/* png.h - header file for PNG reference library
*
- * libpng version 1.0.3 - January 14, 1999
- * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
- * Copyright (c) 1996, 1997 Andreas Dilger
- * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ * libpng version 1.6.2 - April 25, 2013
+ * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*
- * Y2K compliance in libpng:
- * =========================
+ * This code is released under the libpng license (See LICENSE, below)
*
- * January 13, 1999
+ * Authors and maintainers:
+ * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
+ * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
+ * libpng versions 0.97, January 1998, through 1.6.2 - April 25, 2013: Glenn
+ * See also "Contributing Authors", below.
*
- * Since the PNG Development group is an ad-hoc body, we can't make
- * an official declaration.
+ * Note about libpng version numbers:
*
- * This is your unofficial assurance that libpng from version 0.81 and
- * upward are Y2K compliant. It is my belief that earlier versions were
- * also Y2K compliant.
+ * Due to various miscommunications, unforeseen code incompatibilities
+ * and occasional factors outside the authors' control, version numbering
+ * on the library has not always been consistent and straightforward.
+ * The following table summarizes matters since version 0.89c, which was
+ * the first widely used release:
*
- * Libpng only has three year fields. One is a 2-byte unsigned integer
- * that will hold years up to 65535. The other two hold the date in text
- * format, and will hold years up to 9999.
+ * source png.h png.h shared-lib
+ * version string int version
+ * ------- ------ ----- ----------
+ * 0.89c "1.0 beta 3" 0.89 89 1.0.89
+ * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]
+ * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]
+ * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]
+ * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]
+ * 0.97c 0.97 97 2.0.97
+ * 0.98 0.98 98 2.0.98
+ * 0.99 0.99 98 2.0.99
+ * 0.99a-m 0.99 99 2.0.99
+ * 1.00 1.00 100 2.1.0 [100 should be 10000]
+ * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]
+ * 1.0.1 png.h string is 10001 2.1.0
+ * 1.0.1a-e identical to the 10002 from here on, the shared library
+ * 1.0.2 source version) 10002 is 2.V where V is the source code
+ * 1.0.2a-b 10003 version, except as noted.
+ * 1.0.3 10003
+ * 1.0.3a-d 10004
+ * 1.0.4 10004
+ * 1.0.4a-f 10005
+ * 1.0.5 (+ 2 patches) 10005
+ * 1.0.5a-d 10006
+ * 1.0.5e-r 10100 (not source compatible)
+ * 1.0.5s-v 10006 (not binary compatible)
+ * 1.0.6 (+ 3 patches) 10006 (still binary incompatible)
+ * 1.0.6d-f 10007 (still binary incompatible)
+ * 1.0.6g 10007
+ * 1.0.6h 10007 10.6h (testing xy.z so-numbering)
+ * 1.0.6i 10007 10.6i
+ * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)
+ * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)
+ * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)
+ * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)
+ * 1.0.7 1 10007 (still compatible)
+ * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4
+ * 1.0.8rc1 1 10008 2.1.0.8rc1
+ * 1.0.8 1 10008 2.1.0.8
+ * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6
+ * 1.0.9rc1 1 10009 2.1.0.9rc1
+ * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10
+ * 1.0.9rc2 1 10009 2.1.0.9rc2
+ * 1.0.9 1 10009 2.1.0.9
+ * 1.0.10beta1 1 10010 2.1.0.10beta1
+ * 1.0.10rc1 1 10010 2.1.0.10rc1
+ * 1.0.10 1 10010 2.1.0.10
+ * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3
+ * 1.0.11rc1 1 10011 2.1.0.11rc1
+ * 1.0.11 1 10011 2.1.0.11
+ * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2
+ * 1.0.12rc1 2 10012 2.1.0.12rc1
+ * 1.0.12 2 10012 2.1.0.12
+ * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned)
+ * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2
+ * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5
+ * 1.2.0rc1 3 10200 3.1.2.0rc1
+ * 1.2.0 3 10200 3.1.2.0
+ * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4
+ * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2
+ * 1.2.1 3 10201 3.1.2.1
+ * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6
+ * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1
+ * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1
+ * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1
+ * 1.0.13 10 10013 10.so.0.1.0.13
+ * 1.2.2 12 10202 12.so.0.1.2.2
+ * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6
+ * 1.2.3 12 10203 12.so.0.1.2.3
+ * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3
+ * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1
+ * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1
+ * 1.0.14 10 10014 10.so.0.1.0.14
+ * 1.2.4 13 10204 12.so.0.1.2.4
+ * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2
+ * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3
+ * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3
+ * 1.0.15 10 10015 10.so.0.1.0.15
+ * 1.2.5 13 10205 12.so.0.1.2.5
+ * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4
+ * 1.0.16 10 10016 10.so.0.1.0.16
+ * 1.2.6 13 10206 12.so.0.1.2.6
+ * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2
+ * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1
+ * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1
+ * 1.0.17 10 10017 12.so.0.1.0.17
+ * 1.2.7 13 10207 12.so.0.1.2.7
+ * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5
+ * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5
+ * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5
+ * 1.0.18 10 10018 12.so.0.1.0.18
+ * 1.2.8 13 10208 12.so.0.1.2.8
+ * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3
+ * 1.2.9beta4-11 13 10209 12.so.0.9[.0]
+ * 1.2.9rc1 13 10209 12.so.0.9[.0]
+ * 1.2.9 13 10209 12.so.0.9[.0]
+ * 1.2.10beta1-7 13 10210 12.so.0.10[.0]
+ * 1.2.10rc1-2 13 10210 12.so.0.10[.0]
+ * 1.2.10 13 10210 12.so.0.10[.0]
+ * 1.4.0beta1-5 14 10400 14.so.0.0[.0]
+ * 1.2.11beta1-4 13 10211 12.so.0.11[.0]
+ * 1.4.0beta7-8 14 10400 14.so.0.0[.0]
+ * 1.2.11 13 10211 12.so.0.11[.0]
+ * 1.2.12 13 10212 12.so.0.12[.0]
+ * 1.4.0beta9-14 14 10400 14.so.0.0[.0]
+ * 1.2.13 13 10213 12.so.0.13[.0]
+ * 1.4.0beta15-36 14 10400 14.so.0.0[.0]
+ * 1.4.0beta37-87 14 10400 14.so.14.0[.0]
+ * 1.4.0rc01 14 10400 14.so.14.0[.0]
+ * 1.4.0beta88-109 14 10400 14.so.14.0[.0]
+ * 1.4.0rc02-08 14 10400 14.so.14.0[.0]
+ * 1.4.0 14 10400 14.so.14.0[.0]
+ * 1.4.1beta01-03 14 10401 14.so.14.1[.0]
+ * 1.4.1rc01 14 10401 14.so.14.1[.0]
+ * 1.4.1beta04-12 14 10401 14.so.14.1[.0]
+ * 1.4.1 14 10401 14.so.14.1[.0]
+ * 1.4.2 14 10402 14.so.14.2[.0]
+ * 1.4.3 14 10403 14.so.14.3[.0]
+ * 1.4.4 14 10404 14.so.14.4[.0]
+ * 1.5.0beta01-58 15 10500 15.so.15.0[.0]
+ * 1.5.0rc01-07 15 10500 15.so.15.0[.0]
+ * 1.5.0 15 10500 15.so.15.0[.0]
+ * 1.5.1beta01-11 15 10501 15.so.15.1[.0]
+ * 1.5.1rc01-02 15 10501 15.so.15.1[.0]
+ * 1.5.1 15 10501 15.so.15.1[.0]
+ * 1.5.2beta01-03 15 10502 15.so.15.2[.0]
+ * 1.5.2rc01-03 15 10502 15.so.15.2[.0]
+ * 1.5.2 15 10502 15.so.15.2[.0]
+ * 1.5.3beta01-10 15 10503 15.so.15.3[.0]
+ * 1.5.3rc01-02 15 10503 15.so.15.3[.0]
+ * 1.5.3beta11 15 10503 15.so.15.3[.0]
+ * 1.5.3 [omitted]
+ * 1.5.4beta01-08 15 10504 15.so.15.4[.0]
+ * 1.5.4rc01 15 10504 15.so.15.4[.0]
+ * 1.5.4 15 10504 15.so.15.4[.0]
+ * 1.5.5beta01-08 15 10505 15.so.15.5[.0]
+ * 1.5.5rc01 15 10505 15.so.15.5[.0]
+ * 1.5.5 15 10505 15.so.15.5[.0]
+ * 1.5.6beta01-07 15 10506 15.so.15.6[.0]
+ * 1.5.6rc01-03 15 10506 15.so.15.6[.0]
+ * 1.5.6 15 10506 15.so.15.6[.0]
+ * 1.5.7beta01-05 15 10507 15.so.15.7[.0]
+ * 1.5.7rc01-03 15 10507 15.so.15.7[.0]
+ * 1.5.7 15 10507 15.so.15.7[.0]
+ * 1.6.0beta01-40 16 10600 16.so.16.0[.0]
+ * 1.6.0rc01-08 16 10600 16.so.16.0[.0]
+ * 1.6.0 16 10600 16.so.16.0[.0]
+ * 1.6.1beta01-09 16 10601 16.so.16.1[.0]
+ * 1.6.1rc01 16 10601 16.so.16.1[.0]
+ * 1.6.1 16 10601 16.so.16.1[.0]
+ * 1.6.2beta01 16 10602 16.so.16.2[.0]
+ * 1.6.2rc01-06 16 10602 16.so.16.2[.0]
+ * 1.6.2 16 10602 16.so.16.2[.0]
*
- * The integer is
- * "png_uint_16 year" in png_time_struct.
+ * Henceforth the source version will match the shared-library major
+ * and minor numbers; the shared-library major version number will be
+ * used for changes in backward compatibility, as it is intended. The
+ * PNG_LIBPNG_VER macro, which is not used within libpng but is available
+ * for applications, is an unsigned integer of the form xyyzz corresponding
+ * to the source version x.y.z (leading zeros in y and z). Beta versions
+ * were given the previous public release number plus a letter, until
+ * version 1.0.6j; from then on they were given the upcoming public
+ * release number plus "betaNN" or "rcNN".
*
- * The strings are
- * "png_charp time_buffer" in png_struct and
- * "near_time_buffer", which is a local character string in png.c.
+ * Binary incompatibility exists only when applications make direct access
+ * to the info_ptr or png_ptr members through png.h, and the compiled
+ * application is loaded with a different version of the library.
*
- * There are seven time-related functions:
- * png.c: png_convert_to_rfc_1123() in png.c
- * (formerly png_convert_to_rfc_1152() in error)
- * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
- * png_convert_from_time_t() in pngwrite.c
- * png_get_tIME() in pngget.c
- * png_handle_tIME() in pngrutil.c, called in pngread.c
- * png_set_tIME() in pngset.c
- * png_write_tIME() in pngwutil.c, called in pngwrite.c
+ * DLLNUM will change each time there are forward or backward changes
+ * in binary compatibility (e.g., when a new feature is added).
*
- * All handle dates properly in a Y2K environment. The
- * png_convert_from_time_t() function calls gmtime() to convert from system
- * clock time, which returns (year - 1900), which we properly convert to
- * the full 4-digit year. There is a possibility that applications using
- * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
- * function, or incorrectly passing only a 2-digit year instead of
- * "year - 1900" into the png_convert_from_struct_tm() function, but this
- * is not under our control. The libpng documentation has always stated
- * that it works with 4-digit years, and the APIs have been documented as
- * such.
+ * See libpng-manual.txt or libpng.3 for more information. The PNG
+ * specification is available as a W3C Recommendation and as an ISO
+ * Specification, <http://www.w3.org/TR/2003/REC-PNG-20031110/
+ */
+
+/*
+ * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
*
- * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
- * integer to hold the year, and can hold years as large as 65535.
+ * If you modify libpng you may insert additional notices immediately following
+ * this sentence.
*
+ * This code is released under the libpng license.
*
- * Glenn Randers-Pehrson
- * libpng maintainer
- * PNG Development Group
+ * libpng versions 1.2.6, August 15, 2004, through 1.6.2, April 25, 2013, are
+ * Copyright (c) 2004, 2006-2013 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.2.5
+ * with the following individual added to the list of Contributing Authors:
*
- * Note about libpng version numbers:
+ * Cosmin Truta
+ *
+ * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
+ * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.0.6
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ * Simon-Pierre Cadieux
+ * Eric S. Raymond
+ * Gilles Vollant
+ *
+ * and with the following additions to the disclaimer:
+ *
+ * There is no warranty against interference with your enjoyment of the
+ * library or against infringement. There is no warranty that our
+ * efforts or the library will fulfill any of your particular purposes
+ * or needs. This library is provided with all faults, and the entire
+ * risk of satisfactory quality, performance, accuracy, and effort is with
+ * the user.
+ *
+ * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
+ * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-0.96,
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ * Tom Lane
+ * Glenn Randers-Pehrson
+ * Willem van Schaik
+ *
+ * libpng versions 0.89, June 1996, through 0.96, May 1997, are
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Distributed according to the same disclaimer and license as libpng-0.88,
+ * with the following individuals added to the list of Contributing Authors:
*
- * Due to various miscommunications, unforeseen code incompatibilities
- * and occasional factors outside the authors' control, version numbering
- * on the library has not always been consistent and straightforward.
- * The following table summarizes matters since version 0.89c, which was
- * the first widely used release:
- *
- * source png.h png.h shared-lib
- * version string int version
- * ------- ------ ----- ----------
- * 0.89c ("1.0 beta 3") 0.89 89 1.0.89
- * 0.90 ("1.0 beta 4") 0.90 90 0.90 [should have been 2.0.90]
- * 0.95 ("1.0 beta 5") 0.95 95 0.95 [should have been 2.0.95]
- * 0.96 ("1.0 beta 6") 0.96 96 0.96 [should have been 2.0.96]
- * 0.97b ("1.00.97 beta 7") 1.00.97 97 1.0.1 [should have been 2.0.97]
- * 0.97c 0.97 97 2.0.97
- * 0.98 0.98 98 2.0.98
- * 0.99 0.99 98 2.0.99
- * 0.99a-m 0.99 99 2.0.99
- * 1.00 1.00 100 2.1.0 [int should be 10000]
- * 1.0.0 1.0.0 100 2.1.0 [int should be 10000]
- * 1.0.1 1.0.1 10001 2.1.0
- * 1.0.1a-e 1.0.1a-e 10002 2.1.0.1a-e
- * 1.0.2 1.0.2 10002 2.1.0.2
- * 1.0.2a-c 1.0.2a 10003 2.1.0.2a-c
- * 1.0.3 1.0.3 10003 2.1.0.3
- *
- * Henceforth the source version will match the shared-library minor
- * and patch numbers; the shared-library major version number will be
- * used for changes in backward compatibility, as it is intended. The
- * PNG_PNGLIB_VER macro, which is not used within libpng but is available
- * for applications, is an unsigned integer of the form xyyzz corresponding
- * to the source version x.y.z (leading zeros in y and z).
- *
- * See libpng.txt or libpng.3 for more information. The PNG specification
- * is available as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/>
- * and as a W3C Recommendation <http://www.w3.org/TR/REC.png.html>
- *
- * Contributing Authors:
* John Bowler
* Kevin Bracey
* Sam Bushell
- * Andreas Dilger
* Magnus Holmgren
- * Tom Lane
- * Dave Martindale
- * Glenn Randers-Pehrson
* Greg Roelofs
- * Guy Eric Schalnat
- * Paul Schmidt
* Tom Tanner
- * Willem van Schaik
- * Tim Wegner
*
- * The contributing authors would like to thank all those who helped
- * with testing, bug fixes, and patience. This wouldn't have been
- * possible without all of you.
+ * libpng versions 0.5, May 1995, through 0.88, January 1996, are
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
*
- * Thanks to Frank J. T. Wojcik for helping with the documentation.
+ * For the purposes of this copyright and license, "Contributing Authors"
+ * is defined as the following set of individuals:
*
- * COPYRIGHT NOTICE:
+ * Andreas Dilger
+ * Dave Martindale
+ * Guy Eric Schalnat
+ * Paul Schmidt
+ * Tim Wegner
*
* The PNG Reference Library is supplied "AS IS". The Contributing Authors
* and Group 42, Inc. disclaim all warranties, expressed or implied,
* Permission is hereby granted to use, copy, modify, and distribute this
* source code, or portions hereof, for any purpose, without fee, subject
* to the following restrictions:
- * 1. The origin of this source code must not be misrepresented.
- * 2. Altered versions must be plainly marked as such and must not be
- * misrepresented as being the original source.
- * 3. This Copyright notice may not be removed or altered from any source or
- * altered source distribution.
+ *
+ * 1. The origin of this source code must not be misrepresented.
+ *
+ * 2. Altered versions must be plainly marked as such and must not
+ * be misrepresented as being the original source.
+ *
+ * 3. This Copyright notice may not be removed or altered from
+ * any source or altered source distribution.
*
* The Contributing Authors and Group 42, Inc. specifically permit, without
* fee, and encourage the use of this source code as a component to
* appreciated.
*/
+/*
+ * A "png_get_copyright" function is available, for convenient use in "about"
+ * boxes and the like:
+ *
+ * printf("%s", png_get_copyright(NULL));
+ *
+ * Also, the PNG logo (in PNG format, of course) is supplied in the
+ * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+ */
-#ifndef _PNG_H
-#define _PNG_H
+/*
+ * Libpng is OSI Certified Open Source Software. OSI Certified is a
+ * certification mark of the Open Source Initiative.
+ */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
+/*
+ * The contributing authors would like to thank all those who helped
+ * with testing, bug fixes, and patience. This wouldn't have been
+ * possible without all of you.
+ *
+ * Thanks to Frank J. T. Wojcik for helping with the documentation.
+ */
+
+/*
+ * Y2K compliance in libpng:
+ * =========================
+ *
+ * April 25, 2013
+ *
+ * Since the PNG Development group is an ad-hoc body, we can't make
+ * an official declaration.
+ *
+ * This is your unofficial assurance that libpng from version 0.71 and
+ * upward through 1.6.2 are Y2K compliant. It is my belief that
+ * earlier versions were also Y2K compliant.
+ *
+ * Libpng only has two year fields. One is a 2-byte unsigned integer
+ * that will hold years up to 65535. The other, which is deprecated,
+ * holds the date in text format, and will hold years up to 9999.
+ *
+ * The integer is
+ * "png_uint_16 year" in png_time_struct.
+ *
+ * The string is
+ * "char time_buffer[29]" in png_struct. This is no longer used
+ * in libpng-1.6.x and will be removed from libpng-1.7.0.
+ *
+ * There are seven time-related functions:
+ * png.c: png_convert_to_rfc_1123_buffer() in png.c
+ * (formerly png_convert_to_rfc_1123() prior to libpng-1.5.x and
+ * png_convert_to_rfc_1152() in error prior to libpng-0.98)
+ * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
+ * png_convert_from_time_t() in pngwrite.c
+ * png_get_tIME() in pngget.c
+ * png_handle_tIME() in pngrutil.c, called in pngread.c
+ * png_set_tIME() in pngset.c
+ * png_write_tIME() in pngwutil.c, called in pngwrite.c
+ *
+ * All handle dates properly in a Y2K environment. The
+ * png_convert_from_time_t() function calls gmtime() to convert from system
+ * clock time, which returns (year - 1900), which we properly convert to
+ * the full 4-digit year. There is a possibility that libpng applications
+ * are not passing 4-digit years into the png_convert_to_rfc_1123_buffer()
+ * function, or that they are incorrectly passing only a 2-digit year
+ * instead of "year - 1900" into the png_convert_from_struct_tm() function,
+ * but this is not under our control. The libpng documentation has always
+ * stated that it works with 4-digit years, and the APIs have been
+ * documented as such.
+ *
+ * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
+ * integer to hold the year, and can hold years as large as 65535.
+ *
+ * zlib, upon which libpng depends, is also Y2K compliant. It contains
+ * no date-related code.
+ *
+ * Glenn Randers-Pehrson
+ * libpng maintainer
+ * PNG Development Group
+ */
-/* This is not the place to learn how to use libpng. The file libpng.txt
+#ifndef PNG_H
+#define PNG_H
+
+/* This is not the place to learn how to use libpng. The file libpng-manual.txt
* describes how to use libpng, and the file example.c summarizes it
* with some code on which to build. This file is useful for looking
* at the actual function definitions and structure components.
+ *
+ * If you just need to read a PNG file and don't want to read the documentation
+ * skip to the end of this file and read the section entitled 'simplified API'.
*/
-/* include the compression library's header */
-#include "zlib.h"
+/* Version information for png.h - this should match the version in png.c */
+#define PNG_LIBPNG_VER_STRING "1.6.2"
+#define PNG_HEADER_VERSION_STRING \
+ " libpng version 1.6.2 - April 25, 2013\n"
+
+#define PNG_LIBPNG_VER_SONUM 16
+#define PNG_LIBPNG_VER_DLLNUM 16
-/* include all user configurable info */
-#include "pngconf.h"
+/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
+#define PNG_LIBPNG_VER_MAJOR 1
+#define PNG_LIBPNG_VER_MINOR 6
+#define PNG_LIBPNG_VER_RELEASE 2
-/* This file is arranged in several sections. The first section contains
- * structure and type definitions. The second section contains the external
- * library functions, while the third has the internal library functions,
- * which applications aren't expected to use directly.
+/* This should match the numeric part of the final component of
+ * PNG_LIBPNG_VER_STRING, omitting any leading zero:
*/
-/* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.0.3"
+#define PNG_LIBPNG_VER_BUILD 0
+
+/* Release Status */
+#define PNG_LIBPNG_BUILD_ALPHA 1
+#define PNG_LIBPNG_BUILD_BETA 2
+#define PNG_LIBPNG_BUILD_RC 3
+#define PNG_LIBPNG_BUILD_STABLE 4
+#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
+
+/* Release-Specific Flags */
+#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with
+ PNG_LIBPNG_BUILD_STABLE only */
+#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
+ PNG_LIBPNG_BUILD_SPECIAL */
+#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
+ PNG_LIBPNG_BUILD_PRIVATE */
+
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
* We must not include leading zeros.
* Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
* version 1.0.0 was mis-numbered 100 instead of 10000). From
- * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=bugfix */
-#define PNG_LIBPNG_VER 10003 /* 1.0.3 */
+ * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release
+ */
+#define PNG_LIBPNG_VER 10602 /* 1.6.2 */
+
+/* Library configuration: these options cannot be changed after
+ * the library has been built.
+ */
+#ifndef PNGLCONF_H
+ /* If pnglibconf.h is missing, you can
+ * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
+ */
+# include "pnglibconf.h"
+#endif
+
+#ifndef PNG_VERSION_INFO_ONLY
+ /* Machine specific configuration. */
+# include "pngconf.h"
+#endif
+
+/*
+ * Added at libpng-1.2.8
+ *
+ * Ref MSDN: Private as priority over Special
+ * VS_FF_PRIVATEBUILD File *was not* built using standard release
+ * procedures. If this value is given, the StringFileInfo block must
+ * contain a PrivateBuild string.
+ *
+ * VS_FF_SPECIALBUILD File *was* built by the original company using
+ * standard release procedures but is a variation of the standard
+ * file of the same version number. If this value is given, the
+ * StringFileInfo block must contain a SpecialBuild string.
+ */
+
+#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
+# define PNG_LIBPNG_BUILD_TYPE \
+ (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
+#else
+# ifdef PNG_LIBPNG_SPECIALBUILD
+# define PNG_LIBPNG_BUILD_TYPE \
+ (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
+# else
+# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
+# endif
+#endif
+
+#ifndef PNG_VERSION_INFO_ONLY
+
+/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
-/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
-#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
/* Version information for C files, stored in png.c. This had better match
* the version above.
*/
-extern char png_libpng_ver[12]; /* need room for 99.99.99aa */
-
-/* Structures to facilitate easy interlacing. See png.c for more details */
-extern int FARDATA png_pass_start[7];
-extern int FARDATA png_pass_inc[7];
-extern int FARDATA png_pass_ystart[7];
-extern int FARDATA png_pass_yinc[7];
-extern int FARDATA png_pass_mask[7];
-extern int FARDATA png_pass_dsp_mask[7];
-/* These aren't currently used. If you need them, see png.c for more details
-extern int FARDATA png_pass_width[7];
-extern int FARDATA png_pass_height[7];
-*/
+#define png_libpng_ver png_get_header_ver(NULL)
+
+/* This file is arranged in several sections:
+ *
+ * 1. Any configuration options that can be specified by for the application
+ * code when it is built. (Build time configuration is in pnglibconf.h)
+ * 2. Type definitions (base types are defined in pngconf.h), structure
+ * definitions.
+ * 3. Exported library functions.
+ * 4. Simplified API.
+ *
+ * The library source code has additional files (principally pngpriv.h) that
+ * allow configuration of the library.
+ */
+/* Section 1: run time configuration
+ * See pnglibconf.h for build time configuration
+ *
+ * Run time configuration allows the application to choose between
+ * implementations of certain arithmetic APIs. The default is set
+ * at build time and recorded in pnglibconf.h, but it is safe to
+ * override these (and only these) settings. Note that this won't
+ * change what the library does, only application code, and the
+ * settings can (and probably should) be made on a per-file basis
+ * by setting the #defines before including png.h
+ *
+ * Use macros to read integers from PNG data or use the exported
+ * functions?
+ * PNG_USE_READ_MACROS: use the macros (see below) Note that
+ * the macros evaluate their argument multiple times.
+ * PNG_NO_USE_READ_MACROS: call the relevant library function.
+ *
+ * Use the alternative algorithm for compositing alpha samples that
+ * does not use division?
+ * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division'
+ * algorithm.
+ * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm.
+ *
+ * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is
+ * false?
+ * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error
+ * APIs to png_warning.
+ * Otherwise the calls are mapped to png_error.
+ */
+
+/* Section 2: type definitions, including structures and compile time
+ * constants.
+ * See pngconf.h for base types that vary by machine/system
+ */
+
+/* This triggers a compiler error in png.c, if png.c and png.h
+ * do not agree upon the version number.
+ */
+typedef char* png_libpng_version_1_6_2;
-#endif /* PNG_NO_EXTERN */
+/* Basic control structions. Read libpng-manual.txt or libpng.3 for more info.
+ *
+ * png_struct is the cache of information used while reading or writing a single
+ * PNG file. One of these is always required, although the simplified API
+ * (below) hides the creation and destruction of it.
+ */
+typedef struct png_struct_def png_struct;
+typedef const png_struct * png_const_structp;
+typedef png_struct * png_structp;
+typedef png_struct * * png_structpp;
+
+/* png_info contains information read from or to be written to a PNG file. One
+ * or more of these must exist while reading or creating a PNG file. The
+ * information is not used by libpng during read but is used to control what
+ * gets written when a PNG file is created. "png_get_" function calls read
+ * information during read and "png_set_" functions calls write information
+ * when creating a PNG.
+ * been moved into a separate header file that is not accessible to
+ * applications. Read libpng-manual.txt or libpng.3 for more info.
+ */
+typedef struct png_info_def png_info;
+typedef png_info * png_infop;
+typedef const png_info * png_const_infop;
+typedef png_info * * png_infopp;
+
+/* Types with names ending 'p' are pointer types. The corresponding types with
+ * names ending 'rp' are identical pointer types except that the pointer is
+ * marked 'restrict', which means that it is the only pointer to the object
+ * passed to the function. Applications should not use the 'restrict' types;
+ * it is always valid to pass 'p' to a pointer with a function argument of the
+ * corresponding 'rp' type. Different compilers have different rules with
+ * regard to type matching in the presence of 'restrict'. For backward
+ * compatibility libpng callbacks never have 'restrict' in their parameters and,
+ * consequentially, writing portable application code is extremely difficult if
+ * an attempt is made to use 'restrict'.
+ */
+typedef png_struct * PNG_RESTRICT png_structrp;
+typedef const png_struct * PNG_RESTRICT png_const_structrp;
+typedef png_info * PNG_RESTRICT png_inforp;
+typedef const png_info * PNG_RESTRICT png_const_inforp;
/* Three color definitions. The order of the red, green, and blue, (and the
* exact size) is not important, although the size of the fields need to
png_byte green;
png_byte blue;
} png_color;
-typedef png_color FAR * png_colorp;
-typedef png_color FAR * FAR * png_colorpp;
+typedef png_color * png_colorp;
+typedef const png_color * png_const_colorp;
+typedef png_color * * png_colorpp;
typedef struct png_color_16_struct
{
png_uint_16 blue;
png_uint_16 gray; /* for use in grayscale files */
} png_color_16;
-typedef png_color_16 FAR * png_color_16p;
-typedef png_color_16 FAR * FAR * png_color_16pp;
+typedef png_color_16 * png_color_16p;
+typedef const png_color_16 * png_const_color_16p;
+typedef png_color_16 * * png_color_16pp;
typedef struct png_color_8_struct
{
png_byte gray; /* for use in grayscale files */
png_byte alpha; /* for alpha channel files */
} png_color_8;
-typedef png_color_8 FAR * png_color_8p;
-typedef png_color_8 FAR * FAR * png_color_8pp;
+typedef png_color_8 * png_color_8p;
+typedef const png_color_8 * png_const_color_8p;
+typedef png_color_8 * * png_color_8pp;
-/* png_text holds the text in a PNG file, and whether they are compressed
- in the PNG file or not. The "text" field points to a regular C string. */
+/*
+ * The following two structures are used for the in-core representation
+ * of sPLT chunks.
+ */
+typedef struct png_sPLT_entry_struct
+{
+ png_uint_16 red;
+ png_uint_16 green;
+ png_uint_16 blue;
+ png_uint_16 alpha;
+ png_uint_16 frequency;
+} png_sPLT_entry;
+typedef png_sPLT_entry * png_sPLT_entryp;
+typedef const png_sPLT_entry * png_const_sPLT_entryp;
+typedef png_sPLT_entry * * png_sPLT_entrypp;
+
+/* When the depth of the sPLT palette is 8 bits, the color and alpha samples
+ * occupy the LSB of their respective members, and the MSB of each member
+ * is zero-filled. The frequency member always occupies the full 16 bits.
+ */
+
+typedef struct png_sPLT_struct
+{
+ png_charp name; /* palette name */
+ png_byte depth; /* depth of palette samples */
+ png_sPLT_entryp entries; /* palette entries */
+ png_int_32 nentries; /* number of palette entries */
+} png_sPLT_t;
+typedef png_sPLT_t * png_sPLT_tp;
+typedef const png_sPLT_t * png_const_sPLT_tp;
+typedef png_sPLT_t * * png_sPLT_tpp;
+
+#ifdef PNG_TEXT_SUPPORTED
+/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
+ * and whether that contents is compressed or not. The "key" field
+ * points to a regular zero-terminated C string. The "text" fields can be a
+ * regular C string, an empty string, or a NULL pointer.
+ * However, the structure returned by png_get_text() will always contain
+ * the "text" field as a regular zero-terminated C string (possibly
+ * empty), never a NULL pointer, so it can be safely used in printf() and
+ * other string-handling functions. Note that the "itxt_length", "lang", and
+ * "lang_key" members of the structure only exist when the library is built
+ * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by
+ * default without iTXt support. Also note that when iTXt *is* supported,
+ * the "lang" and "lang_key" fields contain NULL pointers when the
+ * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or
+ * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the
+ * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"
+ * which is always 0 or 1, or its "compression method" which is always 0.
+ */
typedef struct png_text_struct
{
- int compression; /* compression value, see PNG_TEXT_COMPRESSION_ */
+ int compression; /* compression value:
+ -1: tEXt, none
+ 0: zTXt, deflate
+ 1: iTXt, none
+ 2: iTXt, deflate */
png_charp key; /* keyword, 1-79 character description of "text" */
- png_charp text; /* comment, may be an empty string (ie "") */
- png_size_t text_length; /* length of "text" field */
+ png_charp text; /* comment, may be an empty string (ie "")
+ or a NULL pointer */
+ png_size_t text_length; /* length of the text string */
+ png_size_t itxt_length; /* length of the itxt string */
+ png_charp lang; /* language code, 0-79 characters
+ or a NULL pointer */
+ png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
+ chars or a NULL pointer */
} png_text;
-typedef png_text FAR * png_textp;
-typedef png_text FAR * FAR * png_textpp;
+typedef png_text * png_textp;
+typedef const png_text * png_const_textp;
+typedef png_text * * png_textpp;
+#endif
/* Supported compression types for text in PNG files (tEXt, and zTXt).
* The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
#define PNG_TEXT_COMPRESSION_zTXt_WR -2
#define PNG_TEXT_COMPRESSION_NONE -1
#define PNG_TEXT_COMPRESSION_zTXt 0
-#define PNG_TEXT_COMPRESSION_LAST 1 /* Not a valid value */
+#define PNG_ITXT_COMPRESSION_NONE 1
+#define PNG_ITXT_COMPRESSION_zTXt 2
+#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
/* png_time is a way to hold the time in an machine independent way.
* Two conversions are provided, both from time_t and struct tm. There
* is no portable way to convert to either of these structures, as far
* as I know. If you know of a portable way, send it to me. As a side
- * note - PNG is Year 2000 compliant!
+ * note - PNG has always been Year 2000 compliant!
*/
typedef struct png_time_struct
{
png_byte minute; /* minute of hour, 0 - 59 */
png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
} png_time;
-typedef png_time FAR * png_timep;
-typedef png_time FAR * FAR * png_timepp;
-
-/* png_info is a structure that holds the information in a PNG file so
- * that the application can find out the characteristics of the image.
- * If you are reading the file, this structure will tell you what is
- * in the PNG file. If you are writing the file, fill in the information
- * you want to put into the PNG file, then call png_write_info().
- * The names chosen should be very close to the PNG specification, so
- * consult that document for information about the meaning of each field.
- *
- * With libpng < 0.95, it was only possible to directly set and read the
- * the values in the png_info_struct, which meant that the contents and
- * order of the values had to remain fixed. With libpng 0.95 and later,
- * however, there are now functions that abstract the contents of
- * png_info_struct from the application, so this makes it easier to use
- * libpng with dynamic libraries, and even makes it possible to use
- * libraries that don't have all of the libpng ancillary chunk-handing
- * functionality.
- *
- * In any case, the order of the parameters in png_info_struct should NOT
- * be changed for as long as possible to keep compatibility with applications
- * that use the old direct-access method with png_info_struct.
- */
-typedef struct png_info_struct
+typedef png_time * png_timep;
+typedef const png_time * png_const_timep;
+typedef png_time * * png_timepp;
+
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+/* png_unknown_chunk is a structure to hold queued chunks for which there is
+ * no specific support. The idea is that we can use this to queue
+ * up private chunks for output even though the library doesn't actually
+ * know about their semantics.
+ *
+ * The data in the structure is set by libpng on read and used on write.
+ */
+typedef struct png_unknown_chunk_t
{
- /* the following are necessary for every PNG file */
- png_uint_32 width; /* width of image in pixels (from IHDR) */
- png_uint_32 height; /* height of image in pixels (from IHDR) */
- png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
- png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
- png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
- png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
- png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
- png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
- png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
- png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
- png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
- png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
-
- /* The following is informational only on read, and not used on writes. */
- png_byte channels; /* number of data channels per pixel (1, 3, 4)*/
- png_byte pixel_depth; /* number of bits per pixel */
- png_byte spare_byte; /* to align the data, and for future use */
- png_byte signature[8]; /* magic bytes read by libpng from start of file */
-
- /* The rest of the data is optional. If you are reading, check the
- * valid field to see if the information in these are valid. If you
- * are writing, set the valid field to those chunks you want written,
- * and initialize the appropriate fields below.
- */
+ png_byte name[5]; /* Textual chunk name with '\0' terminator */
+ png_byte *data; /* Data, should not be modified on read! */
+ png_size_t size;
+
+ /* On write 'location' must be set using the flag values listed below.
+ * Notice that on read it is set by libpng however the values stored have
+ * more bits set than are listed below. Always treat the value as a
+ * bitmask. On write set only one bit - setting multiple bits may cause the
+ * chunk to be written in multiple places.
+ */
+ png_byte location; /* mode of operation at read time */
+}
+png_unknown_chunk;
-#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED) || \
- defined(PNG_READ_GAMMA_SUPPORTED)
- /* The gAMA chunk describes the gamma characteristics of the system
- * on which the image was created, normally in the range [1.0, 2.5].
- * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
- */
- float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
-#endif /* PNG_READ_gAMA_SUPPORTED || PNG_WRITE_gAMA_SUPPORTED */
-
-#if defined(PNG_READ_sRGB_SUPPORTED) || defined(PNG_WRITE_sRGB_SUPPORTED)
- /* GR-P, 0.96a */
- /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
- png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
-#endif /* PNG_READ_sRGB_SUPPORTED || PNG_WRITE_sRGB_SUPPORTED */
-
-#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
- defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
- /* The tEXt and zTXt chunks contain human-readable textual data in
- * uncompressed and compressed forms, respectively. The data in "text"
- * is an array of pointers to uncompressed, null-terminated C strings.
- * Each chunk has a keyword that describes the textual data contained
- * in that chunk. Keywords are not required to be unique, and the text
- * string may be empty. Any number of text chunks may be in an image.
- */
- int num_text; /* number of comments read/to write */
- int max_text; /* current size of text array */
- png_textp text; /* array of comments read/to write */
-#endif /* PNG_READ_OR_WRITE_tEXt_OR_zTXt_SUPPORTED */
-#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
- /* The tIME chunk holds the last time the displayed image data was
- * modified. See the png_time struct for the contents of this struct.
- */
- png_time mod_time;
-#endif /* PNG_READ_tIME_SUPPORTED || PNG_WRITE_tIME_SUPPORTED */
-#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
- /* The sBIT chunk specifies the number of significant high-order bits
- * in the pixel data. Values are in the range [1, bit_depth], and are
- * only specified for the channels in the pixel data. The contents of
- * the low-order bits is not specified. Data is valid if
- * (valid & PNG_INFO_sBIT) is non-zero.
- */
- png_color_8 sig_bit; /* significant bits in color channels */
-#endif /* PNG_READ_sBIT_SUPPORTED || PNG_WRITE_sBIT_SUPPORTED */
-#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED) || \
- defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
- /* The tRNS chunk supplies transparency data for paletted images and
- * other image types that don't need a full alpha channel. There are
- * "num_trans" transparency values for a paletted image, stored in the
- * same order as the palette colors, starting from index 0. Values
- * for the data are in the range [0, 255], ranging from fully transparent
- * to fully opaque, respectively. For non-paletted images, there is a
- * single color specified that should be treated as fully transparent.
- * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
- */
- png_bytep trans; /* transparent values for paletted image */
- png_color_16 trans_values; /* transparent color for non-palette image */
-#endif /* PNG_READ_tRNS_SUPPORTED || PNG_WRITE_tRNS_SUPPORTED */
-#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED) || \
- defined(PNG_READ_BACKGROUND_SUPPORTED)
- /* The bKGD chunk gives the suggested image background color if the
- * display program does not have its own background color and the image
- * is needs to composited onto a background before display. The colors
- * in "background" are normally in the same color space/depth as the
- * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
- */
- png_color_16 background;
-#endif /* PNG_READ_bKGD_SUPPORTED || PNG_WRITE_bKGD_SUPPORTED */
-#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
- /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
- * and downwards from the top-left corner of the display, page, or other
- * application-specific co-ordinate space. See the PNG_OFFSET_ defines
- * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
- */
- png_uint_32 x_offset; /* x offset on page */
- png_uint_32 y_offset; /* y offset on page */
- png_byte offset_unit_type; /* offset units type */
-#endif /* PNG_READ_oFFs_SUPPORTED || PNG_WRITE_oFFs_SUPPORTED */
-#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
- /* The pHYs chunk gives the physical pixel density of the image for
- * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
- * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
- */
- png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
- png_uint_32 y_pixels_per_unit; /* vertical pixel density */
- png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
-#endif /* PNG_READ_pHYs_SUPPORTED || PNG_WRITE_pHYs_SUPPORTED */
-#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
- /* The hIST chunk contains the relative frequency or importance of the
- * various palette entries, so that a viewer can intelligently select a
- * reduced-color palette, if required. Data is an array of "num_palette"
- * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
- * is non-zero.
- */
- png_uint_16p hist;
-#endif /* PNG_READ_hIST_SUPPORTED || PNG_WRITE_hIST_SUPPORTED */
-#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
- /* The cHRM chunk describes the CIE color characteristics of the monitor
- * on which the PNG was created. This data allows the viewer to do gamut
- * mapping of the input image to ensure that the viewer sees the same
- * colors in the image as the creator. Values are in the range
- * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
- */
- float x_white;
- float y_white;
- float x_red;
- float y_red;
- float x_green;
- float y_green;
- float x_blue;
- float y_blue;
-#endif /* PNG_READ_cHRM_SUPPORTED || PNG_WRITE_cHRM_SUPPORTED */
-#if defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED)
- /* The pCAL chunk describes a transformation between the stored pixel
- * values and original physcical data values used to create the image.
- * The integer range [0, 2^bit_depth - 1] maps to the floating-point
- * range given by [pcal_X0, pcal_X1], and are further transformed by a
- * (possibly non-linear) transformation function given by "pcal_type"
- * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
- * defines below, and the PNG-Group's Scientific Visualization extension
- * chunks document png-scivis-19970203 for a complete description of the
- * transformations and how they should be implemented, as well as the
- * png-extensions document for a description of the ASCII parameter
- * strings. Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
- */
- png_charp pcal_purpose; /* pCAL chunk description string */
- png_int_32 pcal_X0; /* minimum value */
- png_int_32 pcal_X1; /* maximum value */
- png_charp pcal_units; /* Latin-1 string giving physical units */
- png_charpp pcal_params; /* ASCII strings containing parameter values */
- png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
- png_byte pcal_nparams; /* number of parameters given in pcal_params */
-#endif /* PNG_READ_pCAL_SUPPORTED || PNG_WRITE_pCAL_SUPPORTED */
-} png_info;
-typedef png_info FAR * png_infop;
-typedef png_info FAR * FAR * png_infopp;
+typedef png_unknown_chunk * png_unknown_chunkp;
+typedef const png_unknown_chunk * png_const_unknown_chunkp;
+typedef png_unknown_chunk * * png_unknown_chunkpp;
+#endif
+
+/* Flag values for the unknown chunk location byte. */
+#define PNG_HAVE_IHDR 0x01
+#define PNG_HAVE_PLTE 0x02
+#define PNG_AFTER_IDAT 0x08
+
+/* Maximum positive integer used in PNG is (2^31)-1 */
+#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
+#define PNG_UINT_32_MAX ((png_uint_32)(-1))
+#define PNG_SIZE_MAX ((png_size_t)(-1))
+
+/* These are constants for fixed point values encoded in the
+ * PNG specification manner (x100000)
+ */
+#define PNG_FP_1 100000
+#define PNG_FP_HALF 50000
+#define PNG_FP_MAX ((png_fixed_point)0x7fffffffL)
+#define PNG_FP_MIN (-PNG_FP_MAX)
/* These describe the color_type field in png_info. */
/* color type masks */
#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
+/* aliases */
+#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
+#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
-/* This is for compression type. PNG 1.0 only defines the single type. */
+/* This is for compression type. PNG 1.0-1.2 only define the single type. */
#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
-/* This is for filter type. PNG 1.0 only defines the single type. */
+/* This is for filter type. PNG 1.0-1.2 only define the single type. */
#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
+#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
/* These are for the interlacing type. These values should NOT be changed. */
#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
#define PNG_EQUATION_LAST 4 /* Not a valid value */
+/* These are for the sCAL chunk. These values should NOT be changed. */
+#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
+#define PNG_SCALE_METER 1 /* meters per pixel */
+#define PNG_SCALE_RADIAN 2 /* radians per pixel */
+#define PNG_SCALE_LAST 3 /* Not a valid value */
+
/* These are for the pHYs chunk. These values should NOT be changed. */
#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
#define PNG_RESOLUTION_METER 1 /* pixels/meter */
#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
/* These are for the sRGB chunk. These values should NOT be changed. */
-#define PNG_sRGB_INTENT_SATURATION 0
-#define PNG_sRGB_INTENT_PERCEPTUAL 1
-#define PNG_sRGB_INTENT_ABSOLUTE 2
-#define PNG_sRGB_INTENT_RELATIVE 3
+#define PNG_sRGB_INTENT_PERCEPTUAL 0
+#define PNG_sRGB_INTENT_RELATIVE 1
+#define PNG_sRGB_INTENT_SATURATION 2
+#define PNG_sRGB_INTENT_ABSOLUTE 3
#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
+/* This is for text chunks */
+#define PNG_KEYWORD_MAX_LENGTH 79
+/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
+#define PNG_MAX_PALETTE_LENGTH 256
/* These determine if an ancillary chunk's data has been successfully read
* from the PNG header, or if the application has filled in the corresponding
#define PNG_INFO_tIME 0x0200
#define PNG_INFO_pCAL 0x0400
#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
+#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
+#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
+#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
+#define PNG_INFO_IDAT 0x8000 /* ESR, 1.0.6 */
/* This is used for the transformation routines, as some of them
* change these values for the row. It also should enable using
*/
typedef struct png_row_info_struct
{
- png_uint_32 width; /* width of row */
- png_uint_32 rowbytes; /* number of bytes in row */
- png_byte color_type; /* color type of row */
- png_byte bit_depth; /* bit depth of row */
- png_byte channels; /* number of channels (1, 2, 3, or 4) */
+ png_uint_32 width; /* width of row */
+ png_size_t rowbytes; /* number of bytes in row */
+ png_byte color_type; /* color type of row */
+ png_byte bit_depth; /* bit depth of row */
+ png_byte channels; /* number of channels (1, 2, 3, or 4) */
png_byte pixel_depth; /* bits per pixel (depth * channels) */
} png_row_info;
-typedef png_row_info FAR * png_row_infop;
-typedef png_row_info FAR * FAR * png_row_infopp;
+typedef png_row_info * png_row_infop;
+typedef png_row_info * * png_row_infopp;
/* These are the function types for the I/O functions and for the functions
* that allow the user to override the default I/O functions with his or her
* own. The png_error_ptr type should match that of user-supplied warning
* and error functions, while the png_rw_ptr type should match that of the
- * user read/write data functions.
+ * user read/write data functions. Note that the 'write' function must not
+ * modify the buffer it is passed. The 'read' function, on the other hand, is
+ * expected to return the read data in the buffer.
*/
-typedef struct png_struct_def png_struct;
-typedef png_struct FAR * png_structp;
+typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp));
+typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t));
+typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp));
+typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32,
+ int));
+typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32,
+ int));
-typedef void (*png_error_ptr) PNGARG((png_structp, png_const_charp));
-typedef void (*png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
-typedef void (*png_flush_ptr) PNGARG((png_structp));
-typedef void (*png_read_status_ptr) PNGARG((png_structp, png_uint_32, int));
-typedef void (*png_write_status_ptr) PNGARG((png_structp, png_uint_32, int));
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-typedef void (*png_progressive_info_ptr) PNGARG((png_structp, png_infop));
-typedef void (*png_progressive_end_ptr) PNGARG((png_structp, png_infop));
-typedef void (*png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
- png_uint_32, int));
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));
+typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));
+
+/* The following callback receives png_uint_32 row_number, int pass for the
+ * png_bytep data of the row. When transforming an interlaced image the
+ * row number is the row number within the sub-image of the interlace pass, so
+ * the value will increase to the height of the sub-image (not the full image)
+ * then reset to 0 for the next pass.
+ *
+ * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+ * find the output pixel (x,y) given an interlaced sub-image pixel
+ * (row,col,pass). (See below for these macros.)
+ */
+typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,
+ png_uint_32, int));
+#endif
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-typedef void (*png_user_transform_ptr) PNGARG((png_structp,
- png_row_infop, png_bytep));
-#endif /* PNG_READ|WRITE_USER_TRANSFORM_SUPPORTED */
+typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop,
+ png_bytep));
+#endif
-typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
-typedef void (*png_free_ptr) PNGARG((png_structp, png_structp));
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
+ png_unknown_chunkp));
+#endif
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
+/* not used anywhere */
+/* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); */
+#endif
-/* The structure that holds the information to read and write PNG files.
- * The only people who need to care about what is inside of this are the
- * people who will be modifying the library for their own special needs.
- * It should NOT be accessed directly by an application, except to store
- * the jmp_buf.
+#ifdef PNG_SETJMP_SUPPORTED
+/* This must match the function definition in <setjmp.h>, and the application
+ * must include this before png.h to obtain the definition of jmp_buf. The
+ * function is required to be PNG_NORETURN, but this is not checked. If the
+ * function does return the application will crash via an abort() or similar
+ * system level call.
+ *
+ * If you get a warning here while building the library you may need to make
+ * changes to ensure that pnglibconf.h records the calling convention used by
+ * your compiler. This may be very difficult - try using a different compiler
+ * to build the library!
*/
+PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);
+#endif
+
+/* Transform masks for the high-level interface */
+#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
+#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
+#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
+#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
+#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
+#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
+#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
+#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
+#define PNG_TRANSFORM_BGR 0x0080 /* read and write */
+#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
+#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
+#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
+#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */
+/* Added to libpng-1.2.34 */
+#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
+#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
+/* Added to libpng-1.4.0 */
+#define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */
+/* Added to libpng-1.5.4 */
+#define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */
+#define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */
+
+/* Flags for MNG supported features */
+#define PNG_FLAG_MNG_EMPTY_PLTE 0x01
+#define PNG_FLAG_MNG_FILTER_64 0x04
+#define PNG_ALL_MNG_FEATURES 0x05
+
+/* NOTE: prior to 1.5 these functions had no 'API' style declaration,
+ * this allowed the zlib default functions to be used on Windows
+ * platforms. In 1.5 the zlib default malloc (which just calls malloc and
+ * ignores the first argument) should be completely compatible with the
+ * following.
+ */
+typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp,
+ png_alloc_size_t));
+typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp));
-struct png_struct_def
-{
- jmp_buf jmpbuf; /* used in png_error */
-
- png_error_ptr error_fn; /* function for printing errors and aborting */
- png_error_ptr warning_fn; /* function for printing warnings */
- png_voidp error_ptr; /* user supplied struct for error functions */
- png_rw_ptr write_data_fn; /* function for writing output data */
- png_rw_ptr read_data_fn; /* function for reading input data */
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
- defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
- png_user_transform_ptr read_user_transform_fn; /* user read transform */
- png_user_transform_ptr write_user_transform_fn; /* user write transform */
-#endif
- png_voidp io_ptr; /* ptr to application struct for I/O functions*/
-
- png_uint_32 mode; /* tells us where we are in the PNG file */
- png_uint_32 flags; /* flags indicating various things to libpng */
- png_uint_32 transformations; /* which transformations to perform */
-
- z_stream zstream; /* pointer to decompression structure (below) */
- png_bytep zbuf; /* buffer for zlib */
- png_size_t zbuf_size; /* size of zbuf */
- int zlib_level; /* holds zlib compression level */
- int zlib_method; /* holds zlib compression method */
- int zlib_window_bits; /* holds zlib compression window bits */
- int zlib_mem_level; /* holds zlib compression memory level */
- int zlib_strategy; /* holds zlib compression strategy */
-
- png_uint_32 width; /* width of image in pixels */
- png_uint_32 height; /* height of image in pixels */
- png_uint_32 num_rows; /* number of rows in current pass */
- png_uint_32 usr_width; /* width of row at start of write */
- png_uint_32 rowbytes; /* size of row in bytes */
- png_uint_32 irowbytes; /* size of current interlaced row in bytes */
- png_uint_32 iwidth; /* width of current interlaced row in pixels */
- png_uint_32 row_number; /* current row in interlace pass */
- png_bytep prev_row; /* buffer to save previous (unfiltered) row */
- png_bytep row_buf; /* buffer to save current (unfiltered) row */
- png_bytep sub_row; /* buffer to save "sub" row when filtering */
- png_bytep up_row; /* buffer to save "up" row when filtering */
- png_bytep avg_row; /* buffer to save "avg" row when filtering */
- png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
- png_row_info row_info; /* used for transformation routines */
-
- png_uint_32 idat_size; /* current IDAT size for read */
- png_uint_32 crc; /* current chunk CRC value */
- png_colorp palette; /* palette from the input file */
- png_uint_16 num_palette; /* number of color entries in palette */
- png_uint_16 num_trans; /* number of transparency values */
- png_byte chunk_name[5]; /* null-terminated name of current chunk */
- png_byte compression; /* file compression type (always 0) */
- png_byte filter; /* file filter type (always 0) */
- png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
- png_byte pass; /* current interlace pass (0 - 6) */
- png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
- png_byte color_type; /* color type of file */
- png_byte bit_depth; /* bit depth of file */
- png_byte usr_bit_depth; /* bit depth of users row */
- png_byte pixel_depth; /* number of bits per pixel */
- png_byte channels; /* number of channels in file */
- png_byte usr_channels; /* channels at start of write */
- png_byte sig_bytes; /* magic bytes read/written from start of file */
-
-#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
- png_uint_16 filler; /* filler bytes for pixel expansion */
-#endif /* PNG_READ_FILLER_SUPPORTED */
-#if defined(PNG_READ_bKGD_SUPPORTED)
- png_byte background_gamma_type;
- float background_gamma;
- png_color_16 background; /* background color in screen gamma space */
-#if defined(PNG_READ_GAMMA_SUPPORTED)
- png_color_16 background_1; /* background normalized to gamma 1.0 */
-#endif /* PNG_READ_GAMMA && PNG_READ_bKGD_SUPPORTED */
-#endif /* PNG_READ_bKGD_SUPPORTED */
-#if defined(PNG_WRITE_FLUSH_SUPPORTED)
- png_flush_ptr output_flush_fn;/* Function for flushing output */
- png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
- png_uint_32 flush_rows; /* number of rows written since last flush */
-#endif /* PNG_WRITE_FLUSH_SUPPORTED */
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
- int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
- float gamma; /* file gamma value */
- float screen_gamma; /* screen gamma value (display_gamma/viewing_gamma */
-#endif /* PNG_READ_GAMMA_SUPPORTED */
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
- png_bytep gamma_table; /* gamma table for 8 bit depth files */
- png_bytep gamma_from_1; /* converts from 1.0 to screen */
- png_bytep gamma_to_1; /* converts from file to 1.0 */
- png_uint_16pp gamma_16_table; /* gamma table for 16 bit depth files */
- png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
- png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
-#endif /* PNG_READ_GAMMA_SUPPORTED || PNG_WRITE_GAMMA_SUPPORTED */
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined (PNG_READ_sBIT_SUPPORTED)
- png_color_8 sig_bit; /* significant bits in each available channel */
-#endif /* PNG_READ_GAMMA_SUPPORTED || PNG_READ_sBIT_SUPPORTED */
-#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
- png_color_8 shift; /* shift for significant bit tranformation */
-#endif /* PNG_READ_SHIFT_SUPPORTED || PNG_WRITE_SHIFT_SUPPORTED */
-#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
- || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
- png_bytep trans; /* transparency values for paletted files */
- png_color_16 trans_values; /* transparency values for non-paletted files */
-#endif /* PNG_READ|WRITE_tRNS_SUPPORTED||PNG_READ_EXPAND|BACKGROUND_SUPPORTED */
- png_read_status_ptr read_row_fn; /* called after each row is decoded */
- png_write_status_ptr write_row_fn; /* called after each row is encoded */
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
- png_progressive_info_ptr info_fn; /* called after header data fully read */
- png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
- png_progressive_end_ptr end_fn; /* called after image is complete */
- png_bytep save_buffer_ptr; /* current location in save_buffer */
- png_bytep save_buffer; /* buffer for previously read data */
- png_bytep current_buffer_ptr; /* current location in current_buffer */
- png_bytep current_buffer; /* buffer for recently used data */
- png_uint_32 push_length; /* size of current input chunk */
- png_uint_32 skip_length; /* bytes to skip in input data */
- png_size_t save_buffer_size; /* amount of data now in save_buffer */
- png_size_t save_buffer_max; /* total size of save_buffer */
- png_size_t buffer_size; /* total amount of available input data */
- png_size_t current_buffer_size; /* amount of data now in current_buffer */
- int process_mode; /* what push library is currently doing */
- int cur_palette; /* current push library palette index */
-#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
- png_size_t current_text_size; /* current size of text input data */
- png_size_t current_text_left; /* how much text left to read in input */
- png_charp current_text; /* current text chunk buffer */
- png_charp current_text_ptr; /* current location in current_text */
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_READ_tEXt/zTXt_SUPPORTED */
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
-/* for the Borland special 64K segment handler */
- png_bytepp offset_table_ptr;
- png_bytep offset_table;
- png_uint_16 offset_table_number;
- png_uint_16 offset_table_count;
- png_uint_16 offset_table_count_free;
-#endif /* __TURBOC__&&!_Windows&&!__FLAT__ */
-#if defined(PNG_READ_DITHER_SUPPORTED)
- png_bytep palette_lookup; /* lookup table for dithering */
- png_bytep dither_index; /* index translation for palette files */
-#endif /* PNG_READ_DITHER_SUPPORTED */
-#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_READ_hIST_SUPPORTED)
- png_uint_16p hist; /* histogram */
-#endif
-#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
- png_byte heuristic_method; /* heuristic for row filter selection */
- png_byte num_prev_filters; /* number of weights for previous rows */
- png_bytep prev_filters; /* filter type(s) of previous row(s) */
- png_uint_16p filter_weights; /* weight(s) for previous line(s) */
- png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
- png_uint_16p filter_costs; /* relative filter calculation cost */
- png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
-#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
-#if defined(PNG_TIME_RFC1123_SUPPORTED)
- png_charp time_buffer; /* String to hold RFC 1123 time text */
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
-#ifdef PNG_USER_MEM_SUPPORTED
- png_voidp mem_ptr; /* user supplied struct for mem functions */
- png_malloc_ptr malloc_fn; /* function for allocating memory */
- png_free_ptr free_fn; /* function for freeing memory */
-#endif /* PNG_USER_MEM_SUPPORTED */
-#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
- png_byte rgb_to_gray_status;
- png_byte rgb_to_gray_red_coeff;
- png_byte rgb_to_gray_green_coeff;
- png_byte rgb_to_gray_blue_coeff;
-#endif
-};
-
-typedef png_struct FAR * FAR * png_structpp;
-
-/* Here are the function definitions most commonly used. This is not
- * the place to find out how to use libpng. See libpng.txt for the
+/* Section 3: exported functions
+ * Here are the function definitions most commonly used. This is not
+ * the place to find out how to use libpng. See libpng-manual.txt for the
* full explanation, see example.c for the summary. This just provides
- * a simple one line of the use of each function.
+ * a simple one line description of the use of each function.
+ *
+ * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in
+ * pngconf.h and in the *.dfn files in the scripts directory.
+ *
+ * PNG_EXPORT(ordinal, type, name, (args));
+ *
+ * ordinal: ordinal that is used while building
+ * *.def files. The ordinal value is only
+ * relevant when preprocessing png.h with
+ * the *.dfn files for building symbol table
+ * entries, and are removed by pngconf.h.
+ * type: return type of the function
+ * name: function name
+ * args: function arguments, with types
+ *
+ * When we wish to append attributes to a function prototype we use
+ * the PNG_EXPORTA() macro instead.
+ *
+ * PNG_EXPORTA(ordinal, type, name, (args), attributes);
+ *
+ * ordinal, type, name, and args: same as in PNG_EXPORT().
+ * attributes: function attributes
*/
+/* Returns the version number of the library */
+PNG_EXPORT(1, png_uint_32, png_access_version_number, (void));
+
/* Tell lib we have already handled the first <num_bytes> magic bytes.
* Handling more than 8 bytes from the beginning of the file is an error.
*/
-extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
- int num_bytes));
+PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes));
/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
* PNG file. Returns zero if the supplied bytes match the 8-byte PNG
* signature, and non-zero otherwise. Having num_to_check == 0 or
* start > 7 will always fail (ie return non-zero).
*/
-extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
- png_size_t num_to_check));
+PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start,
+ png_size_t num_to_check));
/* Simple signature checking function. This is the same as calling
* png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
*/
-extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
+#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n))
/* Allocate and initialize png_ptr struct for reading, and any other memory. */
-extern PNG_EXPORT(png_structp,png_create_read_struct)
- PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
- png_error_ptr error_fn, png_error_ptr warn_fn));
+PNG_EXPORTA(4, png_structp, png_create_read_struct,
+ (png_const_charp user_png_ver, png_voidp error_ptr,
+ png_error_ptr error_fn, png_error_ptr warn_fn),
+ PNG_ALLOCATED);
/* Allocate and initialize png_ptr struct for writing, and any other memory */
-extern PNG_EXPORT(png_structp,png_create_write_struct)
- PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
- png_error_ptr error_fn, png_error_ptr warn_fn));
+PNG_EXPORTA(5, png_structp, png_create_write_struct,
+ (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
+ png_error_ptr warn_fn),
+ PNG_ALLOCATED);
+
+PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size,
+ (png_const_structrp png_ptr));
+
+PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr,
+ png_size_t size));
+
+/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp
+ * match up.
+ */
+#ifdef PNG_SETJMP_SUPPORTED
+/* This function returns the jmp_buf built in to *png_ptr. It must be
+ * supplied with an appropriate 'longjmp' function to use on that jmp_buf
+ * unless the default error function is overridden in which case NULL is
+ * acceptable. The size of the jmp_buf is checked against the actual size
+ * allocated by the library - the call will return NULL on a mismatch
+ * indicating an ABI mismatch.
+ */
+PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr,
+ png_longjmp_ptr longjmp_fn, size_t jmp_buf_size));
+# define png_jmpbuf(png_ptr) \
+ (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf))))
+#else
+# define png_jmpbuf(png_ptr) \
+ (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
+#endif
+/* This function should be used by libpng applications in place of
+ * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it
+ * will use it; otherwise it will call PNG_ABORT(). This function was
+ * added in libpng-1.5.0.
+ */
+PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val),
+ PNG_NORETURN);
+
+#ifdef PNG_READ_SUPPORTED
+/* Reset the compression stream */
+PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED);
+#endif
+/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
#ifdef PNG_USER_MEM_SUPPORTED
-extern PNG_EXPORT(png_structp,png_create_read_struct_2)
- PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
- png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
- png_malloc_ptr malloc_fn, png_free_ptr free_fn));
-extern PNG_EXPORT(png_structp,png_create_write_struct_2)
- PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
- png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
- png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+PNG_EXPORTA(11, png_structp, png_create_read_struct_2,
+ (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
+ png_error_ptr warn_fn,
+ png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
+ PNG_ALLOCATED);
+PNG_EXPORTA(12, png_structp, png_create_write_struct_2,
+ (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
+ png_error_ptr warn_fn,
+ png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
+ PNG_ALLOCATED);
#endif
+/* Write the PNG file signature. */
+PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr));
+
/* Write a PNG chunk - size, type, (optional) data, CRC. */
-extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
- png_bytep chunk_name, png_bytep data, png_size_t length));
+PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep
+ chunk_name, png_const_bytep data, png_size_t length));
/* Write the start of a PNG chunk - length and chunk name. */
-extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
- png_bytep chunk_name, png_uint_32 length));
+PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr,
+ png_const_bytep chunk_name, png_uint_32 length));
/* Write the data of a PNG chunk started with png_write_chunk_start(). */
-extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
- png_bytep data, png_size_t length));
+PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr,
+ png_const_bytep data, png_size_t length));
/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
-extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
+PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr));
/* Allocate and initialize the info structure */
-extern PNG_EXPORT(png_infop,png_create_info_struct)
- PNGARG((png_structp png_ptr));
+PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr),
+ PNG_ALLOCATED);
-/* Initialize the info structure (old interface - NOT DLL EXPORTED) */
-extern void png_info_init PNGARG((png_infop info_ptr));
+/* DEPRECATED: this function allowed init structures to be created using the
+ * default allocation method (typically malloc). Use is deprecated in 1.6.0 and
+ * the API will be removed in the future.
+ */
+PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr,
+ png_size_t png_info_struct_size), PNG_DEPRECATED);
/* Writes all the PNG information before the image. */
-extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
- png_infop info_ptr));
+PNG_EXPORT(20, void, png_write_info_before_PLTE,
+ (png_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(21, void, png_write_info,
+ (png_structrp png_ptr, png_const_inforp info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the information before the actual image data. */
+PNG_EXPORT(22, void, png_read_info,
+ (png_structrp png_ptr, png_inforp info_ptr));
+#endif
-/* read the information before the actual image data. */
-extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
- png_infop info_ptr));
+#ifdef PNG_TIME_RFC1123_SUPPORTED
+ /* Convert to a US string format: there is no localization support in this
+ * routine. The original implementation used a 29 character buffer in
+ * png_struct, this will be removed in future versions.
+ */
+#if PNG_LIBPNG_VER < 10700
+/* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */
+PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr,
+ png_const_timep ptime),PNG_DEPRECATED);
+#endif
+PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29],
+ png_const_timep ptime));
+#endif
-#if defined(PNG_TIME_RFC1123_SUPPORTED)
-extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
- PNGARG((png_structp png_ptr, png_timep ptime));
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#ifdef PNG_CONVERT_tIME_SUPPORTED
+/* Convert from a struct tm to png_time */
+PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,
+ const struct tm * ttime));
-#if defined(PNG_WRITE_tIME_SUPPORTED)
-/* convert from a struct tm to png_time */
-extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
- struct tm FAR * ttime));
+/* Convert from time_t to png_time. Uses gmtime() */
+PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime));
+#endif /* PNG_CONVERT_tIME_SUPPORTED */
-/* convert from time_t to png_time. Uses gmtime() */
-extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
- time_t ttime));
-#endif /* PNG_WRITE_tIME_SUPPORTED */
+#ifdef PNG_READ_EXPAND_SUPPORTED
+/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
+PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr));
+PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr));
+PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr));
+PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr));
+#endif
-#if defined(PNG_READ_EXPAND_SUPPORTED)
-/* Expand data to 24 bit RGB, or 8 bit grayscale, with alpha if available. */
-extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_EXPAND_SUPPORTED */
+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion
+ * of a tRNS chunk if present.
+ */
+PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr));
+#endif
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* Use blue, green, red order for pixels. */
-extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_BGR_SUPPORTED || PNG_WRITE_BGR_SUPPORTED */
+PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr));
+#endif
-#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
-/* Expand the grayscale to 24 bit RGB if necessary. */
-extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_GRAY_TO_RGB_SUPPORTED */
+#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
+/* Expand the grayscale to 24-bit RGB if necessary. */
+PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr));
+#endif
-#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
/* Reduce RGB to grayscale. */
-extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
- int error_action, float red, float green ));
-extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
- png_ptr));
-#endif /* PNG_READ_RGB_TO_GRAY_SUPPORTED */
-
-extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
- png_colorp palette));
-
-#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_STRIP_ALPHA_SUPPORTED */
-
-#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
- defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_SWAP_ALPHA_SUPPORTED || PNG_WRITE_SWAP_ALPHA_SUPPORTED */
-
-#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
- defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_INVERT_ALPHA_SUPPORTED || PNG_WRITE_INVERT_ALPHA_SUPPORTED */
-
-#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
-/* Add a filler byte to 24-bit RGB images. */
-extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
- png_uint_32 filler, int flags));
-
-/* The values of the PNG_FILLER_ defines should NOT be changed */
-#define PNG_FILLER_BEFORE 0
-#define PNG_FILLER_AFTER 1
-#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
-
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* Swap bytes in 16 bit depth files. */
-extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_SWAP_SUPPORTED || PNG_WRITE_SWAP_SUPPORTED */
-
-#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-/* Use 1 byte per pixel in 1, 2, or 4 bit depth files. */
-extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_PACK_SUPPORTED || PNG_WRITE_PACK_SUPPORTED */
+#define PNG_ERROR_ACTION_NONE 1
+#define PNG_ERROR_ACTION_WARN 2
+#define PNG_ERROR_ACTION_ERROR 3
+#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/
-#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-/* Swap packing order of pixels in bytes. */
-extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_PACKSWAP_SUPPORTED || PNG_WRITE_PACKSWAP_SUPPOR */
+PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr,
+ int error_action, double red, double green))
+PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr,
+ int error_action, png_fixed_point red, png_fixed_point green))
-#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
-/* Converts files to legal bit depths. */
-extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
- png_color_8p true_bits));
-#endif /* PNG_READ_SHIFT_SUPPORTED || PNG_WRITE_SHIFT_SUPPORTED */
+PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp
+ png_ptr));
+#endif
-#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
- defined(PNG_WRITE_INTERLACING_SUPPORTED)
-/* Have the code handle the interlacing. Returns the number of passes. */
-extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_INTERLACING_SUPPORTED || PNG_WRITE_INTERLACING_SUPPORTED */
+#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
+PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
+ png_colorp palette));
+#endif
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-/* Invert monocrome files */
-extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_INVERT_SUPPORTED || PNG_WRITE_INVERT_SUPPORTED */
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED)
-/* Handle alpha and tRNS by replacing with a background color. */
-extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
- png_color_16p background_color, int background_gamma_code,
- int need_expand, double background_gamma));
-#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
-#define PNG_BACKGROUND_GAMMA_SCREEN 1
-#define PNG_BACKGROUND_GAMMA_FILE 2
-#define PNG_BACKGROUND_GAMMA_UNIQUE 3
-#endif /* PNG_READ_BACKGROUND_SUPPORTED */
-
-#if defined(PNG_READ_16_TO_8_SUPPORTED)
-/* strip the second byte of information from a 16 bit depth file. */
-extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_16_TO_8_SUPPORTED */
-
-#if defined(PNG_READ_DITHER_SUPPORTED)
-/* Turn on dithering, and reduce the palette to the number of colors available. */
-extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
- png_colorp palette, int num_palette, int maximum_colors,
- png_uint_16p histogram, int full_dither));
-#endif /* PNG_READ_DITHER_SUPPORTED */
-
-#if defined(PNG_READ_GAMMA_SUPPORTED)
-/* Handle gamma correction. Screen_gamma=(display_gamma/viewing_gamma) */
-extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
- double screen_gamma, double default_file_gamma));
-#endif /* PNG_READ_GAMMA_SUPPORTED */
-
-#if defined(PNG_WRITE_FLUSH_SUPPORTED)
-/* Set how many lines between output flushes - 0 for no flushing */
-extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+/* How the alpha channel is interpreted - this affects how the color channels of
+ * a PNG file are returned when an alpha channel, or tRNS chunk in a palette
+ * file, is present.
+ *
+ * This has no effect on the way pixels are written into a PNG output
+ * datastream. The color samples in a PNG datastream are never premultiplied
+ * with the alpha samples.
+ *
+ * The default is to return data according to the PNG specification: the alpha
+ * channel is a linear measure of the contribution of the pixel to the
+ * corresponding composited pixel. The gamma encoded color channels must be
+ * scaled according to the contribution and to do this it is necessary to undo
+ * the encoding, scale the color values, perform the composition and reencode
+ * the values. This is the 'PNG' mode.
+ *
+ * The alternative is to 'associate' the alpha with the color information by
+ * storing color channel values that have been scaled by the alpha. The
+ * advantage is that the color channels can be resampled (the image can be
+ * scaled) in this form. The disadvantage is that normal practice is to store
+ * linear, not (gamma) encoded, values and this requires 16-bit channels for
+ * still images rather than the 8-bit channels that are just about sufficient if
+ * gamma encoding is used. In addition all non-transparent pixel values,
+ * including completely opaque ones, must be gamma encoded to produce the final
+ * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the
+ * latter being the two common names for associated alpha color channels.)
+ *
+ * Since it is not necessary to perform arithmetic on opaque color values so
+ * long as they are not to be resampled and are in the final color space it is
+ * possible to optimize the handling of alpha by storing the opaque pixels in
+ * the PNG format (adjusted for the output color space) while storing partially
+ * opaque pixels in the standard, linear, format. The accuracy required for
+ * standard alpha composition is relatively low, because the pixels are
+ * isolated, therefore typically the accuracy loss in storing 8-bit linear
+ * values is acceptable. (This is not true if the alpha channel is used to
+ * simulate transparency over large areas - use 16 bits or the PNG mode in
+ * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is
+ * treated as opaque only if the alpha value is equal to the maximum value.
+ *
+ * The final choice is to gamma encode the alpha channel as well. This is
+ * broken because, in practice, no implementation that uses this choice
+ * correctly undoes the encoding before handling alpha composition. Use this
+ * choice only if other serious errors in the software or hardware you use
+ * mandate it; the typical serious error is for dark halos to appear around
+ * opaque areas of the composited PNG image because of arithmetic overflow.
+ *
+ * The API function png_set_alpha_mode specifies which of these choices to use
+ * with an enumerated 'mode' value and the gamma of the required output:
+ */
+#define PNG_ALPHA_PNG 0 /* according to the PNG standard */
+#define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */
+#define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */
+#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */
+#define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */
+#define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */
+
+PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode,
+ double output_gamma))
+PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr,
+ int mode, png_fixed_point output_gamma))
+#endif
+
+#if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
+/* The output_gamma value is a screen gamma in libpng terminology: it expresses
+ * how to decode the output values, not how they are encoded. The values used
+ * correspond to the normal numbers used to describe the overall gamma of a
+ * computer display system; for example 2.2 for an sRGB conformant system. The
+ * values are scaled by 100000 in the _fixed version of the API (so 220000 for
+ * sRGB.)
+ *
+ * The inverse of the value is always used to provide a default for the PNG file
+ * encoding if it has no gAMA chunk and if png_set_gamma() has not been called
+ * to override the PNG gamma information.
+ *
+ * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode
+ * opaque pixels however pixels with lower alpha values are not encoded,
+ * regardless of the output gamma setting.
+ *
+ * When the standard Porter Duff handling is requested with mode 1 the output
+ * encoding is set to be linear and the output_gamma value is only relevant
+ * as a default for input data that has no gamma information. The linear output
+ * encoding will be overridden if png_set_gamma() is called - the results may be
+ * highly unexpected!
+ *
+ * The following numbers are derived from the sRGB standard and the research
+ * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of
+ * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing
+ * correction required to take account of any differences in the color
+ * environment of the original scene and the intended display environment; the
+ * value expresses how to *decode* the image for display, not how the original
+ * data was *encoded*.
+ *
+ * sRGB provides a peg for the PNG standard by defining a viewing environment.
+ * sRGB itself, and earlier TV standards, actually use a more complex transform
+ * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is
+ * limited to simple power laws.) By saying that an image for direct display on
+ * an sRGB conformant system should be stored with a gAMA chunk value of 45455
+ * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification
+ * makes it possible to derive values for other display systems and
+ * environments.
+ *
+ * The Mac value is deduced from the sRGB based on an assumption that the actual
+ * extra viewing correction used in early Mac display systems was implemented as
+ * a power 1.45 lookup table.
+ *
+ * Any system where a programmable lookup table is used or where the behavior of
+ * the final display device characteristics can be changed requires system
+ * specific code to obtain the current characteristic. However this can be
+ * difficult and most PNG gamma correction only requires an approximate value.
+ *
+ * By default, if png_set_alpha_mode() is not called, libpng assumes that all
+ * values are unencoded, linear, values and that the output device also has a
+ * linear characteristic. This is only very rarely correct - it is invariably
+ * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the
+ * default if you don't know what the right answer is!
+ *
+ * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS
+ * 10.6) which used a correction table to implement a somewhat lower gamma on an
+ * otherwise sRGB system.
+ *
+ * Both these values are reserved (not simple gamma values) in order to allow
+ * more precise correction internally in the future.
+ *
+ * NOTE: the following values can be passed to either the fixed or floating
+ * point APIs, but the floating point API will also accept floating point
+ * values.
+ */
+#define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */
+#define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */
+#define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */
+#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */
+#endif
-/* Flush the current PNG output buffer */
-extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
-#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+/* The following are examples of calls to png_set_alpha_mode to achieve the
+ * required overall gamma correction and, where necessary, alpha
+ * premultiplication.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ * This is the default libpng handling of the alpha channel - it is not
+ * pre-multiplied into the color components. In addition the call states
+ * that the output is for a sRGB system and causes all PNG files without gAMA
+ * chunks to be assumed to be encoded using sRGB.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ * In this case the output is assumed to be something like an sRGB conformant
+ * display preceeded by a power-law lookup table of power 1.45. This is how
+ * early Mac systems behaved.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);
+ * This is the classic Jim Blinn approach and will work in academic
+ * environments where everything is done by the book. It has the shortcoming
+ * of assuming that input PNG data with no gamma information is linear - this
+ * is unlikely to be correct unless the PNG files where generated locally.
+ * Most of the time the output precision will be so low as to show
+ * significant banding in dark areas of the image.
+ *
+ * png_set_expand_16(pp);
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);
+ * This is a somewhat more realistic Jim Blinn inspired approach. PNG files
+ * are assumed to have the sRGB encoding if not marked with a gamma value and
+ * the output is always 16 bits per component. This permits accurate scaling
+ * and processing of the data. If you know that your input PNG files were
+ * generated locally you might need to replace PNG_DEFAULT_sRGB with the
+ * correct value for your system.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);
+ * If you just need to composite the PNG image onto an existing background
+ * and if you control the code that does this you can use the optimization
+ * setting. In this case you just copy completely opaque pixels to the
+ * output. For pixels that are not completely transparent (you just skip
+ * those) you do the composition math using png_composite or png_composite_16
+ * below then encode the resultant 8-bit or 16-bit values to match the output
+ * encoding.
+ *
+ * Other cases
+ * If neither the PNG nor the standard linear encoding work for you because
+ * of the software or hardware you use then you have a big problem. The PNG
+ * case will probably result in halos around the image. The linear encoding
+ * will probably result in a washed out, too bright, image (it's actually too
+ * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably
+ * substantially reduce the halos. Alternatively try:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);
+ * This option will also reduce the halos, but there will be slight dark
+ * halos round the opaque parts of the image where the background is light.
+ * In the OPTIMIZED mode the halos will be light halos where the background
+ * is dark. Take your pick - the halos are unavoidable unless you can get
+ * your hardware/software fixed! (The OPTIMIZED approach is slightly
+ * faster.)
+ *
+ * When the default gamma of PNG files doesn't match the output gamma.
+ * If you have PNG files with no gamma information png_set_alpha_mode allows
+ * you to provide a default gamma, but it also sets the ouput gamma to the
+ * matching value. If you know your PNG files have a gamma that doesn't
+ * match the output you can take advantage of the fact that
+ * png_set_alpha_mode always sets the output gamma but only sets the PNG
+ * default if it is not already set:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ * The first call sets both the default and the output gamma values, the
+ * second call overrides the output gamma without changing the default. This
+ * is easier than achieving the same effect with png_set_gamma. You must use
+ * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will
+ * fire if more than one call to png_set_alpha_mode and png_set_background is
+ * made in the same read operation, however multiple calls with PNG_ALPHA_PNG
+ * are ignored.
+ */
+
+#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
+PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr));
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
+ defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr));
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
+ defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr));
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
+PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler,
+ int flags));
+/* The values of the PNG_FILLER_ defines should NOT be changed */
+# define PNG_FILLER_BEFORE 0
+# define PNG_FILLER_AFTER 1
+/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
+PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr,
+ png_uint_32 filler, int flags));
+#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
-/* optional update palette with requested transformations */
-extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* Swap bytes in 16-bit depth files. */
+PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr));
+#endif
-/* optional call to update the users info structure */
-extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
- png_infop info_ptr));
+#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
+PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr));
+#endif
-/* read a one or more rows of image data.*/
-extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
- png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
+#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
+ defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+/* Swap packing order of pixels in bytes. */
+PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr));
+#endif
-/* read a row of data.*/
-extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
- png_bytep row,
- png_bytep display_row));
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+/* Converts files to legal bit depths. */
+PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p
+ true_bits));
+#endif
-/* read the whole image into memory at once. */
-extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
- png_bytepp image));
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+ defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* Have the code handle the interlacing. Returns the number of passes.
+ * MUST be called before png_read_update_info or png_start_read_image,
+ * otherwise it will not have the desired effect. Note that it is still
+ * necessary to call png_read_row or png_read_rows png_get_image_height
+ * times for each pass.
+*/
+PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr));
+#endif
-/* write a row of image data */
-extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
- png_bytep row));
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+/* Invert monochrome files */
+PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr));
+#endif
-/* write a few rows of image data */
-extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
- png_bytepp row, png_uint_32 num_rows));
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+/* Handle alpha and tRNS by replacing with a background color. Prior to
+ * libpng-1.5.4 this API must not be called before the PNG file header has been
+ * read. Doing so will result in unexpected behavior and possible warnings or
+ * errors if the PNG file contains a bKGD chunk.
+ */
+PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr,
+ png_const_color_16p background_color, int background_gamma_code,
+ int need_expand, double background_gamma))
+PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr,
+ png_const_color_16p background_color, int background_gamma_code,
+ int need_expand, png_fixed_point background_gamma))
+#endif
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+# define PNG_BACKGROUND_GAMMA_UNKNOWN 0
+# define PNG_BACKGROUND_GAMMA_SCREEN 1
+# define PNG_BACKGROUND_GAMMA_FILE 2
+# define PNG_BACKGROUND_GAMMA_UNIQUE 3
+#endif
-/* write the image data */
-extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
- png_bytepp image));
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+/* Scale a 16-bit depth file down to 8-bit, accurately. */
+PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr));
+#endif
-/* writes the end of the PNG file. */
-extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
- png_infop info_ptr));
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
+#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */
+/* Strip the second byte of information from a 16-bit depth file. */
+PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr));
+#endif
-/* read the end of the PNG file. */
-extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
- png_infop info_ptr));
+#ifdef PNG_READ_QUANTIZE_SUPPORTED
+/* Turn on quantizing, and reduce the palette to the number of colors
+ * available.
+ */
+PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr,
+ png_colorp palette, int num_palette, int maximum_colors,
+ png_const_uint_16p histogram, int full_quantize));
+#endif
-/* free any memory associated with the png_info_struct */
-extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
- png_infopp info_ptr_ptr));
+#ifdef PNG_READ_GAMMA_SUPPORTED
+/* The threshold on gamma processing is configurable but hard-wired into the
+ * library. The following is the floating point variant.
+ */
+#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001)
+
+/* Handle gamma correction. Screen_gamma=(display_exponent).
+ * NOTE: this API simply sets the screen and file gamma values. It will
+ * therefore override the value for gamma in a PNG file if it is called after
+ * the file header has been read - use with care - call before reading the PNG
+ * file for best results!
+ *
+ * These routines accept the same gamma values as png_set_alpha_mode (described
+ * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either
+ * API (floating point or fixed.) Notice, however, that the 'file_gamma' value
+ * is the inverse of a 'screen gamma' value.
+ */
+PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr,
+ double screen_gamma, double override_file_gamma))
+PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr,
+ png_fixed_point screen_gamma, png_fixed_point override_file_gamma))
+#endif
+
+#ifdef PNG_WRITE_FLUSH_SUPPORTED
+/* Set how many lines between output flushes - 0 for no flushing */
+PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows));
+/* Flush the current PNG output buffer */
+PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr));
+#endif
+
+/* Optional update palette with requested transformations */
+PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr));
+
+/* Optional call to update the users info structure */
+PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr,
+ png_inforp info_ptr));
-/* free any memory associated with the png_struct and the png_info_structs */
-extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
- png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read one or more rows of image data. */
+PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row,
+ png_bytepp display_row, png_uint_32 num_rows));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read a row of data. */
+PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row,
+ png_bytep display_row));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the whole image into memory at once. */
+PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image));
+#endif
+
+/* Write a row of image data */
+PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr,
+ png_const_bytep row));
-/* free all memory used by the read (old method - NOT DLL EXPORTED) */
-extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_infop end_info_ptr));
+/* Write a few rows of image data: (*row) is not written; however, the type
+ * is declared as writeable to maintain compatibility with previous versions
+ * of libpng and to allow the 'display_row' array from read_rows to be passed
+ * unchanged to write_rows.
+ */
+PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row,
+ png_uint_32 num_rows));
+
+/* Write the image data */
+PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image));
+
+/* Write the end of the PNG file. */
+PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr,
+ png_inforp info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the end of the PNG file. */
+PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr));
+#endif
-/* free any memory associated with the png_struct and the png_info_structs */
-extern PNG_EXPORT(void,png_destroy_write_struct)
- PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
+/* Free any memory associated with the png_info_struct */
+PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr,
+ png_infopp info_ptr_ptr));
-/* free any memory used in info_ptr struct (old method - NOT DLL EXPORTED) */
-extern void png_write_destroy_info PNGARG((png_infop info_ptr));
+/* Free any memory associated with the png_struct and the png_info_structs */
+PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr,
+ png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
-/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
-extern void png_write_destroy PNGARG((png_structp png_ptr));
+/* Free any memory associated with the png_struct and the png_info_structs */
+PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr,
+ png_infopp info_ptr_ptr));
-/* set the libpng method of handling chunk CRC errors */
-extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
- int crit_action, int ancil_action));
+/* Set the libpng method of handling chunk CRC errors */
+PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action,
+ int ancil_action));
-/* Values for png_set_crc_action() to say how to handle CRC errors in
+/* Values for png_set_crc_action() say how to handle CRC errors in
* ancillary and critical chunks, and whether to use the data contained
* therein. Note that it is impossible to "discard" data in a critical
* chunk. For versions prior to 0.90, the action was always error/quit,
* header file (zlib.h) for an explination of the compression functions.
*/
-/* set the filtering method(s) used by libpng. Currently, the only valid
+/* Set the filtering method(s) used by libpng. Currently, the only valid
* value for "method" is 0.
*/
-extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
- int filters));
+PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method,
+ int filters));
/* Flags for png_set_filter() to say which filters to use. The flags
* are chosen so that they don't conflict with real filter types
#define PNG_FILTER_VALUE_PAETH 4
#define PNG_FILTER_VALUE_LAST 5
-#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
+#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */
/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
* defines, either the default (minimum-sum-of-absolute-differences), or
* the experimental method (weighted-minimum-sum-of-absolute-differences).
* the weights and costs are set to 1.0, this degenerates the WEIGHTED method
* to the UNWEIGHTED method, but with added encoding time/computation.
*/
-extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
- int heuristic_method, int num_weights, png_doublep filter_weights,
- png_doublep filter_costs));
+PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr,
+ int heuristic_method, int num_weights, png_const_doublep filter_weights,
+ png_const_doublep filter_costs))
+PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
+ (png_structrp png_ptr, int heuristic_method, int num_weights,
+ png_const_fixed_point_p filter_weights,
+ png_const_fixed_point_p filter_costs))
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
/* Heuristic used for row filter selection. These defines should NOT be
#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
+#ifdef PNG_WRITE_SUPPORTED
/* Set the library compression level. Currently, valid values range from
* 0 - 9, corresponding directly to the zlib compression levels 0 - 9
* (0 - no compression, 9 - "maximal" compression). Note that tests have
* for PNG images, and do considerably fewer caclulations. In the future,
* these values may not correspond directly to the zlib compression levels.
*/
-extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
- int level));
+PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr,
+ int level));
-extern PNG_EXPORT(void,png_set_compression_mem_level)
- PNGARG((png_structp png_ptr, int mem_level));
+PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr,
+ int mem_level));
-extern PNG_EXPORT(void,png_set_compression_strategy)
- PNGARG((png_structp png_ptr, int strategy));
+PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr,
+ int strategy));
-extern PNG_EXPORT(void,png_set_compression_window_bits)
- PNGARG((png_structp png_ptr, int window_bits));
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr,
+ int window_bits));
+
+PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr,
+ int method));
+#endif
+
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+/* Also set zlib parameters for compressing non-IDAT chunks */
+PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr,
+ int level));
+
+PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr,
+ int mem_level));
+
+PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr,
+ int strategy));
-extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
- int method));
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+PNG_EXPORT(225, void, png_set_text_compression_window_bits,
+ (png_structrp png_ptr, int window_bits));
+
+PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr,
+ int method));
+#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
/* These next functions are called for input/output, memory, and error
* handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
* and call standard C I/O routines such as fread(), fwrite(), and
* fprintf(). These functions can be made to use other I/O routines
* at run time for those applications that need to handle I/O in a
- * different manner by calling png_set_???_fn(). See libpng.txt for
+ * different manner by calling png_set_???_fn(). See libpng-manual.txt for
* more information.
*/
-#if !defined(PNG_NO_STDIO)
+#ifdef PNG_STDIO_SUPPORTED
/* Initialize the input/output for the PNG file to the default functions. */
-extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, FILE *fp));
+PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp));
#endif
/* Replace the (error and abort), and warning functions with user
* default function will be used.
*/
-extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
- png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
+PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr,
+ png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
/* Return the user pointer associated with the error functions */
-extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
+PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr));
/* Replace the default data output functions with a user supplied one(s).
* If buffered output is not used, then output_flush_fn can be set to NULL.
* If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
* output_flush_fn will be ignored (and thus can be NULL).
+ * It is probably a mistake to use NULL for output_flush_fn if
+ * write_data_fn is not also NULL unless you have built libpng with
+ * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's
+ * default flush function, which uses the standard *FILE structure, will
+ * be used.
*/
-extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
- png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
+PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr,
+ png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
/* Replace the default data input function with a user supplied one. */
-extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
- png_voidp io_ptr, png_rw_ptr read_data_fn));
+PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr,
+ png_rw_ptr read_data_fn));
/* Return the user pointer associated with the I/O functions */
-extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
+PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr));
-extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
- png_read_status_ptr read_row_fn));
+PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr,
+ png_read_status_ptr read_row_fn));
-extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
- png_write_status_ptr write_row_fn));
+PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr,
+ png_write_status_ptr write_row_fn));
#ifdef PNG_USER_MEM_SUPPORTED
/* Replace the default memory allocation functions with user supplied one(s). */
-extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
- png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
-
+PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr,
+ png_malloc_ptr malloc_fn, png_free_ptr free_fn));
/* Return the user pointer associated with the memory functions */
-extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
-#endif /* PNG_USER_MEM_SUPPORTED */
+PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr));
+#endif
#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
-extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
- png_ptr, png_user_transform_ptr read_user_transform_fn));
+PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr,
+ png_user_transform_ptr read_user_transform_fn));
#endif
#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
- png_ptr, png_user_transform_ptr write_user_transform_fn));
+PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr,
+ png_user_transform_ptr write_user_transform_fn));
+#endif
+
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
+PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr,
+ png_voidp user_transform_ptr, int user_transform_depth,
+ int user_transform_channels));
+/* Return the user pointer associated with the user transform functions */
+PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,
+ (png_const_structrp png_ptr));
+#endif
+
+#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
+/* Return information about the row currently being processed. Note that these
+ * APIs do not fail but will return unexpected results if called outside a user
+ * transform callback. Also note that when transforming an interlaced image the
+ * row number is the row number within the sub-image of the interlace pass, so
+ * the value will increase to the height of the sub-image (not the full image)
+ * then reset to 0 for the next pass.
+ *
+ * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+ * find the output pixel (x,y) given an interlaced sub-image pixel
+ * (row,col,pass). (See below for these macros.)
+ */
+PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp));
+PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp));
+#endif
+
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+/* This callback is called only for *unknown* chunks. If
+ * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known
+ * chunks to be treated as unknown, however in this case the callback must do
+ * any processing required by the chunk (e.g. by calling the appropriate
+ * png_set_ APIs.)
+ *
+ * There is no write support - on write, by default, all the chunks in the
+ * 'unknown' list are written in the specified position.
+ *
+ * The integer return from the callback function is interpreted thus:
+ *
+ * negative: An error occured, png_chunk_error will be called.
+ * zero: The chunk was not handled, the chunk will be saved. A critical
+ * chunk will cause an error at this point unless it is to be saved.
+ * positive: The chunk was handled, libpng will ignore/discard it.
+ *
+ * See "INTERACTION WTIH USER CHUNK CALLBACKS" below for important notes about
+ * how this behavior will change in libpng 1.7
+ */
+PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr,
+ png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
+#endif
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr));
#endif
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
/* Sets the function callbacks for the push reader, and a pointer to a
* user-defined structure available to the callback functions.
*/
-extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
- png_voidp progressive_ptr,
- png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
- png_progressive_end_ptr end_fn));
-
-/* returns the user pointer associated with the push read functions */
-extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
- PNGARG((png_structp png_ptr));
+PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr,
+ png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
+ png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn));
+
+/* Returns the user pointer associated with the push read functions */
+PNG_EXPORT(91, png_voidp, png_get_progressive_ptr,
+ (png_const_structrp png_ptr));
+
+/* Function to be called when data becomes available */
+PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr,
+ png_inforp info_ptr, png_bytep buffer, png_size_t buffer_size));
+
+/* A function which may be called *only* within png_process_data to stop the
+ * processing of any more data. The function returns the number of bytes
+ * remaining, excluding any that libpng has cached internally. A subsequent
+ * call to png_process_data must supply these bytes again. If the argument
+ * 'save' is set to true the routine will first save all the pending data and
+ * will always return 0.
+ */
+PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structrp, int save));
-/* function to be called when data becomes available */
-extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
+/* A function which may be called *only* outside (after) a call to
+ * png_process_data. It returns the number of bytes of data to skip in the
+ * input. Normally it will return 0, but if it returns a non-zero value the
+ * application must skip than number of bytes of input data and pass the
+ * following data to the next call to png_process_data.
+ */
+PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp));
-/* function that combines rows. Not very much different than the
- * png_combine_row() call. Is this even used?????
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+/* Function that combines rows. 'new_row' is a flag that should come from
+ * the callback and be non-NULL if anything needs to be done; the library
+ * stores its own version of the new data internally and ignores the passed
+ * in value.
*/
-extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
- png_bytep old_row, png_bytep new_row));
+PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr,
+ png_bytep old_row, png_const_bytep new_row));
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
- png_uint_32 size));
+PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr,
+ png_alloc_size_t size), PNG_ALLOCATED);
+/* Added at libpng version 1.4.0 */
+PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr,
+ png_alloc_size_t size), PNG_ALLOCATED);
-/* frees a pointer allocated by png_malloc() */
-extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
+/* Added at libpng version 1.2.4 */
+PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr,
+ png_alloc_size_t size), PNG_ALLOCATED);
-#ifdef PNG_USER_MEM_SUPPORTED
-extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
- png_uint_32 size));
-extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
- png_voidp ptr));
-#endif /* PNG_USER_MEM_SUPPORTED */
+/* Frees a pointer allocated by png_malloc() */
+PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr));
-extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
- png_voidp s1, png_voidp s2, png_uint_32 size));
+/* Free data that was allocated internally */
+PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_uint_32 free_me, int num));
-extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
- png_voidp s1, int value, png_uint_32 size));
+/* Reassign responsibility for freeing existing data, whether allocated
+ * by libpng or by the application; this works on the png_info structure passed
+ * in, it does not change the state for other png_info structures.
+ *
+ * It is unlikely that this function works correctly as of 1.6.0 and using it
+ * may result either in memory leaks or double free of allocated data.
+ */
+PNG_EXPORTA(99, void, png_data_freer, (png_const_structrp png_ptr,
+ png_inforp info_ptr, int freer, png_uint_32 mask), PNG_DEPRECATED);
+
+/* Assignments for png_data_freer */
+#define PNG_DESTROY_WILL_FREE_DATA 1
+#define PNG_SET_WILL_FREE_DATA 1
+#define PNG_USER_WILL_FREE_DATA 2
+/* Flags for png_ptr->free_me and info_ptr->free_me */
+#define PNG_FREE_HIST 0x0008
+#define PNG_FREE_ICCP 0x0010
+#define PNG_FREE_SPLT 0x0020
+#define PNG_FREE_ROWS 0x0040
+#define PNG_FREE_PCAL 0x0080
+#define PNG_FREE_SCAL 0x0100
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+# define PNG_FREE_UNKN 0x0200
+#endif
+/* PNG_FREE_LIST 0x0400 removed in 1.6.0 because it is ignored */
+#define PNG_FREE_PLTE 0x1000
+#define PNG_FREE_TRNS 0x2000
+#define PNG_FREE_TEXT 0x4000
+#define PNG_FREE_ALL 0x7fff
+#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
-#if defined(USE_FAR_KEYWORD) /* memory model conversion function */
-extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
- int check));
-#endif /* USE_FAR_KEYWORD */
+#ifdef PNG_USER_MEM_SUPPORTED
+PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr,
+ png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED);
+PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr,
+ png_voidp ptr), PNG_DEPRECATED);
+#endif
+#ifdef PNG_ERROR_TEXT_SUPPORTED
/* Fatal error in PNG image of libpng - can't continue */
-extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
- png_const_charp error));
+PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr,
+ png_const_charp error_message), PNG_NORETURN);
/* The same, but the chunk name is prepended to the error string. */
-extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
- png_const_charp error));
+PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr,
+ png_const_charp error_message), PNG_NORETURN);
+#else
+/* Fatal error in PNG image of libpng - can't continue */
+PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN);
+#endif
+
+#ifdef PNG_WARNINGS_SUPPORTED
/* Non-fatal error in libpng. Can continue, but may have a problem. */
-extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
- png_const_charp message));
+PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr,
+ png_const_charp warning_message));
/* Non-fatal error in libpng, chunk name is prepended to message. */
-extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
- png_const_charp message));
+PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr,
+ png_const_charp warning_message));
+#endif
+
+#ifdef PNG_BENIGN_ERRORS_SUPPORTED
+/* Benign error in libpng. Can continue, but may have a problem.
+ * User can choose whether to handle as a fatal error or as a warning. */
+PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr,
+ png_const_charp warning_message));
+
+#ifdef PNG_READ_SUPPORTED
+/* Same, chunk name is prepended to message (only during read) */
+PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr,
+ png_const_charp warning_message));
+#endif
+
+PNG_EXPORT(109, void, png_set_benign_errors,
+ (png_structrp png_ptr, int allowed));
+#else
+# ifdef PNG_ALLOW_BENIGN_ERRORS
+# define png_benign_error png_warning
+# define png_chunk_benign_error png_chunk_warning
+# else
+# define png_benign_error png_error
+# define png_chunk_benign_error png_chunk_error
+# endif
+#endif
/* The png_set_<chunk> functions are for storing values in the png_info_struct.
* Similarly, the png_get_<chunk> calls are used to read values from the
* png_info_struct.
*/
/* Returns "flag" if chunk data is valid in info_ptr. */
-extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
-png_infop info_ptr, png_uint_32 flag));
+PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, png_uint_32 flag));
/* Returns number of bytes needed to hold a transformed row. */
-extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
-png_infop info_ptr));
+PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
+
+#ifdef PNG_INFO_IMAGE_SUPPORTED
+/* Returns row_pointers, which is an array of pointers to scanlines that was
+ * returned from png_read_png().
+ */
+PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
+
+/* Set row_pointers, which is an array of pointers to scanlines for use
+ * by png_write_png().
+ */
+PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_bytepp row_pointers));
+#endif
/* Returns number of color channels in image. */
-extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
-png_infop info_ptr));
+PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
#ifdef PNG_EASY_ACCESS_SUPPORTED
/* Returns image width in pixels. */
-extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
/* Returns image height in pixels. */
-extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
/* Returns image bit_depth. */
-extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
/* Returns image color_type. */
-extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
/* Returns image filter_type. */
-extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
/* Returns image interlace_type. */
-extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
/* Returns image compression_type. */
-extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
/* Returns image resolution in pixels per meter, from pHYs chunk data. */
-extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
/* Returns pixel aspect ratio, computed from pHYs chunk data. */
-extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr))
+PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr))
/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
-extern PNG_EXPORT(png_uint_32, png_get_x_offset_pixels) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-extern PNG_EXPORT(png_uint_32, png_get_y_offset_pixels) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-extern PNG_EXPORT(png_uint_32, png_get_x_offset_microns) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-extern PNG_EXPORT(png_uint_32, png_get_y_offset_microns) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
#endif /* PNG_EASY_ACCESS_SUPPORTED */
+#ifdef PNG_READ_SUPPORTED
/* Returns pointer to signature string read from PNG header */
-extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
-png_infop info_ptr));
-
-#if defined(PNG_READ_bKGD_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_color_16p *background));
-#endif /* PNG_READ_bKGD_SUPPORTED */
-
-#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED)
-extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_color_16p background));
-#endif /* PNG_READ_bKGD_SUPPORTED || PNG_WRITE_bKGD_SUPPORTED */
-
-#if defined(PNG_READ_cHRM_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
- png_infop info_ptr, double *white_x, double *white_y, double *red_x,
- double *red_y, double *green_x, double *green_y, double *blue_x,
- double *blue_y));
-#endif /* PNG_READ_cHRM_SUPPORTED */
-
-#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
-extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
- png_infop info_ptr, double white_x, double white_y, double red_x,
- double red_y, double green_x, double green_y, double blue_x, double blue_y));
-#endif /* PNG_READ_cHRM_SUPPORTED || PNG_WRITE_cHRM_SUPPORTED */
-
-#if defined(PNG_READ_gAMA_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
- png_infop info_ptr, double *file_gamma));
-#endif /* PNG_READ_gAMA_SUPPORTED */
-
-#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
-extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
- png_infop info_ptr, double file_gamma));
-#endif /* PNG_READ_gAMA_SUPPORTED || PNG_WRITE_gAMA_SUPPORTED */
-
-#if defined(PNG_READ_hIST_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_16p *hist));
-#endif /* PNG_READ_hIST_SUPPORTED */
-
-#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
-extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_16p hist));
-#endif /* PNG_READ_hIST_SUPPORTED || PNG_WRITE_hIST_SUPPORTED */
-
-extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
- int *bit_depth, int *color_type, int *interlace_type,
- int *compression_type, int *filter_type));
-
-extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
- int color_type, int interlace_type, int compression_type, int filter_type));
-
-#if defined(PNG_READ_oFFs_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 *offset_x, png_uint_32 *offset_y,
+PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr));
+#endif
+
+#ifdef PNG_bKGD_SUPPORTED
+PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_color_16p *background));
+#endif
+
+#ifdef PNG_bKGD_SUPPORTED
+PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_color_16p background));
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x,
+ double *red_y, double *green_x, double *green_y, double *blue_x,
+ double *blue_y))
+PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z,
+ double *green_X, double *green_Y, double *green_Z, double *blue_X,
+ double *blue_Y, double *blue_Z))
+PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr,
+ png_fixed_point *int_white_x, png_fixed_point *int_white_y,
+ png_fixed_point *int_red_x, png_fixed_point *int_red_y,
+ png_fixed_point *int_green_x, png_fixed_point *int_green_y,
+ png_fixed_point *int_blue_x, png_fixed_point *int_blue_y))
+PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr,
+ png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
+ png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
+ png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
+ png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
+ png_fixed_point *int_blue_Z))
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr,
+ png_inforp info_ptr,
+ double white_x, double white_y, double red_x, double red_y, double green_x,
+ double green_y, double blue_x, double blue_y))
+PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr,
+ png_inforp info_ptr, double red_X, double red_Y, double red_Z,
+ double green_X, double green_Y, double green_Z, double blue_X,
+ double blue_Y, double blue_Z))
+PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_fixed_point int_white_x,
+ png_fixed_point int_white_y, png_fixed_point int_red_x,
+ png_fixed_point int_red_y, png_fixed_point int_green_x,
+ png_fixed_point int_green_y, png_fixed_point int_blue_x,
+ png_fixed_point int_blue_y))
+PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,
+ png_fixed_point int_red_Z, png_fixed_point int_green_X,
+ png_fixed_point int_green_Y, png_fixed_point int_green_Z,
+ png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
+ png_fixed_point int_blue_Z))
+#endif
+
+#ifdef PNG_gAMA_SUPPORTED
+PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, double *file_gamma))
+PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr,
+ png_fixed_point *int_file_gamma))
+#endif
+
+#ifdef PNG_gAMA_SUPPORTED
+PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr,
+ png_inforp info_ptr, double file_gamma))
+PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_fixed_point int_file_gamma))
+#endif
+
+#ifdef PNG_hIST_SUPPORTED
+PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_uint_16p *hist));
+#endif
+
+#ifdef PNG_hIST_SUPPORTED
+PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_uint_16p hist));
+#endif
+
+PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height,
+ int *bit_depth, int *color_type, int *interlace_method,
+ int *compression_method, int *filter_method));
+
+PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
+ int color_type, int interlace_method, int compression_method,
+ int filter_method));
+
+#ifdef PNG_oFFs_SUPPORTED
+PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
int *unit_type));
-#endif /* PNG_READ_oFFs_SUPPORTED */
-
-#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
-extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 offset_x, png_uint_32 offset_y,
- int unit_type));
-#endif /* PNG_READ_oFFs_SUPPORTED || PNG_WRITE_oFFs_SUPPORTED */
-
-#if defined(PNG_READ_pCAL_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
- int *type, int *nparams, png_charp *units, png_charpp *params));
-#endif /* PNG_READ_pCAL_SUPPORTED */
-
-#if defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED)
-extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
- int type, int nparams, png_charp units, png_charpp params));
-#endif /* PNG_READ_pCAL_SUPPORTED || PNG_WRITE_pCAL_SUPPORTED */
-
-#if defined(PNG_READ_pHYs_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
-#endif /* PNG_READ_pHYs_SUPPORTED */
-
-#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
-extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
-#endif /* PNG_READ_pHYs_SUPPORTED || PNG_WRITE_pHYs_SUPPORTED */
-
-extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_colorp *palette, int *num_palette));
-
-extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_colorp palette, int num_palette));
-
-#if defined(PNG_READ_sBIT_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_color_8p *sig_bit));
-#endif /* PNG_READ_sBIT_SUPPORTED */
-
-#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
-extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_color_8p sig_bit));
-#endif /* PNG_READ_sBIT_SUPPORTED || PNG_WRITE_sBIT_SUPPORTED */
-
-#if defined(PNG_READ_sRGB_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
- png_infop info_ptr, int *intent));
-#endif /* PNG_READ_sRGB_SUPPORTED */
-
-#if defined(PNG_READ_sRGB_SUPPORTED) || defined(PNG_WRITE_sRGB_SUPPORTED)
-extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
- png_infop info_ptr, int intent));
-extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
- png_infop info_ptr, int intent));
-#endif /* PNG_READ_sRGB_SUPPORTED || PNG_WRITE_sRGB_SUPPORTED */
-
-#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
-/* png_get_text also returns the number of text chunks in text_ptr */
-extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_textp *text_ptr, int *num_text));
-#endif /* PNG_READ_tEXt_SUPPORTED || PNG_READ_zTXt_SUPPORTED */
-
-#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
- defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
-extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_textp text_ptr, int num_text));
-#endif /* PNG_READ_OR_WRITE_tEXt_OR_zTXt_SUPPORTED */
-
-#if defined(PNG_READ_tIME_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_timep *mod_time));
-#endif /* PNG_READ_tIME_SUPPORTED */
-
-#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
-extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_timep mod_time));
-#endif /* PNG_READ_tIME_SUPPORTED || PNG_WRITE_tIME_SUPPORTED */
-
-#if defined(PNG_READ_tRNS_SUPPORTED)
-extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_bytep *trans, int *num_trans,
- png_color_16p *trans_values));
-#endif /* PNG_READ_tRNS_SUPPORTED */
-
-#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED)
-extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_bytep trans, int num_trans,
- png_color_16p trans_values));
-#endif /* PNG_READ_tRNS_SUPPORTED || PNG_WRITE_tRNS_SUPPORTED */
-
-/* Define PNG_DEBUG at compile time for debugging information. Higher
- * numbers for PNG_DEBUG mean more debugging information. This has
- * only been added since version 0.95 so it is not implemented throughout
- * libpng yet, but more support will be added as needed.
- */
-#ifdef PNG_DEBUG
-#if (PNG_DEBUG > 0)
-#ifndef PNG_DEBUG_FILE
-#define PNG_DEBUG_FILE stderr
-#endif /* PNG_DEBUG_FILE */
-
-#define png_debug(l,m) if (PNG_DEBUG > l) \
- fprintf(PNG_DEBUG_FILE,"%s"m,(l==1 ? "\t" : \
- (l==2 ? "\t\t":(l>2 ? "\t\t\t":""))))
-#define png_debug1(l,m,p1) if (PNG_DEBUG > l) \
- fprintf(PNG_DEBUG_FILE,"%s"m,(l==1 ? "\t" : \
- (l==2 ? "\t\t":(l>2 ? "\t\t\t":""))),p1)
-#define png_debug2(l,m,p1,p2) if (PNG_DEBUG > l) \
- fprintf(PNG_DEBUG_FILE,"%s"m,(l==1 ? "\t" : \
- (l==2 ? "\t\t":(l>2 ? "\t\t\t":""))),p1,p2)
-#endif /* (PNG_DEBUG > 0) */
-#endif /* PNG_DEBUG */
-#ifndef png_debug
-#define png_debug(l, m)
-#endif
-#ifndef png_debug1
-#define png_debug1(l, m, p1)
-#endif
-#ifndef png_debug2
-#define png_debug2(l, m, p1, p2)
-#endif
-
-extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
-extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
-
-#ifdef PNG_NO_EXTERN
-/* this only gets included in png.c */
-png_charp
-png_get_header_version(png_structp png_ptr)
-{
- if(png_ptr == NULL)
- /* silence compiler warning about unused png_ptr */ ;
- return("\n libpng version 1.0.3 - January 14, 1999 (header)\n");
-}
#endif
-#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
-/* With these routines we avoid an integer divide, which will be slower on
- * most machines. However, it does take more operations than the corresponding
- * divide method, so it may be slower on a few RISC systems. There are two
- * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
- *
- * Note that the rounding factors are NOT supposed to be the same! 128 and
- * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
- * standard method.
- *
- * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
- */
-
- /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
-
-# define png_composite(composite, fg, alpha, bg) \
- { png_uint_16 temp = ((png_uint_16)(fg) * (png_uint_16)(alpha) + \
- (png_uint_16)(bg)*(png_uint_16)(255 - \
- (png_uint_16)(alpha)) + (png_uint_16)128); \
- (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
-
-# define png_composite_16(composite, fg, alpha, bg) \
- { png_uint_32 temp = ((png_uint_32)(fg) * (png_uint_32)(alpha) + \
- (png_uint_32)(bg)*(png_uint_32)(65535L - \
- (png_uint_32)(alpha)) + (png_uint_32)32768L); \
- (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
-
-#else /* standard method using integer division */
-
-# define png_composite(composite, fg, alpha, bg) \
- (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
- (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
- (png_uint_16)127) / 255)
-
-# define png_composite_16(composite, fg, alpha, bg) \
- (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
- (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
- (png_uint_32)32767) / (png_uint_32)65535L)
-
-#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
-
-/* These next functions are used internally in the code. They generally
- * shouldn't be used unless you are writing code to add or replace some
- * functionality in libpng. More information about most functions can
- * be found in the files where the functions are located.
- */
-
-#if defined(PNG_INTERNAL)
-
-/* Various modes of operation. Note that after an init, mode is set to
- * zero automatically when the structure is created.
- */
-#define PNG_BEFORE_IHDR 0x00
-#define PNG_HAVE_IHDR 0x01
-#define PNG_HAVE_PLTE 0x02
-#define PNG_HAVE_IDAT 0x04
-#define PNG_AFTER_IDAT 0x08
-#define PNG_HAVE_IEND 0x10
-#define PNG_HAVE_gAMA 0x20
-#define PNG_HAVE_cHRM 0x40
-#define PNG_HAVE_sRGB 0x80
-
-/* push model modes */
-#define PNG_READ_SIG_MODE 0
-#define PNG_READ_CHUNK_MODE 1
-#define PNG_READ_IDAT_MODE 2
-#define PNG_SKIP_MODE 3
-#define PNG_READ_tEXt_MODE 4
-#define PNG_READ_zTXt_MODE 5
-#define PNG_READ_DONE_MODE 6
-#define PNG_ERROR_MODE 7
-
-/* flags for the transformations the PNG library does on the image data */
-#define PNG_BGR 0x0001
-#define PNG_INTERLACE 0x0002
-#define PNG_PACK 0x0004
-#define PNG_SHIFT 0x0008
-#define PNG_SWAP_BYTES 0x0010
-#define PNG_INVERT_MONO 0x0020
-#define PNG_DITHER 0x0040
-#define PNG_BACKGROUND 0x0080
-#define PNG_BACKGROUND_EXPAND 0x0100
- /* 0x0200 unused */
-#define PNG_16_TO_8 0x0400
-#define PNG_RGBA 0x0800
-#define PNG_EXPAND 0x1000
-#define PNG_GAMMA 0x2000
-#define PNG_GRAY_TO_RGB 0x4000
-#define PNG_FILLER 0x8000
-#define PNG_PACKSWAP 0x10000L
-#define PNG_SWAP_ALPHA 0x20000L
-#define PNG_STRIP_ALPHA 0x40000L
-#define PNG_INVERT_ALPHA 0x80000L
-#define PNG_USER_TRANSFORM 0x100000L
-#define PNG_RGB_TO_GRAY_ERR 0x200000L
-#define PNG_RGB_TO_GRAY_WARN 0x400000L
-#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
-
-/* flags for png_create_struct */
-#define PNG_STRUCT_PNG 0x0001
-#define PNG_STRUCT_INFO 0x0002
-
-/* Scaling factor for filter heuristic weighting calculations */
-#define PNG_WEIGHT_SHIFT 8
-#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
-#define PNG_COST_SHIFT 3
-#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
-
-/* flags for the png_ptr->flags rather than declaring a byte for each one */
-#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
-#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
-#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
-#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
-#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
-#define PNG_FLAG_ZLIB_FINISHED 0x0020
-#define PNG_FLAG_ROW_INIT 0x0040
-#define PNG_FLAG_FILLER_AFTER 0x0080
-#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
-#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
-#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
-#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
-#define PNG_FLAG_FREE_PALETTE 0x1000
-#define PNG_FLAG_FREE_TRANS 0x2000
-#define PNG_FLAG_FREE_HIST 0x4000
-#define PNG_FLAG_HAVE_CHUNK_HEADER 0x8000L
-#define PNG_FLAG_WROTE_tIME 0x10000L
-#define PNG_FLAG_BACKGROUND_IS_GRAY 0x20000L
-
-#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
- PNG_FLAG_CRC_ANCILLARY_NOWARN)
-
-#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
- PNG_FLAG_CRC_CRITICAL_IGNORE)
-
-#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
- PNG_FLAG_CRC_CRITICAL_MASK)
-
-/* save typing and make code easier to understand */
-#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
- abs((int)((c1).green) - (int)((c2).green)) + \
- abs((int)((c1).blue) - (int)((c2).blue)))
-
-/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
-#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
-/* place to hold the signature string for a PNG file. */
-extern png_byte FARDATA png_sig[8];
-
-/* Constant strings for known chunk types. If you need to add a chunk,
- * add a string holding the name here. See png.c for more details. We
- * can't selectively include these, since we still check for chunk in the
- * wrong locations with these labels.
- */
-extern png_byte FARDATA png_IHDR[5];
-extern png_byte FARDATA png_IDAT[5];
-extern png_byte FARDATA png_IEND[5];
-extern png_byte FARDATA png_PLTE[5];
-extern png_byte FARDATA png_bKGD[5];
-extern png_byte FARDATA png_cHRM[5];
-extern png_byte FARDATA png_gAMA[5];
-extern png_byte FARDATA png_hIST[5];
-extern png_byte FARDATA png_oFFs[5];
-extern png_byte FARDATA png_pCAL[5];
-extern png_byte FARDATA png_pHYs[5];
-extern png_byte FARDATA png_sBIT[5];
-extern png_byte FARDATA png_sRGB[5];
-extern png_byte FARDATA png_tEXt[5];
-extern png_byte FARDATA png_tIME[5];
-extern png_byte FARDATA png_tRNS[5];
-extern png_byte FARDATA png_zTXt[5];
-
-#endif /* PNG_NO_EXTERN */
-
-/* Inline macros to do direct reads of bytes from the input buffer. These
- * require that you are using an architecture that uses PNG byte ordering
- * (MSB first) and supports unaligned data storage. I think that PowerPC
- * in big-endian mode and 680x0 are the only ones that will support this.
- * The x86 line of processors definitely do not. The png_get_int_32()
- * routine also assumes we are using two's complement format for negative
- * values, which is almost certainly true.
- */
-#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
-#if defined(PNG_READ_pCAL_SUPPORTED)
-#define png_get_int_32(buf) ( *((png_int_32p) (buf)))
-#endif /* PNG_READ_pCAL_SUPPORTED */
-#define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
-#define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
-#else
-#if defined(PNG_READ_pCAL_SUPPORTED)
-PNG_EXTERN png_int_32 png_get_int_32 PNGARG((png_bytep buf));
-#endif /* PNG_READ_pCAL_SUPPORTED */
-PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf));
-PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf));
-#endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
-
-/* Initialize png_ptr struct for reading, and allocate any other memory.
- * (old interface - NOT DLL EXPORTED).
- */
-extern void png_read_init PNGARG((png_structp png_ptr));
-
-/* Initialize png_ptr struct for writing, and allocate any other memory.
- * (old interface - NOT DLL EXPORTED).
- */
-extern void png_write_init PNGARG((png_structp png_ptr));
-
-/* allocate memory for an internal libpng struct */
-PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
-
-/* free memory from internal libpng struct */
-PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
-
-PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
- malloc_fn));
-PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
- png_free_ptr free_fn));
-
-/* free any memory that info_ptr points to and reset struct. */
-PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-
-/* Function to allocate memory for zlib. */
-PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
-
-/* function to free memory for zlib */
-PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
-
-/* reset the CRC variable */
-PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
-
-/* Write the "data" buffer to whatever output you are using. */
-PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
- png_size_t length));
-
-/* Read data from whatever input you are using into the "data" buffer */
-PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
- png_size_t length));
-
-/* read bytes into buf, and update png_ptr->crc */
-PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
- png_size_t length));
-
-/* read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
-PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
-
-/* read the CRC from the file and compare it to the libpng calculated CRC */
-PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
-
-/* Calculate the CRC over a section of data. Note that we are only
- * passing a maximum of 64K on systems that have this as a memory limit,
- * since this is the maximum buffer size we can specify.
- */
-PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
- png_size_t length));
-
-#if defined(PNG_WRITE_FLUSH_SUPPORTED)
-PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
+#ifdef PNG_oFFs_SUPPORTED
+PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y,
+ int unit_type));
#endif
-/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
- * The only currently known PNG chunks that use signed numbers are
- * the ancillary extension chunks, oFFs and pCAL.
- */
-PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i));
-
-#if defined(PNG_WRITE_pCAL_SUPPORTED)
-PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
+#ifdef PNG_pCAL_SUPPORTED
+PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_charp *purpose, png_int_32 *X0,
+ png_int_32 *X1, int *type, int *nparams, png_charp *units,
+ png_charpp *params));
#endif
-/* Place a 16 bit number into a buffer in PNG byte order.
- * The parameter is declared unsigned int, not png_uint_16,
- * just to avoid potential problems on pre-ANSI C compilers.
- */
-PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i));
-
-/* simple function to write the signature */
-PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
-
-/* write various chunks */
+#ifdef PNG_pCAL_SUPPORTED
+PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1,
+ int type, int nparams, png_const_charp units, png_charpp params));
+#endif
-/* Write the IHDR chunk, and update the png_struct with the necessary
- * information.
- */
-PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
- png_uint_32 height,
- int bit_depth, int color_type, int compression_type, int filter_type,
- int interlace_type));
+#ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
+ int *unit_type));
+#endif
-PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
- png_uint_32 num_pal));
+#ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
+#endif
-PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
- png_size_t length));
+PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_colorp *palette, int *num_palette));
-PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
+PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr,
+ png_inforp info_ptr, png_const_colorp palette, int num_palette));
-#if defined(PNG_WRITE_gAMA_SUPPORTED)
-PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
+#ifdef PNG_sBIT_SUPPORTED
+PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_color_8p *sig_bit));
#endif
-#if defined(PNG_WRITE_sBIT_SUPPORTED)
-PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
- int color_type));
+#ifdef PNG_sBIT_SUPPORTED
+PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_color_8p sig_bit));
#endif
-#if defined(PNG_WRITE_cHRM_SUPPORTED)
-PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
- double white_x, double white_y,
- double red_x, double red_y, double green_x, double green_y,
- double blue_x, double blue_y));
+#ifdef PNG_sRGB_SUPPORTED
+PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, int *file_srgb_intent));
#endif
-#if defined(PNG_WRITE_sRGB_SUPPORTED)
-PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
- int intent));
+#ifdef PNG_sRGB_SUPPORTED
+PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr,
+ png_inforp info_ptr, int srgb_intent));
+PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr,
+ png_inforp info_ptr, int srgb_intent));
#endif
-#if defined(PNG_WRITE_tRNS_SUPPORTED)
-PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
- png_color_16p values, int number, int color_type));
+#ifdef PNG_iCCP_SUPPORTED
+PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_charpp name, int *compression_type,
+ png_bytepp profile, png_uint_32 *proflen));
#endif
-#if defined(PNG_WRITE_bKGD_SUPPORTED)
-PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
- png_color_16p values, int color_type));
+#ifdef PNG_iCCP_SUPPORTED
+PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_charp name, int compression_type,
+ png_const_bytep profile, png_uint_32 proflen));
#endif
-#if defined(PNG_WRITE_hIST_SUPPORTED)
-PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
- int num_hist));
+#ifdef PNG_sPLT_SUPPORTED
+PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_sPLT_tpp entries));
#endif
-#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED) || \
- defined(PNG_WRITE_pCAL_SUPPORTED)
-PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
- png_charp key, png_charpp new_key));
+#ifdef PNG_sPLT_SUPPORTED
+PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_sPLT_tp entries, int nentries));
#endif
-#if defined(PNG_WRITE_tEXt_SUPPORTED)
-PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
- png_charp text, png_size_t text_len));
+#ifdef PNG_TEXT_SUPPORTED
+/* png_get_text also returns the number of text chunks in *num_text */
+PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_textp *text_ptr, int *num_text));
#endif
-#if defined(PNG_WRITE_zTXt_SUPPORTED)
-PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
- png_charp text, png_size_t text_len, int compression));
-#endif
+/* Note while png_set_text() will accept a structure whose text,
+ * language, and translated keywords are NULL pointers, the structure
+ * returned by png_get_text will always contain regular
+ * zero-terminated C strings. They might be empty strings but
+ * they will never be NULL pointers.
+ */
-#if defined(PNG_WRITE_oFFs_SUPPORTED)
-PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
- png_uint_32 x_offset, png_uint_32 y_offset, int unit_type));
+#ifdef PNG_TEXT_SUPPORTED
+PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_textp text_ptr, int num_text));
#endif
-#if defined(PNG_WRITE_pCAL_SUPPORTED)
-PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
- png_int_32 X0, png_int_32 X1, int type, int nparams,
- png_charp units, png_charpp params));
+#ifdef PNG_tIME_SUPPORTED
+PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_timep *mod_time));
#endif
-#if defined(PNG_WRITE_pHYs_SUPPORTED)
-PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
- png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
- int unit_type));
+#ifdef PNG_tIME_SUPPORTED
+PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_timep mod_time));
#endif
-#if defined(PNG_WRITE_tIME_SUPPORTED)
-PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
- png_timep mod_time));
+#ifdef PNG_tRNS_SUPPORTED
+PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans,
+ png_color_16p *trans_color));
#endif
-/* Called when finished processing a row of data */
-PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
+#ifdef PNG_tRNS_SUPPORTED
+PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr,
+ png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans,
+ png_const_color_16p trans_color));
+#endif
-/* Internal use only. Called before first row of data */
-PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
+#ifdef PNG_sCAL_SUPPORTED
+PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, int *unit, double *width, double *height))
+#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \
+ defined(PNG_FLOATING_POINT_SUPPORTED)
+/* NOTE: this API is currently implemented using floating point arithmetic,
+ * consequently it can only be used on systems with floating point support.
+ * In any case the range of values supported by png_fixed_point is small and it
+ * is highly recommended that png_get_sCAL_s be used instead.
+ */
+PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
+ png_fixed_point *width, png_fixed_point *height))
+#endif
+PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
+ png_charpp swidth, png_charpp sheight));
+
+PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr,
+ png_inforp info_ptr, int unit, double width, double height))
+PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr,
+ png_inforp info_ptr, int unit, png_fixed_point width,
+ png_fixed_point height))
+PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
+ png_inforp info_ptr, int unit,
+ png_const_charp swidth, png_const_charp sheight));
+#endif /* PNG_sCAL_SUPPORTED */
+
+#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
+/* Provide the default handling for all unknown chunks or, optionally, for
+ * specific unknown chunks.
+ *
+ * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was
+ * ignored and the default was used, the per-chunk setting only had an effect on
+ * write. If you wish to have chunk-specific handling on read in code that must
+ * work on earlier versions you must use a user chunk callback to specify the
+ * desired handling (keep or discard.)
+ *
+ * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The
+ * parameter is interpreted as follows:
+ *
+ * READ:
+ * PNG_HANDLE_CHUNK_AS_DEFAULT:
+ * Known chunks: do normal libpng processing, do not keep the chunk (but
+ * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
+ * Unknown chunks: for a specific chunk use the global default, when used
+ * as the default discard the chunk data.
+ * PNG_HANDLE_CHUNK_NEVER:
+ * Discard the chunk data.
+ * PNG_HANDLE_CHUNK_IF_SAFE:
+ * Keep the chunk data if the chunk is not critical else raise a chunk
+ * error.
+ * PNG_HANDLE_CHUNK_ALWAYS:
+ * Keep the chunk data.
+ *
+ * If the chunk data is saved it can be retrieved using png_get_unknown_chunks,
+ * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent
+ * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks
+ * it simply resets the behavior to the libpng default.
+ *
+ * INTERACTION WTIH USER CHUNK CALLBACKS:
+ * The per-chunk handling is always used when there is a png_user_chunk_ptr
+ * callback and the callback returns 0; the chunk is then always stored *unless*
+ * it is critical and the per-chunk setting is other than ALWAYS. Notice that
+ * the global default is *not* used in this case. (In effect the per-chunk
+ * value is incremented to at least IF_SAFE.)
+ *
+ * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and
+ * per-chunk defaults will be honored. If you want to preserve the current
+ * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE
+ * as the default - if you don't do this libpng 1.6 will issue a warning.
+ *
+ * If you want unhandled unknown chunks to be discarded in libpng 1.6 and
+ * earlier simply return '1' (handled).
+ *
+ * PNG_HANDLE_AS_UNKNOWN_SUPPORTED:
+ * If this is *not* set known chunks will always be handled by libpng and
+ * will never be stored in the unknown chunk list. Known chunks listed to
+ * png_set_keep_unknown_chunks will have no effect. If it is set then known
+ * chunks listed with a keep other than AS_DEFAULT will *never* be processed
+ * by libpng, in addition critical chunks must either be processed by the
+ * callback or saved.
+ *
+ * The IHDR and IEND chunks must not be listed. Because this turns off the
+ * default handling for chunks that would otherwise be recognized the
+ * behavior of libpng transformations may well become incorrect!
+ *
+ * WRITE:
+ * When writing chunks the options only apply to the chunks specified by
+ * png_set_unknown_chunks (below), libpng will *always* write known chunks
+ * required by png_set_ calls and will always write the core critical chunks
+ * (as required for PLTE).
+ *
+ * Each chunk in the png_set_unknown_chunks list is looked up in the
+ * png_set_keep_unknown_chunks list to find the keep setting, this is then
+ * interpreted as follows:
+ *
+ * PNG_HANDLE_CHUNK_AS_DEFAULT:
+ * Write safe-to-copy chunks and write other chunks if the global
+ * default is set to _ALWAYS, otherwise don't write this chunk.
+ * PNG_HANDLE_CHUNK_NEVER:
+ * Do not write the chunk.
+ * PNG_HANDLE_CHUNK_IF_SAFE:
+ * Write the chunk if it is safe-to-copy, otherwise do not write it.
+ * PNG_HANDLE_CHUNK_ALWAYS:
+ * Write the chunk.
+ *
+ * Note that the default behavior is effectively the opposite of the read case -
+ * in read unknown chunks are not stored by default, in write they are written
+ * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different
+ * - on write the safe-to-copy bit is checked, on read the critical bit is
+ * checked and on read if the chunk is critical an error will be raised.
+ *
+ * num_chunks:
+ * ===========
+ * If num_chunks is positive, then the "keep" parameter specifies the manner
+ * for handling only those chunks appearing in the chunk_list array,
+ * otherwise the chunk list array is ignored.
+ *
+ * If num_chunks is 0 the "keep" parameter specifies the default behavior for
+ * unknown chunks, as described above.
+ *
+ * If num_chunks is negative, then the "keep" parameter specifies the manner
+ * for handling all unknown chunks plus all chunks recognized by libpng
+ * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to
+ * be processed by libpng.
+ */
+PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr,
+ int keep, png_const_bytep chunk_list, int num_chunks));
-#if defined(PNG_READ_GAMMA_SUPPORTED)
-PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
-#endif
+/* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned;
+ * the result is therefore true (non-zero) if special handling is required,
+ * false for the default handling.
+ */
+PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr,
+ png_const_bytep chunk_name));
+#endif
+
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_const_unknown_chunkp unknowns,
+ int num_unknowns));
+ /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added
+ * unknowns to the location currently stored in the png_struct. This is
+ * invariably the wrong value on write. To fix this call the following API
+ * for each chunk in the list with the correct location. If you know your
+ * code won't be compiled on earlier versions you can rely on
+ * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing
+ * the correct thing.
+ */
-/* combine a row of data, dealing with alpha, etc. if requested */
-PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
- int mask));
+PNG_EXPORT(175, void, png_set_unknown_chunk_location,
+ (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location));
-#if defined(PNG_READ_INTERLACING_SUPPORTED)
-/* expand an interlaced row */
-PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
- png_bytep row, int pass, png_uint_32 transformations));
+PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_unknown_chunkpp entries));
#endif
-#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
-/* grab pixels out of a row for an interlaced pass */
-PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
- png_bytep row, int pass));
-#endif
+/* Png_free_data() will turn off the "valid" flag for anything it frees.
+ * If you need to turn it off for a chunk that your application has freed,
+ * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK);
+ */
+PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr,
+ png_inforp info_ptr, int mask));
+
+#ifdef PNG_INFO_IMAGE_SUPPORTED
+/* The "params" pointer is currently not used and is for future expansion. */
+PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr,
+ int transforms, png_voidp params));
+PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr,
+ int transforms, png_voidp params));
+#endif
+
+PNG_EXPORT(180, png_const_charp, png_get_copyright,
+ (png_const_structrp png_ptr));
+PNG_EXPORT(181, png_const_charp, png_get_header_ver,
+ (png_const_structrp png_ptr));
+PNG_EXPORT(182, png_const_charp, png_get_header_version,
+ (png_const_structrp png_ptr));
+PNG_EXPORT(183, png_const_charp, png_get_libpng_ver,
+ (png_const_structrp png_ptr));
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr,
+ png_uint_32 mng_features_permitted));
+#endif
+
+/* For use in png_set_keep_unknown, added to version 1.2.6 */
+#define PNG_HANDLE_CHUNK_AS_DEFAULT 0
+#define PNG_HANDLE_CHUNK_NEVER 1
+#define PNG_HANDLE_CHUNK_IF_SAFE 2
+#define PNG_HANDLE_CHUNK_ALWAYS 3
+#define PNG_HANDLE_CHUNK_LAST 4
+
+/* Strip the prepended error numbers ("#nnn ") from error and warning
+ * messages before passing them to the error or warning handler.
+ */
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr,
+ png_uint_32 strip_mode));
+#endif
+
+/* Added in libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr,
+ png_uint_32 user_width_max, png_uint_32 user_height_max));
+PNG_EXPORT(187, png_uint_32, png_get_user_width_max,
+ (png_const_structrp png_ptr));
+PNG_EXPORT(188, png_uint_32, png_get_user_height_max,
+ (png_const_structrp png_ptr));
+/* Added in libpng-1.4.0 */
+PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr,
+ png_uint_32 user_chunk_cache_max));
+PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max,
+ (png_const_structrp png_ptr));
+/* Added in libpng-1.4.1 */
+PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr,
+ png_alloc_size_t user_chunk_cache_max));
+PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max,
+ (png_const_structrp png_ptr));
+#endif
+
+#if defined(PNG_INCH_CONVERSIONS_SUPPORTED)
+PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+
+PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+
+PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr));
+
+PNG_FP_EXPORT(196, float, png_get_x_offset_inches,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr))
+#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
+PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr))
+#endif
+
+PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr))
+#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
+PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
+ (png_const_structrp png_ptr, png_const_inforp info_ptr))
+#endif
+
+# ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr,
+ png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
+ int *unit_type));
+# endif /* PNG_pHYs_SUPPORTED */
+#endif /* PNG_INCH_CONVERSIONS_SUPPORTED */
+
+/* Added in libpng-1.4.0 */
+#ifdef PNG_IO_STATE_SUPPORTED
+PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr));
+
+/* Removed from libpng 1.6; use png_get_io_chunk_type. */
+PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr),
+ PNG_DEPRECATED)
+
+PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
+ (png_const_structrp png_ptr));
+
+/* The flags returned by png_get_io_state() are the following: */
+# define PNG_IO_NONE 0x0000 /* no I/O at this moment */
+# define PNG_IO_READING 0x0001 /* currently reading */
+# define PNG_IO_WRITING 0x0002 /* currently writing */
+# define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */
+# define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */
+# define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */
+# define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */
+# define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */
+# define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */
+#endif /* ?PNG_IO_STATE_SUPPORTED */
+
+/* Interlace support. The following macros are always defined so that if
+ * libpng interlace handling is turned off the macros may be used to handle
+ * interlaced images within the application.
+ */
+#define PNG_INTERLACE_ADAM7_PASSES 7
-/* unfilter a row */
-PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
- png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
+/* Two macros to return the first row and first column of the original,
+ * full, image which appears in a given pass. 'pass' is in the range 0
+ * to 6 and the result is in the range 0 to 7.
+ */
+#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7)
+#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7)
-/* Choose the best filter to use and filter the row data */
-PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
- png_row_infop row_info));
+/* A macro to return the offset between pixels in the output row for a pair of
+ * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that
+ * follows. Note that ROW_OFFSET is the offset from one row to the next whereas
+ * COL_OFFSET is from one column to the next, within a row.
+ */
+#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8)
+#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1))
-/* Write out the filtered row. */
-PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
- png_bytep filtered_row));
-/* finish a row while reading, dealing with interlacing passes, etc. */
-PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
+/* Two macros to help evaluate the number of rows or columns in each
+ * pass. This is expressed as a shift - effectively log2 of the number or
+ * rows or columns in each 8x8 tile of the original image.
+ */
+#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
+#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
-/* initialize the row buffers, etc. */
-PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
-/* optional call to update the users info structure */
-PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
- png_infop info_ptr));
+/* Hence two macros to determine the number of rows or columns in a given
+ * pass of an image given its height or width. In fact these macros may
+ * return non-zero even though the sub-image is empty, because the other
+ * dimension may be empty for a small image.
+ */
+#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
+ -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
+#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
+ -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
+
+/* For the reader row callbacks (both progressive and sequential) it is
+ * necessary to find the row in the output image given a row in an interlaced
+ * image, so two more macros:
+ */
+#define PNG_ROW_FROM_PASS_ROW(y_in, pass) \
+ (((y_in)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
+#define PNG_COL_FROM_PASS_COL(x_in, pass) \
+ (((x_in)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
+
+/* Two macros which return a boolean (0 or 1) saying whether the given row
+ * or column is in a particular pass. These use a common utility macro that
+ * returns a mask for a given pass - the offset 'off' selects the row or
+ * column version. The mask has the appropriate bit set for each column in
+ * the tile.
+ */
+#define PNG_PASS_MASK(pass,off) ( \
+ ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \
+ ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0))
-/* these are the functions that do the transformations */
-#if defined(PNG_READ_FILLER_SUPPORTED)
-PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
- png_bytep row, png_uint_32 filler, png_uint_32 flags));
-#endif
+#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
+ ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
+#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
+ ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
-#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
- png_bytep row));
-#endif
+#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
+/* With these routines we avoid an integer divide, which will be slower on
+ * most machines. However, it does take more operations than the corresponding
+ * divide method, so it may be slower on a few RISC systems. There are two
+ * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
+ *
+ * Note that the rounding factors are NOT supposed to be the same! 128 and
+ * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
+ * standard method.
+ *
+ * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
+ */
-#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
- png_bytep row));
-#endif
+ /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
-#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
- png_bytep row));
-#endif
+# define png_composite(composite, fg, alpha, bg) \
+ { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \
+ * (png_uint_16)(alpha) \
+ + (png_uint_16)(bg)*(png_uint_16)(255 \
+ - (png_uint_16)(alpha)) + 128); \
+ (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
-#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
- png_bytep row));
-#endif
+# define png_composite_16(composite, fg, alpha, bg) \
+ { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \
+ * (png_uint_32)(alpha) \
+ + (png_uint_32)(bg)*(65535 \
+ - (png_uint_32)(alpha)) + 32768); \
+ (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
-#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
- defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
- png_bytep row, png_uint_32 flags));
-#endif
+#else /* Standard method using integer division */
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
-#endif
+# define png_composite(composite, fg, alpha, bg) \
+ (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
+ (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
+ 127) / 255)
-#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
-#endif
+# define png_composite_16(composite, fg, alpha, bg) \
+ (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
+ (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \
+ 32767) / 65535)
+#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
-#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
- row_info, png_bytep row));
+#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));
+PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf));
+PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf));
#endif
-#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
-PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
- png_bytep row));
-#endif
+PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr,
+ png_const_bytep buf));
+/* No png_get_int_16 -- may be added if there's a real need for it. */
-#if defined(PNG_READ_PACK_SUPPORTED)
-PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
+/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
+#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i));
#endif
-
-#if defined(PNG_READ_SHIFT_SUPPORTED)
-PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
- png_color_8p sig_bits));
+#ifdef PNG_SAVE_INT_32_SUPPORTED
+PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i));
#endif
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
+/* Place a 16-bit number into a buffer in PNG byte order.
+ * The parameter is declared unsigned int, not png_uint_16,
+ * just to avoid potential problems on pre-ANSI C compilers.
+ */
+#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
+/* No png_save_int_16 -- may be added if there's a real need for it. */
#endif
-#if defined(PNG_READ_16_TO_8_SUPPORTED)
-PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
+#ifdef PNG_USE_READ_MACROS
+/* Inline macros to do direct reads of bytes from the input buffer.
+ * The png_get_int_32() routine assumes we are using two's complement
+ * format for negative values, which is almost certainly true.
+ */
+# define PNG_get_uint_32(buf) \
+ (((png_uint_32)(*(buf)) << 24) + \
+ ((png_uint_32)(*((buf) + 1)) << 16) + \
+ ((png_uint_32)(*((buf) + 2)) << 8) + \
+ ((png_uint_32)(*((buf) + 3))))
+
+ /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
+ * function) incorrectly returned a value of type png_uint_32.
+ */
+# define PNG_get_uint_16(buf) \
+ ((png_uint_16) \
+ (((unsigned int)(*(buf)) << 8) + \
+ ((unsigned int)(*((buf) + 1)))))
+
+# define PNG_get_int_32(buf) \
+ ((png_int_32)((*(buf) & 0x80) \
+ ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \
+ : (png_int_32)png_get_uint_32(buf)))
+
+ /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h,
+ * but defining a macro name prefixed with PNG_PREFIX.
+ */
+# ifndef PNG_PREFIX
+# define png_get_uint_32(buf) PNG_get_uint_32(buf)
+# define png_get_uint_16(buf) PNG_get_uint_16(buf)
+# define png_get_int_32(buf) PNG_get_int_32(buf)
+# endif
+#else
+# ifdef PNG_PREFIX
+ /* No macros; revert to the (redefined) function */
+# define PNG_get_uint_32 (png_get_uint_32)
+# define PNG_get_uint_16 (png_get_uint_16)
+# define PNG_get_int_32 (png_get_int_32)
+# endif
#endif
-#if defined(PNG_READ_DITHER_SUPPORTED)
-PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
- png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
+/*******************************************************************************
+ * SIMPLIFIED API
+ *******************************************************************************
+ *
+ * Please read the documentation in libpng-manual.txt (TODO: write said
+ * documentation) if you don't understand what follows.
+ *
+ * The simplified API hides the details of both libpng and the PNG file format
+ * itself. It allows PNG files to be read into a very limited number of
+ * in-memory bitmap formats or to be written from the same formats. If these
+ * formats do not accomodate your needs then you can, and should, use the more
+ * sophisticated APIs above - these support a wide variety of in-memory formats
+ * and a wide variety of sophisticated transformations to those formats as well
+ * as a wide variety of APIs to manipulate ancillary information.
+ *
+ * To read a PNG file using the simplified API:
+ *
+ * 1) Declare a 'png_image' structure (see below) on the stack and set the
+ * version field to PNG_IMAGE_VERSION.
+ * 2) Call the appropriate png_image_begin_read... function.
+ * 3) Set the png_image 'format' member to the required sample format.
+ * 4) Allocate a buffer for the image and, if required, the color-map.
+ * 5) Call png_image_finish_read to read the image and, if required, the
+ * color-map into your buffers.
+ *
+ * There are no restrictions on the format of the PNG input itself; all valid
+ * color types, bit depths, and interlace methods are acceptable, and the
+ * input image is transformed as necessary to the requested in-memory format
+ * during the png_image_finish_read() step. The only caveat is that if you
+ * request a color-mapped image from a PNG that is full-color or makes
+ * complex use of an alpha channel the transformation is extremely lossy and the
+ * result may look terrible.
+ *
+ * To write a PNG file using the simplified API:
+ *
+ * 1) Declare a 'png_image' structure on the stack and memset() it to all zero.
+ * 2) Initialize the members of the structure that describe the image, setting
+ * the 'format' member to the format of the image samples.
+ * 3) Call the appropriate png_image_write... function with a pointer to the
+ * image and, if necessary, the color-map to write the PNG data.
+ *
+ * png_image is a structure that describes the in-memory format of an image
+ * when it is being read or defines the in-memory format of an image that you
+ * need to write:
+ */
+#define PNG_IMAGE_VERSION 1
-# if defined(PNG_CORRECT_PALETTE_SUPPORTED)
-PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
- png_colorp palette, int num_palette));
-# endif
-#endif
+typedef struct png_control *png_controlp;
+typedef struct
+{
+ png_controlp opaque; /* Initialize to NULL, free with png_image_free */
+ png_uint_32 version; /* Set to PNG_IMAGE_VERSION */
+ png_uint_32 width; /* Image width in pixels (columns) */
+ png_uint_32 height; /* Image height in pixels (rows) */
+ png_uint_32 format; /* Image format as defined below */
+ png_uint_32 flags; /* A bit mask containing informational flags */
+ png_uint_32 colormap_entries;
+ /* Number of entries in the color-map */
+
+ /* In the event of an error or warning the following field will be set to a
+ * non-zero value and the 'message' field will contain a '\0' terminated
+ * string with the libpng error or warning message. If both warnings and
+ * an error were encountered, only the error is recorded. If there
+ * are multiple warnings, only the first one is recorded.
+ *
+ * The upper 30 bits of this value are reserved, the low two bits contain
+ * a value as follows:
+ */
+# define PNG_IMAGE_WARNING 1
+# define PNG_IMAGE_ERROR 2
+ /*
+ * The result is a two bit code such that a value more than 1 indicates
+ * a failure in the API just called:
+ *
+ * 0 - no warning or error
+ * 1 - warning
+ * 2 - error
+ * 3 - error preceded by warning
+ */
+# define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1)
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
-#endif
+ png_uint_32 warning_or_error;
-#if defined(PNG_WRITE_PACK_SUPPORTED)
-PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
- png_bytep row, png_uint_32 bit_depth));
-#endif
+ char message[64];
+} png_image, *png_imagep;
-#if defined(PNG_WRITE_SHIFT_SUPPORTED)
-PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
- png_color_8p bit_depth));
-#endif
+/* The samples of the image have one to four channels whose components have
+ * original values in the range 0 to 1.0:
+ *
+ * 1: A single gray or luminance channel (G).
+ * 2: A gray/luminance channel and an alpha channel (GA).
+ * 3: Three red, green, blue color channels (RGB).
+ * 4: Three color channels and an alpha channel (RGBA).
+ *
+ * The components are encoded in one of two ways:
+ *
+ * a) As a small integer, value 0..255, contained in a single byte. For the
+ * alpha channel the original value is simply value/255. For the color or
+ * luminance channels the value is encoded according to the sRGB specification
+ * and matches the 8-bit format expected by typical display devices.
+ *
+ * The color/gray channels are not scaled (pre-multiplied) by the alpha
+ * channel and are suitable for passing to color management software.
+ *
+ * b) As a value in the range 0..65535, contained in a 2-byte integer. All
+ * channels can be converted to the original value by dividing by 65535; all
+ * channels are linear. Color channels use the RGB encoding (RGB end-points) of
+ * the sRGB specification. This encoding is identified by the
+ * PNG_FORMAT_FLAG_LINEAR flag below.
+ *
+ * When the simplified API needs to convert between sRGB and linear colorspaces,
+ * the actual sRGB transfer curve defined in the sRGB specification (see the
+ * article at http://en.wikipedia.org/wiki/SRGB) is used, not the gamma=1/2.2
+ * approximation used elsewhere in libpng.
+ *
+ * When an alpha channel is present it is expected to denote pixel coverage
+ * of the color or luminance channels and is returned as an associated alpha
+ * channel: the color/gray channels are scaled (pre-multiplied) by the alpha
+ * value.
+ *
+ * The samples are either contained directly in the image data, between 1 and 8
+ * bytes per pixel according to the encoding, or are held in a color-map indexed
+ * by bytes in the image data. In the case of a color-map the color-map entries
+ * are individual samples, encoded as above, and the image data has one byte per
+ * pixel to select the relevant sample from the color-map.
+ */
-#if defined(PNG_READ_BACKGROUND_SUPPORTED)
-PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
- png_color_16p trans_values, png_color_16p background,
- png_color_16p background_1,
- png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
- png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
- png_uint_16pp gamma_16_to_1, int gamma_shift));
-#endif
+/* PNG_FORMAT_*
+ *
+ * #defines to be used in png_image::format. Each #define identifies a
+ * particular layout of sample data and, if present, alpha values. There are
+ * separate defines for each of the two component encodings.
+ *
+ * A format is built up using single bit flag values. All combinations are
+ * valid. Formats can be built up from the flag values or you can use one of
+ * the predefined values below. When testing formats always use the FORMAT_FLAG
+ * macros to test for individual features - future versions of the library may
+ * add new flags.
+ *
+ * When reading or writing color-mapped images the format should be set to the
+ * format of the entries in the color-map then png_image_{read,write}_colormap
+ * called to read or write the color-map and set the format correctly for the
+ * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly!
+ *
+ * NOTE: libpng can be built with particular features disabled, if you see
+ * compiler errors because the definition of one of the following flags has been
+ * compiled out it is because libpng does not have the required support. It is
+ * possible, however, for the libpng configuration to enable the format on just
+ * read or just write; in that case you may see an error at run time. You can
+ * guard against this by checking for the definition of the appropriate
+ * "_SUPPORTED" macro, one of:
+ *
+ * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED
+ */
+#define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */
+#define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */
+#define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2 byte channels else 1 byte */
+#define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */
-#if defined(PNG_READ_GAMMA_SUPPORTED)
-PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
- png_bytep gamma_table, png_uint_16pp gamma_16_table,
- int gamma_shift));
+#ifdef PNG_FORMAT_BGR_SUPPORTED
+# define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */
#endif
-#if defined(PNG_READ_EXPAND_SUPPORTED)
-PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
- png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
-PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
- png_bytep row, png_color_16p trans_value));
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
+# define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */
#endif
-/* The following decodes the appropriate chunks, and does error correction,
- * then calls the appropriate callback for the chunk if it is valid.
+/* Commonly used formats have predefined macros.
+ *
+ * First the single byte (sRGB) formats:
+ */
+#define PNG_FORMAT_GRAY 0
+#define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA
+#define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST)
+#define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR
+#define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR)
+#define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA)
+#define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST)
+#define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA)
+#define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST)
+
+/* Then the linear 2-byte formats. When naming these "Y" is used to
+ * indicate a luminance (gray) channel.
*/
+#define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR
+#define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA)
+#define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR)
+#define PNG_FORMAT_LINEAR_RGB_ALPHA \
+ (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA)
+
+/* With color-mapped formats the image data is one byte for each pixel, the byte
+ * is an index into the color-map which is formatted as above. To obtain a
+ * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP
+ * to one of the above definitions, or you can use one of the definitions below.
+ */
+#define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP)
+
+/* PNG_IMAGE macros
+ *
+ * These are convenience macros to derive information from a png_image
+ * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the
+ * actual image sample values - either the entries in the color-map or the
+ * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values
+ * for the pixels and will always return 1 for color-mapped formats. The
+ * remaining macros return information about the rows in the image and the
+ * complete image.
+ *
+ * NOTE: All the macros that take a png_image::format parameter are compile time
+ * constants if the format parameter is, itself, a constant. Therefore these
+ * macros can be used in array declarations and case labels where required.
+ * Similarly the macros are also pre-processor constants (sizeof is not used) so
+ * they can be used in #if tests.
+ *
+ * First the information about the samples.
+ */
+#define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\
+ (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1)
+ /* Return the total number of channels in a given format: 1..4 */
+
+#define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\
+ ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1)
+ /* Return the size in bytes of a single component of a pixel or color-map
+ * entry (as appropriate) in the image: 1 or 2.
+ */
-/* decode the IHDR chunk */
-PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
+#define PNG_IMAGE_SAMPLE_SIZE(fmt)\
+ (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt))
+ /* This is the size of the sample data for one sample. If the image is
+ * color-mapped it is the size of one color-map entry (and image pixels are
+ * one byte in size), otherwise it is the size of one image pixel.
+ */
-#if defined(PNG_READ_gAMA_SUPPORTED)
-PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\
+ (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256)
+ /* The maximum size of the color-map required by the format expressed in a
+ * count of components. This can be used to compile-time allocate a
+ * color-map:
+ *
+ * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)];
+ *
+ * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)];
+ *
+ * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the
+ * information from one of the png_image_begin_read_ APIs and dynamically
+ * allocate the required memory.
+ */
-#if defined(PNG_READ_sBIT_SUPPORTED)
-PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+/* Corresponding information about the pixels */
+#define PNG_IMAGE_PIXEL_(test,fmt)\
+ (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt))
-#if defined(PNG_READ_cHRM_SUPPORTED)
-PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_PIXEL_CHANNELS(fmt)\
+ PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt)
+ /* The number of separate channels (components) in a pixel; 1 for a
+ * color-mapped image.
+ */
-#if defined(PNG_READ_sRGB_SUPPORTED)
-PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\
+ PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt)
+ /* The size, in bytes, of each component in a pixel; 1 for a color-mapped
+ * image.
+ */
-#if defined(PNG_READ_tRNS_SUPPORTED)
-PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt)
+ /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */
-#if defined(PNG_READ_bKGD_SUPPORTED)
-PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+/* Information about the whole row, or whole image */
+#define PNG_IMAGE_ROW_STRIDE(image)\
+ (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width)
+ /* Return the total number of components in a single row of the image; this
+ * is the minimum 'row stride', the minimum count of components between each
+ * row. For a color-mapped image this is the minimum number of bytes in a
+ * row.
+ */
-#if defined(PNG_READ_hIST_SUPPORTED)
-PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\
+ (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride))
+ /* Return the size, in bytes, of an image buffer given a png_image and a row
+ * stride - the number of components to leave space for in each row.
+ */
-#if defined(PNG_READ_oFFs_SUPPORTED)
-PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_SIZE(image)\
+ PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image))
+ /* Return the size, in bytes, of the image in memory given just a png_image;
+ * the row stride is the minimum stride required for the image.
+ */
-#if defined(PNG_READ_pCAL_SUPPORTED)
-PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_COLORMAP_SIZE(image)\
+ (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries)
+ /* Return the size, in bytes, of the color-map of this image. If the image
+ * format is not a color-map format this will return a size sufficient for
+ * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if
+ * you don't want to allocate a color-map in this case.
+ */
-#if defined(PNG_READ_pHYs_SUPPORTED)
-PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+/* PNG_IMAGE_FLAG_*
+ *
+ * Flags containing additional information about the image are held in the
+ * 'flags' field of png_image.
+ */
+#define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01
+ /* This indicates the the RGB values of the in-memory bitmap do not
+ * correspond to the red, green and blue end-points defined by sRGB.
+ */
-#if defined(PNG_READ_tIME_SUPPORTED)
-PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_FLAG_FAST 0x02
+ /* On write emphasise speed over compression; the resultant PNG file will be
+ * larger but will be produced significantly faster, particular for large
+ * images. Do not use this option for images which will be distributed, only
+ * used it when producing intermediate files that will be read back in
+ * repeatedly. For a typical 24-bit image the option will double the read
+ * speed at the cost of increasing the image size by 25%, however for many
+ * more compressible images the PNG file can be 10 times larger with only a
+ * slight speed gain.
+ */
-#if defined(PNG_READ_tEXt_SUPPORTED)
-PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#define PNG_IMAGE_FLAG_16BIT_sRGB 0x04
+ /* On read if the image is a 16-bit per component image and there is no gAMA
+ * or sRGB chunk assume that the components are sRGB encoded. Notice that
+ * images output by the simplified API always have gamma information; setting
+ * this flag only affects the interpretation of 16-bit images from an
+ * external source. It is recommended that the application expose this flag
+ * to the user; the user can normally easily recognize the difference between
+ * linear and sRGB encoding. This flag has no effect on write - the data
+ * passed to the write APIs must have the correct encoding (as defined
+ * above.)
+ *
+ * If the flag is not set (the default) input 16-bit per component data is
+ * assumed to be linear.
+ *
+ * NOTE: the flag can only be set after the png_image_begin_read_ call,
+ * because that call initializes the 'flags' field.
+ */
-#if defined(PNG_READ_zTXt_SUPPORTED)
-PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
- png_uint_32 length));
-#endif
+#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
+/* READ APIs
+ * ---------
+ *
+ * The png_image passed to the read APIs must have been initialized by setting
+ * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.)
+ */
+#ifdef PNG_STDIO_SUPPORTED
+PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image,
+ const char *file_name));
+ /* The named file is opened for read and the image header is filled in
+ * from the PNG header in the file.
+ */
-PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 length));
+PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image,
+ FILE* file));
+ /* The PNG header is read from the stdio FILE object. */
+#endif /* PNG_STDIO_SUPPORTED */
+
+PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image,
+ png_const_voidp memory, png_size_t size));
+ /* The PNG header is read from the given memory buffer. */
+
+PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image,
+ png_const_colorp background, void *buffer, png_int_32 row_stride,
+ void *colormap));
+ /* Finish reading the image into the supplied buffer and clean up the
+ * png_image structure.
+ *
+ * row_stride is the step, in byte or 2-byte units as appropriate,
+ * between adjacent rows. A positive stride indicates that the top-most row
+ * is first in the buffer - the normal top-down arrangement. A negative
+ * stride indicates that the bottom-most row is first in the buffer.
+ *
+ * background need only be supplied if an alpha channel must be removed from
+ * a png_byte format and the removal is to be done by compositing on a solid
+ * color; otherwise it may be NULL and any composition will be done directly
+ * onto the buffer. The value is an sRGB color to use for the background,
+ * for grayscale output the green channel is used.
+ *
+ * background must be supplied when an alpha channel must be removed from a
+ * single byte color-mapped output format, in other words if:
+ *
+ * 1) The original format from png_image_begin_read_from_* had
+ * PNG_FORMAT_FLAG_ALPHA set.
+ * 2) The format set by the application does not.
+ * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and
+ * PNG_FORMAT_FLAG_LINEAR *not* set.
+ *
+ * For linear output removing the alpha channel is always done by compositing
+ * on black and background is ignored.
+ *
+ * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must
+ * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE.
+ * image->colormap_entries will be updated to the actual number of entries
+ * written to the colormap; this may be less than the original value.
+ */
-PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
- png_bytep chunk_name));
+PNG_EXPORT(238, void, png_image_free, (png_imagep image));
+ /* Free any data allocated by libpng in image->opaque, setting the pointer to
+ * NULL. May be called at any time after the structure is initialized.
+ */
+#endif /* PNG_SIMPLIFIED_READ_SUPPORTED */
+
+#ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
+/* WRITE APIS
+ * ----------
+ * For write you must initialize a png_image structure to describe the image to
+ * be written. To do this use memset to set the whole structure to 0 then
+ * initialize fields describing your image.
+ *
+ * version: must be set to PNG_IMAGE_VERSION
+ * opaque: must be initialized to NULL
+ * width: image width in pixels
+ * height: image height in rows
+ * format: the format of the data (image and color-map) you wish to write
+ * flags: set to 0 unless one of the defined flags applies; set
+ * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB
+ * values do not correspond to the colors in sRGB.
+ * colormap_entries: set to the number of entries in the color-map (0 to 256)
+ */
+PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image,
+ const char *file, int convert_to_8bit, const void *buffer,
+ png_int_32 row_stride, const void *colormap));
+ /* Write the image to the named file. */
+
+PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
+ int convert_to_8_bit, const void *buffer, png_int_32 row_stride,
+ const void *colormap));
+ /* Write the image to the given (FILE*). */
+
+/* With both write APIs if image is in one of the linear formats with 16-bit
+ * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG
+ * gamma encoded according to the sRGB specification, otherwise a 16-bit linear
+ * encoded PNG file is written.
+ *
+ * With color-mapped data formats the colormap parameter point to a color-map
+ * with at least image->colormap_entries encoded in the specified format. If
+ * the format is linear the written PNG color-map will be converted to sRGB
+ * regardless of the convert_to_8_bit flag.
+ *
+ * With all APIs row_stride is handled as in the read APIs - it is the spacing
+ * from one row to the next in component sized units (1 or 2 bytes) and if
+ * negative indicates a bottom-up row layout in the buffer.
+ *
+ * Note that the write API does not support interlacing or sub-8-bit pixels.
+ */
+#endif /* PNG_SIMPLIFIED_WRITE_SUPPORTED */
+/*******************************************************************************
+ * END OF SIMPLIFIED API
+ ******************************************************************************/
+
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+PNG_EXPORT(242, void, png_set_check_for_invalid_index,
+ (png_structrp png_ptr, int allowed));
+# ifdef PNG_GET_PALETTE_MAX_SUPPORTED
+PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr,
+ png_const_infop info_ptr));
+# endif
+#endif /* CHECK_FOR_INVALID_INDEX */
-/* handle the transformations for reading and writing */
-PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
+/*******************************************************************************
+ * IMPLEMENTATION OPTIONS
+ *******************************************************************************
+ *
+ * Support for arbitrary implementation-specific optimizations. The API allows
+ * particular options to be turned on or off. 'Option' is the number of the
+ * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given
+ * by the PNG_OPTION_ defines below.
+ *
+ * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions,
+ * are detected at run time, however sometimes it may be impossible
+ * to do this in user mode, in which case it is necessary to discover
+ * the capabilities in an OS specific way. Such capabilities are
+ * listed here when libpng has support for them and must be turned
+ * ON by the application if present.
+ *
+ * SOFTWARE: sometimes software optimizations actually result in performance
+ * decrease on some architectures or systems, or with some sets of
+ * PNG images. 'Software' options allow such optimizations to be
+ * selected at run time.
+ */
+#ifdef PNG_SET_OPTION_SUPPORTED
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+# define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */
+#endif
+#define PNG_OPTION_NEXT 2 /* Next option - numbers must be even */
-PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
+/* Return values: NOTE: there are four values and 'off' is *not* zero */
+#define PNG_OPTION_UNSET 0 /* Unset - defaults to off */
+#define PNG_OPTION_INVALID 1 /* Option number out of range */
+#define PNG_OPTION_OFF 2
+#define PNG_OPTION_ON 3
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
- png_uint_32 length));
-PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
- png_bytep buffer, png_size_t length));
-PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
- png_bytep buffer, png_size_t buffer_length));
-PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
- png_bytep buffer, png_size_t buffer_length));
-PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 length));
-PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
-PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
-#if defined(PNG_READ_tEXt_SUPPORTED)
-PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 length));
-PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
- png_infop info_ptr));
-#endif
-#if defined(PNG_READ_zTXt_SUPPORTED)
-PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
- png_infop info_ptr, png_uint_32 length));
-PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
- png_infop info_ptr));
+PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
+ int onoff));
#endif
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+/*******************************************************************************
+ * END OF HARDWARE OPTIONS
+ ******************************************************************************/
+
+/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
+ * defs, scripts/pnglibconf.h, and scripts/pnglibconf.h.prebuilt
+ */
-#endif /* PNG_INTERNAL */
+/* The last ordinal number (this is the *last* one already used; the next
+ * one to use is one more than this.) Maintainer, remember to add an entry to
+ * scripts/symbols.def as well.
+ */
+#ifdef PNG_EXPORT_LAST_ORDINAL
+ PNG_EXPORT_LAST_ORDINAL(244);
+#endif
#ifdef __cplusplus
}
#endif
-/* do not put anything past this line */
-#endif /* _PNG_H */
+#endif /* PNG_VERSION_INFO_ONLY */
+/* Do not put anything past this line */
+#endif /* PNG_H */
projects / wxWidgets.git / blobdiff