1 2/* png.h - header file for PNG reference library 3 * 4 * libpng version 1.5.12 - July 11, 2012 5 * Copyright (c) 1998-2012 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 1.5.12 - July 11, 2012: 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 * 1.5.8beta01 15 10508 15.so.15.8[.0] 170 * 1.5.8rc01 15 10508 15.so.15.8[.0] 171 * 1.5.8 15 10508 15.so.15.8[.0] 172 * 1.5.9beta01-02 15 10509 15.so.15.9[.0] 173 * 1.5.9rc01 15 10509 15.so.15.9[.0] 174 * 1.5.9 15 10509 15.so.15.9[.0] 175 * 1.5.10beta01-05 15 10510 15.so.15.10[.0] 176 * 1.5.10 15 10510 15.so.15.10[.0] 177 * 1.5.11beta01 15 10511 15.so.15.11[.0] 178 * 1.5.11rc01-05 15 10511 15.so.15.11[.0] 179 * 1.5.11 15 10511 15.so.15.11[.0] 180 * 1.5.12 15 10512 15.so.15.12[.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 1.5.12, July 11, 2012, are 213 * Copyright (c) 2004, 2006-2012 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 11, 2012 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 1.5.12 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 holds the date in text 335 * 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 will be no 342 * longer used in libpng-1.6.0 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() in png.c 346 * (formerly png_convert_to_rfc_1152() in error) 347 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c 348 * png_convert_from_time_t() in pngwrite.c 349 * png_get_tIME() in pngget.c 350 * png_handle_tIME() in pngrutil.c, called in pngread.c 351 * png_set_tIME() in pngset.c 352 * png_write_tIME() in pngwutil.c, called in pngwrite.c 353 * 354 * All handle dates properly in a Y2K environment. The 355 * png_convert_from_time_t() function calls gmtime() to convert from system 356 * clock time, which returns (year - 1900), which we properly convert to 357 * the full 4-digit year. There is a possibility that applications using 358 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123() 359 * function, or that they are incorrectly passing only a 2-digit year 360 * instead of "year - 1900" into the png_convert_from_struct_tm() function, 361 * but this is not under our control. The libpng documentation has always 362 * stated that it works with 4-digit years, and the APIs have been 363 * documented as such. 364 * 365 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned 366 * integer to hold the year, and can hold years as large as 65535. 367 * 368 * zlib, upon which libpng depends, is also Y2K compliant. It contains 369 * no date-related code. 370 * 371 * Glenn Randers-Pehrson 372 * libpng maintainer 373 * PNG Development Group 374 */ 375 376#ifndef PNG_H 377#define PNG_H 378 379/* This is not the place to learn how to use libpng. The file libpng-manual.txt 380 * describes how to use libpng, and the file example.c summarizes it 381 * with some code on which to build. This file is useful for looking 382 * at the actual function definitions and structure components. 383 * 384 * If you just need to read a PNG file and don't want to read the documentation 385 * skip to the end of this file and read the section entitled 'simplified API'. 386 */ 387 388/* Version information for png.h - this should match the version in png.c */ 389#define PNG_LIBPNG_VER_STRING "1.5.12" 390#define PNG_HEADER_VERSION_STRING \ 391 " libpng version 1.5.12 - July 11, 2012\n" 392 393#define PNG_LIBPNG_VER_SONUM 15 394#define PNG_LIBPNG_VER_DLLNUM 15 395 396/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */ 397#define PNG_LIBPNG_VER_MAJOR 1 398#define PNG_LIBPNG_VER_MINOR 5 399#define PNG_LIBPNG_VER_RELEASE 12 400 401/* This should match the numeric part of the final component of 402 * PNG_LIBPNG_VER_STRING, omitting any leading zero: 403 */ 404 405#define PNG_LIBPNG_VER_BUILD 0 406 407/* Release Status */ 408#define PNG_LIBPNG_BUILD_ALPHA 1 409#define PNG_LIBPNG_BUILD_BETA 2 410#define PNG_LIBPNG_BUILD_RC 3 411#define PNG_LIBPNG_BUILD_STABLE 4 412#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 413 414/* Release-Specific Flags */ 415#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with 416 PNG_LIBPNG_BUILD_STABLE only */ 417#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with 418 PNG_LIBPNG_BUILD_SPECIAL */ 419#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with 420 PNG_LIBPNG_BUILD_PRIVATE */ 421 422#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE 423 424/* Careful here. At one time, Guy wanted to use 082, but that would be octal. 425 * We must not include leading zeros. 426 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only 427 * version 1.0.0 was mis-numbered 100 instead of 10000). From 428 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release 429 */ 430#define PNG_LIBPNG_VER 10512 /* 1.5.12 */ 431 432/* Library configuration: these options cannot be changed after 433 * the library has been built. 434 */ 435#ifndef PNGLCONF_H 436 /* If pnglibconf.h is missing, you can 437 * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h 438 */ 439# include "pnglibconf.h" 440#endif 441 442#ifndef PNG_VERSION_INFO_ONLY 443# ifndef PNG_BUILDING_SYMBOL_TABLE 444 /* 445 * Standard header files (not needed for the version info or while 446 * building symbol table -- see scripts/pnglibconf.dfa) 447 */ 448# ifdef PNG_SETJMP_SUPPORTED 449# include <setjmp.h> 450# endif 451 452 /* Need the time information for converting tIME chunks, it 453 * defines struct tm: 454 */ 455# ifdef PNG_CONVERT_tIME_SUPPORTED 456 /* "time.h" functions are not supported on all operating systems */ 457# include <time.h> 458# endif 459# endif 460 461/* Machine specific configuration. */ 462# include "pngconf.h" 463#endif 464 465/* 466 * Added at libpng-1.2.8 467 * 468 * Ref MSDN: Private as priority over Special 469 * VS_FF_PRIVATEBUILD File *was not* built using standard release 470 * procedures. If this value is given, the StringFileInfo block must 471 * contain a PrivateBuild string. 472 * 473 * VS_FF_SPECIALBUILD File *was* built by the original company using 474 * standard release procedures but is a variation of the standard 475 * file of the same version number. If this value is given, the 476 * StringFileInfo block must contain a SpecialBuild string. 477 */ 478 479#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */ 480# define PNG_LIBPNG_BUILD_TYPE \ 481 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) 482#else 483# ifdef PNG_LIBPNG_SPECIALBUILD 484# define PNG_LIBPNG_BUILD_TYPE \ 485 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) 486# else 487# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) 488# endif 489#endif 490 491#ifndef PNG_VERSION_INFO_ONLY 492 493/* Inhibit C++ name-mangling for libpng functions but not for system calls. */ 494#ifdef __cplusplus 495extern "C" { 496#endif /* __cplusplus */ 497 498/* Version information for C files, stored in png.c. This had better match 499 * the version above. 500 */ 501#define png_libpng_ver png_get_header_ver(NULL) 502 503/* This file is arranged in several sections: 504 * 505 * 1. Any configuration options that can be specified by for the application 506 * code when it is built. (Build time configuration is in pnglibconf.h) 507 * 2. Type definitions (base types are defined in pngconf.h), structure 508 * definitions. 509 * 3. Exported library functions. 510 * 511 * The library source code has additional files (principally pngpriv.h) that 512 * allow configuration of the library. 513 */ 514/* Section 1: run time configuration 515 * See pnglibconf.h for build time configuration 516 * 517 * Run time configuration allows the application to choose between 518 * implementations of certain arithmetic APIs. The default is set 519 * at build time and recorded in pnglibconf.h, but it is safe to 520 * override these (and only these) settings. Note that this won't 521 * change what the library does, only application code, and the 522 * settings can (and probably should) be made on a per-file basis 523 * by setting the #defines before including png.h 524 * 525 * Use macros to read integers from PNG data or use the exported 526 * functions? 527 * PNG_USE_READ_MACROS: use the macros (see below) Note that 528 * the macros evaluate their argument multiple times. 529 * PNG_NO_USE_READ_MACROS: call the relevant library function. 530 * 531 * Use the alternative algorithm for compositing alpha samples that 532 * does not use division? 533 * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' 534 * algorithm. 535 * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. 536 * 537 * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is 538 * false? 539 * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error 540 * APIs to png_warning. 541 * Otherwise the calls are mapped to png_error. 542 */ 543 544/* Section 2: type definitions, including structures and compile time 545 * constants. 546 * See pngconf.h for base types that vary by machine/system 547 */ 548 549/* This triggers a compiler error in png.c, if png.c and png.h 550 * do not agree upon the version number. 551 */ 552typedef char* png_libpng_version_1_5_12; 553 554/* Three color definitions. The order of the red, green, and blue, (and the 555 * exact size) is not important, although the size of the fields need to 556 * be png_byte or png_uint_16 (as defined below). 557 */ 558typedef struct png_color_struct 559{ 560 png_byte red; 561 png_byte green; 562 png_byte blue; 563} png_color; 564typedef png_color FAR * png_colorp; 565typedef PNG_CONST png_color FAR * png_const_colorp; 566typedef png_color FAR * FAR * png_colorpp; 567 568typedef struct png_color_16_struct 569{ 570 png_byte index; /* used for palette files */ 571 png_uint_16 red; /* for use in red green blue files */ 572 png_uint_16 green; 573 png_uint_16 blue; 574 png_uint_16 gray; /* for use in grayscale files */ 575} png_color_16; 576typedef png_color_16 FAR * png_color_16p; 577typedef PNG_CONST png_color_16 FAR * png_const_color_16p; 578typedef png_color_16 FAR * FAR * png_color_16pp; 579 580typedef struct png_color_8_struct 581{ 582 png_byte red; /* for use in red green blue files */ 583 png_byte green; 584 png_byte blue; 585 png_byte gray; /* for use in grayscale files */ 586 png_byte alpha; /* for alpha channel files */ 587} png_color_8; 588typedef png_color_8 FAR * png_color_8p; 589typedef PNG_CONST png_color_8 FAR * png_const_color_8p; 590typedef png_color_8 FAR * FAR * png_color_8pp; 591 592/* 593 * The following two structures are used for the in-core representation 594 * of sPLT chunks. 595 */ 596typedef struct png_sPLT_entry_struct 597{ 598 png_uint_16 red; 599 png_uint_16 green; 600 png_uint_16 blue; 601 png_uint_16 alpha; 602 png_uint_16 frequency; 603} png_sPLT_entry; 604typedef png_sPLT_entry FAR * png_sPLT_entryp; 605typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp; 606typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp; 607 608/* When the depth of the sPLT palette is 8 bits, the color and alpha samples 609 * occupy the LSB of their respective members, and the MSB of each member 610 * is zero-filled. The frequency member always occupies the full 16 bits. 611 */ 612 613typedef struct png_sPLT_struct 614{ 615 png_charp name; /* palette name */ 616 png_byte depth; /* depth of palette samples */ 617 png_sPLT_entryp entries; /* palette entries */ 618 png_int_32 nentries; /* number of palette entries */ 619} png_sPLT_t; 620typedef png_sPLT_t FAR * png_sPLT_tp; 621typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp; 622typedef png_sPLT_t FAR * FAR * png_sPLT_tpp; 623 624#ifdef PNG_TEXT_SUPPORTED 625/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, 626 * and whether that contents is compressed or not. The "key" field 627 * points to a regular zero-terminated C string. The "text" fields can be a 628 * regular C string, an empty string, or a NULL pointer. 629 * However, the structure returned by png_get_text() will always contain 630 * the "text" field as a regular zero-terminated C string (possibly 631 * empty), never a NULL pointer, so it can be safely used in printf() and 632 * other string-handling functions. Note that the "itxt_length", "lang", and 633 * "lang_key" members of the structure only exist when the library is built 634 * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by 635 * default without iTXt support. Also note that when iTXt *is* supported, 636 * the "lang" and "lang_key" fields contain NULL pointers when the 637 * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or 638 * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the 639 * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag" 640 * which is always 0 or 1, or its "compression method" which is always 0. 641 */ 642typedef struct png_text_struct 643{ 644 int compression; /* compression value: 645 -1: tEXt, none 646 0: zTXt, deflate 647 1: iTXt, none 648 2: iTXt, deflate */ 649 png_charp key; /* keyword, 1-79 character description of "text" */ 650 png_charp text; /* comment, may be an empty string (ie "") 651 or a NULL pointer */ 652 png_size_t text_length; /* length of the text string */ 653 png_size_t itxt_length; /* length of the itxt string */ 654 png_charp lang; /* language code, 0-79 characters 655 or a NULL pointer */ 656 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more 657 chars or a NULL pointer */ 658} png_text; 659typedef png_text FAR * png_textp; 660typedef PNG_CONST png_text FAR * png_const_textp; 661typedef png_text FAR * FAR * png_textpp; 662#endif 663 664/* Supported compression types for text in PNG files (tEXt, and zTXt). 665 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ 666#define PNG_TEXT_COMPRESSION_NONE_WR -3 667#define PNG_TEXT_COMPRESSION_zTXt_WR -2 668#define PNG_TEXT_COMPRESSION_NONE -1 669#define PNG_TEXT_COMPRESSION_zTXt 0 670#define PNG_ITXT_COMPRESSION_NONE 1 671#define PNG_ITXT_COMPRESSION_zTXt 2 672#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ 673 674/* png_time is a way to hold the time in an machine independent way. 675 * Two conversions are provided, both from time_t and struct tm. There 676 * is no portable way to convert to either of these structures, as far 677 * as I know. If you know of a portable way, send it to me. As a side 678 * note - PNG has always been Year 2000 compliant! 679 */ 680typedef struct png_time_struct 681{ 682 png_uint_16 year; /* full year, as in, 1995 */ 683 png_byte month; /* month of year, 1 - 12 */ 684 png_byte day; /* day of month, 1 - 31 */ 685 png_byte hour; /* hour of day, 0 - 23 */ 686 png_byte minute; /* minute of hour, 0 - 59 */ 687 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ 688} png_time; 689typedef png_time FAR * png_timep; 690typedef PNG_CONST png_time FAR * png_const_timep; 691typedef png_time FAR * FAR * png_timepp; 692 693#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \ 694 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED) 695/* png_unknown_chunk is a structure to hold queued chunks for which there is 696 * no specific support. The idea is that we can use this to queue 697 * up private chunks for output even though the library doesn't actually 698 * know about their semantics. 699 */ 700typedef struct png_unknown_chunk_t 701{ 702 png_byte name[5]; 703 png_byte *data; 704 png_size_t size; 705 706 /* libpng-using applications should NOT directly modify this byte. */ 707 png_byte location; /* mode of operation at read time */ 708} 709 710 711png_unknown_chunk; 712typedef png_unknown_chunk FAR * png_unknown_chunkp; 713typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp; 714typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp; 715#endif 716 717/* Values for the unknown chunk location byte */ 718 719#define PNG_HAVE_IHDR 0x01 720#define PNG_HAVE_PLTE 0x02 721#define PNG_AFTER_IDAT 0x08 722 723/* The complete definition of png_info has, as of libpng-1.5.0, 724 * been moved into a separate header file that is not accessible to 725 * applications. Read libpng-manual.txt or libpng.3 for more info. 726 */ 727typedef struct png_info_def png_info; 728typedef png_info FAR * png_infop; 729typedef PNG_CONST png_info FAR * png_const_infop; 730typedef png_info FAR * FAR * png_infopp; 731 732/* Maximum positive integer used in PNG is (2^31)-1 */ 733#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) 734#define PNG_UINT_32_MAX ((png_uint_32)(-1)) 735#define PNG_SIZE_MAX ((png_size_t)(-1)) 736 737/* These are constants for fixed point values encoded in the 738 * PNG specification manner (x100000) 739 */ 740#define PNG_FP_1 100000 741#define PNG_FP_HALF 50000 742#define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) 743#define PNG_FP_MIN (-PNG_FP_MAX) 744 745/* These describe the color_type field in png_info. */ 746/* color type masks */ 747#define PNG_COLOR_MASK_PALETTE 1 748#define PNG_COLOR_MASK_COLOR 2 749#define PNG_COLOR_MASK_ALPHA 4 750 751/* color types. Note that not all combinations are legal */ 752#define PNG_COLOR_TYPE_GRAY 0 753#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) 754#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) 755#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) 756#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) 757/* aliases */ 758#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA 759#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA 760 761/* This is for compression type. PNG 1.0-1.2 only define the single type. */ 762#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ 763#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE 764 765/* This is for filter type. PNG 1.0-1.2 only define the single type. */ 766#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ 767#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ 768#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE 769 770/* These are for the interlacing type. These values should NOT be changed. */ 771#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ 772#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ 773#define PNG_INTERLACE_LAST 2 /* Not a valid value */ 774 775/* These are for the oFFs chunk. These values should NOT be changed. */ 776#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ 777#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ 778#define PNG_OFFSET_LAST 2 /* Not a valid value */ 779 780/* These are for the pCAL chunk. These values should NOT be changed. */ 781#define PNG_EQUATION_LINEAR 0 /* Linear transformation */ 782#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ 783#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ 784#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ 785#define PNG_EQUATION_LAST 4 /* Not a valid value */ 786 787/* These are for the sCAL chunk. These values should NOT be changed. */ 788#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ 789#define PNG_SCALE_METER 1 /* meters per pixel */ 790#define PNG_SCALE_RADIAN 2 /* radians per pixel */ 791#define PNG_SCALE_LAST 3 /* Not a valid value */ 792 793/* These are for the pHYs chunk. These values should NOT be changed. */ 794#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ 795#define PNG_RESOLUTION_METER 1 /* pixels/meter */ 796#define PNG_RESOLUTION_LAST 2 /* Not a valid value */ 797 798/* These are for the sRGB chunk. These values should NOT be changed. */ 799#define PNG_sRGB_INTENT_PERCEPTUAL 0 800#define PNG_sRGB_INTENT_RELATIVE 1 801#define PNG_sRGB_INTENT_SATURATION 2 802#define PNG_sRGB_INTENT_ABSOLUTE 3 803#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ 804 805/* This is for text chunks */ 806#define PNG_KEYWORD_MAX_LENGTH 79 807 808/* Maximum number of entries in PLTE/sPLT/tRNS arrays */ 809#define PNG_MAX_PALETTE_LENGTH 256 810 811/* These determine if an ancillary chunk's data has been successfully read 812 * from the PNG header, or if the application has filled in the corresponding 813 * data in the info_struct to be written into the output file. The values 814 * of the PNG_INFO_<chunk> defines should NOT be changed. 815 */ 816#define PNG_INFO_gAMA 0x0001 817#define PNG_INFO_sBIT 0x0002 818#define PNG_INFO_cHRM 0x0004 819#define PNG_INFO_PLTE 0x0008 820#define PNG_INFO_tRNS 0x0010 821#define PNG_INFO_bKGD 0x0020 822#define PNG_INFO_hIST 0x0040 823#define PNG_INFO_pHYs 0x0080 824#define PNG_INFO_oFFs 0x0100 825#define PNG_INFO_tIME 0x0200 826#define PNG_INFO_pCAL 0x0400 827#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */ 828#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */ 829#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */ 830#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */ 831#define PNG_INFO_IDAT 0x8000 /* ESR, 1.0.6 */ 832 833/* This is used for the transformation routines, as some of them 834 * change these values for the row. It also should enable using 835 * the routines for other purposes. 836 */ 837typedef struct png_row_info_struct 838{ 839 png_uint_32 width; /* width of row */ 840 png_size_t rowbytes; /* number of bytes in row */ 841 png_byte color_type; /* color type of row */ 842 png_byte bit_depth; /* bit depth of row */ 843 png_byte channels; /* number of channels (1, 2, 3, or 4) */ 844 png_byte pixel_depth; /* bits per pixel (depth * channels) */ 845} png_row_info; 846 847typedef png_row_info FAR * png_row_infop; 848typedef png_row_info FAR * FAR * png_row_infopp; 849 850/* The complete definition of png_struct has, as of libpng-1.5.0, 851 * been moved into a separate header file that is not accessible to 852 * applications. Read libpng-manual.txt or libpng.3 for more info. 853 */ 854typedef struct png_struct_def png_struct; 855typedef PNG_CONST png_struct FAR * png_const_structp; 856typedef png_struct FAR * png_structp; 857 858/* These are the function types for the I/O functions and for the functions 859 * that allow the user to override the default I/O functions with his or her 860 * own. The png_error_ptr type should match that of user-supplied warning 861 * and error functions, while the png_rw_ptr type should match that of the 862 * user read/write data functions. Note that the 'write' function must not 863 * modify the buffer it is passed. The 'read' function, on the other hand, is 864 * expected to return the read data in the buffer. 865 */ 866typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); 867typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t)); 868typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); 869typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, 870 int)); 871typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, 872 int)); 873 874#ifdef PNG_PROGRESSIVE_READ_SUPPORTED 875typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); 876typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); 877 878/* The following callback receives png_uint_32 row_number, int pass for the 879 * png_bytep data of the row. When transforming an interlaced image the 880 * row number is the row number within the sub-image of the interlace pass, so 881 * the value will increase to the height of the sub-image (not the full image) 882 * then reset to 0 for the next pass. 883 * 884 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to 885 * find the output pixel (x,y) given an interlaced sub-image pixel 886 * (row,col,pass). (See below for these macros.) 887 */ 888typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, 889 png_uint_32, int)); 890#endif 891 892#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ 893 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) 894typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, 895 png_bytep)); 896#endif 897 898#ifdef PNG_USER_CHUNKS_SUPPORTED 899typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, 900 png_unknown_chunkp)); 901#endif 902#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED 903typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); 904#endif 905 906#ifdef PNG_SETJMP_SUPPORTED 907/* This must match the function definition in <setjmp.h>, and the application 908 * must include this before png.h to obtain the definition of jmp_buf. The 909 * function is required to be PNG_NORETURN, but this is not checked. If the 910 * function does return the application will crash via an abort() or similar 911 * system level call. 912 * 913 * If you get a warning here while building the library you may need to make 914 * changes to ensure that pnglibconf.h records the calling convention used by 915 * your compiler. This may be very difficult - try using a different compiler 916 * to build the library! 917 */ 918PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); 919#endif 920 921/* Transform masks for the high-level interface */ 922#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ 923#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ 924#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ 925#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ 926#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ 927#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ 928#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ 929#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ 930#define PNG_TRANSFORM_BGR 0x0080 /* read and write */ 931#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ 932#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ 933#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ 934#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ 935/* Added to libpng-1.2.34 */ 936#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER 937#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ 938/* Added to libpng-1.4.0 */ 939#define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ 940/* Added to libpng-1.5.4 */ 941#define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ 942#define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ 943 944/* Flags for MNG supported features */ 945#define PNG_FLAG_MNG_EMPTY_PLTE 0x01 946#define PNG_FLAG_MNG_FILTER_64 0x04 947#define PNG_ALL_MNG_FEATURES 0x05 948 949/* NOTE: prior to 1.5 these functions had no 'API' style declaration, 950 * this allowed the zlib default functions to be used on Windows 951 * platforms. In 1.5 the zlib default malloc (which just calls malloc and 952 * ignores the first argument) should be completely compatible with the 953 * following. 954 */ 955typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, 956 png_alloc_size_t)); 957typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); 958 959typedef png_struct FAR * FAR * png_structpp; 960 961/* Section 3: exported functions 962 * Here are the function definitions most commonly used. This is not 963 * the place to find out how to use libpng. See libpng-manual.txt for the 964 * full explanation, see example.c for the summary. This just provides 965 * a simple one line description of the use of each function. 966 * 967 * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in 968 * pngconf.h and in the *.dfn files in the scripts directory. 969 * 970 * PNG_EXPORT(ordinal, type, name, (args)); 971 * 972 * ordinal: ordinal that is used while building 973 * *.def files. The ordinal value is only 974 * relevant when preprocessing png.h with 975 * the *.dfn files for building symbol table 976 * entries, and are removed by pngconf.h. 977 * type: return type of the function 978 * name: function name 979 * args: function arguments, with types 980 * 981 * When we wish to append attributes to a function prototype we use 982 * the PNG_EXPORTA() macro instead. 983 * 984 * PNG_EXPORTA(ordinal, type, name, (args), attributes); 985 * 986 * ordinal, type, name, and args: same as in PNG_EXPORT(). 987 * attributes: function attributes 988 */ 989 990/* Returns the version number of the library */ 991PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); 992 993/* Tell lib we have already handled the first <num_bytes> magic bytes. 994 * Handling more than 8 bytes from the beginning of the file is an error. 995 */ 996PNG_EXPORT(2, void, png_set_sig_bytes, (png_structp png_ptr, int num_bytes)); 997 998/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a 999 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG 1000 * signature, and non-zero otherwise. Having num_to_check == 0 or 1001 * start > 7 will always fail (ie return non-zero). 1002 */ 1003PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start, 1004 png_size_t num_to_check)); 1005 1006/* Simple signature checking function. This is the same as calling 1007 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). 1008 */ 1009#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) 1010 1011/* Allocate and initialize png_ptr struct for reading, and any other memory. */ 1012PNG_EXPORTA(4, png_structp, png_create_read_struct, 1013 (png_const_charp user_png_ver, png_voidp error_ptr, 1014 png_error_ptr error_fn, png_error_ptr warn_fn), 1015 PNG_ALLOCATED); 1016 1017/* Allocate and initialize png_ptr struct for writing, and any other memory */ 1018PNG_EXPORTA(5, png_structp, png_create_write_struct, 1019 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1020 png_error_ptr warn_fn), 1021 PNG_ALLOCATED); 1022 1023PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size, 1024 (png_const_structp png_ptr)); 1025 1026PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structp png_ptr, 1027 png_size_t size)); 1028 1029/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp 1030 * match up. 1031 */ 1032#ifdef PNG_SETJMP_SUPPORTED 1033/* This function returns the jmp_buf built in to *png_ptr. It must be 1034 * supplied with an appropriate 'longjmp' function to use on that jmp_buf 1035 * unless the default error function is overridden in which case NULL is 1036 * acceptable. The size of the jmp_buf is checked against the actual size 1037 * allocated by the library - the call will return NULL on a mismatch 1038 * indicating an ABI mismatch. 1039 */ 1040PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structp png_ptr, 1041 png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); 1042# define png_jmpbuf(png_ptr) \ 1043 (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf))) 1044#else 1045# define png_jmpbuf(png_ptr) \ 1046 (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) 1047#endif 1048/* This function should be used by libpng applications in place of 1049 * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it 1050 * will use it; otherwise it will call PNG_ABORT(). This function was 1051 * added in libpng-1.5.0. 1052 */ 1053PNG_EXPORTA(9, void, png_longjmp, (png_structp png_ptr, int val), 1054 PNG_NORETURN); 1055 1056#ifdef PNG_READ_SUPPORTED 1057/* Reset the compression stream */ 1058PNG_EXPORT(10, int, png_reset_zstream, (png_structp png_ptr)); 1059#endif 1060 1061/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ 1062#ifdef PNG_USER_MEM_SUPPORTED 1063PNG_EXPORTA(11, png_structp, png_create_read_struct_2, 1064 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1065 png_error_ptr warn_fn, 1066 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), 1067 PNG_ALLOCATED); 1068PNG_EXPORTA(12, png_structp, png_create_write_struct_2, 1069 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1070 png_error_ptr warn_fn, 1071 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), 1072 PNG_ALLOCATED); 1073#endif 1074 1075/* Write the PNG file signature. */ 1076PNG_EXPORT(13, void, png_write_sig, (png_structp png_ptr)); 1077 1078/* Write a PNG chunk - size, type, (optional) data, CRC. */ 1079PNG_EXPORT(14, void, png_write_chunk, (png_structp png_ptr, png_const_bytep 1080 chunk_name, png_const_bytep data, png_size_t length)); 1081 1082/* Write the start of a PNG chunk - length and chunk name. */ 1083PNG_EXPORT(15, void, png_write_chunk_start, (png_structp png_ptr, 1084 png_const_bytep chunk_name, png_uint_32 length)); 1085 1086/* Write the data of a PNG chunk started with png_write_chunk_start(). */ 1087PNG_EXPORT(16, void, png_write_chunk_data, (png_structp png_ptr, 1088 png_const_bytep data, png_size_t length)); 1089 1090/* Finish a chunk started with png_write_chunk_start() (includes CRC). */ 1091PNG_EXPORT(17, void, png_write_chunk_end, (png_structp png_ptr)); 1092 1093/* Allocate and initialize the info structure */ 1094PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_structp png_ptr), 1095 PNG_ALLOCATED); 1096 1097PNG_EXPORT(19, void, png_info_init_3, (png_infopp info_ptr, 1098 png_size_t png_info_struct_size)); 1099 1100/* Writes all the PNG information before the image. */ 1101PNG_EXPORT(20, void, png_write_info_before_PLTE, 1102 (png_structp png_ptr, png_infop info_ptr)); 1103PNG_EXPORT(21, void, png_write_info, 1104 (png_structp png_ptr, png_infop info_ptr)); 1105 1106#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1107/* Read the information before the actual image data. */ 1108PNG_EXPORT(22, void, png_read_info, 1109 (png_structp png_ptr, png_infop info_ptr)); 1110#endif 1111 1112#ifdef PNG_TIME_RFC1123_SUPPORTED 1113PNG_EXPORT(23, png_const_charp, png_convert_to_rfc1123, 1114 (png_structp png_ptr, 1115 png_const_timep ptime)); 1116#endif 1117 1118#ifdef PNG_CONVERT_tIME_SUPPORTED 1119/* Convert from a struct tm to png_time */ 1120PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, 1121 PNG_CONST struct tm FAR * ttime)); 1122 1123/* Convert from time_t to png_time. Uses gmtime() */ 1124PNG_EXPORT(25, void, png_convert_from_time_t, 1125 (png_timep ptime, time_t ttime)); 1126#endif /* PNG_CONVERT_tIME_SUPPORTED */ 1127 1128#ifdef PNG_READ_EXPAND_SUPPORTED 1129/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ 1130PNG_EXPORT(26, void, png_set_expand, (png_structp png_ptr)); 1131PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structp png_ptr)); 1132PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structp png_ptr)); 1133PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr)); 1134#endif 1135 1136#ifdef PNG_READ_EXPAND_16_SUPPORTED 1137/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion 1138 * of a tRNS chunk if present. 1139 */ 1140PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr)); 1141#endif 1142 1143#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) 1144/* Use blue, green, red order for pixels. */ 1145PNG_EXPORT(30, void, png_set_bgr, (png_structp png_ptr)); 1146#endif 1147 1148#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED 1149/* Expand the grayscale to 24-bit RGB if necessary. */ 1150PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr)); 1151#endif 1152 1153#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED 1154/* Reduce RGB to grayscale. */ 1155#define PNG_ERROR_ACTION_NONE 1 1156#define PNG_ERROR_ACTION_WARN 2 1157#define PNG_ERROR_ACTION_ERROR 3 1158#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ 1159 1160PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr, 1161 int error_action, double red, double green)); 1162PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr, 1163 int error_action, png_fixed_point red, png_fixed_point green)); 1164 1165PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp 1166 png_ptr)); 1167#endif 1168 1169#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED 1170PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, 1171 png_colorp palette)); 1172#endif 1173 1174#ifdef PNG_READ_ALPHA_MODE_SUPPORTED 1175/* How the alpha channel is interpreted - this affects how the color channels of 1176 * a PNG file are returned when an alpha channel, or tRNS chunk in a palette 1177 * file, is present. 1178 * 1179 * This has no effect on the way pixels are written into a PNG output 1180 * datastream. The color samples in a PNG datastream are never premultiplied 1181 * with the alpha samples. 1182 * 1183 * The default is to return data according to the PNG specification: the alpha 1184 * channel is a linear measure of the contribution of the pixel to the 1185 * corresponding composited pixel. The gamma encoded color channels must be 1186 * scaled according to the contribution and to do this it is necessary to undo 1187 * the encoding, scale the color values, perform the composition and reencode 1188 * the values. This is the 'PNG' mode. 1189 * 1190 * The alternative is to 'associate' the alpha with the color information by 1191 * storing color channel values that have been scaled by the alpha. The 1192 * advantage is that the color channels can be resampled (the image can be 1193 * scaled) in this form. The disadvantage is that normal practice is to store 1194 * linear, not (gamma) encoded, values and this requires 16-bit channels for 1195 * still images rather than the 8-bit channels that are just about sufficient if 1196 * gamma encoding is used. In addition all non-transparent pixel values, 1197 * including completely opaque ones, must be gamma encoded to produce the final 1198 * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the 1199 * latter being the two common names for associated alpha color channels.) 1200 * 1201 * Since it is not necessary to perform arithmetic on opaque color values so 1202 * long as they are not to be resampled and are in the final color space it is 1203 * possible to optimize the handling of alpha by storing the opaque pixels in 1204 * the PNG format (adjusted for the output color space) while storing partially 1205 * opaque pixels in the standard, linear, format. The accuracy required for 1206 * standard alpha composition is relatively low, because the pixels are 1207 * isolated, therefore typically the accuracy loss in storing 8-bit linear 1208 * values is acceptable. (This is not true if the alpha channel is used to 1209 * simulate transparency over large areas - use 16 bits or the PNG mode in 1210 * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is 1211 * treated as opaque only if the alpha value is equal to the maximum value. 1212 * 1213 * The final choice is to gamma encode the alpha channel as well. This is 1214 * broken because, in practice, no implementation that uses this choice 1215 * correctly undoes the encoding before handling alpha composition. Use this 1216 * choice only if other serious errors in the software or hardware you use 1217 * mandate it; the typical serious error is for dark halos to appear around 1218 * opaque areas of the composited PNG image because of arithmetic overflow. 1219 * 1220 * The API function png_set_alpha_mode specifies which of these choices to use 1221 * with an enumerated 'mode' value and the gamma of the required output: 1222 */ 1223#define PNG_ALPHA_PNG 0 /* according to the PNG standard */ 1224#define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ 1225#define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ 1226#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ 1227#define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ 1228#define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ 1229 1230PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode, 1231 double output_gamma)); 1232PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr, 1233 int mode, png_fixed_point output_gamma)); 1234#endif 1235 1236#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) 1237/* The output_gamma value is a screen gamma in libpng terminology: it expresses 1238 * how to decode the output values, not how they are encoded. The values used 1239 * correspond to the normal numbers used to describe the overall gamma of a 1240 * computer display system; for example 2.2 for an sRGB conformant system. The 1241 * values are scaled by 100000 in the _fixed version of the API (so 220000 for 1242 * sRGB.) 1243 * 1244 * The inverse of the value is always used to provide a default for the PNG file 1245 * encoding if it has no gAMA chunk and if png_set_gamma() has not been called 1246 * to override the PNG gamma information. 1247 * 1248 * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode 1249 * opaque pixels however pixels with lower alpha values are not encoded, 1250 * regardless of the output gamma setting. 1251 * 1252 * When the standard Porter Duff handling is requested with mode 1 the output 1253 * encoding is set to be linear and the output_gamma value is only relevant 1254 * as a default for input data that has no gamma information. The linear output 1255 * encoding will be overridden if png_set_gamma() is called - the results may be 1256 * highly unexpected! 1257 * 1258 * The following numbers are derived from the sRGB standard and the research 1259 * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of 1260 * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing 1261 * correction required to take account of any differences in the color 1262 * environment of the original scene and the intended display environment; the 1263 * value expresses how to *decode* the image for display, not how the original 1264 * data was *encoded*. 1265 * 1266 * sRGB provides a peg for the PNG standard by defining a viewing environment. 1267 * sRGB itself, and earlier TV standards, actually use a more complex transform 1268 * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is 1269 * limited to simple power laws.) By saying that an image for direct display on 1270 * an sRGB conformant system should be stored with a gAMA chunk value of 45455 1271 * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification 1272 * makes it possible to derive values for other display systems and 1273 * environments. 1274 * 1275 * The Mac value is deduced from the sRGB based on an assumption that the actual 1276 * extra viewing correction used in early Mac display systems was implemented as 1277 * a power 1.45 lookup table. 1278 * 1279 * Any system where a programmable lookup table is used or where the behavior of 1280 * the final display device characteristics can be changed requires system 1281 * specific code to obtain the current characteristic. However this can be 1282 * difficult and most PNG gamma correction only requires an approximate value. 1283 * 1284 * By default, if png_set_alpha_mode() is not called, libpng assumes that all 1285 * values are unencoded, linear, values and that the output device also has a 1286 * linear characteristic. This is only very rarely correct - it is invariably 1287 * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the 1288 * default if you don't know what the right answer is! 1289 * 1290 * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS 1291 * 10.6) which used a correction table to implement a somewhat lower gamma on an 1292 * otherwise sRGB system. 1293 * 1294 * Both these values are reserved (not simple gamma values) in order to allow 1295 * more precise correction internally in the future. 1296 * 1297 * NOTE: the following values can be passed to either the fixed or floating 1298 * point APIs, but the floating point API will also accept floating point 1299 * values. 1300 */ 1301#define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ 1302#define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ 1303#define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ 1304#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ 1305#endif 1306 1307/* The following are examples of calls to png_set_alpha_mode to achieve the 1308 * required overall gamma correction and, where necessary, alpha 1309 * premultiplication. 1310 * 1311 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); 1312 * This is the default libpng handling of the alpha channel - it is not 1313 * pre-multiplied into the color components. In addition the call states 1314 * that the output is for a sRGB system and causes all PNG files without gAMA 1315 * chunks to be assumed to be encoded using sRGB. 1316 * 1317 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); 1318 * In this case the output is assumed to be something like an sRGB conformant 1319 * display preceeded by a power-law lookup table of power 1.45. This is how 1320 * early Mac systems behaved. 1321 * 1322 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); 1323 * This is the classic Jim Blinn approach and will work in academic 1324 * environments where everything is done by the book. It has the shortcoming 1325 * of assuming that input PNG data with no gamma information is linear - this 1326 * is unlikely to be correct unless the PNG files where generated locally. 1327 * Most of the time the output precision will be so low as to show 1328 * significant banding in dark areas of the image. 1329 * 1330 * png_set_expand_16(pp); 1331 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); 1332 * This is a somewhat more realistic Jim Blinn inspired approach. PNG files 1333 * are assumed to have the sRGB encoding if not marked with a gamma value and 1334 * the output is always 16 bits per component. This permits accurate scaling 1335 * and processing of the data. If you know that your input PNG files were 1336 * generated locally you might need to replace PNG_DEFAULT_sRGB with the 1337 * correct value for your system. 1338 * 1339 * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); 1340 * If you just need to composite the PNG image onto an existing background 1341 * and if you control the code that does this you can use the optimization 1342 * setting. In this case you just copy completely opaque pixels to the 1343 * output. For pixels that are not completely transparent (you just skip 1344 * those) you do the composition math using png_composite or png_composite_16 1345 * below then encode the resultant 8-bit or 16-bit values to match the output 1346 * encoding. 1347 * 1348 * Other cases 1349 * If neither the PNG nor the standard linear encoding work for you because 1350 * of the software or hardware you use then you have a big problem. The PNG 1351 * case will probably result in halos around the image. The linear encoding 1352 * will probably result in a washed out, too bright, image (it's actually too 1353 * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably 1354 * substantially reduce the halos. Alternatively try: 1355 * 1356 * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); 1357 * This option will also reduce the halos, but there will be slight dark 1358 * halos round the opaque parts of the image where the background is light. 1359 * In the OPTIMIZED mode the halos will be light halos where the background 1360 * is dark. Take your pick - the halos are unavoidable unless you can get 1361 * your hardware/software fixed! (The OPTIMIZED approach is slightly 1362 * faster.) 1363 * 1364 * When the default gamma of PNG files doesn't match the output gamma. 1365 * If you have PNG files with no gamma information png_set_alpha_mode allows 1366 * you to provide a default gamma, but it also sets the ouput gamma to the 1367 * matching value. If you know your PNG files have a gamma that doesn't 1368 * match the output you can take advantage of the fact that 1369 * png_set_alpha_mode always sets the output gamma but only sets the PNG 1370 * default if it is not already set: 1371 * 1372 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); 1373 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); 1374 * The first call sets both the default and the output gamma values, the 1375 * second call overrides the output gamma without changing the default. This 1376 * is easier than achieving the same effect with png_set_gamma. You must use 1377 * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will 1378 * fire if more than one call to png_set_alpha_mode and png_set_background is 1379 * made in the same read operation, however multiple calls with PNG_ALPHA_PNG 1380 * are ignored. 1381 */ 1382 1383#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED 1384PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr)); 1385#endif 1386 1387#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ 1388 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) 1389PNG_EXPORT(37, void, png_set_swap_alpha, (png_structp png_ptr)); 1390#endif 1391 1392#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ 1393 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) 1394PNG_EXPORT(38, void, png_set_invert_alpha, (png_structp png_ptr)); 1395#endif 1396 1397#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) 1398/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */ 1399PNG_EXPORT(39, void, png_set_filler, (png_structp png_ptr, png_uint_32 filler, 1400 int flags)); 1401/* The values of the PNG_FILLER_ defines should NOT be changed */ 1402# define PNG_FILLER_BEFORE 0 1403# define PNG_FILLER_AFTER 1 1404/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ 1405PNG_EXPORT(40, void, png_set_add_alpha, 1406 (png_structp png_ptr, png_uint_32 filler, 1407 int flags)); 1408#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */ 1409 1410#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) 1411/* Swap bytes in 16-bit depth files. */ 1412PNG_EXPORT(41, void, png_set_swap, (png_structp png_ptr)); 1413#endif 1414 1415#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) 1416/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ 1417PNG_EXPORT(42, void, png_set_packing, (png_structp png_ptr)); 1418#endif 1419 1420#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ 1421 defined(PNG_WRITE_PACKSWAP_SUPPORTED) 1422/* Swap packing order of pixels in bytes. */ 1423PNG_EXPORT(43, void, png_set_packswap, (png_structp png_ptr)); 1424#endif 1425 1426#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) 1427/* Converts files to legal bit depths. */ 1428PNG_EXPORT(44, void, png_set_shift, (png_structp png_ptr, png_const_color_8p 1429 true_bits)); 1430#endif 1431 1432#if defined(PNG_READ_INTERLACING_SUPPORTED) || \ 1433 defined(PNG_WRITE_INTERLACING_SUPPORTED) 1434/* Have the code handle the interlacing. Returns the number of passes. 1435 * MUST be called before png_read_update_info or png_start_read_image, 1436 * otherwise it will not have the desired effect. Note that it is still 1437 * necessary to call png_read_row or png_read_rows png_get_image_height 1438 * times for each pass. 1439*/ 1440PNG_EXPORT(45, int, png_set_interlace_handling, (png_structp png_ptr)); 1441#endif 1442 1443#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) 1444/* Invert monochrome files */ 1445PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr)); 1446#endif 1447 1448#ifdef PNG_READ_BACKGROUND_SUPPORTED 1449/* Handle alpha and tRNS by replacing with a background color. Prior to 1450 * libpng-1.5.4 this API must not be called before the PNG file header has been 1451 * read. Doing so will result in unexpected behavior and possible warnings or 1452 * errors if the PNG file contains a bKGD chunk. 1453 */ 1454PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr, 1455 png_const_color_16p background_color, int background_gamma_code, 1456 int need_expand, double background_gamma)); 1457PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr, 1458 png_const_color_16p background_color, int background_gamma_code, 1459 int need_expand, png_fixed_point background_gamma)); 1460#endif 1461#ifdef PNG_READ_BACKGROUND_SUPPORTED 1462# define PNG_BACKGROUND_GAMMA_UNKNOWN 0 1463# define PNG_BACKGROUND_GAMMA_SCREEN 1 1464# define PNG_BACKGROUND_GAMMA_FILE 2 1465# define PNG_BACKGROUND_GAMMA_UNIQUE 3 1466#endif 1467 1468#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED 1469/* Scale a 16-bit depth file down to 8-bit, accurately. */ 1470PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr)); 1471#endif 1472 1473#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED 1474#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */ 1475/* Strip the second byte of information from a 16-bit depth file. */ 1476PNG_EXPORT(48, void, png_set_strip_16, (png_structp png_ptr)); 1477#endif 1478 1479#ifdef PNG_READ_QUANTIZE_SUPPORTED 1480/* Turn on quantizing, and reduce the palette to the number of colors 1481 * available. 1482 */ 1483PNG_EXPORT(49, void, png_set_quantize, 1484 (png_structp png_ptr, png_colorp palette, 1485 int num_palette, int maximum_colors, png_const_uint_16p histogram, 1486 int full_quantize)); 1487#endif 1488 1489#ifdef PNG_READ_GAMMA_SUPPORTED 1490/* The threshold on gamma processing is configurable but hard-wired into the 1491 * library. The following is the floating point variant. 1492 */ 1493#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) 1494 1495/* Handle gamma correction. Screen_gamma=(display_exponent). 1496 * NOTE: this API simply sets the screen and file gamma values. It will 1497 * therefore override the value for gamma in a PNG file if it is called after 1498 * the file header has been read - use with care - call before reading the PNG 1499 * file for best results! 1500 * 1501 * These routines accept the same gamma values as png_set_alpha_mode (described 1502 * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either 1503 * API (floating point or fixed.) Notice, however, that the 'file_gamma' value 1504 * is the inverse of a 'screen gamma' value. 1505 */ 1506PNG_FP_EXPORT(50, void, png_set_gamma, 1507 (png_structp png_ptr, double screen_gamma, 1508 double override_file_gamma)); 1509PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr, 1510 png_fixed_point screen_gamma, png_fixed_point override_file_gamma)); 1511#endif 1512 1513#ifdef PNG_WRITE_FLUSH_SUPPORTED 1514/* Set how many lines between output flushes - 0 for no flushing */ 1515PNG_EXPORT(51, void, png_set_flush, (png_structp png_ptr, int nrows)); 1516/* Flush the current PNG output buffer */ 1517PNG_EXPORT(52, void, png_write_flush, (png_structp png_ptr)); 1518#endif 1519 1520/* Optional update palette with requested transformations */ 1521PNG_EXPORT(53, void, png_start_read_image, (png_structp png_ptr)); 1522 1523/* Optional call to update the users info structure */ 1524PNG_EXPORT(54, void, png_read_update_info, 1525 (png_structp png_ptr, png_infop info_ptr)); 1526 1527#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1528/* Read one or more rows of image data. */ 1529PNG_EXPORT(55, void, png_read_rows, (png_structp png_ptr, png_bytepp row, 1530 png_bytepp display_row, png_uint_32 num_rows)); 1531#endif 1532 1533#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1534/* Read a row of data. */ 1535PNG_EXPORT(56, void, png_read_row, (png_structp png_ptr, png_bytep row, 1536 png_bytep display_row)); 1537#endif 1538 1539#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1540/* Read the whole image into memory at once. */ 1541PNG_EXPORT(57, void, png_read_image, (png_structp png_ptr, png_bytepp image)); 1542#endif 1543 1544/* Write a row of image data */ 1545PNG_EXPORT(58, void, png_write_row, 1546 (png_structp png_ptr, png_const_bytep row)); 1547 1548/* Write a few rows of image data: (*row) is not written; however, the type 1549 * is declared as writeable to maintain compatibility with previous versions 1550 * of libpng and to allow the 'display_row' array from read_rows to be passed 1551 * unchanged to write_rows. 1552 */ 1553PNG_EXPORT(59, void, png_write_rows, (png_structp png_ptr, png_bytepp row, 1554 png_uint_32 num_rows)); 1555 1556/* Write the image data */ 1557PNG_EXPORT(60, void, png_write_image, 1558 (png_structp png_ptr, png_bytepp image)); 1559 1560/* Write the end of the PNG file. */ 1561PNG_EXPORT(61, void, png_write_end, 1562 (png_structp png_ptr, png_infop info_ptr)); 1563 1564#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1565/* Read the end of the PNG file. */ 1566PNG_EXPORT(62, void, png_read_end, (png_structp png_ptr, png_infop info_ptr)); 1567#endif 1568 1569/* Free any memory associated with the png_info_struct */ 1570PNG_EXPORT(63, void, png_destroy_info_struct, (png_structp png_ptr, 1571 png_infopp info_ptr_ptr)); 1572 1573/* Free any memory associated with the png_struct and the png_info_structs */ 1574PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, 1575 png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); 1576 1577/* Free any memory associated with the png_struct and the png_info_structs */ 1578PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, 1579 png_infopp info_ptr_ptr)); 1580 1581/* Set the libpng method of handling chunk CRC errors */ 1582PNG_EXPORT(66, void, png_set_crc_action, 1583 (png_structp png_ptr, int crit_action, int ancil_action)); 1584 1585/* Values for png_set_crc_action() say how to handle CRC errors in 1586 * ancillary and critical chunks, and whether to use the data contained 1587 * therein. Note that it is impossible to "discard" data in a critical 1588 * chunk. For versions prior to 0.90, the action was always error/quit, 1589 * whereas in version 0.90 and later, the action for CRC errors in ancillary 1590 * chunks is warn/discard. These values should NOT be changed. 1591 * 1592 * value action:critical action:ancillary 1593 */ 1594#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ 1595#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ 1596#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ 1597#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ 1598#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ 1599#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ 1600 1601/* These functions give the user control over the scan-line filtering in 1602 * libpng and the compression methods used by zlib. These functions are 1603 * mainly useful for testing, as the defaults should work with most users. 1604 * Those users who are tight on memory or want faster performance at the 1605 * expense of compression can modify them. See the compression library 1606 * header file (zlib.h) for an explination of the compression functions. 1607 */ 1608 1609/* Set the filtering method(s) used by libpng. Currently, the only valid 1610 * value for "method" is 0. 1611 */ 1612PNG_EXPORT(67, void, png_set_filter, 1613 (png_structp png_ptr, int method, int filters)); 1614 1615/* Flags for png_set_filter() to say which filters to use. The flags 1616 * are chosen so that they don't conflict with real filter types 1617 * below, in case they are supplied instead of the #defined constants. 1618 * These values should NOT be changed. 1619 */ 1620#define PNG_NO_FILTERS 0x00 1621#define PNG_FILTER_NONE 0x08 1622#define PNG_FILTER_SUB 0x10 1623#define PNG_FILTER_UP 0x20 1624#define PNG_FILTER_AVG 0x40 1625#define PNG_FILTER_PAETH 0x80 1626#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \ 1627 PNG_FILTER_AVG | PNG_FILTER_PAETH) 1628 1629/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. 1630 * These defines should NOT be changed. 1631 */ 1632#define PNG_FILTER_VALUE_NONE 0 1633#define PNG_FILTER_VALUE_SUB 1 1634#define PNG_FILTER_VALUE_UP 2 1635#define PNG_FILTER_VALUE_AVG 3 1636#define PNG_FILTER_VALUE_PAETH 4 1637#define PNG_FILTER_VALUE_LAST 5 1638 1639#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */ 1640/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_ 1641 * defines, either the default (minimum-sum-of-absolute-differences), or 1642 * the experimental method (weighted-minimum-sum-of-absolute-differences). 1643 * 1644 * Weights are factors >= 1.0, indicating how important it is to keep the 1645 * filter type consistent between rows. Larger numbers mean the current 1646 * filter is that many times as likely to be the same as the "num_weights" 1647 * previous filters. This is cumulative for each previous row with a weight. 1648 * There needs to be "num_weights" values in "filter_weights", or it can be 1649 * NULL if the weights aren't being specified. Weights have no influence on 1650 * the selection of the first row filter. Well chosen weights can (in theory) 1651 * improve the compression for a given image. 1652 * 1653 * Costs are factors >= 1.0 indicating the relative decoding costs of a 1654 * filter type. Higher costs indicate more decoding expense, and are 1655 * therefore less likely to be selected over a filter with lower computational 1656 * costs. There needs to be a value in "filter_costs" for each valid filter 1657 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't 1658 * setting the costs. Costs try to improve the speed of decompression without 1659 * unduly increasing the compressed image size. 1660 * 1661 * A negative weight or cost indicates the default value is to be used, and 1662 * values in the range [0.0, 1.0) indicate the value is to remain unchanged. 1663 * The default values for both weights and costs are currently 1.0, but may 1664 * change if good general weighting/cost heuristics can be found. If both 1665 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method 1666 * to the UNWEIGHTED method, but with added encoding time/computation. 1667 */ 1668PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr, 1669 int heuristic_method, int num_weights, png_const_doublep filter_weights, 1670 png_const_doublep filter_costs)); 1671PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, 1672 (png_structp png_ptr, 1673 int heuristic_method, int num_weights, png_const_fixed_point_p 1674 filter_weights, png_const_fixed_point_p filter_costs)); 1675#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ 1676 1677/* Heuristic used for row filter selection. These defines should NOT be 1678 * changed. 1679 */ 1680#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ 1681#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ 1682#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ 1683#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ 1684 1685#ifdef PNG_WRITE_SUPPORTED 1686/* Set the library compression level. Currently, valid values range from 1687 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 1688 * (0 - no compression, 9 - "maximal" compression). Note that tests have 1689 * shown that zlib compression levels 3-6 usually perform as well as level 9 1690 * for PNG images, and do considerably fewer caclulations. In the future, 1691 * these values may not correspond directly to the zlib compression levels. 1692 */ 1693PNG_EXPORT(69, void, png_set_compression_level, 1694 (png_structp png_ptr, int level)); 1695 1696PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr, 1697 int mem_level)); 1698 1699PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr, 1700 int strategy)); 1701 1702/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a 1703 * smaller value of window_bits if it can do so safely. 1704 */ 1705PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr, 1706 int window_bits)); 1707 1708PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr, 1709 int method)); 1710#endif 1711 1712#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED 1713/* Also set zlib parameters for compressing non-IDAT chunks */ 1714PNG_EXPORT(222, void, png_set_text_compression_level, 1715 (png_structp png_ptr, int level)); 1716 1717PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr, 1718 int mem_level)); 1719 1720PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr, 1721 int strategy)); 1722 1723/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a 1724 * smaller value of window_bits if it can do so safely. 1725 */ 1726PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp 1727 png_ptr, int window_bits)); 1728 1729PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr, 1730 int method)); 1731#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */ 1732 1733/* These next functions are called for input/output, memory, and error 1734 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, 1735 * and call standard C I/O routines such as fread(), fwrite(), and 1736 * fprintf(). These functions can be made to use other I/O routines 1737 * at run time for those applications that need to handle I/O in a 1738 * different manner by calling png_set_???_fn(). See libpng-manual.txt for 1739 * more information. 1740 */ 1741 1742#ifdef PNG_STDIO_SUPPORTED 1743/* Initialize the input/output for the PNG file to the default functions. */ 1744PNG_EXPORT(74, void, png_init_io, (png_structp png_ptr, png_FILE_p fp)); 1745#endif 1746 1747/* Replace the (error and abort), and warning functions with user 1748 * supplied functions. If no messages are to be printed you must still 1749 * write and use replacement functions. The replacement error_fn should 1750 * still do a longjmp to the last setjmp location if you are using this 1751 * method of error handling. If error_fn or warning_fn is NULL, the 1752 * default function will be used. 1753 */ 1754 1755PNG_EXPORT(75, void, png_set_error_fn, 1756 (png_structp png_ptr, png_voidp error_ptr, 1757 png_error_ptr error_fn, png_error_ptr warning_fn)); 1758 1759/* Return the user pointer associated with the error functions */ 1760PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structp png_ptr)); 1761 1762/* Replace the default data output functions with a user supplied one(s). 1763 * If buffered output is not used, then output_flush_fn can be set to NULL. 1764 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time 1765 * output_flush_fn will be ignored (and thus can be NULL). 1766 * It is probably a mistake to use NULL for output_flush_fn if 1767 * write_data_fn is not also NULL unless you have built libpng with 1768 * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's 1769 * default flush function, which uses the standard *FILE structure, will 1770 * be used. 1771 */ 1772PNG_EXPORT(77, void, png_set_write_fn, (png_structp png_ptr, png_voidp io_ptr, 1773 png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); 1774 1775/* Replace the default data input function with a user supplied one. */ 1776PNG_EXPORT(78, void, png_set_read_fn, (png_structp png_ptr, png_voidp io_ptr, 1777 png_rw_ptr read_data_fn)); 1778 1779/* Return the user pointer associated with the I/O functions */ 1780PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_structp png_ptr)); 1781 1782PNG_EXPORT(80, void, png_set_read_status_fn, (png_structp png_ptr, 1783 png_read_status_ptr read_row_fn)); 1784 1785PNG_EXPORT(81, void, png_set_write_status_fn, (png_structp png_ptr, 1786 png_write_status_ptr write_row_fn)); 1787 1788#ifdef PNG_USER_MEM_SUPPORTED 1789/* Replace the default memory allocation functions with user supplied one(s). */ 1790PNG_EXPORT(82, void, png_set_mem_fn, (png_structp png_ptr, png_voidp mem_ptr, 1791 png_malloc_ptr malloc_fn, png_free_ptr free_fn)); 1792/* Return the user pointer associated with the memory functions */ 1793PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structp png_ptr)); 1794#endif 1795 1796#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED 1797PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structp png_ptr, 1798 png_user_transform_ptr read_user_transform_fn)); 1799#endif 1800 1801#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED 1802PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structp png_ptr, 1803 png_user_transform_ptr write_user_transform_fn)); 1804#endif 1805 1806#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED 1807PNG_EXPORT(86, void, png_set_user_transform_info, (png_structp png_ptr, 1808 png_voidp user_transform_ptr, int user_transform_depth, 1809 int user_transform_channels)); 1810/* Return the user pointer associated with the user transform functions */ 1811PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, 1812 (png_const_structp png_ptr)); 1813#endif 1814 1815#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED 1816/* Return information about the row currently being processed. Note that these 1817 * APIs do not fail but will return unexpected results if called outside a user 1818 * transform callback. Also note that when transforming an interlaced image the 1819 * row number is the row number within the sub-image of the interlace pass, so 1820 * the value will increase to the height of the sub-image (not the full image) 1821 * then reset to 0 for the next pass. 1822 * 1823 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to 1824 * find the output pixel (x,y) given an interlaced sub-image pixel 1825 * (row,col,pass). (See below for these macros.) 1826 */ 1827PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp)); 1828PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp)); 1829#endif 1830 1831#ifdef PNG_USER_CHUNKS_SUPPORTED 1832PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structp png_ptr, 1833 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); 1834PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structp png_ptr)); 1835#endif 1836 1837#ifdef PNG_PROGRESSIVE_READ_SUPPORTED 1838/* Sets the function callbacks for the push reader, and a pointer to a 1839 * user-defined structure available to the callback functions. 1840 */ 1841PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structp png_ptr, 1842 png_voidp progressive_ptr, png_progressive_info_ptr info_fn, 1843 png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); 1844 1845/* Returns the user pointer associated with the push read functions */ 1846PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, (png_const_structp png_ptr)); 1847 1848/* Function to be called when data becomes available */ 1849PNG_EXPORT(92, void, png_process_data, 1850 (png_structp png_ptr, png_infop info_ptr, 1851 png_bytep buffer, png_size_t buffer_size)); 1852 1853/* A function which may be called *only* within png_process_data to stop the 1854 * processing of any more data. The function returns the number of bytes 1855 * remaining, excluding any that libpng has cached internally. A subsequent 1856 * call to png_process_data must supply these bytes again. If the argument 1857 * 'save' is set to true the routine will first save all the pending data and 1858 * will always return 0. 1859 */ 1860PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structp, int save)); 1861 1862/* A function which may be called *only* outside (after) a call to 1863 * png_process_data. It returns the number of bytes of data to skip in the 1864 * input. Normally it will return 0, but if it returns a non-zero value the 1865 * application must skip than number of bytes of input data and pass the 1866 * following data to the next call to png_process_data. 1867 */ 1868PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structp)); 1869 1870#ifdef PNG_READ_INTERLACING_SUPPORTED 1871/* Function that combines rows. 'new_row' is a flag that should come from 1872 * the callback and be non-NULL if anything needs to be done; the library 1873 * stores its own version of the new data internally and ignores the passed 1874 * in value. 1875 */ 1876PNG_EXPORT(93, void, png_progressive_combine_row, (png_structp png_ptr, 1877 png_bytep old_row, png_const_bytep new_row)); 1878#endif /* PNG_READ_INTERLACING_SUPPORTED */ 1879#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ 1880 1881PNG_EXPORTA(94, png_voidp, png_malloc, 1882 (png_structp png_ptr, png_alloc_size_t size), 1883 PNG_ALLOCATED); 1884/* Added at libpng version 1.4.0 */ 1885PNG_EXPORTA(95, png_voidp, png_calloc, 1886 (png_structp png_ptr, png_alloc_size_t size), 1887 PNG_ALLOCATED); 1888 1889/* Added at libpng version 1.2.4 */ 1890PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_structp png_ptr, 1891 png_alloc_size_t size), PNG_ALLOCATED); 1892 1893/* Frees a pointer allocated by png_malloc() */ 1894PNG_EXPORT(97, void, png_free, (png_structp png_ptr, png_voidp ptr)); 1895 1896/* Free data that was allocated internally */ 1897PNG_EXPORT(98, void, png_free_data, 1898 (png_structp png_ptr, png_infop info_ptr, png_uint_32 free_me, int num)); 1899 1900/* Reassign responsibility for freeing existing data, whether allocated 1901 * by libpng or by the application */ 1902PNG_EXPORT(99, void, png_data_freer, 1903 (png_structp png_ptr, png_infop info_ptr, int freer, png_uint_32 mask)); 1904 1905/* Assignments for png_data_freer */ 1906#define PNG_DESTROY_WILL_FREE_DATA 1 1907#define PNG_SET_WILL_FREE_DATA 1 1908#define PNG_USER_WILL_FREE_DATA 2 1909/* Flags for png_ptr->free_me and info_ptr->free_me */ 1910#define PNG_FREE_HIST 0x0008 1911#define PNG_FREE_ICCP 0x0010 1912#define PNG_FREE_SPLT 0x0020 1913#define PNG_FREE_ROWS 0x0040 1914#define PNG_FREE_PCAL 0x0080 1915#define PNG_FREE_SCAL 0x0100 1916#define PNG_FREE_UNKN 0x0200 1917#define PNG_FREE_LIST 0x0400 1918#define PNG_FREE_PLTE 0x1000 1919#define PNG_FREE_TRNS 0x2000 1920#define PNG_FREE_TEXT 0x4000 1921#define PNG_FREE_ALL 0x7fff 1922#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ 1923 1924#ifdef PNG_USER_MEM_SUPPORTED 1925PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_structp png_ptr, 1926 png_alloc_size_t size), PNG_ALLOCATED); 1927PNG_EXPORT(101, void, png_free_default, (png_structp png_ptr, png_voidp ptr)); 1928#endif 1929 1930#ifdef PNG_ERROR_TEXT_SUPPORTED 1931/* Fatal error in PNG image of libpng - can't continue */ 1932PNG_EXPORTA(102, void, png_error, 1933 (png_structp png_ptr, png_const_charp error_message), 1934 PNG_NORETURN); 1935 1936/* The same, but the chunk name is prepended to the error string. */ 1937PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr, 1938 png_const_charp error_message), PNG_NORETURN); 1939 1940#else 1941/* Fatal error in PNG image of libpng - can't continue */ 1942PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN); 1943#endif 1944 1945#ifdef PNG_WARNINGS_SUPPORTED 1946/* Non-fatal error in libpng. Can continue, but may have a problem. */ 1947PNG_EXPORT(105, void, png_warning, (png_structp png_ptr, 1948 png_const_charp warning_message)); 1949 1950/* Non-fatal error in libpng, chunk name is prepended to message. */ 1951PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr, 1952 png_const_charp warning_message)); 1953#endif 1954 1955#ifdef PNG_BENIGN_ERRORS_SUPPORTED 1956/* Benign error in libpng. Can continue, but may have a problem. 1957 * User can choose whether to handle as a fatal error or as a warning. */ 1958# undef png_benign_error 1959PNG_EXPORT(107, void, png_benign_error, (png_structp png_ptr, 1960 png_const_charp warning_message)); 1961 1962/* Same, chunk name is prepended to message. */ 1963# undef png_chunk_benign_error 1964PNG_EXPORT(108, void, png_chunk_benign_error, (png_structp png_ptr, 1965 png_const_charp warning_message)); 1966 1967PNG_EXPORT(109, void, png_set_benign_errors, 1968 (png_structp png_ptr, int allowed)); 1969#else 1970# ifdef PNG_ALLOW_BENIGN_ERRORS 1971# define png_benign_error png_warning 1972# define png_chunk_benign_error png_chunk_warning 1973# else 1974# define png_benign_error png_error 1975# define png_chunk_benign_error png_chunk_error 1976# endif 1977#endif 1978 1979/* The png_set_<chunk> functions are for storing values in the png_info_struct. 1980 * Similarly, the png_get_<chunk> calls are used to read values from the 1981 * png_info_struct, either storing the parameters in the passed variables, or 1982 * setting pointers into the png_info_struct where the data is stored. The 1983 * png_get_<chunk> functions return a non-zero value if the data was available 1984 * in info_ptr, or return zero and do not change any of the parameters if the 1985 * data was not available. 1986 * 1987 * These functions should be used instead of directly accessing png_info 1988 * to avoid problems with future changes in the size and internal layout of 1989 * png_info_struct. 1990 */ 1991/* Returns "flag" if chunk data is valid in info_ptr. */ 1992PNG_EXPORT(110, png_uint_32, png_get_valid, 1993 (png_const_structp png_ptr, png_const_infop info_ptr, 1994 png_uint_32 flag)); 1995 1996/* Returns number of bytes needed to hold a transformed row. */ 1997PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structp png_ptr, 1998 png_const_infop info_ptr)); 1999 2000#ifdef PNG_INFO_IMAGE_SUPPORTED 2001/* Returns row_pointers, which is an array of pointers to scanlines that was 2002 * returned from png_read_png(). 2003 */ 2004PNG_EXPORT(112, png_bytepp, png_get_rows, 2005 (png_const_structp png_ptr, png_const_infop info_ptr)); 2006/* Set row_pointers, which is an array of pointers to scanlines for use 2007 * by png_write_png(). 2008 */ 2009PNG_EXPORT(113, void, png_set_rows, (png_structp png_ptr, 2010 png_infop info_ptr, png_bytepp row_pointers)); 2011#endif 2012 2013/* Returns number of color channels in image. */ 2014PNG_EXPORT(114, png_byte, png_get_channels, 2015 (png_const_structp png_ptr, png_const_infop info_ptr)); 2016 2017#ifdef PNG_EASY_ACCESS_SUPPORTED 2018/* Returns image width in pixels. */ 2019PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structp png_ptr, 2020 png_const_infop info_ptr)); 2021 2022/* Returns image height in pixels. */ 2023PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structp png_ptr, 2024 png_const_infop info_ptr)); 2025 2026/* Returns image bit_depth. */ 2027PNG_EXPORT(117, png_byte, png_get_bit_depth, 2028 (png_const_structp png_ptr, png_const_infop info_ptr)); 2029 2030/* Returns image color_type. */ 2031PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structp png_ptr, 2032 png_const_infop info_ptr)); 2033 2034/* Returns image filter_type. */ 2035PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structp png_ptr, 2036 png_const_infop info_ptr)); 2037 2038/* Returns image interlace_type. */ 2039PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structp png_ptr, 2040 png_const_infop info_ptr)); 2041 2042/* Returns image compression_type. */ 2043PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structp png_ptr, 2044 png_const_infop info_ptr)); 2045 2046/* Returns image resolution in pixels per meter, from pHYs chunk data. */ 2047PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, 2048 (png_const_structp png_ptr, png_const_infop info_ptr)); 2049PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, 2050 (png_const_structp png_ptr, png_const_infop info_ptr)); 2051PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, 2052 (png_const_structp png_ptr, png_const_infop info_ptr)); 2053 2054/* Returns pixel aspect ratio, computed from pHYs chunk data. */ 2055PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, 2056 (png_const_structp png_ptr, png_const_infop info_ptr)); 2057PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, 2058 (png_const_structp png_ptr, png_const_infop info_ptr)); 2059 2060/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ 2061PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, 2062 (png_const_structp png_ptr, png_const_infop info_ptr)); 2063PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, 2064 (png_const_structp png_ptr, png_const_infop info_ptr)); 2065PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, 2066 (png_const_structp png_ptr, png_const_infop info_ptr)); 2067PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, 2068 (png_const_structp png_ptr, png_const_infop info_ptr)); 2069 2070#endif /* PNG_EASY_ACCESS_SUPPORTED */ 2071 2072/* Returns pointer to signature string read from PNG header */ 2073PNG_EXPORT(130, png_const_bytep, png_get_signature, 2074 (png_const_structp png_ptr, png_infop info_ptr)); 2075 2076#ifdef PNG_bKGD_SUPPORTED 2077PNG_EXPORT(131, png_uint_32, png_get_bKGD, 2078 (png_const_structp png_ptr, png_infop info_ptr, 2079 png_color_16p *background)); 2080#endif 2081 2082#ifdef PNG_bKGD_SUPPORTED 2083PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr, 2084 png_const_color_16p background)); 2085#endif 2086 2087#ifdef PNG_cHRM_SUPPORTED 2088PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structp png_ptr, 2089 png_const_infop info_ptr, double *white_x, double *white_y, double *red_x, 2090 double *red_y, double *green_x, double *green_y, double *blue_x, 2091 double *blue_y)); 2092PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_structp png_ptr, 2093 png_const_infop info_ptr, double *red_X, double *red_Y, double *red_Z, 2094 double *green_X, double *green_Y, double *green_Z, double *blue_X, 2095 double *blue_Y, double *blue_Z)); 2096#ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */ 2097PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, 2098 (png_const_structp png_ptr, 2099 png_const_infop info_ptr, png_fixed_point *int_white_x, 2100 png_fixed_point *int_white_y, png_fixed_point *int_red_x, 2101 png_fixed_point *int_red_y, png_fixed_point *int_green_x, 2102 png_fixed_point *int_green_y, png_fixed_point *int_blue_x, 2103 png_fixed_point *int_blue_y)); 2104#endif 2105PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, 2106 (png_structp png_ptr, png_const_infop info_ptr, 2107 png_fixed_point *int_red_X, png_fixed_point *int_red_Y, 2108 png_fixed_point *int_red_Z, png_fixed_point *int_green_X, 2109 png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, 2110 png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, 2111 png_fixed_point *int_blue_Z)); 2112#endif 2113 2114#ifdef PNG_cHRM_SUPPORTED 2115PNG_FP_EXPORT(135, void, png_set_cHRM, 2116 (png_structp png_ptr, png_infop info_ptr, 2117 double white_x, double white_y, double red_x, double red_y, double green_x, 2118 double green_y, double blue_x, double blue_y)); 2119PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_structp png_ptr, 2120 png_infop info_ptr, double red_X, double red_Y, double red_Z, 2121 double green_X, double green_Y, double green_Z, double blue_X, 2122 double blue_Y, double blue_Z)); 2123PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_structp png_ptr, 2124 png_infop info_ptr, png_fixed_point int_white_x, 2125 png_fixed_point int_white_y, png_fixed_point int_red_x, 2126 png_fixed_point int_red_y, png_fixed_point int_green_x, 2127 png_fixed_point int_green_y, png_fixed_point int_blue_x, 2128 png_fixed_point int_blue_y)); 2129PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_structp png_ptr, 2130 png_infop info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, 2131 png_fixed_point int_red_Z, png_fixed_point int_green_X, 2132 png_fixed_point int_green_Y, png_fixed_point int_green_Z, 2133 png_fixed_point int_blue_X, png_fixed_point int_blue_Y, 2134 png_fixed_point int_blue_Z)); 2135#endif 2136 2137#ifdef PNG_gAMA_SUPPORTED 2138PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, 2139 (png_const_structp png_ptr, png_const_infop info_ptr, 2140 double *file_gamma)); 2141PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, 2142 (png_const_structp png_ptr, png_const_infop info_ptr, 2143 png_fixed_point *int_file_gamma)); 2144#endif 2145 2146#ifdef PNG_gAMA_SUPPORTED 2147PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr, 2148 png_infop info_ptr, double file_gamma)); 2149PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr, 2150 png_infop info_ptr, png_fixed_point int_file_gamma)); 2151#endif 2152 2153#ifdef PNG_hIST_SUPPORTED 2154PNG_EXPORT(141, png_uint_32, png_get_hIST, 2155 (png_const_structp png_ptr, png_const_infop info_ptr, 2156 png_uint_16p *hist)); 2157#endif 2158 2159#ifdef PNG_hIST_SUPPORTED 2160PNG_EXPORT(142, void, png_set_hIST, (png_structp png_ptr, 2161 png_infop info_ptr, png_const_uint_16p hist)); 2162#endif 2163 2164PNG_EXPORT(143, png_uint_32, png_get_IHDR, 2165 (png_structp png_ptr, png_infop info_ptr, 2166 png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type, 2167 int *interlace_method, int *compression_method, int *filter_method)); 2168 2169PNG_EXPORT(144, void, png_set_IHDR, 2170 (png_structp png_ptr, png_infop info_ptr, 2171 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, 2172 int interlace_method, int compression_method, int filter_method)); 2173 2174#ifdef PNG_oFFs_SUPPORTED 2175PNG_EXPORT(145, png_uint_32, png_get_oFFs, 2176 (png_const_structp png_ptr, png_const_infop info_ptr, 2177 png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)); 2178#endif 2179 2180#ifdef PNG_oFFs_SUPPORTED 2181PNG_EXPORT(146, void, png_set_oFFs, 2182 (png_structp png_ptr, png_infop info_ptr, 2183 png_int_32 offset_x, png_int_32 offset_y, int unit_type)); 2184#endif 2185 2186#ifdef PNG_pCAL_SUPPORTED 2187PNG_EXPORT(147, png_uint_32, png_get_pCAL, 2188 (png_const_structp png_ptr, png_const_infop info_ptr, 2189 png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, 2190 int *nparams, 2191 png_charp *units, png_charpp *params)); 2192#endif 2193 2194#ifdef PNG_pCAL_SUPPORTED 2195PNG_EXPORT(148, void, png_set_pCAL, (png_structp png_ptr, 2196 png_infop info_ptr, 2197 png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type, 2198 int nparams, png_const_charp units, png_charpp params)); 2199#endif 2200 2201#ifdef PNG_pHYs_SUPPORTED 2202PNG_EXPORT(149, png_uint_32, png_get_pHYs, 2203 (png_const_structp png_ptr, png_const_infop info_ptr, 2204 png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)); 2205#endif 2206 2207#ifdef PNG_pHYs_SUPPORTED 2208PNG_EXPORT(150, void, png_set_pHYs, 2209 (png_structp png_ptr, png_infop info_ptr, 2210 png_uint_32 res_x, png_uint_32 res_y, int unit_type)); 2211#endif 2212 2213PNG_EXPORT(151, png_uint_32, png_get_PLTE, 2214 (png_const_structp png_ptr, png_const_infop info_ptr, 2215 png_colorp *palette, int *num_palette)); 2216 2217PNG_EXPORT(152, void, png_set_PLTE, 2218 (png_structp png_ptr, png_infop info_ptr, 2219 png_const_colorp palette, int num_palette)); 2220 2221#ifdef PNG_sBIT_SUPPORTED 2222PNG_EXPORT(153, png_uint_32, png_get_sBIT, 2223 (png_const_structp png_ptr, png_infop info_ptr, 2224 png_color_8p *sig_bit)); 2225#endif 2226 2227#ifdef PNG_sBIT_SUPPORTED 2228PNG_EXPORT(154, void, png_set_sBIT, 2229 (png_structp png_ptr, png_infop info_ptr, png_const_color_8p sig_bit)); 2230#endif 2231 2232#ifdef PNG_sRGB_SUPPORTED 2233PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structp png_ptr, 2234 png_const_infop info_ptr, int *file_srgb_intent)); 2235#endif 2236 2237#ifdef PNG_sRGB_SUPPORTED 2238PNG_EXPORT(156, void, png_set_sRGB, 2239 (png_structp png_ptr, png_infop info_ptr, int srgb_intent)); 2240PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_structp png_ptr, 2241 png_infop info_ptr, int srgb_intent)); 2242#endif 2243 2244#ifdef PNG_iCCP_SUPPORTED 2245PNG_EXPORT(158, png_uint_32, png_get_iCCP, 2246 (png_const_structp png_ptr, png_const_infop info_ptr, 2247 png_charpp name, int *compression_type, png_bytepp profile, 2248 png_uint_32 *proflen)); 2249#endif 2250 2251#ifdef PNG_iCCP_SUPPORTED 2252PNG_EXPORT(159, void, png_set_iCCP, 2253 (png_structp png_ptr, png_infop info_ptr, 2254 png_const_charp name, int compression_type, png_const_bytep profile, 2255 png_uint_32 proflen)); 2256#endif 2257 2258#ifdef PNG_sPLT_SUPPORTED 2259PNG_EXPORT(160, png_uint_32, png_get_sPLT, 2260 (png_const_structp png_ptr, png_const_infop info_ptr, 2261 png_sPLT_tpp entries)); 2262#endif 2263 2264#ifdef PNG_sPLT_SUPPORTED 2265PNG_EXPORT(161, void, png_set_sPLT, 2266 (png_structp png_ptr, png_infop info_ptr, 2267 png_const_sPLT_tp entries, int nentries)); 2268#endif 2269 2270#ifdef PNG_TEXT_SUPPORTED 2271/* png_get_text also returns the number of text chunks in *num_text */ 2272PNG_EXPORT(162, png_uint_32, png_get_text, 2273 (png_const_structp png_ptr, png_const_infop info_ptr, 2274 png_textp *text_ptr, int *num_text)); 2275#endif 2276 2277/* Note while png_set_text() will accept a structure whose text, 2278 * language, and translated keywords are NULL pointers, the structure 2279 * returned by png_get_text will always contain regular 2280 * zero-terminated C strings. They might be empty strings but 2281 * they will never be NULL pointers. 2282 */ 2283 2284#ifdef PNG_TEXT_SUPPORTED 2285PNG_EXPORT(163, void, png_set_text, 2286 (png_structp png_ptr, png_infop info_ptr, 2287 png_const_textp text_ptr, int num_text)); 2288#endif 2289 2290#ifdef PNG_tIME_SUPPORTED 2291PNG_EXPORT(164, png_uint_32, png_get_tIME, 2292 (png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time)); 2293#endif 2294 2295#ifdef PNG_tIME_SUPPORTED 2296PNG_EXPORT(165, void, png_set_tIME, 2297 (png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time)); 2298#endif 2299 2300#ifdef PNG_tRNS_SUPPORTED 2301PNG_EXPORT(166, png_uint_32, png_get_tRNS, 2302 (png_const_structp png_ptr, png_infop info_ptr, 2303 png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)); 2304#endif 2305 2306#ifdef PNG_tRNS_SUPPORTED 2307PNG_EXPORT(167, void, png_set_tRNS, 2308 (png_structp png_ptr, png_infop info_ptr, 2309 png_const_bytep trans_alpha, int num_trans, 2310 png_const_color_16p trans_color)); 2311#endif 2312 2313#ifdef PNG_sCAL_SUPPORTED 2314PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, 2315 (png_const_structp png_ptr, png_const_infop info_ptr, 2316 int *unit, double *width, double *height)); 2317#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED 2318/* NOTE: this API is currently implemented using floating point arithmetic, 2319 * consequently it can only be used on systems with floating point support. 2320 * In any case the range of values supported by png_fixed_point is small and it 2321 * is highly recommended that png_get_sCAL_s be used instead. 2322 */ 2323PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, 2324 (png_structp png_ptr, png_const_infop info_ptr, int *unit, 2325 png_fixed_point *width, 2326 png_fixed_point *height)); 2327#endif 2328PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, 2329 (png_const_structp png_ptr, png_const_infop info_ptr, 2330 int *unit, png_charpp swidth, png_charpp sheight)); 2331 2332PNG_FP_EXPORT(170, void, png_set_sCAL, 2333 (png_structp png_ptr, png_infop info_ptr, 2334 int unit, double width, double height)); 2335PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr, 2336 png_infop info_ptr, int unit, png_fixed_point width, 2337 png_fixed_point height)); 2338PNG_EXPORT(171, void, png_set_sCAL_s, 2339 (png_structp png_ptr, png_infop info_ptr, 2340 int unit, png_const_charp swidth, png_const_charp sheight)); 2341#endif /* PNG_sCAL_SUPPORTED */ 2342 2343#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED 2344/* Provide a list of chunks and how they are to be handled, if the built-in 2345 handling or default unknown chunk handling is not desired. Any chunks not 2346 listed will be handled in the default manner. The IHDR and IEND chunks 2347 must not be listed. Because this turns off the default handling for chunks 2348 that would otherwise be recognized the behavior of libpng transformations may 2349 well become incorrect! 2350 keep = 0: PNG_HANDLE_CHUNK_AS_DEFAULT: follow default behavior 2351 = 1: PNG_HANDLE_CHUNK_NEVER: do not keep 2352 = 2: PNG_HANDLE_CHUNK_IF_SAFE: keep only if safe-to-copy 2353 = 3: PNG_HANDLE_CHUNK_ALWAYS: keep even if unsafe-to-copy 2354*/ 2355PNG_EXPORT(172, void, png_set_keep_unknown_chunks, 2356 (png_structp png_ptr, int keep, 2357 png_const_bytep chunk_list, int num_chunks)); 2358 2359/* The handling code is returned; the result is therefore true (non-zero) if 2360 * special handling is required, false for the default handling. 2361 */ 2362PNG_EXPORT(173, int, png_handle_as_unknown, (png_structp png_ptr, 2363 png_const_bytep chunk_name)); 2364#endif 2365#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED 2366PNG_EXPORT(174, void, png_set_unknown_chunks, (png_structp png_ptr, 2367 png_infop info_ptr, png_const_unknown_chunkp unknowns, 2368 int num_unknowns)); 2369PNG_EXPORT(175, void, png_set_unknown_chunk_location, 2370 (png_structp png_ptr, png_infop info_ptr, int chunk, int location)); 2371PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structp png_ptr, 2372 png_const_infop info_ptr, png_unknown_chunkpp entries)); 2373#endif 2374 2375/* Png_free_data() will turn off the "valid" flag for anything it frees. 2376 * If you need to turn it off for a chunk that your application has freed, 2377 * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); 2378 */ 2379PNG_EXPORT(177, void, png_set_invalid, 2380 (png_structp png_ptr, png_infop info_ptr, int mask)); 2381 2382#ifdef PNG_INFO_IMAGE_SUPPORTED 2383/* The "params" pointer is currently not used and is for future expansion. */ 2384PNG_EXPORT(178, void, png_read_png, (png_structp png_ptr, png_infop info_ptr, 2385 int transforms, png_voidp params)); 2386PNG_EXPORT(179, void, png_write_png, (png_structp png_ptr, png_infop info_ptr, 2387 int transforms, png_voidp params)); 2388#endif 2389 2390PNG_EXPORT(180, png_const_charp, png_get_copyright, 2391 (png_const_structp png_ptr)); 2392PNG_EXPORT(181, png_const_charp, png_get_header_ver, 2393 (png_const_structp png_ptr)); 2394PNG_EXPORT(182, png_const_charp, png_get_header_version, 2395 (png_const_structp png_ptr)); 2396PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, 2397 (png_const_structp png_ptr)); 2398 2399#ifdef PNG_MNG_FEATURES_SUPPORTED 2400PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structp png_ptr, 2401 png_uint_32 mng_features_permitted)); 2402#endif 2403 2404/* For use in png_set_keep_unknown, added to version 1.2.6 */ 2405#define PNG_HANDLE_CHUNK_AS_DEFAULT 0 2406#define PNG_HANDLE_CHUNK_NEVER 1 2407#define PNG_HANDLE_CHUNK_IF_SAFE 2 2408#define PNG_HANDLE_CHUNK_ALWAYS 3 2409 2410/* Strip the prepended error numbers ("#nnn ") from error and warning 2411 * messages before passing them to the error or warning handler. 2412 */ 2413#ifdef PNG_ERROR_NUMBERS_SUPPORTED 2414PNG_EXPORT(185, void, png_set_strip_error_numbers, 2415 (png_structp png_ptr, 2416 png_uint_32 strip_mode)); 2417#endif 2418 2419/* Added in libpng-1.2.6 */ 2420#ifdef PNG_SET_USER_LIMITS_SUPPORTED 2421PNG_EXPORT(186, void, png_set_user_limits, (png_structp png_ptr, 2422 png_uint_32 user_width_max, png_uint_32 user_height_max)); 2423PNG_EXPORT(187, png_uint_32, png_get_user_width_max, 2424 (png_const_structp png_ptr)); 2425PNG_EXPORT(188, png_uint_32, png_get_user_height_max, 2426 (png_const_structp png_ptr)); 2427/* Added in libpng-1.4.0 */ 2428PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structp png_ptr, 2429 png_uint_32 user_chunk_cache_max)); 2430PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, 2431 (png_const_structp png_ptr)); 2432/* Added in libpng-1.4.1 */ 2433PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structp png_ptr, 2434 png_alloc_size_t user_chunk_cache_max)); 2435PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, 2436 (png_const_structp png_ptr)); 2437#endif 2438 2439#if defined(PNG_INCH_CONVERSIONS_SUPPORTED) 2440PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, 2441 (png_const_structp png_ptr, png_const_infop info_ptr)); 2442 2443PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, 2444 (png_const_structp png_ptr, png_const_infop info_ptr)); 2445 2446PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, 2447 (png_const_structp png_ptr, png_const_infop info_ptr)); 2448 2449PNG_FP_EXPORT(196, float, png_get_x_offset_inches, 2450 (png_const_structp png_ptr, png_const_infop info_ptr)); 2451#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ 2452PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, 2453 (png_structp png_ptr, png_const_infop info_ptr)); 2454#endif 2455 2456PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr, 2457 png_const_infop info_ptr)); 2458#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ 2459PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, 2460 (png_structp png_ptr, png_const_infop info_ptr)); 2461#endif 2462 2463# ifdef PNG_pHYs_SUPPORTED 2464PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structp png_ptr, 2465 png_const_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, 2466 int *unit_type)); 2467# endif /* PNG_pHYs_SUPPORTED */ 2468#endif /* PNG_INCH_CONVERSIONS_SUPPORTED */ 2469 2470/* Added in libpng-1.4.0 */ 2471#ifdef PNG_IO_STATE_SUPPORTED 2472PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_structp png_ptr)); 2473 2474PNG_EXPORTA(200, png_const_bytep, png_get_io_chunk_name, 2475 (png_structp png_ptr), PNG_DEPRECATED); 2476PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, 2477 (png_const_structp png_ptr)); 2478 2479/* The flags returned by png_get_io_state() are the following: */ 2480# define PNG_IO_NONE 0x0000 /* no I/O at this moment */ 2481# define PNG_IO_READING 0x0001 /* currently reading */ 2482# define PNG_IO_WRITING 0x0002 /* currently writing */ 2483# define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ 2484# define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ 2485# define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ 2486# define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ 2487# define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ 2488# define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ 2489#endif /* ?PNG_IO_STATE_SUPPORTED */ 2490 2491/* Interlace support. The following macros are always defined so that if 2492 * libpng interlace handling is turned off the macros may be used to handle 2493 * interlaced images within the application. 2494 */ 2495#define PNG_INTERLACE_ADAM7_PASSES 7 2496 2497/* Two macros to return the first row and first column of the original, 2498 * full, image which appears in a given pass. 'pass' is in the range 0 2499 * to 6 and the result is in the range 0 to 7. 2500 */ 2501#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) 2502#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) 2503 2504/* A macro to return the offset between pixels in the output row for a pair of 2505 * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that 2506 * follows. Note that ROW_OFFSET is the offset from one row to the next whereas 2507 * COL_OFFSET is from one column to the next, within a row. 2508 */ 2509#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) 2510#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) 2511 2512/* Two macros to help evaluate the number of rows or columns in each 2513 * pass. This is expressed as a shift - effectively log2 of the number or 2514 * rows or columns in each 8x8 tile of the original image. 2515 */ 2516#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) 2517#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) 2518 2519/* Hence two macros to determine the number of rows or columns in a given 2520 * pass of an image given its height or width. In fact these macros may 2521 * return non-zero even though the sub-image is empty, because the other 2522 * dimension may be empty for a small image. 2523 */ 2524#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ 2525 -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) 2526#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ 2527 -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) 2528 2529/* For the reader row callbacks (both progressive and sequential) it is 2530 * necessary to find the row in the output image given a row in an interlaced 2531 * image, so two more macros: 2532 */ 2533#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \ 2534 (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) 2535#define PNG_COL_FROM_PASS_COL(xIn, pass) \ 2536 (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) 2537 2538/* Two macros which return a boolean (0 or 1) saying whether the given row 2539 * or column is in a particular pass. These use a common utility macro that 2540 * returns a mask for a given pass - the offset 'off' selects the row or 2541 * column version. The mask has the appropriate bit set for each column in 2542 * the tile. 2543 */ 2544#define PNG_PASS_MASK(pass,off) ( \ 2545 ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \ 2546 ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) 2547 2548#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ 2549 ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) 2550#define PNG_COL_IN_INTERLACE_PASS(x, pass) \ 2551 ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) 2552 2553#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED 2554/* With these routines we avoid an integer divide, which will be slower on 2555 * most machines. However, it does take more operations than the corresponding 2556 * divide method, so it may be slower on a few RISC systems. There are two 2557 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. 2558 * 2559 * Note that the rounding factors are NOT supposed to be the same! 128 and 2560 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the 2561 * standard method. 2562 * 2563 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] 2564 */ 2565 2566 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ 2567 2568# define png_composite(composite, fg, alpha, bg) \ 2569 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ 2570 * (png_uint_16)(alpha) \ 2571 + (png_uint_16)(bg)*(png_uint_16)(255 \ 2572 - (png_uint_16)(alpha)) + 128); \ 2573 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } 2574 2575# define png_composite_16(composite, fg, alpha, bg) \ 2576 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ 2577 * (png_uint_32)(alpha) \ 2578 + (png_uint_32)(bg)*(65535 \ 2579 - (png_uint_32)(alpha)) + 32768); \ 2580 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } 2581 2582#else /* Standard method using integer division */ 2583 2584# define png_composite(composite, fg, alpha, bg) \ 2585 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ 2586 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ 2587 127) / 255) 2588 2589# define png_composite_16(composite, fg, alpha, bg) \ 2590 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ 2591 (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ 2592 32767) / 65535) 2593#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */ 2594 2595#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED 2596PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); 2597PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); 2598PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); 2599#endif 2600 2601PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_structp png_ptr, 2602 png_const_bytep buf)); 2603/* No png_get_int_16 -- may be added if there's a real need for it. */ 2604 2605/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ 2606#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED 2607PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); 2608#endif 2609#ifdef PNG_SAVE_INT_32_SUPPORTED 2610PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); 2611#endif 2612 2613/* Place a 16-bit number into a buffer in PNG byte order. 2614 * The parameter is declared unsigned int, not png_uint_16, 2615 * just to avoid potential problems on pre-ANSI C compilers. 2616 */ 2617#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED 2618PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); 2619/* No png_save_int_16 -- may be added if there's a real need for it. */ 2620#endif 2621 2622#ifdef PNG_USE_READ_MACROS 2623/* Inline macros to do direct reads of bytes from the input buffer. 2624 * The png_get_int_32() routine assumes we are using two's complement 2625 * format for negative values, which is almost certainly true. 2626 */ 2627# define png_get_uint_32(buf) \ 2628 (((png_uint_32)(*(buf)) << 24) + \ 2629 ((png_uint_32)(*((buf) + 1)) << 16) + \ 2630 ((png_uint_32)(*((buf) + 2)) << 8) + \ 2631 ((png_uint_32)(*((buf) + 3)))) 2632 2633 /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the 2634 * function) incorrectly returned a value of type png_uint_32. 2635 */ 2636# define png_get_uint_16(buf) \ 2637 ((png_uint_16) \ 2638 (((unsigned int)(*(buf)) << 8) + \ 2639 ((unsigned int)(*((buf) + 1))))) 2640 2641# define png_get_int_32(buf) \ 2642 ((png_int_32)((*(buf) & 0x80) \ 2643 ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \ 2644 : (png_int_32)png_get_uint_32(buf))) 2645#endif 2646 2647#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \ 2648 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED) 2649PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr, 2650 int allowed)); 2651#endif 2652 2653/* Maintainer: Put new public prototypes here ^, in libpng.3, and project 2654 * defs 2655 */ 2656 2657/* The last ordinal number (this is the *last* one already used; the next 2658 * one to use is one more than this.) Maintainer, remember to add an entry to 2659 * scripts/symbols.def as well. 2660 */ 2661#ifdef PNG_EXPORT_LAST_ORDINAL 2662 PNG_EXPORT_LAST_ORDINAL(234); 2663#endif 2664 2665#ifdef __cplusplus 2666} 2667#endif 2668 2669#endif /* PNG_VERSION_INFO_ONLY */ 2670/* Do not put anything past this line */ 2671#endif /* PNG_H */ 2672