1 2 /* png.h - header file for PNG reference library 3 * 4 * libpng version 1.6.3 - July 18, 2013 5 * Copyright (c) 1998-2013 Glenn Randers-Pehrson 6 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) 7 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) 8 * 9 * This code is released under the libpng license (See LICENSE, below) 10 * 11 * Authors and maintainers: 12 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat 13 * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger 14 * libpng versions 0.97, January 1998, through 1.6.3 - July 18, 2013: Glenn 15 * See also "Contributing Authors", below. 16 * 17 * Note about libpng version numbers: 18 * 19 * Due to various miscommunications, unforeseen code incompatibilities 20 * and occasional factors outside the authors' control, version numbering 21 * on the library has not always been consistent and straightforward. 22 * The following table summarizes matters since version 0.89c, which was 23 * the first widely used release: 24 * 25 * source png.h png.h shared-lib 26 * version string int version 27 * ------- ------ ----- ---------- 28 * 0.89c "1.0 beta 3" 0.89 89 1.0.89 29 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] 30 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] 31 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] 32 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] 33 * 0.97c 0.97 97 2.0.97 34 * 0.98 0.98 98 2.0.98 35 * 0.99 0.99 98 2.0.99 36 * 0.99a-m 0.99 99 2.0.99 37 * 1.00 1.00 100 2.1.0 [100 should be 10000] 38 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] 39 * 1.0.1 png.h string is 10001 2.1.0 40 * 1.0.1a-e identical to the 10002 from here on, the shared library 41 * 1.0.2 source version) 10002 is 2.V where V is the source code 42 * 1.0.2a-b 10003 version, except as noted. 43 * 1.0.3 10003 44 * 1.0.3a-d 10004 45 * 1.0.4 10004 46 * 1.0.4a-f 10005 47 * 1.0.5 (+ 2 patches) 10005 48 * 1.0.5a-d 10006 49 * 1.0.5e-r 10100 (not source compatible) 50 * 1.0.5s-v 10006 (not binary compatible) 51 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) 52 * 1.0.6d-f 10007 (still binary incompatible) 53 * 1.0.6g 10007 54 * 1.0.6h 10007 10.6h (testing xy.z so-numbering) 55 * 1.0.6i 10007 10.6i 56 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) 57 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) 58 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) 59 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) 60 * 1.0.7 1 10007 (still compatible) 61 * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4 62 * 1.0.8rc1 1 10008 2.1.0.8rc1 63 * 1.0.8 1 10008 2.1.0.8 64 * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6 65 * 1.0.9rc1 1 10009 2.1.0.9rc1 66 * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10 67 * 1.0.9rc2 1 10009 2.1.0.9rc2 68 * 1.0.9 1 10009 2.1.0.9 69 * 1.0.10beta1 1 10010 2.1.0.10beta1 70 * 1.0.10rc1 1 10010 2.1.0.10rc1 71 * 1.0.10 1 10010 2.1.0.10 72 * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3 73 * 1.0.11rc1 1 10011 2.1.0.11rc1 74 * 1.0.11 1 10011 2.1.0.11 75 * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2 76 * 1.0.12rc1 2 10012 2.1.0.12rc1 77 * 1.0.12 2 10012 2.1.0.12 78 * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned) 79 * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2 80 * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5 81 * 1.2.0rc1 3 10200 3.1.2.0rc1 82 * 1.2.0 3 10200 3.1.2.0 83 * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4 84 * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2 85 * 1.2.1 3 10201 3.1.2.1 86 * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6 87 * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1 88 * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1 89 * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1 90 * 1.0.13 10 10013 10.so.0.1.0.13 91 * 1.2.2 12 10202 12.so.0.1.2.2 92 * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6 93 * 1.2.3 12 10203 12.so.0.1.2.3 94 * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3 95 * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1 96 * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1 97 * 1.0.14 10 10014 10.so.0.1.0.14 98 * 1.2.4 13 10204 12.so.0.1.2.4 99 * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2 100 * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3 101 * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3 102 * 1.0.15 10 10015 10.so.0.1.0.15 103 * 1.2.5 13 10205 12.so.0.1.2.5 104 * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4 105 * 1.0.16 10 10016 10.so.0.1.0.16 106 * 1.2.6 13 10206 12.so.0.1.2.6 107 * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2 108 * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1 109 * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1 110 * 1.0.17 10 10017 12.so.0.1.0.17 111 * 1.2.7 13 10207 12.so.0.1.2.7 112 * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5 113 * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5 114 * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5 115 * 1.0.18 10 10018 12.so.0.1.0.18 116 * 1.2.8 13 10208 12.so.0.1.2.8 117 * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3 118 * 1.2.9beta4-11 13 10209 12.so.0.9[.0] 119 * 1.2.9rc1 13 10209 12.so.0.9[.0] 120 * 1.2.9 13 10209 12.so.0.9[.0] 121 * 1.2.10beta1-7 13 10210 12.so.0.10[.0] 122 * 1.2.10rc1-2 13 10210 12.so.0.10[.0] 123 * 1.2.10 13 10210 12.so.0.10[.0] 124 * 1.4.0beta1-5 14 10400 14.so.0.0[.0] 125 * 1.2.11beta1-4 13 10211 12.so.0.11[.0] 126 * 1.4.0beta7-8 14 10400 14.so.0.0[.0] 127 * 1.2.11 13 10211 12.so.0.11[.0] 128 * 1.2.12 13 10212 12.so.0.12[.0] 129 * 1.4.0beta9-14 14 10400 14.so.0.0[.0] 130 * 1.2.13 13 10213 12.so.0.13[.0] 131 * 1.4.0beta15-36 14 10400 14.so.0.0[.0] 132 * 1.4.0beta37-87 14 10400 14.so.14.0[.0] 133 * 1.4.0rc01 14 10400 14.so.14.0[.0] 134 * 1.4.0beta88-109 14 10400 14.so.14.0[.0] 135 * 1.4.0rc02-08 14 10400 14.so.14.0[.0] 136 * 1.4.0 14 10400 14.so.14.0[.0] 137 * 1.4.1beta01-03 14 10401 14.so.14.1[.0] 138 * 1.4.1rc01 14 10401 14.so.14.1[.0] 139 * 1.4.1beta04-12 14 10401 14.so.14.1[.0] 140 * 1.4.1 14 10401 14.so.14.1[.0] 141 * 1.4.2 14 10402 14.so.14.2[.0] 142 * 1.4.3 14 10403 14.so.14.3[.0] 143 * 1.4.4 14 10404 14.so.14.4[.0] 144 * 1.5.0beta01-58 15 10500 15.so.15.0[.0] 145 * 1.5.0rc01-07 15 10500 15.so.15.0[.0] 146 * 1.5.0 15 10500 15.so.15.0[.0] 147 * 1.5.1beta01-11 15 10501 15.so.15.1[.0] 148 * 1.5.1rc01-02 15 10501 15.so.15.1[.0] 149 * 1.5.1 15 10501 15.so.15.1[.0] 150 * 1.5.2beta01-03 15 10502 15.so.15.2[.0] 151 * 1.5.2rc01-03 15 10502 15.so.15.2[.0] 152 * 1.5.2 15 10502 15.so.15.2[.0] 153 * 1.5.3beta01-10 15 10503 15.so.15.3[.0] 154 * 1.5.3rc01-02 15 10503 15.so.15.3[.0] 155 * 1.5.3beta11 15 10503 15.so.15.3[.0] 156 * 1.5.3 [omitted] 157 * 1.5.4beta01-08 15 10504 15.so.15.4[.0] 158 * 1.5.4rc01 15 10504 15.so.15.4[.0] 159 * 1.5.4 15 10504 15.so.15.4[.0] 160 * 1.5.5beta01-08 15 10505 15.so.15.5[.0] 161 * 1.5.5rc01 15 10505 15.so.15.5[.0] 162 * 1.5.5 15 10505 15.so.15.5[.0] 163 * 1.5.6beta01-07 15 10506 15.so.15.6[.0] 164 * 1.5.6rc01-03 15 10506 15.so.15.6[.0] 165 * 1.5.6 15 10506 15.so.15.6[.0] 166 * 1.5.7beta01-05 15 10507 15.so.15.7[.0] 167 * 1.5.7rc01-03 15 10507 15.so.15.7[.0] 168 * 1.5.7 15 10507 15.so.15.7[.0] 169 * 1.6.0beta01-40 16 10600 16.so.16.0[.0] 170 * 1.6.0rc01-08 16 10600 16.so.16.0[.0] 171 * 1.6.0 16 10600 16.so.16.0[.0] 172 * 1.6.1beta01-09 16 10601 16.so.16.1[.0] 173 * 1.6.1rc01 16 10601 16.so.16.1[.0] 174 * 1.6.1 16 10601 16.so.16.1[.0] 175 * 1.6.2beta01 16 10602 16.so.16.2[.0] 176 * 1.6.2rc01-06 16 10602 16.so.16.2[.0] 177 * 1.6.2 16 10602 16.so.16.2[.0] 178 * 1.6.3beta01-11 16 10603 16.so.16.3[.0] 179 * 1.6.3rc01 16 10603 16.so.16.3[.0] 180 * 1.6.3 16 10603 16.so.16.3[.0] 181 * 182 * Henceforth the source version will match the shared-library major 183 * and minor numbers; the shared-library major version number will be 184 * used for changes in backward compatibility, as it is intended. The 185 * PNG_LIBPNG_VER macro, which is not used within libpng but is available 186 * for applications, is an unsigned integer of the form xyyzz corresponding 187 * to the source version x.y.z (leading zeros in y and z). Beta versions 188 * were given the previous public release number plus a letter, until 189 * version 1.0.6j; from then on they were given the upcoming public 190 * release number plus "betaNN" or "rcNN". 191 * 192 * Binary incompatibility exists only when applications make direct access 193 * to the info_ptr or png_ptr members through png.h, and the compiled 194 * application is loaded with a different version of the library. 195 * 196 * DLLNUM will change each time there are forward or backward changes 197 * in binary compatibility (e.g., when a new feature is added). 198 * 199 * See libpng-manual.txt or libpng.3 for more information. The PNG 200 * specification is available as a W3C Recommendation and as an ISO 201 * Specification, <http://www.w3.org/TR/2003/REC-PNG-20031110/ 202 */ 203 204 /* 205 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE: 206 * 207 * If you modify libpng you may insert additional notices immediately following 208 * this sentence. 209 * 210 * This code is released under the libpng license. 211 * 212 * libpng versions 1.2.6, August 15, 2004, through 1.6.3, July 18, 2013, are 213 * Copyright (c) 2004, 2006-2013 Glenn Randers-Pehrson, and are 214 * distributed according to the same disclaimer and license as libpng-1.2.5 215 * with the following individual added to the list of Contributing Authors: 216 * 217 * Cosmin Truta 218 * 219 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are 220 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are 221 * distributed according to the same disclaimer and license as libpng-1.0.6 222 * with the following individuals added to the list of Contributing Authors: 223 * 224 * Simon-Pierre Cadieux 225 * Eric S. Raymond 226 * Gilles Vollant 227 * 228 * and with the following additions to the disclaimer: 229 * 230 * There is no warranty against interference with your enjoyment of the 231 * library or against infringement. There is no warranty that our 232 * efforts or the library will fulfill any of your particular purposes 233 * or needs. This library is provided with all faults, and the entire 234 * risk of satisfactory quality, performance, accuracy, and effort is with 235 * the user. 236 * 237 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are 238 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are 239 * distributed according to the same disclaimer and license as libpng-0.96, 240 * with the following individuals added to the list of Contributing Authors: 241 * 242 * Tom Lane 243 * Glenn Randers-Pehrson 244 * Willem van Schaik 245 * 246 * libpng versions 0.89, June 1996, through 0.96, May 1997, are 247 * Copyright (c) 1996, 1997 Andreas Dilger 248 * Distributed according to the same disclaimer and license as libpng-0.88, 249 * with the following individuals added to the list of Contributing Authors: 250 * 251 * John Bowler 252 * Kevin Bracey 253 * Sam Bushell 254 * Magnus Holmgren 255 * Greg Roelofs 256 * Tom Tanner 257 * 258 * libpng versions 0.5, May 1995, through 0.88, January 1996, are 259 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. 260 * 261 * For the purposes of this copyright and license, "Contributing Authors" 262 * is defined as the following set of individuals: 263 * 264 * Andreas Dilger 265 * Dave Martindale 266 * Guy Eric Schalnat 267 * Paul Schmidt 268 * Tim Wegner 269 * 270 * The PNG Reference Library is supplied "AS IS". The Contributing Authors 271 * and Group 42, Inc. disclaim all warranties, expressed or implied, 272 * including, without limitation, the warranties of merchantability and of 273 * fitness for any purpose. The Contributing Authors and Group 42, Inc. 274 * assume no liability for direct, indirect, incidental, special, exemplary, 275 * or consequential damages, which may result from the use of the PNG 276 * Reference Library, even if advised of the possibility of such damage. 277 * 278 * Permission is hereby granted to use, copy, modify, and distribute this 279 * source code, or portions hereof, for any purpose, without fee, subject 280 * to the following restrictions: 281 * 282 * 1. The origin of this source code must not be misrepresented. 283 * 284 * 2. Altered versions must be plainly marked as such and must not 285 * be misrepresented as being the original source. 286 * 287 * 3. This Copyright notice may not be removed or altered from 288 * any source or altered source distribution. 289 * 290 * The Contributing Authors and Group 42, Inc. specifically permit, without 291 * fee, and encourage the use of this source code as a component to 292 * supporting the PNG file format in commercial products. If you use this 293 * source code in a product, acknowledgment is not required but would be 294 * appreciated. 295 */ 296 297 /* 298 * A "png_get_copyright" function is available, for convenient use in "about" 299 * boxes and the like: 300 * 301 * printf("%s", png_get_copyright(NULL)); 302 * 303 * Also, the PNG logo (in PNG format, of course) is supplied in the 304 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). 305 */ 306 307 /* 308 * Libpng is OSI Certified Open Source Software. OSI Certified is a 309 * certification mark of the Open Source Initiative. 310 */ 311 312 /* 313 * The contributing authors would like to thank all those who helped 314 * with testing, bug fixes, and patience. This wouldn't have been 315 * possible without all of you. 316 * 317 * Thanks to Frank J. T. Wojcik for helping with the documentation. 318 */ 319 320 /* 321 * Y2K compliance in libpng: 322 * ========================= 323 * 324 * July 18, 2013 325 * 326 * Since the PNG Development group is an ad-hoc body, we can't make 327 * an official declaration. 328 * 329 * This is your unofficial assurance that libpng from version 0.71 and 330 * upward through 1.6.3 are Y2K compliant. It is my belief that 331 * earlier versions were also Y2K compliant. 332 * 333 * Libpng only has two year fields. One is a 2-byte unsigned integer 334 * that will hold years up to 65535. The other, which is deprecated, 335 * holds the date in text format, and will hold years up to 9999. 336 * 337 * The integer is 338 * "png_uint_16 year" in png_time_struct. 339 * 340 * The string is 341 * "char time_buffer[29]" in png_struct. This is no longer used 342 * in libpng-1.6.x and will be removed from libpng-1.7.0. 343 * 344 * There are seven time-related functions: 345 * png.c: png_convert_to_rfc_1123_buffer() in png.c 346 * (formerly png_convert_to_rfc_1123() prior to libpng-1.5.x and 347 * png_convert_to_rfc_1152() in error prior to libpng-0.98) 348 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c 349 * png_convert_from_time_t() in pngwrite.c 350 * png_get_tIME() in pngget.c 351 * png_handle_tIME() in pngrutil.c, called in pngread.c 352 * png_set_tIME() in pngset.c 353 * png_write_tIME() in pngwutil.c, called in pngwrite.c 354 * 355 * All handle dates properly in a Y2K environment. The 356 * png_convert_from_time_t() function calls gmtime() to convert from system 357 * clock time, which returns (year - 1900), which we properly convert to 358 * the full 4-digit year. There is a possibility that libpng applications 359 * are not passing 4-digit years into the png_convert_to_rfc_1123_buffer() 360 * function, or that they are incorrectly passing only a 2-digit year 361 * instead of "year - 1900" into the png_convert_from_struct_tm() function, 362 * but this is not under our control. The libpng documentation has always 363 * stated that it works with 4-digit years, and the APIs have been 364 * documented as such. 365 * 366 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned 367 * integer to hold the year, and can hold years as large as 65535. 368 * 369 * zlib, upon which libpng depends, is also Y2K compliant. It contains 370 * no date-related code. 371 * 372 * Glenn Randers-Pehrson 373 * libpng maintainer 374 * PNG Development Group 375 */ 376 377 #ifndef PNG_H 378 #define PNG_H 379 380 /* This is not the place to learn how to use libpng. The file libpng-manual.txt 381 * describes how to use libpng, and the file example.c summarizes it 382 * with some code on which to build. This file is useful for looking 383 * at the actual function definitions and structure components. 384 * 385 * If you just need to read a PNG file and don't want to read the documentation 386 * skip to the end of this file and read the section entitled 'simplified API'. 387 */ 388 389 /* Sunliang.liu add 20100319 for avoid name conflict. */ 390 #define png_set_sig_bytes FOXIT_png_set_sig_bytes 391 #define png_sig_cmp FOXIT_png_sig_cmp 392 #define png_create_info_struct FOXIT_png_create_info_struct 393 #define png_destroy_info_struct FOXIT_png_destroy_info_struct 394 #define png_info_init_3 FOXIT_png_info_init_3 395 #define png_data_freer FOXIT_png_data_freer 396 #define png_free_data FOXIT_png_free_data 397 #define png_info_destroy FOXIT_png_info_destroy 398 #define png_get_io_ptr FOXIT_png_get_io_ptr 399 #define png_init_io FOXIT_png_init_io 400 #define png_convert_to_rfc1123 FOXIT_png_convert_to_rfc1123 401 #define png_get_copyright FOXIT_png_get_copyright 402 #define png_get_libpng_ver FOXIT_png_get_libpng_ver 403 #define png_get_header_ver FOXIT_png_get_header_ver 404 #define png_get_header_version FOXIT_png_get_header_version 405 #define png_handle_as_unknown FOXIT_png_handle_as_unknown 406 #define png_reset_zstream FOXIT_png_reset_zstream 407 #define png_access_version_number FOXIT_png_access_version_number 408 #define png_mmx_support FOXIT_png_mmx_support 409 #define png_create_read_struct FOXIT_png_create_read_struct 410 #define png_create_read_struct_2 FOXIT_png_create_read_struct_2 411 #define png_create_write_struct FOXIT_png_create_write_struct 412 #define png_create_write_struct_2 FOXIT_png_create_write_struct_2 413 #define png_get_compression_buffer_size FOXIT_png_get_compression_buffer_size 414 #define png_set_compression_buffer_size FOXIT_png_set_compression_buffer_size 415 #define png_set_longjmp_fn FOXIT_png_set_longjmp_fn 416 #define png_longjmp FOXIT_png_longjmp 417 #define png_write_sig FOXIT_png_write_sig 418 #define png_write_chunk FOXIT_png_write_chunk 419 #define png_write_chunk_start FOXIT_png_write_chunk_start 420 #define png_write_chunk_data FOXIT_png_write_chunk_data 421 #define png_write_chunk_end FOXIT_png_write_chunk_end 422 #define png_write_info_before_PLTE FOXIT_png_write_info_before_PLTE 423 #define png_write_info FOXIT_png_write_info 424 #define png_read_info FOXIT_png_read_info 425 #define png_convert_to_rfc1123_buffer FOXIT_png_convert_to_rfc1123_buffer 426 #define png_convert_from_struct_tm FOXIT_png_convert_from_struct_tm 427 #define png_convert_from_time_t FOXIT_png_convert_from_time_t 428 #define png_set_expand FOXIT_png_set_expand 429 #define png_set_expand_gray_1_2_4_to_8 FOXIT_png_set_expand_gray_1_2_4_to_8 430 #define png_set_palette_to_rgb FOXIT_png_set_palette_to_rgb 431 #define png_set_tRNS_to_alpha FOXIT_png_set_tRNS_to_alpha 432 #define png_set_expand_16 FOXIT_png_set_expand_16 433 #define png_set_bgr FOXIT_png_set_bgr 434 #define png_set_gray_to_rgb FOXIT_png_set_gray_to_rgb 435 #define png_set_rgb_to_gray FOXIT_png_set_rgb_to_gray 436 #define png_set_rgb_to_gray_fixed FOXIT_png_set_rgb_to_gray_fixed 437 #define png_get_rgb_to_gray_status FOXIT_png_get_rgb_to_gray_status 438 #define png_build_grayscale_palette FOXIT_png_build_grayscale_palette 439 #define png_set_alpha_mode FOXIT_png_set_alpha_mode 440 #define png_set_alpha_mode_fixed FOXIT_png_set_alpha_mode_fixed 441 #define png_set_strip_alpha FOXIT_png_set_strip_alpha 442 #define png_set_swap_alpha FOXIT_png_set_swap_alpha 443 #define png_set_invert_alpha FOXIT_png_set_invert_alpha 444 #define png_set_filler FOXIT_png_set_filler 445 #define png_set_add_alpha FOXIT_png_set_add_alpha 446 #define png_set_swap FOXIT_png_set_swap 447 #define png_set_packing FOXIT_png_set_packing 448 #define png_set_packswap FOXIT_png_set_packswap 449 #define png_set_shift FOXIT_png_set_shift 450 #define png_set_interlace_handling FOXIT_png_set_interlace_handling 451 #define png_set_invert_mono FOXIT_png_set_invert_mono 452 #define png_set_background FOXIT_png_set_background 453 #define png_set_background_fixed FOXIT_png_set_background_fixed 454 #define png_set_scale_16 FOXIT_png_set_scale_16 455 #define png_set_quantize FOXIT_png_set_quantize 456 #define png_set_gamma FOXIT_png_set_gamma 457 #define png_set_gamma_fixed FOXIT_png_set_gamma_fixed 458 #define png_set_flush FOXIT_png_set_flush 459 #define png_write_flush FOXIT_png_write_flush 460 #define png_start_read_image FOXIT_png_start_read_image 461 #define png_read_update_info FOXIT_png_read_update_info 462 #define png_read_rows FOXIT_png_read_rows 463 #define png_read_row FOXIT_png_read_row 464 #define png_read_image FOXIT_png_read_image 465 #define png_write_row FOXIT_png_write_row 466 #define png_write_rows FOXIT_png_write_rows 467 #define png_write_image FOXIT_png_write_image 468 #define png_write_end FOXIT_png_write_end 469 #define png_read_end FOXIT_png_read_end 470 #define png_destroy_read_struct FOXIT_png_destroy_read_struct 471 #define png_destroy_write_struct FOXIT_png_destroy_write_struct 472 #define png_set_crc_action FOXIT_png_set_crc_action 473 #define png_set_filter FOXIT_png_set_filter 474 #define png_set_filter_heuristics FOXIT_png_set_filter_heuristics 475 #define png_set_filter_heuristics_fixed FOXIT_png_set_filter_heuristics_fixed 476 #define png_set_compression_level FOXIT_png_set_compression_level 477 #define png_set_compression_mem_level FOXIT_png_set_compression_mem_level 478 #define png_set_compression_strategy FOXIT_png_set_compression_strategy 479 #define png_set_compression_window_bits FOXIT_png_set_compression_window_bits 480 #define png_set_compression_method FOXIT_png_set_compression_method 481 #define png_set_text_compression_level FOXIT_png_set_text_compression_level 482 #define png_set_text_compression_mem_level FOXIT_png_set_text_compression_mem_level 483 #define png_set_text_compression_strategy FOXIT_png_set_text_compression_strategy 484 #define png_set_text_compression_window_bits FOXIT_png_set_text_compression_window_bits 485 #define png_set_text_compression_method FOXIT_png_set_text_compression_method 486 #define png_set_error_fn FOXIT_png_set_error_fn 487 #define png_get_error_ptr FOXIT_png_get_error_ptr 488 #define png_set_write_fn FOXIT_png_set_write_fn 489 #define png_set_read_fn FOXIT_png_set_read_fn 490 #define png_set_read_status_fn FOXIT_png_set_read_status_fn 491 #define png_set_write_status_fn FOXIT_png_set_write_status_fn 492 #define png_set_read_user_transform_fn FOXIT_png_set_read_user_transform_fn 493 #define png_set_write_user_transform_fn FOXIT_png_set_write_user_transform_fn 494 #define png_set_user_transform_info FOXIT_png_set_user_transform_info 495 #define png_get_user_transform_ptr FOXIT_png_get_user_transform_ptr 496 #define png_get_current_row_number FOXIT_png_get_current_row_number 497 #define png_get_current_pass_number FOXIT_png_get_current_pass_number 498 #define png_set_read_user_chunk_fn FOXIT_png_set_read_user_chunk_fn 499 #define png_get_user_chunk_ptr FOXIT_png_get_user_chunk_ptr 500 #define png_set_progressive_read_fn FOXIT_png_set_progressive_read_fn 501 #define png_get_progressive_ptr FOXIT_png_get_progressive_ptr 502 #define png_process_data FOXIT_png_process_data 503 #define png_process_data_pause FOXIT_png_process_data_pause 504 #define png_process_data_skip FOXIT_png_process_data_skip 505 #define png_progressive_combine_row FOXIT_png_progressive_combine_row 506 #define png_calloc FOXIT_png_calloc 507 #define png_error FOXIT_png_error 508 #define png_chunk_error FOXIT_png_chunk_error 509 #define png_err FOXIT_png_err 510 #define png_warning FOXIT_png_warning 511 #define png_chunk_warning FOXIT_png_chunk_warning 512 #define png_benign_error FOXIT_png_benign_error 513 #define png_chunk_benign_error FOXIT_png_chunk_benign_error 514 #define png_set_benign_errors FOXIT_png_set_benign_errors 515 #define png_get_valid FOXIT_png_get_valid 516 #define png_get_rowbytes FOXIT_png_get_rowbytes 517 #define png_get_rows FOXIT_png_get_rows 518 #define png_set_rows FOXIT_png_set_rows 519 #define png_get_channels FOXIT_png_get_channels 520 #define png_get_image_width FOXIT_png_get_image_width 521 #define png_get_image_height FOXIT_png_get_image_height 522 #define png_get_bit_depth FOXIT_png_get_bit_depth 523 #define png_get_color_type FOXIT_png_get_color_type 524 #define png_get_filter_type FOXIT_png_get_filter_type 525 #define png_get_interlace_type FOXIT_png_get_interlace_type 526 #define png_get_compression_type FOXIT_png_get_compression_type 527 #define png_get_pixels_per_meter FOXIT_png_get_pixels_per_meter 528 #define png_get_x_pixels_per_meter FOXIT_png_get_x_pixels_per_meter 529 #define png_get_y_pixels_per_meter FOXIT_png_get_y_pixels_per_meter 530 #define png_get_pixel_aspect_ratio FOXIT_png_get_pixel_aspect_ratio 531 #define png_get_pixel_aspect_ratio_fixed FOXIT_png_get_pixel_aspect_ratio_fixed 532 #define png_get_x_offset_pixels FOXIT_png_get_x_offset_pixels 533 #define png_get_y_offset_pixels FOXIT_png_get_y_offset_pixels 534 #define png_get_x_offset_microns FOXIT_png_get_x_offset_microns 535 #define png_get_y_offset_microns FOXIT_png_get_y_offset_microns 536 #define png_get_signature FOXIT_png_get_signature 537 #define png_get_bKGD FOXIT_png_get_bKGD 538 #define png_set_bKGD FOXIT_png_set_bKGD 539 #define png_get_cHRM FOXIT_png_get_cHRM 540 #define png_get_cHRM_XYZ FOXIT_png_get_cHRM_XYZ 541 #define png_get_cHRM_fixed FOXIT_png_get_cHRM_fixed 542 #define png_get_cHRM_XYZ_fixed FOXIT_png_get_cHRM_XYZ_fixed 543 #define png_set_cHRM FOXIT_png_set_cHRM 544 #define png_set_cHRM_XYZ FOXIT_png_set_cHRM_XYZ 545 #define png_set_cHRM_fixed FOXIT_png_set_cHRM_fixed 546 #define png_set_cHRM_XYZ_fixed FOXIT_png_set_cHRM_XYZ_fixed 547 #define png_get_gAMA FOXIT_png_get_gAMA 548 #define png_set_gAMA FOXIT_png_set_gAMA 549 #define png_set_gAMA_fixed FOXIT_png_set_gAMA_fixed 550 #define png_get_hIST FOXIT_png_get_hIST 551 #define png_set_hIST FOXIT_png_set_hIST 552 #define png_get_IHDR FOXIT_png_get_IHDR 553 #define png_set_IHDR FOXIT_png_set_IHDR 554 #define png_get_oFFs FOXIT_png_get_oFFs 555 #define png_set_oFFs FOXIT_png_set_oFFs 556 #define png_get_pCAL FOXIT_png_get_pCAL 557 #define png_set_pCAL FOXIT_png_set_pCAL 558 #define png_set_pHYs FOXIT_png_set_pHYs 559 #define png_get_PLTE FOXIT_png_get_PLTE 560 #define png_set_PLTE FOXIT_png_set_PLTE 561 #define png_get_sBIT FOXIT_png_get_sBIT 562 #define png_set_sBIT FOXIT_png_set_sBIT 563 #define png_get_sRGB FOXIT_png_get_sRGB 564 #define png_set_sRGB FOXIT_png_set_sRGB 565 #define png_set_sRGB_gAMA_and_cHRM FOXIT_png_set_sRGB_gAMA_and_cHRM 566 #define png_get_iCCP FOXIT_png_get_iCCP 567 #define png_set_iCCP FOXIT_png_set_iCCP 568 #define png_get_sPLT FOXIT_png_get_sPLT 569 #define png_set_sPLT FOXIT_png_set_sPLT 570 #define png_get_text FOXIT_png_get_text 571 #define png_set_text FOXIT_png_set_text 572 #define png_get_tIME FOXIT_png_get_tIME 573 #define png_set_tIME FOXIT_png_set_tIME 574 #define png_get_tRNS FOXIT_png_get_tRNS 575 #define png_set_tRNS FOXIT_png_set_tRNS 576 #define png_get_sCAL FOXIT_png_get_sCAL 577 #define png_get_sCAL_fixed FOXIT_png_get_sCAL_fixed 578 #define png_get_sCAL_s FOXIT_png_get_sCAL_s 579 #define png_set_sCAL FOXIT_png_set_sCAL 580 #define png_set_sCAL_s FOXIT_png_set_sCAL_s 581 #define png_set_keep_unknown_chunks FOXIT_png_set_keep_unknown_chunks 582 #define png_set_unknown_chunks FOXIT_png_set_unknown_chunks 583 #define png_set_unknown_chunk_location FOXIT_png_set_unknown_chunk_location 584 #define png_get_unknown_chunks FOXIT_png_get_unknown_chunks 585 #define png_set_invalid FOXIT_png_set_invalid 586 #define png_read_png FOXIT_png_read_png 587 #define png_write_png FOXIT_png_write_png 588 #define png_permit_mng_features FOXIT_png_permit_mng_features 589 #define png_set_strip_error_numbers FOXIT_png_set_strip_error_numbers 590 #define png_set_user_limits FOXIT_png_set_user_limits 591 #define png_get_user_width_max FOXIT_png_get_user_width_max 592 #define png_get_user_height_max FOXIT_png_get_user_height_max 593 #define png_set_chunk_cache_max FOXIT_png_set_chunk_cache_max 594 #define png_get_chunk_cache_max FOXIT_png_get_chunk_cache_max 595 #define png_set_chunk_malloc_max FOXIT_png_set_chunk_malloc_max 596 #define png_get_chunk_malloc_max FOXIT_png_get_chunk_malloc_max 597 #define png_get_pixels_per_inch FOXIT_png_get_pixels_per_inch 598 #define png_get_x_pixels_per_inch FOXIT_png_get_x_pixels_per_inch 599 #define png_get_y_pixels_per_inch FOXIT_png_get_y_pixels_per_inch 600 #define png_get_x_offset_inches FOXIT_png_get_x_offset_inches 601 #define png_get_x_offset_inches_fixed FOXIT_png_get_x_offset_inches_fixed 602 #define png_get_y_offset_inches FOXIT_png_get_y_offset_inches 603 #define png_get_y_offset_inches_fixed FOXIT_png_get_y_offset_inches_fixed 604 #define png_get_pHYs_dpi FOXIT_png_get_pHYs_dpi 605 #define png_get_io_state FOXIT_png_get_io_state 606 #define png_get_io_chunk_name FOXIT_png_get_io_chunk_name 607 #define png_get_io_chunk_type FOXIT_png_get_io_chunk_type 608 #define png_get_uint_31 FOXIT_png_get_uint_31 609 #define png_get_uint_32 FOXIT_png_get_uint_32 610 #define png_get_uint_16 FOXIT_png_get_uint_16 611 #define png_get_int_32 FOXIT_png_get_int_32 612 #define png_save_uint_32 FOXIT_png_save_uint_32 613 #define png_save_int_32 FOXIT_png_save_int_32 614 #define png_save_uint_16 FOXIT_png_save_uint_16 615 #define png_image_begin_read_from_file FOXIT_png_image_begin_read_from_file 616 #define png_image_begin_read_from_stdio FOXIT_png_image_begin_read_from_stdio 617 #define png_image_begin_read_from_memory FOXIT_png_image_begin_read_from_memory 618 #define png_image_finish_read FOXIT_png_image_finish_read 619 #define png_image_free FOXIT_png_image_free 620 #define png_image_write_to_file FOXIT_png_image_write_to_file 621 #define png_image_write_to_stdio FOXIT_png_image_write_to_stdio 622 #define png_set_check_for_invalid_index FOXIT_png_set_check_for_invalid_index 623 #define png_get_palette_max FOXIT_png_get_palette_max 624 #define png_set_option FOXIT_png_set_option 625 626 #define png_set_strip_16 FOXIT_png_set_strip_16 627 #define png_64bit_product FOXIT_png_64bit_product 628 #define png_check_cHRM_fixed FOXIT_png_check_cHRM_fixed 629 #define png_free FOXIT_png_free 630 #define png_free_default FOXIT_png_free_default 631 #define png_get_mem_ptr FOXIT_png_get_mem_ptr 632 #define png_malloc FOXIT_png_malloc 633 #define png_malloc_default FOXIT_png_malloc_default 634 #define png_malloc_warn FOXIT_png_malloc_warn 635 #define png_memcpy_check FOXIT_png_memcpy_check 636 #define png_memset_check FOXIT_png_memset_check 637 #define png_pass_dsp_mask FOXIT_png_pass_dsp_mask 638 #define png_pass_inc FOXIT_png_pass_inc 639 #define png_pass_mask FOXIT_png_pass_mask 640 #define png_pass_start FOXIT_png_pass_start 641 #define png_pass_yinc FOXIT_png_pass_yinc 642 #define png_pass_ystart FOXIT_png_pass_ystart 643 #define png_set_mem_fn FOXIT_png_set_mem_fn 644 645 /* Version information for png.h - this should match the version in png.c */ 646 #define PNG_LIBPNG_VER_STRING "1.6.3" 647 #define PNG_HEADER_VERSION_STRING \ 648 " libpng version 1.6.3 - July 18, 2013\n" 649 650 #define PNG_LIBPNG_VER_SONUM 16 651 #define PNG_LIBPNG_VER_DLLNUM 16 652 653 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */ 654 #define PNG_LIBPNG_VER_MAJOR 1 655 #define PNG_LIBPNG_VER_MINOR 6 656 #define PNG_LIBPNG_VER_RELEASE 3 657 658 /* This should match the numeric part of the final component of 659 * PNG_LIBPNG_VER_STRING, omitting any leading zero: 660 */ 661 662 #define PNG_LIBPNG_VER_BUILD 0 663 664 /* Release Status */ 665 #define PNG_LIBPNG_BUILD_ALPHA 1 666 #define PNG_LIBPNG_BUILD_BETA 2 667 #define PNG_LIBPNG_BUILD_RC 3 668 #define PNG_LIBPNG_BUILD_STABLE 4 669 #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 670 671 /* Release-Specific Flags */ 672 #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with 673 PNG_LIBPNG_BUILD_STABLE only */ 674 #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with 675 PNG_LIBPNG_BUILD_SPECIAL */ 676 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with 677 PNG_LIBPNG_BUILD_PRIVATE */ 678 679 #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE 680 681 /* Careful here. At one time, Guy wanted to use 082, but that would be octal. 682 * We must not include leading zeros. 683 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only 684 * version 1.0.0 was mis-numbered 100 instead of 10000). From 685 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release 686 */ 687 #define PNG_LIBPNG_VER 10603 /* 1.6.3 */ 688 689 /* Library configuration: these options cannot be changed after 690 * the library has been built. 691 */ 692 #ifndef PNGLCONF_H 693 /* If pnglibconf.h is missing, you can 694 * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h 695 */ 696 # include "pnglibconf.h" 697 #endif 698 699 #ifndef PNG_VERSION_INFO_ONLY 700 /* Machine specific configuration. */ 701 # include "pngconf.h" 702 #endif 703 704 /* 705 * Added at libpng-1.2.8 706 * 707 * Ref MSDN: Private as priority over Special 708 * VS_FF_PRIVATEBUILD File *was not* built using standard release 709 * procedures. If this value is given, the StringFileInfo block must 710 * contain a PrivateBuild string. 711 * 712 * VS_FF_SPECIALBUILD File *was* built by the original company using 713 * standard release procedures but is a variation of the standard 714 * file of the same version number. If this value is given, the 715 * StringFileInfo block must contain a SpecialBuild string. 716 */ 717 718 #ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */ 719 # define PNG_LIBPNG_BUILD_TYPE \ 720 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) 721 #else 722 # ifdef PNG_LIBPNG_SPECIALBUILD 723 # define PNG_LIBPNG_BUILD_TYPE \ 724 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) 725 # else 726 # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) 727 # endif 728 #endif 729 730 #ifndef PNG_VERSION_INFO_ONLY 731 732 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */ 733 #ifdef __cplusplus 734 extern "C" { 735 #endif /* __cplusplus */ 736 737 /* Version information for C files, stored in png.c. This had better match 738 * the version above. 739 */ 740 #define png_libpng_ver png_get_header_ver(NULL) 741 742 /* This file is arranged in several sections: 743 * 744 * 1. Any configuration options that can be specified by for the application 745 * code when it is built. (Build time configuration is in pnglibconf.h) 746 * 2. Type definitions (base types are defined in pngconf.h), structure 747 * definitions. 748 * 3. Exported library functions. 749 * 4. Simplified API. 750 * 751 * The library source code has additional files (principally pngpriv.h) that 752 * allow configuration of the library. 753 */ 754 /* Section 1: run time configuration 755 * See pnglibconf.h for build time configuration 756 * 757 * Run time configuration allows the application to choose between 758 * implementations of certain arithmetic APIs. The default is set 759 * at build time and recorded in pnglibconf.h, but it is safe to 760 * override these (and only these) settings. Note that this won't 761 * change what the library does, only application code, and the 762 * settings can (and probably should) be made on a per-file basis 763 * by setting the #defines before including png.h 764 * 765 * Use macros to read integers from PNG data or use the exported 766 * functions? 767 * PNG_USE_READ_MACROS: use the macros (see below) Note that 768 * the macros evaluate their argument multiple times. 769 * PNG_NO_USE_READ_MACROS: call the relevant library function. 770 * 771 * Use the alternative algorithm for compositing alpha samples that 772 * does not use division? 773 * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' 774 * algorithm. 775 * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. 776 * 777 * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is 778 * false? 779 * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error 780 * APIs to png_warning. 781 * Otherwise the calls are mapped to png_error. 782 */ 783 784 /* Section 2: type definitions, including structures and compile time 785 * constants. 786 * See pngconf.h for base types that vary by machine/system 787 */ 788 789 /* This triggers a compiler error in png.c, if png.c and png.h 790 * do not agree upon the version number. 791 */ 792 typedef char* png_libpng_version_1_6_3; 793 794 /* Basic control structions. Read libpng-manual.txt or libpng.3 for more info. 795 * 796 * png_struct is the cache of information used while reading or writing a single 797 * PNG file. One of these is always required, although the simplified API 798 * (below) hides the creation and destruction of it. 799 */ 800 typedef struct png_struct_def png_struct; 801 typedef const png_struct * png_const_structp; 802 typedef png_struct * png_structp; 803 typedef png_struct * * png_structpp; 804 805 /* png_info contains information read from or to be written to a PNG file. One 806 * or more of these must exist while reading or creating a PNG file. The 807 * information is not used by libpng during read but is used to control what 808 * gets written when a PNG file is created. "png_get_" function calls read 809 * information during read and "png_set_" functions calls write information 810 * when creating a PNG. 811 * been moved into a separate header file that is not accessible to 812 * applications. Read libpng-manual.txt or libpng.3 for more info. 813 */ 814 typedef struct png_info_def png_info; 815 typedef png_info * png_infop; 816 typedef const png_info * png_const_infop; 817 typedef png_info * * png_infopp; 818 819 /* Types with names ending 'p' are pointer types. The corresponding types with 820 * names ending 'rp' are identical pointer types except that the pointer is 821 * marked 'restrict', which means that it is the only pointer to the object 822 * passed to the function. Applications should not use the 'restrict' types; 823 * it is always valid to pass 'p' to a pointer with a function argument of the 824 * corresponding 'rp' type. Different compilers have different rules with 825 * regard to type matching in the presence of 'restrict'. For backward 826 * compatibility libpng callbacks never have 'restrict' in their parameters and, 827 * consequentially, writing portable application code is extremely difficult if 828 * an attempt is made to use 'restrict'. 829 */ 830 typedef png_struct * PNG_RESTRICT png_structrp; 831 typedef const png_struct * PNG_RESTRICT png_const_structrp; 832 typedef png_info * PNG_RESTRICT png_inforp; 833 typedef const png_info * PNG_RESTRICT png_const_inforp; 834 835 /* Three color definitions. The order of the red, green, and blue, (and the 836 * exact size) is not important, although the size of the fields need to 837 * be png_byte or png_uint_16 (as defined below). 838 */ 839 typedef struct png_color_struct 840 { 841 png_byte red; 842 png_byte green; 843 png_byte blue; 844 } png_color; 845 typedef png_color * png_colorp; 846 typedef const png_color * png_const_colorp; 847 typedef png_color * * png_colorpp; 848 849 typedef struct png_color_16_struct 850 { 851 png_byte index; /* used for palette files */ 852 png_uint_16 red; /* for use in red green blue files */ 853 png_uint_16 green; 854 png_uint_16 blue; 855 png_uint_16 gray; /* for use in grayscale files */ 856 } png_color_16; 857 typedef png_color_16 * png_color_16p; 858 typedef const png_color_16 * png_const_color_16p; 859 typedef png_color_16 * * png_color_16pp; 860 861 typedef struct png_color_8_struct 862 { 863 png_byte red; /* for use in red green blue files */ 864 png_byte green; 865 png_byte blue; 866 png_byte gray; /* for use in grayscale files */ 867 png_byte alpha; /* for alpha channel files */ 868 } png_color_8; 869 typedef png_color_8 * png_color_8p; 870 typedef const png_color_8 * png_const_color_8p; 871 typedef png_color_8 * * png_color_8pp; 872 873 /* 874 * The following two structures are used for the in-core representation 875 * of sPLT chunks. 876 */ 877 typedef struct png_sPLT_entry_struct 878 { 879 png_uint_16 red; 880 png_uint_16 green; 881 png_uint_16 blue; 882 png_uint_16 alpha; 883 png_uint_16 frequency; 884 } png_sPLT_entry; 885 typedef png_sPLT_entry * png_sPLT_entryp; 886 typedef const png_sPLT_entry * png_const_sPLT_entryp; 887 typedef png_sPLT_entry * * png_sPLT_entrypp; 888 889 /* When the depth of the sPLT palette is 8 bits, the color and alpha samples 890 * occupy the LSB of their respective members, and the MSB of each member 891 * is zero-filled. The frequency member always occupies the full 16 bits. 892 */ 893 894 typedef struct png_sPLT_struct 895 { 896 png_charp name; /* palette name */ 897 png_byte depth; /* depth of palette samples */ 898 png_sPLT_entryp entries; /* palette entries */ 899 png_int_32 nentries; /* number of palette entries */ 900 } png_sPLT_t; 901 typedef png_sPLT_t * png_sPLT_tp; 902 typedef const png_sPLT_t * png_const_sPLT_tp; 903 typedef png_sPLT_t * * png_sPLT_tpp; 904 905 #ifdef PNG_TEXT_SUPPORTED 906 /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, 907 * and whether that contents is compressed or not. The "key" field 908 * points to a regular zero-terminated C string. The "text" fields can be a 909 * regular C string, an empty string, or a NULL pointer. 910 * However, the structure returned by png_get_text() will always contain 911 * the "text" field as a regular zero-terminated C string (possibly 912 * empty), never a NULL pointer, so it can be safely used in printf() and 913 * other string-handling functions. Note that the "itxt_length", "lang", and 914 * "lang_key" members of the structure only exist when the library is built 915 * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by 916 * default without iTXt support. Also note that when iTXt *is* supported, 917 * the "lang" and "lang_key" fields contain NULL pointers when the 918 * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or 919 * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the 920 * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag" 921 * which is always 0 or 1, or its "compression method" which is always 0. 922 */ 923 typedef struct png_text_struct 924 { 925 int compression; /* compression value: 926 -1: tEXt, none 927 0: zTXt, deflate 928 1: iTXt, none 929 2: iTXt, deflate */ 930 png_charp key; /* keyword, 1-79 character description of "text" */ 931 png_charp text; /* comment, may be an empty string (ie "") 932 or a NULL pointer */ 933 png_size_t text_length; /* length of the text string */ 934 png_size_t itxt_length; /* length of the itxt string */ 935 png_charp lang; /* language code, 0-79 characters 936 or a NULL pointer */ 937 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more 938 chars or a NULL pointer */ 939 } png_text; 940 typedef png_text * png_textp; 941 typedef const png_text * png_const_textp; 942 typedef png_text * * png_textpp; 943 #endif 944 945 /* Supported compression types for text in PNG files (tEXt, and zTXt). 946 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ 947 #define PNG_TEXT_COMPRESSION_NONE_WR -3 948 #define PNG_TEXT_COMPRESSION_zTXt_WR -2 949 #define PNG_TEXT_COMPRESSION_NONE -1 950 #define PNG_TEXT_COMPRESSION_zTXt 0 951 #define PNG_ITXT_COMPRESSION_NONE 1 952 #define PNG_ITXT_COMPRESSION_zTXt 2 953 #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ 954 955 /* png_time is a way to hold the time in an machine independent way. 956 * Two conversions are provided, both from time_t and struct tm. There 957 * is no portable way to convert to either of these structures, as far 958 * as I know. If you know of a portable way, send it to me. As a side 959 * note - PNG has always been Year 2000 compliant! 960 */ 961 typedef struct png_time_struct 962 { 963 png_uint_16 year; /* full year, as in, 1995 */ 964 png_byte month; /* month of year, 1 - 12 */ 965 png_byte day; /* day of month, 1 - 31 */ 966 png_byte hour; /* hour of day, 0 - 23 */ 967 png_byte minute; /* minute of hour, 0 - 59 */ 968 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ 969 } png_time; 970 typedef png_time * png_timep; 971 typedef const png_time * png_const_timep; 972 typedef png_time * * png_timepp; 973 974 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED 975 /* png_unknown_chunk is a structure to hold queued chunks for which there is 976 * no specific support. The idea is that we can use this to queue 977 * up private chunks for output even though the library doesn't actually 978 * know about their semantics. 979 * 980 * The data in the structure is set by libpng on read and used on write. 981 */ 982 typedef struct png_unknown_chunk_t 983 { 984 png_byte name[5]; /* Textual chunk name with '\0' terminator */ 985 png_byte *data; /* Data, should not be modified on read! */ 986 png_size_t size; 987 988 /* On write 'location' must be set using the flag values listed below. 989 * Notice that on read it is set by libpng however the values stored have 990 * more bits set than are listed below. Always treat the value as a 991 * bitmask. On write set only one bit - setting multiple bits may cause the 992 * chunk to be written in multiple places. 993 */ 994 png_byte location; /* mode of operation at read time */ 995 } 996 png_unknown_chunk; 997 998 typedef png_unknown_chunk * png_unknown_chunkp; 999 typedef const png_unknown_chunk * png_const_unknown_chunkp; 1000 typedef png_unknown_chunk * * png_unknown_chunkpp; 1001 #endif 1002 1003 /* Flag values for the unknown chunk location byte. */ 1004 #define PNG_HAVE_IHDR 0x01 1005 #define PNG_HAVE_PLTE 0x02 1006 #define PNG_AFTER_IDAT 0x08 1007 1008 /* Maximum positive integer used in PNG is (2^31)-1 */ 1009 #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) 1010 #define PNG_UINT_32_MAX ((png_uint_32)(-1)) 1011 #define PNG_SIZE_MAX ((png_size_t)(-1)) 1012 1013 /* These are constants for fixed point values encoded in the 1014 * PNG specification manner (x100000) 1015 */ 1016 #define PNG_FP_1 100000 1017 #define PNG_FP_HALF 50000 1018 #define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) 1019 #define PNG_FP_MIN (-PNG_FP_MAX) 1020 1021 /* These describe the color_type field in png_info. */ 1022 /* color type masks */ 1023 #define PNG_COLOR_MASK_PALETTE 1 1024 #define PNG_COLOR_MASK_COLOR 2 1025 #define PNG_COLOR_MASK_ALPHA 4 1026 1027 /* color types. Note that not all combinations are legal */ 1028 #define PNG_COLOR_TYPE_GRAY 0 1029 #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) 1030 #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) 1031 #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) 1032 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) 1033 /* aliases */ 1034 #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA 1035 #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA 1036 1037 /* This is for compression type. PNG 1.0-1.2 only define the single type. */ 1038 #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ 1039 #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE 1040 1041 /* This is for filter type. PNG 1.0-1.2 only define the single type. */ 1042 #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ 1043 #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ 1044 #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE 1045 1046 /* These are for the interlacing type. These values should NOT be changed. */ 1047 #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ 1048 #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ 1049 #define PNG_INTERLACE_LAST 2 /* Not a valid value */ 1050 1051 /* These are for the oFFs chunk. These values should NOT be changed. */ 1052 #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ 1053 #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ 1054 #define PNG_OFFSET_LAST 2 /* Not a valid value */ 1055 1056 /* These are for the pCAL chunk. These values should NOT be changed. */ 1057 #define PNG_EQUATION_LINEAR 0 /* Linear transformation */ 1058 #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ 1059 #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ 1060 #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ 1061 #define PNG_EQUATION_LAST 4 /* Not a valid value */ 1062 1063 /* These are for the sCAL chunk. These values should NOT be changed. */ 1064 #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ 1065 #define PNG_SCALE_METER 1 /* meters per pixel */ 1066 #define PNG_SCALE_RADIAN 2 /* radians per pixel */ 1067 #define PNG_SCALE_LAST 3 /* Not a valid value */ 1068 1069 /* These are for the pHYs chunk. These values should NOT be changed. */ 1070 #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ 1071 #define PNG_RESOLUTION_METER 1 /* pixels/meter */ 1072 #define PNG_RESOLUTION_LAST 2 /* Not a valid value */ 1073 1074 /* These are for the sRGB chunk. These values should NOT be changed. */ 1075 #define PNG_sRGB_INTENT_PERCEPTUAL 0 1076 #define PNG_sRGB_INTENT_RELATIVE 1 1077 #define PNG_sRGB_INTENT_SATURATION 2 1078 #define PNG_sRGB_INTENT_ABSOLUTE 3 1079 #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ 1080 1081 /* This is for text chunks */ 1082 #define PNG_KEYWORD_MAX_LENGTH 79 1083 1084 /* Maximum number of entries in PLTE/sPLT/tRNS arrays */ 1085 #define PNG_MAX_PALETTE_LENGTH 256 1086 1087 /* These determine if an ancillary chunk's data has been successfully read 1088 * from the PNG header, or if the application has filled in the corresponding 1089 * data in the info_struct to be written into the output file. The values 1090 * of the PNG_INFO_<chunk> defines should NOT be changed. 1091 */ 1092 #define PNG_INFO_gAMA 0x0001 1093 #define PNG_INFO_sBIT 0x0002 1094 #define PNG_INFO_cHRM 0x0004 1095 #define PNG_INFO_PLTE 0x0008 1096 #define PNG_INFO_tRNS 0x0010 1097 #define PNG_INFO_bKGD 0x0020 1098 #define PNG_INFO_hIST 0x0040 1099 #define PNG_INFO_pHYs 0x0080 1100 #define PNG_INFO_oFFs 0x0100 1101 #define PNG_INFO_tIME 0x0200 1102 #define PNG_INFO_pCAL 0x0400 1103 #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */ 1104 #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */ 1105 #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */ 1106 #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */ 1107 #define PNG_INFO_IDAT 0x8000 /* ESR, 1.0.6 */ 1108 1109 /* This is used for the transformation routines, as some of them 1110 * change these values for the row. It also should enable using 1111 * the routines for other purposes. 1112 */ 1113 typedef struct png_row_info_struct 1114 { 1115 png_uint_32 width; /* width of row */ 1116 png_size_t rowbytes; /* number of bytes in row */ 1117 png_byte color_type; /* color type of row */ 1118 png_byte bit_depth; /* bit depth of row */ 1119 png_byte channels; /* number of channels (1, 2, 3, or 4) */ 1120 png_byte pixel_depth; /* bits per pixel (depth * channels) */ 1121 } png_row_info; 1122 1123 typedef png_row_info * png_row_infop; 1124 typedef png_row_info * * png_row_infopp; 1125 1126 /* These are the function types for the I/O functions and for the functions 1127 * that allow the user to override the default I/O functions with his or her 1128 * own. The png_error_ptr type should match that of user-supplied warning 1129 * and error functions, while the png_rw_ptr type should match that of the 1130 * user read/write data functions. Note that the 'write' function must not 1131 * modify the buffer it is passed. The 'read' function, on the other hand, is 1132 * expected to return the read data in the buffer. 1133 */ 1134 typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); 1135 typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t)); 1136 typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); 1137 typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, 1138 int)); 1139 typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, 1140 int)); 1141 1142 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED 1143 typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); 1144 typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); 1145 1146 /* The following callback receives png_uint_32 row_number, int pass for the 1147 * png_bytep data of the row. When transforming an interlaced image the 1148 * row number is the row number within the sub-image of the interlace pass, so 1149 * the value will increase to the height of the sub-image (not the full image) 1150 * then reset to 0 for the next pass. 1151 * 1152 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to 1153 * find the output pixel (x,y) given an interlaced sub-image pixel 1154 * (row,col,pass). (See below for these macros.) 1155 */ 1156 typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, 1157 png_uint_32, int)); 1158 #endif 1159 1160 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ 1161 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) 1162 typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, 1163 png_bytep)); 1164 #endif 1165 1166 #ifdef PNG_USER_CHUNKS_SUPPORTED 1167 typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, 1168 png_unknown_chunkp)); 1169 #endif 1170 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED 1171 /* not used anywhere */ 1172 /* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); */ 1173 #endif 1174 1175 #ifdef PNG_SETJMP_SUPPORTED 1176 /* This must match the function definition in <setjmp.h>, and the application 1177 * must include this before png.h to obtain the definition of jmp_buf. The 1178 * function is required to be PNG_NORETURN, but this is not checked. If the 1179 * function does return the application will crash via an abort() or similar 1180 * system level call. 1181 * 1182 * If you get a warning here while building the library you may need to make 1183 * changes to ensure that pnglibconf.h records the calling convention used by 1184 * your compiler. This may be very difficult - try using a different compiler 1185 * to build the library! 1186 */ 1187 PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); 1188 #endif 1189 1190 /* Transform masks for the high-level interface */ 1191 #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ 1192 #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ 1193 #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ 1194 #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ 1195 #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ 1196 #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ 1197 #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ 1198 #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ 1199 #define PNG_TRANSFORM_BGR 0x0080 /* read and write */ 1200 #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ 1201 #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ 1202 #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ 1203 #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ 1204 /* Added to libpng-1.2.34 */ 1205 #define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER 1206 #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ 1207 /* Added to libpng-1.4.0 */ 1208 #define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ 1209 /* Added to libpng-1.5.4 */ 1210 #define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ 1211 #define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ 1212 1213 /* Flags for MNG supported features */ 1214 #define PNG_FLAG_MNG_EMPTY_PLTE 0x01 1215 #define PNG_FLAG_MNG_FILTER_64 0x04 1216 #define PNG_ALL_MNG_FEATURES 0x05 1217 1218 /* NOTE: prior to 1.5 these functions had no 'API' style declaration, 1219 * this allowed the zlib default functions to be used on Windows 1220 * platforms. In 1.5 the zlib default malloc (which just calls malloc and 1221 * ignores the first argument) should be completely compatible with the 1222 * following. 1223 */ 1224 typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, 1225 png_alloc_size_t)); 1226 typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); 1227 1228 /* Section 3: exported functions 1229 * Here are the function definitions most commonly used. This is not 1230 * the place to find out how to use libpng. See libpng-manual.txt for the 1231 * full explanation, see example.c for the summary. This just provides 1232 * a simple one line description of the use of each function. 1233 * 1234 * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in 1235 * pngconf.h and in the *.dfn files in the scripts directory. 1236 * 1237 * PNG_EXPORT(ordinal, type, name, (args)); 1238 * 1239 * ordinal: ordinal that is used while building 1240 * *.def files. The ordinal value is only 1241 * relevant when preprocessing png.h with 1242 * the *.dfn files for building symbol table 1243 * entries, and are removed by pngconf.h. 1244 * type: return type of the function 1245 * name: function name 1246 * args: function arguments, with types 1247 * 1248 * When we wish to append attributes to a function prototype we use 1249 * the PNG_EXPORTA() macro instead. 1250 * 1251 * PNG_EXPORTA(ordinal, type, name, (args), attributes); 1252 * 1253 * ordinal, type, name, and args: same as in PNG_EXPORT(). 1254 * attributes: function attributes 1255 */ 1256 1257 /* Returns the version number of the library */ 1258 PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); 1259 1260 /* Tell lib we have already handled the first <num_bytes> magic bytes. 1261 * Handling more than 8 bytes from the beginning of the file is an error. 1262 */ 1263 PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes)); 1264 1265 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a 1266 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG 1267 * signature, and non-zero otherwise. Having num_to_check == 0 or 1268 * start > 7 will always fail (ie return non-zero). 1269 */ 1270 PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start, 1271 png_size_t num_to_check)); 1272 1273 /* Simple signature checking function. This is the same as calling 1274 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). 1275 */ 1276 #define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) 1277 1278 /* Allocate and initialize png_ptr struct for reading, and any other memory. */ 1279 PNG_EXPORTA(4, png_structp, png_create_read_struct, 1280 (png_const_charp user_png_ver, png_voidp error_ptr, 1281 png_error_ptr error_fn, png_error_ptr warn_fn), 1282 PNG_ALLOCATED); 1283 1284 /* Allocate and initialize png_ptr struct for writing, and any other memory */ 1285 PNG_EXPORTA(5, png_structp, png_create_write_struct, 1286 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1287 png_error_ptr warn_fn), 1288 PNG_ALLOCATED); 1289 1290 PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size, 1291 (png_const_structrp png_ptr)); 1292 1293 PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr, 1294 png_size_t size)); 1295 1296 /* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp 1297 * match up. 1298 */ 1299 #ifdef PNG_SETJMP_SUPPORTED 1300 /* This function returns the jmp_buf built in to *png_ptr. It must be 1301 * supplied with an appropriate 'longjmp' function to use on that jmp_buf 1302 * unless the default error function is overridden in which case NULL is 1303 * acceptable. The size of the jmp_buf is checked against the actual size 1304 * allocated by the library - the call will return NULL on a mismatch 1305 * indicating an ABI mismatch. 1306 */ 1307 PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr, 1308 png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); 1309 # define png_jmpbuf(png_ptr) \ 1310 (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf)))) 1311 #else 1312 # define png_jmpbuf(png_ptr) \ 1313 (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) 1314 #endif 1315 /* This function should be used by libpng applications in place of 1316 * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it 1317 * will use it; otherwise it will call PNG_ABORT(). This function was 1318 * added in libpng-1.5.0. 1319 */ 1320 PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val), 1321 PNG_NORETURN); 1322 1323 #ifdef PNG_READ_SUPPORTED 1324 /* Reset the compression stream */ 1325 PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED); 1326 #endif 1327 1328 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ 1329 #ifdef PNG_USER_MEM_SUPPORTED 1330 PNG_EXPORTA(11, png_structp, png_create_read_struct_2, 1331 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1332 png_error_ptr warn_fn, 1333 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), 1334 PNG_ALLOCATED); 1335 PNG_EXPORTA(12, png_structp, png_create_write_struct_2, 1336 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1337 png_error_ptr warn_fn, 1338 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), 1339 PNG_ALLOCATED); 1340 #endif 1341 1342 /* Write the PNG file signature. */ 1343 PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr)); 1344 1345 /* Write a PNG chunk - size, type, (optional) data, CRC. */ 1346 PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep 1347 chunk_name, png_const_bytep data, png_size_t length)); 1348 1349 /* Write the start of a PNG chunk - length and chunk name. */ 1350 PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr, 1351 png_const_bytep chunk_name, png_uint_32 length)); 1352 1353 /* Write the data of a PNG chunk started with png_write_chunk_start(). */ 1354 PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr, 1355 png_const_bytep data, png_size_t length)); 1356 1357 /* Finish a chunk started with png_write_chunk_start() (includes CRC). */ 1358 PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr)); 1359 1360 /* Allocate and initialize the info structure */ 1361 PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr), 1362 PNG_ALLOCATED); 1363 1364 /* DEPRECATED: this function allowed init structures to be created using the 1365 * default allocation method (typically malloc). Use is deprecated in 1.6.0 and 1366 * the API will be removed in the future. 1367 */ 1368 PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr, 1369 png_size_t png_info_struct_size), PNG_DEPRECATED); 1370 1371 /* Writes all the PNG information before the image. */ 1372 PNG_EXPORT(20, void, png_write_info_before_PLTE, 1373 (png_structrp png_ptr, png_const_inforp info_ptr)); 1374 PNG_EXPORT(21, void, png_write_info, 1375 (png_structrp png_ptr, png_const_inforp info_ptr)); 1376 1377 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1378 /* Read the information before the actual image data. */ 1379 PNG_EXPORT(22, void, png_read_info, 1380 (png_structrp png_ptr, png_inforp info_ptr)); 1381 #endif 1382 1383 #ifdef PNG_TIME_RFC1123_SUPPORTED 1384 /* Convert to a US string format: there is no localization support in this 1385 * routine. The original implementation used a 29 character buffer in 1386 * png_struct, this will be removed in future versions. 1387 */ 1388 #if PNG_LIBPNG_VER < 10700 1389 /* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */ 1390 PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr, 1391 png_const_timep ptime),PNG_DEPRECATED); 1392 #endif 1393 PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29], 1394 png_const_timep ptime)); 1395 #endif 1396 1397 #ifdef PNG_CONVERT_tIME_SUPPORTED 1398 /* Convert from a struct tm to png_time */ 1399 PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, 1400 const struct tm * ttime)); 1401 1402 /* Convert from time_t to png_time. Uses gmtime() */ 1403 PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime)); 1404 #endif /* PNG_CONVERT_tIME_SUPPORTED */ 1405 1406 #ifdef PNG_READ_EXPAND_SUPPORTED 1407 /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ 1408 PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr)); 1409 PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr)); 1410 PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr)); 1411 PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr)); 1412 #endif 1413 1414 #ifdef PNG_READ_EXPAND_16_SUPPORTED 1415 /* Expand to 16-bit channels, forces conversion of palette to RGB and expansion 1416 * of a tRNS chunk if present. 1417 */ 1418 PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr)); 1419 #endif 1420 1421 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) 1422 /* Use blue, green, red order for pixels. */ 1423 PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr)); 1424 #endif 1425 1426 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED 1427 /* Expand the grayscale to 24-bit RGB if necessary. */ 1428 PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr)); 1429 #endif 1430 1431 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED 1432 /* Reduce RGB to grayscale. */ 1433 #define PNG_ERROR_ACTION_NONE 1 1434 #define PNG_ERROR_ACTION_WARN 2 1435 #define PNG_ERROR_ACTION_ERROR 3 1436 #define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ 1437 1438 PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr, 1439 int error_action, double red, double green)) 1440 PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr, 1441 int error_action, png_fixed_point red, png_fixed_point green)) 1442 1443 PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp 1444 png_ptr)); 1445 #endif 1446 1447 #ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED 1448 PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, 1449 png_colorp palette)); 1450 #endif 1451 1452 #ifdef PNG_READ_ALPHA_MODE_SUPPORTED 1453 /* How the alpha channel is interpreted - this affects how the color channels of 1454 * a PNG file are returned when an alpha channel, or tRNS chunk in a palette 1455 * file, is present. 1456 * 1457 * This has no effect on the way pixels are written into a PNG output 1458 * datastream. The color samples in a PNG datastream are never premultiplied 1459 * with the alpha samples. 1460 * 1461 * The default is to return data according to the PNG specification: the alpha 1462 * channel is a linear measure of the contribution of the pixel to the 1463 * corresponding composited pixel. The gamma encoded color channels must be 1464 * scaled according to the contribution and to do this it is necessary to undo 1465 * the encoding, scale the color values, perform the composition and reencode 1466 * the values. This is the 'PNG' mode. 1467 * 1468 * The alternative is to 'associate' the alpha with the color information by 1469 * storing color channel values that have been scaled by the alpha. The 1470 * advantage is that the color channels can be resampled (the image can be 1471 * scaled) in this form. The disadvantage is that normal practice is to store 1472 * linear, not (gamma) encoded, values and this requires 16-bit channels for 1473 * still images rather than the 8-bit channels that are just about sufficient if 1474 * gamma encoding is used. In addition all non-transparent pixel values, 1475 * including completely opaque ones, must be gamma encoded to produce the final 1476 * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the 1477 * latter being the two common names for associated alpha color channels.) 1478 * 1479 * Since it is not necessary to perform arithmetic on opaque color values so 1480 * long as they are not to be resampled and are in the final color space it is 1481 * possible to optimize the handling of alpha by storing the opaque pixels in 1482 * the PNG format (adjusted for the output color space) while storing partially 1483 * opaque pixels in the standard, linear, format. The accuracy required for 1484 * standard alpha composition is relatively low, because the pixels are 1485 * isolated, therefore typically the accuracy loss in storing 8-bit linear 1486 * values is acceptable. (This is not true if the alpha channel is used to 1487 * simulate transparency over large areas - use 16 bits or the PNG mode in 1488 * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is 1489 * treated as opaque only if the alpha value is equal to the maximum value. 1490 * 1491 * The final choice is to gamma encode the alpha channel as well. This is 1492 * broken because, in practice, no implementation that uses this choice 1493 * correctly undoes the encoding before handling alpha composition. Use this 1494 * choice only if other serious errors in the software or hardware you use 1495 * mandate it; the typical serious error is for dark halos to appear around 1496 * opaque areas of the composited PNG image because of arithmetic overflow. 1497 * 1498 * The API function png_set_alpha_mode specifies which of these choices to use 1499 * with an enumerated 'mode' value and the gamma of the required output: 1500 */ 1501 #define PNG_ALPHA_PNG 0 /* according to the PNG standard */ 1502 #define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ 1503 #define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ 1504 #define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ 1505 #define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ 1506 #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ 1507 1508 PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode, 1509 double output_gamma)) 1510 PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr, 1511 int mode, png_fixed_point output_gamma)) 1512 #endif 1513 1514 #if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) 1515 /* The output_gamma value is a screen gamma in libpng terminology: it expresses 1516 * how to decode the output values, not how they are encoded. The values used 1517 * correspond to the normal numbers used to describe the overall gamma of a 1518 * computer display system; for example 2.2 for an sRGB conformant system. The 1519 * values are scaled by 100000 in the _fixed version of the API (so 220000 for 1520 * sRGB.) 1521 * 1522 * The inverse of the value is always used to provide a default for the PNG file 1523 * encoding if it has no gAMA chunk and if png_set_gamma() has not been called 1524 * to override the PNG gamma information. 1525 * 1526 * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode 1527 * opaque pixels however pixels with lower alpha values are not encoded, 1528 * regardless of the output gamma setting. 1529 * 1530 * When the standard Porter Duff handling is requested with mode 1 the output 1531 * encoding is set to be linear and the output_gamma value is only relevant 1532 * as a default for input data that has no gamma information. The linear output 1533 * encoding will be overridden if png_set_gamma() is called - the results may be 1534 * highly unexpected! 1535 * 1536 * The following numbers are derived from the sRGB standard and the research 1537 * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of 1538 * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing 1539 * correction required to take account of any differences in the color 1540 * environment of the original scene and the intended display environment; the 1541 * value expresses how to *decode* the image for display, not how the original 1542 * data was *encoded*. 1543 * 1544 * sRGB provides a peg for the PNG standard by defining a viewing environment. 1545 * sRGB itself, and earlier TV standards, actually use a more complex transform 1546 * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is 1547 * limited to simple power laws.) By saying that an image for direct display on 1548 * an sRGB conformant system should be stored with a gAMA chunk value of 45455 1549 * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification 1550 * makes it possible to derive values for other display systems and 1551 * environments. 1552 * 1553 * The Mac value is deduced from the sRGB based on an assumption that the actual 1554 * extra viewing correction used in early Mac display systems was implemented as 1555 * a power 1.45 lookup table. 1556 * 1557 * Any system where a programmable lookup table is used or where the behavior of 1558 * the final display device characteristics can be changed requires system 1559 * specific code to obtain the current characteristic. However this can be 1560 * difficult and most PNG gamma correction only requires an approximate value. 1561 * 1562 * By default, if png_set_alpha_mode() is not called, libpng assumes that all 1563 * values are unencoded, linear, values and that the output device also has a 1564 * linear characteristic. This is only very rarely correct - it is invariably 1565 * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the 1566 * default if you don't know what the right answer is! 1567 * 1568 * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS 1569 * 10.6) which used a correction table to implement a somewhat lower gamma on an 1570 * otherwise sRGB system. 1571 * 1572 * Both these values are reserved (not simple gamma values) in order to allow 1573 * more precise correction internally in the future. 1574 * 1575 * NOTE: the following values can be passed to either the fixed or floating 1576 * point APIs, but the floating point API will also accept floating point 1577 * values. 1578 */ 1579 #define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ 1580 #define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ 1581 #define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ 1582 #define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ 1583 #endif 1584 1585 /* The following are examples of calls to png_set_alpha_mode to achieve the 1586 * required overall gamma correction and, where necessary, alpha 1587 * premultiplication. 1588 * 1589 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); 1590 * This is the default libpng handling of the alpha channel - it is not 1591 * pre-multiplied into the color components. In addition the call states 1592 * that the output is for a sRGB system and causes all PNG files without gAMA 1593 * chunks to be assumed to be encoded using sRGB. 1594 * 1595 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); 1596 * In this case the output is assumed to be something like an sRGB conformant 1597 * display preceeded by a power-law lookup table of power 1.45. This is how 1598 * early Mac systems behaved. 1599 * 1600 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); 1601 * This is the classic Jim Blinn approach and will work in academic 1602 * environments where everything is done by the book. It has the shortcoming 1603 * of assuming that input PNG data with no gamma information is linear - this 1604 * is unlikely to be correct unless the PNG files where generated locally. 1605 * Most of the time the output precision will be so low as to show 1606 * significant banding in dark areas of the image. 1607 * 1608 * png_set_expand_16(pp); 1609 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); 1610 * This is a somewhat more realistic Jim Blinn inspired approach. PNG files 1611 * are assumed to have the sRGB encoding if not marked with a gamma value and 1612 * the output is always 16 bits per component. This permits accurate scaling 1613 * and processing of the data. If you know that your input PNG files were 1614 * generated locally you might need to replace PNG_DEFAULT_sRGB with the 1615 * correct value for your system. 1616 * 1617 * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); 1618 * If you just need to composite the PNG image onto an existing background 1619 * and if you control the code that does this you can use the optimization 1620 * setting. In this case you just copy completely opaque pixels to the 1621 * output. For pixels that are not completely transparent (you just skip 1622 * those) you do the composition math using png_composite or png_composite_16 1623 * below then encode the resultant 8-bit or 16-bit values to match the output 1624 * encoding. 1625 * 1626 * Other cases 1627 * If neither the PNG nor the standard linear encoding work for you because 1628 * of the software or hardware you use then you have a big problem. The PNG 1629 * case will probably result in halos around the image. The linear encoding 1630 * will probably result in a washed out, too bright, image (it's actually too 1631 * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably 1632 * substantially reduce the halos. Alternatively try: 1633 * 1634 * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); 1635 * This option will also reduce the halos, but there will be slight dark 1636 * halos round the opaque parts of the image where the background is light. 1637 * In the OPTIMIZED mode the halos will be light halos where the background 1638 * is dark. Take your pick - the halos are unavoidable unless you can get 1639 * your hardware/software fixed! (The OPTIMIZED approach is slightly 1640 * faster.) 1641 * 1642 * When the default gamma of PNG files doesn't match the output gamma. 1643 * If you have PNG files with no gamma information png_set_alpha_mode allows 1644 * you to provide a default gamma, but it also sets the ouput gamma to the 1645 * matching value. If you know your PNG files have a gamma that doesn't 1646 * match the output you can take advantage of the fact that 1647 * png_set_alpha_mode always sets the output gamma but only sets the PNG 1648 * default if it is not already set: 1649 * 1650 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); 1651 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); 1652 * The first call sets both the default and the output gamma values, the 1653 * second call overrides the output gamma without changing the default. This 1654 * is easier than achieving the same effect with png_set_gamma. You must use 1655 * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will 1656 * fire if more than one call to png_set_alpha_mode and png_set_background is 1657 * made in the same read operation, however multiple calls with PNG_ALPHA_PNG 1658 * are ignored. 1659 */ 1660 1661 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED 1662 PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr)); 1663 #endif 1664 1665 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ 1666 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) 1667 PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr)); 1668 #endif 1669 1670 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ 1671 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) 1672 PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr)); 1673 #endif 1674 1675 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) 1676 /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */ 1677 PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler, 1678 int flags)); 1679 /* The values of the PNG_FILLER_ defines should NOT be changed */ 1680 # define PNG_FILLER_BEFORE 0 1681 # define PNG_FILLER_AFTER 1 1682 /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ 1683 PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr, 1684 png_uint_32 filler, int flags)); 1685 #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */ 1686 1687 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) 1688 /* Swap bytes in 16-bit depth files. */ 1689 PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr)); 1690 #endif 1691 1692 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) 1693 /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ 1694 PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr)); 1695 #endif 1696 1697 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ 1698 defined(PNG_WRITE_PACKSWAP_SUPPORTED) 1699 /* Swap packing order of pixels in bytes. */ 1700 PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr)); 1701 #endif 1702 1703 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) 1704 /* Converts files to legal bit depths. */ 1705 PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p 1706 true_bits)); 1707 #endif 1708 1709 #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ 1710 defined(PNG_WRITE_INTERLACING_SUPPORTED) 1711 /* Have the code handle the interlacing. Returns the number of passes. 1712 * MUST be called before png_read_update_info or png_start_read_image, 1713 * otherwise it will not have the desired effect. Note that it is still 1714 * necessary to call png_read_row or png_read_rows png_get_image_height 1715 * times for each pass. 1716 */ 1717 PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr)); 1718 #endif 1719 1720 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) 1721 /* Invert monochrome files */ 1722 PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr)); 1723 #endif 1724 1725 #ifdef PNG_READ_BACKGROUND_SUPPORTED 1726 /* Handle alpha and tRNS by replacing with a background color. Prior to 1727 * libpng-1.5.4 this API must not be called before the PNG file header has been 1728 * read. Doing so will result in unexpected behavior and possible warnings or 1729 * errors if the PNG file contains a bKGD chunk. 1730 */ 1731 PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr, 1732 png_const_color_16p background_color, int background_gamma_code, 1733 int need_expand, double background_gamma)) 1734 PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr, 1735 png_const_color_16p background_color, int background_gamma_code, 1736 int need_expand, png_fixed_point background_gamma)) 1737 #endif 1738 #ifdef PNG_READ_BACKGROUND_SUPPORTED 1739 # define PNG_BACKGROUND_GAMMA_UNKNOWN 0 1740 # define PNG_BACKGROUND_GAMMA_SCREEN 1 1741 # define PNG_BACKGROUND_GAMMA_FILE 2 1742 # define PNG_BACKGROUND_GAMMA_UNIQUE 3 1743 #endif 1744 1745 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED 1746 /* Scale a 16-bit depth file down to 8-bit, accurately. */ 1747 PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr)); 1748 #endif 1749 1750 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED 1751 #define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */ 1752 /* Strip the second byte of information from a 16-bit depth file. */ 1753 PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr)); 1754 #endif 1755 1756 #ifdef PNG_READ_QUANTIZE_SUPPORTED 1757 /* Turn on quantizing, and reduce the palette to the number of colors 1758 * available. 1759 */ 1760 PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr, 1761 png_colorp palette, int num_palette, int maximum_colors, 1762 png_const_uint_16p histogram, int full_quantize)); 1763 #endif 1764 1765 #ifdef PNG_READ_GAMMA_SUPPORTED 1766 /* The threshold on gamma processing is configurable but hard-wired into the 1767 * library. The following is the floating point variant. 1768 */ 1769 #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) 1770 1771 /* Handle gamma correction. Screen_gamma=(display_exponent). 1772 * NOTE: this API simply sets the screen and file gamma values. It will 1773 * therefore override the value for gamma in a PNG file if it is called after 1774 * the file header has been read - use with care - call before reading the PNG 1775 * file for best results! 1776 * 1777 * These routines accept the same gamma values as png_set_alpha_mode (described 1778 * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either 1779 * API (floating point or fixed.) Notice, however, that the 'file_gamma' value 1780 * is the inverse of a 'screen gamma' value. 1781 */ 1782 PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr, 1783 double screen_gamma, double override_file_gamma)) 1784 PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr, 1785 png_fixed_point screen_gamma, png_fixed_point override_file_gamma)) 1786 #endif 1787 1788 #ifdef PNG_WRITE_FLUSH_SUPPORTED 1789 /* Set how many lines between output flushes - 0 for no flushing */ 1790 PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows)); 1791 /* Flush the current PNG output buffer */ 1792 PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr)); 1793 #endif 1794 1795 /* Optional update palette with requested transformations */ 1796 PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr)); 1797 1798 /* Optional call to update the users info structure */ 1799 PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr, 1800 png_inforp info_ptr)); 1801 1802 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1803 /* Read one or more rows of image data. */ 1804 PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row, 1805 png_bytepp display_row, png_uint_32 num_rows)); 1806 #endif 1807 1808 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1809 /* Read a row of data. */ 1810 PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row, 1811 png_bytep display_row)); 1812 #endif 1813 1814 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1815 /* Read the whole image into memory at once. */ 1816 PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image)); 1817 #endif 1818 1819 /* Write a row of image data */ 1820 PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr, 1821 png_const_bytep row)); 1822 1823 /* Write a few rows of image data: (*row) is not written; however, the type 1824 * is declared as writeable to maintain compatibility with previous versions 1825 * of libpng and to allow the 'display_row' array from read_rows to be passed 1826 * unchanged to write_rows. 1827 */ 1828 PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row, 1829 png_uint_32 num_rows)); 1830 1831 /* Write the image data */ 1832 PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image)); 1833 1834 /* Write the end of the PNG file. */ 1835 PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr, 1836 png_inforp info_ptr)); 1837 1838 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1839 /* Read the end of the PNG file. */ 1840 PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr)); 1841 #endif 1842 1843 /* Free any memory associated with the png_info_struct */ 1844 PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr, 1845 png_infopp info_ptr_ptr)); 1846 1847 /* Free any memory associated with the png_struct and the png_info_structs */ 1848 PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, 1849 png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); 1850 1851 /* Free any memory associated with the png_struct and the png_info_structs */ 1852 PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, 1853 png_infopp info_ptr_ptr)); 1854 1855 /* Set the libpng method of handling chunk CRC errors */ 1856 PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action, 1857 int ancil_action)); 1858 1859 /* Values for png_set_crc_action() say how to handle CRC errors in 1860 * ancillary and critical chunks, and whether to use the data contained 1861 * therein. Note that it is impossible to "discard" data in a critical 1862 * chunk. For versions prior to 0.90, the action was always error/quit, 1863 * whereas in version 0.90 and later, the action for CRC errors in ancillary 1864 * chunks is warn/discard. These values should NOT be changed. 1865 * 1866 * value action:critical action:ancillary 1867 */ 1868 #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ 1869 #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ 1870 #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ 1871 #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ 1872 #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ 1873 #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ 1874 1875 /* These functions give the user control over the scan-line filtering in 1876 * libpng and the compression methods used by zlib. These functions are 1877 * mainly useful for testing, as the defaults should work with most users. 1878 * Those users who are tight on memory or want faster performance at the 1879 * expense of compression can modify them. See the compression library 1880 * header file (zlib.h) for an explination of the compression functions. 1881 */ 1882 1883 /* Set the filtering method(s) used by libpng. Currently, the only valid 1884 * value for "method" is 0. 1885 */ 1886 PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method, 1887 int filters)); 1888 1889 /* Flags for png_set_filter() to say which filters to use. The flags 1890 * are chosen so that they don't conflict with real filter types 1891 * below, in case they are supplied instead of the #defined constants. 1892 * These values should NOT be changed. 1893 */ 1894 #define PNG_NO_FILTERS 0x00 1895 #define PNG_FILTER_NONE 0x08 1896 #define PNG_FILTER_SUB 0x10 1897 #define PNG_FILTER_UP 0x20 1898 #define PNG_FILTER_AVG 0x40 1899 #define PNG_FILTER_PAETH 0x80 1900 #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \ 1901 PNG_FILTER_AVG | PNG_FILTER_PAETH) 1902 1903 /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. 1904 * These defines should NOT be changed. 1905 */ 1906 #define PNG_FILTER_VALUE_NONE 0 1907 #define PNG_FILTER_VALUE_SUB 1 1908 #define PNG_FILTER_VALUE_UP 2 1909 #define PNG_FILTER_VALUE_AVG 3 1910 #define PNG_FILTER_VALUE_PAETH 4 1911 #define PNG_FILTER_VALUE_LAST 5 1912 1913 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */ 1914 /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_ 1915 * defines, either the default (minimum-sum-of-absolute-differences), or 1916 * the experimental method (weighted-minimum-sum-of-absolute-differences). 1917 * 1918 * Weights are factors >= 1.0, indicating how important it is to keep the 1919 * filter type consistent between rows. Larger numbers mean the current 1920 * filter is that many times as likely to be the same as the "num_weights" 1921 * previous filters. This is cumulative for each previous row with a weight. 1922 * There needs to be "num_weights" values in "filter_weights", or it can be 1923 * NULL if the weights aren't being specified. Weights have no influence on 1924 * the selection of the first row filter. Well chosen weights can (in theory) 1925 * improve the compression for a given image. 1926 * 1927 * Costs are factors >= 1.0 indicating the relative decoding costs of a 1928 * filter type. Higher costs indicate more decoding expense, and are 1929 * therefore less likely to be selected over a filter with lower computational 1930 * costs. There needs to be a value in "filter_costs" for each valid filter 1931 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't 1932 * setting the costs. Costs try to improve the speed of decompression without 1933 * unduly increasing the compressed image size. 1934 * 1935 * A negative weight or cost indicates the default value is to be used, and 1936 * values in the range [0.0, 1.0) indicate the value is to remain unchanged. 1937 * The default values for both weights and costs are currently 1.0, but may 1938 * change if good general weighting/cost heuristics can be found. If both 1939 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method 1940 * to the UNWEIGHTED method, but with added encoding time/computation. 1941 */ 1942 PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr, 1943 int heuristic_method, int num_weights, png_const_doublep filter_weights, 1944 png_const_doublep filter_costs)) 1945 PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, 1946 (png_structrp png_ptr, int heuristic_method, int num_weights, 1947 png_const_fixed_point_p filter_weights, 1948 png_const_fixed_point_p filter_costs)) 1949 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ 1950 1951 /* Heuristic used for row filter selection. These defines should NOT be 1952 * changed. 1953 */ 1954 #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ 1955 #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ 1956 #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ 1957 #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ 1958 1959 #ifdef PNG_WRITE_SUPPORTED 1960 /* Set the library compression level. Currently, valid values range from 1961 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 1962 * (0 - no compression, 9 - "maximal" compression). Note that tests have 1963 * shown that zlib compression levels 3-6 usually perform as well as level 9 1964 * for PNG images, and do considerably fewer caclulations. In the future, 1965 * these values may not correspond directly to the zlib compression levels. 1966 */ 1967 PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr, 1968 int level)); 1969 1970 PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr, 1971 int mem_level)); 1972 1973 PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr, 1974 int strategy)); 1975 1976 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a 1977 * smaller value of window_bits if it can do so safely. 1978 */ 1979 PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr, 1980 int window_bits)); 1981 1982 PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr, 1983 int method)); 1984 #endif 1985 1986 #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED 1987 /* Also set zlib parameters for compressing non-IDAT chunks */ 1988 PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr, 1989 int level)); 1990 1991 PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr, 1992 int mem_level)); 1993 1994 PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr, 1995 int strategy)); 1996 1997 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a 1998 * smaller value of window_bits if it can do so safely. 1999 */ 2000 PNG_EXPORT(225, void, png_set_text_compression_window_bits, 2001 (png_structrp png_ptr, int window_bits)); 2002 2003 PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr, 2004 int method)); 2005 #endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */ 2006 2007 /* These next functions are called for input/output, memory, and error 2008 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, 2009 * and call standard C I/O routines such as fread(), fwrite(), and 2010 * fprintf(). These functions can be made to use other I/O routines 2011 * at run time for those applications that need to handle I/O in a 2012 * different manner by calling png_set_???_fn(). See libpng-manual.txt for 2013 * more information. 2014 */ 2015 2016 #ifdef PNG_STDIO_SUPPORTED 2017 /* Initialize the input/output for the PNG file to the default functions. */ 2018 PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp)); 2019 #endif 2020 2021 /* Replace the (error and abort), and warning functions with user 2022 * supplied functions. If no messages are to be printed you must still 2023 * write and use replacement functions. The replacement error_fn should 2024 * still do a longjmp to the last setjmp location if you are using this 2025 * method of error handling. If error_fn or warning_fn is NULL, the 2026 * default function will be used. 2027 */ 2028 2029 PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr, 2030 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); 2031 2032 /* Return the user pointer associated with the error functions */ 2033 PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr)); 2034 2035 /* Replace the default data output functions with a user supplied one(s). 2036 * If buffered output is not used, then output_flush_fn can be set to NULL. 2037 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time 2038 * output_flush_fn will be ignored (and thus can be NULL). 2039 * It is probably a mistake to use NULL for output_flush_fn if 2040 * write_data_fn is not also NULL unless you have built libpng with 2041 * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's 2042 * default flush function, which uses the standard *FILE structure, will 2043 * be used. 2044 */ 2045 PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr, 2046 png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); 2047 2048 /* Replace the default data input function with a user supplied one. */ 2049 PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr, 2050 png_rw_ptr read_data_fn)); 2051 2052 /* Return the user pointer associated with the I/O functions */ 2053 PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr)); 2054 2055 PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr, 2056 png_read_status_ptr read_row_fn)); 2057 2058 PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr, 2059 png_write_status_ptr write_row_fn)); 2060 2061 #ifdef PNG_USER_MEM_SUPPORTED 2062 /* Replace the default memory allocation functions with user supplied one(s). */ 2063 PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr, 2064 png_malloc_ptr malloc_fn, png_free_ptr free_fn)); 2065 /* Return the user pointer associated with the memory functions */ 2066 PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr)); 2067 #endif 2068 2069 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED 2070 PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr, 2071 png_user_transform_ptr read_user_transform_fn)); 2072 #endif 2073 2074 #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED 2075 PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr, 2076 png_user_transform_ptr write_user_transform_fn)); 2077 #endif 2078 2079 #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED 2080 PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr, 2081 png_voidp user_transform_ptr, int user_transform_depth, 2082 int user_transform_channels)); 2083 /* Return the user pointer associated with the user transform functions */ 2084 PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, 2085 (png_const_structrp png_ptr)); 2086 #endif 2087 2088 #ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED 2089 /* Return information about the row currently being processed. Note that these 2090 * APIs do not fail but will return unexpected results if called outside a user 2091 * transform callback. Also note that when transforming an interlaced image the 2092 * row number is the row number within the sub-image of the interlace pass, so 2093 * the value will increase to the height of the sub-image (not the full image) 2094 * then reset to 0 for the next pass. 2095 * 2096 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to 2097 * find the output pixel (x,y) given an interlaced sub-image pixel 2098 * (row,col,pass). (See below for these macros.) 2099 */ 2100 PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp)); 2101 PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp)); 2102 #endif 2103 2104 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED 2105 /* This callback is called only for *unknown* chunks. If 2106 * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known 2107 * chunks to be treated as unknown, however in this case the callback must do 2108 * any processing required by the chunk (e.g. by calling the appropriate 2109 * png_set_ APIs.) 2110 * 2111 * There is no write support - on write, by default, all the chunks in the 2112 * 'unknown' list are written in the specified position. 2113 * 2114 * The integer return from the callback function is interpreted thus: 2115 * 2116 * negative: An error occured, png_chunk_error will be called. 2117 * zero: The chunk was not handled, the chunk will be saved. A critical 2118 * chunk will cause an error at this point unless it is to be saved. 2119 * positive: The chunk was handled, libpng will ignore/discard it. 2120 * 2121 * See "INTERACTION WTIH USER CHUNK CALLBACKS" below for important notes about 2122 * how this behavior will change in libpng 1.7 2123 */ 2124 PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr, 2125 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); 2126 #endif 2127 2128 #ifdef PNG_USER_CHUNKS_SUPPORTED 2129 PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr)); 2130 #endif 2131 2132 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED 2133 /* Sets the function callbacks for the push reader, and a pointer to a 2134 * user-defined structure available to the callback functions. 2135 */ 2136 PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr, 2137 png_voidp progressive_ptr, png_progressive_info_ptr info_fn, 2138 png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); 2139 2140 /* Returns the user pointer associated with the push read functions */ 2141 PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, 2142 (png_const_structrp png_ptr)); 2143 2144 /* Function to be called when data becomes available */ 2145 PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr, 2146 png_inforp info_ptr, png_bytep buffer, png_size_t buffer_size)); 2147 2148 /* A function which may be called *only* within png_process_data to stop the 2149 * processing of any more data. The function returns the number of bytes 2150 * remaining, excluding any that libpng has cached internally. A subsequent 2151 * call to png_process_data must supply these bytes again. If the argument 2152 * 'save' is set to true the routine will first save all the pending data and 2153 * will always return 0. 2154 */ 2155 PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structrp, int save)); 2156 2157 /* A function which may be called *only* outside (after) a call to 2158 * png_process_data. It returns the number of bytes of data to skip in the 2159 * input. Normally it will return 0, but if it returns a non-zero value the 2160 * application must skip than number of bytes of input data and pass the 2161 * following data to the next call to png_process_data. 2162 */ 2163 PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp)); 2164 2165 #ifdef PNG_READ_INTERLACING_SUPPORTED 2166 /* Function that combines rows. 'new_row' is a flag that should come from 2167 * the callback and be non-NULL if anything needs to be done; the library 2168 * stores its own version of the new data internally and ignores the passed 2169 * in value. 2170 */ 2171 PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr, 2172 png_bytep old_row, png_const_bytep new_row)); 2173 #endif /* PNG_READ_INTERLACING_SUPPORTED */ 2174 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ 2175 2176 PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr, 2177 png_alloc_size_t size), PNG_ALLOCATED); 2178 /* Added at libpng version 1.4.0 */ 2179 PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr, 2180 png_alloc_size_t size), PNG_ALLOCATED); 2181 2182 /* Added at libpng version 1.2.4 */ 2183 PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr, 2184 png_alloc_size_t size), PNG_ALLOCATED); 2185 2186 /* Frees a pointer allocated by png_malloc() */ 2187 PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr)); 2188 2189 /* Free data that was allocated internally */ 2190 PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr, 2191 png_inforp info_ptr, png_uint_32 free_me, int num)); 2192 2193 /* Reassign responsibility for freeing existing data, whether allocated 2194 * by libpng or by the application; this works on the png_info structure passed 2195 * in, it does not change the state for other png_info structures. 2196 * 2197 * It is unlikely that this function works correctly as of 1.6.0 and using it 2198 * may result either in memory leaks or double free of allocated data. 2199 */ 2200 PNG_EXPORTA(99, void, png_data_freer, (png_const_structrp png_ptr, 2201 png_inforp info_ptr, int freer, png_uint_32 mask), PNG_DEPRECATED); 2202 2203 /* Assignments for png_data_freer */ 2204 #define PNG_DESTROY_WILL_FREE_DATA 1 2205 #define PNG_SET_WILL_FREE_DATA 1 2206 #define PNG_USER_WILL_FREE_DATA 2 2207 /* Flags for png_ptr->free_me and info_ptr->free_me */ 2208 #define PNG_FREE_HIST 0x0008 2209 #define PNG_FREE_ICCP 0x0010 2210 #define PNG_FREE_SPLT 0x0020 2211 #define PNG_FREE_ROWS 0x0040 2212 #define PNG_FREE_PCAL 0x0080 2213 #define PNG_FREE_SCAL 0x0100 2214 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED 2215 # define PNG_FREE_UNKN 0x0200 2216 #endif 2217 /* PNG_FREE_LIST 0x0400 removed in 1.6.0 because it is ignored */ 2218 #define PNG_FREE_PLTE 0x1000 2219 #define PNG_FREE_TRNS 0x2000 2220 #define PNG_FREE_TEXT 0x4000 2221 #define PNG_FREE_ALL 0x7fff 2222 #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ 2223 2224 #ifdef PNG_USER_MEM_SUPPORTED 2225 PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr, 2226 png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED); 2227 PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr, 2228 png_voidp ptr), PNG_DEPRECATED); 2229 #endif 2230 2231 #ifdef PNG_ERROR_TEXT_SUPPORTED 2232 /* Fatal error in PNG image of libpng - can't continue */ 2233 PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr, 2234 png_const_charp error_message), PNG_NORETURN); 2235 2236 /* The same, but the chunk name is prepended to the error string. */ 2237 PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr, 2238 png_const_charp error_message), PNG_NORETURN); 2239 2240 #else 2241 /* Fatal error in PNG image of libpng - can't continue */ 2242 PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN); 2243 #endif 2244 2245 #ifdef PNG_WARNINGS_SUPPORTED 2246 /* Non-fatal error in libpng. Can continue, but may have a problem. */ 2247 PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr, 2248 png_const_charp warning_message)); 2249 2250 /* Non-fatal error in libpng, chunk name is prepended to message. */ 2251 PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr, 2252 png_const_charp warning_message)); 2253 #endif 2254 2255 #ifdef PNG_BENIGN_ERRORS_SUPPORTED 2256 /* Benign error in libpng. Can continue, but may have a problem. 2257 * User can choose whether to handle as a fatal error or as a warning. */ 2258 PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr, 2259 png_const_charp warning_message)); 2260 2261 #ifdef PNG_READ_SUPPORTED 2262 /* Same, chunk name is prepended to message (only during read) */ 2263 PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr, 2264 png_const_charp warning_message)); 2265 #endif 2266 2267 PNG_EXPORT(109, void, png_set_benign_errors, 2268 (png_structrp png_ptr, int allowed)); 2269 #else 2270 # ifdef PNG_ALLOW_BENIGN_ERRORS 2271 # define png_benign_error png_warning 2272 # define png_chunk_benign_error png_chunk_warning 2273 # else 2274 # define png_benign_error png_error 2275 # define png_chunk_benign_error png_chunk_error 2276 # endif 2277 #endif 2278 2279 /* The png_set_<chunk> functions are for storing values in the png_info_struct. 2280 * Similarly, the png_get_<chunk> calls are used to read values from the 2281 * png_info_struct, either storing the parameters in the passed variables, or 2282 * setting pointers into the png_info_struct where the data is stored. The 2283 * png_get_<chunk> functions return a non-zero value if the data was available 2284 * in info_ptr, or return zero and do not change any of the parameters if the 2285 * data was not available. 2286 * 2287 * These functions should be used instead of directly accessing png_info 2288 * to avoid problems with future changes in the size and internal layout of 2289 * png_info_struct. 2290 */ 2291 /* Returns "flag" if chunk data is valid in info_ptr. */ 2292 PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr, 2293 png_const_inforp info_ptr, png_uint_32 flag)); 2294 2295 /* Returns number of bytes needed to hold a transformed row. */ 2296 PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structrp png_ptr, 2297 png_const_inforp info_ptr)); 2298 2299 #ifdef PNG_INFO_IMAGE_SUPPORTED 2300 /* Returns row_pointers, which is an array of pointers to scanlines that was 2301 * returned from png_read_png(). 2302 */ 2303 PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr, 2304 png_const_inforp info_ptr)); 2305 2306 /* Set row_pointers, which is an array of pointers to scanlines for use 2307 * by png_write_png(). 2308 */ 2309 PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr, 2310 png_inforp info_ptr, png_bytepp row_pointers)); 2311 #endif 2312 2313 /* Returns number of color channels in image. */ 2314 PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr, 2315 png_const_inforp info_ptr)); 2316 2317 #ifdef PNG_EASY_ACCESS_SUPPORTED 2318 /* Returns image width in pixels. */ 2319 PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr, 2320 png_const_inforp info_ptr)); 2321 2322 /* Returns image height in pixels. */ 2323 PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr, 2324 png_const_inforp info_ptr)); 2325 2326 /* Returns image bit_depth. */ 2327 PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr, 2328 png_const_inforp info_ptr)); 2329 2330 /* Returns image color_type. */ 2331 PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr, 2332 png_const_inforp info_ptr)); 2333 2334 /* Returns image filter_type. */ 2335 PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr, 2336 png_const_inforp info_ptr)); 2337 2338 /* Returns image interlace_type. */ 2339 PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr, 2340 png_const_inforp info_ptr)); 2341 2342 /* Returns image compression_type. */ 2343 PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr, 2344 png_const_inforp info_ptr)); 2345 2346 /* Returns image resolution in pixels per meter, from pHYs chunk data. */ 2347 PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, 2348 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2349 PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, 2350 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2351 PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, 2352 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2353 2354 /* Returns pixel aspect ratio, computed from pHYs chunk data. */ 2355 PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, 2356 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2357 PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, 2358 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2359 2360 /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ 2361 PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, 2362 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2363 PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, 2364 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2365 PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, 2366 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2367 PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, 2368 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2369 2370 #endif /* PNG_EASY_ACCESS_SUPPORTED */ 2371 2372 #ifdef PNG_READ_SUPPORTED 2373 /* Returns pointer to signature string read from PNG header */ 2374 PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr, 2375 png_const_inforp info_ptr)); 2376 #endif 2377 2378 #ifdef PNG_bKGD_SUPPORTED 2379 PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr, 2380 png_inforp info_ptr, png_color_16p *background)); 2381 #endif 2382 2383 #ifdef PNG_bKGD_SUPPORTED 2384 PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr, 2385 png_inforp info_ptr, png_const_color_16p background)); 2386 #endif 2387 2388 #ifdef PNG_cHRM_SUPPORTED 2389 PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr, 2390 png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x, 2391 double *red_y, double *green_x, double *green_y, double *blue_x, 2392 double *blue_y)) 2393 PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr, 2394 png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z, 2395 double *green_X, double *green_Y, double *green_Z, double *blue_X, 2396 double *blue_Y, double *blue_Z)) 2397 PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, 2398 (png_const_structrp png_ptr, png_const_inforp info_ptr, 2399 png_fixed_point *int_white_x, png_fixed_point *int_white_y, 2400 png_fixed_point *int_red_x, png_fixed_point *int_red_y, 2401 png_fixed_point *int_green_x, png_fixed_point *int_green_y, 2402 png_fixed_point *int_blue_x, png_fixed_point *int_blue_y)) 2403 PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, 2404 (png_const_structrp png_ptr, png_const_inforp info_ptr, 2405 png_fixed_point *int_red_X, png_fixed_point *int_red_Y, 2406 png_fixed_point *int_red_Z, png_fixed_point *int_green_X, 2407 png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, 2408 png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, 2409 png_fixed_point *int_blue_Z)) 2410 #endif 2411 2412 #ifdef PNG_cHRM_SUPPORTED 2413 PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr, 2414 png_inforp info_ptr, 2415 double white_x, double white_y, double red_x, double red_y, double green_x, 2416 double green_y, double blue_x, double blue_y)) 2417 PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr, 2418 png_inforp info_ptr, double red_X, double red_Y, double red_Z, 2419 double green_X, double green_Y, double green_Z, double blue_X, 2420 double blue_Y, double blue_Z)) 2421 PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr, 2422 png_inforp info_ptr, png_fixed_point int_white_x, 2423 png_fixed_point int_white_y, png_fixed_point int_red_x, 2424 png_fixed_point int_red_y, png_fixed_point int_green_x, 2425 png_fixed_point int_green_y, png_fixed_point int_blue_x, 2426 png_fixed_point int_blue_y)) 2427 PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr, 2428 png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, 2429 png_fixed_point int_red_Z, png_fixed_point int_green_X, 2430 png_fixed_point int_green_Y, png_fixed_point int_green_Z, 2431 png_fixed_point int_blue_X, png_fixed_point int_blue_Y, 2432 png_fixed_point int_blue_Z)) 2433 #endif 2434 2435 #ifdef PNG_gAMA_SUPPORTED 2436 PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr, 2437 png_const_inforp info_ptr, double *file_gamma)) 2438 PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, 2439 (png_const_structrp png_ptr, png_const_inforp info_ptr, 2440 png_fixed_point *int_file_gamma)) 2441 #endif 2442 2443 #ifdef PNG_gAMA_SUPPORTED 2444 PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr, 2445 png_inforp info_ptr, double file_gamma)) 2446 PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr, 2447 png_inforp info_ptr, png_fixed_point int_file_gamma)) 2448 #endif 2449 2450 #ifdef PNG_hIST_SUPPORTED 2451 PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr, 2452 png_inforp info_ptr, png_uint_16p *hist)); 2453 #endif 2454 2455 #ifdef PNG_hIST_SUPPORTED 2456 PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr, 2457 png_inforp info_ptr, png_const_uint_16p hist)); 2458 #endif 2459 2460 PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr, 2461 png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, 2462 int *bit_depth, int *color_type, int *interlace_method, 2463 int *compression_method, int *filter_method)); 2464 2465 PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr, 2466 png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, 2467 int color_type, int interlace_method, int compression_method, 2468 int filter_method)); 2469 2470 #ifdef PNG_oFFs_SUPPORTED 2471 PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr, 2472 png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, 2473 int *unit_type)); 2474 #endif 2475 2476 #ifdef PNG_oFFs_SUPPORTED 2477 PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr, 2478 png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y, 2479 int unit_type)); 2480 #endif 2481 2482 #ifdef PNG_pCAL_SUPPORTED 2483 PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr, 2484 png_inforp info_ptr, png_charp *purpose, png_int_32 *X0, 2485 png_int_32 *X1, int *type, int *nparams, png_charp *units, 2486 png_charpp *params)); 2487 #endif 2488 2489 #ifdef PNG_pCAL_SUPPORTED 2490 PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr, 2491 png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1, 2492 int type, int nparams, png_const_charp units, png_charpp params)); 2493 #endif 2494 2495 #ifdef PNG_pHYs_SUPPORTED 2496 PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr, 2497 png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, 2498 int *unit_type)); 2499 #endif 2500 2501 #ifdef PNG_pHYs_SUPPORTED 2502 PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr, 2503 png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); 2504 #endif 2505 2506 PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr, 2507 png_inforp info_ptr, png_colorp *palette, int *num_palette)); 2508 2509 PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr, 2510 png_inforp info_ptr, png_const_colorp palette, int num_palette)); 2511 2512 #ifdef PNG_sBIT_SUPPORTED 2513 PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr, 2514 png_inforp info_ptr, png_color_8p *sig_bit)); 2515 #endif 2516 2517 #ifdef PNG_sBIT_SUPPORTED 2518 PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr, 2519 png_inforp info_ptr, png_const_color_8p sig_bit)); 2520 #endif 2521 2522 #ifdef PNG_sRGB_SUPPORTED 2523 PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr, 2524 png_const_inforp info_ptr, int *file_srgb_intent)); 2525 #endif 2526 2527 #ifdef PNG_sRGB_SUPPORTED 2528 PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr, 2529 png_inforp info_ptr, int srgb_intent)); 2530 PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr, 2531 png_inforp info_ptr, int srgb_intent)); 2532 #endif 2533 2534 #ifdef PNG_iCCP_SUPPORTED 2535 PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr, 2536 png_inforp info_ptr, png_charpp name, int *compression_type, 2537 png_bytepp profile, png_uint_32 *proflen)); 2538 #endif 2539 2540 #ifdef PNG_iCCP_SUPPORTED 2541 PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr, 2542 png_inforp info_ptr, png_const_charp name, int compression_type, 2543 png_const_bytep profile, png_uint_32 proflen)); 2544 #endif 2545 2546 #ifdef PNG_sPLT_SUPPORTED 2547 PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr, 2548 png_inforp info_ptr, png_sPLT_tpp entries)); 2549 #endif 2550 2551 #ifdef PNG_sPLT_SUPPORTED 2552 PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr, 2553 png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)); 2554 #endif 2555 2556 #ifdef PNG_TEXT_SUPPORTED 2557 /* png_get_text also returns the number of text chunks in *num_text */ 2558 PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr, 2559 png_inforp info_ptr, png_textp *text_ptr, int *num_text)); 2560 #endif 2561 2562 /* Note while png_set_text() will accept a structure whose text, 2563 * language, and translated keywords are NULL pointers, the structure 2564 * returned by png_get_text will always contain regular 2565 * zero-terminated C strings. They might be empty strings but 2566 * they will never be NULL pointers. 2567 */ 2568 2569 #ifdef PNG_TEXT_SUPPORTED 2570 PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr, 2571 png_inforp info_ptr, png_const_textp text_ptr, int num_text)); 2572 #endif 2573 2574 #ifdef PNG_tIME_SUPPORTED 2575 PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr, 2576 png_inforp info_ptr, png_timep *mod_time)); 2577 #endif 2578 2579 #ifdef PNG_tIME_SUPPORTED 2580 PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr, 2581 png_inforp info_ptr, png_const_timep mod_time)); 2582 #endif 2583 2584 #ifdef PNG_tRNS_SUPPORTED 2585 PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr, 2586 png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans, 2587 png_color_16p *trans_color)); 2588 #endif 2589 2590 #ifdef PNG_tRNS_SUPPORTED 2591 PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr, 2592 png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans, 2593 png_const_color_16p trans_color)); 2594 #endif 2595 2596 #ifdef PNG_sCAL_SUPPORTED 2597 PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr, 2598 png_const_inforp info_ptr, int *unit, double *width, double *height)) 2599 #if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \ 2600 defined(PNG_FLOATING_POINT_SUPPORTED) 2601 /* NOTE: this API is currently implemented using floating point arithmetic, 2602 * consequently it can only be used on systems with floating point support. 2603 * In any case the range of values supported by png_fixed_point is small and it 2604 * is highly recommended that png_get_sCAL_s be used instead. 2605 */ 2606 PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, 2607 (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, 2608 png_fixed_point *width, png_fixed_point *height)) 2609 #endif 2610 PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, 2611 (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, 2612 png_charpp swidth, png_charpp sheight)); 2613 2614 PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr, 2615 png_inforp info_ptr, int unit, double width, double height)) 2616 PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr, 2617 png_inforp info_ptr, int unit, png_fixed_point width, 2618 png_fixed_point height)) 2619 PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr, 2620 png_inforp info_ptr, int unit, 2621 png_const_charp swidth, png_const_charp sheight)); 2622 #endif /* PNG_sCAL_SUPPORTED */ 2623 2624 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED 2625 /* Provide the default handling for all unknown chunks or, optionally, for 2626 * specific unknown chunks. 2627 * 2628 * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was 2629 * ignored and the default was used, the per-chunk setting only had an effect on 2630 * write. If you wish to have chunk-specific handling on read in code that must 2631 * work on earlier versions you must use a user chunk callback to specify the 2632 * desired handling (keep or discard.) 2633 * 2634 * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The 2635 * parameter is interpreted as follows: 2636 * 2637 * READ: 2638 * PNG_HANDLE_CHUNK_AS_DEFAULT: 2639 * Known chunks: do normal libpng processing, do not keep the chunk (but 2640 * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED) 2641 * Unknown chunks: for a specific chunk use the global default, when used 2642 * as the default discard the chunk data. 2643 * PNG_HANDLE_CHUNK_NEVER: 2644 * Discard the chunk data. 2645 * PNG_HANDLE_CHUNK_IF_SAFE: 2646 * Keep the chunk data if the chunk is not critical else raise a chunk 2647 * error. 2648 * PNG_HANDLE_CHUNK_ALWAYS: 2649 * Keep the chunk data. 2650 * 2651 * If the chunk data is saved it can be retrieved using png_get_unknown_chunks, 2652 * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent 2653 * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks 2654 * it simply resets the behavior to the libpng default. 2655 * 2656 * INTERACTION WTIH USER CHUNK CALLBACKS: 2657 * The per-chunk handling is always used when there is a png_user_chunk_ptr 2658 * callback and the callback returns 0; the chunk is then always stored *unless* 2659 * it is critical and the per-chunk setting is other than ALWAYS. Notice that 2660 * the global default is *not* used in this case. (In effect the per-chunk 2661 * value is incremented to at least IF_SAFE.) 2662 * 2663 * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and 2664 * per-chunk defaults will be honored. If you want to preserve the current 2665 * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE 2666 * as the default - if you don't do this libpng 1.6 will issue a warning. 2667 * 2668 * If you want unhandled unknown chunks to be discarded in libpng 1.6 and 2669 * earlier simply return '1' (handled). 2670 * 2671 * PNG_HANDLE_AS_UNKNOWN_SUPPORTED: 2672 * If this is *not* set known chunks will always be handled by libpng and 2673 * will never be stored in the unknown chunk list. Known chunks listed to 2674 * png_set_keep_unknown_chunks will have no effect. If it is set then known 2675 * chunks listed with a keep other than AS_DEFAULT will *never* be processed 2676 * by libpng, in addition critical chunks must either be processed by the 2677 * callback or saved. 2678 * 2679 * The IHDR and IEND chunks must not be listed. Because this turns off the 2680 * default handling for chunks that would otherwise be recognized the 2681 * behavior of libpng transformations may well become incorrect! 2682 * 2683 * WRITE: 2684 * When writing chunks the options only apply to the chunks specified by 2685 * png_set_unknown_chunks (below), libpng will *always* write known chunks 2686 * required by png_set_ calls and will always write the core critical chunks 2687 * (as required for PLTE). 2688 * 2689 * Each chunk in the png_set_unknown_chunks list is looked up in the 2690 * png_set_keep_unknown_chunks list to find the keep setting, this is then 2691 * interpreted as follows: 2692 * 2693 * PNG_HANDLE_CHUNK_AS_DEFAULT: 2694 * Write safe-to-copy chunks and write other chunks if the global 2695 * default is set to _ALWAYS, otherwise don't write this chunk. 2696 * PNG_HANDLE_CHUNK_NEVER: 2697 * Do not write the chunk. 2698 * PNG_HANDLE_CHUNK_IF_SAFE: 2699 * Write the chunk if it is safe-to-copy, otherwise do not write it. 2700 * PNG_HANDLE_CHUNK_ALWAYS: 2701 * Write the chunk. 2702 * 2703 * Note that the default behavior is effectively the opposite of the read case - 2704 * in read unknown chunks are not stored by default, in write they are written 2705 * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different 2706 * - on write the safe-to-copy bit is checked, on read the critical bit is 2707 * checked and on read if the chunk is critical an error will be raised. 2708 * 2709 * num_chunks: 2710 * =========== 2711 * If num_chunks is positive, then the "keep" parameter specifies the manner 2712 * for handling only those chunks appearing in the chunk_list array, 2713 * otherwise the chunk list array is ignored. 2714 * 2715 * If num_chunks is 0 the "keep" parameter specifies the default behavior for 2716 * unknown chunks, as described above. 2717 * 2718 * If num_chunks is negative, then the "keep" parameter specifies the manner 2719 * for handling all unknown chunks plus all chunks recognized by libpng 2720 * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to 2721 * be processed by libpng. 2722 */ 2723 PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr, 2724 int keep, png_const_bytep chunk_list, int num_chunks)); 2725 2726 /* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned; 2727 * the result is therefore true (non-zero) if special handling is required, 2728 * false for the default handling. 2729 */ 2730 PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr, 2731 png_const_bytep chunk_name)); 2732 #endif 2733 2734 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED 2735 PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr, 2736 png_inforp info_ptr, png_const_unknown_chunkp unknowns, 2737 int num_unknowns)); 2738 /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added 2739 * unknowns to the location currently stored in the png_struct. This is 2740 * invariably the wrong value on write. To fix this call the following API 2741 * for each chunk in the list with the correct location. If you know your 2742 * code won't be compiled on earlier versions you can rely on 2743 * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing 2744 * the correct thing. 2745 */ 2746 2747 PNG_EXPORT(175, void, png_set_unknown_chunk_location, 2748 (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location)); 2749 2750 PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr, 2751 png_inforp info_ptr, png_unknown_chunkpp entries)); 2752 #endif 2753 2754 /* Png_free_data() will turn off the "valid" flag for anything it frees. 2755 * If you need to turn it off for a chunk that your application has freed, 2756 * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); 2757 */ 2758 PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr, 2759 png_inforp info_ptr, int mask)); 2760 2761 #ifdef PNG_INFO_IMAGE_SUPPORTED 2762 /* The "params" pointer is currently not used and is for future expansion. */ 2763 PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr, 2764 int transforms, png_voidp params)); 2765 PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr, 2766 int transforms, png_voidp params)); 2767 #endif 2768 2769 PNG_EXPORT(180, png_const_charp, png_get_copyright, 2770 (png_const_structrp png_ptr)); 2771 PNG_EXPORT(181, png_const_charp, png_get_header_ver, 2772 (png_const_structrp png_ptr)); 2773 PNG_EXPORT(182, png_const_charp, png_get_header_version, 2774 (png_const_structrp png_ptr)); 2775 PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, 2776 (png_const_structrp png_ptr)); 2777 2778 #ifdef PNG_MNG_FEATURES_SUPPORTED 2779 PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr, 2780 png_uint_32 mng_features_permitted)); 2781 #endif 2782 2783 /* For use in png_set_keep_unknown, added to version 1.2.6 */ 2784 #define PNG_HANDLE_CHUNK_AS_DEFAULT 0 2785 #define PNG_HANDLE_CHUNK_NEVER 1 2786 #define PNG_HANDLE_CHUNK_IF_SAFE 2 2787 #define PNG_HANDLE_CHUNK_ALWAYS 3 2788 #define PNG_HANDLE_CHUNK_LAST 4 2789 2790 /* Strip the prepended error numbers ("#nnn ") from error and warning 2791 * messages before passing them to the error or warning handler. 2792 */ 2793 #ifdef PNG_ERROR_NUMBERS_SUPPORTED 2794 PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr, 2795 png_uint_32 strip_mode)); 2796 #endif 2797 2798 /* Added in libpng-1.2.6 */ 2799 #ifdef PNG_SET_USER_LIMITS_SUPPORTED 2800 PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr, 2801 png_uint_32 user_width_max, png_uint_32 user_height_max)); 2802 PNG_EXPORT(187, png_uint_32, png_get_user_width_max, 2803 (png_const_structrp png_ptr)); 2804 PNG_EXPORT(188, png_uint_32, png_get_user_height_max, 2805 (png_const_structrp png_ptr)); 2806 /* Added in libpng-1.4.0 */ 2807 PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr, 2808 png_uint_32 user_chunk_cache_max)); 2809 PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, 2810 (png_const_structrp png_ptr)); 2811 /* Added in libpng-1.4.1 */ 2812 PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr, 2813 png_alloc_size_t user_chunk_cache_max)); 2814 PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, 2815 (png_const_structrp png_ptr)); 2816 #endif 2817 2818 #if defined(PNG_INCH_CONVERSIONS_SUPPORTED) 2819 PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, 2820 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2821 2822 PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, 2823 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2824 2825 PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, 2826 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2827 2828 PNG_FP_EXPORT(196, float, png_get_x_offset_inches, 2829 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2830 #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ 2831 PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, 2832 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2833 #endif 2834 2835 PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr, 2836 png_const_inforp info_ptr)) 2837 #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ 2838 PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, 2839 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2840 #endif 2841 2842 # ifdef PNG_pHYs_SUPPORTED 2843 PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr, 2844 png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, 2845 int *unit_type)); 2846 # endif /* PNG_pHYs_SUPPORTED */ 2847 #endif /* PNG_INCH_CONVERSIONS_SUPPORTED */ 2848 2849 /* Added in libpng-1.4.0 */ 2850 #ifdef PNG_IO_STATE_SUPPORTED 2851 PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr)); 2852 2853 /* Removed from libpng 1.6; use png_get_io_chunk_type. */ 2854 PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr), 2855 PNG_DEPRECATED) 2856 2857 PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, 2858 (png_const_structrp png_ptr)); 2859 2860 /* The flags returned by png_get_io_state() are the following: */ 2861 # define PNG_IO_NONE 0x0000 /* no I/O at this moment */ 2862 # define PNG_IO_READING 0x0001 /* currently reading */ 2863 # define PNG_IO_WRITING 0x0002 /* currently writing */ 2864 # define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ 2865 # define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ 2866 # define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ 2867 # define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ 2868 # define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ 2869 # define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ 2870 #endif /* ?PNG_IO_STATE_SUPPORTED */ 2871 2872 /* Interlace support. The following macros are always defined so that if 2873 * libpng interlace handling is turned off the macros may be used to handle 2874 * interlaced images within the application. 2875 */ 2876 #define PNG_INTERLACE_ADAM7_PASSES 7 2877 2878 /* Two macros to return the first row and first column of the original, 2879 * full, image which appears in a given pass. 'pass' is in the range 0 2880 * to 6 and the result is in the range 0 to 7. 2881 */ 2882 #define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) 2883 #define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) 2884 2885 /* A macro to return the offset between pixels in the output row for a pair of 2886 * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that 2887 * follows. Note that ROW_OFFSET is the offset from one row to the next whereas 2888 * COL_OFFSET is from one column to the next, within a row. 2889 */ 2890 #define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) 2891 #define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) 2892 2893 /* Two macros to help evaluate the number of rows or columns in each 2894 * pass. This is expressed as a shift - effectively log2 of the number or 2895 * rows or columns in each 8x8 tile of the original image. 2896 */ 2897 #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) 2898 #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) 2899 2900 /* Hence two macros to determine the number of rows or columns in a given 2901 * pass of an image given its height or width. In fact these macros may 2902 * return non-zero even though the sub-image is empty, because the other 2903 * dimension may be empty for a small image. 2904 */ 2905 #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ 2906 -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) 2907 #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ 2908 -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) 2909 2910 /* For the reader row callbacks (both progressive and sequential) it is 2911 * necessary to find the row in the output image given a row in an interlaced 2912 * image, so two more macros: 2913 */ 2914 #define PNG_ROW_FROM_PASS_ROW(y_in, pass) \ 2915 (((y_in)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) 2916 #define PNG_COL_FROM_PASS_COL(x_in, pass) \ 2917 (((x_in)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) 2918 2919 /* Two macros which return a boolean (0 or 1) saying whether the given row 2920 * or column is in a particular pass. These use a common utility macro that 2921 * returns a mask for a given pass - the offset 'off' selects the row or 2922 * column version. The mask has the appropriate bit set for each column in 2923 * the tile. 2924 */ 2925 #define PNG_PASS_MASK(pass,off) ( \ 2926 ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \ 2927 ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) 2928 2929 #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ 2930 ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) 2931 #define PNG_COL_IN_INTERLACE_PASS(x, pass) \ 2932 ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) 2933 2934 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED 2935 /* With these routines we avoid an integer divide, which will be slower on 2936 * most machines. However, it does take more operations than the corresponding 2937 * divide method, so it may be slower on a few RISC systems. There are two 2938 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. 2939 * 2940 * Note that the rounding factors are NOT supposed to be the same! 128 and 2941 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the 2942 * standard method. 2943 * 2944 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] 2945 */ 2946 2947 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ 2948 2949 # define png_composite(composite, fg, alpha, bg) \ 2950 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ 2951 * (png_uint_16)(alpha) \ 2952 + (png_uint_16)(bg)*(png_uint_16)(255 \ 2953 - (png_uint_16)(alpha)) + 128); \ 2954 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } 2955 2956 # define png_composite_16(composite, fg, alpha, bg) \ 2957 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ 2958 * (png_uint_32)(alpha) \ 2959 + (png_uint_32)(bg)*(65535 \ 2960 - (png_uint_32)(alpha)) + 32768); \ 2961 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } 2962 2963 #else /* Standard method using integer division */ 2964 2965 # define png_composite(composite, fg, alpha, bg) \ 2966 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ 2967 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ 2968 127) / 255) 2969 2970 # define png_composite_16(composite, fg, alpha, bg) \ 2971 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ 2972 (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ 2973 32767) / 65535) 2974 #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */ 2975 2976 #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED 2977 PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); 2978 PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); 2979 PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); 2980 #endif 2981 2982 PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr, 2983 png_const_bytep buf)); 2984 /* No png_get_int_16 -- may be added if there's a real need for it. */ 2985 2986 /* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ 2987 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED 2988 PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); 2989 #endif 2990 #ifdef PNG_SAVE_INT_32_SUPPORTED 2991 PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); 2992 #endif 2993 2994 /* Place a 16-bit number into a buffer in PNG byte order. 2995 * The parameter is declared unsigned int, not png_uint_16, 2996 * just to avoid potential problems on pre-ANSI C compilers. 2997 */ 2998 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED 2999 PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); 3000 /* No png_save_int_16 -- may be added if there's a real need for it. */ 3001 #endif 3002 3003 #ifdef PNG_USE_READ_MACROS 3004 /* Inline macros to do direct reads of bytes from the input buffer. 3005 * The png_get_int_32() routine assumes we are using two's complement 3006 * format for negative values, which is almost certainly true. 3007 */ 3008 # define PNG_get_uint_32(buf) \ 3009 (((png_uint_32)(*(buf)) << 24) + \ 3010 ((png_uint_32)(*((buf) + 1)) << 16) + \ 3011 ((png_uint_32)(*((buf) + 2)) << 8) + \ 3012 ((png_uint_32)(*((buf) + 3)))) 3013 3014 /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the 3015 * function) incorrectly returned a value of type png_uint_32. 3016 */ 3017 # define PNG_get_uint_16(buf) \ 3018 ((png_uint_16) \ 3019 (((unsigned int)(*(buf)) << 8) + \ 3020 ((unsigned int)(*((buf) + 1))))) 3021 3022 # define PNG_get_int_32(buf) \ 3023 ((png_int_32)((*(buf) & 0x80) \ 3024 ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \ 3025 : (png_int_32)png_get_uint_32(buf))) 3026 3027 /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h, 3028 * but defining a macro name prefixed with PNG_PREFIX. 3029 */ 3030 # ifndef PNG_PREFIX 3031 # define png_get_uint_32(buf) PNG_get_uint_32(buf) 3032 # define png_get_uint_16(buf) PNG_get_uint_16(buf) 3033 # define png_get_int_32(buf) PNG_get_int_32(buf) 3034 # endif 3035 #else 3036 # ifdef PNG_PREFIX 3037 /* No macros; revert to the (redefined) function */ 3038 # define PNG_get_uint_32 (png_get_uint_32) 3039 # define PNG_get_uint_16 (png_get_uint_16) 3040 # define PNG_get_int_32 (png_get_int_32) 3041 # endif 3042 #endif 3043 3044 /******************************************************************************* 3045 * SIMPLIFIED API 3046 ******************************************************************************* 3047 * 3048 * Please read the documentation in libpng-manual.txt (TODO: write said 3049 * documentation) if you don't understand what follows. 3050 * 3051 * The simplified API hides the details of both libpng and the PNG file format 3052 * itself. It allows PNG files to be read into a very limited number of 3053 * in-memory bitmap formats or to be written from the same formats. If these 3054 * formats do not accomodate your needs then you can, and should, use the more 3055 * sophisticated APIs above - these support a wide variety of in-memory formats 3056 * and a wide variety of sophisticated transformations to those formats as well 3057 * as a wide variety of APIs to manipulate ancillary information. 3058 * 3059 * To read a PNG file using the simplified API: 3060 * 3061 * 1) Declare a 'png_image' structure (see below) on the stack and set the 3062 * version field to PNG_IMAGE_VERSION. 3063 * 2) Call the appropriate png_image_begin_read... function. 3064 * 3) Set the png_image 'format' member to the required sample format. 3065 * 4) Allocate a buffer for the image and, if required, the color-map. 3066 * 5) Call png_image_finish_read to read the image and, if required, the 3067 * color-map into your buffers. 3068 * 3069 * There are no restrictions on the format of the PNG input itself; all valid 3070 * color types, bit depths, and interlace methods are acceptable, and the 3071 * input image is transformed as necessary to the requested in-memory format 3072 * during the png_image_finish_read() step. The only caveat is that if you 3073 * request a color-mapped image from a PNG that is full-color or makes 3074 * complex use of an alpha channel the transformation is extremely lossy and the 3075 * result may look terrible. 3076 * 3077 * To write a PNG file using the simplified API: 3078 * 3079 * 1) Declare a 'png_image' structure on the stack and memset() it to all zero. 3080 * 2) Initialize the members of the structure that describe the image, setting 3081 * the 'format' member to the format of the image samples. 3082 * 3) Call the appropriate png_image_write... function with a pointer to the 3083 * image and, if necessary, the color-map to write the PNG data. 3084 * 3085 * png_image is a structure that describes the in-memory format of an image 3086 * when it is being read or defines the in-memory format of an image that you 3087 * need to write: 3088 */ 3089 #define PNG_IMAGE_VERSION 1 3090 3091 typedef struct png_control *png_controlp; 3092 typedef struct 3093 { 3094 png_controlp opaque; /* Initialize to NULL, free with png_image_free */ 3095 png_uint_32 version; /* Set to PNG_IMAGE_VERSION */ 3096 png_uint_32 width; /* Image width in pixels (columns) */ 3097 png_uint_32 height; /* Image height in pixels (rows) */ 3098 png_uint_32 format; /* Image format as defined below */ 3099 png_uint_32 flags; /* A bit mask containing informational flags */ 3100 png_uint_32 colormap_entries; 3101 /* Number of entries in the color-map */ 3102 3103 /* In the event of an error or warning the following field will be set to a 3104 * non-zero value and the 'message' field will contain a '\0' terminated 3105 * string with the libpng error or warning message. If both warnings and 3106 * an error were encountered, only the error is recorded. If there 3107 * are multiple warnings, only the first one is recorded. 3108 * 3109 * The upper 30 bits of this value are reserved, the low two bits contain 3110 * a value as follows: 3111 */ 3112 # define PNG_IMAGE_WARNING 1 3113 # define PNG_IMAGE_ERROR 2 3114 /* 3115 * The result is a two bit code such that a value more than 1 indicates 3116 * a failure in the API just called: 3117 * 3118 * 0 - no warning or error 3119 * 1 - warning 3120 * 2 - error 3121 * 3 - error preceded by warning 3122 */ 3123 # define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1) 3124 3125 png_uint_32 warning_or_error; 3126 3127 char message[64]; 3128 } png_image, *png_imagep; 3129 3130 /* The samples of the image have one to four channels whose components have 3131 * original values in the range 0 to 1.0: 3132 * 3133 * 1: A single gray or luminance channel (G). 3134 * 2: A gray/luminance channel and an alpha channel (GA). 3135 * 3: Three red, green, blue color channels (RGB). 3136 * 4: Three color channels and an alpha channel (RGBA). 3137 * 3138 * The components are encoded in one of two ways: 3139 * 3140 * a) As a small integer, value 0..255, contained in a single byte. For the 3141 * alpha channel the original value is simply value/255. For the color or 3142 * luminance channels the value is encoded according to the sRGB specification 3143 * and matches the 8-bit format expected by typical display devices. 3144 * 3145 * The color/gray channels are not scaled (pre-multiplied) by the alpha 3146 * channel and are suitable for passing to color management software. 3147 * 3148 * b) As a value in the range 0..65535, contained in a 2-byte integer. All 3149 * channels can be converted to the original value by dividing by 65535; all 3150 * channels are linear. Color channels use the RGB encoding (RGB end-points) of 3151 * the sRGB specification. This encoding is identified by the 3152 * PNG_FORMAT_FLAG_LINEAR flag below. 3153 * 3154 * When the simplified API needs to convert between sRGB and linear colorspaces, 3155 * the actual sRGB transfer curve defined in the sRGB specification (see the 3156 * article at http://en.wikipedia.org/wiki/SRGB) is used, not the gamma=1/2.2 3157 * approximation used elsewhere in libpng. 3158 * 3159 * When an alpha channel is present it is expected to denote pixel coverage 3160 * of the color or luminance channels and is returned as an associated alpha 3161 * channel: the color/gray channels are scaled (pre-multiplied) by the alpha 3162 * value. 3163 * 3164 * The samples are either contained directly in the image data, between 1 and 8 3165 * bytes per pixel according to the encoding, or are held in a color-map indexed 3166 * by bytes in the image data. In the case of a color-map the color-map entries 3167 * are individual samples, encoded as above, and the image data has one byte per 3168 * pixel to select the relevant sample from the color-map. 3169 */ 3170 3171 /* PNG_FORMAT_* 3172 * 3173 * #defines to be used in png_image::format. Each #define identifies a 3174 * particular layout of sample data and, if present, alpha values. There are 3175 * separate defines for each of the two component encodings. 3176 * 3177 * A format is built up using single bit flag values. All combinations are 3178 * valid. Formats can be built up from the flag values or you can use one of 3179 * the predefined values below. When testing formats always use the FORMAT_FLAG 3180 * macros to test for individual features - future versions of the library may 3181 * add new flags. 3182 * 3183 * When reading or writing color-mapped images the format should be set to the 3184 * format of the entries in the color-map then png_image_{read,write}_colormap 3185 * called to read or write the color-map and set the format correctly for the 3186 * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly! 3187 * 3188 * NOTE: libpng can be built with particular features disabled, if you see 3189 * compiler errors because the definition of one of the following flags has been 3190 * compiled out it is because libpng does not have the required support. It is 3191 * possible, however, for the libpng configuration to enable the format on just 3192 * read or just write; in that case you may see an error at run time. You can 3193 * guard against this by checking for the definition of the appropriate 3194 * "_SUPPORTED" macro, one of: 3195 * 3196 * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED 3197 */ 3198 #define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */ 3199 #define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */ 3200 #define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2 byte channels else 1 byte */ 3201 #define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */ 3202 3203 #ifdef PNG_FORMAT_BGR_SUPPORTED 3204 # define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */ 3205 #endif 3206 3207 #ifdef PNG_FORMAT_AFIRST_SUPPORTED 3208 # define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */ 3209 #endif 3210 3211 /* Commonly used formats have predefined macros. 3212 * 3213 * First the single byte (sRGB) formats: 3214 */ 3215 #define PNG_FORMAT_GRAY 0 3216 #define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA 3217 #define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST) 3218 #define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR 3219 #define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR) 3220 #define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA) 3221 #define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST) 3222 #define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA) 3223 #define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST) 3224 3225 /* Then the linear 2-byte formats. When naming these "Y" is used to 3226 * indicate a luminance (gray) channel. 3227 */ 3228 #define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR 3229 #define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA) 3230 #define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR) 3231 #define PNG_FORMAT_LINEAR_RGB_ALPHA \ 3232 (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA) 3233 3234 /* With color-mapped formats the image data is one byte for each pixel, the byte 3235 * is an index into the color-map which is formatted as above. To obtain a 3236 * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP 3237 * to one of the above definitions, or you can use one of the definitions below. 3238 */ 3239 #define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP) 3240 #define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP) 3241 #define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP) 3242 #define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP) 3243 #define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP) 3244 #define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP) 3245 3246 /* PNG_IMAGE macros 3247 * 3248 * These are convenience macros to derive information from a png_image 3249 * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the 3250 * actual image sample values - either the entries in the color-map or the 3251 * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values 3252 * for the pixels and will always return 1 for color-mapped formats. The 3253 * remaining macros return information about the rows in the image and the 3254 * complete image. 3255 * 3256 * NOTE: All the macros that take a png_image::format parameter are compile time 3257 * constants if the format parameter is, itself, a constant. Therefore these 3258 * macros can be used in array declarations and case labels where required. 3259 * Similarly the macros are also pre-processor constants (sizeof is not used) so 3260 * they can be used in #if tests. 3261 * 3262 * First the information about the samples. 3263 */ 3264 #define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\ 3265 (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1) 3266 /* Return the total number of channels in a given format: 1..4 */ 3267 3268 #define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\ 3269 ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1) 3270 /* Return the size in bytes of a single component of a pixel or color-map 3271 * entry (as appropriate) in the image: 1 or 2. 3272 */ 3273 3274 #define PNG_IMAGE_SAMPLE_SIZE(fmt)\ 3275 (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)) 3276 /* This is the size of the sample data for one sample. If the image is 3277 * color-mapped it is the size of one color-map entry (and image pixels are 3278 * one byte in size), otherwise it is the size of one image pixel. 3279 */ 3280 3281 #define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\ 3282 (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256) 3283 /* The maximum size of the color-map required by the format expressed in a 3284 * count of components. This can be used to compile-time allocate a 3285 * color-map: 3286 * 3287 * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)]; 3288 * 3289 * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)]; 3290 * 3291 * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the 3292 * information from one of the png_image_begin_read_ APIs and dynamically 3293 * allocate the required memory. 3294 */ 3295 3296 /* Corresponding information about the pixels */ 3297 #define PNG_IMAGE_PIXEL_(test,fmt)\ 3298 (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt)) 3299 3300 #define PNG_IMAGE_PIXEL_CHANNELS(fmt)\ 3301 PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt) 3302 /* The number of separate channels (components) in a pixel; 1 for a 3303 * color-mapped image. 3304 */ 3305 3306 #define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\ 3307 PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt) 3308 /* The size, in bytes, of each component in a pixel; 1 for a color-mapped 3309 * image. 3310 */ 3311 3312 #define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt) 3313 /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */ 3314 3315 /* Information about the whole row, or whole image */ 3316 #define PNG_IMAGE_ROW_STRIDE(image)\ 3317 (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width) 3318 /* Return the total number of components in a single row of the image; this 3319 * is the minimum 'row stride', the minimum count of components between each 3320 * row. For a color-mapped image this is the minimum number of bytes in a 3321 * row. 3322 */ 3323 3324 #define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\ 3325 (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride)) 3326 /* Return the size, in bytes, of an image buffer given a png_image and a row 3327 * stride - the number of components to leave space for in each row. 3328 */ 3329 3330 #define PNG_IMAGE_SIZE(image)\ 3331 PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image)) 3332 /* Return the size, in bytes, of the image in memory given just a png_image; 3333 * the row stride is the minimum stride required for the image. 3334 */ 3335 3336 #define PNG_IMAGE_COLORMAP_SIZE(image)\ 3337 (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries) 3338 /* Return the size, in bytes, of the color-map of this image. If the image 3339 * format is not a color-map format this will return a size sufficient for 3340 * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if 3341 * you don't want to allocate a color-map in this case. 3342 */ 3343 3344 /* PNG_IMAGE_FLAG_* 3345 * 3346 * Flags containing additional information about the image are held in the 3347 * 'flags' field of png_image. 3348 */ 3349 #define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01 3350 /* This indicates the the RGB values of the in-memory bitmap do not 3351 * correspond to the red, green and blue end-points defined by sRGB. 3352 */ 3353 3354 #define PNG_IMAGE_FLAG_FAST 0x02 3355 /* On write emphasise speed over compression; the resultant PNG file will be 3356 * larger but will be produced significantly faster, particular for large 3357 * images. Do not use this option for images which will be distributed, only 3358 * used it when producing intermediate files that will be read back in 3359 * repeatedly. For a typical 24-bit image the option will double the read 3360 * speed at the cost of increasing the image size by 25%, however for many 3361 * more compressible images the PNG file can be 10 times larger with only a 3362 * slight speed gain. 3363 */ 3364 3365 #define PNG_IMAGE_FLAG_16BIT_sRGB 0x04 3366 /* On read if the image is a 16-bit per component image and there is no gAMA 3367 * or sRGB chunk assume that the components are sRGB encoded. Notice that 3368 * images output by the simplified API always have gamma information; setting 3369 * this flag only affects the interpretation of 16-bit images from an 3370 * external source. It is recommended that the application expose this flag 3371 * to the user; the user can normally easily recognize the difference between 3372 * linear and sRGB encoding. This flag has no effect on write - the data 3373 * passed to the write APIs must have the correct encoding (as defined 3374 * above.) 3375 * 3376 * If the flag is not set (the default) input 16-bit per component data is 3377 * assumed to be linear. 3378 * 3379 * NOTE: the flag can only be set after the png_image_begin_read_ call, 3380 * because that call initializes the 'flags' field. 3381 */ 3382 3383 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED 3384 /* READ APIs 3385 * --------- 3386 * 3387 * The png_image passed to the read APIs must have been initialized by setting 3388 * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.) 3389 */ 3390 #ifdef PNG_STDIO_SUPPORTED 3391 PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image, 3392 const char *file_name)); 3393 /* The named file is opened for read and the image header is filled in 3394 * from the PNG header in the file. 3395 */ 3396 3397 PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image, 3398 FILE* file)); 3399 /* The PNG header is read from the stdio FILE object. */ 3400 #endif /* PNG_STDIO_SUPPORTED */ 3401 3402 PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image, 3403 png_const_voidp memory, png_size_t size)); 3404 /* The PNG header is read from the given memory buffer. */ 3405 3406 PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image, 3407 png_const_colorp background, void *buffer, png_int_32 row_stride, 3408 void *colormap)); 3409 /* Finish reading the image into the supplied buffer and clean up the 3410 * png_image structure. 3411 * 3412 * row_stride is the step, in byte or 2-byte units as appropriate, 3413 * between adjacent rows. A positive stride indicates that the top-most row 3414 * is first in the buffer - the normal top-down arrangement. A negative 3415 * stride indicates that the bottom-most row is first in the buffer. 3416 * 3417 * background need only be supplied if an alpha channel must be removed from 3418 * a png_byte format and the removal is to be done by compositing on a solid 3419 * color; otherwise it may be NULL and any composition will be done directly 3420 * onto the buffer. The value is an sRGB color to use for the background, 3421 * for grayscale output the green channel is used. 3422 * 3423 * background must be supplied when an alpha channel must be removed from a 3424 * single byte color-mapped output format, in other words if: 3425 * 3426 * 1) The original format from png_image_begin_read_from_* had 3427 * PNG_FORMAT_FLAG_ALPHA set. 3428 * 2) The format set by the application does not. 3429 * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and 3430 * PNG_FORMAT_FLAG_LINEAR *not* set. 3431 * 3432 * For linear output removing the alpha channel is always done by compositing 3433 * on black and background is ignored. 3434 * 3435 * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must 3436 * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE. 3437 * image->colormap_entries will be updated to the actual number of entries 3438 * written to the colormap; this may be less than the original value. 3439 */ 3440 3441 PNG_EXPORT(238, void, png_image_free, (png_imagep image)); 3442 /* Free any data allocated by libpng in image->opaque, setting the pointer to 3443 * NULL. May be called at any time after the structure is initialized. 3444 */ 3445 #endif /* PNG_SIMPLIFIED_READ_SUPPORTED */ 3446 3447 #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED 3448 #ifdef PNG_STDIO_SUPPORTED 3449 /* WRITE APIS 3450 * ---------- 3451 * For write you must initialize a png_image structure to describe the image to 3452 * be written. To do this use memset to set the whole structure to 0 then 3453 * initialize fields describing your image. 3454 * 3455 * version: must be set to PNG_IMAGE_VERSION 3456 * opaque: must be initialized to NULL 3457 * width: image width in pixels 3458 * height: image height in rows 3459 * format: the format of the data (image and color-map) you wish to write 3460 * flags: set to 0 unless one of the defined flags applies; set 3461 * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB 3462 * values do not correspond to the colors in sRGB. 3463 * colormap_entries: set to the number of entries in the color-map (0 to 256) 3464 */ 3465 PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image, 3466 const char *file, int convert_to_8bit, const void *buffer, 3467 png_int_32 row_stride, const void *colormap)); 3468 /* Write the image to the named file. */ 3469 3470 PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file, 3471 int convert_to_8_bit, const void *buffer, png_int_32 row_stride, 3472 const void *colormap)); 3473 /* Write the image to the given (FILE*). */ 3474 3475 /* With both write APIs if image is in one of the linear formats with 16-bit 3476 * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG 3477 * gamma encoded according to the sRGB specification, otherwise a 16-bit linear 3478 * encoded PNG file is written. 3479 * 3480 * With color-mapped data formats the colormap parameter point to a color-map 3481 * with at least image->colormap_entries encoded in the specified format. If 3482 * the format is linear the written PNG color-map will be converted to sRGB 3483 * regardless of the convert_to_8_bit flag. 3484 * 3485 * With all APIs row_stride is handled as in the read APIs - it is the spacing 3486 * from one row to the next in component sized units (1 or 2 bytes) and if 3487 * negative indicates a bottom-up row layout in the buffer. 3488 * 3489 * Note that the write API does not support interlacing or sub-8-bit pixels. 3490 */ 3491 #endif /* PNG_STDIO_SUPPORTED */ 3492 #endif /* PNG_SIMPLIFIED_WRITE_SUPPORTED */ 3493 /******************************************************************************* 3494 * END OF SIMPLIFIED API 3495 ******************************************************************************/ 3496 3497 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED 3498 PNG_EXPORT(242, void, png_set_check_for_invalid_index, 3499 (png_structrp png_ptr, int allowed)); 3500 # ifdef PNG_GET_PALETTE_MAX_SUPPORTED 3501 PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr, 3502 png_const_infop info_ptr)); 3503 # endif 3504 #endif /* CHECK_FOR_INVALID_INDEX */ 3505 3506 /******************************************************************************* 3507 * IMPLEMENTATION OPTIONS 3508 ******************************************************************************* 3509 * 3510 * Support for arbitrary implementation-specific optimizations. The API allows 3511 * particular options to be turned on or off. 'Option' is the number of the 3512 * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given 3513 * by the PNG_OPTION_ defines below. 3514 * 3515 * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions, 3516 * are detected at run time, however sometimes it may be impossible 3517 * to do this in user mode, in which case it is necessary to discover 3518 * the capabilities in an OS specific way. Such capabilities are 3519 * listed here when libpng has support for them and must be turned 3520 * ON by the application if present. 3521 * 3522 * SOFTWARE: sometimes software optimizations actually result in performance 3523 * decrease on some architectures or systems, or with some sets of 3524 * PNG images. 'Software' options allow such optimizations to be 3525 * selected at run time. 3526 */ 3527 #ifdef PNG_SET_OPTION_SUPPORTED 3528 #ifdef PNG_ARM_NEON_API_SUPPORTED 3529 # define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */ 3530 #endif 3531 #define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */ 3532 #define PNG_OPTION_NEXT 4 /* Next option - numbers must be even */ 3533 3534 /* Return values: NOTE: there are four values and 'off' is *not* zero */ 3535 #define PNG_OPTION_UNSET 0 /* Unset - defaults to off */ 3536 #define PNG_OPTION_INVALID 1 /* Option number out of range */ 3537 #define PNG_OPTION_OFF 2 3538 #define PNG_OPTION_ON 3 3539 3540 PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option, 3541 int onoff)); 3542 #endif 3543 3544 /******************************************************************************* 3545 * END OF HARDWARE OPTIONS 3546 ******************************************************************************/ 3547 3548 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project 3549 * defs, scripts/pnglibconf.h, and scripts/pnglibconf.h.prebuilt 3550 */ 3551 3552 /* The last ordinal number (this is the *last* one already used; the next 3553 * one to use is one more than this.) Maintainer, remember to add an entry to 3554 * scripts/symbols.def as well. 3555 */ 3556 #ifdef PNG_EXPORT_LAST_ORDINAL 3557 PNG_EXPORT_LAST_ORDINAL(244); 3558 #endif 3559 3560 #ifdef __cplusplus 3561 } 3562 #endif 3563 3564 #endif /* PNG_VERSION_INFO_ONLY */ 3565 /* Do not put anything past this line */ 3566 #endif /* PNG_H */ 3567
