| 1 | |
|---|---|
| 2 | /* png.h - header file for PNG reference library |
| 3 | * |
| 4 | * libpng version 1.6.38.git |
| 5 | * |
| 6 | * Copyright (c) 2018-2020 Cosmin Truta |
| 7 | * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson |
| 8 | * Copyright (c) 1996-1997 Andreas Dilger |
| 9 | * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
| 10 | * |
| 11 | * This code is released under the libpng license. (See LICENSE, below.) |
| 12 | * |
| 13 | * Authors and maintainers: |
| 14 | * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat |
| 15 | * libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger |
| 16 | * libpng versions 0.97, January 1998, through 1.6.35, July 2018: |
| 17 | * Glenn Randers-Pehrson |
| 18 | * libpng versions 1.6.36, December 2018, through 1.6.37, April 2019: |
| 19 | * Cosmin Truta |
| 20 | * See also "Contributing Authors", below. |
| 21 | */ |
| 22 | |
| 23 | /* |
| 24 | * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE |
| 25 | * ========================================= |
| 26 | * |
| 27 | * PNG Reference Library License version 2 |
| 28 | * --------------------------------------- |
| 29 | * |
| 30 | * * Copyright (c) 1995-2020 The PNG Reference Library Authors. |
| 31 | * * Copyright (c) 2018-2020 Cosmin Truta. |
| 32 | * * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson. |
| 33 | * * Copyright (c) 1996-1997 Andreas Dilger. |
| 34 | * * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
| 35 | * |
| 36 | * The software is supplied "as is", without warranty of any kind, |
| 37 | * express or implied, including, without limitation, the warranties |
| 38 | * of merchantability, fitness for a particular purpose, title, and |
| 39 | * non-infringement. In no event shall the Copyright owners, or |
| 40 | * anyone distributing the software, be liable for any damages or |
| 41 | * other liability, whether in contract, tort or otherwise, arising |
| 42 | * from, out of, or in connection with the software, or the use or |
| 43 | * other dealings in the software, even if advised of the possibility |
| 44 | * of such damage. |
| 45 | * |
| 46 | * Permission is hereby granted to use, copy, modify, and distribute |
| 47 | * this software, or portions hereof, for any purpose, without fee, |
| 48 | * subject to the following restrictions: |
| 49 | * |
| 50 | * 1. The origin of this software must not be misrepresented; you |
| 51 | * must not claim that you wrote the original software. If you |
| 52 | * use this software in a product, an acknowledgment in the product |
| 53 | * documentation would be appreciated, but is not required. |
| 54 | * |
| 55 | * 2. Altered source versions must be plainly marked as such, and must |
| 56 | * not be misrepresented as being the original software. |
| 57 | * |
| 58 | * 3. This Copyright notice may not be removed or altered from any |
| 59 | * source or altered source distribution. |
| 60 | * |
| 61 | * |
| 62 | * PNG Reference Library License version 1 (for libpng 0.5 through 1.6.35) |
| 63 | * ----------------------------------------------------------------------- |
| 64 | * |
| 65 | * libpng versions 1.0.7, July 1, 2000, through 1.6.35, July 15, 2018 are |
| 66 | * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson, are |
| 67 | * derived from libpng-1.0.6, and are distributed according to the same |
| 68 | * disclaimer and license as libpng-1.0.6 with the following individuals |
| 69 | * added to the list of Contributing Authors: |
| 70 | * |
| 71 | * Simon-Pierre Cadieux |
| 72 | * Eric S. Raymond |
| 73 | * Mans Rullgard |
| 74 | * Cosmin Truta |
| 75 | * Gilles Vollant |
| 76 | * James Yu |
| 77 | * Mandar Sahastrabuddhe |
| 78 | * Google Inc. |
| 79 | * Vadim Barkov |
| 80 | * |
| 81 | * and with the following additions to the disclaimer: |
| 82 | * |
| 83 | * There is no warranty against interference with your enjoyment of |
| 84 | * the library or against infringement. There is no warranty that our |
| 85 | * efforts or the library will fulfill any of your particular purposes |
| 86 | * or needs. This library is provided with all faults, and the entire |
| 87 | * risk of satisfactory quality, performance, accuracy, and effort is |
| 88 | * with the user. |
| 89 | * |
| 90 | * Some files in the "contrib" directory and some configure-generated |
| 91 | * files that are distributed with libpng have other copyright owners, and |
| 92 | * are released under other open source licenses. |
| 93 | * |
| 94 | * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are |
| 95 | * Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from |
| 96 | * libpng-0.96, and are distributed according to the same disclaimer and |
| 97 | * license as libpng-0.96, with the following individuals added to the |
| 98 | * list of Contributing Authors: |
| 99 | * |
| 100 | * Tom Lane |
| 101 | * Glenn Randers-Pehrson |
| 102 | * Willem van Schaik |
| 103 | * |
| 104 | * libpng versions 0.89, June 1996, through 0.96, May 1997, are |
| 105 | * Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88, |
| 106 | * and are distributed according to the same disclaimer and license as |
| 107 | * libpng-0.88, with the following individuals added to the list of |
| 108 | * Contributing Authors: |
| 109 | * |
| 110 | * John Bowler |
| 111 | * Kevin Bracey |
| 112 | * Sam Bushell |
| 113 | * Magnus Holmgren |
| 114 | * Greg Roelofs |
| 115 | * Tom Tanner |
| 116 | * |
| 117 | * Some files in the "scripts" directory have other copyright owners, |
| 118 | * but are released under this license. |
| 119 | * |
| 120 | * libpng versions 0.5, May 1995, through 0.88, January 1996, are |
| 121 | * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
| 122 | * |
| 123 | * For the purposes of this copyright and license, "Contributing Authors" |
| 124 | * is defined as the following set of individuals: |
| 125 | * |
| 126 | * Andreas Dilger |
| 127 | * Dave Martindale |
| 128 | * Guy Eric Schalnat |
| 129 | * Paul Schmidt |
| 130 | * Tim Wegner |
| 131 | * |
| 132 | * The PNG Reference Library is supplied "AS IS". The Contributing |
| 133 | * Authors and Group 42, Inc. disclaim all warranties, expressed or |
| 134 | * implied, including, without limitation, the warranties of |
| 135 | * merchantability and of fitness for any purpose. The Contributing |
| 136 | * Authors and Group 42, Inc. assume no liability for direct, indirect, |
| 137 | * incidental, special, exemplary, or consequential damages, which may |
| 138 | * result from the use of the PNG Reference Library, even if advised of |
| 139 | * the possibility of such damage. |
| 140 | * |
| 141 | * Permission is hereby granted to use, copy, modify, and distribute this |
| 142 | * source code, or portions hereof, for any purpose, without fee, subject |
| 143 | * to the following restrictions: |
| 144 | * |
| 145 | * 1. The origin of this source code must not be misrepresented. |
| 146 | * |
| 147 | * 2. Altered versions must be plainly marked as such and must not |
| 148 | * be misrepresented as being the original source. |
| 149 | * |
| 150 | * 3. This Copyright notice may not be removed or altered from any |
| 151 | * source or altered source distribution. |
| 152 | * |
| 153 | * The Contributing Authors and Group 42, Inc. specifically permit, |
| 154 | * without fee, and encourage the use of this source code as a component |
| 155 | * to supporting the PNG file format in commercial products. If you use |
| 156 | * this source code in a product, acknowledgment is not required but would |
| 157 | * be appreciated. |
| 158 | * |
| 159 | * END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE. |
| 160 | * |
| 161 | * TRADEMARK |
| 162 | * ========= |
| 163 | * |
| 164 | * The name "libpng" has not been registered by the Copyright owners |
| 165 | * as a trademark in any jurisdiction. However, because libpng has |
| 166 | * been distributed and maintained world-wide, continually since 1995, |
| 167 | * the Copyright owners claim "common-law trademark protection" in any |
| 168 | * jurisdiction where common-law trademark is recognized. |
| 169 | */ |
| 170 | |
| 171 | /* |
| 172 | * A "png_get_copyright" function is available, for convenient use in "about" |
| 173 | * boxes and the like: |
| 174 | * |
| 175 | * printf("%s", png_get_copyright(NULL)); |
| 176 | * |
| 177 | * Also, the PNG logo (in PNG format, of course) is supplied in the |
| 178 | * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). |
| 179 | */ |
| 180 | |
| 181 | /* |
| 182 | * The contributing authors would like to thank all those who helped |
| 183 | * with testing, bug fixes, and patience. This wouldn't have been |
| 184 | * possible without all of you. |
| 185 | * |
| 186 | * Thanks to Frank J. T. Wojcik for helping with the documentation. |
| 187 | */ |
| 188 | |
| 189 | /* Note about libpng version numbers: |
| 190 | * |
| 191 | * Due to various miscommunications, unforeseen code incompatibilities |
| 192 | * and occasional factors outside the authors' control, version numbering |
| 193 | * on the library has not always been consistent and straightforward. |
| 194 | * The following table summarizes matters since version 0.89c, which was |
| 195 | * the first widely used release: |
| 196 | * |
| 197 | * source png.h png.h shared-lib |
| 198 | * version string int version |
| 199 | * ------- ------ ----- ---------- |
| 200 | * 0.89c "1.0 beta 3" 0.89 89 1.0.89 |
| 201 | * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] |
| 202 | * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] |
| 203 | * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] |
| 204 | * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] |
| 205 | * 0.97c 0.97 97 2.0.97 |
| 206 | * 0.98 0.98 98 2.0.98 |
| 207 | * 0.99 0.99 98 2.0.99 |
| 208 | * 0.99a-m 0.99 99 2.0.99 |
| 209 | * 1.00 1.00 100 2.1.0 [100 should be 10000] |
| 210 | * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] |
| 211 | * 1.0.1 png.h string is 10001 2.1.0 |
| 212 | * 1.0.1a-e identical to the 10002 from here on, the shared library |
| 213 | * 1.0.2 source version) 10002 is 2.V where V is the source code |
| 214 | * 1.0.2a-b 10003 version, except as noted. |
| 215 | * 1.0.3 10003 |
| 216 | * 1.0.3a-d 10004 |
| 217 | * 1.0.4 10004 |
| 218 | * 1.0.4a-f 10005 |
| 219 | * 1.0.5 (+ 2 patches) 10005 |
| 220 | * 1.0.5a-d 10006 |
| 221 | * 1.0.5e-r 10100 (not source compatible) |
| 222 | * 1.0.5s-v 10006 (not binary compatible) |
| 223 | * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) |
| 224 | * 1.0.6d-f 10007 (still binary incompatible) |
| 225 | * 1.0.6g 10007 |
| 226 | * 1.0.6h 10007 10.6h (testing xy.z so-numbering) |
| 227 | * 1.0.6i 10007 10.6i |
| 228 | * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) |
| 229 | * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) |
| 230 | * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) |
| 231 | * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) |
| 232 | * 1.0.7 1 10007 (still compatible) |
| 233 | * ... |
| 234 | * 1.0.69 10 10069 10.so.0.69[.0] |
| 235 | * ... |
| 236 | * 1.2.59 13 10259 12.so.0.59[.0] |
| 237 | * ... |
| 238 | * 1.4.20 14 10420 14.so.0.20[.0] |
| 239 | * ... |
| 240 | * 1.5.30 15 10530 15.so.15.30[.0] |
| 241 | * ... |
| 242 | * 1.6.37 16 10637 16.so.16.37[.0] |
| 243 | * |
| 244 | * Henceforth the source version will match the shared-library major and |
| 245 | * minor numbers; the shared-library major version number will be used for |
| 246 | * changes in backward compatibility, as it is intended. |
| 247 | * The PNG_LIBPNG_VER macro, which is not used within libpng but is |
| 248 | * available for applications, is an unsigned integer of the form XYYZZ |
| 249 | * corresponding to the source version X.Y.Z (leading zeros in Y and Z). |
| 250 | * Beta versions were given the previous public release number plus a |
| 251 | * letter, until version 1.0.6j; from then on they were given the upcoming |
| 252 | * public release number plus "betaNN" or "rcNN". |
| 253 | * |
| 254 | * Binary incompatibility exists only when applications make direct access |
| 255 | * to the info_ptr or png_ptr members through png.h, and the compiled |
| 256 | * application is loaded with a different version of the library. |
| 257 | * |
| 258 | * DLLNUM will change each time there are forward or backward changes |
| 259 | * in binary compatibility (e.g., when a new feature is added). |
| 260 | * |
| 261 | * See libpng.txt or libpng.3 for more information. The PNG specification |
| 262 | * is available as a W3C Recommendation and as an ISO/IEC Standard; see |
| 263 | * <https://www.w3.org/TR/2003/REC-PNG-20031110/> |
| 264 | */ |
| 265 | |
| 266 | #ifndef PNG_H |
| 267 | #define PNG_H |
| 268 | |
| 269 | /* This is not the place to learn how to use libpng. The file libpng-manual.txt |
| 270 | * describes how to use libpng, and the file example.c summarizes it |
| 271 | * with some code on which to build. This file is useful for looking |
| 272 | * at the actual function definitions and structure components. If that |
| 273 | * file has been stripped from your copy of libpng, you can find it at |
| 274 | * <http://www.libpng.org/pub/png/libpng-manual.txt> |
| 275 | * |
| 276 | * If you just need to read a PNG file and don't want to read the documentation |
| 277 | * skip to the end of this file and read the section entitled 'simplified API'. |
| 278 | */ |
| 279 | |
| 280 | /* Version information for png.h - this should match the version in png.c */ |
| 281 | #define PNG_LIBPNG_VER_STRING "1.6.38.git" |
| 282 | #define PNG_HEADER_VERSION_STRING " libpng version 1.6.38.git\n" |
| 283 | |
| 284 | #define PNG_LIBPNG_VER_SONUM 16 |
| 285 | #define PNG_LIBPNG_VER_DLLNUM 16 |
| 286 | |
| 287 | /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */ |
| 288 | #define PNG_LIBPNG_VER_MAJOR 1 |
| 289 | #define PNG_LIBPNG_VER_MINOR 6 |
| 290 | #define PNG_LIBPNG_VER_RELEASE 38 |
| 291 | |
| 292 | /* This should be zero for a public release, or non-zero for a |
| 293 | * development version. [Deprecated] |
| 294 | */ |
| 295 | #define PNG_LIBPNG_VER_BUILD 1 |
| 296 | |
| 297 | /* Release Status */ |
| 298 | #define PNG_LIBPNG_BUILD_ALPHA 1 |
| 299 | #define PNG_LIBPNG_BUILD_BETA 2 |
| 300 | #define PNG_LIBPNG_BUILD_RC 3 |
| 301 | #define PNG_LIBPNG_BUILD_STABLE 4 |
| 302 | #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 |
| 303 | |
| 304 | /* Release-Specific Flags */ |
| 305 | #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with |
| 306 | PNG_LIBPNG_BUILD_STABLE only */ |
| 307 | #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with |
| 308 | PNG_LIBPNG_BUILD_SPECIAL */ |
| 309 | #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with |
| 310 | PNG_LIBPNG_BUILD_PRIVATE */ |
| 311 | |
| 312 | #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_BETA |
| 313 | |
| 314 | /* Careful here. At one time, Guy wanted to use 082, but that |
| 315 | * would be octal. We must not include leading zeros. |
| 316 | * Versions 0.7 through 1.0.0 were in the range 0 to 100 here |
| 317 | * (only version 1.0.0 was mis-numbered 100 instead of 10000). |
| 318 | * From version 1.0.1 it is: |
| 319 | * XXYYZZ, where XX=major, YY=minor, ZZ=release |
| 320 | */ |
| 321 | #define PNG_LIBPNG_VER 10638 /* 1.6.38.git */ |
| 322 | |
| 323 | /* Library configuration: these options cannot be changed after |
| 324 | * the library has been built. |
| 325 | */ |
| 326 | #ifndef PNGLCONF_H |
| 327 | /* If pnglibconf.h is missing, you can |
| 328 | * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h |
| 329 | */ |
| 330 | # include "pnglibconf.h" |
| 331 | #endif |
| 332 | |
| 333 | #ifndef PNG_VERSION_INFO_ONLY |
| 334 | /* Machine specific configuration. */ |
| 335 | # include "pngconf.h" |
| 336 | #endif |
| 337 | |
| 338 | /* |
| 339 | * Added at libpng-1.2.8 |
| 340 | * |
| 341 | * Ref MSDN: Private as priority over Special |
| 342 | * VS_FF_PRIVATEBUILD File *was not* built using standard release |
| 343 | * procedures. If this value is given, the StringFileInfo block must |
| 344 | * contain a PrivateBuild string. |
| 345 | * |
| 346 | * VS_FF_SPECIALBUILD File *was* built by the original company using |
| 347 | * standard release procedures but is a variation of the standard |
| 348 | * file of the same version number. If this value is given, the |
| 349 | * StringFileInfo block must contain a SpecialBuild string. |
| 350 | */ |
| 351 | |
| 352 | #ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */ |
| 353 | # define PNG_LIBPNG_BUILD_TYPE \ |
| 354 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) |
| 355 | #else |
| 356 | # ifdef PNG_LIBPNG_SPECIALBUILD |
| 357 | # define PNG_LIBPNG_BUILD_TYPE \ |
| 358 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) |
| 359 | # else |
| 360 | # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) |
| 361 | # endif |
| 362 | #endif |
| 363 | |
| 364 | #ifndef PNG_VERSION_INFO_ONLY |
| 365 | |
| 366 | /* Inhibit C++ name-mangling for libpng functions but not for system calls. */ |
| 367 | #ifdef __cplusplus |
| 368 | extern "C"{ |
| 369 | #endif /* __cplusplus */ |
| 370 | |
| 371 | /* Version information for C files, stored in png.c. This had better match |
| 372 | * the version above. |
| 373 | */ |
| 374 | #define png_libpng_ver png_get_header_ver(NULL) |
| 375 | |
| 376 | /* This file is arranged in several sections: |
| 377 | * |
| 378 | * 1. [omitted] |
| 379 | * 2. Any configuration options that can be specified by for the application |
| 380 | * code when it is built. (Build time configuration is in pnglibconf.h) |
| 381 | * 3. Type definitions (base types are defined in pngconf.h), structure |
| 382 | * definitions. |
| 383 | * 4. Exported library functions. |
| 384 | * 5. Simplified API. |
| 385 | * 6. Implementation options. |
| 386 | * |
| 387 | * The library source code has additional files (principally pngpriv.h) that |
| 388 | * allow configuration of the library. |
| 389 | */ |
| 390 | |
| 391 | /* Section 1: [omitted] */ |
| 392 | |
| 393 | /* Section 2: run time configuration |
| 394 | * See pnglibconf.h for build time configuration |
| 395 | * |
| 396 | * Run time configuration allows the application to choose between |
| 397 | * implementations of certain arithmetic APIs. The default is set |
| 398 | * at build time and recorded in pnglibconf.h, but it is safe to |
| 399 | * override these (and only these) settings. Note that this won't |
| 400 | * change what the library does, only application code, and the |
| 401 | * settings can (and probably should) be made on a per-file basis |
| 402 | * by setting the #defines before including png.h |
| 403 | * |
| 404 | * Use macros to read integers from PNG data or use the exported |
| 405 | * functions? |
| 406 | * PNG_USE_READ_MACROS: use the macros (see below) Note that |
| 407 | * the macros evaluate their argument multiple times. |
| 408 | * PNG_NO_USE_READ_MACROS: call the relevant library function. |
| 409 | * |
| 410 | * Use the alternative algorithm for compositing alpha samples that |
| 411 | * does not use division? |
| 412 | * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' |
| 413 | * algorithm. |
| 414 | * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. |
| 415 | * |
| 416 | * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is |
| 417 | * false? |
| 418 | * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error |
| 419 | * APIs to png_warning. |
| 420 | * Otherwise the calls are mapped to png_error. |
| 421 | */ |
| 422 | |
| 423 | /* Section 3: type definitions, including structures and compile time |
| 424 | * constants. |
| 425 | * See pngconf.h for base types that vary by machine/system |
| 426 | */ |
| 427 | |
| 428 | /* This triggers a compiler error in png.c, if png.c and png.h |
| 429 | * do not agree upon the version number. |
| 430 | */ |
| 431 | typedef char* png_libpng_version_1_6_38_git; |
| 432 | |
| 433 | /* Basic control structions. Read libpng-manual.txt or libpng.3 for more info. |
| 434 | * |
| 435 | * png_struct is the cache of information used while reading or writing a single |
| 436 | * PNG file. One of these is always required, although the simplified API |
| 437 | * (below) hides the creation and destruction of it. |
| 438 | */ |
| 439 | typedef struct png_struct_def png_struct; |
| 440 | typedef const png_struct * png_const_structp; |
| 441 | typedef png_struct * png_structp; |
| 442 | typedef png_struct * * png_structpp; |
| 443 | |
| 444 | /* png_info contains information read from or to be written to a PNG file. One |
| 445 | * or more of these must exist while reading or creating a PNG file. The |
| 446 | * information is not used by libpng during read but is used to control what |
| 447 | * gets written when a PNG file is created. "png_get_" function calls read |
| 448 | * information during read and "png_set_" functions calls write information |
| 449 | * when creating a PNG. |
| 450 | * been moved into a separate header file that is not accessible to |
| 451 | * applications. Read libpng-manual.txt or libpng.3 for more info. |
| 452 | */ |
| 453 | typedef struct png_info_def png_info; |
| 454 | typedef png_info * png_infop; |
| 455 | typedef const png_info * png_const_infop; |
| 456 | typedef png_info * * png_infopp; |
| 457 | |
| 458 | /* Types with names ending 'p' are pointer types. The corresponding types with |
| 459 | * names ending 'rp' are identical pointer types except that the pointer is |
| 460 | * marked 'restrict', which means that it is the only pointer to the object |
| 461 | * passed to the function. Applications should not use the 'restrict' types; |
| 462 | * it is always valid to pass 'p' to a pointer with a function argument of the |
| 463 | * corresponding 'rp' type. Different compilers have different rules with |
| 464 | * regard to type matching in the presence of 'restrict'. For backward |
| 465 | * compatibility libpng callbacks never have 'restrict' in their parameters and, |
| 466 | * consequentially, writing portable application code is extremely difficult if |
| 467 | * an attempt is made to use 'restrict'. |
| 468 | */ |
| 469 | typedef png_struct * PNG_RESTRICT png_structrp; |
| 470 | typedef const png_struct * PNG_RESTRICT png_const_structrp; |
| 471 | typedef png_info * PNG_RESTRICT png_inforp; |
| 472 | typedef const png_info * PNG_RESTRICT png_const_inforp; |
| 473 | |
| 474 | /* Three color definitions. The order of the red, green, and blue, (and the |
| 475 | * exact size) is not important, although the size of the fields need to |
| 476 | * be png_byte or png_uint_16 (as defined below). |
| 477 | */ |
| 478 | typedef struct png_color_struct |
| 479 | { |
| 480 | png_byte red; |
| 481 | png_byte green; |
| 482 | png_byte blue; |
| 483 | } png_color; |
| 484 | typedef png_color * png_colorp; |
| 485 | typedef const png_color * png_const_colorp; |
| 486 | typedef png_color * * png_colorpp; |
| 487 | |
| 488 | typedef struct png_color_16_struct |
| 489 | { |
| 490 | png_byte index; /* used for palette files */ |
| 491 | png_uint_16 red; /* for use in red green blue files */ |
| 492 | png_uint_16 green; |
| 493 | png_uint_16 blue; |
| 494 | png_uint_16 gray; /* for use in grayscale files */ |
| 495 | } png_color_16; |
| 496 | typedef png_color_16 * png_color_16p; |
| 497 | typedef const png_color_16 * png_const_color_16p; |
| 498 | typedef png_color_16 * * png_color_16pp; |
| 499 | |
| 500 | typedef struct png_color_8_struct |
| 501 | { |
| 502 | png_byte red; /* for use in red green blue files */ |
| 503 | png_byte green; |
| 504 | png_byte blue; |
| 505 | png_byte gray; /* for use in grayscale files */ |
| 506 | png_byte alpha; /* for alpha channel files */ |
| 507 | } png_color_8; |
| 508 | typedef png_color_8 * png_color_8p; |
| 509 | typedef const png_color_8 * png_const_color_8p; |
| 510 | typedef png_color_8 * * png_color_8pp; |
| 511 | |
| 512 | /* |
| 513 | * The following two structures are used for the in-core representation |
| 514 | * of sPLT chunks. |
| 515 | */ |
| 516 | typedef struct png_sPLT_entry_struct |
| 517 | { |
| 518 | png_uint_16 red; |
| 519 | png_uint_16 green; |
| 520 | png_uint_16 blue; |
| 521 | png_uint_16 alpha; |
| 522 | png_uint_16 frequency; |
| 523 | } png_sPLT_entry; |
| 524 | typedef png_sPLT_entry * png_sPLT_entryp; |
| 525 | typedef const png_sPLT_entry * png_const_sPLT_entryp; |
| 526 | typedef png_sPLT_entry * * png_sPLT_entrypp; |
| 527 | |
| 528 | /* When the depth of the sPLT palette is 8 bits, the color and alpha samples |
| 529 | * occupy the LSB of their respective members, and the MSB of each member |
| 530 | * is zero-filled. The frequency member always occupies the full 16 bits. |
| 531 | */ |
| 532 | |
| 533 | typedef struct png_sPLT_struct |
| 534 | { |
| 535 | png_charp name; /* palette name */ |
| 536 | png_byte depth; /* depth of palette samples */ |
| 537 | png_sPLT_entryp entries; /* palette entries */ |
| 538 | png_int_32 nentries; /* number of palette entries */ |
| 539 | } png_sPLT_t; |
| 540 | typedef png_sPLT_t * png_sPLT_tp; |
| 541 | typedef const png_sPLT_t * png_const_sPLT_tp; |
| 542 | typedef png_sPLT_t * * png_sPLT_tpp; |
| 543 | |
| 544 | #ifdef PNG_TEXT_SUPPORTED |
| 545 | /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, |
| 546 | * and whether that contents is compressed or not. The "key" field |
| 547 | * points to a regular zero-terminated C string. The "text" fields can be a |
| 548 | * regular C string, an empty string, or a NULL pointer. |
| 549 | * However, the structure returned by png_get_text() will always contain |
| 550 | * the "text" field as a regular zero-terminated C string (possibly |
| 551 | * empty), never a NULL pointer, so it can be safely used in printf() and |
| 552 | * other string-handling functions. Note that the "itxt_length", "lang", and |
| 553 | * "lang_key" members of the structure only exist when the library is built |
| 554 | * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by |
| 555 | * default without iTXt support. Also note that when iTXt *is* supported, |
| 556 | * the "lang" and "lang_key" fields contain NULL pointers when the |
| 557 | * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or |
| 558 | * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the |
| 559 | * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag" |
| 560 | * which is always 0 or 1, or its "compression method" which is always 0. |
| 561 | */ |
| 562 | typedef struct png_text_struct |
| 563 | { |
| 564 | int compression; /* compression value: |
| 565 | -1: tEXt, none |
| 566 | 0: zTXt, deflate |
| 567 | 1: iTXt, none |
| 568 | 2: iTXt, deflate */ |
| 569 | png_charp key; /* keyword, 1-79 character description of "text" */ |
| 570 | png_charp text; /* comment, may be an empty string (ie "") |
| 571 | or a NULL pointer */ |
| 572 | size_t text_length; /* length of the text string */ |
| 573 | size_t itxt_length; /* length of the itxt string */ |
| 574 | png_charp lang; /* language code, 0-79 characters |
| 575 | or a NULL pointer */ |
| 576 | png_charp lang_key; /* keyword translated UTF-8 string, 0 or more |
| 577 | chars or a NULL pointer */ |
| 578 | } png_text; |
| 579 | typedef png_text * png_textp; |
| 580 | typedef const png_text * png_const_textp; |
| 581 | typedef png_text * * png_textpp; |
| 582 | #endif |
| 583 | |
| 584 | /* Supported compression types for text in PNG files (tEXt, and zTXt). |
| 585 | * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ |
| 586 | #define PNG_TEXT_COMPRESSION_NONE_WR -3 |
| 587 | #define PNG_TEXT_COMPRESSION_zTXt_WR -2 |
| 588 | #define PNG_TEXT_COMPRESSION_NONE -1 |
| 589 | #define PNG_TEXT_COMPRESSION_zTXt 0 |
| 590 | #define PNG_ITXT_COMPRESSION_NONE 1 |
| 591 | #define PNG_ITXT_COMPRESSION_zTXt 2 |
| 592 | #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ |
| 593 | |
| 594 | /* png_time is a way to hold the time in an machine independent way. |
| 595 | * Two conversions are provided, both from time_t and struct tm. There |
| 596 | * is no portable way to convert to either of these structures, as far |
| 597 | * as I know. If you know of a portable way, send it to me. As a side |
| 598 | * note - PNG has always been Year 2000 compliant! |
| 599 | */ |
| 600 | typedef struct png_time_struct |
| 601 | { |
| 602 | png_uint_16 year; /* full year, as in, 1995 */ |
| 603 | png_byte month; /* month of year, 1 - 12 */ |
| 604 | png_byte day; /* day of month, 1 - 31 */ |
| 605 | png_byte hour; /* hour of day, 0 - 23 */ |
| 606 | png_byte minute; /* minute of hour, 0 - 59 */ |
| 607 | png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ |
| 608 | } png_time; |
| 609 | typedef png_time * png_timep; |
| 610 | typedef const png_time * png_const_timep; |
| 611 | typedef png_time * * png_timepp; |
| 612 | |
| 613 | #if defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) ||\ |
| 614 | defined(PNG_USER_CHUNKS_SUPPORTED) |
| 615 | /* png_unknown_chunk is a structure to hold queued chunks for which there is |
| 616 | * no specific support. The idea is that we can use this to queue |
| 617 | * up private chunks for output even though the library doesn't actually |
| 618 | * know about their semantics. |
| 619 | * |
| 620 | * The data in the structure is set by libpng on read and used on write. |
| 621 | */ |
| 622 | typedef struct png_unknown_chunk_t |
| 623 | { |
| 624 | png_byte name[5]; /* Textual chunk name with '\0' terminator */ |
| 625 | png_byte *data; /* Data, should not be modified on read! */ |
| 626 | size_t size; |
| 627 | |
| 628 | /* On write 'location' must be set using the flag values listed below. |
| 629 | * Notice that on read it is set by libpng however the values stored have |
| 630 | * more bits set than are listed below. Always treat the value as a |
| 631 | * bitmask. On write set only one bit - setting multiple bits may cause the |
| 632 | * chunk to be written in multiple places. |
| 633 | */ |
| 634 | png_byte location; /* mode of operation at read time */ |
| 635 | } |
| 636 | png_unknown_chunk; |
| 637 | |
| 638 | typedef png_unknown_chunk * png_unknown_chunkp; |
| 639 | typedef const png_unknown_chunk * png_const_unknown_chunkp; |
| 640 | typedef png_unknown_chunk * * png_unknown_chunkpp; |
| 641 | #endif |
| 642 | |
| 643 | /* Flag values for the unknown chunk location byte. */ |
| 644 | #define PNG_HAVE_IHDR 0x01 |
| 645 | #define PNG_HAVE_PLTE 0x02 |
| 646 | #define PNG_AFTER_IDAT 0x08 |
| 647 | |
| 648 | /* Maximum positive integer used in PNG is (2^31)-1 */ |
| 649 | #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) |
| 650 | #define PNG_UINT_32_MAX ((png_uint_32)(-1)) |
| 651 | #define PNG_SIZE_MAX ((size_t)(-1)) |
| 652 | |
| 653 | /* These are constants for fixed point values encoded in the |
| 654 | * PNG specification manner (x100000) |
| 655 | */ |
| 656 | #define PNG_FP_1 100000 |
| 657 | #define PNG_FP_HALF 50000 |
| 658 | #define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) |
| 659 | #define PNG_FP_MIN (-PNG_FP_MAX) |
| 660 | |
| 661 | /* These describe the color_type field in png_info. */ |
| 662 | /* color type masks */ |
| 663 | #define PNG_COLOR_MASK_PALETTE 1 |
| 664 | #define PNG_COLOR_MASK_COLOR 2 |
| 665 | #define PNG_COLOR_MASK_ALPHA 4 |
| 666 | |
| 667 | /* color types. Note that not all combinations are legal */ |
| 668 | #define PNG_COLOR_TYPE_GRAY 0 |
| 669 | #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) |
| 670 | #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) |
| 671 | #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) |
| 672 | #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) |
| 673 | /* aliases */ |
| 674 | #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA |
| 675 | #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA |
| 676 | |
| 677 | /* This is for compression type. PNG 1.0-1.2 only define the single type. */ |
| 678 | #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ |
| 679 | #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE |
| 680 | |
| 681 | /* This is for filter type. PNG 1.0-1.2 only define the single type. */ |
| 682 | #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ |
| 683 | #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ |
| 684 | #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE |
| 685 | |
| 686 | /* These are for the interlacing type. These values should NOT be changed. */ |
| 687 | #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ |
| 688 | #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ |
| 689 | #define PNG_INTERLACE_LAST 2 /* Not a valid value */ |
| 690 | |
| 691 | /* These are for the oFFs chunk. These values should NOT be changed. */ |
| 692 | #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ |
| 693 | #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ |
| 694 | #define PNG_OFFSET_LAST 2 /* Not a valid value */ |
| 695 | |
| 696 | /* These are for the pCAL chunk. These values should NOT be changed. */ |
| 697 | #define PNG_EQUATION_LINEAR 0 /* Linear transformation */ |
| 698 | #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ |
| 699 | #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ |
| 700 | #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ |
| 701 | #define PNG_EQUATION_LAST 4 /* Not a valid value */ |
| 702 | |
| 703 | /* These are for the sCAL chunk. These values should NOT be changed. */ |
| 704 | #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ |
| 705 | #define PNG_SCALE_METER 1 /* meters per pixel */ |
| 706 | #define PNG_SCALE_RADIAN 2 /* radians per pixel */ |
| 707 | #define PNG_SCALE_LAST 3 /* Not a valid value */ |
| 708 | |
| 709 | /* These are for the pHYs chunk. These values should NOT be changed. */ |
| 710 | #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ |
| 711 | #define PNG_RESOLUTION_METER 1 /* pixels/meter */ |
| 712 | #define PNG_RESOLUTION_LAST 2 /* Not a valid value */ |
| 713 | |
| 714 | /* These are for the sRGB chunk. These values should NOT be changed. */ |
| 715 | #define PNG_sRGB_INTENT_PERCEPTUAL 0 |
| 716 | #define PNG_sRGB_INTENT_RELATIVE 1 |
| 717 | #define PNG_sRGB_INTENT_SATURATION 2 |
| 718 | #define PNG_sRGB_INTENT_ABSOLUTE 3 |
| 719 | #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ |
| 720 | |
| 721 | /* This is for text chunks */ |
| 722 | #define PNG_KEYWORD_MAX_LENGTH 79 |
| 723 | |
| 724 | /* Maximum number of entries in PLTE/sPLT/tRNS arrays */ |
| 725 | #define PNG_MAX_PALETTE_LENGTH 256 |
| 726 | |
| 727 | /* These determine if an ancillary chunk's data has been successfully read |
| 728 | * from the PNG header, or if the application has filled in the corresponding |
| 729 | * data in the info_struct to be written into the output file. The values |
| 730 | * of the PNG_INFO_<chunk> defines should NOT be changed. |
| 731 | */ |
| 732 | #define PNG_INFO_gAMA 0x0001U |
| 733 | #define PNG_INFO_sBIT 0x0002U |
| 734 | #define PNG_INFO_cHRM 0x0004U |
| 735 | #define PNG_INFO_PLTE 0x0008U |
| 736 | #define PNG_INFO_tRNS 0x0010U |
| 737 | #define PNG_INFO_bKGD 0x0020U |
| 738 | #define PNG_INFO_hIST 0x0040U |
| 739 | #define PNG_INFO_pHYs 0x0080U |
| 740 | #define PNG_INFO_oFFs 0x0100U |
| 741 | #define PNG_INFO_tIME 0x0200U |
| 742 | #define PNG_INFO_pCAL 0x0400U |
| 743 | #define PNG_INFO_sRGB 0x0800U /* GR-P, 0.96a */ |
| 744 | #define PNG_INFO_iCCP 0x1000U /* ESR, 1.0.6 */ |
| 745 | #define PNG_INFO_sPLT 0x2000U /* ESR, 1.0.6 */ |
| 746 | #define PNG_INFO_sCAL 0x4000U /* ESR, 1.0.6 */ |
| 747 | #define PNG_INFO_IDAT 0x8000U /* ESR, 1.0.6 */ |
| 748 | #define PNG_INFO_eXIf 0x10000U /* GR-P, 1.6.31 */ |
| 749 | |
| 750 | /* This is used for the transformation routines, as some of them |
| 751 | * change these values for the row. It also should enable using |
| 752 | * the routines for other purposes. |
| 753 | */ |
| 754 | typedef struct png_row_info_struct |
| 755 | { |
| 756 | png_uint_32 width; /* width of row */ |
| 757 | size_t rowbytes; /* number of bytes in row */ |
| 758 | png_byte color_type; /* color type of row */ |
| 759 | png_byte bit_depth; /* bit depth of row */ |
| 760 | png_byte channels; /* number of channels (1, 2, 3, or 4) */ |
| 761 | png_byte pixel_depth; /* bits per pixel (depth * channels) */ |
| 762 | } png_row_info; |
| 763 | |
| 764 | typedef png_row_info * png_row_infop; |
| 765 | typedef png_row_info * * png_row_infopp; |
| 766 | |
| 767 | /* These are the function types for the I/O functions and for the functions |
| 768 | * that allow the user to override the default I/O functions with his or her |
| 769 | * own. The png_error_ptr type should match that of user-supplied warning |
| 770 | * and error functions, while the png_rw_ptr type should match that of the |
| 771 | * user read/write data functions. Note that the 'write' function must not |
| 772 | * modify the buffer it is passed. The 'read' function, on the other hand, is |
| 773 | * expected to return the read data in the buffer. |
| 774 | */ |
| 775 | typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); |
| 776 | typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, size_t)); |
| 777 | typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); |
| 778 | typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, |
| 779 | int)); |
| 780 | typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, |
| 781 | int)); |
| 782 | |
| 783 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
| 784 | typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); |
| 785 | typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); |
| 786 | |
| 787 | /* The following callback receives png_uint_32 row_number, int pass for the |
| 788 | * png_bytep data of the row. When transforming an interlaced image the |
| 789 | * row number is the row number within the sub-image of the interlace pass, so |
| 790 | * the value will increase to the height of the sub-image (not the full image) |
| 791 | * then reset to 0 for the next pass. |
| 792 | * |
| 793 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
| 794 | * find the output pixel (x,y) given an interlaced sub-image pixel |
| 795 | * (row,col,pass). (See below for these macros.) |
| 796 | */ |
| 797 | typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, |
| 798 | png_uint_32, int)); |
| 799 | #endif |
| 800 | |
| 801 | #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ |
| 802 | defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) |
| 803 | typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, |
| 804 | png_bytep)); |
| 805 | #endif |
| 806 | |
| 807 | #ifdef PNG_USER_CHUNKS_SUPPORTED |
| 808 | typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, |
| 809 | png_unknown_chunkp)); |
| 810 | #endif |
| 811 | #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED |
| 812 | /* not used anywhere */ |
| 813 | /* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); */ |
| 814 | #endif |
| 815 | |
| 816 | #ifdef PNG_SETJMP_SUPPORTED |
| 817 | /* This must match the function definition in <setjmp.h>, and the application |
| 818 | * must include this before png.h to obtain the definition of jmp_buf. The |
| 819 | * function is required to be PNG_NORETURN, but this is not checked. If the |
| 820 | * function does return the application will crash via an abort() or similar |
| 821 | * system level call. |
| 822 | * |
| 823 | * If you get a warning here while building the library you may need to make |
| 824 | * changes to ensure that pnglibconf.h records the calling convention used by |
| 825 | * your compiler. This may be very difficult - try using a different compiler |
| 826 | * to build the library! |
| 827 | */ |
| 828 | PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); |
| 829 | #endif |
| 830 | |
| 831 | /* Transform masks for the high-level interface */ |
| 832 | #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ |
| 833 | #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ |
| 834 | #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ |
| 835 | #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ |
| 836 | #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ |
| 837 | #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ |
| 838 | #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ |
| 839 | #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ |
| 840 | #define PNG_TRANSFORM_BGR 0x0080 /* read and write */ |
| 841 | #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ |
| 842 | #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ |
| 843 | #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ |
| 844 | #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ |
| 845 | /* Added to libpng-1.2.34 */ |
| 846 | #define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER |
| 847 | #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ |
| 848 | /* Added to libpng-1.4.0 */ |
| 849 | #define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ |
| 850 | /* Added to libpng-1.5.4 */ |
| 851 | #define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ |
| 852 | #if INT_MAX >= 0x8000 /* else this might break */ |
| 853 | #define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ |
| 854 | #endif |
| 855 | |
| 856 | /* Flags for MNG supported features */ |
| 857 | #define PNG_FLAG_MNG_EMPTY_PLTE 0x01 |
| 858 | #define PNG_FLAG_MNG_FILTER_64 0x04 |
| 859 | #define PNG_ALL_MNG_FEATURES 0x05 |
| 860 | |
| 861 | /* NOTE: prior to 1.5 these functions had no 'API' style declaration, |
| 862 | * this allowed the zlib default functions to be used on Windows |
| 863 | * platforms. In 1.5 the zlib default malloc (which just calls malloc and |
| 864 | * ignores the first argument) should be completely compatible with the |
| 865 | * following. |
| 866 | */ |
| 867 | typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, |
| 868 | png_alloc_size_t)); |
| 869 | typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); |
| 870 | |
| 871 | /* Section 4: exported functions |
| 872 | * Here are the function definitions most commonly used. This is not |
| 873 | * the place to find out how to use libpng. See libpng-manual.txt for the |
| 874 | * full explanation, see example.c for the summary. This just provides |
| 875 | * a simple one line description of the use of each function. |
| 876 | * |
| 877 | * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in |
| 878 | * pngconf.h and in the *.dfn files in the scripts directory. |
| 879 | * |
| 880 | * PNG_EXPORT(ordinal, type, name, (args)); |
| 881 | * |
| 882 | * ordinal: ordinal that is used while building |
| 883 | * *.def files. The ordinal value is only |
| 884 | * relevant when preprocessing png.h with |
| 885 | * the *.dfn files for building symbol table |
| 886 | * entries, and are removed by pngconf.h. |
| 887 | * type: return type of the function |
| 888 | * name: function name |
| 889 | * args: function arguments, with types |
| 890 | * |
| 891 | * When we wish to append attributes to a function prototype we use |
| 892 | * the PNG_EXPORTA() macro instead. |
| 893 | * |
| 894 | * PNG_EXPORTA(ordinal, type, name, (args), attributes); |
| 895 | * |
| 896 | * ordinal, type, name, and args: same as in PNG_EXPORT(). |
| 897 | * attributes: function attributes |
| 898 | */ |
| 899 | |
| 900 | /* Returns the version number of the library */ |
| 901 | PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); |
| 902 | |
| 903 | /* Tell lib we have already handled the first <num_bytes> magic bytes. |
| 904 | * Handling more than 8 bytes from the beginning of the file is an error. |
| 905 | */ |
| 906 | PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes)); |
| 907 | |
| 908 | /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a |
| 909 | * PNG file. Returns zero if the supplied bytes match the 8-byte PNG |
| 910 | * signature, and non-zero otherwise. Having num_to_check == 0 or |
| 911 | * start > 7 will always fail (ie return non-zero). |
| 912 | */ |
| 913 | PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, size_t start, |
| 914 | size_t num_to_check)); |
| 915 | |
| 916 | /* Simple signature checking function. This is the same as calling |
| 917 | * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). |
| 918 | */ |
| 919 | #define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) |
| 920 | |
| 921 | /* Allocate and initialize png_ptr struct for reading, and any other memory. */ |
| 922 | PNG_EXPORTA(4, png_structp, png_create_read_struct, |
| 923 | (png_const_charp user_png_ver, png_voidp error_ptr, |
| 924 | png_error_ptr error_fn, png_error_ptr warn_fn), |
| 925 | PNG_ALLOCATED); |
| 926 | |
| 927 | /* Allocate and initialize png_ptr struct for writing, and any other memory */ |
| 928 | PNG_EXPORTA(5, png_structp, png_create_write_struct, |
| 929 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
| 930 | png_error_ptr warn_fn), |
| 931 | PNG_ALLOCATED); |
| 932 | |
| 933 | PNG_EXPORT(6, size_t, png_get_compression_buffer_size, |
| 934 | (png_const_structrp png_ptr)); |
| 935 | |
| 936 | PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr, |
| 937 | size_t size)); |
| 938 | |
| 939 | /* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp |
| 940 | * match up. |
| 941 | */ |
| 942 | #ifdef PNG_SETJMP_SUPPORTED |
| 943 | /* This function returns the jmp_buf built in to *png_ptr. It must be |
| 944 | * supplied with an appropriate 'longjmp' function to use on that jmp_buf |
| 945 | * unless the default error function is overridden in which case NULL is |
| 946 | * acceptable. The size of the jmp_buf is checked against the actual size |
| 947 | * allocated by the library - the call will return NULL on a mismatch |
| 948 | * indicating an ABI mismatch. |
| 949 | */ |
| 950 | PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr, |
| 951 | png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); |
| 952 | # define png_jmpbuf(png_ptr) \ |
| 953 | (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf)))) |
| 954 | #else |
| 955 | # define png_jmpbuf(png_ptr) \ |
| 956 | (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) |
| 957 | #endif |
| 958 | /* This function should be used by libpng applications in place of |
| 959 | * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it |
| 960 | * will use it; otherwise it will call PNG_ABORT(). This function was |
| 961 | * added in libpng-1.5.0. |
| 962 | */ |
| 963 | PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val), |
| 964 | PNG_NORETURN); |
| 965 | |
| 966 | #ifdef PNG_READ_SUPPORTED |
| 967 | /* Reset the compression stream */ |
| 968 | PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED); |
| 969 | #endif |
| 970 | |
| 971 | /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ |
| 972 | #ifdef PNG_USER_MEM_SUPPORTED |
| 973 | PNG_EXPORTA(11, png_structp, png_create_read_struct_2, |
| 974 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
| 975 | png_error_ptr warn_fn, |
| 976 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
| 977 | PNG_ALLOCATED); |
| 978 | PNG_EXPORTA(12, png_structp, png_create_write_struct_2, |
| 979 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
| 980 | png_error_ptr warn_fn, |
| 981 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
| 982 | PNG_ALLOCATED); |
| 983 | #endif |
| 984 | |
| 985 | /* Write the PNG file signature. */ |
| 986 | PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr)); |
| 987 | |
| 988 | /* Write a PNG chunk - size, type, (optional) data, CRC. */ |
| 989 | PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep |
| 990 | chunk_name, png_const_bytep data, size_t length)); |
| 991 | |
| 992 | /* Write the start of a PNG chunk - length and chunk name. */ |
| 993 | PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr, |
| 994 | png_const_bytep chunk_name, png_uint_32 length)); |
| 995 | |
| 996 | /* Write the data of a PNG chunk started with png_write_chunk_start(). */ |
| 997 | PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr, |
| 998 | png_const_bytep data, size_t length)); |
| 999 | |
| 1000 | /* Finish a chunk started with png_write_chunk_start() (includes CRC). */ |
| 1001 | PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr)); |
| 1002 | |
| 1003 | /* Allocate and initialize the info structure */ |
| 1004 | PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr), |
| 1005 | PNG_ALLOCATED); |
| 1006 | |
| 1007 | /* DEPRECATED: this function allowed init structures to be created using the |
| 1008 | * default allocation method (typically malloc). Use is deprecated in 1.6.0 and |
| 1009 | * the API will be removed in the future. |
| 1010 | */ |
| 1011 | PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr, |
| 1012 | size_t png_info_struct_size), PNG_DEPRECATED); |
| 1013 | |
| 1014 | /* Writes all the PNG information before the image. */ |
| 1015 | PNG_EXPORT(20, void, png_write_info_before_PLTE, |
| 1016 | (png_structrp png_ptr, png_const_inforp info_ptr)); |
| 1017 | PNG_EXPORT(21, void, png_write_info, |
| 1018 | (png_structrp png_ptr, png_const_inforp info_ptr)); |
| 1019 | |
| 1020 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
| 1021 | /* Read the information before the actual image data. */ |
| 1022 | PNG_EXPORT(22, void, png_read_info, |
| 1023 | (png_structrp png_ptr, png_inforp info_ptr)); |
| 1024 | #endif |
| 1025 | |
| 1026 | #ifdef PNG_TIME_RFC1123_SUPPORTED |
| 1027 | /* Convert to a US string format: there is no localization support in this |
| 1028 | * routine. The original implementation used a 29 character buffer in |
| 1029 | * png_struct, this will be removed in future versions. |
| 1030 | */ |
| 1031 | #if PNG_LIBPNG_VER < 10700 |
| 1032 | /* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */ |
| 1033 | PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr, |
| 1034 | png_const_timep ptime),PNG_DEPRECATED); |
| 1035 | #endif |
| 1036 | PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29], |
| 1037 | png_const_timep ptime)); |
| 1038 | #endif |
| 1039 | |
| 1040 | #ifdef PNG_CONVERT_tIME_SUPPORTED |
| 1041 | /* Convert from a struct tm to png_time */ |
| 1042 | PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, |
| 1043 | const struct tm * ttime)); |
| 1044 | |
| 1045 | /* Convert from time_t to png_time. Uses gmtime() */ |
| 1046 | PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime)); |
| 1047 | #endif /* CONVERT_tIME */ |
| 1048 | |
| 1049 | #ifdef PNG_READ_EXPAND_SUPPORTED |
| 1050 | /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ |
| 1051 | PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr)); |
| 1052 | PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr)); |
| 1053 | PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr)); |
| 1054 | PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr)); |
| 1055 | #endif |
| 1056 | |
| 1057 | #ifdef PNG_READ_EXPAND_16_SUPPORTED |
| 1058 | /* Expand to 16-bit channels, forces conversion of palette to RGB and expansion |
| 1059 | * of a tRNS chunk if present. |
| 1060 | */ |
| 1061 | PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr)); |
| 1062 | #endif |
| 1063 | |
| 1064 | #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
| 1065 | /* Use blue, green, red order for pixels. */ |
| 1066 | PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr)); |
| 1067 | #endif |
| 1068 | |
| 1069 | #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED |
| 1070 | /* Expand the grayscale to 24-bit RGB if necessary. */ |
| 1071 | PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr)); |
| 1072 | #endif |
| 1073 | |
| 1074 | #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED |
| 1075 | /* Reduce RGB to grayscale. */ |
| 1076 | #define PNG_ERROR_ACTION_NONE 1 |
| 1077 | #define PNG_ERROR_ACTION_WARN 2 |
| 1078 | #define PNG_ERROR_ACTION_ERROR 3 |
| 1079 | #define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ |
| 1080 | |
| 1081 | PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr, |
| 1082 | int error_action, double red, double green)) |
| 1083 | PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr, |
| 1084 | int error_action, png_fixed_point red, png_fixed_point green)) |
| 1085 | |
| 1086 | PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp |
| 1087 | png_ptr)); |
| 1088 | #endif |
| 1089 | |
| 1090 | #ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED |
| 1091 | PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, |
| 1092 | png_colorp palette)); |
| 1093 | #endif |
| 1094 | |
| 1095 | #ifdef PNG_READ_ALPHA_MODE_SUPPORTED |
| 1096 | /* How the alpha channel is interpreted - this affects how the color channels |
| 1097 | * of a PNG file are returned to the calling application when an alpha channel, |
| 1098 | * or a tRNS chunk in a palette file, is present. |
| 1099 | * |
| 1100 | * This has no effect on the way pixels are written into a PNG output |
| 1101 | * datastream. The color samples in a PNG datastream are never premultiplied |
| 1102 | * with the alpha samples. |
| 1103 | * |
| 1104 | * The default is to return data according to the PNG specification: the alpha |
| 1105 | * channel is a linear measure of the contribution of the pixel to the |
| 1106 | * corresponding composited pixel, and the color channels are unassociated |
| 1107 | * (not premultiplied). The gamma encoded color channels must be scaled |
| 1108 | * according to the contribution and to do this it is necessary to undo |
| 1109 | * the encoding, scale the color values, perform the composition and re-encode |
| 1110 | * the values. This is the 'PNG' mode. |
| 1111 | * |
| 1112 | * The alternative is to 'associate' the alpha with the color information by |
| 1113 | * storing color channel values that have been scaled by the alpha. |
| 1114 | * image. These are the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' modes |
| 1115 | * (the latter being the two common names for associated alpha color channels). |
| 1116 | * |
| 1117 | * For the 'OPTIMIZED' mode, a pixel is treated as opaque only if the alpha |
| 1118 | * value is equal to the maximum value. |
| 1119 | * |
| 1120 | * The final choice is to gamma encode the alpha channel as well. This is |
| 1121 | * broken because, in practice, no implementation that uses this choice |
| 1122 | * correctly undoes the encoding before handling alpha composition. Use this |
| 1123 | * choice only if other serious errors in the software or hardware you use |
| 1124 | * mandate it; the typical serious error is for dark halos to appear around |
| 1125 | * opaque areas of the composited PNG image because of arithmetic overflow. |
| 1126 | * |
| 1127 | * The API function png_set_alpha_mode specifies which of these choices to use |
| 1128 | * with an enumerated 'mode' value and the gamma of the required output: |
| 1129 | */ |
| 1130 | #define PNG_ALPHA_PNG 0 /* according to the PNG standard */ |
| 1131 | #define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ |
| 1132 | #define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ |
| 1133 | #define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ |
| 1134 | #define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ |
| 1135 | #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ |
| 1136 | |
| 1137 | PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode, |
| 1138 | double output_gamma)) |
| 1139 | PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr, |
| 1140 | int mode, png_fixed_point output_gamma)) |
| 1141 | #endif |
| 1142 | |
| 1143 | #if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) |
| 1144 | /* The output_gamma value is a screen gamma in libpng terminology: it expresses |
| 1145 | * how to decode the output values, not how they are encoded. |
| 1146 | */ |
| 1147 | #define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ |
| 1148 | #define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ |
| 1149 | #define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ |
| 1150 | #define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ |
| 1151 | #endif |
| 1152 | |
| 1153 | /* The following are examples of calls to png_set_alpha_mode to achieve the |
| 1154 | * required overall gamma correction and, where necessary, alpha |
| 1155 | * premultiplication. |
| 1156 | * |
| 1157 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
| 1158 | * This is the default libpng handling of the alpha channel - it is not |
| 1159 | * pre-multiplied into the color components. In addition the call states |
| 1160 | * that the output is for a sRGB system and causes all PNG files without gAMA |
| 1161 | * chunks to be assumed to be encoded using sRGB. |
| 1162 | * |
| 1163 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
| 1164 | * In this case the output is assumed to be something like an sRGB conformant |
| 1165 | * display preceded by a power-law lookup table of power 1.45. This is how |
| 1166 | * early Mac systems behaved. |
| 1167 | * |
| 1168 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); |
| 1169 | * This is the classic Jim Blinn approach and will work in academic |
| 1170 | * environments where everything is done by the book. It has the shortcoming |
| 1171 | * of assuming that input PNG data with no gamma information is linear - this |
| 1172 | * is unlikely to be correct unless the PNG files where generated locally. |
| 1173 | * Most of the time the output precision will be so low as to show |
| 1174 | * significant banding in dark areas of the image. |
| 1175 | * |
| 1176 | * png_set_expand_16(pp); |
| 1177 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); |
| 1178 | * This is a somewhat more realistic Jim Blinn inspired approach. PNG files |
| 1179 | * are assumed to have the sRGB encoding if not marked with a gamma value and |
| 1180 | * the output is always 16 bits per component. This permits accurate scaling |
| 1181 | * and processing of the data. If you know that your input PNG files were |
| 1182 | * generated locally you might need to replace PNG_DEFAULT_sRGB with the |
| 1183 | * correct value for your system. |
| 1184 | * |
| 1185 | * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); |
| 1186 | * If you just need to composite the PNG image onto an existing background |
| 1187 | * and if you control the code that does this you can use the optimization |
| 1188 | * setting. In this case you just copy completely opaque pixels to the |
| 1189 | * output. For pixels that are not completely transparent (you just skip |
| 1190 | * those) you do the composition math using png_composite or png_composite_16 |
| 1191 | * below then encode the resultant 8-bit or 16-bit values to match the output |
| 1192 | * encoding. |
| 1193 | * |
| 1194 | * Other cases |
| 1195 | * If neither the PNG nor the standard linear encoding work for you because |
| 1196 | * of the software or hardware you use then you have a big problem. The PNG |
| 1197 | * case will probably result in halos around the image. The linear encoding |
| 1198 | * will probably result in a washed out, too bright, image (it's actually too |
| 1199 | * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably |
| 1200 | * substantially reduce the halos. Alternatively try: |
| 1201 | * |
| 1202 | * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); |
| 1203 | * This option will also reduce the halos, but there will be slight dark |
| 1204 | * halos round the opaque parts of the image where the background is light. |
| 1205 | * In the OPTIMIZED mode the halos will be light halos where the background |
| 1206 | * is dark. Take your pick - the halos are unavoidable unless you can get |
| 1207 | * your hardware/software fixed! (The OPTIMIZED approach is slightly |
| 1208 | * faster.) |
| 1209 | * |
| 1210 | * When the default gamma of PNG files doesn't match the output gamma. |
| 1211 | * If you have PNG files with no gamma information png_set_alpha_mode allows |
| 1212 | * you to provide a default gamma, but it also sets the output gamma to the |
| 1213 | * matching value. If you know your PNG files have a gamma that doesn't |
| 1214 | * match the output you can take advantage of the fact that |
| 1215 | * png_set_alpha_mode always sets the output gamma but only sets the PNG |
| 1216 | * default if it is not already set: |
| 1217 | * |
| 1218 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
| 1219 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
| 1220 | * The first call sets both the default and the output gamma values, the |
| 1221 | * second call overrides the output gamma without changing the default. This |
| 1222 | * is easier than achieving the same effect with png_set_gamma. You must use |
| 1223 | * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will |
| 1224 | * fire if more than one call to png_set_alpha_mode and png_set_background is |
| 1225 | * made in the same read operation, however multiple calls with PNG_ALPHA_PNG |
| 1226 | * are ignored. |
| 1227 | */ |
| 1228 | |
| 1229 | #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED |
| 1230 | PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr)); |
| 1231 | #endif |
| 1232 | |
| 1233 | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ |
| 1234 | defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
| 1235 | PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr)); |
| 1236 | #endif |
| 1237 | |
| 1238 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ |
| 1239 | defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
| 1240 | PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr)); |
| 1241 | #endif |
| 1242 | |
| 1243 | #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) |
| 1244 | /* Add a filler byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */ |
| 1245 | PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler, |
| 1246 | int flags)); |
| 1247 | /* The values of the PNG_FILLER_ defines should NOT be changed */ |
| 1248 | # define PNG_FILLER_BEFORE 0 |
| 1249 | # define PNG_FILLER_AFTER 1 |
| 1250 | /* Add an alpha byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */ |
| 1251 | PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr, |
| 1252 | png_uint_32 filler, int flags)); |
| 1253 | #endif /* READ_FILLER || WRITE_FILLER */ |
| 1254 | |
| 1255 | #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
| 1256 | /* Swap bytes in 16-bit depth files. */ |
| 1257 | PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr)); |
| 1258 | #endif |
| 1259 | |
| 1260 | #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) |
| 1261 | /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ |
| 1262 | PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr)); |
| 1263 | #endif |
| 1264 | |
| 1265 | #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ |
| 1266 | defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
| 1267 | /* Swap packing order of pixels in bytes. */ |
| 1268 | PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr)); |
| 1269 | #endif |
| 1270 | |
| 1271 | #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) |
| 1272 | /* Converts files to legal bit depths. */ |
| 1273 | PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p |
| 1274 | true_bits)); |
| 1275 | #endif |
| 1276 | |
| 1277 | #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ |
| 1278 | defined(PNG_WRITE_INTERLACING_SUPPORTED) |
| 1279 | /* Have the code handle the interlacing. Returns the number of passes. |
| 1280 | * MUST be called before png_read_update_info or png_start_read_image, |
| 1281 | * otherwise it will not have the desired effect. Note that it is still |
| 1282 | * necessary to call png_read_row or png_read_rows png_get_image_height |
| 1283 | * times for each pass. |
| 1284 | */ |
| 1285 | PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr)); |
| 1286 | #endif |
| 1287 | |
| 1288 | #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) |
| 1289 | /* Invert monochrome files */ |
| 1290 | PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr)); |
| 1291 | #endif |
| 1292 | |
| 1293 | #ifdef PNG_READ_BACKGROUND_SUPPORTED |
| 1294 | /* Handle alpha and tRNS by replacing with a background color. Prior to |
| 1295 | * libpng-1.5.4 this API must not be called before the PNG file header has been |
| 1296 | * read. Doing so will result in unexpected behavior and possible warnings or |
| 1297 | * errors if the PNG file contains a bKGD chunk. |
| 1298 | */ |
| 1299 | PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr, |
| 1300 | png_const_color_16p background_color, int background_gamma_code, |
| 1301 | int need_expand, double background_gamma)) |
| 1302 | PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr, |
| 1303 | png_const_color_16p background_color, int background_gamma_code, |
| 1304 | int need_expand, png_fixed_point background_gamma)) |
| 1305 | #endif |
| 1306 | #ifdef PNG_READ_BACKGROUND_SUPPORTED |
| 1307 | # define PNG_BACKGROUND_GAMMA_UNKNOWN 0 |
| 1308 | # define PNG_BACKGROUND_GAMMA_SCREEN 1 |
| 1309 | # define PNG_BACKGROUND_GAMMA_FILE 2 |
| 1310 | # define PNG_BACKGROUND_GAMMA_UNIQUE 3 |
| 1311 | #endif |
| 1312 | |
| 1313 | #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED |
| 1314 | /* Scale a 16-bit depth file down to 8-bit, accurately. */ |
| 1315 | PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr)); |
| 1316 | #endif |
| 1317 | |
| 1318 | #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED |
| 1319 | #define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */ |
| 1320 | /* Strip the second byte of information from a 16-bit depth file. */ |
| 1321 | PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr)); |
| 1322 | #endif |
| 1323 | |
| 1324 | #ifdef PNG_READ_QUANTIZE_SUPPORTED |
| 1325 | /* Turn on quantizing, and reduce the palette to the number of colors |
| 1326 | * available. |
| 1327 | */ |
| 1328 | PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr, |
| 1329 | png_colorp palette, int num_palette, int maximum_colors, |
| 1330 | png_const_uint_16p histogram, int full_quantize)); |
| 1331 | #endif |
| 1332 | |
| 1333 | #ifdef PNG_READ_GAMMA_SUPPORTED |
| 1334 | /* The threshold on gamma processing is configurable but hard-wired into the |
| 1335 | * library. The following is the floating point variant. |
| 1336 | */ |
| 1337 | #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) |
| 1338 | |
| 1339 | /* Handle gamma correction. Screen_gamma=(display_exponent). |
| 1340 | * NOTE: this API simply sets the screen and file gamma values. It will |
| 1341 | * therefore override the value for gamma in a PNG file if it is called after |
| 1342 | * the file header has been read - use with care - call before reading the PNG |
| 1343 | * file for best results! |
| 1344 | * |
| 1345 | * These routines accept the same gamma values as png_set_alpha_mode (described |
| 1346 | * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either |
| 1347 | * API (floating point or fixed.) Notice, however, that the 'file_gamma' value |
| 1348 | * is the inverse of a 'screen gamma' value. |
| 1349 | */ |
| 1350 | PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr, |
| 1351 | double screen_gamma, double override_file_gamma)) |
| 1352 | PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr, |
| 1353 | png_fixed_point screen_gamma, png_fixed_point override_file_gamma)) |
| 1354 | #endif |
| 1355 | |
| 1356 | #ifdef PNG_WRITE_FLUSH_SUPPORTED |
| 1357 | /* Set how many lines between output flushes - 0 for no flushing */ |
| 1358 | PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows)); |
| 1359 | /* Flush the current PNG output buffer */ |
| 1360 | PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr)); |
| 1361 | #endif |
| 1362 | |
| 1363 | /* Optional update palette with requested transformations */ |
| 1364 | PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr)); |
| 1365 | |
| 1366 | /* Optional call to update the users info structure */ |
| 1367 | PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr, |
| 1368 | png_inforp info_ptr)); |
| 1369 | |
| 1370 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
| 1371 | /* Read one or more rows of image data. */ |
| 1372 | PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row, |
| 1373 | png_bytepp display_row, png_uint_32 num_rows)); |
| 1374 | #endif |
| 1375 | |
| 1376 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
| 1377 | /* Read a row of data. */ |
| 1378 | PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row, |
| 1379 | png_bytep display_row)); |
| 1380 | #endif |
| 1381 | |
| 1382 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
| 1383 | /* Read the whole image into memory at once. */ |
| 1384 | PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image)); |
| 1385 | #endif |
| 1386 | |
| 1387 | /* Write a row of image data */ |
| 1388 | PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr, |
| 1389 | png_const_bytep row)); |
| 1390 | |
| 1391 | /* Write a few rows of image data: (*row) is not written; however, the type |
| 1392 | * is declared as writeable to maintain compatibility with previous versions |
| 1393 | * of libpng and to allow the 'display_row' array from read_rows to be passed |
| 1394 | * unchanged to write_rows. |
| 1395 | */ |
| 1396 | PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row, |
| 1397 | png_uint_32 num_rows)); |
| 1398 | |
| 1399 | /* Write the image data */ |
| 1400 | PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image)); |
| 1401 | |
| 1402 | /* Write the end of the PNG file. */ |
| 1403 | PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr, |
| 1404 | png_inforp info_ptr)); |
| 1405 | |
| 1406 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
| 1407 | /* Read the end of the PNG file. */ |
| 1408 | PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr)); |
| 1409 | #endif |
| 1410 | |
| 1411 | /* Free any memory associated with the png_info_struct */ |
| 1412 | PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr, |
| 1413 | png_infopp info_ptr_ptr)); |
| 1414 | |
| 1415 | /* Free any memory associated with the png_struct and the png_info_structs */ |
| 1416 | PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, |
| 1417 | png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); |
| 1418 | |
| 1419 | /* Free any memory associated with the png_struct and the png_info_structs */ |
| 1420 | PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, |
| 1421 | png_infopp info_ptr_ptr)); |
| 1422 | |
| 1423 | /* Set the libpng method of handling chunk CRC errors */ |
| 1424 | PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action, |
| 1425 | int ancil_action)); |
| 1426 | |
| 1427 | /* Values for png_set_crc_action() say how to handle CRC errors in |
| 1428 | * ancillary and critical chunks, and whether to use the data contained |
| 1429 | * therein. Note that it is impossible to "discard" data in a critical |
| 1430 | * chunk. For versions prior to 0.90, the action was always error/quit, |
| 1431 | * whereas in version 0.90 and later, the action for CRC errors in ancillary |
| 1432 | * chunks is warn/discard. These values should NOT be changed. |
| 1433 | * |
| 1434 | * value action:critical action:ancillary |
| 1435 | */ |
| 1436 | #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ |
| 1437 | #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ |
| 1438 | #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ |
| 1439 | #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ |
| 1440 | #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ |
| 1441 | #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ |
| 1442 | |
| 1443 | #ifdef PNG_WRITE_SUPPORTED |
| 1444 | /* These functions give the user control over the scan-line filtering in |
| 1445 | * libpng and the compression methods used by zlib. These functions are |
| 1446 | * mainly useful for testing, as the defaults should work with most users. |
| 1447 | * Those users who are tight on memory or want faster performance at the |
| 1448 | * expense of compression can modify them. See the compression library |
| 1449 | * header file (zlib.h) for an explination of the compression functions. |
| 1450 | */ |
| 1451 | |
| 1452 | /* Set the filtering method(s) used by libpng. Currently, the only valid |
| 1453 | * value for "method" is 0. |
| 1454 | */ |
| 1455 | PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method, |
| 1456 | int filters)); |
| 1457 | #endif /* WRITE */ |
| 1458 | |
| 1459 | /* Flags for png_set_filter() to say which filters to use. The flags |
| 1460 | * are chosen so that they don't conflict with real filter types |
| 1461 | * below, in case they are supplied instead of the #defined constants. |
| 1462 | * These values should NOT be changed. |
| 1463 | */ |
| 1464 | #define PNG_NO_FILTERS 0x00 |
| 1465 | #define PNG_FILTER_NONE 0x08 |
| 1466 | #define PNG_FILTER_SUB 0x10 |
| 1467 | #define PNG_FILTER_UP 0x20 |
| 1468 | #define PNG_FILTER_AVG 0x40 |
| 1469 | #define PNG_FILTER_PAETH 0x80 |
| 1470 | #define PNG_FAST_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP) |
| 1471 | #define PNG_ALL_FILTERS (PNG_FAST_FILTERS | PNG_FILTER_AVG | PNG_FILTER_PAETH) |
| 1472 | |
| 1473 | /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. |
| 1474 | * These defines should NOT be changed. |
| 1475 | */ |
| 1476 | #define PNG_FILTER_VALUE_NONE 0 |
| 1477 | #define PNG_FILTER_VALUE_SUB 1 |
| 1478 | #define PNG_FILTER_VALUE_UP 2 |
| 1479 | #define PNG_FILTER_VALUE_AVG 3 |
| 1480 | #define PNG_FILTER_VALUE_PAETH 4 |
| 1481 | #define PNG_FILTER_VALUE_LAST 5 |
| 1482 | |
| 1483 | #ifdef PNG_WRITE_SUPPORTED |
| 1484 | #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* DEPRECATED */ |
| 1485 | PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr, |
| 1486 | int heuristic_method, int num_weights, png_const_doublep filter_weights, |
| 1487 | png_const_doublep filter_costs)) |
| 1488 | PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, |
| 1489 | (png_structrp png_ptr, int heuristic_method, int num_weights, |
| 1490 | png_const_fixed_point_p filter_weights, |
| 1491 | png_const_fixed_point_p filter_costs)) |
| 1492 | #endif /* WRITE_WEIGHTED_FILTER */ |
| 1493 | |
| 1494 | /* The following are no longer used and will be removed from libpng-1.7: */ |
| 1495 | #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ |
| 1496 | #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ |
| 1497 | #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ |
| 1498 | #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ |
| 1499 | |
| 1500 | /* Set the library compression level. Currently, valid values range from |
| 1501 | * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 |
| 1502 | * (0 - no compression, 9 - "maximal" compression). Note that tests have |
| 1503 | * shown that zlib compression levels 3-6 usually perform as well as level 9 |
| 1504 | * for PNG images, and do considerably fewer caclulations. In the future, |
| 1505 | * these values may not correspond directly to the zlib compression levels. |
| 1506 | */ |
| 1507 | #ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED |
| 1508 | PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr, |
| 1509 | int level)); |
| 1510 | |
| 1511 | PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr, |
| 1512 | int mem_level)); |
| 1513 | |
| 1514 | PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr, |
| 1515 | int strategy)); |
| 1516 | |
| 1517 | /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
| 1518 | * smaller value of window_bits if it can do so safely. |
| 1519 | */ |
| 1520 | PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr, |
| 1521 | int window_bits)); |
| 1522 | |
| 1523 | PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr, |
| 1524 | int method)); |
| 1525 | #endif /* WRITE_CUSTOMIZE_COMPRESSION */ |
| 1526 | |
| 1527 | #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED |
| 1528 | /* Also set zlib parameters for compressing non-IDAT chunks */ |
| 1529 | PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr, |
| 1530 | int level)); |
| 1531 | |
| 1532 | PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr, |
| 1533 | int mem_level)); |
| 1534 | |
| 1535 | PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr, |
| 1536 | int strategy)); |
| 1537 | |
| 1538 | /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
| 1539 | * smaller value of window_bits if it can do so safely. |
| 1540 | */ |
| 1541 | PNG_EXPORT(225, void, png_set_text_compression_window_bits, |
| 1542 | (png_structrp png_ptr, int window_bits)); |
| 1543 | |
| 1544 | PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr, |
| 1545 | int method)); |
| 1546 | #endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */ |
| 1547 | #endif /* WRITE */ |
| 1548 | |
| 1549 | /* These next functions are called for input/output, memory, and error |
| 1550 | * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, |
| 1551 | * and call standard C I/O routines such as fread(), fwrite(), and |
| 1552 | * fprintf(). These functions can be made to use other I/O routines |
| 1553 | * at run time for those applications that need to handle I/O in a |
| 1554 | * different manner by calling png_set_???_fn(). See libpng-manual.txt for |
| 1555 | * more information. |
| 1556 | */ |
| 1557 | |
| 1558 | #ifdef PNG_STDIO_SUPPORTED |
| 1559 | /* Initialize the input/output for the PNG file to the default functions. */ |
| 1560 | PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp)); |
| 1561 | #endif |
| 1562 | |
| 1563 | /* Replace the (error and abort), and warning functions with user |
| 1564 | * supplied functions. If no messages are to be printed you must still |
| 1565 | * write and use replacement functions. The replacement error_fn should |
| 1566 | * still do a longjmp to the last setjmp location if you are using this |
| 1567 | * method of error handling. If error_fn or warning_fn is NULL, the |
| 1568 | * default function will be used. |
| 1569 | */ |
| 1570 | |
| 1571 | PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr, |
| 1572 | png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); |
| 1573 | |
| 1574 | /* Return the user pointer associated with the error functions */ |
| 1575 | PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr)); |
| 1576 | |
| 1577 | /* Replace the default data output functions with a user supplied one(s). |
| 1578 | * If buffered output is not used, then output_flush_fn can be set to NULL. |
| 1579 | * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time |
| 1580 | * output_flush_fn will be ignored (and thus can be NULL). |
| 1581 | * It is probably a mistake to use NULL for output_flush_fn if |
| 1582 | * write_data_fn is not also NULL unless you have built libpng with |
| 1583 | * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's |
| 1584 | * default flush function, which uses the standard *FILE structure, will |
| 1585 | * be used. |
| 1586 | */ |
| 1587 | PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr, |
| 1588 | png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); |
| 1589 | |
| 1590 | /* Replace the default data input function with a user supplied one. */ |
| 1591 | PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr, |
| 1592 | png_rw_ptr read_data_fn)); |
| 1593 | |
| 1594 | /* Return the user pointer associated with the I/O functions */ |
| 1595 | PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr)); |
| 1596 | |
| 1597 | PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr, |
| 1598 | png_read_status_ptr read_row_fn)); |
| 1599 | |
| 1600 | PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr, |
| 1601 | png_write_status_ptr write_row_fn)); |
| 1602 | |
| 1603 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1604 | /* Replace the default memory allocation functions with user supplied one(s). */ |
| 1605 | PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr, |
| 1606 | png_malloc_ptr malloc_fn, png_free_ptr free_fn)); |
| 1607 | /* Return the user pointer associated with the memory functions */ |
| 1608 | PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr)); |
| 1609 | #endif |
| 1610 | |
| 1611 | #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED |
| 1612 | PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr, |
| 1613 | png_user_transform_ptr read_user_transform_fn)); |
| 1614 | #endif |
| 1615 | |
| 1616 | #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED |
| 1617 | PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr, |
| 1618 | png_user_transform_ptr write_user_transform_fn)); |
| 1619 | #endif |
| 1620 | |
| 1621 | #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED |
| 1622 | PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr, |
| 1623 | png_voidp user_transform_ptr, int user_transform_depth, |
| 1624 | int user_transform_channels)); |
| 1625 | /* Return the user pointer associated with the user transform functions */ |
| 1626 | PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, |
| 1627 | (png_const_structrp png_ptr)); |
| 1628 | #endif |
| 1629 | |
| 1630 | #ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED |
| 1631 | /* Return information about the row currently being processed. Note that these |
| 1632 | * APIs do not fail but will return unexpected results if called outside a user |
| 1633 | * transform callback. Also note that when transforming an interlaced image the |
| 1634 | * row number is the row number within the sub-image of the interlace pass, so |
| 1635 | * the value will increase to the height of the sub-image (not the full image) |
| 1636 | * then reset to 0 for the next pass. |
| 1637 | * |
| 1638 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
| 1639 | * find the output pixel (x,y) given an interlaced sub-image pixel |
| 1640 | * (row,col,pass). (See below for these macros.) |
| 1641 | */ |
| 1642 | PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp)); |
| 1643 | PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp)); |
| 1644 | #endif |
| 1645 | |
| 1646 | #ifdef PNG_READ_USER_CHUNKS_SUPPORTED |
| 1647 | /* This callback is called only for *unknown* chunks. If |
| 1648 | * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known |
| 1649 | * chunks to be treated as unknown, however in this case the callback must do |
| 1650 | * any processing required by the chunk (e.g. by calling the appropriate |
| 1651 | * png_set_ APIs.) |
| 1652 | * |
| 1653 | * There is no write support - on write, by default, all the chunks in the |
| 1654 | * 'unknown' list are written in the specified position. |
| 1655 | * |
| 1656 | * The integer return from the callback function is interpreted thus: |
| 1657 | * |
| 1658 | * negative: An error occurred; png_chunk_error will be called. |
| 1659 | * zero: The chunk was not handled, the chunk will be saved. A critical |
| 1660 | * chunk will cause an error at this point unless it is to be saved. |
| 1661 | * positive: The chunk was handled, libpng will ignore/discard it. |
| 1662 | * |
| 1663 | * See "INTERACTION WITH USER CHUNK CALLBACKS" below for important notes about |
| 1664 | * how this behavior will change in libpng 1.7 |
| 1665 | */ |
| 1666 | PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr, |
| 1667 | png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); |
| 1668 | #endif |
| 1669 | |
| 1670 | #ifdef PNG_USER_CHUNKS_SUPPORTED |
| 1671 | PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr)); |
| 1672 | #endif |
| 1673 | |
| 1674 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
| 1675 | /* Sets the function callbacks for the push reader, and a pointer to a |
| 1676 | * user-defined structure available to the callback functions. |
| 1677 | */ |
| 1678 | PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr, |
| 1679 | png_voidp progressive_ptr, png_progressive_info_ptr info_fn, |
| 1680 | png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); |
| 1681 | |
| 1682 | /* Returns the user pointer associated with the push read functions */ |
| 1683 | PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, |
| 1684 | (png_const_structrp png_ptr)); |
| 1685 | |
| 1686 | /* Function to be called when data becomes available */ |
| 1687 | PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr, |
| 1688 | png_inforp info_ptr, png_bytep buffer, size_t buffer_size)); |
| 1689 | |
| 1690 | /* A function which may be called *only* within png_process_data to stop the |
| 1691 | * processing of any more data. The function returns the number of bytes |
| 1692 | * remaining, excluding any that libpng has cached internally. A subsequent |
| 1693 | * call to png_process_data must supply these bytes again. If the argument |
| 1694 | * 'save' is set to true the routine will first save all the pending data and |
| 1695 | * will always return 0. |
| 1696 | */ |
| 1697 | PNG_EXPORT(219, size_t, png_process_data_pause, (png_structrp, int save)); |
| 1698 | |
| 1699 | /* A function which may be called *only* outside (after) a call to |
| 1700 | * png_process_data. It returns the number of bytes of data to skip in the |
| 1701 | * input. Normally it will return 0, but if it returns a non-zero value the |
| 1702 | * application must skip than number of bytes of input data and pass the |
| 1703 | * following data to the next call to png_process_data. |
| 1704 | */ |
| 1705 | PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp)); |
| 1706 | |
| 1707 | /* Function that combines rows. 'new_row' is a flag that should come from |
| 1708 | * the callback and be non-NULL if anything needs to be done; the library |
| 1709 | * stores its own version of the new data internally and ignores the passed |
| 1710 | * in value. |
| 1711 | */ |
| 1712 | PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr, |
| 1713 | png_bytep old_row, png_const_bytep new_row)); |
| 1714 | #endif /* PROGRESSIVE_READ */ |
| 1715 | |
| 1716 | PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr, |
| 1717 | png_alloc_size_t size), PNG_ALLOCATED); |
| 1718 | /* Added at libpng version 1.4.0 */ |
| 1719 | PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr, |
| 1720 | png_alloc_size_t size), PNG_ALLOCATED); |
| 1721 | |
| 1722 | /* Added at libpng version 1.2.4 */ |
| 1723 | PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr, |
| 1724 | png_alloc_size_t size), PNG_ALLOCATED); |
| 1725 | |
| 1726 | /* Frees a pointer allocated by png_malloc() */ |
| 1727 | PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr)); |
| 1728 | |
| 1729 | /* Free data that was allocated internally */ |
| 1730 | PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr, |
| 1731 | png_inforp info_ptr, png_uint_32 free_me, int num)); |
| 1732 | |
| 1733 | /* Reassign responsibility for freeing existing data, whether allocated |
| 1734 | * by libpng or by the application; this works on the png_info structure passed |
| 1735 | * in, it does not change the state for other png_info structures. |
| 1736 | * |
| 1737 | * It is unlikely that this function works correctly as of 1.6.0 and using it |
| 1738 | * may result either in memory leaks or double free of allocated data. |
| 1739 | */ |
| 1740 | PNG_EXPORT(99, void, png_data_freer, (png_const_structrp png_ptr, |
| 1741 | png_inforp info_ptr, int freer, png_uint_32 mask)); |
| 1742 | |
| 1743 | /* Assignments for png_data_freer */ |
| 1744 | #define PNG_DESTROY_WILL_FREE_DATA 1 |
| 1745 | #define PNG_SET_WILL_FREE_DATA 1 |
| 1746 | #define PNG_USER_WILL_FREE_DATA 2 |
| 1747 | /* Flags for png_ptr->free_me and info_ptr->free_me */ |
| 1748 | #define PNG_FREE_HIST 0x0008U |
| 1749 | #define PNG_FREE_ICCP 0x0010U |
| 1750 | #define PNG_FREE_SPLT 0x0020U |
| 1751 | #define PNG_FREE_ROWS 0x0040U |
| 1752 | #define PNG_FREE_PCAL 0x0080U |
| 1753 | #define PNG_FREE_SCAL 0x0100U |
| 1754 | #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED |
| 1755 | # define PNG_FREE_UNKN 0x0200U |
| 1756 | #endif |
| 1757 | /* PNG_FREE_LIST 0x0400U removed in 1.6.0 because it is ignored */ |
| 1758 | #define PNG_FREE_PLTE 0x1000U |
| 1759 | #define PNG_FREE_TRNS 0x2000U |
| 1760 | #define PNG_FREE_TEXT 0x4000U |
| 1761 | #define PNG_FREE_EXIF 0x8000U /* Added at libpng-1.6.31 */ |
| 1762 | #define PNG_FREE_ALL 0xffffU |
| 1763 | #define PNG_FREE_MUL 0x4220U /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ |
| 1764 | |
| 1765 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1766 | PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr, |
| 1767 | png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED); |
| 1768 | PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr, |
| 1769 | png_voidp ptr), PNG_DEPRECATED); |
| 1770 | #endif |
| 1771 | |
| 1772 | #ifdef PNG_ERROR_TEXT_SUPPORTED |
| 1773 | /* Fatal error in PNG image of libpng - can't continue */ |
| 1774 | PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr, |
| 1775 | png_const_charp error_message), PNG_NORETURN); |
| 1776 | |
| 1777 | /* The same, but the chunk name is prepended to the error string. */ |
| 1778 | PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr, |
| 1779 | png_const_charp error_message), PNG_NORETURN); |
| 1780 | |
| 1781 | #else |
| 1782 | /* Fatal error in PNG image of libpng - can't continue */ |
| 1783 | PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN); |
| 1784 | # define png_error(s1,s2) png_err(s1) |
| 1785 | # define png_chunk_error(s1,s2) png_err(s1) |
| 1786 | #endif |
| 1787 | |
| 1788 | #ifdef PNG_WARNINGS_SUPPORTED |
| 1789 | /* Non-fatal error in libpng. Can continue, but may have a problem. */ |
| 1790 | PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr, |
| 1791 | png_const_charp warning_message)); |
| 1792 | |
| 1793 | /* Non-fatal error in libpng, chunk name is prepended to message. */ |
| 1794 | PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr, |
| 1795 | png_const_charp warning_message)); |
| 1796 | #else |
| 1797 | # define png_warning(s1,s2) ((void)(s1)) |
| 1798 | # define png_chunk_warning(s1,s2) ((void)(s1)) |
| 1799 | #endif |
| 1800 | |
| 1801 | #ifdef PNG_BENIGN_ERRORS_SUPPORTED |
| 1802 | /* Benign error in libpng. Can continue, but may have a problem. |
| 1803 | * User can choose whether to handle as a fatal error or as a warning. */ |
| 1804 | PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr, |
| 1805 | png_const_charp warning_message)); |
| 1806 | |
| 1807 | #ifdef PNG_READ_SUPPORTED |
| 1808 | /* Same, chunk name is prepended to message (only during read) */ |
| 1809 | PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr, |
| 1810 | png_const_charp warning_message)); |
| 1811 | #endif |
| 1812 | |
| 1813 | PNG_EXPORT(109, void, png_set_benign_errors, |
| 1814 | (png_structrp png_ptr, int allowed)); |
| 1815 | #else |
| 1816 | # ifdef PNG_ALLOW_BENIGN_ERRORS |
| 1817 | # define png_benign_error png_warning |
| 1818 | # define png_chunk_benign_error png_chunk_warning |
| 1819 | # else |
| 1820 | # define png_benign_error png_error |
| 1821 | # define png_chunk_benign_error png_chunk_error |
| 1822 | # endif |
| 1823 | #endif |
| 1824 | |
| 1825 | /* The png_set_<chunk> functions are for storing values in the png_info_struct. |
| 1826 | * Similarly, the png_get_<chunk> calls are used to read values from the |
| 1827 | * png_info_struct, either storing the parameters in the passed variables, or |
| 1828 | * setting pointers into the png_info_struct where the data is stored. The |
| 1829 | * png_get_<chunk> functions return a non-zero value if the data was available |
| 1830 | * in info_ptr, or return zero and do not change any of the parameters if the |
| 1831 | * data was not available. |
| 1832 | * |
| 1833 | * These functions should be used instead of directly accessing png_info |
| 1834 | * to avoid problems with future changes in the size and internal layout of |
| 1835 | * png_info_struct. |
| 1836 | */ |
| 1837 | /* Returns "flag" if chunk data is valid in info_ptr. */ |
| 1838 | PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr, |
| 1839 | png_const_inforp info_ptr, png_uint_32 flag)); |
| 1840 | |
| 1841 | /* Returns number of bytes needed to hold a transformed row. */ |
| 1842 | PNG_EXPORT(111, size_t, png_get_rowbytes, (png_const_structrp png_ptr, |
| 1843 | png_const_inforp info_ptr)); |
| 1844 | |
| 1845 | #ifdef PNG_INFO_IMAGE_SUPPORTED |
| 1846 | /* Returns row_pointers, which is an array of pointers to scanlines that was |
| 1847 | * returned from png_read_png(). |
| 1848 | */ |
| 1849 | PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr, |
| 1850 | png_const_inforp info_ptr)); |
| 1851 | |
| 1852 | /* Set row_pointers, which is an array of pointers to scanlines for use |
| 1853 | * by png_write_png(). |
| 1854 | */ |
| 1855 | PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr, |
| 1856 | png_inforp info_ptr, png_bytepp row_pointers)); |
| 1857 | #endif |
| 1858 | |
| 1859 | /* Returns number of color channels in image. */ |
| 1860 | PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr, |
| 1861 | png_const_inforp info_ptr)); |
| 1862 | |
| 1863 | #ifdef PNG_EASY_ACCESS_SUPPORTED |
| 1864 | /* Returns image width in pixels. */ |
| 1865 | PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr, |
| 1866 | png_const_inforp info_ptr)); |
| 1867 | |
| 1868 | /* Returns image height in pixels. */ |
| 1869 | PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr, |
| 1870 | png_const_inforp info_ptr)); |
| 1871 | |
| 1872 | /* Returns image bit_depth. */ |
| 1873 | PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr, |
| 1874 | png_const_inforp info_ptr)); |
| 1875 | |
| 1876 | /* Returns image color_type. */ |
| 1877 | PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr, |
| 1878 | png_const_inforp info_ptr)); |
| 1879 | |
| 1880 | /* Returns image filter_type. */ |
| 1881 | PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr, |
| 1882 | png_const_inforp info_ptr)); |
| 1883 | |
| 1884 | /* Returns image interlace_type. */ |
| 1885 | PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr, |
| 1886 | png_const_inforp info_ptr)); |
| 1887 | |
| 1888 | /* Returns image compression_type. */ |
| 1889 | PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr, |
| 1890 | png_const_inforp info_ptr)); |
| 1891 | |
| 1892 | /* Returns image resolution in pixels per meter, from pHYs chunk data. */ |
| 1893 | PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, |
| 1894 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 1895 | PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, |
| 1896 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 1897 | PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, |
| 1898 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 1899 | |
| 1900 | /* Returns pixel aspect ratio, computed from pHYs chunk data. */ |
| 1901 | PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, |
| 1902 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
| 1903 | PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, |
| 1904 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
| 1905 | |
| 1906 | /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ |
| 1907 | PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, |
| 1908 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 1909 | PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, |
| 1910 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 1911 | PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, |
| 1912 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 1913 | PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, |
| 1914 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 1915 | |
| 1916 | #endif /* EASY_ACCESS */ |
| 1917 | |
| 1918 | #ifdef PNG_READ_SUPPORTED |
| 1919 | /* Returns pointer to signature string read from PNG header */ |
| 1920 | PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr, |
| 1921 | png_const_inforp info_ptr)); |
| 1922 | #endif |
| 1923 | |
| 1924 | #ifdef PNG_bKGD_SUPPORTED |
| 1925 | PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr, |
| 1926 | png_inforp info_ptr, png_color_16p *background)); |
| 1927 | #endif |
| 1928 | |
| 1929 | #ifdef PNG_bKGD_SUPPORTED |
| 1930 | PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr, |
| 1931 | png_inforp info_ptr, png_const_color_16p background)); |
| 1932 | #endif |
| 1933 | |
| 1934 | #ifdef PNG_cHRM_SUPPORTED |
| 1935 | PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr, |
| 1936 | png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x, |
| 1937 | double *red_y, double *green_x, double *green_y, double *blue_x, |
| 1938 | double *blue_y)) |
| 1939 | PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr, |
| 1940 | png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z, |
| 1941 | double *green_X, double *green_Y, double *green_Z, double *blue_X, |
| 1942 | double *blue_Y, double *blue_Z)) |
| 1943 | PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, |
| 1944 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
| 1945 | png_fixed_point *int_white_x, png_fixed_point *int_white_y, |
| 1946 | png_fixed_point *int_red_x, png_fixed_point *int_red_y, |
| 1947 | png_fixed_point *int_green_x, png_fixed_point *int_green_y, |
| 1948 | png_fixed_point *int_blue_x, png_fixed_point *int_blue_y)) |
| 1949 | PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, |
| 1950 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
| 1951 | png_fixed_point *int_red_X, png_fixed_point *int_red_Y, |
| 1952 | png_fixed_point *int_red_Z, png_fixed_point *int_green_X, |
| 1953 | png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, |
| 1954 | png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, |
| 1955 | png_fixed_point *int_blue_Z)) |
| 1956 | #endif |
| 1957 | |
| 1958 | #ifdef PNG_cHRM_SUPPORTED |
| 1959 | PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr, |
| 1960 | png_inforp info_ptr, |
| 1961 | double white_x, double white_y, double red_x, double red_y, double green_x, |
| 1962 | double green_y, double blue_x, double blue_y)) |
| 1963 | PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr, |
| 1964 | png_inforp info_ptr, double red_X, double red_Y, double red_Z, |
| 1965 | double green_X, double green_Y, double green_Z, double blue_X, |
| 1966 | double blue_Y, double blue_Z)) |
| 1967 | PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr, |
| 1968 | png_inforp info_ptr, png_fixed_point int_white_x, |
| 1969 | png_fixed_point int_white_y, png_fixed_point int_red_x, |
| 1970 | png_fixed_point int_red_y, png_fixed_point int_green_x, |
| 1971 | png_fixed_point int_green_y, png_fixed_point int_blue_x, |
| 1972 | png_fixed_point int_blue_y)) |
| 1973 | PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr, |
| 1974 | png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, |
| 1975 | png_fixed_point int_red_Z, png_fixed_point int_green_X, |
| 1976 | png_fixed_point int_green_Y, png_fixed_point int_green_Z, |
| 1977 | png_fixed_point int_blue_X, png_fixed_point int_blue_Y, |
| 1978 | png_fixed_point int_blue_Z)) |
| 1979 | #endif |
| 1980 | |
| 1981 | #ifdef PNG_eXIf_SUPPORTED |
| 1982 | PNG_EXPORT(246, png_uint_32, png_get_eXIf, (png_const_structrp png_ptr, |
| 1983 | png_inforp info_ptr, png_bytep *exif)); |
| 1984 | PNG_EXPORT(247, void, png_set_eXIf, (png_const_structrp png_ptr, |
| 1985 | png_inforp info_ptr, png_bytep exif)); |
| 1986 | |
| 1987 | PNG_EXPORT(248, png_uint_32, png_get_eXIf_1, (png_const_structrp png_ptr, |
| 1988 | png_const_inforp info_ptr, png_uint_32 *num_exif, png_bytep *exif)); |
| 1989 | PNG_EXPORT(249, void, png_set_eXIf_1, (png_const_structrp png_ptr, |
| 1990 | png_inforp info_ptr, png_uint_32 num_exif, png_bytep exif)); |
| 1991 | #endif |
| 1992 | |
| 1993 | #ifdef PNG_gAMA_SUPPORTED |
| 1994 | PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr, |
| 1995 | png_const_inforp info_ptr, double *file_gamma)) |
| 1996 | PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, |
| 1997 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
| 1998 | png_fixed_point *int_file_gamma)) |
| 1999 | #endif |
| 2000 | |
| 2001 | #ifdef PNG_gAMA_SUPPORTED |
| 2002 | PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr, |
| 2003 | png_inforp info_ptr, double file_gamma)) |
| 2004 | PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr, |
| 2005 | png_inforp info_ptr, png_fixed_point int_file_gamma)) |
| 2006 | #endif |
| 2007 | |
| 2008 | #ifdef PNG_hIST_SUPPORTED |
| 2009 | PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr, |
| 2010 | png_inforp info_ptr, png_uint_16p *hist)); |
| 2011 | PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr, |
| 2012 | png_inforp info_ptr, png_const_uint_16p hist)); |
| 2013 | #endif |
| 2014 | |
| 2015 | PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr, |
| 2016 | png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, |
| 2017 | int *bit_depth, int *color_type, int *interlace_method, |
| 2018 | int *compression_method, int *filter_method)); |
| 2019 | |
| 2020 | PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr, |
| 2021 | png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, |
| 2022 | int color_type, int interlace_method, int compression_method, |
| 2023 | int filter_method)); |
| 2024 | |
| 2025 | #ifdef PNG_oFFs_SUPPORTED |
| 2026 | PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr, |
| 2027 | png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, |
| 2028 | int *unit_type)); |
| 2029 | #endif |
| 2030 | |
| 2031 | #ifdef PNG_oFFs_SUPPORTED |
| 2032 | PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr, |
| 2033 | png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y, |
| 2034 | int unit_type)); |
| 2035 | #endif |
| 2036 | |
| 2037 | #ifdef PNG_pCAL_SUPPORTED |
| 2038 | PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr, |
| 2039 | png_inforp info_ptr, png_charp *purpose, png_int_32 *X0, |
| 2040 | png_int_32 *X1, int *type, int *nparams, png_charp *units, |
| 2041 | png_charpp *params)); |
| 2042 | #endif |
| 2043 | |
| 2044 | #ifdef PNG_pCAL_SUPPORTED |
| 2045 | PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr, |
| 2046 | png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1, |
| 2047 | int type, int nparams, png_const_charp units, png_charpp params)); |
| 2048 | #endif |
| 2049 | |
| 2050 | #ifdef PNG_pHYs_SUPPORTED |
| 2051 | PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr, |
| 2052 | png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
| 2053 | int *unit_type)); |
| 2054 | #endif |
| 2055 | |
| 2056 | #ifdef PNG_pHYs_SUPPORTED |
| 2057 | PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr, |
| 2058 | png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); |
| 2059 | #endif |
| 2060 | |
| 2061 | PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr, |
| 2062 | png_inforp info_ptr, png_colorp *palette, int *num_palette)); |
| 2063 | |
| 2064 | PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr, |
| 2065 | png_inforp info_ptr, png_const_colorp palette, int num_palette)); |
| 2066 | |
| 2067 | #ifdef PNG_sBIT_SUPPORTED |
| 2068 | PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr, |
| 2069 | png_inforp info_ptr, png_color_8p *sig_bit)); |
| 2070 | #endif |
| 2071 | |
| 2072 | #ifdef PNG_sBIT_SUPPORTED |
| 2073 | PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr, |
| 2074 | png_inforp info_ptr, png_const_color_8p sig_bit)); |
| 2075 | #endif |
| 2076 | |
| 2077 | #ifdef PNG_sRGB_SUPPORTED |
| 2078 | PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr, |
| 2079 | png_const_inforp info_ptr, int *file_srgb_intent)); |
| 2080 | #endif |
| 2081 | |
| 2082 | #ifdef PNG_sRGB_SUPPORTED |
| 2083 | PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr, |
| 2084 | png_inforp info_ptr, int srgb_intent)); |
| 2085 | PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr, |
| 2086 | png_inforp info_ptr, int srgb_intent)); |
| 2087 | #endif |
| 2088 | |
| 2089 | #ifdef PNG_iCCP_SUPPORTED |
| 2090 | PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr, |
| 2091 | png_inforp info_ptr, png_charpp name, int *compression_type, |
| 2092 | png_bytepp profile, png_uint_32 *proflen)); |
| 2093 | #endif |
| 2094 | |
| 2095 | #ifdef PNG_iCCP_SUPPORTED |
| 2096 | PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr, |
| 2097 | png_inforp info_ptr, png_const_charp name, int compression_type, |
| 2098 | png_const_bytep profile, png_uint_32 proflen)); |
| 2099 | #endif |
| 2100 | |
| 2101 | #ifdef PNG_sPLT_SUPPORTED |
| 2102 | PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr, |
| 2103 | png_inforp info_ptr, png_sPLT_tpp entries)); |
| 2104 | #endif |
| 2105 | |
| 2106 | #ifdef PNG_sPLT_SUPPORTED |
| 2107 | PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr, |
| 2108 | png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)); |
| 2109 | #endif |
| 2110 | |
| 2111 | #ifdef PNG_TEXT_SUPPORTED |
| 2112 | /* png_get_text also returns the number of text chunks in *num_text */ |
| 2113 | PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr, |
| 2114 | png_inforp info_ptr, png_textp *text_ptr, int *num_text)); |
| 2115 | #endif |
| 2116 | |
| 2117 | /* Note while png_set_text() will accept a structure whose text, |
| 2118 | * language, and translated keywords are NULL pointers, the structure |
| 2119 | * returned by png_get_text will always contain regular |
| 2120 | * zero-terminated C strings. They might be empty strings but |
| 2121 | * they will never be NULL pointers. |
| 2122 | */ |
| 2123 | |
| 2124 | #ifdef PNG_TEXT_SUPPORTED |
| 2125 | PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr, |
| 2126 | png_inforp info_ptr, png_const_textp text_ptr, int num_text)); |
| 2127 | #endif |
| 2128 | |
| 2129 | #ifdef PNG_tIME_SUPPORTED |
| 2130 | PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr, |
| 2131 | png_inforp info_ptr, png_timep *mod_time)); |
| 2132 | #endif |
| 2133 | |
| 2134 | #ifdef PNG_tIME_SUPPORTED |
| 2135 | PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr, |
| 2136 | png_inforp info_ptr, png_const_timep mod_time)); |
| 2137 | #endif |
| 2138 | |
| 2139 | #ifdef PNG_tRNS_SUPPORTED |
| 2140 | PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr, |
| 2141 | png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans, |
| 2142 | png_color_16p *trans_color)); |
| 2143 | #endif |
| 2144 | |
| 2145 | #ifdef PNG_tRNS_SUPPORTED |
| 2146 | PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr, |
| 2147 | png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans, |
| 2148 | png_const_color_16p trans_color)); |
| 2149 | #endif |
| 2150 | |
| 2151 | #ifdef PNG_sCAL_SUPPORTED |
| 2152 | PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr, |
| 2153 | png_const_inforp info_ptr, int *unit, double *width, double *height)) |
| 2154 | #if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \ |
| 2155 | defined(PNG_FLOATING_POINT_SUPPORTED) |
| 2156 | /* NOTE: this API is currently implemented using floating point arithmetic, |
| 2157 | * consequently it can only be used on systems with floating point support. |
| 2158 | * In any case the range of values supported by png_fixed_point is small and it |
| 2159 | * is highly recommended that png_get_sCAL_s be used instead. |
| 2160 | */ |
| 2161 | PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, |
| 2162 | (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, |
| 2163 | png_fixed_point *width, png_fixed_point *height)) |
| 2164 | #endif |
| 2165 | PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, |
| 2166 | (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, |
| 2167 | png_charpp swidth, png_charpp sheight)); |
| 2168 | |
| 2169 | PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr, |
| 2170 | png_inforp info_ptr, int unit, double width, double height)) |
| 2171 | PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr, |
| 2172 | png_inforp info_ptr, int unit, png_fixed_point width, |
| 2173 | png_fixed_point height)) |
| 2174 | PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr, |
| 2175 | png_inforp info_ptr, int unit, |
| 2176 | png_const_charp swidth, png_const_charp sheight)); |
| 2177 | #endif /* sCAL */ |
| 2178 | |
| 2179 | #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED |
| 2180 | /* Provide the default handling for all unknown chunks or, optionally, for |
| 2181 | * specific unknown chunks. |
| 2182 | * |
| 2183 | * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was |
| 2184 | * ignored and the default was used, the per-chunk setting only had an effect on |
| 2185 | * write. If you wish to have chunk-specific handling on read in code that must |
| 2186 | * work on earlier versions you must use a user chunk callback to specify the |
| 2187 | * desired handling (keep or discard.) |
| 2188 | * |
| 2189 | * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The |
| 2190 | * parameter is interpreted as follows: |
| 2191 | * |
| 2192 | * READ: |
| 2193 | * PNG_HANDLE_CHUNK_AS_DEFAULT: |
| 2194 | * Known chunks: do normal libpng processing, do not keep the chunk (but |
| 2195 | * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED) |
| 2196 | * Unknown chunks: for a specific chunk use the global default, when used |
| 2197 | * as the default discard the chunk data. |
| 2198 | * PNG_HANDLE_CHUNK_NEVER: |
| 2199 | * Discard the chunk data. |
| 2200 | * PNG_HANDLE_CHUNK_IF_SAFE: |
| 2201 | * Keep the chunk data if the chunk is not critical else raise a chunk |
| 2202 | * error. |
| 2203 | * PNG_HANDLE_CHUNK_ALWAYS: |
| 2204 | * Keep the chunk data. |
| 2205 | * |
| 2206 | * If the chunk data is saved it can be retrieved using png_get_unknown_chunks, |
| 2207 | * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent |
| 2208 | * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks |
| 2209 | * it simply resets the behavior to the libpng default. |
| 2210 | * |
| 2211 | * INTERACTION WITH USER CHUNK CALLBACKS: |
| 2212 | * The per-chunk handling is always used when there is a png_user_chunk_ptr |
| 2213 | * callback and the callback returns 0; the chunk is then always stored *unless* |
| 2214 | * it is critical and the per-chunk setting is other than ALWAYS. Notice that |
| 2215 | * the global default is *not* used in this case. (In effect the per-chunk |
| 2216 | * value is incremented to at least IF_SAFE.) |
| 2217 | * |
| 2218 | * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and |
| 2219 | * per-chunk defaults will be honored. If you want to preserve the current |
| 2220 | * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE |
| 2221 | * as the default - if you don't do this libpng 1.6 will issue a warning. |
| 2222 | * |
| 2223 | * If you want unhandled unknown chunks to be discarded in libpng 1.6 and |
| 2224 | * earlier simply return '1' (handled). |
| 2225 | * |
| 2226 | * PNG_HANDLE_AS_UNKNOWN_SUPPORTED: |
| 2227 | * If this is *not* set known chunks will always be handled by libpng and |
| 2228 | * will never be stored in the unknown chunk list. Known chunks listed to |
| 2229 | * png_set_keep_unknown_chunks will have no effect. If it is set then known |
| 2230 | * chunks listed with a keep other than AS_DEFAULT will *never* be processed |
| 2231 | * by libpng, in addition critical chunks must either be processed by the |
| 2232 | * callback or saved. |
| 2233 | * |
| 2234 | * The IHDR and IEND chunks must not be listed. Because this turns off the |
| 2235 | * default handling for chunks that would otherwise be recognized the |
| 2236 | * behavior of libpng transformations may well become incorrect! |
| 2237 | * |
| 2238 | * WRITE: |
| 2239 | * When writing chunks the options only apply to the chunks specified by |
| 2240 | * png_set_unknown_chunks (below), libpng will *always* write known chunks |
| 2241 | * required by png_set_ calls and will always write the core critical chunks |
| 2242 | * (as required for PLTE). |
| 2243 | * |
| 2244 | * Each chunk in the png_set_unknown_chunks list is looked up in the |
| 2245 | * png_set_keep_unknown_chunks list to find the keep setting, this is then |
| 2246 | * interpreted as follows: |
| 2247 | * |
| 2248 | * PNG_HANDLE_CHUNK_AS_DEFAULT: |
| 2249 | * Write safe-to-copy chunks and write other chunks if the global |
| 2250 | * default is set to _ALWAYS, otherwise don't write this chunk. |
| 2251 | * PNG_HANDLE_CHUNK_NEVER: |
| 2252 | * Do not write the chunk. |
| 2253 | * PNG_HANDLE_CHUNK_IF_SAFE: |
| 2254 | * Write the chunk if it is safe-to-copy, otherwise do not write it. |
| 2255 | * PNG_HANDLE_CHUNK_ALWAYS: |
| 2256 | * Write the chunk. |
| 2257 | * |
| 2258 | * Note that the default behavior is effectively the opposite of the read case - |
| 2259 | * in read unknown chunks are not stored by default, in write they are written |
| 2260 | * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different |
| 2261 | * - on write the safe-to-copy bit is checked, on read the critical bit is |
| 2262 | * checked and on read if the chunk is critical an error will be raised. |
| 2263 | * |
| 2264 | * num_chunks: |
| 2265 | * =========== |
| 2266 | * If num_chunks is positive, then the "keep" parameter specifies the manner |
| 2267 | * for handling only those chunks appearing in the chunk_list array, |
| 2268 | * otherwise the chunk list array is ignored. |
| 2269 | * |
| 2270 | * If num_chunks is 0 the "keep" parameter specifies the default behavior for |
| 2271 | * unknown chunks, as described above. |
| 2272 | * |
| 2273 | * If num_chunks is negative, then the "keep" parameter specifies the manner |
| 2274 | * for handling all unknown chunks plus all chunks recognized by libpng |
| 2275 | * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to |
| 2276 | * be processed by libpng. |
| 2277 | */ |
| 2278 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
| 2279 | PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr, |
| 2280 | int keep, png_const_bytep chunk_list, int num_chunks)); |
| 2281 | #endif /* HANDLE_AS_UNKNOWN */ |
| 2282 | |
| 2283 | /* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned; |
| 2284 | * the result is therefore true (non-zero) if special handling is required, |
| 2285 | * false for the default handling. |
| 2286 | */ |
| 2287 | PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr, |
| 2288 | png_const_bytep chunk_name)); |
| 2289 | #endif /* SET_UNKNOWN_CHUNKS */ |
| 2290 | |
| 2291 | #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED |
| 2292 | PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr, |
| 2293 | png_inforp info_ptr, png_const_unknown_chunkp unknowns, |
| 2294 | int num_unknowns)); |
| 2295 | /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added |
| 2296 | * unknowns to the location currently stored in the png_struct. This is |
| 2297 | * invariably the wrong value on write. To fix this call the following API |
| 2298 | * for each chunk in the list with the correct location. If you know your |
| 2299 | * code won't be compiled on earlier versions you can rely on |
| 2300 | * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing |
| 2301 | * the correct thing. |
| 2302 | */ |
| 2303 | |
| 2304 | PNG_EXPORT(175, void, png_set_unknown_chunk_location, |
| 2305 | (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location)); |
| 2306 | |
| 2307 | PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr, |
| 2308 | png_inforp info_ptr, png_unknown_chunkpp entries)); |
| 2309 | #endif |
| 2310 | |
| 2311 | /* Png_free_data() will turn off the "valid" flag for anything it frees. |
| 2312 | * If you need to turn it off for a chunk that your application has freed, |
| 2313 | * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); |
| 2314 | */ |
| 2315 | PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr, |
| 2316 | png_inforp info_ptr, int mask)); |
| 2317 | |
| 2318 | #ifdef PNG_INFO_IMAGE_SUPPORTED |
| 2319 | /* The "params" pointer is currently not used and is for future expansion. */ |
| 2320 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED |
| 2321 | PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr, |
| 2322 | int transforms, png_voidp params)); |
| 2323 | #endif |
| 2324 | #ifdef PNG_WRITE_SUPPORTED |
| 2325 | PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr, |
| 2326 | int transforms, png_voidp params)); |
| 2327 | #endif |
| 2328 | #endif |
| 2329 | |
| 2330 | PNG_EXPORT(180, png_const_charp, png_get_copyright, |
| 2331 | (png_const_structrp png_ptr)); |
| 2332 | PNG_EXPORT(181, png_const_charp, png_get_header_ver, |
| 2333 | (png_const_structrp png_ptr)); |
| 2334 | PNG_EXPORT(182, png_const_charp, png_get_header_version, |
| 2335 | (png_const_structrp png_ptr)); |
| 2336 | PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, |
| 2337 | (png_const_structrp png_ptr)); |
| 2338 | |
| 2339 | #ifdef PNG_MNG_FEATURES_SUPPORTED |
| 2340 | PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr, |
| 2341 | png_uint_32 mng_features_permitted)); |
| 2342 | #endif |
| 2343 | |
| 2344 | /* For use in png_set_keep_unknown, added to version 1.2.6 */ |
| 2345 | #define PNG_HANDLE_CHUNK_AS_DEFAULT 0 |
| 2346 | #define PNG_HANDLE_CHUNK_NEVER 1 |
| 2347 | #define PNG_HANDLE_CHUNK_IF_SAFE 2 |
| 2348 | #define PNG_HANDLE_CHUNK_ALWAYS 3 |
| 2349 | #define PNG_HANDLE_CHUNK_LAST 4 |
| 2350 | |
| 2351 | /* Strip the prepended error numbers ("#nnn ") from error and warning |
| 2352 | * messages before passing them to the error or warning handler. |
| 2353 | */ |
| 2354 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
| 2355 | PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr, |
| 2356 | png_uint_32 strip_mode)); |
| 2357 | #endif |
| 2358 | |
| 2359 | /* Added in libpng-1.2.6 */ |
| 2360 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
| 2361 | PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr, |
| 2362 | png_uint_32 user_width_max, png_uint_32 user_height_max)); |
| 2363 | PNG_EXPORT(187, png_uint_32, png_get_user_width_max, |
| 2364 | (png_const_structrp png_ptr)); |
| 2365 | PNG_EXPORT(188, png_uint_32, png_get_user_height_max, |
| 2366 | (png_const_structrp png_ptr)); |
| 2367 | /* Added in libpng-1.4.0 */ |
| 2368 | PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr, |
| 2369 | png_uint_32 user_chunk_cache_max)); |
| 2370 | PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, |
| 2371 | (png_const_structrp png_ptr)); |
| 2372 | /* Added in libpng-1.4.1 */ |
| 2373 | PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr, |
| 2374 | png_alloc_size_t user_chunk_cache_max)); |
| 2375 | PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, |
| 2376 | (png_const_structrp png_ptr)); |
| 2377 | #endif |
| 2378 | |
| 2379 | #if defined(PNG_INCH_CONVERSIONS_SUPPORTED) |
| 2380 | PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, |
| 2381 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 2382 | |
| 2383 | PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, |
| 2384 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 2385 | |
| 2386 | PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, |
| 2387 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
| 2388 | |
| 2389 | PNG_FP_EXPORT(196, float, png_get_x_offset_inches, |
| 2390 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
| 2391 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
| 2392 | PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, |
| 2393 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
| 2394 | #endif |
| 2395 | |
| 2396 | PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr, |
| 2397 | png_const_inforp info_ptr)) |
| 2398 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
| 2399 | PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, |
| 2400 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
| 2401 | #endif |
| 2402 | |
| 2403 | # ifdef PNG_pHYs_SUPPORTED |
| 2404 | PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr, |
| 2405 | png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
| 2406 | int *unit_type)); |
| 2407 | # endif /* pHYs */ |
| 2408 | #endif /* INCH_CONVERSIONS */ |
| 2409 | |
| 2410 | /* Added in libpng-1.4.0 */ |
| 2411 | #ifdef PNG_IO_STATE_SUPPORTED |
| 2412 | PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr)); |
| 2413 | |
| 2414 | /* Removed from libpng 1.6; use png_get_io_chunk_type. */ |
| 2415 | PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr), |
| 2416 | PNG_DEPRECATED) |
| 2417 | |
| 2418 | PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, |
| 2419 | (png_const_structrp png_ptr)); |
| 2420 | |
| 2421 | /* The flags returned by png_get_io_state() are the following: */ |
| 2422 | # define PNG_IO_NONE 0x0000 /* no I/O at this moment */ |
| 2423 | # define PNG_IO_READING 0x0001 /* currently reading */ |
| 2424 | # define PNG_IO_WRITING 0x0002 /* currently writing */ |
| 2425 | # define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ |
| 2426 | # define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ |
| 2427 | # define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ |
| 2428 | # define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ |
| 2429 | # define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ |
| 2430 | # define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ |
| 2431 | #endif /* IO_STATE */ |
| 2432 | |
| 2433 | /* Interlace support. The following macros are always defined so that if |
| 2434 | * libpng interlace handling is turned off the macros may be used to handle |
| 2435 | * interlaced images within the application. |
| 2436 | */ |
| 2437 | #define PNG_INTERLACE_ADAM7_PASSES 7 |
| 2438 | |
| 2439 | /* Two macros to return the first row and first column of the original, |
| 2440 | * full, image which appears in a given pass. 'pass' is in the range 0 |
| 2441 | * to 6 and the result is in the range 0 to 7. |
| 2442 | */ |
| 2443 | #define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) |
| 2444 | #define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) |
| 2445 | |
| 2446 | /* A macro to return the offset between pixels in the output row for a pair of |
| 2447 | * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that |
| 2448 | * follows. Note that ROW_OFFSET is the offset from one row to the next whereas |
| 2449 | * COL_OFFSET is from one column to the next, within a row. |
| 2450 | */ |
| 2451 | #define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) |
| 2452 | #define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) |
| 2453 | |
| 2454 | /* Two macros to help evaluate the number of rows or columns in each |
| 2455 | * pass. This is expressed as a shift - effectively log2 of the number or |
| 2456 | * rows or columns in each 8x8 tile of the original image. |
| 2457 | */ |
| 2458 | #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) |
| 2459 | #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) |
| 2460 | |
| 2461 | /* Hence two macros to determine the number of rows or columns in a given |
| 2462 | * pass of an image given its height or width. In fact these macros may |
| 2463 | * return non-zero even though the sub-image is empty, because the other |
| 2464 | * dimension may be empty for a small image. |
| 2465 | */ |
| 2466 | #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ |
| 2467 | -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) |
| 2468 | #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ |
| 2469 | -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) |
| 2470 | |
| 2471 | /* For the reader row callbacks (both progressive and sequential) it is |
| 2472 | * necessary to find the row in the output image given a row in an interlaced |
| 2473 | * image, so two more macros: |
| 2474 | */ |
| 2475 | #define PNG_ROW_FROM_PASS_ROW(y_in, pass) \ |
| 2476 | (((y_in)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) |
| 2477 | #define PNG_COL_FROM_PASS_COL(x_in, pass) \ |
| 2478 | (((x_in)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) |
| 2479 | |
| 2480 | /* Two macros which return a boolean (0 or 1) saying whether the given row |
| 2481 | * or column is in a particular pass. These use a common utility macro that |
| 2482 | * returns a mask for a given pass - the offset 'off' selects the row or |
| 2483 | * column version. The mask has the appropriate bit set for each column in |
| 2484 | * the tile. |
| 2485 | */ |
| 2486 | #define PNG_PASS_MASK(pass,off) ( \ |
| 2487 | ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \ |
| 2488 | ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) |
| 2489 | |
| 2490 | #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ |
| 2491 | ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) |
| 2492 | #define PNG_COL_IN_INTERLACE_PASS(x, pass) \ |
| 2493 | ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) |
| 2494 | |
| 2495 | #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED |
| 2496 | /* With these routines we avoid an integer divide, which will be slower on |
| 2497 | * most machines. However, it does take more operations than the corresponding |
| 2498 | * divide method, so it may be slower on a few RISC systems. There are two |
| 2499 | * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. |
| 2500 | * |
| 2501 | * Note that the rounding factors are NOT supposed to be the same! 128 and |
| 2502 | * 32768 are correct for the NODIV code; 127 and 32767 are correct for the |
| 2503 | * standard method. |
| 2504 | * |
| 2505 | * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] |
| 2506 | */ |
| 2507 | |
| 2508 | /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ |
| 2509 | |
| 2510 | # define png_composite(composite, fg, alpha, bg) \ |
| 2511 | { \ |
| 2512 | png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ |
| 2513 | * (png_uint_16)(alpha) \ |
| 2514 | + (png_uint_16)(bg)*(png_uint_16)(255 \ |
| 2515 | - (png_uint_16)(alpha)) + 128); \ |
| 2516 | (composite) = (png_byte)(((temp + (temp >> 8)) >> 8) & 0xff); \ |
| 2517 | } |
| 2518 | |
| 2519 | # define png_composite_16(composite, fg, alpha, bg) \ |
| 2520 | { \ |
| 2521 | png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ |
| 2522 | * (png_uint_32)(alpha) \ |
| 2523 | + (png_uint_32)(bg)*(65535 \ |
| 2524 | - (png_uint_32)(alpha)) + 32768); \ |
| 2525 | (composite) = (png_uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); \ |
| 2526 | } |
| 2527 | |
| 2528 | #else /* Standard method using integer division */ |
| 2529 | |
| 2530 | # define png_composite(composite, fg, alpha, bg) \ |
| 2531 | (composite) = \ |
| 2532 | (png_byte)(0xff & (((png_uint_16)(fg) * (png_uint_16)(alpha) + \ |
| 2533 | (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ |
| 2534 | 127) / 255)) |
| 2535 | |
| 2536 | # define png_composite_16(composite, fg, alpha, bg) \ |
| 2537 | (composite) = \ |
| 2538 | (png_uint_16)(0xffff & (((png_uint_32)(fg) * (png_uint_32)(alpha) + \ |
| 2539 | (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ |
| 2540 | 32767) / 65535)) |
| 2541 | #endif /* READ_COMPOSITE_NODIV */ |
| 2542 | |
| 2543 | #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED |
| 2544 | PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); |
| 2545 | PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); |
| 2546 | PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); |
| 2547 | #endif |
| 2548 | |
| 2549 | PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr, |
| 2550 | png_const_bytep buf)); |
| 2551 | /* No png_get_int_16 -- may be added if there's a real need for it. */ |
| 2552 | |
| 2553 | /* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ |
| 2554 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
| 2555 | PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); |
| 2556 | #endif |
| 2557 | #ifdef PNG_SAVE_INT_32_SUPPORTED |
| 2558 | PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); |
| 2559 | #endif |
| 2560 | |
| 2561 | /* Place a 16-bit number into a buffer in PNG byte order. |
| 2562 | * The parameter is declared unsigned int, not png_uint_16, |
| 2563 | * just to avoid potential problems on pre-ANSI C compilers. |
| 2564 | */ |
| 2565 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
| 2566 | PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); |
| 2567 | /* No png_save_int_16 -- may be added if there's a real need for it. */ |
| 2568 | #endif |
| 2569 | |
| 2570 | #ifdef PNG_USE_READ_MACROS |
| 2571 | /* Inline macros to do direct reads of bytes from the input buffer. |
| 2572 | * The png_get_int_32() routine assumes we are using two's complement |
| 2573 | * format for negative values, which is almost certainly true. |
| 2574 | */ |
| 2575 | # define PNG_get_uint_32(buf) \ |
| 2576 | (((png_uint_32)(*(buf)) << 24) + \ |
| 2577 | ((png_uint_32)(*((buf) + 1)) << 16) + \ |
| 2578 | ((png_uint_32)(*((buf) + 2)) << 8) + \ |
| 2579 | ((png_uint_32)(*((buf) + 3)))) |
| 2580 | |
| 2581 | /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the |
| 2582 | * function) incorrectly returned a value of type png_uint_32. |
| 2583 | */ |
| 2584 | # define PNG_get_uint_16(buf) \ |
| 2585 | ((png_uint_16) \ |
| 2586 | (((unsigned int)(*(buf)) << 8) + \ |
| 2587 | ((unsigned int)(*((buf) + 1))))) |
| 2588 | |
| 2589 | # define PNG_get_int_32(buf) \ |
| 2590 | ((png_int_32)((*(buf) & 0x80) \ |
| 2591 | ? -((png_int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \ |
| 2592 | : (png_int_32)png_get_uint_32(buf))) |
| 2593 | |
| 2594 | /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h, |
| 2595 | * but defining a macro name prefixed with PNG_PREFIX. |
| 2596 | */ |
| 2597 | # ifndef PNG_PREFIX |
| 2598 | # define png_get_uint_32(buf) PNG_get_uint_32(buf) |
| 2599 | # define png_get_uint_16(buf) PNG_get_uint_16(buf) |
| 2600 | # define png_get_int_32(buf) PNG_get_int_32(buf) |
| 2601 | # endif |
| 2602 | #else |
| 2603 | # ifdef PNG_PREFIX |
| 2604 | /* No macros; revert to the (redefined) function */ |
| 2605 | # define PNG_get_uint_32 (png_get_uint_32) |
| 2606 | # define PNG_get_uint_16 (png_get_uint_16) |
| 2607 | # define PNG_get_int_32 (png_get_int_32) |
| 2608 | # endif |
| 2609 | #endif |
| 2610 | |
| 2611 | #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED |
| 2612 | PNG_EXPORT(242, void, png_set_check_for_invalid_index, |
| 2613 | (png_structrp png_ptr, int allowed)); |
| 2614 | # ifdef PNG_GET_PALETTE_MAX_SUPPORTED |
| 2615 | PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr, |
| 2616 | png_const_infop info_ptr)); |
| 2617 | # endif |
| 2618 | #endif /* CHECK_FOR_INVALID_INDEX */ |
| 2619 | |
| 2620 | /******************************************************************************* |
| 2621 | * Section 5: SIMPLIFIED API |
| 2622 | ******************************************************************************* |
| 2623 | * |
| 2624 | * Please read the documentation in libpng-manual.txt (TODO: write said |
| 2625 | * documentation) if you don't understand what follows. |
| 2626 | * |
| 2627 | * The simplified API hides the details of both libpng and the PNG file format |
| 2628 | * itself. It allows PNG files to be read into a very limited number of |
| 2629 | * in-memory bitmap formats or to be written from the same formats. If these |
| 2630 | * formats do not accommodate your needs then you can, and should, use the more |
| 2631 | * sophisticated APIs above - these support a wide variety of in-memory formats |
| 2632 | * and a wide variety of sophisticated transformations to those formats as well |
| 2633 | * as a wide variety of APIs to manipulate ancillary information. |
| 2634 | * |
| 2635 | * To read a PNG file using the simplified API: |
| 2636 | * |
| 2637 | * 1) Declare a 'png_image' structure (see below) on the stack, set the |
| 2638 | * version field to PNG_IMAGE_VERSION and the 'opaque' pointer to NULL |
| 2639 | * (this is REQUIRED, your program may crash if you don't do it.) |
| 2640 | * 2) Call the appropriate png_image_begin_read... function. |
| 2641 | * 3) Set the png_image 'format' member to the required sample format. |
| 2642 | * 4) Allocate a buffer for the image and, if required, the color-map. |
| 2643 | * 5) Call png_image_finish_read to read the image and, if required, the |
| 2644 | * color-map into your buffers. |
| 2645 | * |
| 2646 | * There are no restrictions on the format of the PNG input itself; all valid |
| 2647 | * color types, bit depths, and interlace methods are acceptable, and the |
| 2648 | * input image is transformed as necessary to the requested in-memory format |
| 2649 | * during the png_image_finish_read() step. The only caveat is that if you |
| 2650 | * request a color-mapped image from a PNG that is full-color or makes |
| 2651 | * complex use of an alpha channel the transformation is extremely lossy and the |
| 2652 | * result may look terrible. |
| 2653 | * |
| 2654 | * To write a PNG file using the simplified API: |
| 2655 | * |
| 2656 | * 1) Declare a 'png_image' structure on the stack and memset() it to all zero. |
| 2657 | * 2) Initialize the members of the structure that describe the image, setting |
| 2658 | * the 'format' member to the format of the image samples. |
| 2659 | * 3) Call the appropriate png_image_write... function with a pointer to the |
| 2660 | * image and, if necessary, the color-map to write the PNG data. |
| 2661 | * |
| 2662 | * png_image is a structure that describes the in-memory format of an image |
| 2663 | * when it is being read or defines the in-memory format of an image that you |
| 2664 | * need to write: |
| 2665 | */ |
| 2666 | #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) || \ |
| 2667 | defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) |
| 2668 | |
| 2669 | #define PNG_IMAGE_VERSION 1 |
| 2670 | |
| 2671 | typedef struct png_control *png_controlp; |
| 2672 | typedef struct |
| 2673 | { |
| 2674 | png_controlp opaque; /* Initialize to NULL, free with png_image_free */ |
| 2675 | png_uint_32 version; /* Set to PNG_IMAGE_VERSION */ |
| 2676 | png_uint_32 width; /* Image width in pixels (columns) */ |
| 2677 | png_uint_32 height; /* Image height in pixels (rows) */ |
| 2678 | png_uint_32 format; /* Image format as defined below */ |
| 2679 | png_uint_32 flags; /* A bit mask containing informational flags */ |
| 2680 | png_uint_32 colormap_entries; |
| 2681 | /* Number of entries in the color-map */ |
| 2682 | |
| 2683 | /* In the event of an error or warning the following field will be set to a |
| 2684 | * non-zero value and the 'message' field will contain a '\0' terminated |
| 2685 | * string with the libpng error or warning message. If both warnings and |
| 2686 | * an error were encountered, only the error is recorded. If there |
| 2687 | * are multiple warnings, only the first one is recorded. |
| 2688 | * |
| 2689 | * The upper 30 bits of this value are reserved, the low two bits contain |
| 2690 | * a value as follows: |
| 2691 | */ |
| 2692 | # define PNG_IMAGE_WARNING 1 |
| 2693 | # define PNG_IMAGE_ERROR 2 |
| 2694 | /* |
| 2695 | * The result is a two-bit code such that a value more than 1 indicates |
| 2696 | * a failure in the API just called: |
| 2697 | * |
| 2698 | * 0 - no warning or error |
| 2699 | * 1 - warning |
| 2700 | * 2 - error |
| 2701 | * 3 - error preceded by warning |
| 2702 | */ |
| 2703 | # define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1) |
| 2704 | |
| 2705 | png_uint_32 warning_or_error; |
| 2706 | |
| 2707 | char message[64]; |
| 2708 | } png_image, *png_imagep; |
| 2709 | |
| 2710 | /* The samples of the image have one to four channels whose components have |
| 2711 | * original values in the range 0 to 1.0: |
| 2712 | * |
| 2713 | * 1: A single gray or luminance channel (G). |
| 2714 | * 2: A gray/luminance channel and an alpha channel (GA). |
| 2715 | * 3: Three red, green, blue color channels (RGB). |
| 2716 | * 4: Three color channels and an alpha channel (RGBA). |
| 2717 | * |
| 2718 | * The components are encoded in one of two ways: |
| 2719 | * |
| 2720 | * a) As a small integer, value 0..255, contained in a single byte. For the |
| 2721 | * alpha channel the original value is simply value/255. For the color or |
| 2722 | * luminance channels the value is encoded according to the sRGB specification |
| 2723 | * and matches the 8-bit format expected by typical display devices. |
| 2724 | * |
| 2725 | * The color/gray channels are not scaled (pre-multiplied) by the alpha |
| 2726 | * channel and are suitable for passing to color management software. |
| 2727 | * |
| 2728 | * b) As a value in the range 0..65535, contained in a 2-byte integer. All |
| 2729 | * channels can be converted to the original value by dividing by 65535; all |
| 2730 | * channels are linear. Color channels use the RGB encoding (RGB end-points) of |
| 2731 | * the sRGB specification. This encoding is identified by the |
| 2732 | * PNG_FORMAT_FLAG_LINEAR flag below. |
| 2733 | * |
| 2734 | * When the simplified API needs to convert between sRGB and linear colorspaces, |
| 2735 | * the actual sRGB transfer curve defined in the sRGB specification (see the |
| 2736 | * article at <https://en.wikipedia.org/wiki/SRGB>) is used, not the gamma=1/2.2 |
| 2737 | * approximation used elsewhere in libpng. |
| 2738 | * |
| 2739 | * When an alpha channel is present it is expected to denote pixel coverage |
| 2740 | * of the color or luminance channels and is returned as an associated alpha |
| 2741 | * channel: the color/gray channels are scaled (pre-multiplied) by the alpha |
| 2742 | * value. |
| 2743 | * |
| 2744 | * The samples are either contained directly in the image data, between 1 and 8 |
| 2745 | * bytes per pixel according to the encoding, or are held in a color-map indexed |
| 2746 | * by bytes in the image data. In the case of a color-map the color-map entries |
| 2747 | * are individual samples, encoded as above, and the image data has one byte per |
| 2748 | * pixel to select the relevant sample from the color-map. |
| 2749 | */ |
| 2750 | |
| 2751 | /* PNG_FORMAT_* |
| 2752 | * |
| 2753 | * #defines to be used in png_image::format. Each #define identifies a |
| 2754 | * particular layout of sample data and, if present, alpha values. There are |
| 2755 | * separate defines for each of the two component encodings. |
| 2756 | * |
| 2757 | * A format is built up using single bit flag values. All combinations are |
| 2758 | * valid. Formats can be built up from the flag values or you can use one of |
| 2759 | * the predefined values below. When testing formats always use the FORMAT_FLAG |
| 2760 | * macros to test for individual features - future versions of the library may |
| 2761 | * add new flags. |
| 2762 | * |
| 2763 | * When reading or writing color-mapped images the format should be set to the |
| 2764 | * format of the entries in the color-map then png_image_{read,write}_colormap |
| 2765 | * called to read or write the color-map and set the format correctly for the |
| 2766 | * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly! |
| 2767 | * |
| 2768 | * NOTE: libpng can be built with particular features disabled. If you see |
| 2769 | * compiler errors because the definition of one of the following flags has been |
| 2770 | * compiled out it is because libpng does not have the required support. It is |
| 2771 | * possible, however, for the libpng configuration to enable the format on just |
| 2772 | * read or just write; in that case you may see an error at run time. You can |
| 2773 | * guard against this by checking for the definition of the appropriate |
| 2774 | * "_SUPPORTED" macro, one of: |
| 2775 | * |
| 2776 | * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED |
| 2777 | */ |
| 2778 | #define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */ |
| 2779 | #define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */ |
| 2780 | #define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2-byte channels else 1-byte */ |
| 2781 | #define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */ |
| 2782 | |
| 2783 | #ifdef PNG_FORMAT_BGR_SUPPORTED |
| 2784 | # define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */ |
| 2785 | #endif |
| 2786 | |
| 2787 | #ifdef PNG_FORMAT_AFIRST_SUPPORTED |
| 2788 | # define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */ |
| 2789 | #endif |
| 2790 | |
| 2791 | #define PNG_FORMAT_FLAG_ASSOCIATED_ALPHA 0x40U /* alpha channel is associated */ |
| 2792 | |
| 2793 | /* Commonly used formats have predefined macros. |
| 2794 | * |
| 2795 | * First the single byte (sRGB) formats: |
| 2796 | */ |
| 2797 | #define PNG_FORMAT_GRAY 0 |
| 2798 | #define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA |
| 2799 | #define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST) |
| 2800 | #define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR |
| 2801 | #define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR) |
| 2802 | #define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA) |
| 2803 | #define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST) |
| 2804 | #define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA) |
| 2805 | #define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST) |
| 2806 | |
| 2807 | /* Then the linear 2-byte formats. When naming these "Y" is used to |
| 2808 | * indicate a luminance (gray) channel. |
| 2809 | */ |
| 2810 | #define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR |
| 2811 | #define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA) |
| 2812 | #define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR) |
| 2813 | #define PNG_FORMAT_LINEAR_RGB_ALPHA \ |
| 2814 | (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA) |
| 2815 | |
| 2816 | /* With color-mapped formats the image data is one byte for each pixel, the byte |
| 2817 | * is an index into the color-map which is formatted as above. To obtain a |
| 2818 | * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP |
| 2819 | * to one of the above definitions, or you can use one of the definitions below. |
| 2820 | */ |
| 2821 | #define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP) |
| 2822 | #define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP) |
| 2823 | #define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP) |
| 2824 | #define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP) |
| 2825 | #define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP) |
| 2826 | #define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP) |
| 2827 | |
| 2828 | /* PNG_IMAGE macros |
| 2829 | * |
| 2830 | * These are convenience macros to derive information from a png_image |
| 2831 | * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the |
| 2832 | * actual image sample values - either the entries in the color-map or the |
| 2833 | * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values |
| 2834 | * for the pixels and will always return 1 for color-mapped formats. The |
| 2835 | * remaining macros return information about the rows in the image and the |
| 2836 | * complete image. |
| 2837 | * |
| 2838 | * NOTE: All the macros that take a png_image::format parameter are compile time |
| 2839 | * constants if the format parameter is, itself, a constant. Therefore these |
| 2840 | * macros can be used in array declarations and case labels where required. |
| 2841 | * Similarly the macros are also pre-processor constants (sizeof is not used) so |
| 2842 | * they can be used in #if tests. |
| 2843 | * |
| 2844 | * First the information about the samples. |
| 2845 | */ |
| 2846 | #define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\ |
| 2847 | (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1) |
| 2848 | /* Return the total number of channels in a given format: 1..4 */ |
| 2849 | |
| 2850 | #define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\ |
| 2851 | ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1) |
| 2852 | /* Return the size in bytes of a single component of a pixel or color-map |
| 2853 | * entry (as appropriate) in the image: 1 or 2. |
| 2854 | */ |
| 2855 | |
| 2856 | #define PNG_IMAGE_SAMPLE_SIZE(fmt)\ |
| 2857 | (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)) |
| 2858 | /* This is the size of the sample data for one sample. If the image is |
| 2859 | * color-mapped it is the size of one color-map entry (and image pixels are |
| 2860 | * one byte in size), otherwise it is the size of one image pixel. |
| 2861 | */ |
| 2862 | |
| 2863 | #define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\ |
| 2864 | (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256) |
| 2865 | /* The maximum size of the color-map required by the format expressed in a |
| 2866 | * count of components. This can be used to compile-time allocate a |
| 2867 | * color-map: |
| 2868 | * |
| 2869 | * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)]; |
| 2870 | * |
| 2871 | * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)]; |
| 2872 | * |
| 2873 | * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the |
| 2874 | * information from one of the png_image_begin_read_ APIs and dynamically |
| 2875 | * allocate the required memory. |
| 2876 | */ |
| 2877 | |
| 2878 | /* Corresponding information about the pixels */ |
| 2879 | #define PNG_IMAGE_PIXEL_(test,fmt)\ |
| 2880 | (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt)) |
| 2881 | |
| 2882 | #define PNG_IMAGE_PIXEL_CHANNELS(fmt)\ |
| 2883 | PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt) |
| 2884 | /* The number of separate channels (components) in a pixel; 1 for a |
| 2885 | * color-mapped image. |
| 2886 | */ |
| 2887 | |
| 2888 | #define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\ |
| 2889 | PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt) |
| 2890 | /* The size, in bytes, of each component in a pixel; 1 for a color-mapped |
| 2891 | * image. |
| 2892 | */ |
| 2893 | |
| 2894 | #define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt) |
| 2895 | /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */ |
| 2896 | |
| 2897 | /* Information about the whole row, or whole image */ |
| 2898 | #define PNG_IMAGE_ROW_STRIDE(image)\ |
| 2899 | (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width) |
| 2900 | /* Return the total number of components in a single row of the image; this |
| 2901 | * is the minimum 'row stride', the minimum count of components between each |
| 2902 | * row. For a color-mapped image this is the minimum number of bytes in a |
| 2903 | * row. |
| 2904 | * |
| 2905 | * WARNING: this macro overflows for some images with more than one component |
| 2906 | * and very large image widths. libpng will refuse to process an image where |
| 2907 | * this macro would overflow. |
| 2908 | */ |
| 2909 | |
| 2910 | #define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\ |
| 2911 | (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride)) |
| 2912 | /* Return the size, in bytes, of an image buffer given a png_image and a row |
| 2913 | * stride - the number of components to leave space for in each row. |
| 2914 | * |
| 2915 | * WARNING: this macro overflows a 32-bit integer for some large PNG images, |
| 2916 | * libpng will refuse to process an image where such an overflow would occur. |
| 2917 | */ |
| 2918 | |
| 2919 | #define PNG_IMAGE_SIZE(image)\ |
| 2920 | PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image)) |
| 2921 | /* Return the size, in bytes, of the image in memory given just a png_image; |
| 2922 | * the row stride is the minimum stride required for the image. |
| 2923 | */ |
| 2924 | |
| 2925 | #define PNG_IMAGE_COLORMAP_SIZE(image)\ |
| 2926 | (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries) |
| 2927 | /* Return the size, in bytes, of the color-map of this image. If the image |
| 2928 | * format is not a color-map format this will return a size sufficient for |
| 2929 | * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if |
| 2930 | * you don't want to allocate a color-map in this case. |
| 2931 | */ |
| 2932 | |
| 2933 | /* PNG_IMAGE_FLAG_* |
| 2934 | * |
| 2935 | * Flags containing additional information about the image are held in the |
| 2936 | * 'flags' field of png_image. |
| 2937 | */ |
| 2938 | #define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01 |
| 2939 | /* This indicates that the RGB values of the in-memory bitmap do not |
| 2940 | * correspond to the red, green and blue end-points defined by sRGB. |
| 2941 | */ |
| 2942 | |
| 2943 | #define PNG_IMAGE_FLAG_FAST 0x02 |
| 2944 | /* On write emphasise speed over compression; the resultant PNG file will be |
| 2945 | * larger but will be produced significantly faster, particular for large |
| 2946 | * images. Do not use this option for images which will be distributed, only |
| 2947 | * used it when producing intermediate files that will be read back in |
| 2948 | * repeatedly. For a typical 24-bit image the option will double the read |
| 2949 | * speed at the cost of increasing the image size by 25%, however for many |
| 2950 | * more compressible images the PNG file can be 10 times larger with only a |
| 2951 | * slight speed gain. |
| 2952 | */ |
| 2953 | |
| 2954 | #define PNG_IMAGE_FLAG_16BIT_sRGB 0x04 |
| 2955 | /* On read if the image is a 16-bit per component image and there is no gAMA |
| 2956 | * or sRGB chunk assume that the components are sRGB encoded. Notice that |
| 2957 | * images output by the simplified API always have gamma information; setting |
| 2958 | * this flag only affects the interpretation of 16-bit images from an |
| 2959 | * external source. It is recommended that the application expose this flag |
| 2960 | * to the user; the user can normally easily recognize the difference between |
| 2961 | * linear and sRGB encoding. This flag has no effect on write - the data |
| 2962 | * passed to the write APIs must have the correct encoding (as defined |
| 2963 | * above.) |
| 2964 | * |
| 2965 | * If the flag is not set (the default) input 16-bit per component data is |
| 2966 | * assumed to be linear. |
| 2967 | * |
| 2968 | * NOTE: the flag can only be set after the png_image_begin_read_ call, |
| 2969 | * because that call initializes the 'flags' field. |
| 2970 | */ |
| 2971 | |
| 2972 | #ifdef PNG_SIMPLIFIED_READ_SUPPORTED |
| 2973 | /* READ APIs |
| 2974 | * --------- |
| 2975 | * |
| 2976 | * The png_image passed to the read APIs must have been initialized by setting |
| 2977 | * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.) |
| 2978 | */ |
| 2979 | #ifdef PNG_STDIO_SUPPORTED |
| 2980 | PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image, |
| 2981 | const char *file_name)); |
| 2982 | /* The named file is opened for read and the image header is filled in |
| 2983 | * from the PNG header in the file. |
| 2984 | */ |
| 2985 | |
| 2986 | PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image, |
| 2987 | FILE* file)); |
| 2988 | /* The PNG header is read from the stdio FILE object. */ |
| 2989 | #endif /* STDIO */ |
| 2990 | |
| 2991 | PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image, |
| 2992 | png_const_voidp memory, size_t size)); |
| 2993 | /* The PNG header is read from the given memory buffer. */ |
| 2994 | |
| 2995 | PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image, |
| 2996 | png_const_colorp background, void *buffer, png_int_32 row_stride, |
| 2997 | void *colormap)); |
| 2998 | /* Finish reading the image into the supplied buffer and clean up the |
| 2999 | * png_image structure. |
| 3000 | * |
| 3001 | * row_stride is the step, in byte or 2-byte units as appropriate, |
| 3002 | * between adjacent rows. A positive stride indicates that the top-most row |
| 3003 | * is first in the buffer - the normal top-down arrangement. A negative |
| 3004 | * stride indicates that the bottom-most row is first in the buffer. |
| 3005 | * |
| 3006 | * background need only be supplied if an alpha channel must be removed from |
| 3007 | * a png_byte format and the removal is to be done by compositing on a solid |
| 3008 | * color; otherwise it may be NULL and any composition will be done directly |
| 3009 | * onto the buffer. The value is an sRGB color to use for the background, |
| 3010 | * for grayscale output the green channel is used. |
| 3011 | * |
| 3012 | * background must be supplied when an alpha channel must be removed from a |
| 3013 | * single byte color-mapped output format, in other words if: |
| 3014 | * |
| 3015 | * 1) The original format from png_image_begin_read_from_* had |
| 3016 | * PNG_FORMAT_FLAG_ALPHA set. |
| 3017 | * 2) The format set by the application does not. |
| 3018 | * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and |
| 3019 | * PNG_FORMAT_FLAG_LINEAR *not* set. |
| 3020 | * |
| 3021 | * For linear output removing the alpha channel is always done by compositing |
| 3022 | * on black and background is ignored. |
| 3023 | * |
| 3024 | * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must |
| 3025 | * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE. |
| 3026 | * image->colormap_entries will be updated to the actual number of entries |
| 3027 | * written to the colormap; this may be less than the original value. |
| 3028 | */ |
| 3029 | |
| 3030 | PNG_EXPORT(238, void, png_image_free, (png_imagep image)); |
| 3031 | /* Free any data allocated by libpng in image->opaque, setting the pointer to |
| 3032 | * NULL. May be called at any time after the structure is initialized. |
| 3033 | */ |
| 3034 | #endif /* SIMPLIFIED_READ */ |
| 3035 | |
| 3036 | #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED |
| 3037 | /* WRITE APIS |
| 3038 | * ---------- |
| 3039 | * For write you must initialize a png_image structure to describe the image to |
| 3040 | * be written. To do this use memset to set the whole structure to 0 then |
| 3041 | * initialize fields describing your image. |
| 3042 | * |
| 3043 | * version: must be set to PNG_IMAGE_VERSION |
| 3044 | * opaque: must be initialized to NULL |
| 3045 | * width: image width in pixels |
| 3046 | * height: image height in rows |
| 3047 | * format: the format of the data (image and color-map) you wish to write |
| 3048 | * flags: set to 0 unless one of the defined flags applies; set |
| 3049 | * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB |
| 3050 | * values do not correspond to the colors in sRGB. |
| 3051 | * colormap_entries: set to the number of entries in the color-map (0 to 256) |
| 3052 | */ |
| 3053 | #ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED |
| 3054 | PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image, |
| 3055 | const char *file, int convert_to_8bit, const void *buffer, |
| 3056 | png_int_32 row_stride, const void *colormap)); |
| 3057 | /* Write the image to the named file. */ |
| 3058 | |
| 3059 | PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file, |
| 3060 | int convert_to_8_bit, const void *buffer, png_int_32 row_stride, |
| 3061 | const void *colormap)); |
| 3062 | /* Write the image to the given (FILE*). */ |
| 3063 | #endif /* SIMPLIFIED_WRITE_STDIO */ |
| 3064 | |
| 3065 | /* With all write APIs if image is in one of the linear formats with 16-bit |
| 3066 | * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG |
| 3067 | * gamma encoded according to the sRGB specification, otherwise a 16-bit linear |
| 3068 | * encoded PNG file is written. |
| 3069 | * |
| 3070 | * With color-mapped data formats the colormap parameter point to a color-map |
| 3071 | * with at least image->colormap_entries encoded in the specified format. If |
| 3072 | * the format is linear the written PNG color-map will be converted to sRGB |
| 3073 | * regardless of the convert_to_8_bit flag. |
| 3074 | * |
| 3075 | * With all APIs row_stride is handled as in the read APIs - it is the spacing |
| 3076 | * from one row to the next in component sized units (1 or 2 bytes) and if |
| 3077 | * negative indicates a bottom-up row layout in the buffer. If row_stride is |
| 3078 | * zero, libpng will calculate it for you from the image width and number of |
| 3079 | * channels. |
| 3080 | * |
| 3081 | * Note that the write API does not support interlacing, sub-8-bit pixels or |
| 3082 | * most ancillary chunks. If you need to write text chunks (e.g. for copyright |
| 3083 | * notices) you need to use one of the other APIs. |
| 3084 | */ |
| 3085 | |
| 3086 | PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory, |
| 3087 | png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8_bit, |
| 3088 | const void *buffer, png_int_32 row_stride, const void *colormap)); |
| 3089 | /* Write the image to the given memory buffer. The function both writes the |
| 3090 | * whole PNG data stream to *memory and updates *memory_bytes with the count |
| 3091 | * of bytes written. |
| 3092 | * |
| 3093 | * 'memory' may be NULL. In this case *memory_bytes is not read however on |
| 3094 | * success the number of bytes which would have been written will still be |
| 3095 | * stored in *memory_bytes. On failure *memory_bytes will contain 0. |
| 3096 | * |
| 3097 | * If 'memory' is not NULL it must point to memory[*memory_bytes] of |
| 3098 | * writeable memory. |
| 3099 | * |
| 3100 | * If the function returns success memory[*memory_bytes] (if 'memory' is not |
| 3101 | * NULL) contains the written PNG data. *memory_bytes will always be less |
| 3102 | * than or equal to the original value. |
| 3103 | * |
| 3104 | * If the function returns false and *memory_bytes was not changed an error |
| 3105 | * occurred during write. If *memory_bytes was changed, or is not 0 if |
| 3106 | * 'memory' was NULL, the write would have succeeded but for the memory |
| 3107 | * buffer being too small. *memory_bytes contains the required number of |
| 3108 | * bytes and will be bigger that the original value. |
| 3109 | */ |
| 3110 | |
| 3111 | #define png_image_write_get_memory_size(image, size, convert_to_8_bit, buffer,\ |
| 3112 | row_stride, colormap)\ |
| 3113 | png_image_write_to_memory(&(image), 0, &(size), convert_to_8_bit, buffer,\ |
| 3114 | row_stride, colormap) |
| 3115 | /* Return the amount of memory in 'size' required to compress this image. |
| 3116 | * The png_image structure 'image' must be filled in as in the above |
| 3117 | * function and must not be changed before the actual write call, the buffer |
| 3118 | * and all other parameters must also be identical to that in the final |
| 3119 | * write call. The 'size' variable need not be initialized. |
| 3120 | * |
| 3121 | * NOTE: the macro returns true/false, if false is returned 'size' will be |
| 3122 | * set to zero and the write failed and probably will fail if tried again. |
| 3123 | */ |
| 3124 | |
| 3125 | /* You can pre-allocate the buffer by making sure it is of sufficient size |
| 3126 | * regardless of the amount of compression achieved. The buffer size will |
| 3127 | * always be bigger than the original image and it will never be filled. The |
| 3128 | * following macros are provided to assist in allocating the buffer. |
| 3129 | */ |
| 3130 | #define PNG_IMAGE_DATA_SIZE(image) (PNG_IMAGE_SIZE(image)+(image).height) |
| 3131 | /* The number of uncompressed bytes in the PNG byte encoding of the image; |
| 3132 | * uncompressing the PNG IDAT data will give this number of bytes. |
| 3133 | * |
| 3134 | * NOTE: while PNG_IMAGE_SIZE cannot overflow for an image in memory this |
| 3135 | * macro can because of the extra bytes used in the PNG byte encoding. You |
| 3136 | * need to avoid this macro if your image size approaches 2^30 in width or |
| 3137 | * height. The same goes for the remainder of these macros; they all produce |
| 3138 | * bigger numbers than the actual in-memory image size. |
| 3139 | */ |
| 3140 | #ifndef PNG_ZLIB_MAX_SIZE |
| 3141 | # define PNG_ZLIB_MAX_SIZE(b) ((b)+(((b)+7U)>>3)+(((b)+63U)>>6)+11U) |
| 3142 | /* An upper bound on the number of compressed bytes given 'b' uncompressed |
| 3143 | * bytes. This is based on deflateBounds() in zlib; different |
| 3144 | * implementations of zlib compression may conceivably produce more data so |
| 3145 | * if your zlib implementation is not zlib itself redefine this macro |
| 3146 | * appropriately. |
| 3147 | */ |
| 3148 | #endif |
| 3149 | |
| 3150 | #define PNG_IMAGE_COMPRESSED_SIZE_MAX(image)\ |
| 3151 | PNG_ZLIB_MAX_SIZE((png_alloc_size_t)PNG_IMAGE_DATA_SIZE(image)) |
| 3152 | /* An upper bound on the size of the data in the PNG IDAT chunks. */ |
| 3153 | |
| 3154 | #define PNG_IMAGE_PNG_SIZE_MAX_(image, image_size)\ |
| 3155 | ((8U/*sig*/+25U/*IHDR*/+16U/*gAMA*/+44U/*cHRM*/+12U/*IEND*/+\ |
| 3156 | (((image).format&PNG_FORMAT_FLAG_COLORMAP)?/*colormap: PLTE, tRNS*/\ |
| 3157 | 12U+3U*(image).colormap_entries/*PLTE data*/+\ |
| 3158 | (((image).format&PNG_FORMAT_FLAG_ALPHA)?\ |
| 3159 | 12U/*tRNS*/+(image).colormap_entries:0U):0U)+\ |
| 3160 | 12U)+(12U*((image_size)/PNG_ZBUF_SIZE))/*IDAT*/+(image_size)) |
| 3161 | /* A helper for the following macro; if your compiler cannot handle the |
| 3162 | * following macro use this one with the result of |
| 3163 | * PNG_IMAGE_COMPRESSED_SIZE_MAX(image) as the second argument (most |
| 3164 | * compilers should handle this just fine.) |
| 3165 | */ |
| 3166 | |
| 3167 | #define PNG_IMAGE_PNG_SIZE_MAX(image)\ |
| 3168 | PNG_IMAGE_PNG_SIZE_MAX_(image, PNG_IMAGE_COMPRESSED_SIZE_MAX(image)) |
| 3169 | /* An upper bound on the total length of the PNG data stream for 'image'. |
| 3170 | * The result is of type png_alloc_size_t, on 32-bit systems this may |
| 3171 | * overflow even though PNG_IMAGE_DATA_SIZE does not overflow; the write will |
| 3172 | * run out of buffer space but return a corrected size which should work. |
| 3173 | */ |
| 3174 | #endif /* SIMPLIFIED_WRITE */ |
| 3175 | /******************************************************************************* |
| 3176 | * END OF SIMPLIFIED API |
| 3177 | ******************************************************************************/ |
| 3178 | #endif /* SIMPLIFIED_{READ|WRITE} */ |
| 3179 | |
| 3180 | /******************************************************************************* |
| 3181 | * Section 6: IMPLEMENTATION OPTIONS |
| 3182 | ******************************************************************************* |
| 3183 | * |
| 3184 | * Support for arbitrary implementation-specific optimizations. The API allows |
| 3185 | * particular options to be turned on or off. 'Option' is the number of the |
| 3186 | * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given |
| 3187 | * by the PNG_OPTION_ defines below. |
| 3188 | * |
| 3189 | * HARDWARE: normally hardware capabilities, such as the Intel SSE instructions, |
| 3190 | * are detected at run time, however sometimes it may be impossible |
| 3191 | * to do this in user mode, in which case it is necessary to discover |
| 3192 | * the capabilities in an OS specific way. Such capabilities are |
| 3193 | * listed here when libpng has support for them and must be turned |
| 3194 | * ON by the application if present. |
| 3195 | * |
| 3196 | * SOFTWARE: sometimes software optimizations actually result in performance |
| 3197 | * decrease on some architectures or systems, or with some sets of |
| 3198 | * PNG images. 'Software' options allow such optimizations to be |
| 3199 | * selected at run time. |
| 3200 | */ |
| 3201 | #ifdef PNG_SET_OPTION_SUPPORTED |
| 3202 | #ifdef PNG_ARM_NEON_API_SUPPORTED |
| 3203 | # define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */ |
| 3204 | #endif |
| 3205 | #define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */ |
| 3206 | #define PNG_SKIP_sRGB_CHECK_PROFILE 4 /* SOFTWARE: Check ICC profile for sRGB */ |
| 3207 | #ifdef PNG_MIPS_MSA_API_SUPPORTED |
| 3208 | # define PNG_MIPS_MSA 6 /* HARDWARE: MIPS Msa SIMD instructions supported */ |
| 3209 | #endif |
| 3210 | #define PNG_IGNORE_ADLER32 8 |
| 3211 | #ifdef PNG_POWERPC_VSX_API_SUPPORTED |
| 3212 | # define PNG_POWERPC_VSX 10 /* HARDWARE: PowerPC VSX SIMD instructions supported */ |
| 3213 | #endif |
| 3214 | #define PNG_OPTION_NEXT 12 /* Next option - numbers must be even */ |
| 3215 | |
| 3216 | /* Return values: NOTE: there are four values and 'off' is *not* zero */ |
| 3217 | #define PNG_OPTION_UNSET 0 /* Unset - defaults to off */ |
| 3218 | #define PNG_OPTION_INVALID 1 /* Option number out of range */ |
| 3219 | #define PNG_OPTION_OFF 2 |
| 3220 | #define PNG_OPTION_ON 3 |
| 3221 | |
| 3222 | PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option, |
| 3223 | int onoff)); |
| 3224 | #endif /* SET_OPTION */ |
| 3225 | |
| 3226 | /******************************************************************************* |
| 3227 | * END OF HARDWARE AND SOFTWARE OPTIONS |
| 3228 | ******************************************************************************/ |
| 3229 | |
| 3230 | /* Maintainer: Put new public prototypes here ^, in libpng.3, in project |
| 3231 | * defs, and in scripts/symbols.def. |
| 3232 | */ |
| 3233 | |
| 3234 | /* The last ordinal number (this is the *last* one already used; the next |
| 3235 | * one to use is one more than this.) |
| 3236 | */ |
| 3237 | #ifdef PNG_EXPORT_LAST_ORDINAL |
| 3238 | PNG_EXPORT_LAST_ORDINAL(249); |
| 3239 | #endif |
| 3240 | |
| 3241 | #ifdef __cplusplus |
| 3242 | } |
| 3243 | #endif |
| 3244 | |
| 3245 | #endif /* PNG_VERSION_INFO_ONLY */ |
| 3246 | /* Do not put anything past this line */ |
| 3247 | #endif /* PNG_H */ |
| 3248 |
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