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authoraavit <qt-info@nokia.com>2010-02-15 12:08:49 (GMT)
committeraavit <qt-info@nokia.com>2010-02-15 12:14:04 (GMT)
commite9aac1679a651107735414a56ff04621d3287526 (patch)
treefa5905e80a82847fc0dbb044ae51a62ae2cf5deb /src/3rdparty/libpng/png.h
parentc9a13228d61de352edfb0019121bc83160d3b79f (diff)
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Add libpng 1.4.0
This is a clean copy of libpng 1.2.40, except that the contribs directory has been removed, as usual. Our build modifications will follow in a separate commit.
Diffstat (limited to 'src/3rdparty/libpng/png.h')
-rw-r--r--src/3rdparty/libpng/png.h2552
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diff --git a/src/3rdparty/libpng/png.h b/src/3rdparty/libpng/png.h
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+
+/* png.h - header file for PNG reference library
+ *
+ * libpng version 1.4.0 - January 3, 2010
+ * Copyright (c) 1998-2010 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.)
+ *
+ * This code is released under the libpng license (See LICENSE, below)
+ *
+ * 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 1.4.0 - January 3, 2010: Glenn
+ * See also "Contributing Authors", below.
+ *
+ * Note about libpng version numbers:
+ *
+ * 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 [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]
+ *
+ * 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 "rcN".
+ *
+ * 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.
+ *
+ * DLLNUM will change each time there are forward or backward changes
+ * in binary compatibility (e.g., when a new feature is added).
+ *
+ * See libpng.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:
+ *
+ * If you modify libpng you may insert additional notices immediately following
+ * this sentence.
+ *
+ * This code is released under the libpng license.
+ *
+ * libpng versions 1.2.6, August 15, 2004, through 1.4.0, January 3, 2010, are
+ * Copyright (c) 2004, 2006-2010 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:
+ *
+ * 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:
+ *
+ * John Bowler
+ * Kevin Bracey
+ * Sam Bushell
+ * Magnus Holmgren
+ * Greg Roelofs
+ * Tom Tanner
+ *
+ * libpng versions 0.5, May 1995, through 0.88, January 1996, are
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ *
+ * For the purposes of this copyright and license, "Contributing Authors"
+ * is defined as the following set of individuals:
+ *
+ * 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,
+ * including, without limitation, the warranties of merchantability and of
+ * fitness for any purpose. The Contributing Authors and Group 42, Inc.
+ * assume no liability for direct, indirect, incidental, special, exemplary,
+ * or consequential damages, which may result from the use of the PNG
+ * Reference Library, even if advised of the possibility of such damage.
+ *
+ * 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.
+ *
+ * The Contributing Authors and Group 42, Inc. specifically permit, without
+ * fee, and encourage the use of this source code as a component to
+ * supporting the PNG file format in commercial products. If you use this
+ * source code in a product, acknowledgment is not required but would be
+ * 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).
+ */
+
+/*
+ * Libpng is OSI Certified Open Source Software. OSI Certified is a
+ * certification mark of the Open Source Initiative.
+ */
+
+/*
+ * 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:
+ * =========================
+ *
+ * January 3, 2010
+ *
+ * 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 1.4.0 are Y2K compliant. It is my belief that earlier
+ * versions were also Y2K compliant.
+ *
+ * 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.
+ *
+ * The integer is
+ * "png_uint_16 year" in png_time_struct.
+ *
+ * The strings are
+ * "png_charp time_buffer" in png_struct and
+ * "near_time_buffer", which is a local character string in png.c.
+ *
+ * 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
+ *
+ * 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 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
+ */
+
+#ifndef PNG_H
+#define PNG_H
+
+/* This is not the place to learn how to use libpng. The file libpng.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.
+ */
+
+/* Version information for png.h - this should match the version in png.c */
+#define PNG_LIBPNG_VER_STRING "1.4.0"
+#define PNG_HEADER_VERSION_STRING \
+ " libpng version 1.4.0 - January 3, 2010\n"
+
+#define PNG_LIBPNG_VER_SONUM 14
+#define PNG_LIBPNG_VER_DLLNUM 14
+
+/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
+#define PNG_LIBPNG_VER_MAJOR 1
+#define PNG_LIBPNG_VER_MINOR 4
+#define PNG_LIBPNG_VER_RELEASE 0
+/* This should match the numeric part of the final component of
+ * PNG_LIBPNG_VER_STRING, omitting any leading zero:
+ */
+
+#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_BETA
+
+/* 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=release
+ */
+#define PNG_LIBPNG_VER 10400 /* 1.4.0 */
+
+#ifndef PNG_VERSION_INFO_ONLY
+/* Include the compression library's header */
+#include "zlib.h"
+#endif
+
+#ifdef AIX
+#define jmpbuf __jmpbuf
+#endif
+
+/* Include all user configurable info, including optional assembler routines */
+#include "pngconf.h"
+
+/*
+ * 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
+# 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 */
+
+/* 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.
+ */
+
+/* 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.
+ */
+#define png_libpng_ver png_get_header_ver(NULL)
+
+#endif /* PNG_NO_EXTERN */
+
+/* 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
+ * be png_byte or png_uint_16 (as defined below).
+ */
+typedef struct png_color_struct
+{
+ png_byte red;
+ png_byte green;
+ png_byte blue;
+} png_color;
+typedef png_color FAR * png_colorp;
+typedef png_color FAR * FAR * png_colorpp;
+
+typedef struct png_color_16_struct
+{
+ png_byte index; /* used for palette files */
+ png_uint_16 red; /* for use in red green blue files */
+ png_uint_16 green;
+ 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 struct png_color_8_struct
+{
+ png_byte red; /* for use in red green blue files */
+ png_byte green;
+ png_byte blue;
+ 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;
+
+/*
+ * 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 FAR * png_sPLT_entryp;
+typedef png_sPLT_entry FAR * FAR * 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 FAR * png_sPLT_tp;
+typedef png_sPLT_t FAR * FAR * 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", "lang", and
+ * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
+ * However, the * structure returned by png_get_text() will always contain
+ * regular zero-terminated C strings (possibly empty), never NULL pointers,
+ * so they can be safely used in printf() and other string-handling functions.
+ */
+typedef struct png_text_struct
+{
+ 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 "")
+ or a NULL pointer */
+ png_size_t text_length; /* length of the text string */
+#ifdef PNG_iTXt_SUPPORTED
+ 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 */
+#endif
+} png_text;
+typedef png_text FAR * png_textp;
+typedef png_text FAR * FAR * 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_NONE_WR -3
+#define PNG_TEXT_COMPRESSION_zTXt_WR -2
+#define PNG_TEXT_COMPRESSION_NONE -1
+#define PNG_TEXT_COMPRESSION_zTXt 0
+#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 has always been Year 2000 compliant!
+ */
+typedef struct png_time_struct
+{
+ png_uint_16 year; /* full year, as in, 1995 */
+ png_byte month; /* month of year, 1 - 12 */
+ png_byte day; /* day of month, 1 - 31 */
+ png_byte hour; /* hour of day, 0 - 23 */
+ 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;
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
+ defined(PNG_HANDLE_AS_UNKNOWN_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.
+ */
+typedef struct png_unknown_chunk_t
+{
+ png_byte name[5];
+ png_byte *data;
+ png_size_t size;
+
+ /* libpng-using applications should NOT directly modify this byte. */
+ png_byte location; /* mode of operation at read time */
+}
+png_unknown_chunk;
+typedef png_unknown_chunk FAR * png_unknown_chunkp;
+typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
+#endif
+
+/* 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.
+ *
+ * The following members may have allocated storage attached that should be
+ * cleaned up before the structure is discarded: palette, trans, text,
+ * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
+ * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
+ * are automatically freed when the info structure is deallocated, if they were
+ * allocated internally by libpng. This behavior can be changed by means
+ * of the png_data_freer() function.
+ *
+ * More allocation details: all the chunk-reading functions that
+ * change these members go through the corresponding png_set_*
+ * functions. A function to clear these members is available: see
+ * png_free_data(). The png_set_* functions do not depend on being
+ * able to point info structure members to any of the storage they are
+ * passed (they make their own copies), EXCEPT that the png_set_text
+ * functions use the same storage passed to them in the text_ptr or
+ * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
+ * functions do not make their own copies.
+ */
+typedef struct png_info_struct
+{
+ /* the following are necessary for every PNG file */
+ png_uint_32 width PNG_DEPSTRUCT; /* width of image in pixels (from IHDR) */
+ png_uint_32 height PNG_DEPSTRUCT; /* height of image in pixels (from IHDR) */
+ png_uint_32 valid PNG_DEPSTRUCT; /* valid chunk data (see PNG_INFO_ below) */
+ png_size_t rowbytes PNG_DEPSTRUCT; /* bytes needed to hold an untransformed row */
+ png_colorp palette PNG_DEPSTRUCT; /* array of color values (valid & PNG_INFO_PLTE) */
+ png_uint_16 num_palette PNG_DEPSTRUCT; /* number of color entries in "palette" (PLTE) */
+ png_uint_16 num_trans PNG_DEPSTRUCT; /* number of transparent palette color (tRNS) */
+ png_byte bit_depth PNG_DEPSTRUCT; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
+ png_byte color_type PNG_DEPSTRUCT; /* see PNG_COLOR_TYPE_ below (from IHDR) */
+ /* The following three should have been named *_method not *_type */
+ png_byte compression_type PNG_DEPSTRUCT; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
+ png_byte filter_type PNG_DEPSTRUCT; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
+ png_byte interlace_type PNG_DEPSTRUCT; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
+
+ /* The following is informational only on read, and not used on writes. */
+ png_byte channels PNG_DEPSTRUCT; /* number of data channels per pixel (1, 2, 3, 4) */
+ png_byte pixel_depth PNG_DEPSTRUCT; /* number of bits per pixel */
+ png_byte spare_byte PNG_DEPSTRUCT; /* to align the data, and for future use */
+ png_byte signature[8] PNG_DEPSTRUCT; /* 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.
+ */
+
+#if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_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 PNG_DEPSTRUCT; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
+#endif
+
+#ifdef PNG_sRGB_SUPPORTED
+ /* GR-P, 0.96a */
+ /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
+ png_byte srgb_intent PNG_DEPSTRUCT; /* sRGB rendering intent [0, 1, 2, or 3] */
+#endif
+
+#ifdef PNG_TEXT_SUPPORTED
+ /* The tEXt, and zTXt chunks contain human-readable textual data in
+ * uncompressed, compressed, and optionally 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 PNG_DEPSTRUCT; /* number of comments read/to write */
+ int max_text PNG_DEPSTRUCT; /* current size of text array */
+ png_textp text PNG_DEPSTRUCT; /* array of comments read/to write */
+#endif /* PNG_TEXT_SUPPORTED */
+
+#ifdef PNG_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 PNG_DEPSTRUCT;
+#endif
+
+#ifdef PNG_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 PNG_DEPSTRUCT; /* significant bits in color channels */
+#endif
+
+#if defined(PNG_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_alpha PNG_DEPSTRUCT; /* alpha values for paletted image */
+ png_color_16 trans_color PNG_DEPSTRUCT; /* transparent color for non-palette image */
+#endif
+
+#if defined(PNG_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 PNG_DEPSTRUCT;
+#endif
+
+#ifdef PNG_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_int_32 x_offset PNG_DEPSTRUCT; /* x offset on page */
+ png_int_32 y_offset PNG_DEPSTRUCT; /* y offset on page */
+ png_byte offset_unit_type PNG_DEPSTRUCT; /* offset units type */
+#endif
+
+#ifdef PNG_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 PNG_DEPSTRUCT; /* horizontal pixel density */
+ png_uint_32 y_pixels_per_unit PNG_DEPSTRUCT; /* vertical pixel density */
+ png_byte phys_unit_type PNG_DEPSTRUCT; /* resolution type (see PNG_RESOLUTION_ below) */
+#endif
+
+#ifdef PNG_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 PNG_DEPSTRUCT;
+#endif
+
+#ifdef PNG_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.
+ */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float x_white PNG_DEPSTRUCT;
+ float y_white PNG_DEPSTRUCT;
+ float x_red PNG_DEPSTRUCT;
+ float y_red PNG_DEPSTRUCT;
+ float x_green PNG_DEPSTRUCT;
+ float y_green PNG_DEPSTRUCT;
+ float x_blue PNG_DEPSTRUCT;
+ float y_blue PNG_DEPSTRUCT;
+#endif
+#endif
+
+#ifdef PNG_pCAL_SUPPORTED
+ /* The pCAL chunk describes a transformation between the stored pixel
+ * values and original physical 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 PNG extensions document for a
+ * complete description of the transformations and how they should be
+ * implemented, and for a description of the ASCII parameter strings.
+ * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
+ */
+ png_charp pcal_purpose PNG_DEPSTRUCT; /* pCAL chunk description string */
+ png_int_32 pcal_X0 PNG_DEPSTRUCT; /* minimum value */
+ png_int_32 pcal_X1 PNG_DEPSTRUCT; /* maximum value */
+ png_charp pcal_units PNG_DEPSTRUCT; /* Latin-1 string giving physical units */
+ png_charpp pcal_params PNG_DEPSTRUCT; /* ASCII strings containing parameter values */
+ png_byte pcal_type PNG_DEPSTRUCT; /* equation type (see PNG_EQUATION_ below) */
+ png_byte pcal_nparams PNG_DEPSTRUCT; /* number of parameters given in pcal_params */
+#endif
+
+/* New members added in libpng-1.0.6 */
+ png_uint_32 free_me PNG_DEPSTRUCT; /* flags items libpng is responsible for freeing */
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
+ defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
+ /* Storage for unknown chunks that the library doesn't recognize. */
+ png_unknown_chunkp unknown_chunks PNG_DEPSTRUCT;
+ png_size_t unknown_chunks_num PNG_DEPSTRUCT;
+#endif
+
+#ifdef PNG_iCCP_SUPPORTED
+ /* iCCP chunk data. */
+ png_charp iccp_name PNG_DEPSTRUCT; /* profile name */
+ png_charp iccp_profile PNG_DEPSTRUCT; /* International Color Consortium profile data */
+ /* Note to maintainer: should be png_bytep */
+ png_uint_32 iccp_proflen PNG_DEPSTRUCT; /* ICC profile data length */
+ png_byte iccp_compression PNG_DEPSTRUCT; /* Always zero */
+#endif
+
+#ifdef PNG_sPLT_SUPPORTED
+ /* Data on sPLT chunks (there may be more than one). */
+ png_sPLT_tp splt_palettes PNG_DEPSTRUCT;
+ png_uint_32 splt_palettes_num PNG_DEPSTRUCT;
+#endif
+
+#ifdef PNG_sCAL_SUPPORTED
+ /* The sCAL chunk describes the actual physical dimensions of the
+ * subject matter of the graphic. The chunk contains a unit specification
+ * a byte value, and two ASCII strings representing floating-point
+ * values. The values are width and height corresponsing to one pixel
+ * in the image. This external representation is converted to double
+ * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
+ */
+ png_byte scal_unit PNG_DEPSTRUCT; /* unit of physical scale */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ double scal_pixel_width PNG_DEPSTRUCT; /* width of one pixel */
+ double scal_pixel_height PNG_DEPSTRUCT; /* height of one pixel */
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+ png_charp scal_s_width PNG_DEPSTRUCT; /* string containing height */
+ png_charp scal_s_height PNG_DEPSTRUCT; /* string containing width */
+#endif
+#endif
+
+#ifdef PNG_INFO_IMAGE_SUPPORTED
+ /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
+ /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
+ png_bytepp row_pointers PNG_DEPSTRUCT; /* the image bits */
+#endif
+
+#if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
+ png_fixed_point int_gamma PNG_DEPSTRUCT; /* gamma of image, if (valid & PNG_INFO_gAMA) */
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
+ png_fixed_point int_x_white PNG_DEPSTRUCT;
+ png_fixed_point int_y_white PNG_DEPSTRUCT;
+ png_fixed_point int_x_red PNG_DEPSTRUCT;
+ png_fixed_point int_y_red PNG_DEPSTRUCT;
+ png_fixed_point int_x_green PNG_DEPSTRUCT;
+ png_fixed_point int_y_green PNG_DEPSTRUCT;
+ png_fixed_point int_x_blue PNG_DEPSTRUCT;
+ png_fixed_point int_y_blue PNG_DEPSTRUCT;
+#endif
+
+} png_info;
+
+typedef png_info FAR * png_infop;
+typedef png_info FAR * FAR * png_infopp;
+
+/* 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 describe the color_type field in png_info. */
+/* color type masks */
+#define PNG_COLOR_MASK_PALETTE 1
+#define PNG_COLOR_MASK_COLOR 2
+#define PNG_COLOR_MASK_ALPHA 4
+
+/* color types. Note that not all combinations are legal */
+#define PNG_COLOR_TYPE_GRAY 0
+#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
+#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 1.0-1.2 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 1.0-1.2 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_INTERLACE_NONE 0 /* Non-interlaced image */
+#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
+#define PNG_INTERLACE_LAST 2 /* Not a valid value */
+
+/* These are for the oFFs chunk. These values should NOT be changed. */
+#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
+#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
+#define PNG_OFFSET_LAST 2 /* Not a valid value */
+
+/* These are for the pCAL chunk. These values should NOT be changed. */
+#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
+#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
+#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
+#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_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
+ * data in the info_struct to be written into the output file. The values
+ * of the PNG_INFO_<chunk> defines should NOT be changed.
+ */
+#define PNG_INFO_gAMA 0x0001
+#define PNG_INFO_sBIT 0x0002
+#define PNG_INFO_cHRM 0x0004
+#define PNG_INFO_PLTE 0x0008
+#define PNG_INFO_tRNS 0x0010
+#define PNG_INFO_bKGD 0x0020
+#define PNG_INFO_hIST 0x0040
+#define PNG_INFO_pHYs 0x0080
+#define PNG_INFO_oFFs 0x0100
+#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 0x8000L /* 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
+ * the routines for other purposes.
+ */
+typedef struct png_row_info_struct
+{
+ 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;
+
+/* 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.
+ */
+typedef struct png_struct_def png_struct;
+typedef png_struct FAR * png_structp;
+
+typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
+typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
+typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
+typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
+ int));
+typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
+ int));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
+typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
+typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
+ png_uint_32, int));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
+ png_row_infop, png_bytep));
+#endif
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
+#endif
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
+typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
+#endif
+#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.
+ */
+typedef void (PNGAPI *png_longjmp_ptr) PNGARG((jmp_buf, int));
+#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 */
+
+/* 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
+
+typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_alloc_size_t));
+typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
+
+/* 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.
+ */
+
+struct png_struct_def
+{
+#ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf jmpbuf PNG_DEPSTRUCT; /* used in png_error */
+ png_longjmp_ptr longjmp_fn PNG_DEPSTRUCT;/* setjmp non-local goto function. */
+#endif
+ png_error_ptr error_fn PNG_DEPSTRUCT; /* function for printing errors and aborting */
+ png_error_ptr warning_fn PNG_DEPSTRUCT; /* function for printing warnings */
+ png_voidp error_ptr PNG_DEPSTRUCT; /* user supplied struct for error functions */
+ png_rw_ptr write_data_fn PNG_DEPSTRUCT; /* function for writing output data */
+ png_rw_ptr read_data_fn PNG_DEPSTRUCT; /* function for reading input data */
+ png_voidp io_ptr PNG_DEPSTRUCT; /* ptr to application struct for I/O functions */
+
+#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
+ png_user_transform_ptr read_user_transform_fn PNG_DEPSTRUCT; /* user read transform */
+#endif
+
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
+ png_user_transform_ptr write_user_transform_fn PNG_DEPSTRUCT; /* user write transform */
+#endif
+
+/* These were added in libpng-1.0.2 */
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+ png_voidp user_transform_ptr PNG_DEPSTRUCT; /* user supplied struct for user transform */
+ png_byte user_transform_depth PNG_DEPSTRUCT; /* bit depth of user transformed pixels */
+ png_byte user_transform_channels PNG_DEPSTRUCT; /* channels in user transformed pixels */
+#endif
+#endif
+
+ png_uint_32 mode PNG_DEPSTRUCT; /* tells us where we are in the PNG file */
+ png_uint_32 flags PNG_DEPSTRUCT; /* flags indicating various things to libpng */
+ png_uint_32 transformations PNG_DEPSTRUCT; /* which transformations to perform */
+
+ z_stream zstream PNG_DEPSTRUCT; /* pointer to decompression structure (below) */
+ png_bytep zbuf PNG_DEPSTRUCT; /* buffer for zlib */
+ png_size_t zbuf_size PNG_DEPSTRUCT; /* size of zbuf */
+ int zlib_level PNG_DEPSTRUCT; /* holds zlib compression level */
+ int zlib_method PNG_DEPSTRUCT; /* holds zlib compression method */
+ int zlib_window_bits PNG_DEPSTRUCT; /* holds zlib compression window bits */
+ int zlib_mem_level PNG_DEPSTRUCT; /* holds zlib compression memory level */
+ int zlib_strategy PNG_DEPSTRUCT; /* holds zlib compression strategy */
+
+ png_uint_32 width PNG_DEPSTRUCT; /* width of image in pixels */
+ png_uint_32 height PNG_DEPSTRUCT; /* height of image in pixels */
+ png_uint_32 num_rows PNG_DEPSTRUCT; /* number of rows in current pass */
+ png_uint_32 usr_width PNG_DEPSTRUCT; /* width of row at start of write */
+ png_size_t rowbytes PNG_DEPSTRUCT; /* size of row in bytes */
+ png_size_t irowbytes PNG_DEPSTRUCT; /* size of current interlaced row in bytes */
+ png_uint_32 iwidth PNG_DEPSTRUCT; /* width of current interlaced row in pixels */
+ png_uint_32 row_number PNG_DEPSTRUCT; /* current row in interlace pass */
+ png_bytep prev_row PNG_DEPSTRUCT; /* buffer to save previous (unfiltered) row */
+ png_bytep row_buf PNG_DEPSTRUCT; /* buffer to save current (unfiltered) row */
+ png_bytep sub_row PNG_DEPSTRUCT; /* buffer to save "sub" row when filtering */
+ png_bytep up_row PNG_DEPSTRUCT; /* buffer to save "up" row when filtering */
+ png_bytep avg_row PNG_DEPSTRUCT; /* buffer to save "avg" row when filtering */
+ png_bytep paeth_row PNG_DEPSTRUCT; /* buffer to save "Paeth" row when filtering */
+ png_row_info row_info PNG_DEPSTRUCT; /* used for transformation routines */
+
+ png_uint_32 idat_size PNG_DEPSTRUCT; /* current IDAT size for read */
+ png_uint_32 crc PNG_DEPSTRUCT; /* current chunk CRC value */
+ png_colorp palette PNG_DEPSTRUCT; /* palette from the input file */
+ png_uint_16 num_palette PNG_DEPSTRUCT; /* number of color entries in palette */
+ png_uint_16 num_trans PNG_DEPSTRUCT; /* number of transparency values */
+ png_byte chunk_name[5] PNG_DEPSTRUCT; /* null-terminated name of current chunk */
+ png_byte compression PNG_DEPSTRUCT; /* file compression type (always 0) */
+ png_byte filter PNG_DEPSTRUCT; /* file filter type (always 0) */
+ png_byte interlaced PNG_DEPSTRUCT; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
+ png_byte pass PNG_DEPSTRUCT; /* current interlace pass (0 - 6) */
+ png_byte do_filter PNG_DEPSTRUCT; /* row filter flags (see PNG_FILTER_ below ) */
+ png_byte color_type PNG_DEPSTRUCT; /* color type of file */
+ png_byte bit_depth PNG_DEPSTRUCT; /* bit depth of file */
+ png_byte usr_bit_depth PNG_DEPSTRUCT; /* bit depth of users row */
+ png_byte pixel_depth PNG_DEPSTRUCT; /* number of bits per pixel */
+ png_byte channels PNG_DEPSTRUCT; /* number of channels in file */
+ png_byte usr_channels PNG_DEPSTRUCT; /* channels at start of write */
+ png_byte sig_bytes PNG_DEPSTRUCT; /* magic bytes read/written from start of file */
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+ png_uint_16 filler PNG_DEPSTRUCT; /* filler bytes for pixel expansion */
+#endif
+
+#ifdef PNG_bKGD_SUPPORTED
+ png_byte background_gamma_type PNG_DEPSTRUCT;
+# ifdef PNG_FLOATING_POINT_SUPPORTED
+ float background_gamma PNG_DEPSTRUCT;
+# endif
+ png_color_16 background PNG_DEPSTRUCT; /* background color in screen gamma space */
+#ifdef PNG_READ_GAMMA_SUPPORTED
+ png_color_16 background_1 PNG_DEPSTRUCT; /* background normalized to gamma 1.0 */
+#endif
+#endif /* PNG_bKGD_SUPPORTED */
+
+#ifdef PNG_WRITE_FLUSH_SUPPORTED
+ png_flush_ptr output_flush_fn PNG_DEPSTRUCT; /* Function for flushing output */
+ png_uint_32 flush_dist PNG_DEPSTRUCT; /* how many rows apart to flush, 0 - no flush */
+ png_uint_32 flush_rows PNG_DEPSTRUCT; /* number of rows written since last flush */
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ int gamma_shift PNG_DEPSTRUCT; /* number of "insignificant" bits 16-bit gamma */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ float gamma PNG_DEPSTRUCT; /* file gamma value */
+ float screen_gamma PNG_DEPSTRUCT; /* screen gamma value (display_exponent) */
+#endif
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ png_bytep gamma_table PNG_DEPSTRUCT; /* gamma table for 8-bit depth files */
+ png_bytep gamma_from_1 PNG_DEPSTRUCT; /* converts from 1.0 to screen */
+ png_bytep gamma_to_1 PNG_DEPSTRUCT; /* converts from file to 1.0 */
+ png_uint_16pp gamma_16_table PNG_DEPSTRUCT; /* gamma table for 16-bit depth files */
+ png_uint_16pp gamma_16_from_1 PNG_DEPSTRUCT; /* converts from 1.0 to screen */
+ png_uint_16pp gamma_16_to_1 PNG_DEPSTRUCT; /* converts from file to 1.0 */
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
+ png_color_8 sig_bit PNG_DEPSTRUCT; /* significant bits in each available channel */
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+ png_color_8 shift PNG_DEPSTRUCT; /* shift for significant bit tranformation */
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
+ || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ png_bytep trans_alpha PNG_DEPSTRUCT; /* alpha values for paletted files */
+ png_color_16 trans_color PNG_DEPSTRUCT; /* transparent color for non-paletted files */
+#endif
+
+ png_read_status_ptr read_row_fn PNG_DEPSTRUCT; /* called after each row is decoded */
+ png_write_status_ptr write_row_fn PNG_DEPSTRUCT; /* called after each row is encoded */
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+ png_progressive_info_ptr info_fn PNG_DEPSTRUCT; /* called after header data fully read */
+ png_progressive_row_ptr row_fn PNG_DEPSTRUCT; /* called after each prog. row is decoded */
+ png_progressive_end_ptr end_fn PNG_DEPSTRUCT; /* called after image is complete */
+ png_bytep save_buffer_ptr PNG_DEPSTRUCT; /* current location in save_buffer */
+ png_bytep save_buffer PNG_DEPSTRUCT; /* buffer for previously read data */
+ png_bytep current_buffer_ptr PNG_DEPSTRUCT; /* current location in current_buffer */
+ png_bytep current_buffer PNG_DEPSTRUCT; /* buffer for recently used data */
+ png_uint_32 push_length PNG_DEPSTRUCT; /* size of current input chunk */
+ png_uint_32 skip_length PNG_DEPSTRUCT; /* bytes to skip in input data */
+ png_size_t save_buffer_size PNG_DEPSTRUCT; /* amount of data now in save_buffer */
+ png_size_t save_buffer_max PNG_DEPSTRUCT; /* total size of save_buffer */
+ png_size_t buffer_size PNG_DEPSTRUCT; /* total amount of available input data */
+ png_size_t current_buffer_size PNG_DEPSTRUCT; /* amount of data now in current_buffer */
+ int process_mode PNG_DEPSTRUCT; /* what push library is currently doing */
+ int cur_palette PNG_DEPSTRUCT; /* current push library palette index */
+
+# ifdef PNG_TEXT_SUPPORTED
+ png_size_t current_text_size PNG_DEPSTRUCT; /* current size of text input data */
+ png_size_t current_text_left PNG_DEPSTRUCT; /* how much text left to read in input */
+ png_charp current_text PNG_DEPSTRUCT; /* current text chunk buffer */
+ png_charp current_text_ptr PNG_DEPSTRUCT; /* current location in current_text */
+# endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_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_DEPSTRUCT;
+ png_bytep offset_table PNG_DEPSTRUCT;
+ png_uint_16 offset_table_number PNG_DEPSTRUCT;
+ png_uint_16 offset_table_count PNG_DEPSTRUCT;
+ png_uint_16 offset_table_count_free PNG_DEPSTRUCT;
+#endif
+
+#ifdef PNG_READ_DITHER_SUPPORTED
+ png_bytep palette_lookup PNG_DEPSTRUCT; /* lookup table for dithering */
+ png_bytep dither_index PNG_DEPSTRUCT; /* index translation for palette files */
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
+ png_uint_16p hist PNG_DEPSTRUCT; /* histogram */
+#endif
+
+#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+ png_byte heuristic_method PNG_DEPSTRUCT; /* heuristic for row filter selection */
+ png_byte num_prev_filters PNG_DEPSTRUCT; /* number of weights for previous rows */
+ png_bytep prev_filters PNG_DEPSTRUCT; /* filter type(s) of previous row(s) */
+ png_uint_16p filter_weights PNG_DEPSTRUCT; /* weight(s) for previous line(s) */
+ png_uint_16p inv_filter_weights PNG_DEPSTRUCT; /* 1/weight(s) for previous line(s) */
+ png_uint_16p filter_costs PNG_DEPSTRUCT; /* relative filter calculation cost */
+ png_uint_16p inv_filter_costs PNG_DEPSTRUCT; /* 1/relative filter calculation cost */
+#endif
+
+#ifdef PNG_TIME_RFC1123_SUPPORTED
+ png_charp time_buffer PNG_DEPSTRUCT; /* String to hold RFC 1123 time text */
+#endif
+
+/* New members added in libpng-1.0.6 */
+
+ png_uint_32 free_me PNG_DEPSTRUCT; /* flags items libpng is responsible for freeing */
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+ png_voidp user_chunk_ptr PNG_DEPSTRUCT;
+ png_user_chunk_ptr read_user_chunk_fn PNG_DEPSTRUCT; /* user read chunk handler */
+#endif
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ int num_chunk_list PNG_DEPSTRUCT;
+ png_bytep chunk_list PNG_DEPSTRUCT;
+#endif
+
+/* New members added in libpng-1.0.3 */
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+ png_byte rgb_to_gray_status PNG_DEPSTRUCT;
+ /* These were changed from png_byte in libpng-1.0.6 */
+ png_uint_16 rgb_to_gray_red_coeff PNG_DEPSTRUCT;
+ png_uint_16 rgb_to_gray_green_coeff PNG_DEPSTRUCT;
+ png_uint_16 rgb_to_gray_blue_coeff PNG_DEPSTRUCT;
+#endif
+
+/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
+#if defined(PNG_MNG_FEATURES_SUPPORTED) || \
+ defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+ defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+/* Changed from png_byte to png_uint_32 at version 1.2.0 */
+ png_uint_32 mng_features_permitted PNG_DEPSTRUCT;
+#endif
+
+/* New member added in libpng-1.0.7 */
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ png_fixed_point int_gamma PNG_DEPSTRUCT;
+#endif
+
+/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+ png_byte filter_type PNG_DEPSTRUCT;
+#endif
+
+/* New members added in libpng-1.2.0 */
+
+/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_voidp mem_ptr PNG_DEPSTRUCT; /* user supplied struct for mem functions */
+ png_malloc_ptr malloc_fn PNG_DEPSTRUCT; /* function for allocating memory */
+ png_free_ptr free_fn PNG_DEPSTRUCT; /* function for freeing memory */
+#endif
+
+/* New member added in libpng-1.0.13 and 1.2.0 */
+ png_bytep big_row_buf PNG_DEPSTRUCT; /* buffer to save current (unfiltered) row */
+
+#ifdef PNG_READ_DITHER_SUPPORTED
+/* The following three members were added at version 1.0.14 and 1.2.4 */
+ png_bytep dither_sort PNG_DEPSTRUCT; /* working sort array */
+ png_bytep index_to_palette PNG_DEPSTRUCT; /* where the original index currently is */
+ /* in the palette */
+ png_bytep palette_to_index PNG_DEPSTRUCT; /* which original index points to this */
+ /* palette color */
+#endif
+
+/* New members added in libpng-1.0.16 and 1.2.6 */
+ png_byte compression_type PNG_DEPSTRUCT;
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ png_uint_32 user_width_max PNG_DEPSTRUCT;
+ png_uint_32 user_height_max PNG_DEPSTRUCT;
+ /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown
+ * chunks that can be stored (0x7fffffff means unlimited).
+ */
+ png_uint_32 user_chunk_cache_max PNG_DEPSTRUCT;
+#endif
+
+/* New member added in libpng-1.0.25 and 1.2.17 */
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
+ /* Storage for unknown chunk that the library doesn't recognize. */
+ png_unknown_chunk unknown_chunk PNG_DEPSTRUCT;
+#endif
+
+/* New members added in libpng-1.2.26 */
+ png_uint_32 old_big_row_buf_size PNG_DEPSTRUCT;
+ png_uint_32 old_prev_row_size PNG_DEPSTRUCT;
+
+/* New member added in libpng-1.2.30 */
+ png_charp chunkdata PNG_DEPSTRUCT; /* buffer for reading chunk data */
+
+/* New member added in libpng-1.4.0 */
+#ifdef PNG_IO_STATE_SUPPORTED
+ png_uint_32 io_state PNG_DEPSTRUCT;
+#endif
+};
+
+
+/* This triggers a compiler error in png.c, if png.c and png.h
+ * do not agree upon the version number.
+ */
+typedef png_structp version_1_4_0;
+
+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
+ * full explanation, see example.c for the summary. This just provides
+ * a simple one line description of the use of each function.
+ */
+
+/* Returns the version number of the library */
+extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((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));
+
+/* 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));
+
+/* 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_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_ALLOCATED;
+
+#ifdef PNG_WRITE_SUPPORTED
+extern PNG_EXPORT(png_size_t,png_get_compression_buffer_size)
+ PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+extern PNG_EXPORT(void,png_set_compression_buffer_size)
+ PNGARG((png_structp png_ptr, png_size_t size));
+#endif
+
+/* 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.
+ */
+extern PNG_EXPORT(jmp_buf*, png_set_longjmp_fn)
+ PNGARG((png_structp 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
+
+/* Reset the compression stream */
+extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
+
+/* 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)) PNG_ALLOCATED;
+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_ALLOCATED;
+#endif
+
+/* Write the PNG file signature. */
+extern PNG_EXPORT(void,png_write_sig) PNGARG((png_structp 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));
+
+/* 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));
+
+/* 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));
+
+/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
+extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
+
+/* Allocate and initialize the info structure */
+extern PNG_EXPORT(png_infop,png_create_info_struct)
+ PNGARG((png_structp png_ptr)) PNG_ALLOCATED;
+
+extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
+ png_size_t png_info_struct_size));
+
+/* Writes all the PNG information before the image. */
+extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the information before the actual image data. */
+extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#endif
+
+#ifdef PNG_TIME_RFC1123_SUPPORTED
+extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
+ PNGARG((png_structp png_ptr, png_timep ptime));
+#endif
+
+#ifdef PNG_CONVERT_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() */
+extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
+ time_t ttime));
+#endif /* PNG_CONVERT_tIME_SUPPORTED */
+
+#ifdef 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));
+extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp
+ png_ptr));
+extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp 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
+
+#ifdef 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
+
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+/* Reduce RGB to grayscale. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
+ int error_action, double red, double green ));
+#endif
+extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
+ int error_action, png_fixed_point red, png_fixed_point green ));
+extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
+ png_ptr));
+#endif
+
+extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
+ png_colorp palette));
+
+#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
+extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#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
+
+#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
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte to 8-bit Gray or 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
+/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
+extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
+ png_uint_32 filler, int flags));
+#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
+
+#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
+
+#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
+
+#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
+
+#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
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+/* Invert monochrome files */
+extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+/* Handle alpha and tRNS by replacing with a background color. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+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));
+#endif
+#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
+
+#ifdef 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
+
+#ifdef 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
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
+/* Handle gamma correction. Screen_gamma=(display_exponent) */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
+ double screen_gamma, double default_file_gamma));
+#endif
+#endif
+
+
+#ifdef 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));
+/* Flush the current PNG output buffer */
+extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
+#endif
+
+/* Optional update palette with requested transformations */
+extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
+
+/* 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));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read 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));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read a row of data. */
+extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
+ png_bytep row,
+ png_bytep display_row));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the whole image into memory at once. */
+extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
+ png_bytepp image));
+#endif
+
+/* Write a row of image data */
+extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
+ png_bytep row));
+
+/* 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));
+
+/* Write the image data */
+extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
+ png_bytepp image));
+
+/* Write the end of the PNG file. */
+extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the end of the PNG file. */
+extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#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));
+
+/* 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));
+
+/* 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));
+
+/* 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));
+
+/* Values for png_set_crc_action() to 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,
+ * whereas in version 0.90 and later, the action for CRC errors in ancillary
+ * chunks is warn/discard. These values should NOT be changed.
+ *
+ * value action:critical action:ancillary
+ */
+#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
+#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
+#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
+#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
+#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
+#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
+
+/* These functions give the user control over the scan-line filtering in
+ * libpng and the compression methods used by zlib. These functions are
+ * mainly useful for testing, as the defaults should work with most users.
+ * Those users who are tight on memory or want faster performance at the
+ * expense of compression can modify them. See the compression library
+ * header file (zlib.h) for an explination of the compression functions.
+ */
+
+/* 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));
+
+/* 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
+ * below, in case they are supplied instead of the #defined constants.
+ * These values should NOT be changed.
+ */
+#define PNG_NO_FILTERS 0x00
+#define PNG_FILTER_NONE 0x08
+#define PNG_FILTER_SUB 0x10
+#define PNG_FILTER_UP 0x20
+#define PNG_FILTER_AVG 0x40
+#define PNG_FILTER_PAETH 0x80
+#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
+ PNG_FILTER_AVG | PNG_FILTER_PAETH)
+
+/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
+ * These defines should NOT be changed.
+ */
+#define PNG_FILTER_VALUE_NONE 0
+#define PNG_FILTER_VALUE_SUB 1
+#define PNG_FILTER_VALUE_UP 2
+#define PNG_FILTER_VALUE_AVG 3
+#define PNG_FILTER_VALUE_PAETH 4
+#define PNG_FILTER_VALUE_LAST 5
+
+#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).
+ *
+ * Weights are factors >= 1.0, indicating how important it is to keep the
+ * filter type consistent between rows. Larger numbers mean the current
+ * filter is that many times as likely to be the same as the "num_weights"
+ * previous filters. This is cumulative for each previous row with a weight.
+ * There needs to be "num_weights" values in "filter_weights", or it can be
+ * NULL if the weights aren't being specified. Weights have no influence on
+ * the selection of the first row filter. Well chosen weights can (in theory)
+ * improve the compression for a given image.
+ *
+ * Costs are factors >= 1.0 indicating the relative decoding costs of a
+ * filter type. Higher costs indicate more decoding expense, and are
+ * therefore less likely to be selected over a filter with lower computational
+ * costs. There needs to be a value in "filter_costs" for each valid filter
+ * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
+ * setting the costs. Costs try to improve the speed of decompression without
+ * unduly increasing the compressed image size.
+ *
+ * A negative weight or cost indicates the default value is to be used, and
+ * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
+ * The default values for both weights and costs are currently 1.0, but may
+ * change if good general weighting/cost heuristics can be found. If both
+ * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
+ * to the UNWEIGHTED method, but with added encoding time/computation.
+ */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+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));
+#endif
+#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+
+/* Heuristic used for row filter selection. These defines should NOT be
+ * changed.
+ */
+#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
+#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
+#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
+#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
+
+/* 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
+ * shown that zlib compression levels 3-6 usually perform as well as level 9
+ * 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));
+
+extern PNG_EXPORT(void,png_set_compression_mem_level)
+ PNGARG((png_structp png_ptr, int mem_level));
+
+extern PNG_EXPORT(void,png_set_compression_strategy)
+ PNGARG((png_structp png_ptr, int strategy));
+
+extern PNG_EXPORT(void,png_set_compression_window_bits)
+ PNGARG((png_structp png_ptr, int window_bits));
+
+extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
+ int method));
+
+/* 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
+ * more information.
+ */
+
+#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, png_FILE_p fp));
+#endif
+
+/* Replace the (error and abort), and warning functions with user
+ * supplied functions. If no messages are to be printed you must still
+ * write and use replacement functions. The replacement error_fn should
+ * still do a longjmp to the last setjmp location if you are using this
+ * method of error handling. If error_fn or warning_fn is NULL, the
+ * 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));
+
+/* Return the user pointer associated with the error functions */
+extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp 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));
+
+/* 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));
+
+/* Return the user pointer associated with the I/O functions */
+extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
+
+extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp 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));
+
+#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));
+/* Return the user pointer associated with the memory functions */
+extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp 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));
+#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));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
+ 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 */
+extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
+ PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
+ png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
+extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
+ 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));
+
+/* 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));
+
+/* Function that combines rows. Not very much different than the
+ * png_combine_row() call. Is this even used?????
+ */
+extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
+ png_bytep old_row, png_bytep new_row));
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
+ png_alloc_size_t size)) PNG_ALLOCATED;
+/* Added at libpng version 1.4.0 */
+extern PNG_EXPORT(png_voidp,png_calloc) PNGARG((png_structp png_ptr,
+ png_alloc_size_t size)) PNG_ALLOCATED;
+
+/* Added at libpng version 1.2.4 */
+extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp 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));
+
+/* Free data that was allocated internally */
+extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 free_me, int num));
+/* Reassign responsibility for freeing existing data, whether allocated
+ * by libpng or by the application */
+extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int freer, png_uint_32 mask));
+/* 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
+#define PNG_FREE_UNKN 0x0200
+#define PNG_FREE_LIST 0x0400
+#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 */
+
+#ifdef PNG_USER_MEM_SUPPORTED
+extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
+ png_alloc_size_t size)) PNG_ALLOCATED;
+extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
+ png_voidp ptr));
+#endif
+
+#ifndef PNG_NO_ERROR_TEXT
+/* 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_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_message)) PNG_NORETURN;
+
+#else
+/* Fatal error in PNG image of libpng - can't continue */
+extern PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr)) PNG_NORETURN;
+#endif
+
+/* 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 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 warning_message));
+
+#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. */
+extern PNG_EXPORT(void,png_benign_error) PNGARG((png_structp png_ptr,
+ png_const_charp warning_message));
+
+/* Same, chunk name is prepended to message. */
+extern PNG_EXPORT(void,png_chunk_benign_error) PNGARG((png_structp png_ptr,
+ png_const_charp warning_message));
+
+extern PNG_EXPORT(void,png_set_benign_errors) PNGARG((png_structp
+ png_ptr, int allowed));
+#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, either storing the parameters in the passed variables, or
+ * setting pointers into the png_info_struct where the data is stored. The
+ * png_get_<chunk> functions return a non-zero value if the data was available
+ * in info_ptr, or return zero and do not change any of the parameters if the
+ * data was not available.
+ *
+ * These functions should be used instead of directly accessing png_info
+ * to avoid problems with future changes in the size and internal layout of
+ * 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));
+
+/* Returns number of bytes needed to hold a transformed row. */
+extern PNG_EXPORT(png_size_t,png_get_rowbytes) PNGARG((png_structp png_ptr,
+png_infop 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().
+ */
+extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+/* Set row_pointers, which is an array of pointers to scanlines for use
+ * by png_write_png().
+ */
+extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
+ png_infop 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));
+
+#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));
+
+/* Returns image height in pixels. */
+extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image bit_depth. */
+extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image color_type. */
+extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image filter_type. */
+extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image interlace_type. */
+extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image compression_type. */
+extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
+png_ptr, png_infop 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));
+
+/* Returns pixel aspect ratio, computed from pHYs chunk data. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+#endif
+
+/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
+extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+#endif /* PNG_EASY_ACCESS_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));
+
+#ifdef PNG_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
+
+#ifdef PNG_bKGD_SUPPORTED
+extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_color_16p background));
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+#ifdef PNG_FLOATING_POINT_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
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
+ png_infop 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));
+#endif
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+#ifdef PNG_FLOATING_POINT_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
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
+ png_infop 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));
+#endif
+#endif
+
+#ifdef PNG_gAMA_SUPPORTED
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, double *file_gamma));
+#endif
+extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_fixed_point *int_file_gamma));
+#endif
+
+#ifdef PNG_gAMA_SUPPORTED
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, double file_gamma));
+#endif
+extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_fixed_point int_file_gamma));
+#endif
+
+#ifdef PNG_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
+
+#ifdef PNG_hIST_SUPPORTED
+extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_16p hist));
+#endif
+
+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_method,
+ int *compression_method, int *filter_method));
+
+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_method, int compression_method,
+ int filter_method));
+
+#ifdef PNG_oFFs_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
+ int *unit_type));
+#endif
+
+#ifdef PNG_oFFs_SUPPORTED
+extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
+ int unit_type));
+#endif
+
+#ifdef PNG_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
+
+#ifdef PNG_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
+
+#ifdef PNG_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
+
+#ifdef PNG_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
+
+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));
+
+#ifdef PNG_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
+
+#ifdef PNG_sBIT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_color_8p sig_bit));
+#endif
+
+#ifdef PNG_sRGB_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int *intent));
+#endif
+
+#ifdef PNG_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
+
+#ifdef PNG_iCCP_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_charpp name, int *compression_type,
+ png_charpp profile, png_uint_32 *proflen));
+ /* Note to maintainer: profile should be png_bytepp */
+#endif
+
+#ifdef PNG_iCCP_SUPPORTED
+extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_charp name, int compression_type,
+ png_charp profile, png_uint_32 proflen));
+ /* Note to maintainer: profile should be png_bytep */
+#endif
+
+#ifdef PNG_sPLT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_sPLT_tpp entries));
+#endif
+
+#ifdef PNG_sPLT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_sPLT_tp entries, int nentries));
+#endif
+
+#ifdef PNG_TEXT_SUPPORTED
+/* png_get_text also returns the number of text chunks in *num_text */
+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
+
+/* 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.
+ */
+
+#ifdef PNG_TEXT_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
+
+#ifdef PNG_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
+
+#ifdef PNG_tIME_SUPPORTED
+extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_timep mod_time));
+#endif
+
+#ifdef PNG_tRNS_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_bytep *trans_alpha, int *num_trans,
+ png_color_16p *trans_color));
+#endif
+
+#ifdef PNG_tRNS_SUPPORTED
+extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_bytep trans_alpha, int num_trans,
+ png_color_16p trans_color));
+#endif
+
+#ifdef PNG_tRNS_SUPPORTED
+#endif
+
+#ifdef PNG_sCAL_SUPPORTED
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int *unit, double *width, double *height));
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
+#endif
+#endif
+#endif /* PNG_sCAL_SUPPORTED */
+
+#ifdef PNG_sCAL_SUPPORTED
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int unit, double width, double height));
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
+#endif
+#endif
+#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+/* Provide a list of chunks and how they are to be handled, if the built-in
+ handling or default unknown chunk handling is not desired. Any chunks not
+ listed will be handled in the default manner. The IHDR and IEND chunks
+ must not be listed.
+ keep = 0: follow default behaviour
+ = 1: do not keep
+ = 2: keep only if safe-to-copy
+ = 3: keep even if unsafe-to-copy
+*/
+extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
+ png_ptr, int keep, png_bytep chunk_list, int num_chunks));
+PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
+ chunk_name));
+#endif
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
+extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
+extern PNG_EXPORT(void, png_set_unknown_chunk_location)
+ PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
+extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
+ png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
+#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);
+ */
+extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
+ png_infop info_ptr, int mask));
+
+#ifdef PNG_INFO_IMAGE_SUPPORTED
+/* The "params" pointer is currently not used and is for future expansion. */
+extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
+ png_infop info_ptr,
+ int transforms,
+ png_voidp params));
+extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
+ png_infop info_ptr,
+ int transforms,
+ png_voidp params));
+#endif
+
+extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
+ 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
+
+/* 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
+extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
+ png_ptr, png_uint_32 strip_mode));
+#endif
+
+/* Added in libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
+ png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
+extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
+ png_ptr));
+extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
+ png_ptr));
+/* Added in libpng-1.4.0 */
+extern PNG_EXPORT(void,png_set_chunk_cache_max) PNGARG((png_structp
+ png_ptr, png_uint_32 user_chunk_cache_max));
+extern PNG_EXPORT(png_uint_32,png_get_chunk_cache_max)
+ PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
+PNG_EXPORT(png_uint_32,png_get_pixels_per_inch) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXPORT(png_uint_32,png_get_x_pixels_per_inch) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXPORT(png_uint_32,png_get_y_pixels_per_inch) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXPORT(float,png_get_x_offset_inches) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+PNG_EXPORT(float,png_get_y_offset_inches) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(png_uint_32,png_get_pHYs_dpi) PNGARG((png_structp png_ptr,
+png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
+#endif /* PNG_pHYs_SUPPORTED */
+#endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
+
+/* Added in libpng-1.4.0 */
+#ifdef PNG_IO_STATE_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_io_state) PNGARG((png_structp png_ptr));
+
+extern PNG_EXPORT(png_bytep,png_get_io_chunk_name)
+ PNGARG((png_structp 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 */
+
+/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
+ * defs
+ */
+
+#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)((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)((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 */
+
+#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.
+ */
+/* We could make special-case BIG_ENDIAN macros that do direct reads here */
+# 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))))
+# define png_get_uint_16(buf) \
+ (((png_uint_32)(*(buf)) << 8) + \
+ ((png_uint_32)(*((buf) + 1))))
+#ifdef PNG_GET_INT_32_SUPPORTED
+# define png_get_int_32(buf) \
+ (((png_int_32)(*(buf)) << 24) + \
+ ((png_int_32)(*((buf) + 1)) << 16) + \
+ ((png_int_32)(*((buf) + 2)) << 8) + \
+ ((png_int_32)(*((buf) + 3))))
+#endif
+#else
+extern PNG_EXPORT(png_uint_32,png_get_uint_32) PNGARG((png_bytep buf));
+extern PNG_EXPORT(png_uint_16,png_get_uint_16) PNGARG((png_bytep buf));
+#ifdef PNG_GET_INT_32_SUPPORTED
+extern PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf));
+#endif
+#endif
+extern PNG_EXPORT(png_uint_32,png_get_uint_31)
+ PNGARG((png_structp png_ptr, png_bytep buf));
+/* No png_get_int_16 -- may be added if there's a real need for it. */
+
+/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
+extern PNG_EXPORT(void,png_save_uint_32)
+ PNGARG((png_bytep buf, png_uint_32 i));
+extern PNG_EXPORT(void,png_save_int_32)
+ PNGARG((png_bytep buf, png_int_32 i));
+
+/* 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.
+ */
+extern PNG_EXPORT(void,png_save_uint_16)
+ PNGARG((png_bytep buf, unsigned int i));
+/* No png_save_int_16 -- may be added if there's a real need for it. */
+
+/* ************************************************************************* */
+
+/* Various modes of operation. Note that after an init, mode is set to
+ * zero automatically when the structure is created.
+ */
+#define PNG_HAVE_IHDR 0x01
+#define PNG_HAVE_PLTE 0x02
+#define PNG_HAVE_IDAT 0x04
+#define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */
+#define PNG_HAVE_IEND 0x10
+#define PNG_HAVE_gAMA 0x20
+#define PNG_HAVE_cHRM 0x40
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PNG_VERSION_INFO_ONLY */
+/* Do not put anything past this line */
+#endif /* PNG_H */
generated by cgit v0.12 at 2025-01-01 01:16:28 (GMT)