|
1 /* |
|
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
|
3 * |
|
4 * This code is free software; you can redistribute it and/or modify it |
|
5 * under the terms of the GNU General Public License version 2 only, as |
|
6 * published by the Free Software Foundation. Oracle designates this |
|
7 * particular file as subject to the "Classpath" exception as provided |
|
8 * by Oracle in the LICENSE file that accompanied this code. |
|
9 * |
|
10 * This code is distributed in the hope that it will be useful, but WITHOUT |
|
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
|
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
|
13 * version 2 for more details (a copy is included in the LICENSE file that |
|
14 * accompanied this code). |
|
15 * |
|
16 * You should have received a copy of the GNU General Public License version |
|
17 * 2 along with this work; if not, write to the Free Software Foundation, |
|
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
|
19 * |
|
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
21 * or visit www.oracle.com if you need additional information or have any |
|
22 * questions. |
|
23 */ |
|
24 |
|
25 /* png.h - header file for PNG reference library |
|
26 * |
|
27 * This file is available under and governed by the GNU General Public |
|
28 * License version 2 only, as published by the Free Software Foundation. |
|
29 * However, the following notice accompanied the original version of this |
|
30 * file and, per its terms, should not be removed: |
|
31 * |
|
32 * libpng version 1.5.4 - July 7, 2011 |
|
33 * Copyright (c) 1998-2011 Glenn Randers-Pehrson |
|
34 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
|
35 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
|
36 * |
|
37 * This code is released under the libpng license (See LICENSE, below) |
|
38 * |
|
39 * Authors and maintainers: |
|
40 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat |
|
41 * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger |
|
42 * libpng versions 0.97, January 1998, through 1.5.4 - July 7, 2011: Glenn |
|
43 * See also "Contributing Authors", below. |
|
44 * |
|
45 * Note about libpng version numbers: |
|
46 * |
|
47 * Due to various miscommunications, unforeseen code incompatibilities |
|
48 * and occasional factors outside the authors' control, version numbering |
|
49 * on the library has not always been consistent and straightforward. |
|
50 * The following table summarizes matters since version 0.89c, which was |
|
51 * the first widely used release: |
|
52 * |
|
53 * source png.h png.h shared-lib |
|
54 * version string int version |
|
55 * ------- ------ ----- ---------- |
|
56 * 0.89c "1.0 beta 3" 0.89 89 1.0.89 |
|
57 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] |
|
58 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] |
|
59 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] |
|
60 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] |
|
61 * 0.97c 0.97 97 2.0.97 |
|
62 * 0.98 0.98 98 2.0.98 |
|
63 * 0.99 0.99 98 2.0.99 |
|
64 * 0.99a-m 0.99 99 2.0.99 |
|
65 * 1.00 1.00 100 2.1.0 [100 should be 10000] |
|
66 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] |
|
67 * 1.0.1 png.h string is 10001 2.1.0 |
|
68 * 1.0.1a-e identical to the 10002 from here on, the shared library |
|
69 * 1.0.2 source version) 10002 is 2.V where V is the source code |
|
70 * 1.0.2a-b 10003 version, except as noted. |
|
71 * 1.0.3 10003 |
|
72 * 1.0.3a-d 10004 |
|
73 * 1.0.4 10004 |
|
74 * 1.0.4a-f 10005 |
|
75 * 1.0.5 (+ 2 patches) 10005 |
|
76 * 1.0.5a-d 10006 |
|
77 * 1.0.5e-r 10100 (not source compatible) |
|
78 * 1.0.5s-v 10006 (not binary compatible) |
|
79 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) |
|
80 * 1.0.6d-f 10007 (still binary incompatible) |
|
81 * 1.0.6g 10007 |
|
82 * 1.0.6h 10007 10.6h (testing xy.z so-numbering) |
|
83 * 1.0.6i 10007 10.6i |
|
84 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) |
|
85 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) |
|
86 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) |
|
87 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) |
|
88 * 1.0.7 1 10007 (still compatible) |
|
89 * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4 |
|
90 * 1.0.8rc1 1 10008 2.1.0.8rc1 |
|
91 * 1.0.8 1 10008 2.1.0.8 |
|
92 * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6 |
|
93 * 1.0.9rc1 1 10009 2.1.0.9rc1 |
|
94 * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10 |
|
95 * 1.0.9rc2 1 10009 2.1.0.9rc2 |
|
96 * 1.0.9 1 10009 2.1.0.9 |
|
97 * 1.0.10beta1 1 10010 2.1.0.10beta1 |
|
98 * 1.0.10rc1 1 10010 2.1.0.10rc1 |
|
99 * 1.0.10 1 10010 2.1.0.10 |
|
100 * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3 |
|
101 * 1.0.11rc1 1 10011 2.1.0.11rc1 |
|
102 * 1.0.11 1 10011 2.1.0.11 |
|
103 * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2 |
|
104 * 1.0.12rc1 2 10012 2.1.0.12rc1 |
|
105 * 1.0.12 2 10012 2.1.0.12 |
|
106 * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned) |
|
107 * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2 |
|
108 * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5 |
|
109 * 1.2.0rc1 3 10200 3.1.2.0rc1 |
|
110 * 1.2.0 3 10200 3.1.2.0 |
|
111 * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4 |
|
112 * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2 |
|
113 * 1.2.1 3 10201 3.1.2.1 |
|
114 * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6 |
|
115 * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1 |
|
116 * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1 |
|
117 * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1 |
|
118 * 1.0.13 10 10013 10.so.0.1.0.13 |
|
119 * 1.2.2 12 10202 12.so.0.1.2.2 |
|
120 * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6 |
|
121 * 1.2.3 12 10203 12.so.0.1.2.3 |
|
122 * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3 |
|
123 * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1 |
|
124 * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1 |
|
125 * 1.0.14 10 10014 10.so.0.1.0.14 |
|
126 * 1.2.4 13 10204 12.so.0.1.2.4 |
|
127 * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2 |
|
128 * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3 |
|
129 * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3 |
|
130 * 1.0.15 10 10015 10.so.0.1.0.15 |
|
131 * 1.2.5 13 10205 12.so.0.1.2.5 |
|
132 * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4 |
|
133 * 1.0.16 10 10016 10.so.0.1.0.16 |
|
134 * 1.2.6 13 10206 12.so.0.1.2.6 |
|
135 * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2 |
|
136 * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1 |
|
137 * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1 |
|
138 * 1.0.17 10 10017 12.so.0.1.0.17 |
|
139 * 1.2.7 13 10207 12.so.0.1.2.7 |
|
140 * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5 |
|
141 * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5 |
|
142 * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5 |
|
143 * 1.0.18 10 10018 12.so.0.1.0.18 |
|
144 * 1.2.8 13 10208 12.so.0.1.2.8 |
|
145 * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3 |
|
146 * 1.2.9beta4-11 13 10209 12.so.0.9[.0] |
|
147 * 1.2.9rc1 13 10209 12.so.0.9[.0] |
|
148 * 1.2.9 13 10209 12.so.0.9[.0] |
|
149 * 1.2.10beta1-7 13 10210 12.so.0.10[.0] |
|
150 * 1.2.10rc1-2 13 10210 12.so.0.10[.0] |
|
151 * 1.2.10 13 10210 12.so.0.10[.0] |
|
152 * 1.4.0beta1-5 14 10400 14.so.0.0[.0] |
|
153 * 1.2.11beta1-4 13 10211 12.so.0.11[.0] |
|
154 * 1.4.0beta7-8 14 10400 14.so.0.0[.0] |
|
155 * 1.2.11 13 10211 12.so.0.11[.0] |
|
156 * 1.2.12 13 10212 12.so.0.12[.0] |
|
157 * 1.4.0beta9-14 14 10400 14.so.0.0[.0] |
|
158 * 1.2.13 13 10213 12.so.0.13[.0] |
|
159 * 1.4.0beta15-36 14 10400 14.so.0.0[.0] |
|
160 * 1.4.0beta37-87 14 10400 14.so.14.0[.0] |
|
161 * 1.4.0rc01 14 10400 14.so.14.0[.0] |
|
162 * 1.4.0beta88-109 14 10400 14.so.14.0[.0] |
|
163 * 1.4.0rc02-08 14 10400 14.so.14.0[.0] |
|
164 * 1.4.0 14 10400 14.so.14.0[.0] |
|
165 * 1.4.1beta01-03 14 10401 14.so.14.1[.0] |
|
166 * 1.4.1rc01 14 10401 14.so.14.1[.0] |
|
167 * 1.4.1beta04-12 14 10401 14.so.14.1[.0] |
|
168 * 1.4.1 14 10401 14.so.14.1[.0] |
|
169 * 1.4.2 14 10402 14.so.14.2[.0] |
|
170 * 1.4.3 14 10403 14.so.14.3[.0] |
|
171 * 1.4.4 14 10404 14.so.14.4[.0] |
|
172 * 1.5.0beta01-58 15 10500 15.so.15.0[.0] |
|
173 * 1.5.0rc01-07 15 10500 15.so.15.0[.0] |
|
174 * 1.5.0 15 10500 15.so.15.0[.0] |
|
175 * 1.5.1beta01-11 15 10501 15.so.15.1[.0] |
|
176 * 1.5.1rc01-02 15 10501 15.so.15.1[.0] |
|
177 * 1.5.1 15 10501 15.so.15.1[.0] |
|
178 * 1.5.2beta01-03 15 10502 15.so.15.2[.0] |
|
179 * 1.5.2rc01-03 15 10502 15.so.15.2[.0] |
|
180 * 1.5.2 15 10502 15.so.15.2[.0] |
|
181 * 1.5.3beta01-10 15 10503 15.so.15.3[.0] |
|
182 * 1.5.3rc01-02 15 10503 15.so.15.3[.0] |
|
183 * 1.5.3beta11 15 10503 15.so.15.3[.0] |
|
184 * 1.5.3 [omitted] |
|
185 * 1.5.4beta01-08 15 10504 15.so.15.4[.0] |
|
186 * 1.5.4rc01 15 10504 15.so.15.4[.0] |
|
187 * 1.5.4 15 10504 15.so.15.4[.0] |
|
188 * |
|
189 * Henceforth the source version will match the shared-library major |
|
190 * and minor numbers; the shared-library major version number will be |
|
191 * used for changes in backward compatibility, as it is intended. The |
|
192 * PNG_LIBPNG_VER macro, which is not used within libpng but is available |
|
193 * for applications, is an unsigned integer of the form xyyzz corresponding |
|
194 * to the source version x.y.z (leading zeros in y and z). Beta versions |
|
195 * were given the previous public release number plus a letter, until |
|
196 * version 1.0.6j; from then on they were given the upcoming public |
|
197 * release number plus "betaNN" or "rcN". |
|
198 * |
|
199 * Binary incompatibility exists only when applications make direct access |
|
200 * to the info_ptr or png_ptr members through png.h, and the compiled |
|
201 * application is loaded with a different version of the library. |
|
202 * |
|
203 * DLLNUM will change each time there are forward or backward changes |
|
204 * in binary compatibility (e.g., when a new feature is added). |
|
205 * |
|
206 * See libpng-manual.txt or libpng.3 for more information. The PNG |
|
207 * specification is available as a W3C Recommendation and as an ISO |
|
208 * Specification, <http://www.w3.org/TR/2003/REC-PNG-20031110/ |
|
209 */ |
|
210 |
|
211 /* |
|
212 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE: |
|
213 * |
|
214 * If you modify libpng you may insert additional notices immediately following |
|
215 * this sentence. |
|
216 * |
|
217 * This code is released under the libpng license. |
|
218 * |
|
219 * libpng versions 1.2.6, August 15, 2004, through 1.5.4, July 7, 2011, are |
|
220 * Copyright (c) 2004, 2006-2011 Glenn Randers-Pehrson, and are |
|
221 * distributed according to the same disclaimer and license as libpng-1.2.5 |
|
222 * with the following individual added to the list of Contributing Authors: |
|
223 * |
|
224 * Cosmin Truta |
|
225 * |
|
226 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are |
|
227 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are |
|
228 * distributed according to the same disclaimer and license as libpng-1.0.6 |
|
229 * with the following individuals added to the list of Contributing Authors: |
|
230 * |
|
231 * Simon-Pierre Cadieux |
|
232 * Eric S. Raymond |
|
233 * Gilles Vollant |
|
234 * |
|
235 * and with the following additions to the disclaimer: |
|
236 * |
|
237 * There is no warranty against interference with your enjoyment of the |
|
238 * library or against infringement. There is no warranty that our |
|
239 * efforts or the library will fulfill any of your particular purposes |
|
240 * or needs. This library is provided with all faults, and the entire |
|
241 * risk of satisfactory quality, performance, accuracy, and effort is with |
|
242 * the user. |
|
243 * |
|
244 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are |
|
245 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are |
|
246 * distributed according to the same disclaimer and license as libpng-0.96, |
|
247 * with the following individuals added to the list of Contributing Authors: |
|
248 * |
|
249 * Tom Lane |
|
250 * Glenn Randers-Pehrson |
|
251 * Willem van Schaik |
|
252 * |
|
253 * libpng versions 0.89, June 1996, through 0.96, May 1997, are |
|
254 * Copyright (c) 1996, 1997 Andreas Dilger |
|
255 * Distributed according to the same disclaimer and license as libpng-0.88, |
|
256 * with the following individuals added to the list of Contributing Authors: |
|
257 * |
|
258 * John Bowler |
|
259 * Kevin Bracey |
|
260 * Sam Bushell |
|
261 * Magnus Holmgren |
|
262 * Greg Roelofs |
|
263 * Tom Tanner |
|
264 * |
|
265 * libpng versions 0.5, May 1995, through 0.88, January 1996, are |
|
266 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. |
|
267 * |
|
268 * For the purposes of this copyright and license, "Contributing Authors" |
|
269 * is defined as the following set of individuals: |
|
270 * |
|
271 * Andreas Dilger |
|
272 * Dave Martindale |
|
273 * Guy Eric Schalnat |
|
274 * Paul Schmidt |
|
275 * Tim Wegner |
|
276 * |
|
277 * The PNG Reference Library is supplied "AS IS". The Contributing Authors |
|
278 * and Group 42, Inc. disclaim all warranties, expressed or implied, |
|
279 * including, without limitation, the warranties of merchantability and of |
|
280 * fitness for any purpose. The Contributing Authors and Group 42, Inc. |
|
281 * assume no liability for direct, indirect, incidental, special, exemplary, |
|
282 * or consequential damages, which may result from the use of the PNG |
|
283 * Reference Library, even if advised of the possibility of such damage. |
|
284 * |
|
285 * Permission is hereby granted to use, copy, modify, and distribute this |
|
286 * source code, or portions hereof, for any purpose, without fee, subject |
|
287 * to the following restrictions: |
|
288 * |
|
289 * 1. The origin of this source code must not be misrepresented. |
|
290 * |
|
291 * 2. Altered versions must be plainly marked as such and must not |
|
292 * be misrepresented as being the original source. |
|
293 * |
|
294 * 3. This Copyright notice may not be removed or altered from |
|
295 * any source or altered source distribution. |
|
296 * |
|
297 * The Contributing Authors and Group 42, Inc. specifically permit, without |
|
298 * fee, and encourage the use of this source code as a component to |
|
299 * supporting the PNG file format in commercial products. If you use this |
|
300 * source code in a product, acknowledgment is not required but would be |
|
301 * appreciated. |
|
302 */ |
|
303 |
|
304 /* |
|
305 * A "png_get_copyright" function is available, for convenient use in "about" |
|
306 * boxes and the like: |
|
307 * |
|
308 * printf("%s", png_get_copyright(NULL)); |
|
309 * |
|
310 * Also, the PNG logo (in PNG format, of course) is supplied in the |
|
311 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). |
|
312 */ |
|
313 |
|
314 /* |
|
315 * Libpng is OSI Certified Open Source Software. OSI Certified is a |
|
316 * certification mark of the Open Source Initiative. |
|
317 */ |
|
318 |
|
319 /* |
|
320 * The contributing authors would like to thank all those who helped |
|
321 * with testing, bug fixes, and patience. This wouldn't have been |
|
322 * possible without all of you. |
|
323 * |
|
324 * Thanks to Frank J. T. Wojcik for helping with the documentation. |
|
325 */ |
|
326 |
|
327 /* |
|
328 * Y2K compliance in libpng: |
|
329 * ========================= |
|
330 * |
|
331 * July 7, 2011 |
|
332 * |
|
333 * Since the PNG Development group is an ad-hoc body, we can't make |
|
334 * an official declaration. |
|
335 * |
|
336 * This is your unofficial assurance that libpng from version 0.71 and |
|
337 * upward through 1.5.4 are Y2K compliant. It is my belief that |
|
338 * earlier versions were also Y2K compliant. |
|
339 * |
|
340 * Libpng only has two year fields. One is a 2-byte unsigned integer |
|
341 * that will hold years up to 65535. The other holds the date in text |
|
342 * format, and will hold years up to 9999. |
|
343 * |
|
344 * The integer is |
|
345 * "png_uint_16 year" in png_time_struct. |
|
346 * |
|
347 * The string is |
|
348 * "png_char time_buffer" in png_struct |
|
349 * |
|
350 * There are seven time-related functions: |
|
351 * png.c: png_convert_to_rfc_1123() in png.c |
|
352 * (formerly png_convert_to_rfc_1152() in error) |
|
353 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c |
|
354 * png_convert_from_time_t() in pngwrite.c |
|
355 * png_get_tIME() in pngget.c |
|
356 * png_handle_tIME() in pngrutil.c, called in pngread.c |
|
357 * png_set_tIME() in pngset.c |
|
358 * png_write_tIME() in pngwutil.c, called in pngwrite.c |
|
359 * |
|
360 * All handle dates properly in a Y2K environment. The |
|
361 * png_convert_from_time_t() function calls gmtime() to convert from system |
|
362 * clock time, which returns (year - 1900), which we properly convert to |
|
363 * the full 4-digit year. There is a possibility that applications using |
|
364 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123() |
|
365 * function, or that they are incorrectly passing only a 2-digit year |
|
366 * instead of "year - 1900" into the png_convert_from_struct_tm() function, |
|
367 * but this is not under our control. The libpng documentation has always |
|
368 * stated that it works with 4-digit years, and the APIs have been |
|
369 * documented as such. |
|
370 * |
|
371 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned |
|
372 * integer to hold the year, and can hold years as large as 65535. |
|
373 * |
|
374 * zlib, upon which libpng depends, is also Y2K compliant. It contains |
|
375 * no date-related code. |
|
376 * |
|
377 * Glenn Randers-Pehrson |
|
378 * libpng maintainer |
|
379 * PNG Development Group |
|
380 */ |
|
381 |
|
382 #ifndef PNG_H |
|
383 #define PNG_H |
|
384 |
|
385 /* This is not the place to learn how to use libpng. The file libpng-manual.txt |
|
386 * describes how to use libpng, and the file example.c summarizes it |
|
387 * with some code on which to build. This file is useful for looking |
|
388 * at the actual function definitions and structure components. |
|
389 */ |
|
390 |
|
391 /* Version information for png.h - this should match the version in png.c */ |
|
392 #define PNG_LIBPNG_VER_STRING "1.5.4" |
|
393 #define PNG_HEADER_VERSION_STRING \ |
|
394 " libpng version 1.5.4 - July 7, 2011\n" |
|
395 |
|
396 #define PNG_LIBPNG_VER_SONUM 15 |
|
397 #define PNG_LIBPNG_VER_DLLNUM 15 |
|
398 |
|
399 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */ |
|
400 #define PNG_LIBPNG_VER_MAJOR 1 |
|
401 #define PNG_LIBPNG_VER_MINOR 5 |
|
402 #define PNG_LIBPNG_VER_RELEASE 4 |
|
403 /* This should match the numeric part of the final component of |
|
404 * PNG_LIBPNG_VER_STRING, omitting any leading zero: |
|
405 */ |
|
406 |
|
407 #define PNG_LIBPNG_VER_BUILD 0 |
|
408 |
|
409 /* Release Status */ |
|
410 #define PNG_LIBPNG_BUILD_ALPHA 1 |
|
411 #define PNG_LIBPNG_BUILD_BETA 2 |
|
412 #define PNG_LIBPNG_BUILD_RC 3 |
|
413 #define PNG_LIBPNG_BUILD_STABLE 4 |
|
414 #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 |
|
415 |
|
416 /* Release-Specific Flags */ |
|
417 #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with |
|
418 PNG_LIBPNG_BUILD_STABLE only */ |
|
419 #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with |
|
420 PNG_LIBPNG_BUILD_SPECIAL */ |
|
421 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with |
|
422 PNG_LIBPNG_BUILD_PRIVATE */ |
|
423 |
|
424 #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_BETA |
|
425 |
|
426 /* Careful here. At one time, Guy wanted to use 082, but that would be octal. |
|
427 * We must not include leading zeros. |
|
428 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only |
|
429 * version 1.0.0 was mis-numbered 100 instead of 10000). From |
|
430 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release |
|
431 */ |
|
432 #define PNG_LIBPNG_VER 10504 /* 1.5.4 */ |
|
433 |
|
434 /* Library configuration: these options cannot be changed after |
|
435 * the library has been built. |
|
436 */ |
|
437 #ifndef PNGLCONF_H |
|
438 /* If pnglibconf.h is missing, you can |
|
439 * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h |
|
440 */ |
|
441 # include "pnglibconf.h" |
|
442 #endif |
|
443 |
|
444 #ifndef PNG_VERSION_INFO_ONLY |
|
445 # ifndef PNG_BUILDING_SYMBOL_TABLE |
|
446 /* |
|
447 * Standard header files (not needed for the version info or while |
|
448 * building symbol table -- see scripts/pnglibconf.dfa) |
|
449 */ |
|
450 # ifdef PNG_SETJMP_SUPPORTED |
|
451 # include <setjmp.h> |
|
452 # endif |
|
453 |
|
454 /* Need the time information for converting tIME chunks, it |
|
455 * defines struct tm: |
|
456 */ |
|
457 # ifdef PNG_CONVERT_tIME_SUPPORTED |
|
458 /* "time.h" functions are not supported on all operating systems */ |
|
459 # include <time.h> |
|
460 # endif |
|
461 # endif |
|
462 |
|
463 /* Machine specific configuration. */ |
|
464 # include "pngconf.h" |
|
465 #endif |
|
466 |
|
467 /* |
|
468 * Added at libpng-1.2.8 |
|
469 * |
|
470 * Ref MSDN: Private as priority over Special |
|
471 * VS_FF_PRIVATEBUILD File *was not* built using standard release |
|
472 * procedures. If this value is given, the StringFileInfo block must |
|
473 * contain a PrivateBuild string. |
|
474 * |
|
475 * VS_FF_SPECIALBUILD File *was* built by the original company using |
|
476 * standard release procedures but is a variation of the standard |
|
477 * file of the same version number. If this value is given, the |
|
478 * StringFileInfo block must contain a SpecialBuild string. |
|
479 */ |
|
480 |
|
481 #ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */ |
|
482 # define PNG_LIBPNG_BUILD_TYPE \ |
|
483 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) |
|
484 #else |
|
485 # ifdef PNG_LIBPNG_SPECIALBUILD |
|
486 # define PNG_LIBPNG_BUILD_TYPE \ |
|
487 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) |
|
488 # else |
|
489 # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) |
|
490 # endif |
|
491 #endif |
|
492 |
|
493 #ifndef PNG_VERSION_INFO_ONLY |
|
494 |
|
495 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */ |
|
496 #ifdef __cplusplus |
|
497 extern "C" { |
|
498 #endif /* __cplusplus */ |
|
499 |
|
500 /* Version information for C files, stored in png.c. This had better match |
|
501 * the version above. |
|
502 */ |
|
503 #define png_libpng_ver png_get_header_ver(NULL) |
|
504 |
|
505 /* This file is arranged in several sections: |
|
506 * |
|
507 * 1. Any configuration options that can be specified by for the application |
|
508 * code when it is built. (Build time configuration is in pnglibconf.h) |
|
509 * 2. Type definitions (base types are defined in pngconf.h), structure |
|
510 * definitions. |
|
511 * 3. Exported library functions. |
|
512 * |
|
513 * The library source code has additional files (principally pngpriv.h) that |
|
514 * allow configuration of the library. |
|
515 */ |
|
516 /* Section 1: run time configuration |
|
517 * See pnglibconf.h for build time configuration |
|
518 * |
|
519 * Run time configuration allows the application to choose between |
|
520 * implementations of certain arithmetic APIs. The default is set |
|
521 * at build time and recorded in pnglibconf.h, but it is safe to |
|
522 * override these (and only these) settings. Note that this won't |
|
523 * change what the library does, only application code, and the |
|
524 * settings can (and probably should) be made on a per-file basis |
|
525 * by setting the #defines before including png.h |
|
526 * |
|
527 * Use macros to read integers from PNG data or use the exported |
|
528 * functions? |
|
529 * PNG_USE_READ_MACROS: use the macros (see below) Note that |
|
530 * the macros evaluate their argument multiple times. |
|
531 * PNG_NO_USE_READ_MACROS: call the relevant library function. |
|
532 * |
|
533 * Use the alternative algorithm for compositing alpha samples that |
|
534 * does not use division? |
|
535 * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' |
|
536 * algorithm. |
|
537 * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. |
|
538 * |
|
539 * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is |
|
540 * false? |
|
541 * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error |
|
542 * APIs to png_warning. |
|
543 * Otherwise the calls are mapped to png_error. |
|
544 */ |
|
545 |
|
546 /* Section 2: type definitions, including structures and compile time |
|
547 * constants. |
|
548 * See pngconf.h for base types that vary by machine/system |
|
549 */ |
|
550 |
|
551 /* This triggers a compiler error in png.c, if png.c and png.h |
|
552 * do not agree upon the version number. |
|
553 */ |
|
554 typedef char* png_libpng_version_1_5_4; |
|
555 |
|
556 /* Three color definitions. The order of the red, green, and blue, (and the |
|
557 * exact size) is not important, although the size of the fields need to |
|
558 * be png_byte or png_uint_16 (as defined below). |
|
559 */ |
|
560 typedef struct png_color_struct |
|
561 { |
|
562 png_byte red; |
|
563 png_byte green; |
|
564 png_byte blue; |
|
565 } png_color; |
|
566 typedef png_color FAR * png_colorp; |
|
567 typedef PNG_CONST png_color FAR * png_const_colorp; |
|
568 typedef png_color FAR * FAR * png_colorpp; |
|
569 |
|
570 typedef struct png_color_16_struct |
|
571 { |
|
572 png_byte index; /* used for palette files */ |
|
573 png_uint_16 red; /* for use in red green blue files */ |
|
574 png_uint_16 green; |
|
575 png_uint_16 blue; |
|
576 png_uint_16 gray; /* for use in grayscale files */ |
|
577 } png_color_16; |
|
578 typedef png_color_16 FAR * png_color_16p; |
|
579 typedef PNG_CONST png_color_16 FAR * png_const_color_16p; |
|
580 typedef png_color_16 FAR * FAR * png_color_16pp; |
|
581 |
|
582 typedef struct png_color_8_struct |
|
583 { |
|
584 png_byte red; /* for use in red green blue files */ |
|
585 png_byte green; |
|
586 png_byte blue; |
|
587 png_byte gray; /* for use in grayscale files */ |
|
588 png_byte alpha; /* for alpha channel files */ |
|
589 } png_color_8; |
|
590 typedef png_color_8 FAR * png_color_8p; |
|
591 typedef PNG_CONST png_color_8 FAR * png_const_color_8p; |
|
592 typedef png_color_8 FAR * FAR * png_color_8pp; |
|
593 |
|
594 /* |
|
595 * The following two structures are used for the in-core representation |
|
596 * of sPLT chunks. |
|
597 */ |
|
598 typedef struct png_sPLT_entry_struct |
|
599 { |
|
600 png_uint_16 red; |
|
601 png_uint_16 green; |
|
602 png_uint_16 blue; |
|
603 png_uint_16 alpha; |
|
604 png_uint_16 frequency; |
|
605 } png_sPLT_entry; |
|
606 typedef png_sPLT_entry FAR * png_sPLT_entryp; |
|
607 typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp; |
|
608 typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp; |
|
609 |
|
610 /* When the depth of the sPLT palette is 8 bits, the color and alpha samples |
|
611 * occupy the LSB of their respective members, and the MSB of each member |
|
612 * is zero-filled. The frequency member always occupies the full 16 bits. |
|
613 */ |
|
614 |
|
615 typedef struct png_sPLT_struct |
|
616 { |
|
617 png_charp name; /* palette name */ |
|
618 png_byte depth; /* depth of palette samples */ |
|
619 png_sPLT_entryp entries; /* palette entries */ |
|
620 png_int_32 nentries; /* number of palette entries */ |
|
621 } png_sPLT_t; |
|
622 typedef png_sPLT_t FAR * png_sPLT_tp; |
|
623 typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp; |
|
624 typedef png_sPLT_t FAR * FAR * png_sPLT_tpp; |
|
625 |
|
626 #ifdef PNG_TEXT_SUPPORTED |
|
627 /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, |
|
628 * and whether that contents is compressed or not. The "key" field |
|
629 * points to a regular zero-terminated C string. The "text", "lang", and |
|
630 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers. |
|
631 * However, the structure returned by png_get_text() will always contain |
|
632 * regular zero-terminated C strings (possibly empty), never NULL pointers, |
|
633 * so they can be safely used in printf() and other string-handling functions. |
|
634 */ |
|
635 typedef struct png_text_struct |
|
636 { |
|
637 int compression; /* compression value: |
|
638 -1: tEXt, none |
|
639 0: zTXt, deflate |
|
640 1: iTXt, none |
|
641 2: iTXt, deflate */ |
|
642 png_charp key; /* keyword, 1-79 character description of "text" */ |
|
643 png_charp text; /* comment, may be an empty string (ie "") |
|
644 or a NULL pointer */ |
|
645 png_size_t text_length; /* length of the text string */ |
|
646 png_size_t itxt_length; /* length of the itxt string */ |
|
647 png_charp lang; /* language code, 0-79 characters |
|
648 or a NULL pointer */ |
|
649 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more |
|
650 chars or a NULL pointer */ |
|
651 } png_text; |
|
652 typedef png_text FAR * png_textp; |
|
653 typedef PNG_CONST png_text FAR * png_const_textp; |
|
654 typedef png_text FAR * FAR * png_textpp; |
|
655 #endif |
|
656 |
|
657 /* Supported compression types for text in PNG files (tEXt, and zTXt). |
|
658 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ |
|
659 #define PNG_TEXT_COMPRESSION_NONE_WR -3 |
|
660 #define PNG_TEXT_COMPRESSION_zTXt_WR -2 |
|
661 #define PNG_TEXT_COMPRESSION_NONE -1 |
|
662 #define PNG_TEXT_COMPRESSION_zTXt 0 |
|
663 #define PNG_ITXT_COMPRESSION_NONE 1 |
|
664 #define PNG_ITXT_COMPRESSION_zTXt 2 |
|
665 #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ |
|
666 |
|
667 /* png_time is a way to hold the time in an machine independent way. |
|
668 * Two conversions are provided, both from time_t and struct tm. There |
|
669 * is no portable way to convert to either of these structures, as far |
|
670 * as I know. If you know of a portable way, send it to me. As a side |
|
671 * note - PNG has always been Year 2000 compliant! |
|
672 */ |
|
673 typedef struct png_time_struct |
|
674 { |
|
675 png_uint_16 year; /* full year, as in, 1995 */ |
|
676 png_byte month; /* month of year, 1 - 12 */ |
|
677 png_byte day; /* day of month, 1 - 31 */ |
|
678 png_byte hour; /* hour of day, 0 - 23 */ |
|
679 png_byte minute; /* minute of hour, 0 - 59 */ |
|
680 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ |
|
681 } png_time; |
|
682 typedef png_time FAR * png_timep; |
|
683 typedef PNG_CONST png_time FAR * png_const_timep; |
|
684 typedef png_time FAR * FAR * png_timepp; |
|
685 |
|
686 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \ |
|
687 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED) |
|
688 /* png_unknown_chunk is a structure to hold queued chunks for which there is |
|
689 * no specific support. The idea is that we can use this to queue |
|
690 * up private chunks for output even though the library doesn't actually |
|
691 * know about their semantics. |
|
692 */ |
|
693 typedef struct png_unknown_chunk_t |
|
694 { |
|
695 png_byte name[5]; |
|
696 png_byte *data; |
|
697 png_size_t size; |
|
698 |
|
699 /* libpng-using applications should NOT directly modify this byte. */ |
|
700 png_byte location; /* mode of operation at read time */ |
|
701 } |
|
702 |
|
703 |
|
704 png_unknown_chunk; |
|
705 typedef png_unknown_chunk FAR * png_unknown_chunkp; |
|
706 typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp; |
|
707 typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp; |
|
708 #endif |
|
709 |
|
710 /* Values for the unknown chunk location byte */ |
|
711 |
|
712 #define PNG_HAVE_IHDR 0x01 |
|
713 #define PNG_HAVE_PLTE 0x02 |
|
714 #define PNG_AFTER_IDAT 0x08 |
|
715 |
|
716 /* The complete definition of png_info has, as of libpng-1.5.0, |
|
717 * been moved into a separate header file that is not accessible to |
|
718 * applications. Read libpng-manual.txt or libpng.3 for more info. |
|
719 */ |
|
720 typedef struct png_info_def png_info; |
|
721 typedef png_info FAR * png_infop; |
|
722 typedef PNG_CONST png_info FAR * png_const_infop; |
|
723 typedef png_info FAR * FAR * png_infopp; |
|
724 |
|
725 /* Maximum positive integer used in PNG is (2^31)-1 */ |
|
726 #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) |
|
727 #define PNG_UINT_32_MAX ((png_uint_32)(-1)) |
|
728 #define PNG_SIZE_MAX ((png_size_t)(-1)) |
|
729 |
|
730 /* These are constants for fixed point values encoded in the |
|
731 * PNG specification manner (x100000) |
|
732 */ |
|
733 #define PNG_FP_1 100000 |
|
734 #define PNG_FP_HALF 50000 |
|
735 #define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) |
|
736 #define PNG_FP_MIN (-PNG_FP_MAX) |
|
737 |
|
738 /* These describe the color_type field in png_info. */ |
|
739 /* color type masks */ |
|
740 #define PNG_COLOR_MASK_PALETTE 1 |
|
741 #define PNG_COLOR_MASK_COLOR 2 |
|
742 #define PNG_COLOR_MASK_ALPHA 4 |
|
743 |
|
744 /* color types. Note that not all combinations are legal */ |
|
745 #define PNG_COLOR_TYPE_GRAY 0 |
|
746 #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) |
|
747 #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) |
|
748 #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) |
|
749 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) |
|
750 /* aliases */ |
|
751 #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA |
|
752 #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA |
|
753 |
|
754 /* This is for compression type. PNG 1.0-1.2 only define the single type. */ |
|
755 #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ |
|
756 #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE |
|
757 |
|
758 /* This is for filter type. PNG 1.0-1.2 only define the single type. */ |
|
759 #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ |
|
760 #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ |
|
761 #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE |
|
762 |
|
763 /* These are for the interlacing type. These values should NOT be changed. */ |
|
764 #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ |
|
765 #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ |
|
766 #define PNG_INTERLACE_LAST 2 /* Not a valid value */ |
|
767 |
|
768 /* These are for the oFFs chunk. These values should NOT be changed. */ |
|
769 #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ |
|
770 #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ |
|
771 #define PNG_OFFSET_LAST 2 /* Not a valid value */ |
|
772 |
|
773 /* These are for the pCAL chunk. These values should NOT be changed. */ |
|
774 #define PNG_EQUATION_LINEAR 0 /* Linear transformation */ |
|
775 #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ |
|
776 #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ |
|
777 #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ |
|
778 #define PNG_EQUATION_LAST 4 /* Not a valid value */ |
|
779 |
|
780 /* These are for the sCAL chunk. These values should NOT be changed. */ |
|
781 #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ |
|
782 #define PNG_SCALE_METER 1 /* meters per pixel */ |
|
783 #define PNG_SCALE_RADIAN 2 /* radians per pixel */ |
|
784 #define PNG_SCALE_LAST 3 /* Not a valid value */ |
|
785 |
|
786 /* These are for the pHYs chunk. These values should NOT be changed. */ |
|
787 #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ |
|
788 #define PNG_RESOLUTION_METER 1 /* pixels/meter */ |
|
789 #define PNG_RESOLUTION_LAST 2 /* Not a valid value */ |
|
790 |
|
791 /* These are for the sRGB chunk. These values should NOT be changed. */ |
|
792 #define PNG_sRGB_INTENT_PERCEPTUAL 0 |
|
793 #define PNG_sRGB_INTENT_RELATIVE 1 |
|
794 #define PNG_sRGB_INTENT_SATURATION 2 |
|
795 #define PNG_sRGB_INTENT_ABSOLUTE 3 |
|
796 #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ |
|
797 |
|
798 /* This is for text chunks */ |
|
799 #define PNG_KEYWORD_MAX_LENGTH 79 |
|
800 |
|
801 /* Maximum number of entries in PLTE/sPLT/tRNS arrays */ |
|
802 #define PNG_MAX_PALETTE_LENGTH 256 |
|
803 |
|
804 /* These determine if an ancillary chunk's data has been successfully read |
|
805 * from the PNG header, or if the application has filled in the corresponding |
|
806 * data in the info_struct to be written into the output file. The values |
|
807 * of the PNG_INFO_<chunk> defines should NOT be changed. |
|
808 */ |
|
809 #define PNG_INFO_gAMA 0x0001 |
|
810 #define PNG_INFO_sBIT 0x0002 |
|
811 #define PNG_INFO_cHRM 0x0004 |
|
812 #define PNG_INFO_PLTE 0x0008 |
|
813 #define PNG_INFO_tRNS 0x0010 |
|
814 #define PNG_INFO_bKGD 0x0020 |
|
815 #define PNG_INFO_hIST 0x0040 |
|
816 #define PNG_INFO_pHYs 0x0080 |
|
817 #define PNG_INFO_oFFs 0x0100 |
|
818 #define PNG_INFO_tIME 0x0200 |
|
819 #define PNG_INFO_pCAL 0x0400 |
|
820 #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */ |
|
821 #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */ |
|
822 #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */ |
|
823 #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */ |
|
824 #define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */ |
|
825 |
|
826 /* This is used for the transformation routines, as some of them |
|
827 * change these values for the row. It also should enable using |
|
828 * the routines for other purposes. |
|
829 */ |
|
830 typedef struct png_row_info_struct |
|
831 { |
|
832 png_uint_32 width; /* width of row */ |
|
833 png_size_t rowbytes; /* number of bytes in row */ |
|
834 png_byte color_type; /* color type of row */ |
|
835 png_byte bit_depth; /* bit depth of row */ |
|
836 png_byte channels; /* number of channels (1, 2, 3, or 4) */ |
|
837 png_byte pixel_depth; /* bits per pixel (depth * channels) */ |
|
838 } png_row_info; |
|
839 |
|
840 typedef png_row_info FAR * png_row_infop; |
|
841 typedef png_row_info FAR * FAR * png_row_infopp; |
|
842 |
|
843 /* The complete definition of png_struct has, as of libpng-1.5.0, |
|
844 * been moved into a separate header file that is not accessible to |
|
845 * applications. Read libpng-manual.txt or libpng.3 for more info. |
|
846 */ |
|
847 typedef struct png_struct_def png_struct; |
|
848 typedef PNG_CONST png_struct FAR * png_const_structp; |
|
849 typedef png_struct FAR * png_structp; |
|
850 |
|
851 /* These are the function types for the I/O functions and for the functions |
|
852 * that allow the user to override the default I/O functions with his or her |
|
853 * own. The png_error_ptr type should match that of user-supplied warning |
|
854 * and error functions, while the png_rw_ptr type should match that of the |
|
855 * user read/write data functions. Note that the 'write' function must not |
|
856 * modify the buffer it is passed. The 'read' function, on the other hand, is |
|
857 * expected to return the read data in the buffer. |
|
858 */ |
|
859 typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); |
|
860 typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t)); |
|
861 typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); |
|
862 typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, |
|
863 int)); |
|
864 typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, |
|
865 int)); |
|
866 |
|
867 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
868 typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); |
|
869 typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); |
|
870 |
|
871 /* The following callback receives png_uint_32 row_number, int pass for the |
|
872 * png_bytep data of the row. When transforming an interlaced image the |
|
873 * row number is the row number within the sub-image of the interlace pass, so |
|
874 * the value will increase to the height of the sub-image (not the full image) |
|
875 * then reset to 0 for the next pass. |
|
876 * |
|
877 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
|
878 * find the output pixel (x,y) given an interlaced sub-image pixel |
|
879 * (row,col,pass). (See below for these macros.) |
|
880 */ |
|
881 typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, |
|
882 png_uint_32, int)); |
|
883 #endif |
|
884 |
|
885 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ |
|
886 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) |
|
887 typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, |
|
888 png_bytep)); |
|
889 #endif |
|
890 |
|
891 #ifdef PNG_USER_CHUNKS_SUPPORTED |
|
892 typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, |
|
893 png_unknown_chunkp)); |
|
894 #endif |
|
895 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED |
|
896 typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); |
|
897 #endif |
|
898 |
|
899 #ifdef PNG_SETJMP_SUPPORTED |
|
900 /* This must match the function definition in <setjmp.h>, and the application |
|
901 * must include this before png.h to obtain the definition of jmp_buf. The |
|
902 * function is required to be PNG_NORETURN, but this is not checked. If the |
|
903 * function does return the application will crash via an abort() or similar |
|
904 * system level call. |
|
905 * |
|
906 * If you get a warning here while building the library you may need to make |
|
907 * changes to ensure that pnglibconf.h records the calling convention used by |
|
908 * your compiler. This may be very difficult - try using a different compiler |
|
909 * to build the library! |
|
910 */ |
|
911 PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); |
|
912 #endif |
|
913 |
|
914 /* Transform masks for the high-level interface */ |
|
915 #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ |
|
916 #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ |
|
917 #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ |
|
918 #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ |
|
919 #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ |
|
920 #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ |
|
921 #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ |
|
922 #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ |
|
923 #define PNG_TRANSFORM_BGR 0x0080 /* read and write */ |
|
924 #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ |
|
925 #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ |
|
926 #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ |
|
927 #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ |
|
928 /* Added to libpng-1.2.34 */ |
|
929 #define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER |
|
930 #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ |
|
931 /* Added to libpng-1.4.0 */ |
|
932 #define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ |
|
933 /* Added to libpng-1.5.4 */ |
|
934 #define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ |
|
935 #define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ |
|
936 |
|
937 /* Flags for MNG supported features */ |
|
938 #define PNG_FLAG_MNG_EMPTY_PLTE 0x01 |
|
939 #define PNG_FLAG_MNG_FILTER_64 0x04 |
|
940 #define PNG_ALL_MNG_FEATURES 0x05 |
|
941 |
|
942 /* NOTE: prior to 1.5 these functions had no 'API' style declaration, |
|
943 * this allowed the zlib default functions to be used on Windows |
|
944 * platforms. In 1.5 the zlib default malloc (which just calls malloc and |
|
945 * ignores the first argument) should be completely compatible with the |
|
946 * following. |
|
947 */ |
|
948 typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, |
|
949 png_alloc_size_t)); |
|
950 typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); |
|
951 |
|
952 typedef png_struct FAR * FAR * png_structpp; |
|
953 |
|
954 /* Section 3: exported functions |
|
955 * Here are the function definitions most commonly used. This is not |
|
956 * the place to find out how to use libpng. See libpng-manual.txt for the |
|
957 * full explanation, see example.c for the summary. This just provides |
|
958 * a simple one line description of the use of each function. |
|
959 * |
|
960 * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in |
|
961 * pngconf.h and in the *.dfn files in the scripts directory. |
|
962 * |
|
963 * PNG_EXPORT(ordinal, type, name, (args)); |
|
964 * |
|
965 * ordinal: ordinal that is used while building |
|
966 * *.def files. The ordinal value is only |
|
967 * relevant when preprocessing png.h with |
|
968 * the *.dfn files for building symbol table |
|
969 * entries, and are removed by pngconf.h. |
|
970 * type: return type of the function |
|
971 * name: function name |
|
972 * args: function arguments, with types |
|
973 * |
|
974 * When we wish to append attributes to a function prototype we use |
|
975 * the PNG_EXPORTA() macro instead. |
|
976 * |
|
977 * PNG_EXPORTA(ordinal, type, name, (args), attributes); |
|
978 * |
|
979 * ordinal, type, name, and args: same as in PNG_EXPORT(). |
|
980 * attributes: function attributes |
|
981 */ |
|
982 |
|
983 /* Returns the version number of the library */ |
|
984 PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); |
|
985 |
|
986 /* Tell lib we have already handled the first <num_bytes> magic bytes. |
|
987 * Handling more than 8 bytes from the beginning of the file is an error. |
|
988 */ |
|
989 PNG_EXPORT(2, void, png_set_sig_bytes, (png_structp png_ptr, int num_bytes)); |
|
990 |
|
991 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a |
|
992 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG |
|
993 * signature, and non-zero otherwise. Having num_to_check == 0 or |
|
994 * start > 7 will always fail (ie return non-zero). |
|
995 */ |
|
996 PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start, |
|
997 png_size_t num_to_check)); |
|
998 |
|
999 /* Simple signature checking function. This is the same as calling |
|
1000 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). |
|
1001 */ |
|
1002 #define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) |
|
1003 |
|
1004 /* Allocate and initialize png_ptr struct for reading, and any other memory. */ |
|
1005 PNG_EXPORTA(4, png_structp, png_create_read_struct, |
|
1006 (png_const_charp user_png_ver, png_voidp error_ptr, |
|
1007 png_error_ptr error_fn, png_error_ptr warn_fn), |
|
1008 PNG_ALLOCATED); |
|
1009 |
|
1010 /* Allocate and initialize png_ptr struct for writing, and any other memory */ |
|
1011 PNG_EXPORTA(5, png_structp, png_create_write_struct, |
|
1012 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
|
1013 png_error_ptr warn_fn), |
|
1014 PNG_ALLOCATED); |
|
1015 |
|
1016 PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size, |
|
1017 (png_const_structp png_ptr)); |
|
1018 |
|
1019 PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structp png_ptr, |
|
1020 png_size_t size)); |
|
1021 |
|
1022 /* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp |
|
1023 * match up. |
|
1024 */ |
|
1025 #ifdef PNG_SETJMP_SUPPORTED |
|
1026 /* This function returns the jmp_buf built in to *png_ptr. It must be |
|
1027 * supplied with an appropriate 'longjmp' function to use on that jmp_buf |
|
1028 * unless the default error function is overridden in which case NULL is |
|
1029 * acceptable. The size of the jmp_buf is checked against the actual size |
|
1030 * allocated by the library - the call will return NULL on a mismatch |
|
1031 * indicating an ABI mismatch. |
|
1032 */ |
|
1033 PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structp png_ptr, |
|
1034 png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); |
|
1035 # define png_jmpbuf(png_ptr) \ |
|
1036 (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf))) |
|
1037 #else |
|
1038 # define png_jmpbuf(png_ptr) \ |
|
1039 (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) |
|
1040 #endif |
|
1041 /* This function should be used by libpng applications in place of |
|
1042 * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it |
|
1043 * will use it; otherwise it will call PNG_ABORT(). This function was |
|
1044 * added in libpng-1.5.0. |
|
1045 */ |
|
1046 PNG_EXPORTA(9, void, png_longjmp, (png_structp png_ptr, int val), |
|
1047 PNG_NORETURN); |
|
1048 |
|
1049 #ifdef PNG_READ_SUPPORTED |
|
1050 /* Reset the compression stream */ |
|
1051 PNG_EXPORT(10, int, png_reset_zstream, (png_structp png_ptr)); |
|
1052 #endif |
|
1053 |
|
1054 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ |
|
1055 #ifdef PNG_USER_MEM_SUPPORTED |
|
1056 PNG_EXPORTA(11, png_structp, png_create_read_struct_2, |
|
1057 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
|
1058 png_error_ptr warn_fn, |
|
1059 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
|
1060 PNG_ALLOCATED); |
|
1061 PNG_EXPORTA(12, png_structp, png_create_write_struct_2, |
|
1062 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
|
1063 png_error_ptr warn_fn, |
|
1064 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
|
1065 PNG_ALLOCATED); |
|
1066 #endif |
|
1067 |
|
1068 /* Write the PNG file signature. */ |
|
1069 PNG_EXPORT(13, void, png_write_sig, (png_structp png_ptr)); |
|
1070 |
|
1071 /* Write a PNG chunk - size, type, (optional) data, CRC. */ |
|
1072 PNG_EXPORT(14, void, png_write_chunk, (png_structp png_ptr, png_const_bytep |
|
1073 chunk_name, png_const_bytep data, png_size_t length)); |
|
1074 |
|
1075 /* Write the start of a PNG chunk - length and chunk name. */ |
|
1076 PNG_EXPORT(15, void, png_write_chunk_start, (png_structp png_ptr, |
|
1077 png_const_bytep chunk_name, png_uint_32 length)); |
|
1078 |
|
1079 /* Write the data of a PNG chunk started with png_write_chunk_start(). */ |
|
1080 PNG_EXPORT(16, void, png_write_chunk_data, (png_structp png_ptr, |
|
1081 png_const_bytep data, png_size_t length)); |
|
1082 |
|
1083 /* Finish a chunk started with png_write_chunk_start() (includes CRC). */ |
|
1084 PNG_EXPORT(17, void, png_write_chunk_end, (png_structp png_ptr)); |
|
1085 |
|
1086 /* Allocate and initialize the info structure */ |
|
1087 PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_structp png_ptr), |
|
1088 PNG_ALLOCATED); |
|
1089 |
|
1090 PNG_EXPORT(19, void, png_info_init_3, (png_infopp info_ptr, |
|
1091 png_size_t png_info_struct_size)); |
|
1092 |
|
1093 /* Writes all the PNG information before the image. */ |
|
1094 PNG_EXPORT(20, void, png_write_info_before_PLTE, |
|
1095 (png_structp png_ptr, png_infop info_ptr)); |
|
1096 PNG_EXPORT(21, void, png_write_info, |
|
1097 (png_structp png_ptr, png_infop info_ptr)); |
|
1098 |
|
1099 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1100 /* Read the information before the actual image data. */ |
|
1101 PNG_EXPORT(22, void, png_read_info, |
|
1102 (png_structp png_ptr, png_infop info_ptr)); |
|
1103 #endif |
|
1104 |
|
1105 #ifdef PNG_TIME_RFC1123_SUPPORTED |
|
1106 PNG_EXPORT(23, png_const_charp, png_convert_to_rfc1123, |
|
1107 (png_structp png_ptr, |
|
1108 png_const_timep ptime)); |
|
1109 #endif |
|
1110 |
|
1111 #ifdef PNG_CONVERT_tIME_SUPPORTED |
|
1112 /* Convert from a struct tm to png_time */ |
|
1113 PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, |
|
1114 PNG_CONST struct tm FAR * ttime)); |
|
1115 |
|
1116 /* Convert from time_t to png_time. Uses gmtime() */ |
|
1117 PNG_EXPORT(25, void, png_convert_from_time_t, |
|
1118 (png_timep ptime, time_t ttime)); |
|
1119 #endif /* PNG_CONVERT_tIME_SUPPORTED */ |
|
1120 |
|
1121 #ifdef PNG_READ_EXPAND_SUPPORTED |
|
1122 /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ |
|
1123 PNG_EXPORT(26, void, png_set_expand, (png_structp png_ptr)); |
|
1124 PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structp png_ptr)); |
|
1125 PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structp png_ptr)); |
|
1126 PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr)); |
|
1127 #endif |
|
1128 |
|
1129 #ifdef PNG_READ_EXPAND_16_SUPPORTED |
|
1130 /* Expand to 16-bit channels, forces conversion of palette to RGB and expansion |
|
1131 * of a tRNS chunk if present. |
|
1132 */ |
|
1133 PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr)); |
|
1134 #endif |
|
1135 |
|
1136 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
|
1137 /* Use blue, green, red order for pixels. */ |
|
1138 PNG_EXPORT(30, void, png_set_bgr, (png_structp png_ptr)); |
|
1139 #endif |
|
1140 |
|
1141 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED |
|
1142 /* Expand the grayscale to 24-bit RGB if necessary. */ |
|
1143 PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr)); |
|
1144 #endif |
|
1145 |
|
1146 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED |
|
1147 /* Reduce RGB to grayscale. */ |
|
1148 PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr, |
|
1149 int error_action, double red, double green)); |
|
1150 PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr, |
|
1151 int error_action, png_fixed_point red, png_fixed_point green)); |
|
1152 |
|
1153 PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp |
|
1154 png_ptr)); |
|
1155 #endif |
|
1156 |
|
1157 #ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED |
|
1158 PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, |
|
1159 png_colorp palette)); |
|
1160 #endif |
|
1161 |
|
1162 #ifdef PNG_READ_ALPHA_MODE_SUPPORTED |
|
1163 /* How the alpha channel is interpreted - this affects how the color channels of |
|
1164 * a PNG file are returned when an alpha channel, or tRNS chunk in a palette |
|
1165 * file, is present. |
|
1166 * |
|
1167 * This has no effect on the way pixels are written into a PNG output |
|
1168 * datastream. The color samples in a PNG datastream are never premultiplied |
|
1169 * with the alpha samples. |
|
1170 * |
|
1171 * The default is to return data according to the PNG specification: the alpha |
|
1172 * channel is a linear measure of the contribution of the pixel to the |
|
1173 * corresponding composited pixel. The gamma encoded color channels must be |
|
1174 * scaled according to the contribution and to do this it is necessary to undo |
|
1175 * the encoding, scale the color values, perform the composition and reencode |
|
1176 * the values. This is the 'PNG' mode. |
|
1177 * |
|
1178 * The alternative is to 'associate' the alpha with the color information by |
|
1179 * storing color channel values that have been scaled by the alpha. The |
|
1180 * advantage is that the color channels can be resampled (the image can be |
|
1181 * scaled) in this form. The disadvantage is that normal practice is to store |
|
1182 * linear, not (gamma) encoded, values and this requires 16-bit channels for |
|
1183 * still images rather than the 8-bit channels that are just about sufficient if |
|
1184 * gamma encoding is used. In addition all non-transparent pixel values, |
|
1185 * including completely opaque ones, must be gamma encoded to produce the final |
|
1186 * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the |
|
1187 * latter being the two common names for associated alpha color channels.) |
|
1188 * |
|
1189 * Since it is not necessary to perform arithmetic on opaque color values so |
|
1190 * long as they are not to be resampled and are in the final color space it is |
|
1191 * possible to optimize the handling of alpha by storing the opaque pixels in |
|
1192 * the PNG format (adjusted for the output color space) while storing partially |
|
1193 * opaque pixels in the standard, linear, format. The accuracy required for |
|
1194 * standard alpha composition is relatively low, because the pixels are |
|
1195 * isolated, therefore typically the accuracy loss in storing 8-bit linear |
|
1196 * values is acceptable. (This is not true if the alpha channel is used to |
|
1197 * simulate transparency over large areas - use 16 bits or the PNG mode in |
|
1198 * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is |
|
1199 * treated as opaque only if the alpha value is equal to the maximum value. |
|
1200 * |
|
1201 * The final choice is to gamma encode the alpha channel as well. This is |
|
1202 * broken because, in practice, no implementation that uses this choice |
|
1203 * correctly undoes the encoding before handling alpha composition. Use this |
|
1204 * choice only if other serious errors in the software or hardware you use |
|
1205 * mandate it; the typical serious error is for dark halos to appear around |
|
1206 * opaque areas of the composited PNG image because of arithmetic overflow. |
|
1207 * |
|
1208 * The API function png_set_alpha_mode specifies which of these choices to use |
|
1209 * with an enumerated 'mode' value and the gamma of the required output: |
|
1210 */ |
|
1211 #define PNG_ALPHA_PNG 0 /* according to the PNG standard */ |
|
1212 #define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ |
|
1213 #define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ |
|
1214 #define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ |
|
1215 #define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ |
|
1216 #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ |
|
1217 |
|
1218 PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode, |
|
1219 double output_gamma)); |
|
1220 PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr, |
|
1221 int mode, png_fixed_point output_gamma)); |
|
1222 #endif |
|
1223 |
|
1224 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) |
|
1225 /* The output_gamma value is a screen gamma in libpng terminology: it expresses |
|
1226 * how to decode the output values, not how they are encoded. The values used |
|
1227 * correspond to the normal numbers used to describe the overall gamma of a |
|
1228 * computer display system; for example 2.2 for an sRGB conformant system. The |
|
1229 * values are scaled by 100000 in the _fixed version of the API (so 220000 for |
|
1230 * sRGB.) |
|
1231 * |
|
1232 * The inverse of the value is always used to provide a default for the PNG file |
|
1233 * encoding if it has no gAMA chunk and if png_set_gamma() has not been called |
|
1234 * to override the PNG gamma information. |
|
1235 * |
|
1236 * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode |
|
1237 * opaque pixels however pixels with lower alpha values are not encoded, |
|
1238 * regardless of the output gamma setting. |
|
1239 * |
|
1240 * When the standard Porter Duff handling is requested with mode 1 the output |
|
1241 * encoding is set to be linear and the output_gamma value is only relevant |
|
1242 * as a default for input data that has no gamma information. The linear output |
|
1243 * encoding will be overridden if png_set_gamma() is called - the results may be |
|
1244 * highly unexpected! |
|
1245 * |
|
1246 * The following numbers are derived from the sRGB standard and the research |
|
1247 * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of |
|
1248 * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing |
|
1249 * correction required to take account of any differences in the color |
|
1250 * environment of the original scene and the intended display environment; the |
|
1251 * value expresses how to *decode* the image for display, not how the original |
|
1252 * data was *encoded*. |
|
1253 * |
|
1254 * sRGB provides a peg for the PNG standard by defining a viewing environment. |
|
1255 * sRGB itself, and earlier TV standards, actually use a more complex transform |
|
1256 * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is |
|
1257 * limited to simple power laws.) By saying that an image for direct display on |
|
1258 * an sRGB conformant system should be stored with a gAMA chunk value of 45455 |
|
1259 * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification |
|
1260 * makes it possible to derive values for other display systems and |
|
1261 * environments. |
|
1262 * |
|
1263 * The Mac value is deduced from the sRGB based on an assumption that the actual |
|
1264 * extra viewing correction used in early Mac display systems was implemented as |
|
1265 * a power 1.45 lookup table. |
|
1266 * |
|
1267 * Any system where a programmable lookup table is used or where the behavior of |
|
1268 * the final display device characteristics can be changed requires system |
|
1269 * specific code to obtain the current characteristic. However this can be |
|
1270 * difficult and most PNG gamma correction only requires an approximate value. |
|
1271 * |
|
1272 * By default, if png_set_alpha_mode() is not called, libpng assumes that all |
|
1273 * values are unencoded, linear, values and that the output device also has a |
|
1274 * linear characteristic. This is only very rarely correct - it is invariably |
|
1275 * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the |
|
1276 * default if you don't know what the right answer is! |
|
1277 * |
|
1278 * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS |
|
1279 * 10.6) which used a correction table to implement a somewhat lower gamma on an |
|
1280 * otherwise sRGB system. |
|
1281 * |
|
1282 * Both these values are reserved (not simple gamma values) in order to allow |
|
1283 * more precise correction internally in the future. |
|
1284 * |
|
1285 * NOTE: the following values can be passed to either the fixed or floating |
|
1286 * point APIs, but the floating point API will also accept floating point |
|
1287 * values. |
|
1288 */ |
|
1289 #define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ |
|
1290 #define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ |
|
1291 #define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ |
|
1292 #define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ |
|
1293 #endif |
|
1294 |
|
1295 /* The following are examples of calls to png_set_alpha_mode to achieve the |
|
1296 * required overall gamma correction and, where necessary, alpha |
|
1297 * premultiplication. |
|
1298 * |
|
1299 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
|
1300 * This is the default libpng handling of the alpha channel - it is not |
|
1301 * pre-multiplied into the color components. In addition the call states |
|
1302 * that the output is for a sRGB system and causes all PNG files without gAMA |
|
1303 * chunks to be assumed to be encoded using sRGB. |
|
1304 * |
|
1305 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
|
1306 * In this case the output is assumed to be something like an sRGB conformant |
|
1307 * display preceeded by a power-law lookup table of power 1.45. This is how |
|
1308 * early Mac systems behaved. |
|
1309 * |
|
1310 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); |
|
1311 * This is the classic Jim Blinn approach and will work in academic |
|
1312 * environments where everything is done by the book. It has the shortcoming |
|
1313 * of assuming that input PNG data with no gamma information is linear - this |
|
1314 * is unlikely to be correct unless the PNG files where generated locally. |
|
1315 * Most of the time the output precision will be so low as to show |
|
1316 * significant banding in dark areas of the image. |
|
1317 * |
|
1318 * png_set_expand_16(pp); |
|
1319 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); |
|
1320 * This is a somewhat more realistic Jim Blinn inspired approach. PNG files |
|
1321 * are assumed to have the sRGB encoding if not marked with a gamma value and |
|
1322 * the output is always 16 bits per component. This permits accurate scaling |
|
1323 * and processing of the data. If you know that your input PNG files were |
|
1324 * generated locally you might need to replace PNG_DEFAULT_sRGB with the |
|
1325 * correct value for your system. |
|
1326 * |
|
1327 * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); |
|
1328 * If you just need to composite the PNG image onto an existing background |
|
1329 * and if you control the code that does this you can use the optimization |
|
1330 * setting. In this case you just copy completely opaque pixels to the |
|
1331 * output. For pixels that are not completely transparent (you just skip |
|
1332 * those) you do the composition math using png_composite or png_composite_16 |
|
1333 * below then encode the resultant 8-bit or 16-bit values to match the output |
|
1334 * encoding. |
|
1335 * |
|
1336 * Other cases |
|
1337 * If neither the PNG nor the standard linear encoding work for you because |
|
1338 * of the software or hardware you use then you have a big problem. The PNG |
|
1339 * case will probably result in halos around the image. The linear encoding |
|
1340 * will probably result in a washed out, too bright, image (it's actually too |
|
1341 * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably |
|
1342 * substantially reduce the halos. Alternatively try: |
|
1343 * |
|
1344 * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); |
|
1345 * This option will also reduce the halos, but there will be slight dark |
|
1346 * halos round the opaque parts of the image where the background is light. |
|
1347 * In the OPTIMIZED mode the halos will be light halos where the background |
|
1348 * is dark. Take your pick - the halos are unavoidable unless you can get |
|
1349 * your hardware/software fixed! (The OPTIMIZED approach is slightly |
|
1350 * faster.) |
|
1351 * |
|
1352 * When the default gamma of PNG files doesn't match the output gamma. |
|
1353 * If you have PNG files with no gamma information png_set_alpha_mode allows |
|
1354 * you to provide a default gamma, but it also sets the output gamma to the |
|
1355 * matching value. If you know your PNG files have a gamma that doesn't |
|
1356 * match the output you can take advantage of the fact that |
|
1357 * png_set_alpha_mode always sets the output gamma but only sets the PNG |
|
1358 * default if it is not already set: |
|
1359 * |
|
1360 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
|
1361 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
|
1362 * The first call sets both the default and the output gamma values, the |
|
1363 * second call overrides the output gamma without changing the default. This |
|
1364 * is easier than achieving the same effect with png_set_gamma. You must use |
|
1365 * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will |
|
1366 * fire if more than one call to png_set_alpha_mode and png_set_background is |
|
1367 * made in the same read operation, however multiple calls with PNG_ALPHA_PNG |
|
1368 * are ignored. |
|
1369 */ |
|
1370 |
|
1371 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED |
|
1372 PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr)); |
|
1373 #endif |
|
1374 |
|
1375 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ |
|
1376 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
|
1377 PNG_EXPORT(37, void, png_set_swap_alpha, (png_structp png_ptr)); |
|
1378 #endif |
|
1379 |
|
1380 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ |
|
1381 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
|
1382 PNG_EXPORT(38, void, png_set_invert_alpha, (png_structp png_ptr)); |
|
1383 #endif |
|
1384 |
|
1385 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) |
|
1386 /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */ |
|
1387 PNG_EXPORT(39, void, png_set_filler, (png_structp png_ptr, png_uint_32 filler, |
|
1388 int flags)); |
|
1389 /* The values of the PNG_FILLER_ defines should NOT be changed */ |
|
1390 # define PNG_FILLER_BEFORE 0 |
|
1391 # define PNG_FILLER_AFTER 1 |
|
1392 /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ |
|
1393 PNG_EXPORT(40, void, png_set_add_alpha, |
|
1394 (png_structp png_ptr, png_uint_32 filler, |
|
1395 int flags)); |
|
1396 #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */ |
|
1397 |
|
1398 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
|
1399 /* Swap bytes in 16-bit depth files. */ |
|
1400 PNG_EXPORT(41, void, png_set_swap, (png_structp png_ptr)); |
|
1401 #endif |
|
1402 |
|
1403 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) |
|
1404 /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ |
|
1405 PNG_EXPORT(42, void, png_set_packing, (png_structp png_ptr)); |
|
1406 #endif |
|
1407 |
|
1408 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ |
|
1409 defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
|
1410 /* Swap packing order of pixels in bytes. */ |
|
1411 PNG_EXPORT(43, void, png_set_packswap, (png_structp png_ptr)); |
|
1412 #endif |
|
1413 |
|
1414 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) |
|
1415 /* Converts files to legal bit depths. */ |
|
1416 PNG_EXPORT(44, void, png_set_shift, (png_structp png_ptr, png_const_color_8p |
|
1417 true_bits)); |
|
1418 #endif |
|
1419 |
|
1420 #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ |
|
1421 defined(PNG_WRITE_INTERLACING_SUPPORTED) |
|
1422 /* Have the code handle the interlacing. Returns the number of passes. |
|
1423 * MUST be called before png_read_update_info or png_start_read_image, |
|
1424 * otherwise it will not have the desired effect. Note that it is still |
|
1425 * necessary to call png_read_row or png_read_rows png_get_image_height |
|
1426 * times for each pass. |
|
1427 */ |
|
1428 PNG_EXPORT(45, int, png_set_interlace_handling, (png_structp png_ptr)); |
|
1429 #endif |
|
1430 |
|
1431 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) |
|
1432 /* Invert monochrome files */ |
|
1433 PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr)); |
|
1434 #endif |
|
1435 |
|
1436 #ifdef PNG_READ_BACKGROUND_SUPPORTED |
|
1437 /* Handle alpha and tRNS by replacing with a background color. Prior to |
|
1438 * libpng-1.5.4 this API must not be called before the PNG file header has been |
|
1439 * read. Doing so will result in unexpected behavior and possible warnings or |
|
1440 * errors if the PNG file contains a bKGD chunk. |
|
1441 */ |
|
1442 PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr, |
|
1443 png_const_color_16p background_color, int background_gamma_code, |
|
1444 int need_expand, double background_gamma)); |
|
1445 PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr, |
|
1446 png_const_color_16p background_color, int background_gamma_code, |
|
1447 int need_expand, png_fixed_point background_gamma)); |
|
1448 #endif |
|
1449 #ifdef PNG_READ_BACKGROUND_SUPPORTED |
|
1450 # define PNG_BACKGROUND_GAMMA_UNKNOWN 0 |
|
1451 # define PNG_BACKGROUND_GAMMA_SCREEN 1 |
|
1452 # define PNG_BACKGROUND_GAMMA_FILE 2 |
|
1453 # define PNG_BACKGROUND_GAMMA_UNIQUE 3 |
|
1454 #endif |
|
1455 |
|
1456 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED |
|
1457 /* Scale a 16-bit depth file down to 8-bit, accurately. */ |
|
1458 PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr)); |
|
1459 #endif |
|
1460 |
|
1461 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED |
|
1462 #define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */ |
|
1463 /* Strip the second byte of information from a 16-bit depth file. */ |
|
1464 PNG_EXPORT(48, void, png_set_strip_16, (png_structp png_ptr)); |
|
1465 #endif |
|
1466 |
|
1467 #ifdef PNG_READ_QUANTIZE_SUPPORTED |
|
1468 /* Turn on quantizing, and reduce the palette to the number of colors |
|
1469 * available. |
|
1470 */ |
|
1471 PNG_EXPORT(49, void, png_set_quantize, |
|
1472 (png_structp png_ptr, png_colorp palette, |
|
1473 int num_palette, int maximum_colors, png_const_uint_16p histogram, |
|
1474 int full_quantize)); |
|
1475 #endif |
|
1476 |
|
1477 #ifdef PNG_READ_GAMMA_SUPPORTED |
|
1478 /* The threshold on gamma processing is configurable but hard-wired into the |
|
1479 * library. The following is the floating point variant. |
|
1480 */ |
|
1481 #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) |
|
1482 |
|
1483 /* Handle gamma correction. Screen_gamma=(display_exponent). |
|
1484 * NOTE: this API simply sets the screen and file gamma values. It will |
|
1485 * therefore override the value for gamma in a PNG file if it is called after |
|
1486 * the file header has been read - use with care - call before reading the PNG |
|
1487 * file for best results! |
|
1488 * |
|
1489 * These routines accept the same gamma values as png_set_alpha_mode (described |
|
1490 * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either |
|
1491 * API (floating point or fixed.) Notice, however, that the 'file_gamma' value |
|
1492 * is the inverse of a 'screen gamma' value. |
|
1493 */ |
|
1494 PNG_FP_EXPORT(50, void, png_set_gamma, |
|
1495 (png_structp png_ptr, double screen_gamma, |
|
1496 double override_file_gamma)); |
|
1497 PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr, |
|
1498 png_fixed_point screen_gamma, png_fixed_point override_file_gamma)); |
|
1499 #endif |
|
1500 |
|
1501 #ifdef PNG_WRITE_FLUSH_SUPPORTED |
|
1502 /* Set how many lines between output flushes - 0 for no flushing */ |
|
1503 PNG_EXPORT(51, void, png_set_flush, (png_structp png_ptr, int nrows)); |
|
1504 /* Flush the current PNG output buffer */ |
|
1505 PNG_EXPORT(52, void, png_write_flush, (png_structp png_ptr)); |
|
1506 #endif |
|
1507 |
|
1508 /* Optional update palette with requested transformations */ |
|
1509 PNG_EXPORT(53, void, png_start_read_image, (png_structp png_ptr)); |
|
1510 |
|
1511 /* Optional call to update the users info structure */ |
|
1512 PNG_EXPORT(54, void, png_read_update_info, |
|
1513 (png_structp png_ptr, png_infop info_ptr)); |
|
1514 |
|
1515 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1516 /* Read one or more rows of image data. */ |
|
1517 PNG_EXPORT(55, void, png_read_rows, (png_structp png_ptr, png_bytepp row, |
|
1518 png_bytepp display_row, png_uint_32 num_rows)); |
|
1519 #endif |
|
1520 |
|
1521 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1522 /* Read a row of data. */ |
|
1523 PNG_EXPORT(56, void, png_read_row, (png_structp png_ptr, png_bytep row, |
|
1524 png_bytep display_row)); |
|
1525 #endif |
|
1526 |
|
1527 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1528 /* Read the whole image into memory at once. */ |
|
1529 PNG_EXPORT(57, void, png_read_image, (png_structp png_ptr, png_bytepp image)); |
|
1530 #endif |
|
1531 |
|
1532 /* Write a row of image data */ |
|
1533 PNG_EXPORT(58, void, png_write_row, |
|
1534 (png_structp png_ptr, png_const_bytep row)); |
|
1535 |
|
1536 /* Write a few rows of image data: (*row) is not written; however, the type |
|
1537 * is declared as writeable to maintain compatibility with previous versions |
|
1538 * of libpng and to allow the 'display_row' array from read_rows to be passed |
|
1539 * unchanged to write_rows. |
|
1540 */ |
|
1541 PNG_EXPORT(59, void, png_write_rows, (png_structp png_ptr, png_bytepp row, |
|
1542 png_uint_32 num_rows)); |
|
1543 |
|
1544 /* Write the image data */ |
|
1545 PNG_EXPORT(60, void, png_write_image, |
|
1546 (png_structp png_ptr, png_bytepp image)); |
|
1547 |
|
1548 /* Write the end of the PNG file. */ |
|
1549 PNG_EXPORT(61, void, png_write_end, |
|
1550 (png_structp png_ptr, png_infop info_ptr)); |
|
1551 |
|
1552 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
|
1553 /* Read the end of the PNG file. */ |
|
1554 PNG_EXPORT(62, void, png_read_end, (png_structp png_ptr, png_infop info_ptr)); |
|
1555 #endif |
|
1556 |
|
1557 /* Free any memory associated with the png_info_struct */ |
|
1558 PNG_EXPORT(63, void, png_destroy_info_struct, (png_structp png_ptr, |
|
1559 png_infopp info_ptr_ptr)); |
|
1560 |
|
1561 /* Free any memory associated with the png_struct and the png_info_structs */ |
|
1562 PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, |
|
1563 png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); |
|
1564 |
|
1565 /* Free any memory associated with the png_struct and the png_info_structs */ |
|
1566 PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, |
|
1567 png_infopp info_ptr_ptr)); |
|
1568 |
|
1569 /* Set the libpng method of handling chunk CRC errors */ |
|
1570 PNG_EXPORT(66, void, png_set_crc_action, |
|
1571 (png_structp png_ptr, int crit_action, int ancil_action)); |
|
1572 |
|
1573 /* Values for png_set_crc_action() say how to handle CRC errors in |
|
1574 * ancillary and critical chunks, and whether to use the data contained |
|
1575 * therein. Note that it is impossible to "discard" data in a critical |
|
1576 * chunk. For versions prior to 0.90, the action was always error/quit, |
|
1577 * whereas in version 0.90 and later, the action for CRC errors in ancillary |
|
1578 * chunks is warn/discard. These values should NOT be changed. |
|
1579 * |
|
1580 * value action:critical action:ancillary |
|
1581 */ |
|
1582 #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ |
|
1583 #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ |
|
1584 #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ |
|
1585 #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ |
|
1586 #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ |
|
1587 #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ |
|
1588 |
|
1589 /* These functions give the user control over the scan-line filtering in |
|
1590 * libpng and the compression methods used by zlib. These functions are |
|
1591 * mainly useful for testing, as the defaults should work with most users. |
|
1592 * Those users who are tight on memory or want faster performance at the |
|
1593 * expense of compression can modify them. See the compression library |
|
1594 * header file (zlib.h) for an explination of the compression functions. |
|
1595 */ |
|
1596 |
|
1597 /* Set the filtering method(s) used by libpng. Currently, the only valid |
|
1598 * value for "method" is 0. |
|
1599 */ |
|
1600 PNG_EXPORT(67, void, png_set_filter, |
|
1601 (png_structp png_ptr, int method, int filters)); |
|
1602 |
|
1603 /* Flags for png_set_filter() to say which filters to use. The flags |
|
1604 * are chosen so that they don't conflict with real filter types |
|
1605 * below, in case they are supplied instead of the #defined constants. |
|
1606 * These values should NOT be changed. |
|
1607 */ |
|
1608 #define PNG_NO_FILTERS 0x00 |
|
1609 #define PNG_FILTER_NONE 0x08 |
|
1610 #define PNG_FILTER_SUB 0x10 |
|
1611 #define PNG_FILTER_UP 0x20 |
|
1612 #define PNG_FILTER_AVG 0x40 |
|
1613 #define PNG_FILTER_PAETH 0x80 |
|
1614 #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \ |
|
1615 PNG_FILTER_AVG | PNG_FILTER_PAETH) |
|
1616 |
|
1617 /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. |
|
1618 * These defines should NOT be changed. |
|
1619 */ |
|
1620 #define PNG_FILTER_VALUE_NONE 0 |
|
1621 #define PNG_FILTER_VALUE_SUB 1 |
|
1622 #define PNG_FILTER_VALUE_UP 2 |
|
1623 #define PNG_FILTER_VALUE_AVG 3 |
|
1624 #define PNG_FILTER_VALUE_PAETH 4 |
|
1625 #define PNG_FILTER_VALUE_LAST 5 |
|
1626 |
|
1627 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */ |
|
1628 /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_ |
|
1629 * defines, either the default (minimum-sum-of-absolute-differences), or |
|
1630 * the experimental method (weighted-minimum-sum-of-absolute-differences). |
|
1631 * |
|
1632 * Weights are factors >= 1.0, indicating how important it is to keep the |
|
1633 * filter type consistent between rows. Larger numbers mean the current |
|
1634 * filter is that many times as likely to be the same as the "num_weights" |
|
1635 * previous filters. This is cumulative for each previous row with a weight. |
|
1636 * There needs to be "num_weights" values in "filter_weights", or it can be |
|
1637 * NULL if the weights aren't being specified. Weights have no influence on |
|
1638 * the selection of the first row filter. Well chosen weights can (in theory) |
|
1639 * improve the compression for a given image. |
|
1640 * |
|
1641 * Costs are factors >= 1.0 indicating the relative decoding costs of a |
|
1642 * filter type. Higher costs indicate more decoding expense, and are |
|
1643 * therefore less likely to be selected over a filter with lower computational |
|
1644 * costs. There needs to be a value in "filter_costs" for each valid filter |
|
1645 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't |
|
1646 * setting the costs. Costs try to improve the speed of decompression without |
|
1647 * unduly increasing the compressed image size. |
|
1648 * |
|
1649 * A negative weight or cost indicates the default value is to be used, and |
|
1650 * values in the range [0.0, 1.0) indicate the value is to remain unchanged. |
|
1651 * The default values for both weights and costs are currently 1.0, but may |
|
1652 * change if good general weighting/cost heuristics can be found. If both |
|
1653 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method |
|
1654 * to the UNWEIGHTED method, but with added encoding time/computation. |
|
1655 */ |
|
1656 PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr, |
|
1657 int heuristic_method, int num_weights, png_const_doublep filter_weights, |
|
1658 png_const_doublep filter_costs)); |
|
1659 PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, |
|
1660 (png_structp png_ptr, |
|
1661 int heuristic_method, int num_weights, png_const_fixed_point_p |
|
1662 filter_weights, png_const_fixed_point_p filter_costs)); |
|
1663 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ |
|
1664 |
|
1665 /* Heuristic used for row filter selection. These defines should NOT be |
|
1666 * changed. |
|
1667 */ |
|
1668 #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ |
|
1669 #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ |
|
1670 #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ |
|
1671 #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ |
|
1672 |
|
1673 #ifdef PNG_WRITE_SUPPORTED |
|
1674 /* Set the library compression level. Currently, valid values range from |
|
1675 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 |
|
1676 * (0 - no compression, 9 - "maximal" compression). Note that tests have |
|
1677 * shown that zlib compression levels 3-6 usually perform as well as level 9 |
|
1678 * for PNG images, and do considerably fewer caclulations. In the future, |
|
1679 * these values may not correspond directly to the zlib compression levels. |
|
1680 */ |
|
1681 PNG_EXPORT(69, void, png_set_compression_level, |
|
1682 (png_structp png_ptr, int level)); |
|
1683 |
|
1684 PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr, |
|
1685 int mem_level)); |
|
1686 |
|
1687 PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr, |
|
1688 int strategy)); |
|
1689 |
|
1690 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
|
1691 * smaller value of window_bits if it can do so safely. |
|
1692 */ |
|
1693 PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr, |
|
1694 int window_bits)); |
|
1695 |
|
1696 PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr, |
|
1697 int method)); |
|
1698 #endif |
|
1699 |
|
1700 #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED |
|
1701 /* Also set zlib parameters for compressing non-IDAT chunks */ |
|
1702 PNG_EXPORT(222, void, png_set_text_compression_level, |
|
1703 (png_structp png_ptr, int level)); |
|
1704 |
|
1705 PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr, |
|
1706 int mem_level)); |
|
1707 |
|
1708 PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr, |
|
1709 int strategy)); |
|
1710 |
|
1711 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
|
1712 * smaller value of window_bits if it can do so safely. |
|
1713 */ |
|
1714 PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp |
|
1715 png_ptr, int window_bits)); |
|
1716 |
|
1717 PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr, |
|
1718 int method)); |
|
1719 #endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */ |
|
1720 |
|
1721 /* These next functions are called for input/output, memory, and error |
|
1722 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, |
|
1723 * and call standard C I/O routines such as fread(), fwrite(), and |
|
1724 * fprintf(). These functions can be made to use other I/O routines |
|
1725 * at run time for those applications that need to handle I/O in a |
|
1726 * different manner by calling png_set_???_fn(). See libpng-manual.txt for |
|
1727 * more information. |
|
1728 */ |
|
1729 |
|
1730 #ifdef PNG_STDIO_SUPPORTED |
|
1731 /* Initialize the input/output for the PNG file to the default functions. */ |
|
1732 PNG_EXPORT(74, void, png_init_io, (png_structp png_ptr, png_FILE_p fp)); |
|
1733 #endif |
|
1734 |
|
1735 /* Replace the (error and abort), and warning functions with user |
|
1736 * supplied functions. If no messages are to be printed you must still |
|
1737 * write and use replacement functions. The replacement error_fn should |
|
1738 * still do a longjmp to the last setjmp location if you are using this |
|
1739 * method of error handling. If error_fn or warning_fn is NULL, the |
|
1740 * default function will be used. |
|
1741 */ |
|
1742 |
|
1743 PNG_EXPORT(75, void, png_set_error_fn, |
|
1744 (png_structp png_ptr, png_voidp error_ptr, |
|
1745 png_error_ptr error_fn, png_error_ptr warning_fn)); |
|
1746 |
|
1747 /* Return the user pointer associated with the error functions */ |
|
1748 PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structp png_ptr)); |
|
1749 |
|
1750 /* Replace the default data output functions with a user supplied one(s). |
|
1751 * If buffered output is not used, then output_flush_fn can be set to NULL. |
|
1752 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time |
|
1753 * output_flush_fn will be ignored (and thus can be NULL). |
|
1754 * It is probably a mistake to use NULL for output_flush_fn if |
|
1755 * write_data_fn is not also NULL unless you have built libpng with |
|
1756 * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's |
|
1757 * default flush function, which uses the standard *FILE structure, will |
|
1758 * be used. |
|
1759 */ |
|
1760 PNG_EXPORT(77, void, png_set_write_fn, (png_structp png_ptr, png_voidp io_ptr, |
|
1761 png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); |
|
1762 |
|
1763 /* Replace the default data input function with a user supplied one. */ |
|
1764 PNG_EXPORT(78, void, png_set_read_fn, (png_structp png_ptr, png_voidp io_ptr, |
|
1765 png_rw_ptr read_data_fn)); |
|
1766 |
|
1767 /* Return the user pointer associated with the I/O functions */ |
|
1768 PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_structp png_ptr)); |
|
1769 |
|
1770 PNG_EXPORT(80, void, png_set_read_status_fn, (png_structp png_ptr, |
|
1771 png_read_status_ptr read_row_fn)); |
|
1772 |
|
1773 PNG_EXPORT(81, void, png_set_write_status_fn, (png_structp png_ptr, |
|
1774 png_write_status_ptr write_row_fn)); |
|
1775 |
|
1776 #ifdef PNG_USER_MEM_SUPPORTED |
|
1777 /* Replace the default memory allocation functions with user supplied one(s). */ |
|
1778 PNG_EXPORT(82, void, png_set_mem_fn, (png_structp png_ptr, png_voidp mem_ptr, |
|
1779 png_malloc_ptr malloc_fn, png_free_ptr free_fn)); |
|
1780 /* Return the user pointer associated with the memory functions */ |
|
1781 PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structp png_ptr)); |
|
1782 #endif |
|
1783 |
|
1784 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED |
|
1785 PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structp png_ptr, |
|
1786 png_user_transform_ptr read_user_transform_fn)); |
|
1787 #endif |
|
1788 |
|
1789 #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED |
|
1790 PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structp png_ptr, |
|
1791 png_user_transform_ptr write_user_transform_fn)); |
|
1792 #endif |
|
1793 |
|
1794 #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED |
|
1795 PNG_EXPORT(86, void, png_set_user_transform_info, (png_structp png_ptr, |
|
1796 png_voidp user_transform_ptr, int user_transform_depth, |
|
1797 int user_transform_channels)); |
|
1798 /* Return the user pointer associated with the user transform functions */ |
|
1799 PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, |
|
1800 (png_const_structp png_ptr)); |
|
1801 #endif |
|
1802 |
|
1803 #ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED |
|
1804 /* Return information about the row currently being processed. Note that these |
|
1805 * APIs do not fail but will return unexpected results if called outside a user |
|
1806 * transform callback. Also note that when transforming an interlaced image the |
|
1807 * row number is the row number within the sub-image of the interlace pass, so |
|
1808 * the value will increase to the height of the sub-image (not the full image) |
|
1809 * then reset to 0 for the next pass. |
|
1810 * |
|
1811 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
|
1812 * find the output pixel (x,y) given an interlaced sub-image pixel |
|
1813 * (row,col,pass). (See below for these macros.) |
|
1814 */ |
|
1815 PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp)); |
|
1816 PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp)); |
|
1817 #endif |
|
1818 |
|
1819 #ifdef PNG_USER_CHUNKS_SUPPORTED |
|
1820 PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structp png_ptr, |
|
1821 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); |
|
1822 PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structp png_ptr)); |
|
1823 #endif |
|
1824 |
|
1825 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
1826 /* Sets the function callbacks for the push reader, and a pointer to a |
|
1827 * user-defined structure available to the callback functions. |
|
1828 */ |
|
1829 PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structp png_ptr, |
|
1830 png_voidp progressive_ptr, png_progressive_info_ptr info_fn, |
|
1831 png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); |
|
1832 |
|
1833 /* Returns the user pointer associated with the push read functions */ |
|
1834 PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, (png_const_structp png_ptr)); |
|
1835 |
|
1836 /* Function to be called when data becomes available */ |
|
1837 PNG_EXPORT(92, void, png_process_data, |
|
1838 (png_structp png_ptr, png_infop info_ptr, |
|
1839 png_bytep buffer, png_size_t buffer_size)); |
|
1840 |
|
1841 /* A function which may be called *only* within png_process_data to stop the |
|
1842 * processing of any more data. The function returns the number of bytes |
|
1843 * remaining, excluding any that libpng has cached internally. A subsequent |
|
1844 * call to png_process_data must supply these bytes again. If the argument |
|
1845 * 'save' is set to true the routine will first save all the pending data and |
|
1846 * will always return 0. |
|
1847 */ |
|
1848 PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structp, int save)); |
|
1849 |
|
1850 /* A function which may be called *only* outside (after) a call to |
|
1851 * png_process_data. It returns the number of bytes of data to skip in the |
|
1852 * input. Normally it will return 0, but if it returns a non-zero value the |
|
1853 * application must skip than number of bytes of input data and pass the |
|
1854 * following data to the next call to png_process_data. |
|
1855 */ |
|
1856 PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structp)); |
|
1857 |
|
1858 /* Function that combines rows. 'new_row' is a flag that should come from |
|
1859 * the callback and be non-NULL if anything needs to be done; the library |
|
1860 * stores its own version of the new data internally and ignores the passed |
|
1861 * in value. |
|
1862 */ |
|
1863 PNG_EXPORT(93, void, png_progressive_combine_row, (png_structp png_ptr, |
|
1864 png_bytep old_row, png_const_bytep new_row)); |
|
1865 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ |
|
1866 |
|
1867 PNG_EXPORTA(94, png_voidp, png_malloc, |
|
1868 (png_structp png_ptr, png_alloc_size_t size), |
|
1869 PNG_ALLOCATED); |
|
1870 /* Added at libpng version 1.4.0 */ |
|
1871 PNG_EXPORTA(95, png_voidp, png_calloc, |
|
1872 (png_structp png_ptr, png_alloc_size_t size), |
|
1873 PNG_ALLOCATED); |
|
1874 |
|
1875 /* Added at libpng version 1.2.4 */ |
|
1876 PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_structp png_ptr, |
|
1877 png_alloc_size_t size), PNG_ALLOCATED); |
|
1878 |
|
1879 /* Frees a pointer allocated by png_malloc() */ |
|
1880 PNG_EXPORT(97, void, png_free, (png_structp png_ptr, png_voidp ptr)); |
|
1881 |
|
1882 /* Free data that was allocated internally */ |
|
1883 PNG_EXPORT(98, void, png_free_data, |
|
1884 (png_structp png_ptr, png_infop info_ptr, png_uint_32 free_me, int num)); |
|
1885 |
|
1886 /* Reassign responsibility for freeing existing data, whether allocated |
|
1887 * by libpng or by the application */ |
|
1888 PNG_EXPORT(99, void, png_data_freer, |
|
1889 (png_structp png_ptr, png_infop info_ptr, int freer, png_uint_32 mask)); |
|
1890 |
|
1891 /* Assignments for png_data_freer */ |
|
1892 #define PNG_DESTROY_WILL_FREE_DATA 1 |
|
1893 #define PNG_SET_WILL_FREE_DATA 1 |
|
1894 #define PNG_USER_WILL_FREE_DATA 2 |
|
1895 /* Flags for png_ptr->free_me and info_ptr->free_me */ |
|
1896 #define PNG_FREE_HIST 0x0008 |
|
1897 #define PNG_FREE_ICCP 0x0010 |
|
1898 #define PNG_FREE_SPLT 0x0020 |
|
1899 #define PNG_FREE_ROWS 0x0040 |
|
1900 #define PNG_FREE_PCAL 0x0080 |
|
1901 #define PNG_FREE_SCAL 0x0100 |
|
1902 #define PNG_FREE_UNKN 0x0200 |
|
1903 #define PNG_FREE_LIST 0x0400 |
|
1904 #define PNG_FREE_PLTE 0x1000 |
|
1905 #define PNG_FREE_TRNS 0x2000 |
|
1906 #define PNG_FREE_TEXT 0x4000 |
|
1907 #define PNG_FREE_ALL 0x7fff |
|
1908 #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ |
|
1909 |
|
1910 #ifdef PNG_USER_MEM_SUPPORTED |
|
1911 PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_structp png_ptr, |
|
1912 png_alloc_size_t size), PNG_ALLOCATED); |
|
1913 PNG_EXPORT(101, void, png_free_default, (png_structp png_ptr, png_voidp ptr)); |
|
1914 #endif |
|
1915 |
|
1916 #ifdef PNG_ERROR_TEXT_SUPPORTED |
|
1917 /* Fatal error in PNG image of libpng - can't continue */ |
|
1918 PNG_EXPORTA(102, void, png_error, |
|
1919 (png_structp png_ptr, png_const_charp error_message), |
|
1920 PNG_NORETURN); |
|
1921 |
|
1922 /* The same, but the chunk name is prepended to the error string. */ |
|
1923 PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr, |
|
1924 png_const_charp error_message), PNG_NORETURN); |
|
1925 |
|
1926 #else |
|
1927 /* Fatal error in PNG image of libpng - can't continue */ |
|
1928 PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN); |
|
1929 #endif |
|
1930 |
|
1931 #ifdef PNG_WARNINGS_SUPPORTED |
|
1932 /* Non-fatal error in libpng. Can continue, but may have a problem. */ |
|
1933 PNG_EXPORT(105, void, png_warning, (png_structp png_ptr, |
|
1934 png_const_charp warning_message)); |
|
1935 |
|
1936 /* Non-fatal error in libpng, chunk name is prepended to message. */ |
|
1937 PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr, |
|
1938 png_const_charp warning_message)); |
|
1939 #endif |
|
1940 |
|
1941 #ifdef PNG_BENIGN_ERRORS_SUPPORTED |
|
1942 /* Benign error in libpng. Can continue, but may have a problem. |
|
1943 * User can choose whether to handle as a fatal error or as a warning. */ |
|
1944 # undef png_benign_error |
|
1945 PNG_EXPORT(107, void, png_benign_error, (png_structp png_ptr, |
|
1946 png_const_charp warning_message)); |
|
1947 |
|
1948 /* Same, chunk name is prepended to message. */ |
|
1949 # undef png_chunk_benign_error |
|
1950 PNG_EXPORT(108, void, png_chunk_benign_error, (png_structp png_ptr, |
|
1951 png_const_charp warning_message)); |
|
1952 |
|
1953 PNG_EXPORT(109, void, png_set_benign_errors, |
|
1954 (png_structp png_ptr, int allowed)); |
|
1955 #else |
|
1956 # ifdef PNG_ALLOW_BENIGN_ERRORS |
|
1957 # define png_benign_error png_warning |
|
1958 # define png_chunk_benign_error png_chunk_warning |
|
1959 # else |
|
1960 # define png_benign_error png_error |
|
1961 # define png_chunk_benign_error png_chunk_error |
|
1962 # endif |
|
1963 #endif |
|
1964 |
|
1965 /* The png_set_<chunk> functions are for storing values in the png_info_struct. |
|
1966 * Similarly, the png_get_<chunk> calls are used to read values from the |
|
1967 * png_info_struct, either storing the parameters in the passed variables, or |
|
1968 * setting pointers into the png_info_struct where the data is stored. The |
|
1969 * png_get_<chunk> functions return a non-zero value if the data was available |
|
1970 * in info_ptr, or return zero and do not change any of the parameters if the |
|
1971 * data was not available. |
|
1972 * |
|
1973 * These functions should be used instead of directly accessing png_info |
|
1974 * to avoid problems with future changes in the size and internal layout of |
|
1975 * png_info_struct. |
|
1976 */ |
|
1977 /* Returns "flag" if chunk data is valid in info_ptr. */ |
|
1978 PNG_EXPORT(110, png_uint_32, png_get_valid, |
|
1979 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
1980 png_uint_32 flag)); |
|
1981 |
|
1982 /* Returns number of bytes needed to hold a transformed row. */ |
|
1983 PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structp png_ptr, |
|
1984 png_const_infop info_ptr)); |
|
1985 |
|
1986 #ifdef PNG_INFO_IMAGE_SUPPORTED |
|
1987 /* Returns row_pointers, which is an array of pointers to scanlines that was |
|
1988 * returned from png_read_png(). |
|
1989 */ |
|
1990 PNG_EXPORT(112, png_bytepp, png_get_rows, |
|
1991 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
1992 /* Set row_pointers, which is an array of pointers to scanlines for use |
|
1993 * by png_write_png(). |
|
1994 */ |
|
1995 PNG_EXPORT(113, void, png_set_rows, (png_structp png_ptr, |
|
1996 png_infop info_ptr, png_bytepp row_pointers)); |
|
1997 #endif |
|
1998 |
|
1999 /* Returns number of color channels in image. */ |
|
2000 PNG_EXPORT(114, png_byte, png_get_channels, |
|
2001 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2002 |
|
2003 #ifdef PNG_EASY_ACCESS_SUPPORTED |
|
2004 /* Returns image width in pixels. */ |
|
2005 PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structp png_ptr, |
|
2006 png_const_infop info_ptr)); |
|
2007 |
|
2008 /* Returns image height in pixels. */ |
|
2009 PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structp png_ptr, |
|
2010 png_const_infop info_ptr)); |
|
2011 |
|
2012 /* Returns image bit_depth. */ |
|
2013 PNG_EXPORT(117, png_byte, png_get_bit_depth, |
|
2014 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2015 |
|
2016 /* Returns image color_type. */ |
|
2017 PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structp png_ptr, |
|
2018 png_const_infop info_ptr)); |
|
2019 |
|
2020 /* Returns image filter_type. */ |
|
2021 PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structp png_ptr, |
|
2022 png_const_infop info_ptr)); |
|
2023 |
|
2024 /* Returns image interlace_type. */ |
|
2025 PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structp png_ptr, |
|
2026 png_const_infop info_ptr)); |
|
2027 |
|
2028 /* Returns image compression_type. */ |
|
2029 PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structp png_ptr, |
|
2030 png_const_infop info_ptr)); |
|
2031 |
|
2032 /* Returns image resolution in pixels per meter, from pHYs chunk data. */ |
|
2033 PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, |
|
2034 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2035 PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, |
|
2036 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2037 PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, |
|
2038 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2039 |
|
2040 /* Returns pixel aspect ratio, computed from pHYs chunk data. */ |
|
2041 PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, |
|
2042 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2043 PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, |
|
2044 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2045 |
|
2046 /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ |
|
2047 PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, |
|
2048 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2049 PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, |
|
2050 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2051 PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, |
|
2052 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2053 PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, |
|
2054 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2055 |
|
2056 #endif /* PNG_EASY_ACCESS_SUPPORTED */ |
|
2057 |
|
2058 /* Returns pointer to signature string read from PNG header */ |
|
2059 PNG_EXPORT(130, png_const_bytep, png_get_signature, |
|
2060 (png_const_structp png_ptr, png_infop info_ptr)); |
|
2061 |
|
2062 #ifdef PNG_bKGD_SUPPORTED |
|
2063 PNG_EXPORT(131, png_uint_32, png_get_bKGD, |
|
2064 (png_const_structp png_ptr, png_infop info_ptr, |
|
2065 png_color_16p *background)); |
|
2066 #endif |
|
2067 |
|
2068 #ifdef PNG_bKGD_SUPPORTED |
|
2069 PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr, |
|
2070 png_const_color_16p background)); |
|
2071 #endif |
|
2072 |
|
2073 #ifdef PNG_cHRM_SUPPORTED |
|
2074 PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structp png_ptr, |
|
2075 png_const_infop info_ptr, double *white_x, double *white_y, double *red_x, |
|
2076 double *red_y, double *green_x, double *green_y, double *blue_x, |
|
2077 double *blue_y)); |
|
2078 #ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */ |
|
2079 PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, |
|
2080 (png_const_structp png_ptr, |
|
2081 png_const_infop info_ptr, png_fixed_point *int_white_x, |
|
2082 png_fixed_point *int_white_y, png_fixed_point *int_red_x, |
|
2083 png_fixed_point *int_red_y, png_fixed_point *int_green_x, |
|
2084 png_fixed_point *int_green_y, png_fixed_point *int_blue_x, |
|
2085 png_fixed_point *int_blue_y)); |
|
2086 #endif |
|
2087 #endif |
|
2088 |
|
2089 #ifdef PNG_cHRM_SUPPORTED |
|
2090 PNG_FP_EXPORT(135, void, png_set_cHRM, |
|
2091 (png_structp png_ptr, png_infop info_ptr, |
|
2092 double white_x, double white_y, double red_x, double red_y, double green_x, |
|
2093 double green_y, double blue_x, double blue_y)); |
|
2094 PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_structp png_ptr, |
|
2095 png_infop info_ptr, png_fixed_point int_white_x, |
|
2096 png_fixed_point int_white_y, png_fixed_point int_red_x, |
|
2097 png_fixed_point int_red_y, png_fixed_point int_green_x, |
|
2098 png_fixed_point int_green_y, png_fixed_point int_blue_x, |
|
2099 png_fixed_point int_blue_y)); |
|
2100 #endif |
|
2101 |
|
2102 #ifdef PNG_gAMA_SUPPORTED |
|
2103 PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, |
|
2104 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2105 double *file_gamma)); |
|
2106 PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, |
|
2107 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2108 png_fixed_point *int_file_gamma)); |
|
2109 #endif |
|
2110 |
|
2111 #ifdef PNG_gAMA_SUPPORTED |
|
2112 PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr, |
|
2113 png_infop info_ptr, double file_gamma)); |
|
2114 PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr, |
|
2115 png_infop info_ptr, png_fixed_point int_file_gamma)); |
|
2116 #endif |
|
2117 |
|
2118 #ifdef PNG_hIST_SUPPORTED |
|
2119 PNG_EXPORT(141, png_uint_32, png_get_hIST, |
|
2120 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2121 png_uint_16p *hist)); |
|
2122 #endif |
|
2123 |
|
2124 #ifdef PNG_hIST_SUPPORTED |
|
2125 PNG_EXPORT(142, void, png_set_hIST, (png_structp png_ptr, |
|
2126 png_infop info_ptr, png_const_uint_16p hist)); |
|
2127 #endif |
|
2128 |
|
2129 PNG_EXPORT(143, png_uint_32, png_get_IHDR, |
|
2130 (png_structp png_ptr, png_infop info_ptr, |
|
2131 png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type, |
|
2132 int *interlace_method, int *compression_method, int *filter_method)); |
|
2133 |
|
2134 PNG_EXPORT(144, void, png_set_IHDR, |
|
2135 (png_structp png_ptr, png_infop info_ptr, |
|
2136 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, |
|
2137 int interlace_method, int compression_method, int filter_method)); |
|
2138 |
|
2139 #ifdef PNG_oFFs_SUPPORTED |
|
2140 PNG_EXPORT(145, png_uint_32, png_get_oFFs, |
|
2141 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2142 png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)); |
|
2143 #endif |
|
2144 |
|
2145 #ifdef PNG_oFFs_SUPPORTED |
|
2146 PNG_EXPORT(146, void, png_set_oFFs, |
|
2147 (png_structp png_ptr, png_infop info_ptr, |
|
2148 png_int_32 offset_x, png_int_32 offset_y, int unit_type)); |
|
2149 #endif |
|
2150 |
|
2151 #ifdef PNG_pCAL_SUPPORTED |
|
2152 PNG_EXPORT(147, png_uint_32, png_get_pCAL, |
|
2153 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2154 png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, |
|
2155 int *nparams, |
|
2156 png_charp *units, png_charpp *params)); |
|
2157 #endif |
|
2158 |
|
2159 #ifdef PNG_pCAL_SUPPORTED |
|
2160 PNG_EXPORT(148, void, png_set_pCAL, (png_structp png_ptr, |
|
2161 png_infop info_ptr, |
|
2162 png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type, |
|
2163 int nparams, png_const_charp units, png_charpp params)); |
|
2164 #endif |
|
2165 |
|
2166 #ifdef PNG_pHYs_SUPPORTED |
|
2167 PNG_EXPORT(149, png_uint_32, png_get_pHYs, |
|
2168 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2169 png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)); |
|
2170 #endif |
|
2171 |
|
2172 #ifdef PNG_pHYs_SUPPORTED |
|
2173 PNG_EXPORT(150, void, png_set_pHYs, |
|
2174 (png_structp png_ptr, png_infop info_ptr, |
|
2175 png_uint_32 res_x, png_uint_32 res_y, int unit_type)); |
|
2176 #endif |
|
2177 |
|
2178 PNG_EXPORT(151, png_uint_32, png_get_PLTE, |
|
2179 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2180 png_colorp *palette, int *num_palette)); |
|
2181 |
|
2182 PNG_EXPORT(152, void, png_set_PLTE, |
|
2183 (png_structp png_ptr, png_infop info_ptr, |
|
2184 png_const_colorp palette, int num_palette)); |
|
2185 |
|
2186 #ifdef PNG_sBIT_SUPPORTED |
|
2187 PNG_EXPORT(153, png_uint_32, png_get_sBIT, |
|
2188 (png_const_structp png_ptr, png_infop info_ptr, |
|
2189 png_color_8p *sig_bit)); |
|
2190 #endif |
|
2191 |
|
2192 #ifdef PNG_sBIT_SUPPORTED |
|
2193 PNG_EXPORT(154, void, png_set_sBIT, |
|
2194 (png_structp png_ptr, png_infop info_ptr, png_const_color_8p sig_bit)); |
|
2195 #endif |
|
2196 |
|
2197 #ifdef PNG_sRGB_SUPPORTED |
|
2198 PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structp png_ptr, |
|
2199 png_const_infop info_ptr, int *file_srgb_intent)); |
|
2200 #endif |
|
2201 |
|
2202 #ifdef PNG_sRGB_SUPPORTED |
|
2203 PNG_EXPORT(156, void, png_set_sRGB, |
|
2204 (png_structp png_ptr, png_infop info_ptr, int srgb_intent)); |
|
2205 PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_structp png_ptr, |
|
2206 png_infop info_ptr, int srgb_intent)); |
|
2207 #endif |
|
2208 |
|
2209 #ifdef PNG_iCCP_SUPPORTED |
|
2210 PNG_EXPORT(158, png_uint_32, png_get_iCCP, |
|
2211 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2212 png_charpp name, int *compression_type, png_bytepp profile, |
|
2213 png_uint_32 *proflen)); |
|
2214 #endif |
|
2215 |
|
2216 #ifdef PNG_iCCP_SUPPORTED |
|
2217 PNG_EXPORT(159, void, png_set_iCCP, |
|
2218 (png_structp png_ptr, png_infop info_ptr, |
|
2219 png_const_charp name, int compression_type, png_const_bytep profile, |
|
2220 png_uint_32 proflen)); |
|
2221 #endif |
|
2222 |
|
2223 #ifdef PNG_sPLT_SUPPORTED |
|
2224 PNG_EXPORT(160, png_uint_32, png_get_sPLT, |
|
2225 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2226 png_sPLT_tpp entries)); |
|
2227 #endif |
|
2228 |
|
2229 #ifdef PNG_sPLT_SUPPORTED |
|
2230 PNG_EXPORT(161, void, png_set_sPLT, |
|
2231 (png_structp png_ptr, png_infop info_ptr, |
|
2232 png_const_sPLT_tp entries, int nentries)); |
|
2233 #endif |
|
2234 |
|
2235 #ifdef PNG_TEXT_SUPPORTED |
|
2236 /* png_get_text also returns the number of text chunks in *num_text */ |
|
2237 PNG_EXPORT(162, png_uint_32, png_get_text, |
|
2238 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2239 png_textp *text_ptr, int *num_text)); |
|
2240 #endif |
|
2241 |
|
2242 /* Note while png_set_text() will accept a structure whose text, |
|
2243 * language, and translated keywords are NULL pointers, the structure |
|
2244 * returned by png_get_text will always contain regular |
|
2245 * zero-terminated C strings. They might be empty strings but |
|
2246 * they will never be NULL pointers. |
|
2247 */ |
|
2248 |
|
2249 #ifdef PNG_TEXT_SUPPORTED |
|
2250 PNG_EXPORT(163, void, png_set_text, |
|
2251 (png_structp png_ptr, png_infop info_ptr, |
|
2252 png_const_textp text_ptr, int num_text)); |
|
2253 #endif |
|
2254 |
|
2255 #ifdef PNG_tIME_SUPPORTED |
|
2256 PNG_EXPORT(164, png_uint_32, png_get_tIME, |
|
2257 (png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time)); |
|
2258 #endif |
|
2259 |
|
2260 #ifdef PNG_tIME_SUPPORTED |
|
2261 PNG_EXPORT(165, void, png_set_tIME, |
|
2262 (png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time)); |
|
2263 #endif |
|
2264 |
|
2265 #ifdef PNG_tRNS_SUPPORTED |
|
2266 PNG_EXPORT(166, png_uint_32, png_get_tRNS, |
|
2267 (png_const_structp png_ptr, png_infop info_ptr, |
|
2268 png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)); |
|
2269 #endif |
|
2270 |
|
2271 #ifdef PNG_tRNS_SUPPORTED |
|
2272 PNG_EXPORT(167, void, png_set_tRNS, |
|
2273 (png_structp png_ptr, png_infop info_ptr, |
|
2274 png_const_bytep trans_alpha, int num_trans, |
|
2275 png_const_color_16p trans_color)); |
|
2276 #endif |
|
2277 |
|
2278 #ifdef PNG_sCAL_SUPPORTED |
|
2279 PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, |
|
2280 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2281 int *unit, double *width, double *height)); |
|
2282 #ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED |
|
2283 /* NOTE: this API is currently implemented using floating point arithmetic, |
|
2284 * consequently it can only be used on systems with floating point support. |
|
2285 * In any case the range of values supported by png_fixed_point is small and it |
|
2286 * is highly recommended that png_get_sCAL_s be used instead. |
|
2287 */ |
|
2288 PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, |
|
2289 (png_structp png_ptr, png_const_infop info_ptr, int *unit, |
|
2290 png_fixed_point *width, |
|
2291 png_fixed_point *height)); |
|
2292 #endif |
|
2293 PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, |
|
2294 (png_const_structp png_ptr, png_const_infop info_ptr, |
|
2295 int *unit, png_charpp swidth, png_charpp sheight)); |
|
2296 |
|
2297 PNG_FP_EXPORT(170, void, png_set_sCAL, |
|
2298 (png_structp png_ptr, png_infop info_ptr, |
|
2299 int unit, double width, double height)); |
|
2300 PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr, |
|
2301 png_infop info_ptr, int unit, png_fixed_point width, |
|
2302 png_fixed_point height)); |
|
2303 PNG_EXPORT(171, void, png_set_sCAL_s, |
|
2304 (png_structp png_ptr, png_infop info_ptr, |
|
2305 int unit, png_const_charp swidth, png_const_charp sheight)); |
|
2306 #endif /* PNG_sCAL_SUPPORTED */ |
|
2307 |
|
2308 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
|
2309 /* Provide a list of chunks and how they are to be handled, if the built-in |
|
2310 handling or default unknown chunk handling is not desired. Any chunks not |
|
2311 listed will be handled in the default manner. The IHDR and IEND chunks |
|
2312 must not be listed. |
|
2313 keep = 0: follow default behaviour |
|
2314 = 1: do not keep |
|
2315 = 2: keep only if safe-to-copy |
|
2316 = 3: keep even if unsafe-to-copy |
|
2317 */ |
|
2318 PNG_EXPORT(172, void, png_set_keep_unknown_chunks, |
|
2319 (png_structp png_ptr, int keep, |
|
2320 png_const_bytep chunk_list, int num_chunks)); |
|
2321 PNG_EXPORT(173, int, png_handle_as_unknown, (png_structp png_ptr, |
|
2322 png_const_bytep chunk_name)); |
|
2323 #endif |
|
2324 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED |
|
2325 PNG_EXPORT(174, void, png_set_unknown_chunks, (png_structp png_ptr, |
|
2326 png_infop info_ptr, png_const_unknown_chunkp unknowns, |
|
2327 int num_unknowns)); |
|
2328 PNG_EXPORT(175, void, png_set_unknown_chunk_location, |
|
2329 (png_structp png_ptr, png_infop info_ptr, int chunk, int location)); |
|
2330 PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structp png_ptr, |
|
2331 png_const_infop info_ptr, png_unknown_chunkpp entries)); |
|
2332 #endif |
|
2333 |
|
2334 /* Png_free_data() will turn off the "valid" flag for anything it frees. |
|
2335 * If you need to turn it off for a chunk that your application has freed, |
|
2336 * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); |
|
2337 */ |
|
2338 PNG_EXPORT(177, void, png_set_invalid, |
|
2339 (png_structp png_ptr, png_infop info_ptr, int mask)); |
|
2340 |
|
2341 #ifdef PNG_INFO_IMAGE_SUPPORTED |
|
2342 /* The "params" pointer is currently not used and is for future expansion. */ |
|
2343 PNG_EXPORT(178, void, png_read_png, (png_structp png_ptr, png_infop info_ptr, |
|
2344 int transforms, png_voidp params)); |
|
2345 PNG_EXPORT(179, void, png_write_png, (png_structp png_ptr, png_infop info_ptr, |
|
2346 int transforms, png_voidp params)); |
|
2347 #endif |
|
2348 |
|
2349 PNG_EXPORT(180, png_const_charp, png_get_copyright, |
|
2350 (png_const_structp png_ptr)); |
|
2351 PNG_EXPORT(181, png_const_charp, png_get_header_ver, |
|
2352 (png_const_structp png_ptr)); |
|
2353 PNG_EXPORT(182, png_const_charp, png_get_header_version, |
|
2354 (png_const_structp png_ptr)); |
|
2355 PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, |
|
2356 (png_const_structp png_ptr)); |
|
2357 |
|
2358 #ifdef PNG_MNG_FEATURES_SUPPORTED |
|
2359 PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structp png_ptr, |
|
2360 png_uint_32 mng_features_permitted)); |
|
2361 #endif |
|
2362 |
|
2363 /* For use in png_set_keep_unknown, added to version 1.2.6 */ |
|
2364 #define PNG_HANDLE_CHUNK_AS_DEFAULT 0 |
|
2365 #define PNG_HANDLE_CHUNK_NEVER 1 |
|
2366 #define PNG_HANDLE_CHUNK_IF_SAFE 2 |
|
2367 #define PNG_HANDLE_CHUNK_ALWAYS 3 |
|
2368 |
|
2369 /* Strip the prepended error numbers ("#nnn ") from error and warning |
|
2370 * messages before passing them to the error or warning handler. |
|
2371 */ |
|
2372 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
|
2373 PNG_EXPORT(185, void, png_set_strip_error_numbers, |
|
2374 (png_structp png_ptr, |
|
2375 png_uint_32 strip_mode)); |
|
2376 #endif |
|
2377 |
|
2378 /* Added in libpng-1.2.6 */ |
|
2379 #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
|
2380 PNG_EXPORT(186, void, png_set_user_limits, (png_structp png_ptr, |
|
2381 png_uint_32 user_width_max, png_uint_32 user_height_max)); |
|
2382 PNG_EXPORT(187, png_uint_32, png_get_user_width_max, |
|
2383 (png_const_structp png_ptr)); |
|
2384 PNG_EXPORT(188, png_uint_32, png_get_user_height_max, |
|
2385 (png_const_structp png_ptr)); |
|
2386 /* Added in libpng-1.4.0 */ |
|
2387 PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structp png_ptr, |
|
2388 png_uint_32 user_chunk_cache_max)); |
|
2389 PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, |
|
2390 (png_const_structp png_ptr)); |
|
2391 /* Added in libpng-1.4.1 */ |
|
2392 PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structp png_ptr, |
|
2393 png_alloc_size_t user_chunk_cache_max)); |
|
2394 PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, |
|
2395 (png_const_structp png_ptr)); |
|
2396 #endif |
|
2397 |
|
2398 #if defined(PNG_INCH_CONVERSIONS_SUPPORTED) |
|
2399 PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, |
|
2400 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2401 |
|
2402 PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, |
|
2403 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2404 |
|
2405 PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, |
|
2406 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2407 |
|
2408 PNG_FP_EXPORT(196, float, png_get_x_offset_inches, |
|
2409 (png_const_structp png_ptr, png_const_infop info_ptr)); |
|
2410 #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
|
2411 PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, |
|
2412 (png_structp png_ptr, png_const_infop info_ptr)); |
|
2413 #endif |
|
2414 |
|
2415 PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr, |
|
2416 png_const_infop info_ptr)); |
|
2417 #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
|
2418 PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, |
|
2419 (png_structp png_ptr, png_const_infop info_ptr)); |
|
2420 #endif |
|
2421 |
|
2422 # ifdef PNG_pHYs_SUPPORTED |
|
2423 PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structp png_ptr, |
|
2424 png_const_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
|
2425 int *unit_type)); |
|
2426 # endif /* PNG_pHYs_SUPPORTED */ |
|
2427 #endif /* PNG_INCH_CONVERSIONS_SUPPORTED */ |
|
2428 |
|
2429 /* Added in libpng-1.4.0 */ |
|
2430 #ifdef PNG_IO_STATE_SUPPORTED |
|
2431 PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_structp png_ptr)); |
|
2432 |
|
2433 PNG_EXPORTA(200, png_const_bytep, png_get_io_chunk_name, |
|
2434 (png_structp png_ptr), PNG_DEPRECATED); |
|
2435 PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, |
|
2436 (png_const_structp png_ptr)); |
|
2437 |
|
2438 /* The flags returned by png_get_io_state() are the following: */ |
|
2439 # define PNG_IO_NONE 0x0000 /* no I/O at this moment */ |
|
2440 # define PNG_IO_READING 0x0001 /* currently reading */ |
|
2441 # define PNG_IO_WRITING 0x0002 /* currently writing */ |
|
2442 # define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ |
|
2443 # define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ |
|
2444 # define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ |
|
2445 # define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ |
|
2446 # define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ |
|
2447 # define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ |
|
2448 #endif /* ?PNG_IO_STATE_SUPPORTED */ |
|
2449 |
|
2450 /* Interlace support. The following macros are always defined so that if |
|
2451 * libpng interlace handling is turned off the macros may be used to handle |
|
2452 * interlaced images within the application. |
|
2453 */ |
|
2454 #define PNG_INTERLACE_ADAM7_PASSES 7 |
|
2455 |
|
2456 /* Two macros to return the first row and first column of the original, |
|
2457 * full, image which appears in a given pass. 'pass' is in the range 0 |
|
2458 * to 6 and the result is in the range 0 to 7. |
|
2459 */ |
|
2460 #define PNG_PASS_START_ROW(pass) (((1U&~(pass))<<(3-((pass)>>1)))&7) |
|
2461 #define PNG_PASS_START_COL(pass) (((1U& (pass))<<(3-(((pass)+1)>>1)))&7) |
|
2462 |
|
2463 /* Two macros to help evaluate the number of rows or columns in each |
|
2464 * pass. This is expressed as a shift - effectively log2 of the number or |
|
2465 * rows or columns in each 8x8 tile of the original image. |
|
2466 */ |
|
2467 #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) |
|
2468 #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) |
|
2469 |
|
2470 /* Hence two macros to determine the number of rows or columns in a given |
|
2471 * pass of an image given its height or width. In fact these macros may |
|
2472 * return non-zero even though the sub-image is empty, because the other |
|
2473 * dimension may be empty for a small image. |
|
2474 */ |
|
2475 #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ |
|
2476 -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) |
|
2477 #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ |
|
2478 -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) |
|
2479 |
|
2480 /* For the reader row callbacks (both progressive and sequential) it is |
|
2481 * necessary to find the row in the output image given a row in an interlaced |
|
2482 * image, so two more macros: |
|
2483 */ |
|
2484 #define PNG_ROW_FROM_PASS_ROW(yIn, pass) \ |
|
2485 (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) |
|
2486 #define PNG_COL_FROM_PASS_COL(xIn, pass) \ |
|
2487 (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) |
|
2488 |
|
2489 /* Two macros which return a boolean (0 or 1) saying whether the given row |
|
2490 * or column is in a particular pass. These use a common utility macro that |
|
2491 * returns a mask for a given pass - the offset 'off' selects the row or |
|
2492 * column version. The mask has the appropriate bit set for each column in |
|
2493 * the tile. |
|
2494 */ |
|
2495 #define PNG_PASS_MASK(pass,off) ( \ |
|
2496 ((0x110145AFU>>(((7-(off))-(pass))<<2)) & 0xFU) | \ |
|
2497 ((0x01145AF0U>>(((7-(off))-(pass))<<2)) & 0xF0U)) |
|
2498 |
|
2499 #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ |
|
2500 ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) |
|
2501 #define PNG_COL_IN_INTERLACE_PASS(x, pass) \ |
|
2502 ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) |
|
2503 |
|
2504 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED |
|
2505 /* With these routines we avoid an integer divide, which will be slower on |
|
2506 * most machines. However, it does take more operations than the corresponding |
|
2507 * divide method, so it may be slower on a few RISC systems. There are two |
|
2508 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. |
|
2509 * |
|
2510 * Note that the rounding factors are NOT supposed to be the same! 128 and |
|
2511 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the |
|
2512 * standard method. |
|
2513 * |
|
2514 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] |
|
2515 */ |
|
2516 |
|
2517 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ |
|
2518 |
|
2519 # define png_composite(composite, fg, alpha, bg) \ |
|
2520 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ |
|
2521 * (png_uint_16)(alpha) \ |
|
2522 + (png_uint_16)(bg)*(png_uint_16)(255 \ |
|
2523 - (png_uint_16)(alpha)) + (png_uint_16)128); \ |
|
2524 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } |
|
2525 |
|
2526 # define png_composite_16(composite, fg, alpha, bg) \ |
|
2527 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ |
|
2528 * (png_uint_32)(alpha) \ |
|
2529 + (png_uint_32)(bg)*(png_uint_32)(65535L \ |
|
2530 - (png_uint_32)(alpha)) + (png_uint_32)32768L); \ |
|
2531 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } |
|
2532 |
|
2533 #else /* Standard method using integer division */ |
|
2534 |
|
2535 # define png_composite(composite, fg, alpha, bg) \ |
|
2536 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ |
|
2537 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ |
|
2538 (png_uint_16)127) / 255) |
|
2539 |
|
2540 # define png_composite_16(composite, fg, alpha, bg) \ |
|
2541 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ |
|
2542 (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \ |
|
2543 (png_uint_32)32767) / (png_uint_32)65535L) |
|
2544 #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */ |
|
2545 |
|
2546 #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED |
|
2547 PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); |
|
2548 PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); |
|
2549 PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); |
|
2550 #endif |
|
2551 |
|
2552 PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_structp png_ptr, |
|
2553 png_const_bytep buf)); |
|
2554 /* No png_get_int_16 -- may be added if there's a real need for it. */ |
|
2555 |
|
2556 /* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ |
|
2557 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
|
2558 PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); |
|
2559 #endif |
|
2560 #ifdef PNG_SAVE_INT_32_SUPPORTED |
|
2561 PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); |
|
2562 #endif |
|
2563 |
|
2564 /* Place a 16-bit number into a buffer in PNG byte order. |
|
2565 * The parameter is declared unsigned int, not png_uint_16, |
|
2566 * just to avoid potential problems on pre-ANSI C compilers. |
|
2567 */ |
|
2568 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
|
2569 PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); |
|
2570 /* No png_save_int_16 -- may be added if there's a real need for it. */ |
|
2571 #endif |
|
2572 |
|
2573 #ifdef PNG_USE_READ_MACROS |
|
2574 /* Inline macros to do direct reads of bytes from the input buffer. |
|
2575 * The png_get_int_32() routine assumes we are using two's complement |
|
2576 * format for negative values, which is almost certainly true. |
|
2577 */ |
|
2578 # define png_get_uint_32(buf) \ |
|
2579 (((png_uint_32)(*(buf)) << 24) + \ |
|
2580 ((png_uint_32)(*((buf) + 1)) << 16) + \ |
|
2581 ((png_uint_32)(*((buf) + 2)) << 8) + \ |
|
2582 ((png_uint_32)(*((buf) + 3)))) |
|
2583 |
|
2584 /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the |
|
2585 * function) incorrectly returned a value of type png_uint_32. |
|
2586 */ |
|
2587 # define png_get_uint_16(buf) \ |
|
2588 ((png_uint_16) \ |
|
2589 (((unsigned int)(*(buf)) << 8) + \ |
|
2590 ((unsigned int)(*((buf) + 1))))) |
|
2591 |
|
2592 # define png_get_int_32(buf) \ |
|
2593 ((png_int_32)((*(buf) & 0x80) \ |
|
2594 ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \ |
|
2595 : (png_int_32)png_get_uint_32(buf))) |
|
2596 #endif |
|
2597 |
|
2598 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project |
|
2599 * defs |
|
2600 */ |
|
2601 |
|
2602 /* The last ordinal number (this is the *last* one already used; the next |
|
2603 * one to use is one more than this.) Maintainer, remember to add an entry to |
|
2604 * scripts/symbols.def as well. |
|
2605 */ |
|
2606 #ifdef PNG_EXPORT_LAST_ORDINAL |
|
2607 PNG_EXPORT_LAST_ORDINAL(229); |
|
2608 #endif |
|
2609 |
|
2610 #ifdef __cplusplus |
|
2611 } |
|
2612 #endif |
|
2613 |
|
2614 #endif /* PNG_VERSION_INFO_ONLY */ |
|
2615 /* Do not put anything past this line */ |
|
2616 #endif /* PNG_H */ |