of the alpha channel - it is not |
1158 | * pre-multiplied into the color components. In addition the call states |
1159 | * that the output is for a sRGB system and causes all PNG files without gAMA |
1160 | * chunks to be assumed to be encoded using sRGB. |
1161 | * |
1162 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
1163 | * In this case the output is assumed to be something like an sRGB conformant |
1164 | * display preceded by a power-law lookup table of power 1.45. This is how |
1165 | * early Mac systems behaved. |
1166 | * |
1167 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); |
1168 | * This is the classic Jim Blinn approach and will work in academic |
1169 | * environments where everything is done by the book. It has the shortcoming |
1170 | * of assuming that input PNG data with no gamma information is linear - this |
1171 | * is unlikely to be correct unless the PNG files where generated locally. |
1172 | * Most of the time the output precision will be so low as to show |
1173 | * significant banding in dark areas of the image. |
1174 | * |
1175 | * png_set_expand_16(pp); |
1176 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); |
1177 | * This is a somewhat more realistic Jim Blinn inspired approach. PNG files |
1178 | * are assumed to have the sRGB encoding if not marked with a gamma value and |
1179 | * the output is always 16 bits per component. This permits accurate scaling |
1180 | * and processing of the data. If you know that your input PNG files were |
1181 | * generated locally you might need to replace PNG_DEFAULT_sRGB with the |
1182 | * correct value for your system. |
1183 | * |
1184 | * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); |
1185 | * If you just need to composite the PNG image onto an existing background |
1186 | * and if you control the code that does this you can use the optimization |
1187 | * setting. In this case you just copy completely opaque pixels to the |
1188 | * output. For pixels that are not completely transparent (you just skip |
1189 | * those) you do the composition math using png_composite or png_composite_16 |
1190 | * below then encode the resultant 8-bit or 16-bit values to match the output |
1191 | * encoding. |
1192 | * |
1193 | * Other cases |
1194 | * If neither the PNG nor the standard linear encoding work for you because |
1195 | * of the software or hardware you use then you have a big problem. The PNG |
1196 | * case will probably result in halos around the image. The linear encoding |
1197 | * will probably result in a washed out, too bright, image (it's actually too |
1198 | * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably |
1199 | * substantially reduce the halos. Alternatively try: |
1200 | * |
1201 | * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); |
1202 | * This option will also reduce the halos, but there will be slight dark |
1203 | * halos round the opaque parts of the image where the background is light. |
1204 | * In the OPTIMIZED mode the halos will be light halos where the background |
1205 | * is dark. Take your pick - the halos are unavoidable unless you can get |
1206 | * your hardware/software fixed! (The OPTIMIZED approach is slightly |
1207 | * faster.) |
1208 | * |
1209 | * When the default gamma of PNG files doesn't match the output gamma. |
1210 | * If you have PNG files with no gamma information png_set_alpha_mode allows |
1211 | * you to provide a default gamma, but it also sets the output gamma to the |
1212 | * matching value. If you know your PNG files have a gamma that doesn't |
1213 | * match the output you can take advantage of the fact that |
1214 | * png_set_alpha_mode always sets the output gamma but only sets the PNG |
1215 | * default if it is not already set: |
1216 | * |
1217 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
1218 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
1219 | * The first call sets both the default and the output gamma values, the |
1220 | * second call overrides the output gamma without changing the default. This |
1221 | * is easier than achieving the same effect with png_set_gamma. You must use |
1222 | * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will |
1223 | * fire if more than one call to png_set_alpha_mode and png_set_background is |
1224 | * made in the same read operation, however multiple calls with PNG_ALPHA_PNG |
1225 | * are ignored. |
1226 | */ |
1227 | |
1228 | #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED |
1229 | PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr)); |
1230 | #endif |
1231 | |
1232 | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ |
1233 | defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
1234 | PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr)); |
1235 | #endif |
1236 | |
1237 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ |
1238 | defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
1239 | PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr)); |
1240 | #endif |
1241 | |
1242 | #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) |
1243 | /* Add a filler byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */ |
1244 | PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler, |
1245 | int flags)); |
1246 | /* The values of the PNG_FILLER_ defines should NOT be changed */ |
1247 | # define PNG_FILLER_BEFORE 0 |
1248 | # define PNG_FILLER_AFTER 1 |
1249 | /* Add an alpha byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */ |
1250 | PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr, |
1251 | png_uint_32 filler, int flags)); |
1252 | #endif /* READ_FILLER || WRITE_FILLER */ |
1253 | |
1254 | #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
1255 | /* Swap bytes in 16-bit depth files. */ |
1256 | PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr)); |
1257 | #endif |
1258 | |
1259 | #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) |
1260 | /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ |
1261 | PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr)); |
1262 | #endif |
1263 | |
1264 | #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ |
1265 | defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
1266 | /* Swap packing order of pixels in bytes. */ |
1267 | PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr)); |
1268 | #endif |
1269 | |
1270 | #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) |
1271 | /* Converts files to legal bit depths. */ |
1272 | PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p |
1273 | true_bits)); |
1274 | #endif |
1275 | |
1276 | #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ |
1277 | defined(PNG_WRITE_INTERLACING_SUPPORTED) |
1278 | /* Have the code handle the interlacing. Returns the number of passes. |
1279 | * MUST be called before png_read_update_info or png_start_read_image, |
1280 | * otherwise it will not have the desired effect. Note that it is still |
1281 | * necessary to call png_read_row or png_read_rows png_get_image_height |
1282 | * times for each pass. |
1283 | */ |
1284 | PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr)); |
1285 | #endif |
1286 | |
1287 | #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) |
1288 | /* Invert monochrome files */ |
1289 | PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr)); |
1290 | #endif |
1291 | |
1292 | #ifdef PNG_READ_BACKGROUND_SUPPORTED |
1293 | /* Handle alpha and tRNS by replacing with a background color. Prior to |
1294 | * libpng-1.5.4 this API must not be called before the PNG file header has been |
1295 | * read. Doing so will result in unexpected behavior and possible warnings or |
1296 | * errors if the PNG file contains a bKGD chunk. |
1297 | */ |
1298 | PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr, |
1299 | png_const_color_16p background_color, int background_gamma_code, |
1300 | int need_expand, double background_gamma)) |
1301 | PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr, |
1302 | png_const_color_16p background_color, int background_gamma_code, |
1303 | int need_expand, png_fixed_point background_gamma)) |
1304 | #endif |
1305 | #ifdef PNG_READ_BACKGROUND_SUPPORTED |
1306 | # define PNG_BACKGROUND_GAMMA_UNKNOWN 0 |
1307 | # define PNG_BACKGROUND_GAMMA_SCREEN 1 |
1308 | # define PNG_BACKGROUND_GAMMA_FILE 2 |
1309 | # define PNG_BACKGROUND_GAMMA_UNIQUE 3 |
1310 | #endif |
1311 | |
1312 | #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED |
1313 | /* Scale a 16-bit depth file down to 8-bit, accurately. */ |
1314 | PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr)); |
1315 | #endif |
1316 | |
1317 | #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED |
1318 | #define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */ |
1319 | /* Strip the second byte of information from a 16-bit depth file. */ |
1320 | PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr)); |
1321 | #endif |
1322 | |
1323 | #ifdef PNG_READ_QUANTIZE_SUPPORTED |
1324 | /* Turn on quantizing, and reduce the palette to the number of colors |
1325 | * available. |
1326 | */ |
1327 | PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr, |
1328 | png_colorp palette, int num_palette, int maximum_colors, |
1329 | png_const_uint_16p histogram, int full_quantize)); |
1330 | #endif |
1331 | |
1332 | #ifdef PNG_READ_GAMMA_SUPPORTED |
1333 | /* The threshold on gamma processing is configurable but hard-wired into the |
1334 | * library. The following is the floating point variant. |
1335 | */ |
1336 | #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) |
1337 | |
1338 | /* Handle gamma correction. Screen_gamma=(display_exponent). |
1339 | * NOTE: this API simply sets the screen and file gamma values. It will |
1340 | * therefore override the value for gamma in a PNG file if it is called after |
1341 | * the file header has been read - use with care - call before reading the PNG |
1342 | * file for best results! |
1343 | * |
1344 | * These routines accept the same gamma values as png_set_alpha_mode (described |
1345 | * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either |
1346 | * API (floating point or fixed.) Notice, however, that the 'file_gamma' value |
1347 | * is the inverse of a 'screen gamma' value. |
1348 | */ |
1349 | PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr, |
1350 | double screen_gamma, double override_file_gamma)) |
1351 | PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr, |
1352 | png_fixed_point screen_gamma, png_fixed_point override_file_gamma)) |
1353 | #endif |
1354 | |
1355 | #ifdef PNG_WRITE_FLUSH_SUPPORTED |
1356 | /* Set how many lines between output flushes - 0 for no flushing */ |
1357 | PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows)); |
1358 | /* Flush the current PNG output buffer */ |
1359 | PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr)); |
1360 | #endif |
1361 | |
1362 | /* Optional update palette with requested transformations */ |
1363 | PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr)); |
1364 | |
1365 | /* Optional call to update the users info structure */ |
1366 | PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr, |
1367 | png_inforp info_ptr)); |
1368 | |
1369 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
1370 | /* Read one or more rows of image data. */ |
1371 | PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row, |
1372 | png_bytepp display_row, png_uint_32 num_rows)); |
1373 | #endif |
1374 | |
1375 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
1376 | /* Read a row of data. */ |
1377 | PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row, |
1378 | png_bytep display_row)); |
1379 | #endif |
1380 | |
1381 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
1382 | /* Read the whole image into memory at once. */ |
1383 | PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image)); |
1384 | #endif |
1385 | |
1386 | /* Write a row of image data */ |
1387 | PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr, |
1388 | png_const_bytep row)); |
1389 | |
1390 | /* Write a few rows of image data: (*row) is not written; however, the type |
1391 | * is declared as writeable to maintain compatibility with previous versions |
1392 | * of libpng and to allow the 'display_row' array from read_rows to be passed |
1393 | * unchanged to write_rows. |
1394 | */ |
1395 | PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row, |
1396 | png_uint_32 num_rows)); |
1397 | |
1398 | /* Write the image data */ |
1399 | PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image)); |
1400 | |
1401 | /* Write the end of the PNG file. */ |
1402 | PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr, |
1403 | png_inforp info_ptr)); |
1404 | |
1405 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
1406 | /* Read the end of the PNG file. */ |
1407 | PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr)); |
1408 | #endif |
1409 | |
1410 | /* Free any memory associated with the png_info_struct */ |
1411 | PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr, |
1412 | png_infopp info_ptr_ptr)); |
1413 | |
1414 | /* Free any memory associated with the png_struct and the png_info_structs */ |
1415 | PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, |
1416 | png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); |
1417 | |
1418 | /* Free any memory associated with the png_struct and the png_info_structs */ |
1419 | PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, |
1420 | png_infopp info_ptr_ptr)); |
1421 | |
1422 | /* Set the libpng method of handling chunk CRC errors */ |
1423 | PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action, |
1424 | int ancil_action)); |
1425 | |
1426 | /* Values for png_set_crc_action() say how to handle CRC errors in |
1427 | * ancillary and critical chunks, and whether to use the data contained |
1428 | * therein. Note that it is impossible to "discard" data in a critical |
1429 | * chunk. For versions prior to 0.90, the action was always error/quit, |
1430 | * whereas in version 0.90 and later, the action for CRC errors in ancillary |
1431 | * chunks is warn/discard. These values should NOT be changed. |
1432 | * |
1433 | * value action:critical action:ancillary |
1434 | */ |
1435 | #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ |
1436 | #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ |
1437 | #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ |
1438 | #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ |
1439 | #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ |
1440 | #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ |
1441 | |
1442 | #ifdef PNG_WRITE_SUPPORTED |
1443 | /* These functions give the user control over the scan-line filtering in |
1444 | * libpng and the compression methods used by zlib. These functions are |
1445 | * mainly useful for testing, as the defaults should work with most users. |
1446 | * Those users who are tight on memory or want faster performance at the |
1447 | * expense of compression can modify them. See the compression library |
1448 | * header file (zlib.h) for an explanation of the compression functions. |
1449 | */ |
1450 | |
1451 | /* Set the filtering method(s) used by libpng. Currently, the only valid |
1452 | * value for "method" is 0. |
1453 | */ |
1454 | PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method, |
1455 | int filters)); |
1456 | #endif /* WRITE */ |
1457 | |
1458 | /* Flags for png_set_filter() to say which filters to use. The flags |
1459 | * are chosen so that they don't conflict with real filter types |
1460 | * below, in case they are supplied instead of the #defined constants. |
1461 | * These values should NOT be changed. |
1462 | */ |
1463 | #define PNG_NO_FILTERS 0x00 |
1464 | #define PNG_FILTER_NONE 0x08 |
1465 | #define PNG_FILTER_SUB 0x10 |
1466 | #define PNG_FILTER_UP 0x20 |
1467 | #define PNG_FILTER_AVG 0x40 |
1468 | #define PNG_FILTER_PAETH 0x80 |
1469 | #define PNG_FAST_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP) |
1470 | #define PNG_ALL_FILTERS (PNG_FAST_FILTERS | PNG_FILTER_AVG | PNG_FILTER_PAETH) |
1471 | |
1472 | /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. |
1473 | * These defines should NOT be changed. |
1474 | */ |
1475 | #define PNG_FILTER_VALUE_NONE 0 |
1476 | #define PNG_FILTER_VALUE_SUB 1 |
1477 | #define PNG_FILTER_VALUE_UP 2 |
1478 | #define PNG_FILTER_VALUE_AVG 3 |
1479 | #define PNG_FILTER_VALUE_PAETH 4 |
1480 | #define PNG_FILTER_VALUE_LAST 5 |
1481 | |
1482 | #ifdef PNG_WRITE_SUPPORTED |
1483 | #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* DEPRECATED */ |
1484 | PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr, |
1485 | int heuristic_method, int num_weights, png_const_doublep filter_weights, |
1486 | png_const_doublep filter_costs)) |
1487 | PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, |
1488 | (png_structrp png_ptr, int heuristic_method, int num_weights, |
1489 | png_const_fixed_point_p filter_weights, |
1490 | png_const_fixed_point_p filter_costs)) |
1491 | #endif /* WRITE_WEIGHTED_FILTER */ |
1492 | |
1493 | /* The following are no longer used and will be removed from libpng-1.7: */ |
1494 | #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ |
1495 | #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ |
1496 | #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ |
1497 | #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ |
1498 | |
1499 | /* Set the library compression level. Currently, valid values range from |
1500 | * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 |
1501 | * (0 - no compression, 9 - "maximal" compression). Note that tests have |
1502 | * shown that zlib compression levels 3-6 usually perform as well as level 9 |
1503 | * for PNG images, and do considerably fewer calculations. In the future, |
1504 | * these values may not correspond directly to the zlib compression levels. |
1505 | */ |
1506 | #ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED |
1507 | PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr, |
1508 | int level)); |
1509 | |
1510 | PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr, |
1511 | int mem_level)); |
1512 | |
1513 | PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr, |
1514 | int strategy)); |
1515 | |
1516 | /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
1517 | * smaller value of window_bits if it can do so safely. |
1518 | */ |
1519 | PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr, |
1520 | int window_bits)); |
1521 | |
1522 | PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr, |
1523 | int method)); |
1524 | #endif /* WRITE_CUSTOMIZE_COMPRESSION */ |
1525 | |
1526 | #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED |
1527 | /* Also set zlib parameters for compressing non-IDAT chunks */ |
1528 | PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr, |
1529 | int level)); |
1530 | |
1531 | PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr, |
1532 | int mem_level)); |
1533 | |
1534 | PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr, |
1535 | int strategy)); |
1536 | |
1537 | /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
1538 | * smaller value of window_bits if it can do so safely. |
1539 | */ |
1540 | PNG_EXPORT(225, void, png_set_text_compression_window_bits, |
1541 | (png_structrp png_ptr, int window_bits)); |
1542 | |
1543 | PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr, |
1544 | int method)); |
1545 | #endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */ |
1546 | #endif /* WRITE */ |
1547 | |
1548 | /* These next functions are called for input/output, memory, and error |
1549 | * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, |
1550 | * and call standard C I/O routines such as fread(), fwrite(), and |
1551 | * fprintf(). These functions can be made to use other I/O routines |
1552 | * at run time for those applications that need to handle I/O in a |
1553 | * different manner by calling png_set_???_fn(). See libpng-manual.txt for |
1554 | * more information. |
1555 | */ |
1556 | |
1557 | #ifdef PNG_STDIO_SUPPORTED |
1558 | /* Initialize the input/output for the PNG file to the default functions. */ |
1559 | PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp)); |
1560 | #endif |
1561 | |
1562 | /* Replace the (error and abort), and warning functions with user |
1563 | * supplied functions. If no messages are to be printed you must still |
1564 | * write and use replacement functions. The replacement error_fn should |
1565 | * still do a longjmp to the last setjmp location if you are using this |
1566 | * method of error handling. If error_fn or warning_fn is NULL, the |
1567 | * default function will be used. |
1568 | */ |
1569 | |
1570 | PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr, |
1571 | png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); |
1572 | |
1573 | /* Return the user pointer associated with the error functions */ |
1574 | PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr)); |
1575 | |
1576 | /* Replace the default data output functions with a user supplied one(s). |
1577 | * If buffered output is not used, then output_flush_fn can be set to NULL. |
1578 | * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time |
1579 | * output_flush_fn will be ignored (and thus can be NULL). |
1580 | * It is probably a mistake to use NULL for output_flush_fn if |
1581 | * write_data_fn is not also NULL unless you have built libpng with |
1582 | * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's |
1583 | * default flush function, which uses the standard *FILE structure, will |
1584 | * be used. |
1585 | */ |
1586 | PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr, |
1587 | png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); |
1588 | |
1589 | /* Replace the default data input function with a user supplied one. */ |
1590 | PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr, |
1591 | png_rw_ptr read_data_fn)); |
1592 | |
1593 | /* Return the user pointer associated with the I/O functions */ |
1594 | PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr)); |
1595 | |
1596 | PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr, |
1597 | png_read_status_ptr read_row_fn)); |
1598 | |
1599 | PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr, |
1600 | png_write_status_ptr write_row_fn)); |
1601 | |
1602 | #ifdef PNG_USER_MEM_SUPPORTED |
1603 | /* Replace the default memory allocation functions with user supplied one(s). */ |
1604 | PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr, |
1605 | png_malloc_ptr malloc_fn, png_free_ptr free_fn)); |
1606 | /* Return the user pointer associated with the memory functions */ |
1607 | PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr)); |
1608 | #endif |
1609 | |
1610 | #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED |
1611 | PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr, |
1612 | png_user_transform_ptr read_user_transform_fn)); |
1613 | #endif |
1614 | |
1615 | #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED |
1616 | PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr, |
1617 | png_user_transform_ptr write_user_transform_fn)); |
1618 | #endif |
1619 | |
1620 | #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED |
1621 | PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr, |
1622 | png_voidp user_transform_ptr, int user_transform_depth, |
1623 | int user_transform_channels)); |
1624 | /* Return the user pointer associated with the user transform functions */ |
1625 | PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, |
1626 | (png_const_structrp png_ptr)); |
1627 | #endif |
1628 | |
1629 | #ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED |
1630 | /* Return information about the row currently being processed. Note that these |
1631 | * APIs do not fail but will return unexpected results if called outside a user |
1632 | * transform callback. Also note that when transforming an interlaced image the |
1633 | * row number is the row number within the sub-image of the interlace pass, so |
1634 | * the value will increase to the height of the sub-image (not the full image) |
1635 | * then reset to 0 for the next pass. |
1636 | * |
1637 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
1638 | * find the output pixel (x,y) given an interlaced sub-image pixel |
1639 | * (row,col,pass). (See below for these macros.) |
1640 | */ |
1641 | PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp)); |
1642 | PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp)); |
1643 | #endif |
1644 | |
1645 | #ifdef PNG_READ_USER_CHUNKS_SUPPORTED |
1646 | /* This callback is called only for *unknown* chunks. If |
1647 | * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known |
1648 | * chunks to be treated as unknown, however in this case the callback must do |
1649 | * any processing required by the chunk (e.g. by calling the appropriate |
1650 | * png_set_ APIs.) |
1651 | * |
1652 | * There is no write support - on write, by default, all the chunks in the |
1653 | * 'unknown' list are written in the specified position. |
1654 | * |
1655 | * The integer return from the callback function is interpreted thus: |
1656 | * |
1657 | * negative: An error occurred; png_chunk_error will be called. |
1658 | * zero: The chunk was not handled, the chunk will be saved. A critical |
1659 | * chunk will cause an error at this point unless it is to be saved. |
1660 | * positive: The chunk was handled, libpng will ignore/discard it. |
1661 | * |
1662 | * See "INTERACTION WITH USER CHUNK CALLBACKS" below for important notes about |
1663 | * how this behavior will change in libpng 1.7 |
1664 | */ |
1665 | PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr, |
1666 | png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); |
1667 | #endif |
1668 | |
1669 | #ifdef PNG_USER_CHUNKS_SUPPORTED |
1670 | PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr)); |
1671 | #endif |
1672 | |
1673 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
1674 | /* Sets the function callbacks for the push reader, and a pointer to a |
1675 | * user-defined structure available to the callback functions. |
1676 | */ |
1677 | PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr, |
1678 | png_voidp progressive_ptr, png_progressive_info_ptr info_fn, |
1679 | png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); |
1680 | |
1681 | /* Returns the user pointer associated with the push read functions */ |
1682 | PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, |
1683 | (png_const_structrp png_ptr)); |
1684 | |
1685 | /* Function to be called when data becomes available */ |
1686 | PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr, |
1687 | png_inforp info_ptr, png_bytep buffer, size_t buffer_size)); |
1688 | |
1689 | /* A function which may be called *only* within png_process_data to stop the |
1690 | * processing of any more data. The function returns the number of bytes |
1691 | * remaining, excluding any that libpng has cached internally. A subsequent |
1692 | * call to png_process_data must supply these bytes again. If the argument |
1693 | * 'save' is set to true the routine will first save all the pending data and |
1694 | * will always return 0. |
1695 | */ |
1696 | PNG_EXPORT(219, size_t, png_process_data_pause, (png_structrp, int save)); |
1697 | |
1698 | /* A function which may be called *only* outside (after) a call to |
1699 | * png_process_data. It returns the number of bytes of data to skip in the |
1700 | * input. Normally it will return 0, but if it returns a non-zero value the |
1701 | * application must skip than number of bytes of input data and pass the |
1702 | * following data to the next call to png_process_data. |
1703 | */ |
1704 | PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp)); |
1705 | |
1706 | /* Function that combines rows. 'new_row' is a flag that should come from |
1707 | * the callback and be non-NULL if anything needs to be done; the library |
1708 | * stores its own version of the new data internally and ignores the passed |
1709 | * in value. |
1710 | */ |
1711 | PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr, |
1712 | png_bytep old_row, png_const_bytep new_row)); |
1713 | #endif /* PROGRESSIVE_READ */ |
1714 | |
1715 | PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr, |
1716 | png_alloc_size_t size), PNG_ALLOCATED); |
1717 | /* Added at libpng version 1.4.0 */ |
1718 | PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr, |
1719 | png_alloc_size_t size), PNG_ALLOCATED); |
1720 | |
1721 | /* Added at libpng version 1.2.4 */ |
1722 | PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr, |
1723 | png_alloc_size_t size), PNG_ALLOCATED); |
1724 | |
1725 | /* Frees a pointer allocated by png_malloc() */ |
1726 | PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr)); |
1727 | |
1728 | /* Free data that was allocated internally */ |
1729 | PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr, |
1730 | png_inforp info_ptr, png_uint_32 free_me, int num)); |
1731 | |
1732 | /* Reassign the responsibility for freeing existing data, whether allocated |
1733 | * by libpng or by the application; this works on the png_info structure passed |
1734 | * in, without changing the state for other png_info structures. |
1735 | */ |
1736 | PNG_EXPORT(99, void, png_data_freer, (png_const_structrp png_ptr, |
1737 | png_inforp info_ptr, int freer, png_uint_32 mask)); |
1738 | |
1739 | /* Assignments for png_data_freer */ |
1740 | #define PNG_DESTROY_WILL_FREE_DATA 1 |
1741 | #define PNG_SET_WILL_FREE_DATA 1 |
1742 | #define PNG_USER_WILL_FREE_DATA 2 |
1743 | /* Flags for png_ptr->free_me and info_ptr->free_me */ |
1744 | #define PNG_FREE_HIST 0x0008U |
1745 | #define PNG_FREE_ICCP 0x0010U |
1746 | #define PNG_FREE_SPLT 0x0020U |
1747 | #define PNG_FREE_ROWS 0x0040U |
1748 | #define PNG_FREE_PCAL 0x0080U |
1749 | #define PNG_FREE_SCAL 0x0100U |
1750 | #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED |
1751 | # define PNG_FREE_UNKN 0x0200U |
1752 | #endif |
1753 | /* PNG_FREE_LIST 0x0400U removed in 1.6.0 because it is ignored */ |
1754 | #define PNG_FREE_PLTE 0x1000U |
1755 | #define PNG_FREE_TRNS 0x2000U |
1756 | #define PNG_FREE_TEXT 0x4000U |
1757 | #define PNG_FREE_EXIF 0x8000U /* Added at libpng-1.6.31 */ |
1758 | #define PNG_FREE_ALL 0xffffU |
1759 | #define PNG_FREE_MUL 0x4220U /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ |
1760 | |
1761 | #ifdef PNG_USER_MEM_SUPPORTED |
1762 | PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr, |
1763 | png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED); |
1764 | PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr, |
1765 | png_voidp ptr), PNG_DEPRECATED); |
1766 | #endif |
1767 | |
1768 | #ifdef PNG_ERROR_TEXT_SUPPORTED |
1769 | /* Fatal error in PNG image of libpng - can't continue */ |
1770 | PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr, |
1771 | png_const_charp error_message), PNG_NORETURN); |
1772 | |
1773 | /* The same, but the chunk name is prepended to the error string. */ |
1774 | PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr, |
1775 | png_const_charp error_message), PNG_NORETURN); |
1776 | |
1777 | #else |
1778 | /* Fatal error in PNG image of libpng - can't continue */ |
1779 | PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN); |
1780 | # define png_error(s1,s2) png_err(s1) |
1781 | # define png_chunk_error(s1,s2) png_err(s1) |
1782 | #endif |
1783 | |
1784 | #ifdef PNG_WARNINGS_SUPPORTED |
1785 | /* Non-fatal error in libpng. Can continue, but may have a problem. */ |
1786 | PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr, |
1787 | png_const_charp warning_message)); |
1788 | |
1789 | /* Non-fatal error in libpng, chunk name is prepended to message. */ |
1790 | PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr, |
1791 | png_const_charp warning_message)); |
1792 | #else |
1793 | # define png_warning(s1,s2) ((void)(s1)) |
1794 | # define png_chunk_warning(s1,s2) ((void)(s1)) |
1795 | #endif |
1796 | |
1797 | #ifdef PNG_BENIGN_ERRORS_SUPPORTED |
1798 | /* Benign error in libpng. Can continue, but may have a problem. |
1799 | * User can choose whether to handle as a fatal error or as a warning. */ |
1800 | PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr, |
1801 | png_const_charp warning_message)); |
1802 | |
1803 | #ifdef PNG_READ_SUPPORTED |
1804 | /* Same, chunk name is prepended to message (only during read) */ |
1805 | PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr, |
1806 | png_const_charp warning_message)); |
1807 | #endif |
1808 | |
1809 | PNG_EXPORT(109, void, png_set_benign_errors, |
1810 | (png_structrp png_ptr, int allowed)); |
1811 | #else |
1812 | # ifdef PNG_ALLOW_BENIGN_ERRORS |
1813 | # define png_benign_error png_warning |
1814 | # define png_chunk_benign_error png_chunk_warning |
1815 | # else |
1816 | # define png_benign_error png_error |
1817 | # define png_chunk_benign_error png_chunk_error |
1818 | # endif |
1819 | #endif |
1820 | |
1821 | /* The png_set_<chunk> functions are for storing values in the png_info_struct. |
1822 | * Similarly, the png_get_<chunk> calls are used to read values from the |
1823 | * png_info_struct, either storing the parameters in the passed variables, or |
1824 | * setting pointers into the png_info_struct where the data is stored. The |
1825 | * png_get_<chunk> functions return a non-zero value if the data was available |
1826 | * in info_ptr, or return zero and do not change any of the parameters if the |
1827 | * data was not available. |
1828 | * |
1829 | * These functions should be used instead of directly accessing png_info |
1830 | * to avoid problems with future changes in the size and internal layout of |
1831 | * png_info_struct. |
1832 | */ |
1833 | /* Returns "flag" if chunk data is valid in info_ptr. */ |
1834 | PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr, |
1835 | png_const_inforp info_ptr, png_uint_32 flag)); |
1836 | |
1837 | /* Returns number of bytes needed to hold a transformed row. */ |
1838 | PNG_EXPORT(111, size_t, png_get_rowbytes, (png_const_structrp png_ptr, |
1839 | png_const_inforp info_ptr)); |
1840 | |
1841 | #ifdef PNG_INFO_IMAGE_SUPPORTED |
1842 | /* Returns row_pointers, which is an array of pointers to scanlines that was |
1843 | * returned from png_read_png(). |
1844 | */ |
1845 | PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr, |
1846 | png_const_inforp info_ptr)); |
1847 | |
1848 | /* Set row_pointers, which is an array of pointers to scanlines for use |
1849 | * by png_write_png(). |
1850 | */ |
1851 | PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr, |
1852 | png_inforp info_ptr, png_bytepp row_pointers)); |
1853 | #endif |
1854 | |
1855 | /* Returns number of color channels in image. */ |
1856 | PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr, |
1857 | png_const_inforp info_ptr)); |
1858 | |
1859 | #ifdef PNG_EASY_ACCESS_SUPPORTED |
1860 | /* Returns image width in pixels. */ |
1861 | PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr, |
1862 | png_const_inforp info_ptr)); |
1863 | |
1864 | /* Returns image height in pixels. */ |
1865 | PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr, |
1866 | png_const_inforp info_ptr)); |
1867 | |
1868 | /* Returns image bit_depth. */ |
1869 | PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr, |
1870 | png_const_inforp info_ptr)); |
1871 | |
1872 | /* Returns image color_type. */ |
1873 | PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr, |
1874 | png_const_inforp info_ptr)); |
1875 | |
1876 | /* Returns image filter_type. */ |
1877 | PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr, |
1878 | png_const_inforp info_ptr)); |
1879 | |
1880 | /* Returns image interlace_type. */ |
1881 | PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr, |
1882 | png_const_inforp info_ptr)); |
1883 | |
1884 | /* Returns image compression_type. */ |
1885 | PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr, |
1886 | png_const_inforp info_ptr)); |
1887 | |
1888 | /* Returns image resolution in pixels per meter, from pHYs chunk data. */ |
1889 | PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, |
1890 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
1891 | PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, |
1892 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
1893 | PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, |
1894 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
1895 | |
1896 | /* Returns pixel aspect ratio, computed from pHYs chunk data. */ |
1897 | PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, |
1898 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
1899 | PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, |
1900 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
1901 | |
1902 | /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ |
1903 | PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, |
1904 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
1905 | PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, |
1906 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
1907 | PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, |
1908 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
1909 | PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, |
1910 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
1911 | |
1912 | #endif /* EASY_ACCESS */ |
1913 | |
1914 | #ifdef PNG_READ_SUPPORTED |
1915 | /* Returns pointer to signature string read from PNG header */ |
1916 | PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr, |
1917 | png_const_inforp info_ptr)); |
1918 | #endif |
1919 | |
1920 | #ifdef PNG_bKGD_SUPPORTED |
1921 | PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr, |
1922 | png_inforp info_ptr, png_color_16p *background)); |
1923 | #endif |
1924 | |
1925 | #ifdef PNG_bKGD_SUPPORTED |
1926 | PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr, |
1927 | png_inforp info_ptr, png_const_color_16p background)); |
1928 | #endif |
1929 | |
1930 | #ifdef PNG_cHRM_SUPPORTED |
1931 | PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr, |
1932 | png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x, |
1933 | double *red_y, double *green_x, double *green_y, double *blue_x, |
1934 | double *blue_y)) |
1935 | PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr, |
1936 | png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z, |
1937 | double *green_X, double *green_Y, double *green_Z, double *blue_X, |
1938 | double *blue_Y, double *blue_Z)) |
1939 | PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, |
1940 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
1941 | png_fixed_point *int_white_x, png_fixed_point *int_white_y, |
1942 | png_fixed_point *int_red_x, png_fixed_point *int_red_y, |
1943 | png_fixed_point *int_green_x, png_fixed_point *int_green_y, |
1944 | png_fixed_point *int_blue_x, png_fixed_point *int_blue_y)) |
1945 | PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, |
1946 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
1947 | png_fixed_point *int_red_X, png_fixed_point *int_red_Y, |
1948 | png_fixed_point *int_red_Z, png_fixed_point *int_green_X, |
1949 | png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, |
1950 | png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, |
1951 | png_fixed_point *int_blue_Z)) |
1952 | #endif |
1953 | |
1954 | #ifdef PNG_cHRM_SUPPORTED |
1955 | PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr, |
1956 | png_inforp info_ptr, |
1957 | double white_x, double white_y, double red_x, double red_y, double green_x, |
1958 | double green_y, double blue_x, double blue_y)) |
1959 | PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr, |
1960 | png_inforp info_ptr, double red_X, double red_Y, double red_Z, |
1961 | double green_X, double green_Y, double green_Z, double blue_X, |
1962 | double blue_Y, double blue_Z)) |
1963 | PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr, |
1964 | png_inforp info_ptr, png_fixed_point int_white_x, |
1965 | png_fixed_point int_white_y, png_fixed_point int_red_x, |
1966 | png_fixed_point int_red_y, png_fixed_point int_green_x, |
1967 | png_fixed_point int_green_y, png_fixed_point int_blue_x, |
1968 | png_fixed_point int_blue_y)) |
1969 | PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr, |
1970 | png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, |
1971 | png_fixed_point int_red_Z, png_fixed_point int_green_X, |
1972 | png_fixed_point int_green_Y, png_fixed_point int_green_Z, |
1973 | png_fixed_point int_blue_X, png_fixed_point int_blue_Y, |
1974 | png_fixed_point int_blue_Z)) |
1975 | #endif |
1976 | |
1977 | #ifdef PNG_eXIf_SUPPORTED |
1978 | PNG_EXPORT(246, png_uint_32, png_get_eXIf, (png_const_structrp png_ptr, |
1979 | png_inforp info_ptr, png_bytep *exif)); |
1980 | PNG_EXPORT(247, void, png_set_eXIf, (png_const_structrp png_ptr, |
1981 | png_inforp info_ptr, png_bytep exif)); |
1982 | |
1983 | PNG_EXPORT(248, png_uint_32, png_get_eXIf_1, (png_const_structrp png_ptr, |
1984 | png_const_inforp info_ptr, png_uint_32 *num_exif, png_bytep *exif)); |
1985 | PNG_EXPORT(249, void, png_set_eXIf_1, (png_const_structrp png_ptr, |
1986 | png_inforp info_ptr, png_uint_32 num_exif, png_bytep exif)); |
1987 | #endif |
1988 | |
1989 | #ifdef PNG_gAMA_SUPPORTED |
1990 | PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr, |
1991 | png_const_inforp info_ptr, double *file_gamma)) |
1992 | PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, |
1993 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
1994 | png_fixed_point *int_file_gamma)) |
1995 | #endif |
1996 | |
1997 | #ifdef PNG_gAMA_SUPPORTED |
1998 | PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr, |
1999 | png_inforp info_ptr, double file_gamma)) |
2000 | PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr, |
2001 | png_inforp info_ptr, png_fixed_point int_file_gamma)) |
2002 | #endif |
2003 | |
2004 | #ifdef PNG_hIST_SUPPORTED |
2005 | PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr, |
2006 | png_inforp info_ptr, png_uint_16p *hist)); |
2007 | PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr, |
2008 | png_inforp info_ptr, png_const_uint_16p hist)); |
2009 | #endif |
2010 | |
2011 | PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr, |
2012 | png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, |
2013 | int *bit_depth, int *color_type, int *interlace_method, |
2014 | int *compression_method, int *filter_method)); |
2015 | |
2016 | PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr, |
2017 | png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, |
2018 | int color_type, int interlace_method, int compression_method, |
2019 | int filter_method)); |
2020 | |
2021 | #ifdef PNG_oFFs_SUPPORTED |
2022 | PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr, |
2023 | png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, |
2024 | int *unit_type)); |
2025 | #endif |
2026 | |
2027 | #ifdef PNG_oFFs_SUPPORTED |
2028 | PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr, |
2029 | png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y, |
2030 | int unit_type)); |
2031 | #endif |
2032 | |
2033 | #ifdef PNG_pCAL_SUPPORTED |
2034 | PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr, |
2035 | png_inforp info_ptr, png_charp *purpose, png_int_32 *X0, |
2036 | png_int_32 *X1, int *type, int *nparams, png_charp *units, |
2037 | png_charpp *params)); |
2038 | #endif |
2039 | |
2040 | #ifdef PNG_pCAL_SUPPORTED |
2041 | PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr, |
2042 | png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1, |
2043 | int type, int nparams, png_const_charp units, png_charpp params)); |
2044 | #endif |
2045 | |
2046 | #ifdef PNG_pHYs_SUPPORTED |
2047 | PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr, |
2048 | png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
2049 | int *unit_type)); |
2050 | #endif |
2051 | |
2052 | #ifdef PNG_pHYs_SUPPORTED |
2053 | PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr, |
2054 | png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); |
2055 | #endif |
2056 | |
2057 | PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr, |
2058 | png_inforp info_ptr, png_colorp *palette, int *num_palette)); |
2059 | |
2060 | PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr, |
2061 | png_inforp info_ptr, png_const_colorp palette, int num_palette)); |
2062 | |
2063 | #ifdef PNG_sBIT_SUPPORTED |
2064 | PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr, |
2065 | png_inforp info_ptr, png_color_8p *sig_bit)); |
2066 | #endif |
2067 | |
2068 | #ifdef PNG_sBIT_SUPPORTED |
2069 | PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr, |
2070 | png_inforp info_ptr, png_const_color_8p sig_bit)); |
2071 | #endif |
2072 | |
2073 | #ifdef PNG_sRGB_SUPPORTED |
2074 | PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr, |
2075 | png_const_inforp info_ptr, int *file_srgb_intent)); |
2076 | #endif |
2077 | |
2078 | #ifdef PNG_sRGB_SUPPORTED |
2079 | PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr, |
2080 | png_inforp info_ptr, int srgb_intent)); |
2081 | PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr, |
2082 | png_inforp info_ptr, int srgb_intent)); |
2083 | #endif |
2084 | |
2085 | #ifdef PNG_iCCP_SUPPORTED |
2086 | PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr, |
2087 | png_inforp info_ptr, png_charpp name, int *compression_type, |
2088 | png_bytepp profile, png_uint_32 *proflen)); |
2089 | #endif |
2090 | |
2091 | #ifdef PNG_iCCP_SUPPORTED |
2092 | PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr, |
2093 | png_inforp info_ptr, png_const_charp name, int compression_type, |
2094 | png_const_bytep profile, png_uint_32 proflen)); |
2095 | #endif |
2096 | |
2097 | #ifdef PNG_sPLT_SUPPORTED |
2098 | PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr, |
2099 | png_inforp info_ptr, png_sPLT_tpp entries)); |
2100 | #endif |
2101 | |
2102 | #ifdef PNG_sPLT_SUPPORTED |
2103 | PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr, |
2104 | png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)); |
2105 | #endif |
2106 | |
2107 | #ifdef PNG_TEXT_SUPPORTED |
2108 | /* png_get_text also returns the number of text chunks in *num_text */ |
2109 | PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr, |
2110 | png_inforp info_ptr, png_textp *text_ptr, int *num_text)); |
2111 | #endif |
2112 | |
2113 | /* Note while png_set_text() will accept a structure whose text, |
2114 | * language, and translated keywords are NULL pointers, the structure |
2115 | * returned by png_get_text will always contain regular |
2116 | * zero-terminated C strings. They might be empty strings but |
2117 | * they will never be NULL pointers. |
2118 | */ |
2119 | |
2120 | #ifdef PNG_TEXT_SUPPORTED |
2121 | PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr, |
2122 | png_inforp info_ptr, png_const_textp text_ptr, int num_text)); |
2123 | #endif |
2124 | |
2125 | #ifdef PNG_tIME_SUPPORTED |
2126 | PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr, |
2127 | png_inforp info_ptr, png_timep *mod_time)); |
2128 | #endif |
2129 | |
2130 | #ifdef PNG_tIME_SUPPORTED |
2131 | PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr, |
2132 | png_inforp info_ptr, png_const_timep mod_time)); |
2133 | #endif |
2134 | |
2135 | #ifdef PNG_tRNS_SUPPORTED |
2136 | PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr, |
2137 | png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans, |
2138 | png_color_16p *trans_color)); |
2139 | #endif |
2140 | |
2141 | #ifdef PNG_tRNS_SUPPORTED |
2142 | PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr, |
2143 | png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans, |
2144 | png_const_color_16p trans_color)); |
2145 | #endif |
2146 | |
2147 | #ifdef PNG_sCAL_SUPPORTED |
2148 | PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr, |
2149 | png_const_inforp info_ptr, int *unit, double *width, double *height)) |
2150 | #if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \ |
2151 | defined(PNG_FLOATING_POINT_SUPPORTED) |
2152 | /* NOTE: this API is currently implemented using floating point arithmetic, |
2153 | * consequently it can only be used on systems with floating point support. |
2154 | * In any case the range of values supported by png_fixed_point is small and it |
2155 | * is highly recommended that png_get_sCAL_s be used instead. |
2156 | */ |
2157 | PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, |
2158 | (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, |
2159 | png_fixed_point *width, png_fixed_point *height)) |
2160 | #endif |
2161 | PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, |
2162 | (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, |
2163 | png_charpp swidth, png_charpp sheight)); |
2164 | |
2165 | PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr, |
2166 | png_inforp info_ptr, int unit, double width, double height)) |
2167 | PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr, |
2168 | png_inforp info_ptr, int unit, png_fixed_point width, |
2169 | png_fixed_point height)) |
2170 | PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr, |
2171 | png_inforp info_ptr, int unit, |
2172 | png_const_charp swidth, png_const_charp sheight)); |
2173 | #endif /* sCAL */ |
2174 | |
2175 | #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED |
2176 | /* Provide the default handling for all unknown chunks or, optionally, for |
2177 | * specific unknown chunks. |
2178 | * |
2179 | * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was |
2180 | * ignored and the default was used, the per-chunk setting only had an effect on |
2181 | * write. If you wish to have chunk-specific handling on read in code that must |
2182 | * work on earlier versions you must use a user chunk callback to specify the |
2183 | * desired handling (keep or discard.) |
2184 | * |
2185 | * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The |
2186 | * parameter is interpreted as follows: |
2187 | * |
2188 | * READ: |
2189 | * PNG_HANDLE_CHUNK_AS_DEFAULT: |
2190 | * Known chunks: do normal libpng processing, do not keep the chunk (but |
2191 | * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED) |
2192 | * Unknown chunks: for a specific chunk use the global default, when used |
2193 | * as the default discard the chunk data. |
2194 | * PNG_HANDLE_CHUNK_NEVER: |
2195 | * Discard the chunk data. |
2196 | * PNG_HANDLE_CHUNK_IF_SAFE: |
2197 | * Keep the chunk data if the chunk is not critical else raise a chunk |
2198 | * error. |
2199 | * PNG_HANDLE_CHUNK_ALWAYS: |
2200 | * Keep the chunk data. |
2201 | * |
2202 | * If the chunk data is saved it can be retrieved using png_get_unknown_chunks, |
2203 | * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent |
2204 | * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks |
2205 | * it simply resets the behavior to the libpng default. |
2206 | * |
2207 | * INTERACTION WITH USER CHUNK CALLBACKS: |
2208 | * The per-chunk handling is always used when there is a png_user_chunk_ptr |
2209 | * callback and the callback returns 0; the chunk is then always stored *unless* |
2210 | * it is critical and the per-chunk setting is other than ALWAYS. Notice that |
2211 | * the global default is *not* used in this case. (In effect the per-chunk |
2212 | * value is incremented to at least IF_SAFE.) |
2213 | * |
2214 | * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and |
2215 | * per-chunk defaults will be honored. If you want to preserve the current |
2216 | * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE |
2217 | * as the default - if you don't do this libpng 1.6 will issue a warning. |
2218 | * |
2219 | * If you want unhandled unknown chunks to be discarded in libpng 1.6 and |
2220 | * earlier simply return '1' (handled). |
2221 | * |
2222 | * PNG_HANDLE_AS_UNKNOWN_SUPPORTED: |
2223 | * If this is *not* set known chunks will always be handled by libpng and |
2224 | * will never be stored in the unknown chunk list. Known chunks listed to |
2225 | * png_set_keep_unknown_chunks will have no effect. If it is set then known |
2226 | * chunks listed with a keep other than AS_DEFAULT will *never* be processed |
2227 | * by libpng, in addition critical chunks must either be processed by the |
2228 | * callback or saved. |
2229 | * |
2230 | * The IHDR and IEND chunks must not be listed. Because this turns off the |
2231 | * default handling for chunks that would otherwise be recognized the |
2232 | * behavior of libpng transformations may well become incorrect! |
2233 | * |
2234 | * WRITE: |
2235 | * When writing chunks the options only apply to the chunks specified by |
2236 | * png_set_unknown_chunks (below), libpng will *always* write known chunks |
2237 | * required by png_set_ calls and will always write the core critical chunks |
2238 | * (as required for PLTE). |
2239 | * |
2240 | * Each chunk in the png_set_unknown_chunks list is looked up in the |
2241 | * png_set_keep_unknown_chunks list to find the keep setting, this is then |
2242 | * interpreted as follows: |
2243 | * |
2244 | * PNG_HANDLE_CHUNK_AS_DEFAULT: |
2245 | * Write safe-to-copy chunks and write other chunks if the global |
2246 | * default is set to _ALWAYS, otherwise don't write this chunk. |
2247 | * PNG_HANDLE_CHUNK_NEVER: |
2248 | * Do not write the chunk. |
2249 | * PNG_HANDLE_CHUNK_IF_SAFE: |
2250 | * Write the chunk if it is safe-to-copy, otherwise do not write it. |
2251 | * PNG_HANDLE_CHUNK_ALWAYS: |
2252 | * Write the chunk. |
2253 | * |
2254 | * Note that the default behavior is effectively the opposite of the read case - |
2255 | * in read unknown chunks are not stored by default, in write they are written |
2256 | * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different |
2257 | * - on write the safe-to-copy bit is checked, on read the critical bit is |
2258 | * checked and on read if the chunk is critical an error will be raised. |
2259 | * |
2260 | * num_chunks: |
2261 | * =========== |
2262 | * If num_chunks is positive, then the "keep" parameter specifies the manner |
2263 | * for handling only those chunks appearing in the chunk_list array, |
2264 | * otherwise the chunk list array is ignored. |
2265 | * |
2266 | * If num_chunks is 0 the "keep" parameter specifies the default behavior for |
2267 | * unknown chunks, as described above. |
2268 | * |
2269 | * If num_chunks is negative, then the "keep" parameter specifies the manner |
2270 | * for handling all unknown chunks plus all chunks recognized by libpng |
2271 | * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to |
2272 | * be processed by libpng. |
2273 | */ |
2274 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
2275 | PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr, |
2276 | int keep, png_const_bytep chunk_list, int num_chunks)); |
2277 | #endif /* HANDLE_AS_UNKNOWN */ |
2278 | |
2279 | /* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned; |
2280 | * the result is therefore true (non-zero) if special handling is required, |
2281 | * false for the default handling. |
2282 | */ |
2283 | PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr, |
2284 | png_const_bytep chunk_name)); |
2285 | #endif /* SET_UNKNOWN_CHUNKS */ |
2286 | |
2287 | #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED |
2288 | PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr, |
2289 | png_inforp info_ptr, png_const_unknown_chunkp unknowns, |
2290 | int num_unknowns)); |
2291 | /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added |
2292 | * unknowns to the location currently stored in the png_struct. This is |
2293 | * invariably the wrong value on write. To fix this call the following API |
2294 | * for each chunk in the list with the correct location. If you know your |
2295 | * code won't be compiled on earlier versions you can rely on |
2296 | * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing |
2297 | * the correct thing. |
2298 | */ |
2299 | |
2300 | PNG_EXPORT(175, void, png_set_unknown_chunk_location, |
2301 | (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location)); |
2302 | |
2303 | PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr, |
2304 | png_inforp info_ptr, png_unknown_chunkpp entries)); |
2305 | #endif |
2306 | |
2307 | /* Png_free_data() will turn off the "valid" flag for anything it frees. |
2308 | * If you need to turn it off for a chunk that your application has freed, |
2309 | * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); |
2310 | */ |
2311 | PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr, |
2312 | png_inforp info_ptr, int mask)); |
2313 | |
2314 | #ifdef PNG_INFO_IMAGE_SUPPORTED |
2315 | /* The "params" pointer is currently not used and is for future expansion. */ |
2316 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
2317 | PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr, |
2318 | int transforms, png_voidp params)); |
2319 | #endif |
2320 | #ifdef PNG_WRITE_SUPPORTED |
2321 | PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr, |
2322 | int transforms, png_voidp params)); |
2323 | #endif |
2324 | #endif |
2325 | |
2326 | PNG_EXPORT(180, png_const_charp, png_get_copyright, |
2327 | (png_const_structrp png_ptr)); |
2328 | PNG_EXPORT(181, png_const_charp, , |
2329 | (png_const_structrp png_ptr)); |
2330 | PNG_EXPORT(182, png_const_charp, , |
2331 | (png_const_structrp png_ptr)); |
2332 | PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, |
2333 | (png_const_structrp png_ptr)); |
2334 | |
2335 | #ifdef PNG_MNG_FEATURES_SUPPORTED |
2336 | PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr, |
2337 | png_uint_32 mng_features_permitted)); |
2338 | #endif |
2339 | |
2340 | /* For use in png_set_keep_unknown, added to version 1.2.6 */ |
2341 | #define PNG_HANDLE_CHUNK_AS_DEFAULT 0 |
2342 | #define PNG_HANDLE_CHUNK_NEVER 1 |
2343 | #define PNG_HANDLE_CHUNK_IF_SAFE 2 |
2344 | #define PNG_HANDLE_CHUNK_ALWAYS 3 |
2345 | #define PNG_HANDLE_CHUNK_LAST 4 |
2346 | |
2347 | /* Strip the prepended error numbers ("#nnn ") from error and warning |
2348 | * messages before passing them to the error or warning handler. |
2349 | */ |
2350 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
2351 | PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr, |
2352 | png_uint_32 strip_mode)); |
2353 | #endif |
2354 | |
2355 | /* Added in libpng-1.2.6 */ |
2356 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
2357 | PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr, |
2358 | png_uint_32 user_width_max, png_uint_32 user_height_max)); |
2359 | PNG_EXPORT(187, png_uint_32, png_get_user_width_max, |
2360 | (png_const_structrp png_ptr)); |
2361 | PNG_EXPORT(188, png_uint_32, png_get_user_height_max, |
2362 | (png_const_structrp png_ptr)); |
2363 | /* Added in libpng-1.4.0 */ |
2364 | PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr, |
2365 | png_uint_32 user_chunk_cache_max)); |
2366 | PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, |
2367 | (png_const_structrp png_ptr)); |
2368 | /* Added in libpng-1.4.1 */ |
2369 | PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr, |
2370 | png_alloc_size_t user_chunk_cache_max)); |
2371 | PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, |
2372 | (png_const_structrp png_ptr)); |
2373 | #endif |
2374 | |
2375 | #if defined(PNG_INCH_CONVERSIONS_SUPPORTED) |
2376 | PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, |
2377 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
2378 | |
2379 | PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, |
2380 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
2381 | |
2382 | PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, |
2383 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
2384 | |
2385 | PNG_FP_EXPORT(196, float, png_get_x_offset_inches, |
2386 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
2387 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
2388 | PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, |
2389 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
2390 | #endif |
2391 | |
2392 | PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr, |
2393 | png_const_inforp info_ptr)) |
2394 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
2395 | PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, |
2396 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
2397 | #endif |
2398 | |
2399 | # ifdef PNG_pHYs_SUPPORTED |
2400 | PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr, |
2401 | png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
2402 | int *unit_type)); |
2403 | # endif /* pHYs */ |
2404 | #endif /* INCH_CONVERSIONS */ |
2405 | |
2406 | /* Added in libpng-1.4.0 */ |
2407 | #ifdef PNG_IO_STATE_SUPPORTED |
2408 | PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr)); |
2409 | |
2410 | /* Removed from libpng 1.6; use png_get_io_chunk_type. */ |
2411 | PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr), |
2412 | PNG_DEPRECATED) |
2413 | |
2414 | PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, |
2415 | (png_const_structrp png_ptr)); |
2416 | |
2417 | /* The flags returned by png_get_io_state() are the following: */ |
2418 | # define PNG_IO_NONE 0x0000 /* no I/O at this moment */ |
2419 | # define PNG_IO_READING 0x0001 /* currently reading */ |
2420 | # define PNG_IO_WRITING 0x0002 /* currently writing */ |
2421 | # define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ |
2422 | # define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ |
2423 | # define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ |
2424 | # define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ |
2425 | # define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ |
2426 | # define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ |
2427 | #endif /* IO_STATE */ |
2428 | |
2429 | /* Interlace support. The following macros are always defined so that if |
2430 | * libpng interlace handling is turned off the macros may be used to handle |
2431 | * interlaced images within the application. |
2432 | */ |
2433 | #define PNG_INTERLACE_ADAM7_PASSES 7 |
2434 | |
2435 | /* Two macros to return the first row and first column of the original, |
2436 | * full, image which appears in a given pass. 'pass' is in the range 0 |
2437 | * to 6 and the result is in the range 0 to 7. |
2438 | */ |
2439 | #define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) |
2440 | #define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) |
2441 | |
2442 | /* A macro to return the offset between pixels in the output row for a pair of |
2443 | * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that |
2444 | * follows. Note that ROW_OFFSET is the offset from one row to the next whereas |
2445 | * COL_OFFSET is from one column to the next, within a row. |
2446 | */ |
2447 | #define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) |
2448 | #define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) |
2449 | |
2450 | /* Two macros to help evaluate the number of rows or columns in each |
2451 | * pass. This is expressed as a shift - effectively log2 of the number or |
2452 | * rows or columns in each 8x8 tile of the original image. |
2453 | */ |
2454 | #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) |
2455 | #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) |
2456 | |
2457 | /* Hence two macros to determine the number of rows or columns in a given |
2458 | * pass of an image given its height or width. In fact these macros may |
2459 | * return non-zero even though the sub-image is empty, because the other |
2460 | * dimension may be empty for a small image. |
2461 | */ |
2462 | #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ |
2463 | -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) |
2464 | #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ |
2465 | -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) |
2466 | |
2467 | /* For the reader row callbacks (both progressive and sequential) it is |
2468 | * necessary to find the row in the output image given a row in an interlaced |
2469 | * image, so two more macros: |
2470 | */ |
2471 | #define PNG_ROW_FROM_PASS_ROW(y_in, pass) \ |
2472 | (((y_in)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) |
2473 | #define PNG_COL_FROM_PASS_COL(x_in, pass) \ |
2474 | (((x_in)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) |
2475 | |
2476 | /* Two macros which return a boolean (0 or 1) saying whether the given row |
2477 | * or column is in a particular pass. These use a common utility macro that |
2478 | * returns a mask for a given pass - the offset 'off' selects the row or |
2479 | * column version. The mask has the appropriate bit set for each column in |
2480 | * the tile. |
2481 | */ |
2482 | #define PNG_PASS_MASK(pass,off) ( \ |
2483 | ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \ |
2484 | ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) |
2485 | |
2486 | #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ |
2487 | ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) |
2488 | #define PNG_COL_IN_INTERLACE_PASS(x, pass) \ |
2489 | ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) |
2490 | |
2491 | #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED |
2492 | /* With these routines we avoid an integer divide, which will be slower on |
2493 | * most machines. However, it does take more operations than the corresponding |
2494 | * divide method, so it may be slower on a few RISC systems. There are two |
2495 | * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. |
2496 | * |
2497 | * Note that the rounding factors are NOT supposed to be the same! 128 and |
2498 | * 32768 are correct for the NODIV code; 127 and 32767 are correct for the |
2499 | * standard method. |
2500 | * |
2501 | * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] |
2502 | */ |
2503 | |
2504 | /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ |
2505 | |
2506 | # define png_composite(composite, fg, alpha, bg) \ |
2507 | { \ |
2508 | png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ |
2509 | * (png_uint_16)(alpha) \ |
2510 | + (png_uint_16)(bg)*(png_uint_16)(255 \ |
2511 | - (png_uint_16)(alpha)) + 128); \ |
2512 | (composite) = (png_byte)(((temp + (temp >> 8)) >> 8) & 0xff); \ |
2513 | } |
2514 | |
2515 | # define png_composite_16(composite, fg, alpha, bg) \ |
2516 | { \ |
2517 | png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ |
2518 | * (png_uint_32)(alpha) \ |
2519 | + (png_uint_32)(bg)*(65535 \ |
2520 | - (png_uint_32)(alpha)) + 32768); \ |
2521 | (composite) = (png_uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); \ |
2522 | } |
2523 | |
2524 | #else /* Standard method using integer division */ |
2525 | |
2526 | # define png_composite(composite, fg, alpha, bg) \ |
2527 | (composite) = \ |
2528 | (png_byte)(0xff & (((png_uint_16)(fg) * (png_uint_16)(alpha) + \ |
2529 | (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ |
2530 | 127) / 255)) |
2531 | |
2532 | # define png_composite_16(composite, fg, alpha, bg) \ |
2533 | (composite) = \ |
2534 | (png_uint_16)(0xffff & (((png_uint_32)(fg) * (png_uint_32)(alpha) + \ |
2535 | (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ |
2536 | 32767) / 65535)) |
2537 | #endif /* READ_COMPOSITE_NODIV */ |
2538 | |
2539 | #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED |
2540 | PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); |
2541 | PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); |
2542 | PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); |
2543 | #endif |
2544 | |
2545 | PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr, |
2546 | png_const_bytep buf)); |
2547 | /* No png_get_int_16 -- may be added if there's a real need for it. */ |
2548 | |
2549 | /* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ |
2550 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
2551 | PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); |
2552 | #endif |
2553 | #ifdef PNG_SAVE_INT_32_SUPPORTED |
2554 | PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); |
2555 | #endif |
2556 | |
2557 | /* Place a 16-bit number into a buffer in PNG byte order. |
2558 | * The parameter is declared unsigned int, not png_uint_16, |
2559 | * just to avoid potential problems on pre-ANSI C compilers. |
2560 | */ |
2561 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
2562 | PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); |
2563 | /* No png_save_int_16 -- may be added if there's a real need for it. */ |
2564 | #endif |
2565 | |
2566 | #ifdef PNG_USE_READ_MACROS |
2567 | /* Inline macros to do direct reads of bytes from the input buffer. |
2568 | * The png_get_int_32() routine assumes we are using two's complement |
2569 | * format for negative values, which is almost certainly true. |
2570 | */ |
2571 | # define PNG_get_uint_32(buf) \ |
2572 | (((png_uint_32)(*(buf)) << 24) + \ |
2573 | ((png_uint_32)(*((buf) + 1)) << 16) + \ |
2574 | ((png_uint_32)(*((buf) + 2)) << 8) + \ |
2575 | ((png_uint_32)(*((buf) + 3)))) |
2576 | |
2577 | /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the |
2578 | * function) incorrectly returned a value of type png_uint_32. |
2579 | */ |
2580 | # define PNG_get_uint_16(buf) \ |
2581 | ((png_uint_16) \ |
2582 | (((unsigned int)(*(buf)) << 8) + \ |
2583 | ((unsigned int)(*((buf) + 1))))) |
2584 | |
2585 | # define PNG_get_int_32(buf) \ |
2586 | ((png_int_32)((*(buf) & 0x80) \ |
2587 | ? -((png_int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \ |
2588 | : (png_int_32)png_get_uint_32(buf))) |
2589 | |
2590 | /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h, |
2591 | * but defining a macro name prefixed with PNG_PREFIX. |
2592 | */ |
2593 | # ifndef PNG_PREFIX |
2594 | # define png_get_uint_32(buf) PNG_get_uint_32(buf) |
2595 | # define png_get_uint_16(buf) PNG_get_uint_16(buf) |
2596 | # define png_get_int_32(buf) PNG_get_int_32(buf) |
2597 | # endif |
2598 | #else |
2599 | # ifdef PNG_PREFIX |
2600 | /* No macros; revert to the (redefined) function */ |
2601 | # define PNG_get_uint_32 (png_get_uint_32) |
2602 | # define PNG_get_uint_16 (png_get_uint_16) |
2603 | # define PNG_get_int_32 (png_get_int_32) |
2604 | # endif |
2605 | #endif |
2606 | |
2607 | #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED |
2608 | PNG_EXPORT(242, void, png_set_check_for_invalid_index, |
2609 | (png_structrp png_ptr, int allowed)); |
2610 | # ifdef PNG_GET_PALETTE_MAX_SUPPORTED |
2611 | PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr, |
2612 | png_const_infop info_ptr)); |
2613 | # endif |
2614 | #endif /* CHECK_FOR_INVALID_INDEX */ |
2615 | |
2616 | /******************************************************************************* |
2617 | * Section 5: SIMPLIFIED API |
2618 | ******************************************************************************* |
2619 | * |
2620 | * Please read the documentation in libpng-manual.txt (TODO: write said |
2621 | * documentation) if you don't understand what follows. |
2622 | * |
2623 | * The simplified API hides the details of both libpng and the PNG file format |
2624 | * itself. It allows PNG files to be read into a very limited number of |
2625 | * in-memory bitmap formats or to be written from the same formats. If these |
2626 | * formats do not accommodate your needs then you can, and should, use the more |
2627 | * sophisticated APIs above - these support a wide variety of in-memory formats |
2628 | * and a wide variety of sophisticated transformations to those formats as well |
2629 | * as a wide variety of APIs to manipulate ancillary information. |
2630 | * |
2631 | * To read a PNG file using the simplified API: |
2632 | * |
2633 | * 1) Declare a 'png_image' structure (see below) on the stack, set the |
2634 | * version field to PNG_IMAGE_VERSION and the 'opaque' pointer to NULL |
2635 | * (this is REQUIRED, your program may crash if you don't do it.) |
2636 | * 2) Call the appropriate png_image_begin_read... function. |
2637 | * 3) Set the png_image 'format' member to the required sample format. |
2638 | * 4) Allocate a buffer for the image and, if required, the color-map. |
2639 | * 5) Call png_image_finish_read to read the image and, if required, the |
2640 | * color-map into your buffers. |
2641 | * |
2642 | * There are no restrictions on the format of the PNG input itself; all valid |
2643 | * color types, bit depths, and interlace methods are acceptable, and the |
2644 | * input image is transformed as necessary to the requested in-memory format |
2645 | * during the png_image_finish_read() step. The only caveat is that if you |
2646 | * request a color-mapped image from a PNG that is full-color or makes |
2647 | * complex use of an alpha channel the transformation is extremely lossy and the |
2648 | * result may look terrible. |
2649 | * |
2650 | * To write a PNG file using the simplified API: |
2651 | * |
2652 | * 1) Declare a 'png_image' structure on the stack and memset() it to all zero. |
2653 | * 2) Initialize the members of the structure that describe the image, setting |
2654 | * the 'format' member to the format of the image samples. |
2655 | * 3) Call the appropriate png_image_write... function with a pointer to the |
2656 | * image and, if necessary, the color-map to write the PNG data. |
2657 | * |
2658 | * png_image is a structure that describes the in-memory format of an image |
2659 | * when it is being read or defines the in-memory format of an image that you |
2660 | * need to write: |
2661 | */ |
2662 | #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) || \ |
2663 | defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) |
2664 | |
2665 | #define PNG_IMAGE_VERSION 1 |
2666 | |
2667 | typedef struct png_control *png_controlp; |
2668 | typedef struct |
2669 | { |
2670 | png_controlp opaque; /* Initialize to NULL, free with png_image_free */ |
2671 | png_uint_32 version; /* Set to PNG_IMAGE_VERSION */ |
2672 | png_uint_32 width; /* Image width in pixels (columns) */ |
2673 | png_uint_32 height; /* Image height in pixels (rows) */ |
2674 | png_uint_32 format; /* Image format as defined below */ |
2675 | png_uint_32 flags; /* A bit mask containing informational flags */ |
2676 | png_uint_32 colormap_entries; |
2677 | /* Number of entries in the color-map */ |
2678 | |
2679 | /* In the event of an error or warning the following field will be set to a |
2680 | * non-zero value and the 'message' field will contain a '\0' terminated |
2681 | * string with the libpng error or warning message. If both warnings and |
2682 | * an error were encountered, only the error is recorded. If there |
2683 | * are multiple warnings, only the first one is recorded. |
2684 | * |
2685 | * The upper 30 bits of this value are reserved, the low two bits contain |
2686 | * a value as follows: |
2687 | */ |
2688 | # define PNG_IMAGE_WARNING 1 |
2689 | # define PNG_IMAGE_ERROR 2 |
2690 | /* |
2691 | * The result is a two-bit code such that a value more than 1 indicates |
2692 | * a failure in the API just called: |
2693 | * |
2694 | * 0 - no warning or error |
2695 | * 1 - warning |
2696 | * 2 - error |
2697 | * 3 - error preceded by warning |
2698 | */ |
2699 | # define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1) |
2700 | |
2701 | png_uint_32 warning_or_error; |
2702 | |
2703 | char message[64]; |
2704 | } png_image, *png_imagep; |
2705 | |
2706 | /* The samples of the image have one to four channels whose components have |
2707 | * original values in the range 0 to 1.0: |
2708 | * |
2709 | * 1: A single gray or luminance channel (G). |
2710 | * 2: A gray/luminance channel and an alpha channel (GA). |
2711 | * 3: Three red, green, blue color channels (RGB). |
2712 | * 4: Three color channels and an alpha channel (RGBA). |
2713 | * |
2714 | * The components are encoded in one of two ways: |
2715 | * |
2716 | * a) As a small integer, value 0..255, contained in a single byte. For the |
2717 | * alpha channel the original value is simply value/255. For the color or |
2718 | * luminance channels the value is encoded according to the sRGB specification |
2719 | * and matches the 8-bit format expected by typical display devices. |
2720 | * |
2721 | * The color/gray channels are not scaled (pre-multiplied) by the alpha |
2722 | * channel and are suitable for passing to color management software. |
2723 | * |
2724 | * b) As a value in the range 0..65535, contained in a 2-byte integer. All |
2725 | * channels can be converted to the original value by dividing by 65535; all |
2726 | * channels are linear. Color channels use the RGB encoding (RGB end-points) of |
2727 | * the sRGB specification. This encoding is identified by the |
2728 | * PNG_FORMAT_FLAG_LINEAR flag below. |
2729 | * |
2730 | * When the simplified API needs to convert between sRGB and linear colorspaces, |
2731 | * the actual sRGB transfer curve defined in the sRGB specification (see the |
2732 | * article at <https://en.wikipedia.org/wiki/SRGB>) is used, not the gamma=1/2.2 |
2733 | * approximation used elsewhere in libpng. |
2734 | * |
2735 | * When an alpha channel is present it is expected to denote pixel coverage |
2736 | * of the color or luminance channels and is returned as an associated alpha |
2737 | * channel: the color/gray channels are scaled (pre-multiplied) by the alpha |
2738 | * value. |
2739 | * |
2740 | * The samples are either contained directly in the image data, between 1 and 8 |
2741 | * bytes per pixel according to the encoding, or are held in a color-map indexed |
2742 | * by bytes in the image data. In the case of a color-map the color-map entries |
2743 | * are individual samples, encoded as above, and the image data has one byte per |
2744 | * pixel to select the relevant sample from the color-map. |
2745 | */ |
2746 | |
2747 | /* PNG_FORMAT_* |
2748 | * |
2749 | * #defines to be used in png_image::format. Each #define identifies a |
2750 | * particular layout of sample data and, if present, alpha values. There are |
2751 | * separate defines for each of the two component encodings. |
2752 | * |
2753 | * A format is built up using single bit flag values. All combinations are |
2754 | * valid. Formats can be built up from the flag values or you can use one of |
2755 | * the predefined values below. When testing formats always use the FORMAT_FLAG |
2756 | * macros to test for individual features - future versions of the library may |
2757 | * add new flags. |
2758 | * |
2759 | * When reading or writing color-mapped images the format should be set to the |
2760 | * format of the entries in the color-map then png_image_{read,write}_colormap |
2761 | * called to read or write the color-map and set the format correctly for the |
2762 | * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly! |
2763 | * |
2764 | * NOTE: libpng can be built with particular features disabled. If you see |
2765 | * compiler errors because the definition of one of the following flags has been |
2766 | * compiled out it is because libpng does not have the required support. It is |
2767 | * possible, however, for the libpng configuration to enable the format on just |
2768 | * read or just write; in that case you may see an error at run time. You can |
2769 | * guard against this by checking for the definition of the appropriate |
2770 | * "_SUPPORTED" macro, one of: |
2771 | * |
2772 | * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED |
2773 | */ |
2774 | #define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */ |
2775 | #define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */ |
2776 | #define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2-byte channels else 1-byte */ |
2777 | #define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */ |
2778 | |
2779 | #ifdef PNG_FORMAT_BGR_SUPPORTED |
2780 | # define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */ |
2781 | #endif |
2782 | |
2783 | #ifdef PNG_FORMAT_AFIRST_SUPPORTED |
2784 | # define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */ |
2785 | #endif |
2786 | |
2787 | #define PNG_FORMAT_FLAG_ASSOCIATED_ALPHA 0x40U /* alpha channel is associated */ |
2788 | |
2789 | /* Commonly used formats have predefined macros. |
2790 | * |
2791 | * First the single byte (sRGB) formats: |
2792 | */ |
2793 | #define PNG_FORMAT_GRAY 0 |
2794 | #define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA |
2795 | #define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST) |
2796 | #define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR |
2797 | #define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR) |
2798 | #define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA) |
2799 | #define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST) |
2800 | #define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA) |
2801 | #define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST) |
2802 | |
2803 | /* Then the linear 2-byte formats. When naming these "Y" is used to |
2804 | * indicate a luminance (gray) channel. |
2805 | */ |
2806 | #define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR |
2807 | #define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA) |
2808 | #define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR) |
2809 | #define PNG_FORMAT_LINEAR_RGB_ALPHA \ |
2810 | (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA) |
2811 | |
2812 | /* With color-mapped formats the image data is one byte for each pixel, the byte |
2813 | * is an index into the color-map which is formatted as above. To obtain a |
2814 | * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP |
2815 | * to one of the above definitions, or you can use one of the definitions below. |
2816 | */ |
2817 | #define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP) |
2818 | #define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP) |
2819 | #define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP) |
2820 | #define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP) |
2821 | #define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP) |
2822 | #define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP) |
2823 | |
2824 | /* PNG_IMAGE macros |
2825 | * |
2826 | * These are convenience macros to derive information from a png_image |
2827 | * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the |
2828 | * actual image sample values - either the entries in the color-map or the |
2829 | * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values |
2830 | * for the pixels and will always return 1 for color-mapped formats. The |
2831 | * remaining macros return information about the rows in the image and the |
2832 | * complete image. |
2833 | * |
2834 | * NOTE: All the macros that take a png_image::format parameter are compile time |
2835 | * constants if the format parameter is, itself, a constant. Therefore these |
2836 | * macros can be used in array declarations and case labels where required. |
2837 | * Similarly the macros are also pre-processor constants (sizeof is not used) so |
2838 | * they can be used in #if tests. |
2839 | * |
2840 | * First the information about the samples. |
2841 | */ |
2842 | #define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\ |
2843 | (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1) |
2844 | /* Return the total number of channels in a given format: 1..4 */ |
2845 | |
2846 | #define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\ |
2847 | ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1) |
2848 | /* Return the size in bytes of a single component of a pixel or color-map |
2849 | * entry (as appropriate) in the image: 1 or 2. |
2850 | */ |
2851 | |
2852 | #define PNG_IMAGE_SAMPLE_SIZE(fmt)\ |
2853 | (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)) |
2854 | /* This is the size of the sample data for one sample. If the image is |
2855 | * color-mapped it is the size of one color-map entry (and image pixels are |
2856 | * one byte in size), otherwise it is the size of one image pixel. |
2857 | */ |
2858 | |
2859 | #define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\ |
2860 | (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256) |
2861 | /* The maximum size of the color-map required by the format expressed in a |
2862 | * count of components. This can be used to compile-time allocate a |
2863 | * color-map: |
2864 | * |
2865 | * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)]; |
2866 | * |
2867 | * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)]; |
2868 | * |
2869 | * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the |
2870 | * information from one of the png_image_begin_read_ APIs and dynamically |
2871 | * allocate the required memory. |
2872 | */ |
2873 | |
2874 | /* Corresponding information about the pixels */ |
2875 | #define PNG_IMAGE_PIXEL_(test,fmt)\ |
2876 | (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt)) |
2877 | |
2878 | #define PNG_IMAGE_PIXEL_CHANNELS(fmt)\ |
2879 | PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt) |
2880 | /* The number of separate channels (components) in a pixel; 1 for a |
2881 | * color-mapped image. |
2882 | */ |
2883 | |
2884 | #define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\ |
2885 | PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt) |
2886 | /* The size, in bytes, of each component in a pixel; 1 for a color-mapped |
2887 | * image. |
2888 | */ |
2889 | |
2890 | #define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt) |
2891 | /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */ |
2892 | |
2893 | /* Information about the whole row, or whole image */ |
2894 | #define PNG_IMAGE_ROW_STRIDE(image)\ |
2895 | (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width) |
2896 | /* Return the total number of components in a single row of the image; this |
2897 | * is the minimum 'row stride', the minimum count of components between each |
2898 | * row. For a color-mapped image this is the minimum number of bytes in a |
2899 | * row. |
2900 | * |
2901 | * WARNING: this macro overflows for some images with more than one component |
2902 | * and very large image widths. libpng will refuse to process an image where |
2903 | * this macro would overflow. |
2904 | */ |
2905 | |
2906 | #define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\ |
2907 | (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride)) |
2908 | /* Return the size, in bytes, of an image buffer given a png_image and a row |
2909 | * stride - the number of components to leave space for in each row. |
2910 | * |
2911 | * WARNING: this macro overflows a 32-bit integer for some large PNG images, |
2912 | * libpng will refuse to process an image where such an overflow would occur. |
2913 | */ |
2914 | |
2915 | #define PNG_IMAGE_SIZE(image)\ |
2916 | PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image)) |
2917 | /* Return the size, in bytes, of the image in memory given just a png_image; |
2918 | * the row stride is the minimum stride required for the image. |
2919 | */ |
2920 | |
2921 | #define PNG_IMAGE_COLORMAP_SIZE(image)\ |
2922 | (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries) |
2923 | /* Return the size, in bytes, of the color-map of this image. If the image |
2924 | * format is not a color-map format this will return a size sufficient for |
2925 | * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if |
2926 | * you don't want to allocate a color-map in this case. |
2927 | */ |
2928 | |
2929 | /* PNG_IMAGE_FLAG_* |
2930 | * |
2931 | * Flags containing additional information about the image are held in the |
2932 | * 'flags' field of png_image. |
2933 | */ |
2934 | #define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01 |
2935 | /* This indicates that the RGB values of the in-memory bitmap do not |
2936 | * correspond to the red, green and blue end-points defined by sRGB. |
2937 | */ |
2938 | |
2939 | #define PNG_IMAGE_FLAG_FAST 0x02 |
2940 | /* On write emphasise speed over compression; the resultant PNG file will be |
2941 | * larger but will be produced significantly faster, particular for large |
2942 | * images. Do not use this option for images which will be distributed, only |
2943 | * used it when producing intermediate files that will be read back in |
2944 | * repeatedly. For a typical 24-bit image the option will double the read |
2945 | * speed at the cost of increasing the image size by 25%, however for many |
2946 | * more compressible images the PNG file can be 10 times larger with only a |
2947 | * slight speed gain. |
2948 | */ |
2949 | |
2950 | #define PNG_IMAGE_FLAG_16BIT_sRGB 0x04 |
2951 | /* On read if the image is a 16-bit per component image and there is no gAMA |
2952 | * or sRGB chunk assume that the components are sRGB encoded. Notice that |
2953 | * images output by the simplified API always have gamma information; setting |
2954 | * this flag only affects the interpretation of 16-bit images from an |
2955 | * external source. It is recommended that the application expose this flag |
2956 | * to the user; the user can normally easily recognize the difference between |
2957 | * linear and sRGB encoding. This flag has no effect on write - the data |
2958 | * passed to the write APIs must have the correct encoding (as defined |
2959 | * above.) |
2960 | * |
2961 | * If the flag is not set (the default) input 16-bit per component data is |
2962 | * assumed to be linear. |
2963 | * |
2964 | * NOTE: the flag can only be set after the png_image_begin_read_ call, |
2965 | * because that call initializes the 'flags' field. |
2966 | */ |
2967 | |
2968 | #ifdef PNG_SIMPLIFIED_READ_SUPPORTED |
2969 | /* READ APIs |
2970 | * --------- |
2971 | * |
2972 | * The png_image passed to the read APIs must have been initialized by setting |
2973 | * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.) |
2974 | */ |
2975 | #ifdef PNG_STDIO_SUPPORTED |
2976 | PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image, |
2977 | const char *file_name)); |
2978 | /* The named file is opened for read and the image header is filled in |
2979 | * from the PNG header in the file. |
2980 | */ |
2981 | |
2982 | PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image, |
2983 | FILE* file)); |
2984 | /* The PNG header is read from the stdio FILE object. */ |
2985 | #endif /* STDIO */ |
2986 | |
2987 | PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image, |
2988 | png_const_voidp memory, size_t size)); |
2989 | /* The PNG header is read from the given memory buffer. */ |
2990 | |
2991 | PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image, |
2992 | png_const_colorp background, void *buffer, png_int_32 row_stride, |
2993 | void *colormap)); |
2994 | /* Finish reading the image into the supplied buffer and clean up the |
2995 | * png_image structure. |
2996 | * |
2997 | * row_stride is the step, in byte or 2-byte units as appropriate, |
2998 | * between adjacent rows. A positive stride indicates that the top-most row |
2999 | * is first in the buffer - the normal top-down arrangement. A negative |
3000 | * stride indicates that the bottom-most row is first in the buffer. |
3001 | * |
3002 | * background need only be supplied if an alpha channel must be removed from |
3003 | * a png_byte format and the removal is to be done by compositing on a solid |
3004 | * color; otherwise it may be NULL and any composition will be done directly |
3005 | * onto the buffer. The value is an sRGB color to use for the background, |
3006 | * for grayscale output the green channel is used. |
3007 | * |
3008 | * background must be supplied when an alpha channel must be removed from a |
3009 | * single byte color-mapped output format, in other words if: |
3010 | * |
3011 | * 1) The original format from png_image_begin_read_from_* had |
3012 | * PNG_FORMAT_FLAG_ALPHA set. |
3013 | * 2) The format set by the application does not. |
3014 | * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and |
3015 | * PNG_FORMAT_FLAG_LINEAR *not* set. |
3016 | * |
3017 | * For linear output removing the alpha channel is always done by compositing |
3018 | * on black and background is ignored. |
3019 | * |
3020 | * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must |
3021 | * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE. |
3022 | * image->colormap_entries will be updated to the actual number of entries |
3023 | * written to the colormap; this may be less than the original value. |
3024 | */ |
3025 | |
3026 | PNG_EXPORT(238, void, png_image_free, (png_imagep image)); |
3027 | /* Free any data allocated by libpng in image->opaque, setting the pointer to |
3028 | * NULL. May be called at any time after the structure is initialized. |
3029 | */ |
3030 | #endif /* SIMPLIFIED_READ */ |
3031 | |
3032 | #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED |
3033 | /* WRITE APIS |
3034 | * ---------- |
3035 | * For write you must initialize a png_image structure to describe the image to |
3036 | * be written. To do this use memset to set the whole structure to 0 then |
3037 | * initialize fields describing your image. |
3038 | * |
3039 | * version: must be set to PNG_IMAGE_VERSION |
3040 | * opaque: must be initialized to NULL |
3041 | * width: image width in pixels |
3042 | * height: image height in rows |
3043 | * format: the format of the data (image and color-map) you wish to write |
3044 | * flags: set to 0 unless one of the defined flags applies; set |
3045 | * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB |
3046 | * values do not correspond to the colors in sRGB. |
3047 | * colormap_entries: set to the number of entries in the color-map (0 to 256) |
3048 | */ |
3049 | #ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED |
3050 | PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image, |
3051 | const char *file, int convert_to_8bit, const void *buffer, |
3052 | png_int_32 row_stride, const void *colormap)); |
3053 | /* Write the image to the named file. */ |
3054 | |
3055 | PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file, |
3056 | int convert_to_8_bit, const void *buffer, png_int_32 row_stride, |
3057 | const void *colormap)); |
3058 | /* Write the image to the given (FILE*). */ |
3059 | #endif /* SIMPLIFIED_WRITE_STDIO */ |
3060 | |
3061 | /* With all write APIs if image is in one of the linear formats with 16-bit |
3062 | * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG |
3063 | * gamma encoded according to the sRGB specification, otherwise a 16-bit linear |
3064 | * encoded PNG file is written. |
3065 | * |
3066 | * With color-mapped data formats the colormap parameter point to a color-map |
3067 | * with at least image->colormap_entries encoded in the specified format. If |
3068 | * the format is linear the written PNG color-map will be converted to sRGB |
3069 | * regardless of the convert_to_8_bit flag. |
3070 | * |
3071 | * With all APIs row_stride is handled as in the read APIs - it is the spacing |
3072 | * from one row to the next in component sized units (1 or 2 bytes) and if |
3073 | * negative indicates a bottom-up row layout in the buffer. If row_stride is |
3074 | * zero, libpng will calculate it for you from the image width and number of |
3075 | * channels. |
3076 | * |
3077 | * Note that the write API does not support interlacing, sub-8-bit pixels or |
3078 | * most ancillary chunks. If you need to write text chunks (e.g. for copyright |
3079 | * notices) you need to use one of the other APIs. |
3080 | */ |
3081 | |
3082 | PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory, |
3083 | png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8_bit, |
3084 | const void *buffer, png_int_32 row_stride, const void *colormap)); |
3085 | /* Write the image to the given memory buffer. The function both writes the |
3086 | * whole PNG data stream to *memory and updates *memory_bytes with the count |
3087 | * of bytes written. |
3088 | * |
3089 | * 'memory' may be NULL. In this case *memory_bytes is not read however on |
3090 | * success the number of bytes which would have been written will still be |
3091 | * stored in *memory_bytes. On failure *memory_bytes will contain 0. |
3092 | * |
3093 | * If 'memory' is not NULL it must point to memory[*memory_bytes] of |
3094 | * writeable memory. |
3095 | * |
3096 | * If the function returns success memory[*memory_bytes] (if 'memory' is not |
3097 | * NULL) contains the written PNG data. *memory_bytes will always be less |
3098 | * than or equal to the original value. |
3099 | * |
3100 | * If the function returns false and *memory_bytes was not changed an error |
3101 | * occurred during write. If *memory_bytes was changed, or is not 0 if |
3102 | * 'memory' was NULL, the write would have succeeded but for the memory |
3103 | * buffer being too small. *memory_bytes contains the required number of |
3104 | * bytes and will be bigger that the original value. |
3105 | */ |
3106 | |
3107 | #define png_image_write_get_memory_size(image, size, convert_to_8_bit, buffer,\ |
3108 | row_stride, colormap)\ |
3109 | png_image_write_to_memory(&(image), 0, &(size), convert_to_8_bit, buffer,\ |
3110 | row_stride, colormap) |
3111 | /* Return the amount of memory in 'size' required to compress this image. |
3112 | * The png_image structure 'image' must be filled in as in the above |
3113 | * function and must not be changed before the actual write call, the buffer |
3114 | * and all other parameters must also be identical to that in the final |
3115 | * write call. The 'size' variable need not be initialized. |
3116 | * |
3117 | * NOTE: the macro returns true/false, if false is returned 'size' will be |
3118 | * set to zero and the write failed and probably will fail if tried again. |
3119 | */ |
3120 | |
3121 | /* You can pre-allocate the buffer by making sure it is of sufficient size |
3122 | * regardless of the amount of compression achieved. The buffer size will |
3123 | * always be bigger than the original image and it will never be filled. The |
3124 | * following macros are provided to assist in allocating the buffer. |
3125 | */ |
3126 | #define PNG_IMAGE_DATA_SIZE(image) (PNG_IMAGE_SIZE(image)+(image).height) |
3127 | /* The number of uncompressed bytes in the PNG byte encoding of the image; |
3128 | * uncompressing the PNG IDAT data will give this number of bytes. |
3129 | * |
3130 | * NOTE: while PNG_IMAGE_SIZE cannot overflow for an image in memory this |
3131 | * macro can because of the extra bytes used in the PNG byte encoding. You |
3132 | * need to avoid this macro if your image size approaches 2^30 in width or |
3133 | * height. The same goes for the remainder of these macros; they all produce |
3134 | * bigger numbers than the actual in-memory image size. |
3135 | */ |
3136 | #ifndef PNG_ZLIB_MAX_SIZE |
3137 | # define PNG_ZLIB_MAX_SIZE(b) ((b)+(((b)+7U)>>3)+(((b)+63U)>>6)+11U) |
3138 | /* An upper bound on the number of compressed bytes given 'b' uncompressed |
3139 | * bytes. This is based on deflateBounds() in zlib; different |
3140 | * implementations of zlib compression may conceivably produce more data so |
3141 | * if your zlib implementation is not zlib itself redefine this macro |
3142 | * appropriately. |
3143 | */ |
3144 | #endif |
3145 | |
3146 | #define PNG_IMAGE_COMPRESSED_SIZE_MAX(image)\ |
3147 | PNG_ZLIB_MAX_SIZE((png_alloc_size_t)PNG_IMAGE_DATA_SIZE(image)) |
3148 | /* An upper bound on the size of the data in the PNG IDAT chunks. */ |
3149 | |
3150 | #define PNG_IMAGE_PNG_SIZE_MAX_(image, image_size)\ |
3151 | ((8U/*sig*/+25U/*IHDR*/+16U/*gAMA*/+44U/*cHRM*/+12U/*IEND*/+\ |
3152 | (((image).format&PNG_FORMAT_FLAG_COLORMAP)?/*colormap: PLTE, tRNS*/\ |
3153 | 12U+3U*(image).colormap_entries/*PLTE data*/+\ |
3154 | (((image).format&PNG_FORMAT_FLAG_ALPHA)?\ |
3155 | 12U/*tRNS*/+(image).colormap_entries:0U):0U)+\ |
3156 | 12U)+(12U*((image_size)/PNG_ZBUF_SIZE))/*IDAT*/+(image_size)) |
3157 | /* A helper for the following macro; if your compiler cannot handle the |
3158 | * following macro use this one with the result of |
3159 | * PNG_IMAGE_COMPRESSED_SIZE_MAX(image) as the second argument (most |
3160 | * compilers should handle this just fine.) |
3161 | */ |
3162 | |
3163 | #define PNG_IMAGE_PNG_SIZE_MAX(image)\ |
3164 | PNG_IMAGE_PNG_SIZE_MAX_(image, PNG_IMAGE_COMPRESSED_SIZE_MAX(image)) |
3165 | /* An upper bound on the total length of the PNG data stream for 'image'. |
3166 | * The result is of type png_alloc_size_t, on 32-bit systems this may |
3167 | * overflow even though PNG_IMAGE_DATA_SIZE does not overflow; the write will |
3168 | * run out of buffer space but return a corrected size which should work. |
3169 | */ |
3170 | #endif /* SIMPLIFIED_WRITE */ |
3171 | /******************************************************************************* |
3172 | * END OF SIMPLIFIED API |
3173 | ******************************************************************************/ |
3174 | #endif /* SIMPLIFIED_{READ|WRITE} */ |
3175 | |
3176 | /******************************************************************************* |
3177 | * Section 6: IMPLEMENTATION OPTIONS |
3178 | ******************************************************************************* |
3179 | * |
3180 | * Support for arbitrary implementation-specific optimizations. The API allows |
3181 | * particular options to be turned on or off. 'Option' is the number of the |
3182 | * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given |
3183 | * by the PNG_OPTION_ defines below. |
3184 | * |
3185 | * HARDWARE: normally hardware capabilities, such as the Intel SSE instructions, |
3186 | * are detected at run time, however sometimes it may be impossible |
3187 | * to do this in user mode, in which case it is necessary to discover |
3188 | * the capabilities in an OS specific way. Such capabilities are |
3189 | * listed here when libpng has support for them and must be turned |
3190 | * ON by the application if present. |
3191 | * |
3192 | * SOFTWARE: sometimes software optimizations actually result in performance |
3193 | * decrease on some architectures or systems, or with some sets of |
3194 | * PNG images. 'Software' options allow such optimizations to be |
3195 | * selected at run time. |
3196 | */ |
3197 | #ifdef PNG_SET_OPTION_SUPPORTED |
3198 | #ifdef PNG_ARM_NEON_API_SUPPORTED |
3199 | # define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */ |
3200 | #endif |
3201 | #define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */ |
3202 | #define PNG_SKIP_sRGB_CHECK_PROFILE 4 /* SOFTWARE: Check ICC profile for sRGB */ |
3203 | #ifdef PNG_MIPS_MSA_API_SUPPORTED |
3204 | # define PNG_MIPS_MSA 6 /* HARDWARE: MIPS Msa SIMD instructions supported */ |
3205 | #endif |
3206 | #ifdef PNG_DISABLE_ADLER32_CHECK_SUPPORTED |
3207 | # define PNG_IGNORE_ADLER32 8 /* SOFTWARE: disable Adler32 check on IDAT */ |
3208 | #endif |
3209 | #ifdef PNG_POWERPC_VSX_API_SUPPORTED |
3210 | # define PNG_POWERPC_VSX 10 /* HARDWARE: PowerPC VSX SIMD instructions |
3211 | * supported */ |
3212 | #endif |
3213 | #ifdef PNG_MIPS_MMI_API_SUPPORTED |
3214 | # define PNG_MIPS_MMI 12 /* HARDWARE: MIPS MMI SIMD instructions supported */ |
3215 | #endif |
3216 | |
3217 | #define PNG_OPTION_NEXT 14 /* Next option - numbers must be even */ |
3218 | |
3219 | /* Return values: NOTE: there are four values and 'off' is *not* zero */ |
3220 | #define PNG_OPTION_UNSET 0 /* Unset - defaults to off */ |
3221 | #define PNG_OPTION_INVALID 1 /* Option number out of range */ |
3222 | #define PNG_OPTION_OFF 2 |
3223 | #define PNG_OPTION_ON 3 |
3224 | |
3225 | PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option, |
3226 | int onoff)); |
3227 | #endif /* SET_OPTION */ |
3228 | |
3229 | /******************************************************************************* |
3230 | * END OF HARDWARE AND SOFTWARE OPTIONS |
3231 | ******************************************************************************/ |
3232 | |
3233 | /* Maintainer: Put new public prototypes here ^, in libpng.3, in project |
3234 | * defs, and in scripts/symbols.def. |
3235 | */ |
3236 | |
3237 | /* The last ordinal number (this is the *last* one already used; the next |
3238 | * one to use is one more than this.) |
3239 | */ |
3240 | #ifdef PNG_EXPORT_LAST_ORDINAL |
3241 | PNG_EXPORT_LAST_ORDINAL(249); |
3242 | #endif |
3243 | |
3244 | #ifdef __cplusplus |
3245 | } |
3246 | #endif |
3247 | |
3248 | #endif /* PNG_VERSION_INFO_ONLY */ |
3249 | /* Do not put anything past this line */ |
3250 | #endif /* PNG_H */ |
3251 | |