1 /* png.h - header file for PNG reference library
3 * libpng version 1.2.8 - December 3, 2004
4 * Copyright (c) 1998-2004 Glenn Randers-Pehrson
5 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
6 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
8 * Authors and maintainers:
9 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
10 * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
11 * libpng versions 0.97, January 1998, through 1.2.8 - December 3, 2004: Glenn
12 * See also "Contributing Authors", below.
14 * Note about libpng version numbers:
16 * Due to various miscommunications, unforeseen code incompatibilities
17 * and occasional factors outside the authors' control, version numbering
18 * on the library has not always been consistent and straightforward.
19 * The following table summarizes matters since version 0.89c, which was
20 * the first widely used release:
22 * source png.h png.h shared-lib
23 * version string int version
24 * ------- ------ ----- ----------
25 * 0.89c "1.0 beta 3" 0.89 89 1.0.89
26 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]
27 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]
28 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]
29 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]
30 * 0.97c 0.97 97 2.0.97
33 * 0.99a-m 0.99 99 2.0.99
34 * 1.00 1.00 100 2.1.0 [100 should be 10000]
35 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]
36 * 1.0.1 png.h string is 10001 2.1.0
37 * 1.0.1a-e identical to the 10002 from here on, the shared library
38 * 1.0.2 source version) 10002 is 2.V where V is the source code
39 * 1.0.2a-b 10003 version, except as noted.
44 * 1.0.5 (+ 2 patches) 10005
46 * 1.0.5e-r 10100 (not source compatible)
47 * 1.0.5s-v 10006 (not binary compatible)
48 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible)
49 * 1.0.6d-f 10007 (still binary incompatible)
51 * 1.0.6h 10007 10.6h (testing xy.z so-numbering)
53 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)
54 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)
55 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)
56 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)
57 * 1.0.7 1 10007 (still compatible)
58 * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4
59 * 1.0.8rc1 1 10008 2.1.0.8rc1
60 * 1.0.8 1 10008 2.1.0.8
61 * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6
62 * 1.0.9rc1 1 10009 2.1.0.9rc1
63 * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10
64 * 1.0.9rc2 1 10009 2.1.0.9rc2
65 * 1.0.9 1 10009 2.1.0.9
66 * 1.0.10beta1 1 10010 2.1.0.10beta1
67 * 1.0.10rc1 1 10010 2.1.0.10rc1
68 * 1.0.10 1 10010 2.1.0.10
69 * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3
70 * 1.0.11rc1 1 10011 2.1.0.11rc1
71 * 1.0.11 1 10011 2.1.0.11
72 * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2
73 * 1.0.12rc1 2 10012 2.1.0.12rc1
74 * 1.0.12 2 10012 2.1.0.12
75 * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned)
76 * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2
77 * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5
78 * 1.2.0rc1 3 10200 3.1.2.0rc1
79 * 1.2.0 3 10200 3.1.2.0
80 * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4
81 * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2
82 * 1.2.1 3 10201 3.1.2.1
83 * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6
84 * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1
85 * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1
86 * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1
87 * 1.0.13 10 10013 10.so.0.1.0.13
88 * 1.2.2 12 10202 12.so.0.1.2.2
89 * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6
90 * 1.2.3 12 10203 12.so.0.1.2.3
91 * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3
92 * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1
93 * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1
94 * 1.0.14 10 10014 10.so.0.1.0.14
95 * 1.2.4 13 10204 12.so.0.1.2.4
96 * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2
97 * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3
98 * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3
99 * 1.0.15 10 10015 10.so.0.1.0.15
100 * 1.2.5 13 10205 12.so.0.1.2.5
101 * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4
102 * 1.0.16 10 10016 10.so.0.1.0.16
103 * 1.2.6 13 10206 12.so.0.1.2.6
104 * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2
105 * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1
106 * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1
107 * 1.0.17 10 10017 12.so.0.1.0.17
108 * 1.2.7 13 10207 12.so.0.1.2.7
109 * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5
110 * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5
111 * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5
112 * 1.0.18 10 10018 12.so.0.1.0.18
113 * 1.2.8 13 10208 12.so.0.1.2.8
115 * Henceforth the source version will match the shared-library major
116 * and minor numbers; the shared-library major version number will be
117 * used for changes in backward compatibility, as it is intended. The
118 * PNG_LIBPNG_VER macro, which is not used within libpng but is available
119 * for applications, is an unsigned integer of the form xyyzz corresponding
120 * to the source version x.y.z (leading zeros in y and z). Beta versions
121 * were given the previous public release number plus a letter, until
122 * version 1.0.6j; from then on they were given the upcoming public
123 * release number plus "betaNN" or "rcN".
125 * Binary incompatibility exists only when applications make direct access
126 * to the info_ptr or png_ptr members through png.h, and the compiled
127 * application is loaded with a different version of the library.
129 * DLLNUM will change each time there are forward or backward changes
130 * in binary compatibility (e.g., when a new feature is added).
132 * See libpng.txt or libpng.3 for more information. The PNG specification
133 * is available as a W3C Recommendation and as an ISO Specification,
134 * <http://www.w3.org/TR/2003/REC-PNG-20031110/
138 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
140 * If you modify libpng you may insert additional notices immediately following
143 * libpng versions 1.2.6, August 15, 2004, through 1.2.8, December 3, 2004, are
144 * Copyright (c) 2004 Glenn Randers-Pehrson, and are
145 * distributed according to the same disclaimer and license as libpng-1.2.5
146 * with the following individual added to the list of Contributing Authors:
150 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
151 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
152 * distributed according to the same disclaimer and license as libpng-1.0.6
153 * with the following individuals added to the list of Contributing Authors:
155 * Simon-Pierre Cadieux
159 * and with the following additions to the disclaimer:
161 * There is no warranty against interference with your enjoyment of the
162 * library or against infringement. There is no warranty that our
163 * efforts or the library will fulfill any of your particular purposes
164 * or needs. This library is provided with all faults, and the entire
165 * risk of satisfactory quality, performance, accuracy, and effort is with
168 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
169 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
170 * distributed according to the same disclaimer and license as libpng-0.96,
171 * with the following individuals added to the list of Contributing Authors:
174 * Glenn Randers-Pehrson
177 * libpng versions 0.89, June 1996, through 0.96, May 1997, are
178 * Copyright (c) 1996, 1997 Andreas Dilger
179 * Distributed according to the same disclaimer and license as libpng-0.88,
180 * with the following individuals added to the list of Contributing Authors:
189 * libpng versions 0.5, May 1995, through 0.88, January 1996, are
190 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
192 * For the purposes of this copyright and license, "Contributing Authors"
193 * is defined as the following set of individuals:
201 * The PNG Reference Library is supplied "AS IS". The Contributing Authors
202 * and Group 42, Inc. disclaim all warranties, expressed or implied,
203 * including, without limitation, the warranties of merchantability and of
204 * fitness for any purpose. The Contributing Authors and Group 42, Inc.
205 * assume no liability for direct, indirect, incidental, special, exemplary,
206 * or consequential damages, which may result from the use of the PNG
207 * Reference Library, even if advised of the possibility of such damage.
209 * Permission is hereby granted to use, copy, modify, and distribute this
210 * source code, or portions hereof, for any purpose, without fee, subject
211 * to the following restrictions:
213 * 1. The origin of this source code must not be misrepresented.
215 * 2. Altered versions must be plainly marked as such and
216 * must not be misrepresented as being the original source.
218 * 3. This Copyright notice may not be removed or altered from
219 * any source or altered source distribution.
221 * The Contributing Authors and Group 42, Inc. specifically permit, without
222 * fee, and encourage the use of this source code as a component to
223 * supporting the PNG file format in commercial products. If you use this
224 * source code in a product, acknowledgment is not required but would be
229 * A "png_get_copyright" function is available, for convenient use in "about"
230 * boxes and the like:
232 * printf("%s",png_get_copyright(NULL));
234 * Also, the PNG logo (in PNG format, of course) is supplied in the
235 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
239 * Libpng is OSI Certified Open Source Software. OSI Certified is a
240 * certification mark of the Open Source Initiative.
244 * The contributing authors would like to thank all those who helped
245 * with testing, bug fixes, and patience. This wouldn't have been
246 * possible without all of you.
248 * Thanks to Frank J. T. Wojcik for helping with the documentation.
252 * Y2K compliance in libpng:
253 * =========================
257 * Since the PNG Development group is an ad-hoc body, we can't make
258 * an official declaration.
260 * This is your unofficial assurance that libpng from version 0.71 and
261 * upward through 1.2.8 are Y2K compliant. It is my belief that earlier
262 * versions were also Y2K compliant.
264 * Libpng only has three year fields. One is a 2-byte unsigned integer
265 * that will hold years up to 65535. The other two hold the date in text
266 * format, and will hold years up to 9999.
269 * "png_uint_16 year" in png_time_struct.
272 * "png_charp time_buffer" in png_struct and
273 * "near_time_buffer", which is a local character string in png.c.
275 * There are seven time-related functions:
276 * png.c: png_convert_to_rfc_1123() in png.c
277 * (formerly png_convert_to_rfc_1152() in error)
278 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
279 * png_convert_from_time_t() in pngwrite.c
280 * png_get_tIME() in pngget.c
281 * png_handle_tIME() in pngrutil.c, called in pngread.c
282 * png_set_tIME() in pngset.c
283 * png_write_tIME() in pngwutil.c, called in pngwrite.c
285 * All handle dates properly in a Y2K environment. The
286 * png_convert_from_time_t() function calls gmtime() to convert from system
287 * clock time, which returns (year - 1900), which we properly convert to
288 * the full 4-digit year. There is a possibility that applications using
289 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
290 * function, or that they are incorrectly passing only a 2-digit year
291 * instead of "year - 1900" into the png_convert_from_struct_tm() function,
292 * but this is not under our control. The libpng documentation has always
293 * stated that it works with 4-digit years, and the APIs have been
294 * documented as such.
296 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
297 * integer to hold the year, and can hold years as large as 65535.
299 * zlib, upon which libpng depends, is also Y2K compliant. It contains
300 * no date-related code.
302 * Glenn Randers-Pehrson
304 * PNG Development Group
310 /* This is not the place to learn how to use libpng. The file libpng.txt
311 * describes how to use libpng, and the file example.c summarizes it
312 * with some code on which to build. This file is useful for looking
313 * at the actual function definitions and structure components.
316 /* Version information for png.h - this should match the version in png.c */
317 #define PNG_LIBPNG_VER_STRING "1.2.8"
318 #define PNG_HEADER_VERSION_STRING \
319 " libpng version 1.2.8 - December 3, 2004 (header)\n"
321 #define PNG_LIBPNG_VER_SONUM 0
322 #define PNG_LIBPNG_VER_DLLNUM 13
324 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
325 #define PNG_LIBPNG_VER_MAJOR 1
326 #define PNG_LIBPNG_VER_MINOR 2
327 #define PNG_LIBPNG_VER_RELEASE 8
328 /* This should match the numeric part of the final component of
329 * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
331 #define PNG_LIBPNG_VER_BUILD 0
334 #define PNG_LIBPNG_BUILD_ALPHA 1
335 #define PNG_LIBPNG_BUILD_BETA 2
336 #define PNG_LIBPNG_BUILD_RC 3
337 #define PNG_LIBPNG_BUILD_STABLE 4
338 #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
340 /* Release-Specific Flags */
341 #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with
342 PNG_LIBPNG_BUILD_STABLE only */
343 #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
344 PNG_LIBPNG_BUILD_SPECIAL */
345 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
346 PNG_LIBPNG_BUILD_PRIVATE */
348 #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
350 /* Careful here. At one time, Guy wanted to use 082, but that would be octal.
351 * We must not include leading zeros.
352 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
353 * version 1.0.0 was mis-numbered 100 instead of 10000). From
354 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release */
355 #define PNG_LIBPNG_VER 10208 /* 1.2.8 */
357 #ifndef PNG_VERSION_INFO_ONLY
358 /* include the compression library's header */
362 /* include all user configurable info, including optional assembler routines */
366 * Added at libpng-1.2.8 */
367 /* Ref MSDN: Private as priority over Special
368 * VS_FF_PRIVATEBUILD File *was not* built using standard release
369 * procedures. If this value is given, the StringFileInfo block must
370 * contain a PrivateBuild string.
372 * VS_FF_SPECIALBUILD File *was* built by the original company using
373 * standard release procedures but is a variation of the standard
374 * file of the same version number. If this value is given, the
375 * StringFileInfo block must contain a SpecialBuild string.
378 #if defined(PNG_USER_PRIVATEBUILD)
379 # define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE | \
380 PNG_LIBPNG_BUILD_PRIVATE
382 # if defined(PNG_LIBPNG_SPECIALBUILD)
383 # define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE | \
384 PNG_LIBPNG_BUILD_SPECIAL
386 # define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE
390 #ifndef PNG_VERSION_INFO_ONLY
392 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
395 #endif /* __cplusplus */
397 /* This file is arranged in several sections. The first section contains
398 * structure and type definitions. The second section contains the external
399 * library functions, while the third has the internal library functions,
400 * which applications aren't expected to use directly.
403 #ifndef PNG_NO_TYPECAST_NULL
404 #define int_p_NULL (int *)NULL
405 #define png_bytep_NULL (png_bytep)NULL
406 #define png_bytepp_NULL (png_bytepp)NULL
407 #define png_doublep_NULL (png_doublep)NULL
408 #define png_error_ptr_NULL (png_error_ptr)NULL
409 #define png_flush_ptr_NULL (png_flush_ptr)NULL
410 #define png_free_ptr_NULL (png_free_ptr)NULL
411 #define png_infopp_NULL (png_infopp)NULL
412 #define png_malloc_ptr_NULL (png_malloc_ptr)NULL
413 #define png_read_status_ptr_NULL (png_read_status_ptr)NULL
414 #define png_rw_ptr_NULL (png_rw_ptr)NULL
415 #define png_structp_NULL (png_structp)NULL
416 #define png_uint_16p_NULL (png_uint_16p)NULL
417 #define png_voidp_NULL (png_voidp)NULL
418 #define png_write_status_ptr_NULL (png_write_status_ptr)NULL
420 #define int_p_NULL NULL
421 #define png_bytep_NULL NULL
422 #define png_bytepp_NULL NULL
423 #define png_doublep_NULL NULL
424 #define png_error_ptr_NULL NULL
425 #define png_flush_ptr_NULL NULL
426 #define png_free_ptr_NULL NULL
427 #define png_infopp_NULL NULL
428 #define png_malloc_ptr_NULL NULL
429 #define png_read_status_ptr_NULL NULL
430 #define png_rw_ptr_NULL NULL
431 #define png_structp_NULL NULL
432 #define png_uint_16p_NULL NULL
433 #define png_voidp_NULL NULL
434 #define png_write_status_ptr_NULL NULL
437 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
438 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
439 /* Version information for C files, stored in png.c. This had better match
442 #ifdef PNG_USE_GLOBAL_ARRAYS
443 PNG_EXPORT_VAR (const char) png_libpng_ver[18];
444 /* need room for 99.99.99beta99z */
446 #define png_libpng_ver png_get_header_ver(NULL)
449 #ifdef PNG_USE_GLOBAL_ARRAYS
450 /* This was removed in version 1.0.5c */
451 /* Structures to facilitate easy interlacing. See png.c for more details */
452 PNG_EXPORT_VAR (const int FARDATA) png_pass_start[7];
453 PNG_EXPORT_VAR (const int FARDATA) png_pass_inc[7];
454 PNG_EXPORT_VAR (const int FARDATA) png_pass_ystart[7];
455 PNG_EXPORT_VAR (const int FARDATA) png_pass_yinc[7];
456 PNG_EXPORT_VAR (const int FARDATA) png_pass_mask[7];
457 PNG_EXPORT_VAR (const int FARDATA) png_pass_dsp_mask[7];
458 #ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
459 PNG_EXPORT_VAR (const int FARDATA) png_pass_width[7];
461 /* This isn't currently used. If you need it, see png.c for more details.
462 PNG_EXPORT_VAR (const int FARDATA) png_pass_height[7];
466 #endif /* PNG_NO_EXTERN */
468 /* Three color definitions. The order of the red, green, and blue, (and the
469 * exact size) is not important, although the size of the fields need to
470 * be png_byte or png_uint_16 (as defined below).
472 typedef struct png_color_struct
478 typedef png_color FAR * png_colorp;
479 typedef png_color FAR * FAR * png_colorpp;
481 typedef struct png_color_16_struct
483 png_byte index; /* used for palette files */
484 png_uint_16 red; /* for use in red green blue files */
487 png_uint_16 gray; /* for use in grayscale files */
489 typedef png_color_16 FAR * png_color_16p;
490 typedef png_color_16 FAR * FAR * png_color_16pp;
492 typedef struct png_color_8_struct
494 png_byte red; /* for use in red green blue files */
497 png_byte gray; /* for use in grayscale files */
498 png_byte alpha; /* for alpha channel files */
500 typedef png_color_8 FAR * png_color_8p;
501 typedef png_color_8 FAR * FAR * png_color_8pp;
504 * The following two structures are used for the in-core representation
507 typedef struct png_sPLT_entry_struct
513 png_uint_16 frequency;
515 typedef png_sPLT_entry FAR * png_sPLT_entryp;
516 typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
518 /* When the depth of the sPLT palette is 8 bits, the color and alpha samples
519 * occupy the LSB of their respective members, and the MSB of each member
520 * is zero-filled. The frequency member always occupies the full 16 bits.
523 typedef struct png_sPLT_struct
525 png_charp name; /* palette name */
526 png_byte depth; /* depth of palette samples */
527 png_sPLT_entryp entries; /* palette entries */
528 png_int_32 nentries; /* number of palette entries */
530 typedef png_sPLT_t FAR * png_sPLT_tp;
531 typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
533 #ifdef PNG_TEXT_SUPPORTED
534 /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
535 * and whether that contents is compressed or not. The "key" field
536 * points to a regular zero-terminated C string. The "text", "lang", and
537 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
538 * However, the * structure returned by png_get_text() will always contain
539 * regular zero-terminated C strings (possibly empty), never NULL pointers,
540 * so they can be safely used in printf() and other string-handling functions.
542 typedef struct png_text_struct
544 int compression; /* compression value:
549 png_charp key; /* keyword, 1-79 character description of "text" */
550 png_charp text; /* comment, may be an empty string (ie "")
552 png_size_t text_length; /* length of the text string */
553 #ifdef PNG_iTXt_SUPPORTED
554 png_size_t itxt_length; /* length of the itxt string */
555 png_charp lang; /* language code, 0-79 characters
557 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
558 chars or a NULL pointer */
561 typedef png_text FAR * png_textp;
562 typedef png_text FAR * FAR * png_textpp;
565 /* Supported compression types for text in PNG files (tEXt, and zTXt).
566 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
567 #define PNG_TEXT_COMPRESSION_NONE_WR -3
568 #define PNG_TEXT_COMPRESSION_zTXt_WR -2
569 #define PNG_TEXT_COMPRESSION_NONE -1
570 #define PNG_TEXT_COMPRESSION_zTXt 0
571 #define PNG_ITXT_COMPRESSION_NONE 1
572 #define PNG_ITXT_COMPRESSION_zTXt 2
573 #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
575 /* png_time is a way to hold the time in an machine independent way.
576 * Two conversions are provided, both from time_t and struct tm. There
577 * is no portable way to convert to either of these structures, as far
578 * as I know. If you know of a portable way, send it to me. As a side
579 * note - PNG has always been Year 2000 compliant!
581 typedef struct png_time_struct
583 png_uint_16 year; /* full year, as in, 1995 */
584 png_byte month; /* month of year, 1 - 12 */
585 png_byte day; /* day of month, 1 - 31 */
586 png_byte hour; /* hour of day, 0 - 23 */
587 png_byte minute; /* minute of hour, 0 - 59 */
588 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
590 typedef png_time FAR * png_timep;
591 typedef png_time FAR * FAR * png_timepp;
593 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
594 /* png_unknown_chunk is a structure to hold queued chunks for which there is
595 * no specific support. The idea is that we can use this to queue
596 * up private chunks for output even though the library doesn't actually
597 * know about their semantics.
599 typedef struct png_unknown_chunk_t
605 /* libpng-using applications should NOT directly modify this byte. */
606 png_byte location; /* mode of operation at read time */
609 typedef png_unknown_chunk FAR * png_unknown_chunkp;
610 typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
613 /* png_info is a structure that holds the information in a PNG file so
614 * that the application can find out the characteristics of the image.
615 * If you are reading the file, this structure will tell you what is
616 * in the PNG file. If you are writing the file, fill in the information
617 * you want to put into the PNG file, then call png_write_info().
618 * The names chosen should be very close to the PNG specification, so
619 * consult that document for information about the meaning of each field.
621 * With libpng < 0.95, it was only possible to directly set and read the
622 * the values in the png_info_struct, which meant that the contents and
623 * order of the values had to remain fixed. With libpng 0.95 and later,
624 * however, there are now functions that abstract the contents of
625 * png_info_struct from the application, so this makes it easier to use
626 * libpng with dynamic libraries, and even makes it possible to use
627 * libraries that don't have all of the libpng ancillary chunk-handing
630 * In any case, the order of the parameters in png_info_struct should NOT
631 * be changed for as long as possible to keep compatibility with applications
632 * that use the old direct-access method with png_info_struct.
634 * The following members may have allocated storage attached that should be
635 * cleaned up before the structure is discarded: palette, trans, text,
636 * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
637 * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
638 * are automatically freed when the info structure is deallocated, if they were
639 * allocated internally by libpng. This behavior can be changed by means
640 * of the png_data_freer() function.
642 * More allocation details: all the chunk-reading functions that
643 * change these members go through the corresponding png_set_*
644 * functions. A function to clear these members is available: see
645 * png_free_data(). The png_set_* functions do not depend on being
646 * able to point info structure members to any of the storage they are
647 * passed (they make their own copies), EXCEPT that the png_set_text
648 * functions use the same storage passed to them in the text_ptr or
649 * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
650 * functions do not make their own copies.
652 typedef struct png_info_struct
654 /* the following are necessary for every PNG file */
655 png_uint_32 width; /* width of image in pixels (from IHDR) */
656 png_uint_32 height; /* height of image in pixels (from IHDR) */
657 png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
658 png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
659 png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
660 png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
661 png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
662 png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
663 png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
664 /* The following three should have been named *_method not *_type */
665 png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
666 png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
667 png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
669 /* The following is informational only on read, and not used on writes. */
670 png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
671 png_byte pixel_depth; /* number of bits per pixel */
672 png_byte spare_byte; /* to align the data, and for future use */
673 png_byte signature[8]; /* magic bytes read by libpng from start of file */
675 /* The rest of the data is optional. If you are reading, check the
676 * valid field to see if the information in these are valid. If you
677 * are writing, set the valid field to those chunks you want written,
678 * and initialize the appropriate fields below.
681 #if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
682 /* The gAMA chunk describes the gamma characteristics of the system
683 * on which the image was created, normally in the range [1.0, 2.5].
684 * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
686 float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
689 #if defined(PNG_sRGB_SUPPORTED)
691 /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
692 png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
695 #if defined(PNG_TEXT_SUPPORTED)
696 /* The tEXt, and zTXt chunks contain human-readable textual data in
697 * uncompressed, compressed, and optionally compressed forms, respectively.
698 * The data in "text" is an array of pointers to uncompressed,
699 * null-terminated C strings. Each chunk has a keyword that describes the
700 * textual data contained in that chunk. Keywords are not required to be
701 * unique, and the text string may be empty. Any number of text chunks may
704 int num_text; /* number of comments read/to write */
705 int max_text; /* current size of text array */
706 png_textp text; /* array of comments read/to write */
707 #endif /* PNG_TEXT_SUPPORTED */
709 #if defined(PNG_tIME_SUPPORTED)
710 /* The tIME chunk holds the last time the displayed image data was
711 * modified. See the png_time struct for the contents of this struct.
716 #if defined(PNG_sBIT_SUPPORTED)
717 /* The sBIT chunk specifies the number of significant high-order bits
718 * in the pixel data. Values are in the range [1, bit_depth], and are
719 * only specified for the channels in the pixel data. The contents of
720 * the low-order bits is not specified. Data is valid if
721 * (valid & PNG_INFO_sBIT) is non-zero.
723 png_color_8 sig_bit; /* significant bits in color channels */
726 #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
727 defined(PNG_READ_BACKGROUND_SUPPORTED)
728 /* The tRNS chunk supplies transparency data for paletted images and
729 * other image types that don't need a full alpha channel. There are
730 * "num_trans" transparency values for a paletted image, stored in the
731 * same order as the palette colors, starting from index 0. Values
732 * for the data are in the range [0, 255], ranging from fully transparent
733 * to fully opaque, respectively. For non-paletted images, there is a
734 * single color specified that should be treated as fully transparent.
735 * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
737 png_bytep trans; /* transparent values for paletted image */
738 png_color_16 trans_values; /* transparent color for non-palette image */
741 #if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
742 /* The bKGD chunk gives the suggested image background color if the
743 * display program does not have its own background color and the image
744 * is needs to composited onto a background before display. The colors
745 * in "background" are normally in the same color space/depth as the
746 * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
748 png_color_16 background;
751 #if defined(PNG_oFFs_SUPPORTED)
752 /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
753 * and downwards from the top-left corner of the display, page, or other
754 * application-specific co-ordinate space. See the PNG_OFFSET_ defines
755 * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
757 png_int_32 x_offset; /* x offset on page */
758 png_int_32 y_offset; /* y offset on page */
759 png_byte offset_unit_type; /* offset units type */
762 #if defined(PNG_pHYs_SUPPORTED)
763 /* The pHYs chunk gives the physical pixel density of the image for
764 * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
765 * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
767 png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
768 png_uint_32 y_pixels_per_unit; /* vertical pixel density */
769 png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
772 #if defined(PNG_hIST_SUPPORTED)
773 /* The hIST chunk contains the relative frequency or importance of the
774 * various palette entries, so that a viewer can intelligently select a
775 * reduced-color palette, if required. Data is an array of "num_palette"
776 * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
782 #ifdef PNG_cHRM_SUPPORTED
783 /* The cHRM chunk describes the CIE color characteristics of the monitor
784 * on which the PNG was created. This data allows the viewer to do gamut
785 * mapping of the input image to ensure that the viewer sees the same
786 * colors in the image as the creator. Values are in the range
787 * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
789 #ifdef PNG_FLOATING_POINT_SUPPORTED
801 #if defined(PNG_pCAL_SUPPORTED)
802 /* The pCAL chunk describes a transformation between the stored pixel
803 * values and original physical data values used to create the image.
804 * The integer range [0, 2^bit_depth - 1] maps to the floating-point
805 * range given by [pcal_X0, pcal_X1], and are further transformed by a
806 * (possibly non-linear) transformation function given by "pcal_type"
807 * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
808 * defines below, and the PNG-Group's PNG extensions document for a
809 * complete description of the transformations and how they should be
810 * implemented, and for a description of the ASCII parameter strings.
811 * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
813 png_charp pcal_purpose; /* pCAL chunk description string */
814 png_int_32 pcal_X0; /* minimum value */
815 png_int_32 pcal_X1; /* maximum value */
816 png_charp pcal_units; /* Latin-1 string giving physical units */
817 png_charpp pcal_params; /* ASCII strings containing parameter values */
818 png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
819 png_byte pcal_nparams; /* number of parameters given in pcal_params */
822 /* New members added in libpng-1.0.6 */
823 #ifdef PNG_FREE_ME_SUPPORTED
824 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
827 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
828 /* storage for unknown chunks that the library doesn't recognize. */
829 png_unknown_chunkp unknown_chunks;
830 png_size_t unknown_chunks_num;
833 #if defined(PNG_iCCP_SUPPORTED)
834 /* iCCP chunk data. */
835 png_charp iccp_name; /* profile name */
836 png_charp iccp_profile; /* International Color Consortium profile data */
837 /* Note to maintainer: should be png_bytep */
838 png_uint_32 iccp_proflen; /* ICC profile data length */
839 png_byte iccp_compression; /* Always zero */
842 #if defined(PNG_sPLT_SUPPORTED)
843 /* data on sPLT chunks (there may be more than one). */
844 png_sPLT_tp splt_palettes;
845 png_uint_32 splt_palettes_num;
848 #if defined(PNG_sCAL_SUPPORTED)
849 /* The sCAL chunk describes the actual physical dimensions of the
850 * subject matter of the graphic. The chunk contains a unit specification
851 * a byte value, and two ASCII strings representing floating-point
852 * values. The values are width and height corresponsing to one pixel
853 * in the image. This external representation is converted to double
854 * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
856 png_byte scal_unit; /* unit of physical scale */
857 #ifdef PNG_FLOATING_POINT_SUPPORTED
858 double scal_pixel_width; /* width of one pixel */
859 double scal_pixel_height; /* height of one pixel */
861 #ifdef PNG_FIXED_POINT_SUPPORTED
862 png_charp scal_s_width; /* string containing height */
863 png_charp scal_s_height; /* string containing width */
867 #if defined(PNG_INFO_IMAGE_SUPPORTED)
868 /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
869 /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
870 png_bytepp row_pointers; /* the image bits */
873 #if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
874 png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
877 #if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
878 png_fixed_point int_x_white;
879 png_fixed_point int_y_white;
880 png_fixed_point int_x_red;
881 png_fixed_point int_y_red;
882 png_fixed_point int_x_green;
883 png_fixed_point int_y_green;
884 png_fixed_point int_x_blue;
885 png_fixed_point int_y_blue;
890 typedef png_info FAR * png_infop;
891 typedef png_info FAR * FAR * png_infopp;
893 /* Maximum positive integer used in PNG is (2^31)-1 */
894 #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
895 #define PNG_UINT_32_MAX ((png_uint_32)(-1))
896 #define PNG_SIZE_MAX ((png_size_t)(-1))
897 /* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
898 #define PNG_MAX_UINT PNG_UINT_31_MAX
900 /* These describe the color_type field in png_info. */
901 /* color type masks */
902 #define PNG_COLOR_MASK_PALETTE 1
903 #define PNG_COLOR_MASK_COLOR 2
904 #define PNG_COLOR_MASK_ALPHA 4
906 /* color types. Note that not all combinations are legal */
907 #define PNG_COLOR_TYPE_GRAY 0
908 #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
909 #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
910 #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
911 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
913 #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
914 #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
916 /* This is for compression type. PNG 1.0-1.2 only define the single type. */
917 #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
918 #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
920 /* This is for filter type. PNG 1.0-1.2 only define the single type. */
921 #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
922 #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
923 #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
925 /* These are for the interlacing type. These values should NOT be changed. */
926 #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
927 #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
928 #define PNG_INTERLACE_LAST 2 /* Not a valid value */
930 /* These are for the oFFs chunk. These values should NOT be changed. */
931 #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
932 #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
933 #define PNG_OFFSET_LAST 2 /* Not a valid value */
935 /* These are for the pCAL chunk. These values should NOT be changed. */
936 #define PNG_EQUATION_LINEAR 0 /* Linear transformation */
937 #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
938 #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
939 #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
940 #define PNG_EQUATION_LAST 4 /* Not a valid value */
942 /* These are for the sCAL chunk. These values should NOT be changed. */
943 #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
944 #define PNG_SCALE_METER 1 /* meters per pixel */
945 #define PNG_SCALE_RADIAN 2 /* radians per pixel */
946 #define PNG_SCALE_LAST 3 /* Not a valid value */
948 /* These are for the pHYs chunk. These values should NOT be changed. */
949 #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
950 #define PNG_RESOLUTION_METER 1 /* pixels/meter */
951 #define PNG_RESOLUTION_LAST 2 /* Not a valid value */
953 /* These are for the sRGB chunk. These values should NOT be changed. */
954 #define PNG_sRGB_INTENT_PERCEPTUAL 0
955 #define PNG_sRGB_INTENT_RELATIVE 1
956 #define PNG_sRGB_INTENT_SATURATION 2
957 #define PNG_sRGB_INTENT_ABSOLUTE 3
958 #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
960 /* This is for text chunks */
961 #define PNG_KEYWORD_MAX_LENGTH 79
963 /* Maximum number of entries in PLTE/sPLT/tRNS arrays */
964 #define PNG_MAX_PALETTE_LENGTH 256
966 /* These determine if an ancillary chunk's data has been successfully read
967 * from the PNG header, or if the application has filled in the corresponding
968 * data in the info_struct to be written into the output file. The values
969 * of the PNG_INFO_<chunk> defines should NOT be changed.
971 #define PNG_INFO_gAMA 0x0001
972 #define PNG_INFO_sBIT 0x0002
973 #define PNG_INFO_cHRM 0x0004
974 #define PNG_INFO_PLTE 0x0008
975 #define PNG_INFO_tRNS 0x0010
976 #define PNG_INFO_bKGD 0x0020
977 #define PNG_INFO_hIST 0x0040
978 #define PNG_INFO_pHYs 0x0080
979 #define PNG_INFO_oFFs 0x0100
980 #define PNG_INFO_tIME 0x0200
981 #define PNG_INFO_pCAL 0x0400
982 #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
983 #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
984 #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
985 #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
986 #define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
988 /* This is used for the transformation routines, as some of them
989 * change these values for the row. It also should enable using
990 * the routines for other purposes.
992 typedef struct png_row_info_struct
994 png_uint_32 width; /* width of row */
995 png_uint_32 rowbytes; /* number of bytes in row */
996 png_byte color_type; /* color type of row */
997 png_byte bit_depth; /* bit depth of row */
998 png_byte channels; /* number of channels (1, 2, 3, or 4) */
999 png_byte pixel_depth; /* bits per pixel (depth * channels) */
1002 typedef png_row_info FAR * png_row_infop;
1003 typedef png_row_info FAR * FAR * png_row_infopp;
1005 /* These are the function types for the I/O functions and for the functions
1006 * that allow the user to override the default I/O functions with his or her
1007 * own. The png_error_ptr type should match that of user-supplied warning
1008 * and error functions, while the png_rw_ptr type should match that of the
1009 * user read/write data functions.
1011 typedef struct png_struct_def png_struct;
1012 typedef png_struct FAR * png_structp;
1014 typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
1015 typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
1016 typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
1017 typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
1019 typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
1022 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1023 typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
1024 typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
1025 typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
1029 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1030 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1031 defined(PNG_LEGACY_SUPPORTED)
1032 typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
1033 png_row_infop, png_bytep));
1036 #if defined(PNG_USER_CHUNKS_SUPPORTED)
1037 typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
1039 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1040 typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
1043 /* Transform masks for the high-level interface */
1044 #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
1045 #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
1046 #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
1047 #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
1048 #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
1049 #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
1050 #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
1051 #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
1052 #define PNG_TRANSFORM_BGR 0x0080 /* read and write */
1053 #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
1054 #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
1055 #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
1056 #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */
1058 /* Flags for MNG supported features */
1059 #define PNG_FLAG_MNG_EMPTY_PLTE 0x01
1060 #define PNG_FLAG_MNG_FILTER_64 0x04
1061 #define PNG_ALL_MNG_FEATURES 0x05
1063 typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
1064 typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
1066 /* The structure that holds the information to read and write PNG files.
1067 * The only people who need to care about what is inside of this are the
1068 * people who will be modifying the library for their own special needs.
1069 * It should NOT be accessed directly by an application, except to store
1073 struct png_struct_def
1075 #ifdef PNG_SETJMP_SUPPORTED
1076 jmp_buf jmpbuf; /* used in png_error */
1078 png_error_ptr error_fn; /* function for printing errors and aborting */
1079 png_error_ptr warning_fn; /* function for printing warnings */
1080 png_voidp error_ptr; /* user supplied struct for error functions */
1081 png_rw_ptr write_data_fn; /* function for writing output data */
1082 png_rw_ptr read_data_fn; /* function for reading input data */
1083 png_voidp io_ptr; /* ptr to application struct for I/O functions */
1085 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
1086 png_user_transform_ptr read_user_transform_fn; /* user read transform */
1089 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1090 png_user_transform_ptr write_user_transform_fn; /* user write transform */
1093 /* These were added in libpng-1.0.2 */
1094 #if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
1095 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1096 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1097 png_voidp user_transform_ptr; /* user supplied struct for user transform */
1098 png_byte user_transform_depth; /* bit depth of user transformed pixels */
1099 png_byte user_transform_channels; /* channels in user transformed pixels */
1103 png_uint_32 mode; /* tells us where we are in the PNG file */
1104 png_uint_32 flags; /* flags indicating various things to libpng */
1105 png_uint_32 transformations; /* which transformations to perform */
1107 z_stream zstream; /* pointer to decompression structure (below) */
1108 png_bytep zbuf; /* buffer for zlib */
1109 png_size_t zbuf_size; /* size of zbuf */
1110 int zlib_level; /* holds zlib compression level */
1111 int zlib_method; /* holds zlib compression method */
1112 int zlib_window_bits; /* holds zlib compression window bits */
1113 int zlib_mem_level; /* holds zlib compression memory level */
1114 int zlib_strategy; /* holds zlib compression strategy */
1116 png_uint_32 width; /* width of image in pixels */
1117 png_uint_32 height; /* height of image in pixels */
1118 png_uint_32 num_rows; /* number of rows in current pass */
1119 png_uint_32 usr_width; /* width of row at start of write */
1120 png_uint_32 rowbytes; /* size of row in bytes */
1121 png_uint_32 irowbytes; /* size of current interlaced row in bytes */
1122 png_uint_32 iwidth; /* width of current interlaced row in pixels */
1123 png_uint_32 row_number; /* current row in interlace pass */
1124 png_bytep prev_row; /* buffer to save previous (unfiltered) row */
1125 png_bytep row_buf; /* buffer to save current (unfiltered) row */
1126 png_bytep sub_row; /* buffer to save "sub" row when filtering */
1127 png_bytep up_row; /* buffer to save "up" row when filtering */
1128 png_bytep avg_row; /* buffer to save "avg" row when filtering */
1129 png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
1130 png_row_info row_info; /* used for transformation routines */
1132 png_uint_32 idat_size; /* current IDAT size for read */
1133 png_uint_32 crc; /* current chunk CRC value */
1134 png_colorp palette; /* palette from the input file */
1135 png_uint_16 num_palette; /* number of color entries in palette */
1136 png_uint_16 num_trans; /* number of transparency values */
1137 png_byte chunk_name[5]; /* null-terminated name of current chunk */
1138 png_byte compression; /* file compression type (always 0) */
1139 png_byte filter; /* file filter type (always 0) */
1140 png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
1141 png_byte pass; /* current interlace pass (0 - 6) */
1142 png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
1143 png_byte color_type; /* color type of file */
1144 png_byte bit_depth; /* bit depth of file */
1145 png_byte usr_bit_depth; /* bit depth of users row */
1146 png_byte pixel_depth; /* number of bits per pixel */
1147 png_byte channels; /* number of channels in file */
1148 png_byte usr_channels; /* channels at start of write */
1149 png_byte sig_bytes; /* magic bytes read/written from start of file */
1151 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1152 #ifdef PNG_LEGACY_SUPPORTED
1153 png_byte filler; /* filler byte for pixel expansion */
1155 png_uint_16 filler; /* filler bytes for pixel expansion */
1159 #if defined(PNG_bKGD_SUPPORTED)
1160 png_byte background_gamma_type;
1161 # ifdef PNG_FLOATING_POINT_SUPPORTED
1162 float background_gamma;
1164 png_color_16 background; /* background color in screen gamma space */
1165 #if defined(PNG_READ_GAMMA_SUPPORTED)
1166 png_color_16 background_1; /* background normalized to gamma 1.0 */
1168 #endif /* PNG_bKGD_SUPPORTED */
1170 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
1171 png_flush_ptr output_flush_fn;/* Function for flushing output */
1172 png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
1173 png_uint_32 flush_rows; /* number of rows written since last flush */
1176 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1177 int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
1178 #ifdef PNG_FLOATING_POINT_SUPPORTED
1179 float gamma; /* file gamma value */
1180 float screen_gamma; /* screen gamma value (display_exponent) */
1184 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1185 png_bytep gamma_table; /* gamma table for 8-bit depth files */
1186 png_bytep gamma_from_1; /* converts from 1.0 to screen */
1187 png_bytep gamma_to_1; /* converts from file to 1.0 */
1188 png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
1189 png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
1190 png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
1193 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
1194 png_color_8 sig_bit; /* significant bits in each available channel */
1197 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1198 png_color_8 shift; /* shift for significant bit tranformation */
1201 #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
1202 || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1203 png_bytep trans; /* transparency values for paletted files */
1204 png_color_16 trans_values; /* transparency values for non-paletted files */
1207 png_read_status_ptr read_row_fn; /* called after each row is decoded */
1208 png_write_status_ptr write_row_fn; /* called after each row is encoded */
1209 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1210 png_progressive_info_ptr info_fn; /* called after header data fully read */
1211 png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
1212 png_progressive_end_ptr end_fn; /* called after image is complete */
1213 png_bytep save_buffer_ptr; /* current location in save_buffer */
1214 png_bytep save_buffer; /* buffer for previously read data */
1215 png_bytep current_buffer_ptr; /* current location in current_buffer */
1216 png_bytep current_buffer; /* buffer for recently used data */
1217 png_uint_32 push_length; /* size of current input chunk */
1218 png_uint_32 skip_length; /* bytes to skip in input data */
1219 png_size_t save_buffer_size; /* amount of data now in save_buffer */
1220 png_size_t save_buffer_max; /* total size of save_buffer */
1221 png_size_t buffer_size; /* total amount of available input data */
1222 png_size_t current_buffer_size; /* amount of data now in current_buffer */
1223 int process_mode; /* what push library is currently doing */
1224 int cur_palette; /* current push library palette index */
1226 # if defined(PNG_TEXT_SUPPORTED)
1227 png_size_t current_text_size; /* current size of text input data */
1228 png_size_t current_text_left; /* how much text left to read in input */
1229 png_charp current_text; /* current text chunk buffer */
1230 png_charp current_text_ptr; /* current location in current_text */
1231 # endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */
1233 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1235 #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
1236 /* for the Borland special 64K segment handler */
1237 png_bytepp offset_table_ptr;
1238 png_bytep offset_table;
1239 png_uint_16 offset_table_number;
1240 png_uint_16 offset_table_count;
1241 png_uint_16 offset_table_count_free;
1244 #if defined(PNG_READ_DITHER_SUPPORTED)
1245 png_bytep palette_lookup; /* lookup table for dithering */
1246 png_bytep dither_index; /* index translation for palette files */
1249 #if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
1250 png_uint_16p hist; /* histogram */
1253 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1254 png_byte heuristic_method; /* heuristic for row filter selection */
1255 png_byte num_prev_filters; /* number of weights for previous rows */
1256 png_bytep prev_filters; /* filter type(s) of previous row(s) */
1257 png_uint_16p filter_weights; /* weight(s) for previous line(s) */
1258 png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
1259 png_uint_16p filter_costs; /* relative filter calculation cost */
1260 png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
1263 #if defined(PNG_TIME_RFC1123_SUPPORTED)
1264 png_charp time_buffer; /* String to hold RFC 1123 time text */
1267 /* New members added in libpng-1.0.6 */
1269 #ifdef PNG_FREE_ME_SUPPORTED
1270 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
1273 #if defined(PNG_USER_CHUNKS_SUPPORTED)
1274 png_voidp user_chunk_ptr;
1275 png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
1278 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1280 png_bytep chunk_list;
1283 /* New members added in libpng-1.0.3 */
1284 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1285 png_byte rgb_to_gray_status;
1286 /* These were changed from png_byte in libpng-1.0.6 */
1287 png_uint_16 rgb_to_gray_red_coeff;
1288 png_uint_16 rgb_to_gray_green_coeff;
1289 png_uint_16 rgb_to_gray_blue_coeff;
1292 /* New member added in libpng-1.0.4 (renamed in 1.0.9) */
1293 #if defined(PNG_MNG_FEATURES_SUPPORTED) || \
1294 defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1295 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1296 /* changed from png_byte to png_uint_32 at version 1.2.0 */
1298 png_byte mng_features_permitted;
1300 png_uint_32 mng_features_permitted;
1301 #endif /* PNG_1_0_X */
1304 /* New member added in libpng-1.0.7 */
1305 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1306 png_fixed_point int_gamma;
1309 /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
1310 #if defined(PNG_MNG_FEATURES_SUPPORTED)
1311 png_byte filter_type;
1314 #if defined(PNG_1_0_X) || (defined(PNG_DEBUG) && defined(PNG_USE_PNGGCCRD))
1315 /* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
1316 png_uint_32 row_buf_size;
1319 /* New members added in libpng-1.2.0 */
1320 #if !defined(PNG_1_0_X) && defined(PNG_ASSEMBLER_CODE_SUPPORTED)
1321 png_byte mmx_bitdepth_threshold;
1322 png_uint_32 mmx_rowbytes_threshold;
1323 png_uint_32 asm_flags;
1326 /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
1327 #ifdef PNG_USER_MEM_SUPPORTED
1328 png_voidp mem_ptr; /* user supplied struct for mem functions */
1329 png_malloc_ptr malloc_fn; /* function for allocating memory */
1330 png_free_ptr free_fn; /* function for freeing memory */
1333 /* New member added in libpng-1.0.13 and 1.2.0 */
1334 png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
1336 #if defined(PNG_READ_DITHER_SUPPORTED)
1337 /* The following three members were added at version 1.0.14 and 1.2.4 */
1338 png_bytep dither_sort; /* working sort array */
1339 png_bytep index_to_palette; /* where the original index currently is */
1340 /* in the palette */
1341 png_bytep palette_to_index; /* which original index points to this */
1345 /* New members added in libpng-1.0.16 and 1.2.6 */
1346 png_byte compression_type;
1348 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
1349 png_uint_32 user_width_max;
1350 png_uint_32 user_height_max;
1356 /* This triggers a compiler error in png.c, if png.c and png.h
1357 * do not agree upon the version number.
1359 typedef png_structp version_1_2_8;
1361 typedef png_struct FAR * FAR * png_structpp;
1363 /* Here are the function definitions most commonly used. This is not
1364 * the place to find out how to use libpng. See libpng.txt for the
1365 * full explanation, see example.c for the summary. This just provides
1366 * a simple one line description of the use of each function.
1369 /* Returns the version number of the library */
1370 extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
1372 /* Tell lib we have already handled the first <num_bytes> magic bytes.
1373 * Handling more than 8 bytes from the beginning of the file is an error.
1375 extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
1378 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
1379 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
1380 * signature, and non-zero otherwise. Having num_to_check == 0 or
1381 * start > 7 will always fail (ie return non-zero).
1383 extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
1384 png_size_t num_to_check));
1386 /* Simple signature checking function. This is the same as calling
1387 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
1389 extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
1391 /* Allocate and initialize png_ptr struct for reading, and any other memory. */
1392 extern PNG_EXPORT(png_structp,png_create_read_struct)
1393 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1394 png_error_ptr error_fn, png_error_ptr warn_fn));
1396 /* Allocate and initialize png_ptr struct for writing, and any other memory */
1397 extern PNG_EXPORT(png_structp,png_create_write_struct)
1398 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1399 png_error_ptr error_fn, png_error_ptr warn_fn));
1401 #ifdef PNG_WRITE_SUPPORTED
1402 extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
1403 PNGARG((png_structp png_ptr));
1406 #ifdef PNG_WRITE_SUPPORTED
1407 extern PNG_EXPORT(void,png_set_compression_buffer_size)
1408 PNGARG((png_structp png_ptr, png_uint_32 size));
1411 /* Reset the compression stream */
1412 extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
1414 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
1415 #ifdef PNG_USER_MEM_SUPPORTED
1416 extern PNG_EXPORT(png_structp,png_create_read_struct_2)
1417 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1418 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1419 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1420 extern PNG_EXPORT(png_structp,png_create_write_struct_2)
1421 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1422 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1423 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1426 /* Write a PNG chunk - size, type, (optional) data, CRC. */
1427 extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
1428 png_bytep chunk_name, png_bytep data, png_size_t length));
1430 /* Write the start of a PNG chunk - length and chunk name. */
1431 extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
1432 png_bytep chunk_name, png_uint_32 length));
1434 /* Write the data of a PNG chunk started with png_write_chunk_start(). */
1435 extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
1436 png_bytep data, png_size_t length));
1438 /* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1439 extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
1441 /* Allocate and initialize the info structure */
1442 extern PNG_EXPORT(png_infop,png_create_info_struct)
1443 PNGARG((png_structp png_ptr));
1445 /* Initialize the info structure (old interface - DEPRECATED) */
1446 extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
1447 #undef png_info_init
1448 #define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
1449 png_sizeof(png_info));
1450 extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
1451 png_size_t png_info_struct_size));
1453 /* Writes all the PNG information before the image. */
1454 extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
1455 png_infop info_ptr));
1456 extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
1457 png_infop info_ptr));
1459 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1460 /* read the information before the actual image data. */
1461 extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
1462 png_infop info_ptr));
1465 #if defined(PNG_TIME_RFC1123_SUPPORTED)
1466 extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
1467 PNGARG((png_structp png_ptr, png_timep ptime));
1470 #if !defined(_WIN32_WCE)
1471 /* "time.h" functions are not supported on WindowsCE */
1472 #if defined(PNG_WRITE_tIME_SUPPORTED)
1473 /* convert from a struct tm to png_time */
1474 extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
1475 struct tm FAR * ttime));
1477 /* convert from time_t to png_time. Uses gmtime() */
1478 extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
1480 #endif /* PNG_WRITE_tIME_SUPPORTED */
1481 #endif /* _WIN32_WCE */
1483 #if defined(PNG_READ_EXPAND_SUPPORTED)
1484 /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1485 extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
1486 extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
1487 extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
1488 extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
1491 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1492 /* Use blue, green, red order for pixels. */
1493 extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
1496 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
1497 /* Expand the grayscale to 24-bit RGB if necessary. */
1498 extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
1501 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1502 /* Reduce RGB to grayscale. */
1503 #ifdef PNG_FLOATING_POINT_SUPPORTED
1504 extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
1505 int error_action, double red, double green ));
1507 extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
1508 int error_action, png_fixed_point red, png_fixed_point green ));
1509 extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
1513 extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
1514 png_colorp palette));
1516 #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1517 extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
1520 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1521 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1522 extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
1525 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1526 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1527 extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
1530 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1531 /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
1532 extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
1533 png_uint_32 filler, int flags));
1534 /* The values of the PNG_FILLER_ defines should NOT be changed */
1535 #define PNG_FILLER_BEFORE 0
1536 #define PNG_FILLER_AFTER 1
1537 /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
1538 #if !defined(PNG_1_0_X)
1539 extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
1540 png_uint_32 filler, int flags));
1542 #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
1544 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1545 /* Swap bytes in 16-bit depth files. */
1546 extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
1549 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1550 /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1551 extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
1554 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1555 /* Swap packing order of pixels in bytes. */
1556 extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
1559 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1560 /* Converts files to legal bit depths. */
1561 extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
1562 png_color_8p true_bits));
1565 #if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1566 defined(PNG_WRITE_INTERLACING_SUPPORTED)
1567 /* Have the code handle the interlacing. Returns the number of passes. */
1568 extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
1571 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1572 /* Invert monochrome files */
1573 extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
1576 #if defined(PNG_READ_BACKGROUND_SUPPORTED)
1577 /* Handle alpha and tRNS by replacing with a background color. */
1578 #ifdef PNG_FLOATING_POINT_SUPPORTED
1579 extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
1580 png_color_16p background_color, int background_gamma_code,
1581 int need_expand, double background_gamma));
1583 #define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1584 #define PNG_BACKGROUND_GAMMA_SCREEN 1
1585 #define PNG_BACKGROUND_GAMMA_FILE 2
1586 #define PNG_BACKGROUND_GAMMA_UNIQUE 3
1589 #if defined(PNG_READ_16_TO_8_SUPPORTED)
1590 /* strip the second byte of information from a 16-bit depth file. */
1591 extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
1594 #if defined(PNG_READ_DITHER_SUPPORTED)
1595 /* Turn on dithering, and reduce the palette to the number of colors available. */
1596 extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
1597 png_colorp palette, int num_palette, int maximum_colors,
1598 png_uint_16p histogram, int full_dither));
1601 #if defined(PNG_READ_GAMMA_SUPPORTED)
1602 /* Handle gamma correction. Screen_gamma=(display_exponent) */
1603 #ifdef PNG_FLOATING_POINT_SUPPORTED
1604 extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
1605 double screen_gamma, double default_file_gamma));
1609 #if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1610 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1611 /* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
1612 /* Deprecated and will be removed. Use png_permit_mng_features() instead. */
1613 extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
1614 int empty_plte_permitted));
1617 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
1618 /* Set how many lines between output flushes - 0 for no flushing */
1619 extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
1620 /* Flush the current PNG output buffer */
1621 extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
1624 /* optional update palette with requested transformations */
1625 extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
1627 /* optional call to update the users info structure */
1628 extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
1629 png_infop info_ptr));
1631 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1632 /* read one or more rows of image data. */
1633 extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
1634 png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
1637 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1638 /* read a row of data. */
1639 extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
1641 png_bytep display_row));
1644 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1645 /* read the whole image into memory at once. */
1646 extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
1650 /* write a row of image data */
1651 extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
1654 /* write a few rows of image data */
1655 extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
1656 png_bytepp row, png_uint_32 num_rows));
1658 /* write the image data */
1659 extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
1662 /* writes the end of the PNG file. */
1663 extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
1664 png_infop info_ptr));
1666 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1667 /* read the end of the PNG file. */
1668 extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
1669 png_infop info_ptr));
1672 /* free any memory associated with the png_info_struct */
1673 extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
1674 png_infopp info_ptr_ptr));
1676 /* free any memory associated with the png_struct and the png_info_structs */
1677 extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
1678 png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1680 /* free all memory used by the read (old method - NOT DLL EXPORTED) */
1681 extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
1682 png_infop end_info_ptr));
1684 /* free any memory associated with the png_struct and the png_info_structs */
1685 extern PNG_EXPORT(void,png_destroy_write_struct)
1686 PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
1688 /* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1689 extern void png_write_destroy PNGARG((png_structp png_ptr));
1691 /* set the libpng method of handling chunk CRC errors */
1692 extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
1693 int crit_action, int ancil_action));
1695 /* Values for png_set_crc_action() to say how to handle CRC errors in
1696 * ancillary and critical chunks, and whether to use the data contained
1697 * therein. Note that it is impossible to "discard" data in a critical
1698 * chunk. For versions prior to 0.90, the action was always error/quit,
1699 * whereas in version 0.90 and later, the action for CRC errors in ancillary
1700 * chunks is warn/discard. These values should NOT be changed.
1702 * value action:critical action:ancillary
1704 #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1705 #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1706 #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1707 #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1708 #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1709 #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1711 /* These functions give the user control over the scan-line filtering in
1712 * libpng and the compression methods used by zlib. These functions are
1713 * mainly useful for testing, as the defaults should work with most users.
1714 * Those users who are tight on memory or want faster performance at the
1715 * expense of compression can modify them. See the compression library
1716 * header file (zlib.h) for an explination of the compression functions.
1719 /* set the filtering method(s) used by libpng. Currently, the only valid
1720 * value for "method" is 0.
1722 extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
1725 /* Flags for png_set_filter() to say which filters to use. The flags
1726 * are chosen so that they don't conflict with real filter types
1727 * below, in case they are supplied instead of the #defined constants.
1728 * These values should NOT be changed.
1730 #define PNG_NO_FILTERS 0x00
1731 #define PNG_FILTER_NONE 0x08
1732 #define PNG_FILTER_SUB 0x10
1733 #define PNG_FILTER_UP 0x20
1734 #define PNG_FILTER_AVG 0x40
1735 #define PNG_FILTER_PAETH 0x80
1736 #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
1737 PNG_FILTER_AVG | PNG_FILTER_PAETH)
1739 /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1740 * These defines should NOT be changed.
1742 #define PNG_FILTER_VALUE_NONE 0
1743 #define PNG_FILTER_VALUE_SUB 1
1744 #define PNG_FILTER_VALUE_UP 2
1745 #define PNG_FILTER_VALUE_AVG 3
1746 #define PNG_FILTER_VALUE_PAETH 4
1747 #define PNG_FILTER_VALUE_LAST 5
1749 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
1750 /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
1751 * defines, either the default (minimum-sum-of-absolute-differences), or
1752 * the experimental method (weighted-minimum-sum-of-absolute-differences).
1754 * Weights are factors >= 1.0, indicating how important it is to keep the
1755 * filter type consistent between rows. Larger numbers mean the current
1756 * filter is that many times as likely to be the same as the "num_weights"
1757 * previous filters. This is cumulative for each previous row with a weight.
1758 * There needs to be "num_weights" values in "filter_weights", or it can be
1759 * NULL if the weights aren't being specified. Weights have no influence on
1760 * the selection of the first row filter. Well chosen weights can (in theory)
1761 * improve the compression for a given image.
1763 * Costs are factors >= 1.0 indicating the relative decoding costs of a
1764 * filter type. Higher costs indicate more decoding expense, and are
1765 * therefore less likely to be selected over a filter with lower computational
1766 * costs. There needs to be a value in "filter_costs" for each valid filter
1767 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
1768 * setting the costs. Costs try to improve the speed of decompression without
1769 * unduly increasing the compressed image size.
1771 * A negative weight or cost indicates the default value is to be used, and
1772 * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
1773 * The default values for both weights and costs are currently 1.0, but may
1774 * change if good general weighting/cost heuristics can be found. If both
1775 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
1776 * to the UNWEIGHTED method, but with added encoding time/computation.
1778 #ifdef PNG_FLOATING_POINT_SUPPORTED
1779 extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
1780 int heuristic_method, int num_weights, png_doublep filter_weights,
1781 png_doublep filter_costs));
1783 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1785 /* Heuristic used for row filter selection. These defines should NOT be
1788 #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1789 #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1790 #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1791 #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1793 /* Set the library compression level. Currently, valid values range from
1794 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1795 * (0 - no compression, 9 - "maximal" compression). Note that tests have
1796 * shown that zlib compression levels 3-6 usually perform as well as level 9
1797 * for PNG images, and do considerably fewer caclulations. In the future,
1798 * these values may not correspond directly to the zlib compression levels.
1800 extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
1803 extern PNG_EXPORT(void,png_set_compression_mem_level)
1804 PNGARG((png_structp png_ptr, int mem_level));
1806 extern PNG_EXPORT(void,png_set_compression_strategy)
1807 PNGARG((png_structp png_ptr, int strategy));
1809 extern PNG_EXPORT(void,png_set_compression_window_bits)
1810 PNGARG((png_structp png_ptr, int window_bits));
1812 extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
1815 /* These next functions are called for input/output, memory, and error
1816 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1817 * and call standard C I/O routines such as fread(), fwrite(), and
1818 * fprintf(). These functions can be made to use other I/O routines
1819 * at run time for those applications that need to handle I/O in a
1820 * different manner by calling png_set_???_fn(). See libpng.txt for
1824 #if !defined(PNG_NO_STDIO)
1825 /* Initialize the input/output for the PNG file to the default functions. */
1826 extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
1829 /* Replace the (error and abort), and warning functions with user
1830 * supplied functions. If no messages are to be printed you must still
1831 * write and use replacement functions. The replacement error_fn should
1832 * still do a longjmp to the last setjmp location if you are using this
1833 * method of error handling. If error_fn or warning_fn is NULL, the
1834 * default function will be used.
1837 extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
1838 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1840 /* Return the user pointer associated with the error functions */
1841 extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
1843 /* Replace the default data output functions with a user supplied one(s).
1844 * If buffered output is not used, then output_flush_fn can be set to NULL.
1845 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1846 * output_flush_fn will be ignored (and thus can be NULL).
1848 extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
1849 png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1851 /* Replace the default data input function with a user supplied one. */
1852 extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
1853 png_voidp io_ptr, png_rw_ptr read_data_fn));
1855 /* Return the user pointer associated with the I/O functions */
1856 extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
1858 extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
1859 png_read_status_ptr read_row_fn));
1861 extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
1862 png_write_status_ptr write_row_fn));
1864 #ifdef PNG_USER_MEM_SUPPORTED
1865 /* Replace the default memory allocation functions with user supplied one(s). */
1866 extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
1867 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1868 /* Return the user pointer associated with the memory functions */
1869 extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
1872 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1873 defined(PNG_LEGACY_SUPPORTED)
1874 extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
1875 png_ptr, png_user_transform_ptr read_user_transform_fn));
1878 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1879 defined(PNG_LEGACY_SUPPORTED)
1880 extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
1881 png_ptr, png_user_transform_ptr write_user_transform_fn));
1884 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1885 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1886 defined(PNG_LEGACY_SUPPORTED)
1887 extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
1888 png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
1889 int user_transform_channels));
1890 /* Return the user pointer associated with the user transform functions */
1891 extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
1892 PNGARG((png_structp png_ptr));
1895 #ifdef PNG_USER_CHUNKS_SUPPORTED
1896 extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
1897 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
1898 extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
1902 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1903 /* Sets the function callbacks for the push reader, and a pointer to a
1904 * user-defined structure available to the callback functions.
1906 extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
1907 png_voidp progressive_ptr,
1908 png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
1909 png_progressive_end_ptr end_fn));
1911 /* returns the user pointer associated with the push read functions */
1912 extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
1913 PNGARG((png_structp png_ptr));
1915 /* function to be called when data becomes available */
1916 extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
1917 png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
1919 /* function that combines rows. Not very much different than the
1920 * png_combine_row() call. Is this even used?????
1922 extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
1923 png_bytep old_row, png_bytep new_row));
1924 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1926 extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
1929 #if defined(PNG_1_0_X)
1930 # define png_malloc_warn png_malloc
1932 /* Added at libpng version 1.2.4 */
1933 extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
1937 /* frees a pointer allocated by png_malloc() */
1938 extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
1940 #if defined(PNG_1_0_X)
1941 /* Function to allocate memory for zlib. */
1942 extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
1945 /* Function to free memory for zlib */
1946 extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
1949 /* Free data that was allocated internally */
1950 extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
1951 png_infop info_ptr, png_uint_32 free_me, int num));
1952 #ifdef PNG_FREE_ME_SUPPORTED
1953 /* Reassign responsibility for freeing existing data, whether allocated
1954 * by libpng or by the application */
1955 extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
1956 png_infop info_ptr, int freer, png_uint_32 mask));
1958 /* assignments for png_data_freer */
1959 #define PNG_DESTROY_WILL_FREE_DATA 1
1960 #define PNG_SET_WILL_FREE_DATA 1
1961 #define PNG_USER_WILL_FREE_DATA 2
1962 /* Flags for png_ptr->free_me and info_ptr->free_me */
1963 #define PNG_FREE_HIST 0x0008
1964 #define PNG_FREE_ICCP 0x0010
1965 #define PNG_FREE_SPLT 0x0020
1966 #define PNG_FREE_ROWS 0x0040
1967 #define PNG_FREE_PCAL 0x0080
1968 #define PNG_FREE_SCAL 0x0100
1969 #define PNG_FREE_UNKN 0x0200
1970 #define PNG_FREE_LIST 0x0400
1971 #define PNG_FREE_PLTE 0x1000
1972 #define PNG_FREE_TRNS 0x2000
1973 #define PNG_FREE_TEXT 0x4000
1974 #define PNG_FREE_ALL 0x7fff
1975 #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
1977 #ifdef PNG_USER_MEM_SUPPORTED
1978 extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
1980 extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
1984 extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
1985 png_voidp s1, png_voidp s2, png_uint_32 size));
1987 extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
1988 png_voidp s1, int value, png_uint_32 size));
1990 #if defined(USE_FAR_KEYWORD) /* memory model conversion function */
1991 extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
1993 #endif /* USE_FAR_KEYWORD */
1995 /* Fatal error in PNG image of libpng - can't continue */
1996 extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
1997 png_const_charp error_message));
1999 /* The same, but the chunk name is prepended to the error string. */
2000 extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
2001 png_const_charp error_message));
2003 /* Non-fatal error in libpng. Can continue, but may have a problem. */
2004 extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
2005 png_const_charp warning_message));
2007 /* Non-fatal error in libpng, chunk name is prepended to message. */
2008 extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
2009 png_const_charp warning_message));
2011 /* The png_set_<chunk> functions are for storing values in the png_info_struct.
2012 * Similarly, the png_get_<chunk> calls are used to read values from the
2013 * png_info_struct, either storing the parameters in the passed variables, or
2014 * setting pointers into the png_info_struct where the data is stored. The
2015 * png_get_<chunk> functions return a non-zero value if the data was available
2016 * in info_ptr, or return zero and do not change any of the parameters if the
2017 * data was not available.
2019 * These functions should be used instead of directly accessing png_info
2020 * to avoid problems with future changes in the size and internal layout of
2023 /* Returns "flag" if chunk data is valid in info_ptr. */
2024 extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
2025 png_infop info_ptr, png_uint_32 flag));
2027 /* Returns number of bytes needed to hold a transformed row. */
2028 extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
2029 png_infop info_ptr));
2031 #if defined(PNG_INFO_IMAGE_SUPPORTED)
2032 /* Returns row_pointers, which is an array of pointers to scanlines that was
2033 returned from png_read_png(). */
2034 extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
2035 png_infop info_ptr));
2036 /* Set row_pointers, which is an array of pointers to scanlines for use
2037 by png_write_png(). */
2038 extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
2039 png_infop info_ptr, png_bytepp row_pointers));
2042 /* Returns number of color channels in image. */
2043 extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
2044 png_infop info_ptr));
2046 #ifdef PNG_EASY_ACCESS_SUPPORTED
2047 /* Returns image width in pixels. */
2048 extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
2049 png_ptr, png_infop info_ptr));
2051 /* Returns image height in pixels. */
2052 extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
2053 png_ptr, png_infop info_ptr));
2055 /* Returns image bit_depth. */
2056 extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
2057 png_ptr, png_infop info_ptr));
2059 /* Returns image color_type. */
2060 extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
2061 png_ptr, png_infop info_ptr));
2063 /* Returns image filter_type. */
2064 extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
2065 png_ptr, png_infop info_ptr));
2067 /* Returns image interlace_type. */
2068 extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
2069 png_ptr, png_infop info_ptr));
2071 /* Returns image compression_type. */
2072 extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
2073 png_ptr, png_infop info_ptr));
2075 /* Returns image resolution in pixels per meter, from pHYs chunk data. */
2076 extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
2077 png_ptr, png_infop info_ptr));
2078 extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
2079 png_ptr, png_infop info_ptr));
2080 extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
2081 png_ptr, png_infop info_ptr));
2083 /* Returns pixel aspect ratio, computed from pHYs chunk data. */
2084 #ifdef PNG_FLOATING_POINT_SUPPORTED
2085 extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
2086 png_ptr, png_infop info_ptr));
2089 /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
2090 extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
2091 png_ptr, png_infop info_ptr));
2092 extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
2093 png_ptr, png_infop info_ptr));
2094 extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
2095 png_ptr, png_infop info_ptr));
2096 extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
2097 png_ptr, png_infop info_ptr));
2099 #endif /* PNG_EASY_ACCESS_SUPPORTED */
2101 /* Returns pointer to signature string read from PNG header */
2102 extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
2103 png_infop info_ptr));
2105 #if defined(PNG_bKGD_SUPPORTED)
2106 extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
2107 png_infop info_ptr, png_color_16p *background));
2110 #if defined(PNG_bKGD_SUPPORTED)
2111 extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
2112 png_infop info_ptr, png_color_16p background));
2115 #if defined(PNG_cHRM_SUPPORTED)
2116 #ifdef PNG_FLOATING_POINT_SUPPORTED
2117 extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
2118 png_infop info_ptr, double *white_x, double *white_y, double *red_x,
2119 double *red_y, double *green_x, double *green_y, double *blue_x,
2122 #ifdef PNG_FIXED_POINT_SUPPORTED
2123 extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
2124 png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
2125 *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
2126 png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
2127 *int_blue_x, png_fixed_point *int_blue_y));
2131 #if defined(PNG_cHRM_SUPPORTED)
2132 #ifdef PNG_FLOATING_POINT_SUPPORTED
2133 extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
2134 png_infop info_ptr, double white_x, double white_y, double red_x,
2135 double red_y, double green_x, double green_y, double blue_x, double blue_y));
2137 #ifdef PNG_FIXED_POINT_SUPPORTED
2138 extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
2139 png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
2140 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2141 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2142 png_fixed_point int_blue_y));
2146 #if defined(PNG_gAMA_SUPPORTED)
2147 #ifdef PNG_FLOATING_POINT_SUPPORTED
2148 extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
2149 png_infop info_ptr, double *file_gamma));
2151 extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
2152 png_infop info_ptr, png_fixed_point *int_file_gamma));
2155 #if defined(PNG_gAMA_SUPPORTED)
2156 #ifdef PNG_FLOATING_POINT_SUPPORTED
2157 extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
2158 png_infop info_ptr, double file_gamma));
2160 extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
2161 png_infop info_ptr, png_fixed_point int_file_gamma));
2164 #if defined(PNG_hIST_SUPPORTED)
2165 extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
2166 png_infop info_ptr, png_uint_16p *hist));
2169 #if defined(PNG_hIST_SUPPORTED)
2170 extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
2171 png_infop info_ptr, png_uint_16p hist));
2174 extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
2175 png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
2176 int *bit_depth, int *color_type, int *interlace_method,
2177 int *compression_method, int *filter_method));
2179 extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
2180 png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
2181 int color_type, int interlace_method, int compression_method,
2182 int filter_method));
2184 #if defined(PNG_oFFs_SUPPORTED)
2185 extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
2186 png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
2190 #if defined(PNG_oFFs_SUPPORTED)
2191 extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
2192 png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
2196 #if defined(PNG_pCAL_SUPPORTED)
2197 extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
2198 png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
2199 int *type, int *nparams, png_charp *units, png_charpp *params));
2202 #if defined(PNG_pCAL_SUPPORTED)
2203 extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
2204 png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
2205 int type, int nparams, png_charp units, png_charpp params));
2208 #if defined(PNG_pHYs_SUPPORTED)
2209 extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
2210 png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
2213 #if defined(PNG_pHYs_SUPPORTED)
2214 extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
2215 png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
2218 extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
2219 png_infop info_ptr, png_colorp *palette, int *num_palette));
2221 extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
2222 png_infop info_ptr, png_colorp palette, int num_palette));
2224 #if defined(PNG_sBIT_SUPPORTED)
2225 extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
2226 png_infop info_ptr, png_color_8p *sig_bit));
2229 #if defined(PNG_sBIT_SUPPORTED)
2230 extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
2231 png_infop info_ptr, png_color_8p sig_bit));
2234 #if defined(PNG_sRGB_SUPPORTED)
2235 extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
2236 png_infop info_ptr, int *intent));
2239 #if defined(PNG_sRGB_SUPPORTED)
2240 extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
2241 png_infop info_ptr, int intent));
2242 extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
2243 png_infop info_ptr, int intent));
2246 #if defined(PNG_iCCP_SUPPORTED)
2247 extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
2248 png_infop info_ptr, png_charpp name, int *compression_type,
2249 png_charpp profile, png_uint_32 *proflen));
2250 /* Note to maintainer: profile should be png_bytepp */
2253 #if defined(PNG_iCCP_SUPPORTED)
2254 extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
2255 png_infop info_ptr, png_charp name, int compression_type,
2256 png_charp profile, png_uint_32 proflen));
2257 /* Note to maintainer: profile should be png_bytep */
2260 #if defined(PNG_sPLT_SUPPORTED)
2261 extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
2262 png_infop info_ptr, png_sPLT_tpp entries));
2265 #if defined(PNG_sPLT_SUPPORTED)
2266 extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
2267 png_infop info_ptr, png_sPLT_tp entries, int nentries));
2270 #if defined(PNG_TEXT_SUPPORTED)
2271 /* png_get_text also returns the number of text chunks in *num_text */
2272 extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
2273 png_infop info_ptr, png_textp *text_ptr, int *num_text));
2277 * Note while png_set_text() will accept a structure whose text,
2278 * language, and translated keywords are NULL pointers, the structure
2279 * returned by png_get_text will always contain regular
2280 * zero-terminated C strings. They might be empty strings but
2281 * they will never be NULL pointers.
2284 #if defined(PNG_TEXT_SUPPORTED)
2285 extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
2286 png_infop info_ptr, png_textp text_ptr, int num_text));
2289 #if defined(PNG_tIME_SUPPORTED)
2290 extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
2291 png_infop info_ptr, png_timep *mod_time));
2294 #if defined(PNG_tIME_SUPPORTED)
2295 extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
2296 png_infop info_ptr, png_timep mod_time));
2299 #if defined(PNG_tRNS_SUPPORTED)
2300 extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
2301 png_infop info_ptr, png_bytep *trans, int *num_trans,
2302 png_color_16p *trans_values));
2305 #if defined(PNG_tRNS_SUPPORTED)
2306 extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
2307 png_infop info_ptr, png_bytep trans, int num_trans,
2308 png_color_16p trans_values));
2311 #if defined(PNG_tRNS_SUPPORTED)
2314 #if defined(PNG_sCAL_SUPPORTED)
2315 #ifdef PNG_FLOATING_POINT_SUPPORTED
2316 extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
2317 png_infop info_ptr, int *unit, double *width, double *height));
2319 #ifdef PNG_FIXED_POINT_SUPPORTED
2320 extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
2321 png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
2324 #endif /* PNG_sCAL_SUPPORTED */
2326 #if defined(PNG_sCAL_SUPPORTED)
2327 #ifdef PNG_FLOATING_POINT_SUPPORTED
2328 extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
2329 png_infop info_ptr, int unit, double width, double height));
2331 #ifdef PNG_FIXED_POINT_SUPPORTED
2332 extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
2333 png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
2335 #endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
2337 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
2338 /* provide a list of chunks and how they are to be handled, if the built-in
2339 handling or default unknown chunk handling is not desired. Any chunks not
2340 listed will be handled in the default manner. The IHDR and IEND chunks
2342 keep = 0: follow default behavour
2344 = 2: keep only if safe-to-copy
2345 = 3: keep even if unsafe-to-copy
2347 extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
2348 png_ptr, int keep, png_bytep chunk_list, int num_chunks));
2349 extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
2350 png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
2351 extern PNG_EXPORT(void, png_set_unknown_chunk_location)
2352 PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
2353 extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
2354 png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
2356 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2357 PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
2361 /* Png_free_data() will turn off the "valid" flag for anything it frees.
2362 If you need to turn it off for a chunk that your application has freed,
2363 you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
2364 extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
2365 png_infop info_ptr, int mask));
2367 #if defined(PNG_INFO_IMAGE_SUPPORTED)
2368 /* The "params" pointer is currently not used and is for future expansion. */
2369 extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
2373 extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
2379 /* Define PNG_DEBUG at compile time for debugging information. Higher
2380 * numbers for PNG_DEBUG mean more debugging information. This has
2381 * only been added since version 0.95 so it is not implemented throughout
2382 * libpng yet, but more support will be added as needed.
2386 #if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
2389 #define png_debug(l,m) _RPT0(_CRT_WARN,m)
2390 #define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1)
2391 #define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
2393 #else /* PNG_DEBUG_FILE || !_MSC_VER */
2394 #ifndef PNG_DEBUG_FILE
2395 #define PNG_DEBUG_FILE stderr
2396 #endif /* PNG_DEBUG_FILE */
2398 #define png_debug(l,m) \
2401 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2402 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
2404 #define png_debug1(l,m,p1) \
2407 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2408 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
2410 #define png_debug2(l,m,p1,p2) \
2413 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2414 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
2416 #endif /* (PNG_DEBUG > 1) */
2417 #endif /* _MSC_VER */
2418 #endif /* (PNG_DEBUG > 0) */
2419 #endif /* PNG_DEBUG */
2421 #define png_debug(l, m)
2424 #define png_debug1(l, m, p1)
2427 #define png_debug2(l, m, p1, p2)
2430 extern PNG_EXPORT(png_bytep,png_sig_bytes) PNGARG((void));
2432 extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
2433 extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
2434 extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
2435 extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
2437 #ifdef PNG_MNG_FEATURES_SUPPORTED
2438 extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
2439 png_ptr, png_uint_32 mng_features_permitted));
2442 /* For use in png_set_keep_unknown, added to version 1.2.6 */
2443 #define PNG_HANDLE_CHUNK_AS_DEFAULT 0
2444 #define PNG_HANDLE_CHUNK_NEVER 1
2445 #define PNG_HANDLE_CHUNK_IF_SAFE 2
2446 #define PNG_HANDLE_CHUNK_ALWAYS 3
2448 /* Added to version 1.2.0 */
2449 #if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
2450 #define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
2451 #define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
2452 #define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
2453 #define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
2454 #define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
2455 #define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
2456 #define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
2457 #define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
2458 #define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
2460 #define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
2461 | PNG_ASM_FLAG_MMX_READ_INTERLACE \
2462 | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
2463 | PNG_ASM_FLAG_MMX_READ_FILTER_UP \
2464 | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
2465 | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
2466 #define PNG_MMX_WRITE_FLAGS ( 0 )
2468 #define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
2469 | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
2470 | PNG_MMX_READ_FLAGS \
2471 | PNG_MMX_WRITE_FLAGS )
2473 #define PNG_SELECT_READ 1
2474 #define PNG_SELECT_WRITE 2
2476 #if !defined(PNG_1_0_X)
2478 extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
2479 PNGARG((int flag_select, int *compilerID));
2482 extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
2483 PNGARG((int flag_select));
2486 extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
2487 PNGARG((png_structp png_ptr));
2490 extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
2491 PNGARG((png_structp png_ptr));
2494 extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
2495 PNGARG((png_structp png_ptr));
2498 extern PNG_EXPORT(void,png_set_asm_flags)
2499 PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
2502 extern PNG_EXPORT(void,png_set_mmx_thresholds)
2503 PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
2504 png_uint_32 mmx_rowbytes_threshold));
2506 #endif /* PNG_1_0_X */
2507 #endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
2509 #if !defined(PNG_1_0_X)
2510 /* png.c, pnggccrd.c, or pngvcrd.c */
2511 extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
2513 /* Strip the prepended error numbers ("#nnn ") from error and warning
2514 * messages before passing them to the error or warning handler. */
2515 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
2516 extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
2517 png_ptr, png_uint_32 strip_mode));
2520 #endif /* PNG_1_0_X */
2522 /* Added at libpng-1.2.6 */
2523 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
2524 extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
2525 png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
2526 extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
2528 extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
2532 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
2534 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2535 /* With these routines we avoid an integer divide, which will be slower on
2536 * most machines. However, it does take more operations than the corresponding
2537 * divide method, so it may be slower on a few RISC systems. There are two
2538 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2540 * Note that the rounding factors are NOT supposed to be the same! 128 and
2541 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2544 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2547 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2549 # define png_composite(composite, fg, alpha, bg) \
2550 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
2551 + (png_uint_16)(bg)*(png_uint_16)(255 - \
2552 (png_uint_16)(alpha)) + (png_uint_16)128); \
2553 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2555 # define png_composite_16(composite, fg, alpha, bg) \
2556 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
2557 + (png_uint_32)(bg)*(png_uint_32)(65535L - \
2558 (png_uint_32)(alpha)) + (png_uint_32)32768L); \
2559 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
2561 #else /* standard method using integer division */
2563 # define png_composite(composite, fg, alpha, bg) \
2564 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2565 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2566 (png_uint_16)127) / 255)
2568 # define png_composite_16(composite, fg, alpha, bg) \
2569 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2570 (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
2571 (png_uint_32)32767) / (png_uint_32)65535L)
2573 #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
2575 /* These next functions are used internally in the code. They generally
2576 * shouldn't be used unless you are writing code to add or replace some
2577 * functionality in libpng. More information about most functions can
2578 * be found in the files where the functions are located.
2581 #if defined(PNG_INTERNAL)
2583 /* Various modes of operation. Note that after an init, mode is set to
2584 * zero automatically when the structure is created.
2586 #define PNG_HAVE_IHDR 0x01
2587 #define PNG_HAVE_PLTE 0x02
2588 #define PNG_HAVE_IDAT 0x04
2589 #define PNG_AFTER_IDAT 0x08
2590 #define PNG_HAVE_IEND 0x10
2591 #define PNG_HAVE_gAMA 0x20
2592 #define PNG_HAVE_cHRM 0x40
2593 #define PNG_HAVE_sRGB 0x80
2594 #define PNG_HAVE_CHUNK_HEADER 0x100
2595 #define PNG_WROTE_tIME 0x200
2596 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
2597 #define PNG_BACKGROUND_IS_GRAY 0x800
2598 #define PNG_HAVE_PNG_SIGNATURE 0x1000
2600 /* flags for the transformations the PNG library does on the image data */
2601 #define PNG_BGR 0x0001
2602 #define PNG_INTERLACE 0x0002
2603 #define PNG_PACK 0x0004
2604 #define PNG_SHIFT 0x0008
2605 #define PNG_SWAP_BYTES 0x0010
2606 #define PNG_INVERT_MONO 0x0020
2607 #define PNG_DITHER 0x0040
2608 #define PNG_BACKGROUND 0x0080
2609 #define PNG_BACKGROUND_EXPAND 0x0100
2611 #define PNG_16_TO_8 0x0400
2612 #define PNG_RGBA 0x0800
2613 #define PNG_EXPAND 0x1000
2614 #define PNG_GAMMA 0x2000
2615 #define PNG_GRAY_TO_RGB 0x4000
2616 #define PNG_FILLER 0x8000L
2617 #define PNG_PACKSWAP 0x10000L
2618 #define PNG_SWAP_ALPHA 0x20000L
2619 #define PNG_STRIP_ALPHA 0x40000L
2620 #define PNG_INVERT_ALPHA 0x80000L
2621 #define PNG_USER_TRANSFORM 0x100000L
2622 #define PNG_RGB_TO_GRAY_ERR 0x200000L
2623 #define PNG_RGB_TO_GRAY_WARN 0x400000L
2624 #define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
2625 /* 0x800000L Unused */
2626 #define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
2627 /* 0x2000000L unused */
2628 /* 0x4000000L unused */
2629 /* 0x8000000L unused */
2630 /* 0x10000000L unused */
2631 /* 0x20000000L unused */
2632 /* 0x40000000L unused */
2634 /* flags for png_create_struct */
2635 #define PNG_STRUCT_PNG 0x0001
2636 #define PNG_STRUCT_INFO 0x0002
2638 /* Scaling factor for filter heuristic weighting calculations */
2639 #define PNG_WEIGHT_SHIFT 8
2640 #define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
2641 #define PNG_COST_SHIFT 3
2642 #define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
2644 /* flags for the png_ptr->flags rather than declaring a byte for each one */
2645 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
2646 #define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
2647 #define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
2648 #define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
2649 #define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
2650 #define PNG_FLAG_ZLIB_FINISHED 0x0020
2651 #define PNG_FLAG_ROW_INIT 0x0040
2652 #define PNG_FLAG_FILLER_AFTER 0x0080
2653 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
2654 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
2655 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400
2656 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
2657 #define PNG_FLAG_FREE_PLTE 0x1000
2658 #define PNG_FLAG_FREE_TRNS 0x2000
2659 #define PNG_FLAG_FREE_HIST 0x4000
2660 #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
2661 #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
2662 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
2663 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
2664 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
2665 #define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
2666 #define PNG_FLAG_ADD_ALPHA 0x200000L /* Added to libpng-1.2.8 */
2667 #define PNG_FLAG_STRIP_ALPHA 0x400000L /* Added to libpng-1.2.8 */
2668 /* 0x800000L unused */
2669 /* 0x1000000L unused */
2670 /* 0x2000000L unused */
2671 /* 0x4000000L unused */
2672 /* 0x8000000L unused */
2673 /* 0x10000000L unused */
2674 /* 0x20000000L unused */
2675 /* 0x40000000L unused */
2677 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
2678 PNG_FLAG_CRC_ANCILLARY_NOWARN)
2680 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
2681 PNG_FLAG_CRC_CRITICAL_IGNORE)
2683 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
2684 PNG_FLAG_CRC_CRITICAL_MASK)
2686 /* save typing and make code easier to understand */
2688 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
2689 abs((int)((c1).green) - (int)((c2).green)) + \
2690 abs((int)((c1).blue) - (int)((c2).blue)))
2692 /* Added to libpng-1.2.6 JB */
2693 #define PNG_ROWBYTES(pixel_bits, width) \
2694 ((pixel_bits) >= 8 ? \
2695 ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
2696 (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
2698 /* PNG_OUT_OF_RANGE returns true if value is outside the range
2699 ideal-delta..ideal+delta. Each argument is evaluated twice.
2700 "ideal" and "delta" should be constants, normally simple
2701 integers, "value" a variable. Added to libpng-1.2.6 JB */
2702 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
2703 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
2705 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
2706 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
2707 /* place to hold the signature string for a PNG file. */
2708 #ifdef PNG_USE_GLOBAL_ARRAYS
2709 PNG_EXPORT_VAR (const png_byte FARDATA) png_sig[8];
2711 #define png_sig png_sig_bytes(NULL)
2713 #endif /* PNG_NO_EXTERN */
2715 /* Constant strings for known chunk types. If you need to add a chunk,
2716 * define the name here, and add an invocation of the macro in png.c and
2717 * wherever it's needed.
2719 #define PNG_IHDR const png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
2720 #define PNG_IDAT const png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
2721 #define PNG_IEND const png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
2722 #define PNG_PLTE const png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
2723 #define PNG_bKGD const png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
2724 #define PNG_cHRM const png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
2725 #define PNG_gAMA const png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
2726 #define PNG_hIST const png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
2727 #define PNG_iCCP const png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
2728 #define PNG_iTXt const png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
2729 #define PNG_oFFs const png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
2730 #define PNG_pCAL const png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
2731 #define PNG_sCAL const png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
2732 #define PNG_pHYs const png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
2733 #define PNG_sBIT const png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
2734 #define PNG_sPLT const png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
2735 #define PNG_sRGB const png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
2736 #define PNG_tEXt const png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
2737 #define PNG_tIME const png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
2738 #define PNG_tRNS const png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
2739 #define PNG_zTXt const png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
2741 #ifdef PNG_USE_GLOBAL_ARRAYS
2742 PNG_EXPORT_VAR (const png_byte FARDATA) png_IHDR[5];
2743 PNG_EXPORT_VAR (const png_byte FARDATA) png_IDAT[5];
2744 PNG_EXPORT_VAR (const png_byte FARDATA) png_IEND[5];
2745 PNG_EXPORT_VAR (const png_byte FARDATA) png_PLTE[5];
2746 PNG_EXPORT_VAR (const png_byte FARDATA) png_bKGD[5];
2747 PNG_EXPORT_VAR (const png_byte FARDATA) png_cHRM[5];
2748 PNG_EXPORT_VAR (const png_byte FARDATA) png_gAMA[5];
2749 PNG_EXPORT_VAR (const png_byte FARDATA) png_hIST[5];
2750 PNG_EXPORT_VAR (const png_byte FARDATA) png_iCCP[5];
2751 PNG_EXPORT_VAR (const png_byte FARDATA) png_iTXt[5];
2752 PNG_EXPORT_VAR (const png_byte FARDATA) png_oFFs[5];
2753 PNG_EXPORT_VAR (const png_byte FARDATA) png_pCAL[5];
2754 PNG_EXPORT_VAR (const png_byte FARDATA) png_sCAL[5];
2755 PNG_EXPORT_VAR (const png_byte FARDATA) png_pHYs[5];
2756 PNG_EXPORT_VAR (const png_byte FARDATA) png_sBIT[5];
2757 PNG_EXPORT_VAR (const png_byte FARDATA) png_sPLT[5];
2758 PNG_EXPORT_VAR (const png_byte FARDATA) png_sRGB[5];
2759 PNG_EXPORT_VAR (const png_byte FARDATA) png_tEXt[5];
2760 PNG_EXPORT_VAR (const png_byte FARDATA) png_tIME[5];
2761 PNG_EXPORT_VAR (const png_byte FARDATA) png_tRNS[5];
2762 PNG_EXPORT_VAR (const png_byte FARDATA) png_zTXt[5];
2763 #endif /* PNG_USE_GLOBAL_ARRAYS */
2766 /* Inline macros to do direct reads of bytes from the input buffer. These
2767 * require that you are using an architecture that uses PNG byte ordering
2768 * (MSB first) and supports unaligned data storage. I think that PowerPC
2769 * in big-endian mode and 680x0 are the only ones that will support this.
2770 * The x86 line of processors definitely do not. The png_get_int_32()
2771 * routine also assumes we are using two's complement format for negative
2772 * values, which is almost certainly true.
2774 #if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
2775 # if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
2776 # define png_get_int_32(buf) ( *((png_int_32p) (buf)))
2778 # define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
2779 # define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
2781 # if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
2782 PNG_EXTERN png_int_32 png_get_int_32 PNGARG((png_bytep buf));
2784 PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf));
2785 PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf));
2786 #endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
2787 PNG_EXTERN png_uint_32 png_get_uint_31 PNGARG((png_structp png_ptr,
2790 /* Initialize png_ptr struct for reading, and allocate any other memory.
2791 * (old interface - DEPRECATED - use png_create_read_struct instead).
2793 extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
2794 #undef png_read_init
2795 #define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
2796 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2797 extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
2798 png_const_charp user_png_ver, png_size_t png_struct_size));
2799 extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
2800 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2803 /* Initialize png_ptr struct for writing, and allocate any other memory.
2804 * (old interface - DEPRECATED - use png_create_write_struct instead).
2806 extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
2807 #undef png_write_init
2808 #define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
2809 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2810 extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
2811 png_const_charp user_png_ver, png_size_t png_struct_size));
2812 extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
2813 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2816 /* Allocate memory for an internal libpng struct */
2817 PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
2819 /* Free memory from internal libpng struct */
2820 PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
2822 PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
2823 malloc_fn, png_voidp mem_ptr));
2824 PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
2825 png_free_ptr free_fn, png_voidp mem_ptr));
2827 /* Free any memory that info_ptr points to and reset struct. */
2828 PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
2829 png_infop info_ptr));
2832 /* Function to allocate memory for zlib. */
2833 PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
2835 /* Function to free memory for zlib */
2836 PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
2839 /* Function to convert a sizeof an item to png_sizeof item */
2840 PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
2843 /* Next four functions are used internally as callbacks. PNGAPI is required
2844 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
2846 PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
2847 png_bytep data, png_size_t length));
2849 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2850 PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
2851 png_bytep buffer, png_size_t length));
2854 PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
2855 png_bytep data, png_size_t length));
2857 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
2858 #if !defined(PNG_NO_STDIO)
2859 PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
2862 #else /* PNG_1_0_X */
2863 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2864 PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
2865 png_bytep buffer, png_size_t length));
2867 #endif /* PNG_1_0_X */
2869 /* Reset the CRC variable */
2870 PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
2872 /* Write the "data" buffer to whatever output you are using. */
2873 PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
2874 png_size_t length));
2876 /* Read data from whatever input you are using into the "data" buffer */
2877 PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
2878 png_size_t length));
2880 /* Read bytes into buf, and update png_ptr->crc */
2881 PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
2882 png_size_t length));
2884 /* Decompress data in a chunk that uses compression */
2885 #if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
2886 defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
2887 PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
2888 int comp_type, png_charp chunkdata, png_size_t chunklength,
2889 png_size_t prefix_length, png_size_t *data_length));
2892 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
2893 PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
2895 /* Read the CRC from the file and compare it to the libpng calculated CRC */
2896 PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
2898 /* Calculate the CRC over a section of data. Note that we are only
2899 * passing a maximum of 64K on systems that have this as a memory limit,
2900 * since this is the maximum buffer size we can specify.
2902 PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
2903 png_size_t length));
2905 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
2906 PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
2910 /* Place a 32-bit number into a buffer in PNG byte order (big-endian).
2911 * The only currently known PNG chunks that use signed numbers are
2912 * the ancillary extension chunks, oFFs and pCAL.
2914 PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i));
2916 #if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
2917 PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
2920 /* Place a 16-bit number into a buffer in PNG byte order.
2921 * The parameter is declared unsigned int, not png_uint_16,
2922 * just to avoid potential problems on pre-ANSI C compilers.
2924 PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i));
2926 /* simple function to write the signature */
2927 PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
2929 /* write various chunks */
2931 /* Write the IHDR chunk, and update the png_struct with the necessary
2934 PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
2936 int bit_depth, int color_type, int compression_method, int filter_method,
2937 int interlace_method));
2939 PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
2940 png_uint_32 num_pal));
2942 PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
2943 png_size_t length));
2945 PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
2947 #if defined(PNG_WRITE_gAMA_SUPPORTED)
2948 #ifdef PNG_FLOATING_POINT_SUPPORTED
2949 PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
2951 #ifdef PNG_FIXED_POINT_SUPPORTED
2952 PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
2957 #if defined(PNG_WRITE_sBIT_SUPPORTED)
2958 PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
2962 #if defined(PNG_WRITE_cHRM_SUPPORTED)
2963 #ifdef PNG_FLOATING_POINT_SUPPORTED
2964 PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
2965 double white_x, double white_y,
2966 double red_x, double red_y, double green_x, double green_y,
2967 double blue_x, double blue_y));
2969 #ifdef PNG_FIXED_POINT_SUPPORTED
2970 PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
2971 png_fixed_point int_white_x, png_fixed_point int_white_y,
2972 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2973 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2974 png_fixed_point int_blue_y));
2978 #if defined(PNG_WRITE_sRGB_SUPPORTED)
2979 PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
2983 #if defined(PNG_WRITE_iCCP_SUPPORTED)
2984 PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
2985 png_charp name, int compression_type,
2986 png_charp profile, int proflen));
2987 /* Note to maintainer: profile should be png_bytep */
2990 #if defined(PNG_WRITE_sPLT_SUPPORTED)
2991 PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
2992 png_sPLT_tp palette));
2995 #if defined(PNG_WRITE_tRNS_SUPPORTED)
2996 PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
2997 png_color_16p values, int number, int color_type));
3000 #if defined(PNG_WRITE_bKGD_SUPPORTED)
3001 PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
3002 png_color_16p values, int color_type));
3005 #if defined(PNG_WRITE_hIST_SUPPORTED)
3006 PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
3010 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
3011 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
3012 PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
3013 png_charp key, png_charpp new_key));
3016 #if defined(PNG_WRITE_tEXt_SUPPORTED)
3017 PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
3018 png_charp text, png_size_t text_len));
3021 #if defined(PNG_WRITE_zTXt_SUPPORTED)
3022 PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
3023 png_charp text, png_size_t text_len, int compression));
3026 #if defined(PNG_WRITE_iTXt_SUPPORTED)
3027 PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
3028 int compression, png_charp key, png_charp lang, png_charp lang_key,
3032 #if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
3033 PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
3034 png_infop info_ptr, png_textp text_ptr, int num_text));
3037 #if defined(PNG_WRITE_oFFs_SUPPORTED)
3038 PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
3039 png_int_32 x_offset, png_int_32 y_offset, int unit_type));
3042 #if defined(PNG_WRITE_pCAL_SUPPORTED)
3043 PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
3044 png_int_32 X0, png_int_32 X1, int type, int nparams,
3045 png_charp units, png_charpp params));
3048 #if defined(PNG_WRITE_pHYs_SUPPORTED)
3049 PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
3050 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
3054 #if defined(PNG_WRITE_tIME_SUPPORTED)
3055 PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
3056 png_timep mod_time));
3059 #if defined(PNG_WRITE_sCAL_SUPPORTED)
3060 #if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
3061 PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
3062 int unit, double width, double height));
3064 #ifdef PNG_FIXED_POINT_SUPPORTED
3065 PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
3066 int unit, png_charp width, png_charp height));
3071 /* Called when finished processing a row of data */
3072 PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
3074 /* Internal use only. Called before first row of data */
3075 PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
3077 #if defined(PNG_READ_GAMMA_SUPPORTED)
3078 PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
3081 /* combine a row of data, dealing with alpha, etc. if requested */
3082 PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
3085 #if defined(PNG_READ_INTERLACING_SUPPORTED)
3086 /* expand an interlaced row */
3087 /* OLD pre-1.0.9 interface:
3088 PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
3089 png_bytep row, int pass, png_uint_32 transformations));
3091 PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
3094 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
3096 #if defined(PNG_WRITE_INTERLACING_SUPPORTED)
3097 /* grab pixels out of a row for an interlaced pass */
3098 PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
3099 png_bytep row, int pass));
3102 /* unfilter a row */
3103 PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
3104 png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
3106 /* Choose the best filter to use and filter the row data */
3107 PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
3108 png_row_infop row_info));
3110 /* Write out the filtered row. */
3111 PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
3112 png_bytep filtered_row));
3113 /* finish a row while reading, dealing with interlacing passes, etc. */
3114 PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
3116 /* initialize the row buffers, etc. */
3117 PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
3118 /* optional call to update the users info structure */
3119 PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
3120 png_infop info_ptr));
3122 /* these are the functions that do the transformations */
3123 #if defined(PNG_READ_FILLER_SUPPORTED)
3124 PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
3125 png_bytep row, png_uint_32 filler, png_uint_32 flags));
3128 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
3129 PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
3133 #if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
3134 PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
3138 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
3139 PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
3143 #if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
3144 PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
3148 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
3149 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
3150 PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
3151 png_bytep row, png_uint_32 flags));
3154 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
3155 PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
3158 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
3159 PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
3162 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
3163 PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
3164 row_info, png_bytep row));
3167 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
3168 PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
3172 #if defined(PNG_READ_PACK_SUPPORTED)
3173 PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
3176 #if defined(PNG_READ_SHIFT_SUPPORTED)
3177 PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
3178 png_color_8p sig_bits));
3181 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
3182 PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
3185 #if defined(PNG_READ_16_TO_8_SUPPORTED)
3186 PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
3189 #if defined(PNG_READ_DITHER_SUPPORTED)
3190 PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
3191 png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
3193 # if defined(PNG_CORRECT_PALETTE_SUPPORTED)
3194 PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
3195 png_colorp palette, int num_palette));
3199 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
3200 PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
3203 #if defined(PNG_WRITE_PACK_SUPPORTED)
3204 PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
3205 png_bytep row, png_uint_32 bit_depth));
3208 #if defined(PNG_WRITE_SHIFT_SUPPORTED)
3209 PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
3210 png_color_8p bit_depth));
3213 #if defined(PNG_READ_BACKGROUND_SUPPORTED)
3214 #if defined(PNG_READ_GAMMA_SUPPORTED)
3215 PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3216 png_color_16p trans_values, png_color_16p background,
3217 png_color_16p background_1,
3218 png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
3219 png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
3220 png_uint_16pp gamma_16_to_1, int gamma_shift));
3222 PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3223 png_color_16p trans_values, png_color_16p background));
3227 #if defined(PNG_READ_GAMMA_SUPPORTED)
3228 PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
3229 png_bytep gamma_table, png_uint_16pp gamma_16_table,
3233 #if defined(PNG_READ_EXPAND_SUPPORTED)
3234 PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
3235 png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
3236 PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
3237 png_bytep row, png_color_16p trans_value));
3240 /* The following decodes the appropriate chunks, and does error correction,
3241 * then calls the appropriate callback for the chunk if it is valid.
3244 /* decode the IHDR chunk */
3245 PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
3246 png_uint_32 length));
3247 PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
3248 png_uint_32 length));
3249 PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
3250 png_uint_32 length));
3252 #if defined(PNG_READ_bKGD_SUPPORTED)
3253 PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
3254 png_uint_32 length));
3257 #if defined(PNG_READ_cHRM_SUPPORTED)
3258 PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
3259 png_uint_32 length));
3262 #if defined(PNG_READ_gAMA_SUPPORTED)
3263 PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
3264 png_uint_32 length));
3267 #if defined(PNG_READ_hIST_SUPPORTED)
3268 PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
3269 png_uint_32 length));
3272 #if defined(PNG_READ_iCCP_SUPPORTED)
3273 extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
3274 png_uint_32 length));
3275 #endif /* PNG_READ_iCCP_SUPPORTED */
3277 #if defined(PNG_READ_iTXt_SUPPORTED)
3278 PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3279 png_uint_32 length));
3282 #if defined(PNG_READ_oFFs_SUPPORTED)
3283 PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
3284 png_uint_32 length));
3287 #if defined(PNG_READ_pCAL_SUPPORTED)
3288 PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3289 png_uint_32 length));
3292 #if defined(PNG_READ_pHYs_SUPPORTED)
3293 PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
3294 png_uint_32 length));
3297 #if defined(PNG_READ_sBIT_SUPPORTED)
3298 PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
3299 png_uint_32 length));
3302 #if defined(PNG_READ_sCAL_SUPPORTED)
3303 PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3304 png_uint_32 length));
3307 #if defined(PNG_READ_sPLT_SUPPORTED)
3308 extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
3309 png_uint_32 length));
3310 #endif /* PNG_READ_sPLT_SUPPORTED */
3312 #if defined(PNG_READ_sRGB_SUPPORTED)
3313 PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
3314 png_uint_32 length));
3317 #if defined(PNG_READ_tEXt_SUPPORTED)
3318 PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3319 png_uint_32 length));
3322 #if defined(PNG_READ_tIME_SUPPORTED)
3323 PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
3324 png_uint_32 length));
3327 #if defined(PNG_READ_tRNS_SUPPORTED)
3328 PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
3329 png_uint_32 length));
3332 #if defined(PNG_READ_zTXt_SUPPORTED)
3333 PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3334 png_uint_32 length));
3337 PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
3338 png_infop info_ptr, png_uint_32 length));
3340 PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
3341 png_bytep chunk_name));
3343 /* handle the transformations for reading and writing */
3344 PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
3345 PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
3347 PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
3349 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3350 PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
3351 png_infop info_ptr));
3352 PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
3353 png_infop info_ptr));
3354 PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
3355 PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
3356 png_uint_32 length));
3357 PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
3358 PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
3359 PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
3360 png_bytep buffer, png_size_t buffer_length));
3361 PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
3362 PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
3363 png_bytep buffer, png_size_t buffer_length));
3364 PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
3365 PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
3366 png_infop info_ptr, png_uint_32 length));
3367 PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
3368 png_infop info_ptr));
3369 PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
3370 png_infop info_ptr));
3371 PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
3372 PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
3373 png_infop info_ptr));
3374 PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
3375 png_infop info_ptr));
3376 PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
3377 #if defined(PNG_READ_tEXt_SUPPORTED)
3378 PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
3379 png_infop info_ptr, png_uint_32 length));
3380 PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
3381 png_infop info_ptr));
3383 #if defined(PNG_READ_zTXt_SUPPORTED)
3384 PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
3385 png_infop info_ptr, png_uint_32 length));
3386 PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
3387 png_infop info_ptr));
3389 #if defined(PNG_READ_iTXt_SUPPORTED)
3390 PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
3391 png_infop info_ptr, png_uint_32 length));
3392 PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
3393 png_infop info_ptr));
3396 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
3398 #ifdef PNG_MNG_FEATURES_SUPPORTED
3399 PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
3401 PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
3405 #if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
3406 /* png.c */ /* PRIVATE */
3407 PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
3409 /* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
3411 #endif /* PNG_INTERNAL */
3417 #endif /* PNG_VERSION_INFO_ONLY */
3418 /* do not put anything past this line */
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