Update libpng to 1.6.22

third_party/libpng/png.h

 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.2.56, December 17, 2015
+ * libpng version 1.6.22, May 26, 2016
  *
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2016 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 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
- *  libpng versions 0.97, January 1998, through 1.2.56, December 17, 2015: Glenn
- *  See also "Contributing Authors", below.
+ *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
+ *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
+ *   libpng versions 0.97, January 1998, through 1.6.22, May 26, 2016:
+ *     Glenn Randers-Pehrson.
+ *   See also "Contributing Authors", below.
  */
 
 /*
  * 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 1.0.7, July 1, 2000, through 1.2.56, December 17, 2015, are
- * Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
+ * Some files in the "contrib" directory and some configure-generated
+ * files that are distributed with libpng have other copyright owners and
+ * are released under other open source licenses.
+ *
+ * libpng versions 1.0.7, July 1, 2000 through 1.6.22, May 26, 2016 are
+ * Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
  * derived from libpng-1.0.6, 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
+ *    Mans Rullgard
  *    Cosmin Truta
  *    Gilles Vollant
+ *    James Yu
  *
  * 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.
  *
+ * Some files in the "contrib" directory have other copyright owners and
+ * are released under other open source licenses.
+ *
+ *
  * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
  * Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
  * libpng-0.96, 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
  *
+ * Some files in the "scripts" directory have different copyright owners
+ * but are also released under this license.
+ *
  * libpng versions 0.89, June 1996, through 0.96, May 1997, are
  * Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
  * and are 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
  *
+ * Some files in the "scripts" directory have other copyright owners
+ * but are released under this license.
+ *
  * 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
@@ skipping 19 matching lines @@
  *   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.
  *
  * END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
+ *
+ * TRADEMARK:
+ *
+ * The name "libpng" has not been registered by the Copyright owner
+ * as a trademark in any jurisdiction.  However, because libpng has
+ * been distributed and maintained world-wide, continually since 1995,
+ * the Copyright owner claims "common-law trademark protection" in any
+ * jurisdiction where common-law trademark is recognized.
+ *
+ * OSI CERTIFICATION:
+ *
+ * Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is
+ * a certification mark of the Open Source Initiative. OSI has not addressed
+ * the additional disclaimers inserted at version 1.0.7.
+ *
+ * EXPORT CONTROL:
+ *
+ * The Copyright owner believes that the Export Control Classification
+ * Number (ECCN) for libpng is EAR99, which means not subject to export
+ * controls or International Traffic in Arms Regulations (ITAR) because
+ * it is open source, publicly available software, that does not contain
+ * any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
+ * 734.7(b).
  */
 
 /*
  * 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 Open Source is
- * a certification mark of the Open Source Initiative. OSI has not addressed
- * the additional disclaimers inserted at version 1.0.7.
- */
-
-/*
  * 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.
  */
 
 /* Note about libpng version numbers:
  *
  *    Due to various miscommunications, unforeseen code incompatibilities
@@ skipping 34 matching lines @@
  *    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)
  *    ...
  *    1.0.19                  10    10019  10.so.0.19[.0]
  *    ...
- *    1.0.66                  10    10066  10.so.0.66[.0]
  *    1.2.56                  13    10256  12.so.0.56[.0]
+ *    ...
+ *    1.5.27                  15    10527  15.so.15.27[.0]
+ *    ...
+ *    1.6.22                  16    10622  16.so.16.22[.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 "rcNN".
  *
  *    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/
  */
 
 /*
  * Y2K compliance in libpng:
  * =========================
  *
- *    December 17, 2015
+ *    May 26, 2016
  *
  *    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 1.2.56 are Y2K compliant.  It is my belief that earlier
- *    versions were also Y2K compliant.
+ *    upward through 1.6.22 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.
+ *    Libpng only has two year fields.  One is a 2-byte unsigned integer
+ *    that will hold years up to 65535.  The other, which is deprecated,
+ *    holds the date in text format, and will hold years up to 9999.
  *
  *    The integer is
  *        "png_uint_16 year" in png_time_struct.
  *
- *    The strings are
- *        "png_charp time_buffer" in png_struct and
- *        "near_time_buffer", which is a local character string in png.c.
+ *    The string is
+ *        "char time_buffer[29]" in png_struct.  This is no longer used
+ *    in libpng-1.6.x and will be removed from libpng-1.7.0.
  *
  *    There are seven time-related functions:
- *        png.c: png_convert_to_rfc_1123() in png.c
- *          (formerly png_convert_to_rfc_1152() in error)
+ *        png.c: png_convert_to_rfc_1123_buffer() in png.c
+ *          (formerly png_convert_to_rfc_1123() prior to libpng-1.5.x and
+ *          png_convert_to_rfc_1152() in error prior to libpng-0.98)
  *        png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
  *        png_convert_from_time_t() in pngwrite.c
  *        png_get_tIME() in pngget.c
  *        png_handle_tIME() in pngrutil.c, called in pngread.c
  *        png_set_tIME() in pngset.c
  *        png_write_tIME() in pngwutil.c, called in pngwrite.c
  *
  *    All handle dates properly in a Y2K environment.  The
  *    png_convert_from_time_t() function calls gmtime() to convert from system
  *    clock time, which returns (year - 1900), which we properly convert to
- *    the full 4-digit year.  There is a possibility that applications using
- *    libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
+ *    the full 4-digit year.  There is a possibility that libpng applications
+ *    are not passing 4-digit years into the png_convert_to_rfc_1123_buffer()
  *    function, or that they are incorrectly passing only a 2-digit year
  *    instead of "year - 1900" into the png_convert_from_struct_tm() function,
  *    but this is not under our control.  The libpng documentation has always
  *    stated that it works with 4-digit years, and the APIs have been
  *    documented as such.
  *
  *    The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
  *    integer to hold the year, and can hold years as large as 65535.
  *
  *    zlib, upon which libpng depends, is also Y2K compliant.  It contains
  *    no date-related code.
  *
  *       Glenn Randers-Pehrson
  *       libpng maintainer
  *       PNG Development Group
  */
 
 #ifndef PNG_H
 #define PNG_H
 
-/* This is not the place to learn how to use libpng.  The file libpng.txt
+/* This is not the place to learn how to use libpng. The file libpng-manual.txt
  * describes how to use libpng, and the file example.c summarizes it
  * with some code on which to build.  This file is useful for looking
- * at the actual function definitions and structure components.
+ * at the actual function definitions and structure components.  If that
+ * file has been stripped from your copy of libpng, you can find it at
+ * <http://www.libpng.org/pub/png/libpng-manual.txt>
+ *
+ * If you just need to read a PNG file and don't want to read the documentation
+ * skip to the end of this file and read the section entitled 'simplified API'.
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.2.56"
+#define PNG_LIBPNG_VER_STRING "1.6.22"
 #define PNG_HEADER_VERSION_STRING \
-   " libpng version 1.2.56 - December 17, 2015\n"
+     " libpng version 1.6.22 - May 26, 2016\n"
 
-#define PNG_LIBPNG_VER_SONUM   0
-#define PNG_LIBPNG_VER_DLLNUM  13
+#define PNG_LIBPNG_VER_SONUM   16
+#define PNG_LIBPNG_VER_DLLNUM  16
 
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
-#define PNG_LIBPNG_VER_MINOR   2
-#define PNG_LIBPNG_VER_RELEASE 56
+#define PNG_LIBPNG_VER_MINOR   6
+#define PNG_LIBPNG_VER_RELEASE 22
+
 /* 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_STABLE
 
 /* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
  * We must not include leading zeros.
  * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
  * version 1.0.0 was mis-numbered 100 instead of 10000).  From
  * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release
  */
-#define PNG_LIBPNG_VER 10256 /* 1.2.56 */
+#define PNG_LIBPNG_VER 10622 /* 1.6.22 */
+
+/* Library configuration: these options cannot be changed after
+ * the library has been built.
+ */
+#ifndef PNGLCONF_H
+    /* If pnglibconf.h is missing, you can
+     * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
+     */
+#   include "pnglibconf.h"
+#endif
 
 #ifndef PNG_VERSION_INFO_ONLY
-/* Include the compression library's header */
-#include "zlib.h"
+   /* Machine specific configuration. */
+#  include "pngconf.h"
 #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
+ * 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
+#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
 #  define PNG_LIBPNG_BUILD_TYPE \
-          (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
+       (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)
+         (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.
- */
-
-#ifndef PNG_NO_TYPECAST_NULL
-#define int_p_NULL                (int *)NULL
-#define png_bytep_NULL            (png_bytep)NULL
-#define png_bytepp_NULL           (png_bytepp)NULL
-#define png_doublep_NULL          (png_doublep)NULL
-#define png_error_ptr_NULL        (png_error_ptr)NULL
-#define png_flush_ptr_NULL        (png_flush_ptr)NULL
-#define png_free_ptr_NULL         (png_free_ptr)NULL
-#define png_infopp_NULL           (png_infopp)NULL
-#define png_malloc_ptr_NULL       (png_malloc_ptr)NULL
-#define png_read_status_ptr_NULL  (png_read_status_ptr)NULL
-#define png_rw_ptr_NULL           (png_rw_ptr)NULL
-#define png_structp_NULL          (png_structp)NULL
-#define png_uint_16p_NULL         (png_uint_16p)NULL
-#define png_voidp_NULL            (png_voidp)NULL
-#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
-#else
-#define int_p_NULL                NULL
-#define png_bytep_NULL            NULL
-#define png_bytepp_NULL           NULL
-#define png_doublep_NULL          NULL
-#define png_error_ptr_NULL        NULL
-#define png_flush_ptr_NULL        NULL
-#define png_free_ptr_NULL         NULL
-#define png_infopp_NULL           NULL
-#define png_malloc_ptr_NULL       NULL
-#define png_read_status_ptr_NULL  NULL
-#define png_rw_ptr_NULL           NULL
-#define png_structp_NULL          NULL
-#define png_uint_16p_NULL         NULL
-#define png_voidp_NULL            NULL
-#define png_write_status_ptr_NULL NULL
-#endif
-
-/* 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.
  */
-#ifdef PNG_USE_GLOBAL_ARRAYS
-PNG_EXPORT_VAR (PNG_CONST char) png_libpng_ver[18];
-  /* Need room for 99.99.99beta99z */
-#else
 #define png_libpng_ver png_get_header_ver(NULL)
-#endif
 
-#ifdef PNG_USE_GLOBAL_ARRAYS
-/* This was removed in version 1.0.5c */
-/* Structures to facilitate easy interlacing.  See png.c for more details */
-PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_start[7];
-PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_inc[7];
-PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_ystart[7];
-PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_yinc[7];
-PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_mask[7];
-PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_dsp_mask[7];
-/* This isn't currently used.  If you need it, see png.c for more details.
-PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_height[7];
-*/
-#endif
+/* This file is arranged in several sections:
+ *
+ * 1. [omitted]
+ * 2. Any configuration options that can be specified by for the application
+ *    code when it is built.  (Build time configuration is in pnglibconf.h)
+ * 3. Type definitions (base types are defined in pngconf.h), structure
+ *    definitions.
+ * 4. Exported library functions.
+ * 5. Simplified API.
+ * 6. Implementation options.
+ *
+ * The library source code has additional files (principally pngpriv.h) that
+ * allow configuration of the library.
+ */
 
-#endif /* PNG_NO_EXTERN */
+/* Section 1: [omitted] */
+
+/* Section 2: run time configuration
+ * See pnglibconf.h for build time configuration
+ *
+ * Run time configuration allows the application to choose between
+ * implementations of certain arithmetic APIs.  The default is set
+ * at build time and recorded in pnglibconf.h, but it is safe to
+ * override these (and only these) settings.  Note that this won't
+ * change what the library does, only application code, and the
+ * settings can (and probably should) be made on a per-file basis
+ * by setting the #defines before including png.h
+ *
+ * Use macros to read integers from PNG data or use the exported
+ * functions?
+ *   PNG_USE_READ_MACROS: use the macros (see below)  Note that
+ *     the macros evaluate their argument multiple times.
+ *   PNG_NO_USE_READ_MACROS: call the relevant library function.
+ *
+ * Use the alternative algorithm for compositing alpha samples that
+ * does not use division?
+ *   PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division'
+ *      algorithm.
+ *   PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm.
+ *
+ * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is
+ * false?
+ *   PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error
+ *      APIs to png_warning.
+ * Otherwise the calls are mapped to png_error.
+ */
+
+/* Section 3: type definitions, including structures and compile time
+ * constants.
+ * See pngconf.h for base types that vary by machine/system
+ */
+
+/* This triggers a compiler error in png.c, if png.c and png.h
+ * do not agree upon the version number.
+ */
+typedef char* png_libpng_version_1_6_22;
+
+/* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
+ *
+ * png_struct is the cache of information used while reading or writing a single
+ * PNG file.  One of these is always required, although the simplified API
+ * (below) hides the creation and destruction of it.
+ */
+typedef struct png_struct_def png_struct;
+typedef const png_struct * png_const_structp;
+typedef png_struct * png_structp;
+typedef png_struct * * png_structpp;
+
+/* png_info contains information read from or to be written to a PNG file.  One
+ * or more of these must exist while reading or creating a PNG file.  The
+ * information is not used by libpng during read but is used to control what
+ * gets written when a PNG file is created.  "png_get_" function calls read
+ * information during read and "png_set_" functions calls write information
+ * when creating a PNG.
+ * been moved into a separate header file that is not accessible to
+ * applications.  Read libpng-manual.txt or libpng.3 for more info.
+ */
+typedef struct png_info_def png_info;
+typedef png_info * png_infop;
+typedef const png_info * png_const_infop;
+typedef png_info * * png_infopp;
+
+/* Types with names ending 'p' are pointer types.  The corresponding types with
+ * names ending 'rp' are identical pointer types except that the pointer is
+ * marked 'restrict', which means that it is the only pointer to the object
+ * passed to the function.  Applications should not use the 'restrict' types;
+ * it is always valid to pass 'p' to a pointer with a function argument of the
+ * corresponding 'rp' type.  Different compilers have different rules with
+ * regard to type matching in the presence of 'restrict'.  For backward
+ * compatibility libpng callbacks never have 'restrict' in their parameters and,
+ * consequentially, writing portable application code is extremely difficult if
+ * an attempt is made to use 'restrict'.
+ */
+typedef png_struct * PNG_RESTRICT png_structrp;
+typedef const png_struct * PNG_RESTRICT png_const_structrp;
+typedef png_info * PNG_RESTRICT png_inforp;
+typedef const png_info * PNG_RESTRICT png_const_inforp;
 
 /* Three color definitions.  The order of the red, green, and blue, (and the
  * exact size) is not important, although the size of the fields need to
  * 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 png_color * png_colorp;
+typedef const png_color * png_const_colorp;
+typedef png_color * * 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 png_color_16 * png_color_16p;
+typedef const png_color_16 * png_const_color_16p;
+typedef png_color_16 * * png_color_16pp;
 
 typedef struct png_color_8_struct
 {
    png_byte 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;
+typedef png_color_8 * png_color_8p;
+typedef const png_color_8 * png_const_color_8p;
+typedef png_color_8 * * 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;
+typedef png_sPLT_entry * png_sPLT_entryp;
+typedef const png_sPLT_entry * png_const_sPLT_entryp;
+typedef png_sPLT_entry * * png_sPLT_entrypp;
 
 /*  When the depth of the sPLT palette is 8 bits, the color and alpha samples
  *  occupy the LSB of their respective members, and the MSB of each member
  *  is zero-filled.  The frequency member always occupies the full 16 bits.
  */
 
 typedef struct png_sPLT_struct
 {
    png_charp name;           /* palette name */
    png_byte depth;           /* depth of palette samples */
    png_sPLT_entryp entries;  /* palette entries */
    png_int_32 nentries;      /* number of palette entries */
 } png_sPLT_t;
-typedef png_sPLT_t FAR * png_sPLT_tp;
-typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
+typedef png_sPLT_t * png_sPLT_tp;
+typedef const png_sPLT_t * png_const_sPLT_tp;
+typedef png_sPLT_t * * png_sPLT_tpp;
 
 #ifdef PNG_TEXT_SUPPORTED
 /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
  * and whether that contents is compressed or not.  The "key" field
- * points to a regular zero-terminated C string.  The "text", "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.
+ * points to a regular zero-terminated C string.  The "text" fields can be a
+ * regular C string, an empty string, or a NULL pointer.
+ * However, the structure returned by png_get_text() will always contain
+ * the "text" field as a regular zero-terminated C string (possibly
+ * empty), never a NULL pointer, so it can be safely used in printf() and
+ * other string-handling functions.  Note that the "itxt_length", "lang", and
+ * "lang_key" members of the structure only exist when the library is built
+ * with iTXt chunk support.  Prior to libpng-1.4.0 the library was built by
+ * default without iTXt support. Also note that when iTXt *is* supported,
+ * the "lang" and "lang_key" fields contain NULL pointers when the
+ * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or
+ * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the
+ * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"
+ * which is always 0 or 1, or its "compression method" which is always 0.
  */
 typedef struct png_text_struct
 {
    int  compression;       /* compression value:
                              -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;
+typedef png_text * png_textp;
+typedef const png_text * png_const_textp;
+typedef png_text * * png_textpp;
 #endif
 
 /* Supported compression types for text in PNG files (tEXt, and zTXt).
- * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed.
- */
+ * 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;
+typedef png_time * png_timep;
+typedef const png_time * png_const_timep;
+typedef png_time * * png_timepp;
 
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
- defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
+#if defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) ||\
+   defined(PNG_USER_CHUNKS_SUPPORTED)
 /* png_unknown_chunk is a structure to hold queued chunks for which there is
  * no specific support.  The idea is that we can use this to queue
  * up private chunks for output even though the library doesn't actually
  * know about their semantics.
+ *
+ * The data in the structure is set by libpng on read and used on write.
  */
-#define PNG_CHUNK_NAME_LENGTH 5
 typedef struct png_unknown_chunk_t
 {
-    png_byte name[PNG_CHUNK_NAME_LENGTH];
-    png_byte *data;
+    png_byte name[5]; /* Textual chunk name with '\0' terminator */
+    png_byte *data;   /* Data, should not be modified on read! */
     png_size_t size;
 
-    /* libpng-using applications should NOT directly modify this byte. */
+    /* On write 'location' must be set using the flag values listed below.
+     * Notice that on read it is set by libpng however the values stored have
+     * more bits set than are listed below.  Always treat the value as a
+     * bitmask.  On write set only one bit - setting multiple bits may cause the
+     * chunk to be written in multiple places.
+     */
     png_byte location; /* mode of operation at read time */
 }
 png_unknown_chunk;
-typedef png_unknown_chunk FAR * png_unknown_chunkp;
-typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
+
+typedef png_unknown_chunk * png_unknown_chunkp;
+typedef const png_unknown_chunk * png_const_unknown_chunkp;
+typedef png_unknown_chunk * * 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_uint_32 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 PNG_DEPSTRUCT; /* transparent values for paletted image */
-   png_color_16 trans_values 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 */
-#ifdef PNG_FREE_ME_SUPPORTED
-   png_uint_32 free_me PNG_DEPSTRUCT;     /* flags items libpng is responsible for freeing */
-#endif
-
-#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;
+/* Flag values for the unknown chunk location byte. */
+#define PNG_HAVE_IHDR  0x01
+#define PNG_HAVE_PLTE  0x02
+#define PNG_AFTER_IDAT 0x08
 
 /* Maximum positive integer used in PNG is (2^31)-1 */
 #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
 #define PNG_UINT_32_MAX ((png_uint_32)(-1))
 #define PNG_SIZE_MAX ((png_size_t)(-1))
-#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
-/* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
-#define PNG_MAX_UINT PNG_UINT_31_MAX
-#endif
+
+/* These are constants for fixed point values encoded in the
+ * PNG specification manner (x100000)
+ */
+#define PNG_FP_1    100000
+#define PNG_FP_HALF  50000
+#define PNG_FP_MAX  ((png_fixed_point)0x7fffffffL)
+#define PNG_FP_MIN  (-PNG_FP_MAX)
 
 /* These describe the color_type field in png_info. */
 /* color type masks */
 #define PNG_COLOR_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)
@@ skipping 52 matching lines @@
 #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 */
+#define PNG_INFO_gAMA 0x0001U
+#define PNG_INFO_sBIT 0x0002U
+#define PNG_INFO_cHRM 0x0004U
+#define PNG_INFO_PLTE 0x0008U
+#define PNG_INFO_tRNS 0x0010U
+#define PNG_INFO_bKGD 0x0020U
+#define PNG_INFO_hIST 0x0040U
+#define PNG_INFO_pHYs 0x0080U
+#define PNG_INFO_oFFs 0x0100U
+#define PNG_INFO_tIME 0x0200U
+#define PNG_INFO_pCAL 0x0400U
+#define PNG_INFO_sRGB 0x0800U  /* GR-P, 0.96a */
+#define PNG_INFO_iCCP 0x1000U  /* ESR, 1.0.6 */
+#define PNG_INFO_sPLT 0x2000U  /* ESR, 1.0.6 */
+#define PNG_INFO_sCAL 0x4000U  /* ESR, 1.0.6 */
+#define PNG_INFO_IDAT 0x8000U  /* 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_uint_32 rowbytes; /* number of bytes in row */
-   png_byte color_type; /* color type of row */
-   png_byte bit_depth; /* bit depth of row */
-   png_byte channels; /* number of channels (1, 2, 3, or 4) */
+   png_uint_32 width;    /* width of row */
+   png_size_t rowbytes;  /* number of bytes in row */
+   png_byte color_type;  /* color type of row */
+   png_byte bit_depth;   /* bit depth of row */
+   png_byte channels;    /* number of channels (1, 2, 3, or 4) */
    png_byte pixel_depth; /* bits per pixel (depth * channels) */
 } png_row_info;
 
-typedef png_row_info FAR * png_row_infop;
-typedef png_row_info FAR * FAR * png_row_infopp;
+typedef png_row_info * png_row_infop;
+typedef png_row_info * * png_row_infopp;
 
 /* These are the function types for the I/O functions and for the functions
  * that allow the user to override the default I/O functions with his or her
  * own.  The png_error_ptr type should match that of user-supplied warning
  * and error functions, while the png_rw_ptr type should match that of the
- * user read/write data functions.
+ * user read/write data functions.  Note that the 'write' function must not
+ * modify the buffer it is passed. The 'read' function, on the other hand, is
+ * expected to return the read data in the buffer.
  */
-typedef struct png_struct_def png_struct;
-typedef png_struct FAR * png_structp;
-
-typedef 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));
+typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp));
+typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t));
+typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp));
+typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32,
+    int));
+typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32,
+    int));
 
 #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));
+typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));
+typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));
+
+/* The following callback receives png_uint_32 row_number, int pass for the
+ * png_bytep data of the row.  When transforming an interlaced image the
+ * row number is the row number within the sub-image of the interlace pass, so
+ * the value will increase to the height of the sub-image (not the full image)
+ * then reset to 0 for the next pass.
+ *
+ * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+ * find the output pixel (x,y) given an interlaced sub-image pixel
+ * (row,col,pass).  (See below for these macros.)
+ */
+typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,
+    png_uint_32, int));
 #endif
 
 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_LEGACY_SUPPORTED)
-typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
-    png_row_infop, png_bytep));
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+typedef PNG_CALLBACK(void, *png_user_transform_ptr, (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));
+typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
+    png_unknown_chunkp));
 #endif
 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
+/* not used anywhere */
+/* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (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.  The
+ * function is required to be PNG_NORETURN, but this is not checked.  If the
+ * function does return the application will crash via an abort() or similar
+ * system level call.
+ *
+ * If you get a warning here while building the library you may need to make
+ * changes to ensure that pnglibconf.h records the calling convention used by
+ * your compiler.  This may be very difficult - try using a different compiler
+ * to build the library!
+ */
+PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);
 #endif
 
 /* Transform masks for the high-level interface */
 #define PNG_TRANSFORM_IDENTITY       0x0000    /* read and write */
 #define PNG_TRANSFORM_STRIP_16       0x0001    /* read only */
 #define PNG_TRANSFORM_STRIP_ALPHA    0x0002    /* read only */
 #define PNG_TRANSFORM_PACKING        0x0004    /* read and write */
 #define PNG_TRANSFORM_PACKSWAP       0x0008    /* read and write */
 #define PNG_TRANSFORM_EXPAND         0x0010    /* read only */
 #define PNG_TRANSFORM_INVERT_MONO    0x0020    /* read and write */
 #define PNG_TRANSFORM_SHIFT          0x0040    /* read and write */
 #define PNG_TRANSFORM_BGR            0x0080    /* read and write */
 #define PNG_TRANSFORM_SWAP_ALPHA     0x0100    /* read and write */
 #define PNG_TRANSFORM_SWAP_ENDIAN    0x0200    /* read and write */
 #define PNG_TRANSFORM_INVERT_ALPHA   0x0400    /* read and write */
-#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* write only, deprecated */
+#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* write only */
 /* Added to libpng-1.2.34 */
-#define PNG_TRANSFORM_STRIP_FILLER_BEFORE 0x0800  /* write only */
-#define PNG_TRANSFORM_STRIP_FILLER_AFTER  0x1000  /* write only */
-/* Added to libpng-1.2.41 */
+#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
+#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
+/* Added to libpng-1.4.0 */
 #define PNG_TRANSFORM_GRAY_TO_RGB   0x2000      /* read only */
+/* Added to libpng-1.5.4 */
+#define PNG_TRANSFORM_EXPAND_16     0x4000      /* read only */
+#if INT_MAX >= 0x8000 /* else this might break */
+#define PNG_TRANSFORM_SCALE_16      0x8000      /* read only */
+#endif
 
 /* 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_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;            /* used in png_error */
-#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_uint_32 rowbytes PNG_DEPSTRUCT;      /* size of row in bytes */
-#if 0 /* Replaced with the following in libpng-1.2.43 */
-   png_size_t irowbytes PNG_DEPSTRUCT;
-#endif
-/* Added in libpng-1.2.43 */
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown
-    * chunks that can be stored (0 means unlimited).
-    */
-   png_uint_32 user_chunk_cache_max PNG_DEPSTRUCT;
-#endif
-   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 */
-#ifndef PNG_NO_WRITE_FILTER
-   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 */
-#endif
-   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)
-#ifdef PNG_LEGACY_SUPPORTED
-   png_byte filler PNG_DEPSTRUCT;           /* filler byte for pixel expansion */
-#else
-   png_uint_16 filler PNG_DEPSTRUCT;           /* filler bytes for pixel expansion */
-#endif
-#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 PNG_DEPSTRUCT;           /* transparency values for paletted files */
-   png_color_16 trans_values PNG_DEPSTRUCT; /* transparency values 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_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_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 */
-
-#ifdef PNG_FREE_ME_SUPPORTED
-   png_uint_32 free_me PNG_DEPSTRUCT;   /* flags items libpng is responsible for freeing */
-#endif
-
-#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 */
-#ifdef PNG_1_0_X
-   png_byte mng_features_permitted PNG_DEPSTRUCT;
-#else
-   png_uint_32 mng_features_permitted PNG_DEPSTRUCT;
-#endif /* PNG_1_0_X */
-#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
-
-#ifdef PNG_1_0_X
-/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
-   png_uint_32 row_buf_size PNG_DEPSTRUCT;
-#endif
-
-/* New members added in libpng-1.2.0 */
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-#  ifndef PNG_1_0_X
-#    ifdef PNG_MMX_CODE_SUPPORTED
-   png_byte     mmx_bitdepth_threshold PNG_DEPSTRUCT;
-   png_uint_32  mmx_rowbytes_threshold PNG_DEPSTRUCT;
-#    endif
-   png_uint_32  asm_flags PNG_DEPSTRUCT;
-#  endif
-#endif
-
-/* 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_USER_LIMITS_SUPPORTED
-   png_uint_32 user_width_max PNG_DEPSTRUCT;
-   png_uint_32 user_height_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 */
-
-
-};
-
-
-/* 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_2_56;
-
-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
+/* NOTE: prior to 1.5 these functions had no 'API' style declaration,
+ * this allowed the zlib default functions to be used on Windows
+ * platforms.  In 1.5 the zlib default malloc (which just calls malloc and
+ * ignores the first argument) should be completely compatible with the
+ * following.
+ */
+typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp,
+    png_alloc_size_t));
+typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp));
+
+/* Section 4: exported functions
+ * Here are the function definitions most commonly used.  This is not
+ * the place to find out how to use libpng.  See libpng-manual.txt for the
  * full explanation, see example.c for the summary.  This just provides
  * a simple one line description of the use of each function.
+ *
+ * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in
+ * pngconf.h and in the *.dfn files in the scripts directory.
+ *
+ *   PNG_EXPORT(ordinal, type, name, (args));
+ *
+ *       ordinal:    ordinal that is used while building
+ *                   *.def files. The ordinal value is only
+ *                   relevant when preprocessing png.h with
+ *                   the *.dfn files for building symbol table
+ *                   entries, and are removed by pngconf.h.
+ *       type:       return type of the function
+ *       name:       function name
+ *       args:       function arguments, with types
+ *
+ * When we wish to append attributes to a function prototype we use
+ * the PNG_EXPORTA() macro instead.
+ *
+ *   PNG_EXPORTA(ordinal, type, name, (args), attributes);
+ *
+ *       ordinal, type, name, and args: same as in PNG_EXPORT().
+ *       attributes: function attributes
  */
 
 /* Returns the version number of the library */
-extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
+PNG_EXPORT(1, png_uint_32, png_access_version_number, (void));
 
 /* Tell lib we have already handled the first <num_bytes> magic bytes.
  * Handling more than 8 bytes from the beginning of the file is an error.
  */
-extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
-   int num_bytes));
+PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes));
 
 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
  * PNG file.  Returns zero if the supplied bytes match the 8-byte PNG
  * signature, and non-zero otherwise.  Having num_to_check == 0 or
  * start > 7 will always fail (ie return non-zero).
  */
-extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
-   png_size_t num_to_check));
+PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start,
+    png_size_t num_to_check));
 
 /* Simple signature checking function.  This is the same as calling
  * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
  */
-extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num)) PNG_DEPRECATED;
+#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n))
 
 /* Allocate and initialize png_ptr struct for reading, and any other memory. */
-extern PNG_EXPORT(png_structp,png_create_read_struct)
-   PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
-   png_error_ptr error_fn, png_error_ptr warn_fn)) PNG_ALLOCATED;
+PNG_EXPORTA(4, png_structp, png_create_read_struct,
+    (png_const_charp user_png_ver, png_voidp error_ptr,
+    png_error_ptr error_fn, png_error_ptr warn_fn),
+    PNG_ALLOCATED);
 
 /* Allocate and initialize png_ptr struct for writing, and any other memory */
-extern PNG_EXPORT(png_structp,png_create_write_struct)
-   PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
-   png_error_ptr error_fn, png_error_ptr warn_fn)) PNG_ALLOCATED;
-
-#ifdef PNG_WRITE_SUPPORTED
-extern PNG_EXPORT(png_uint_32,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_uint_32 size));
-#endif
-
+PNG_EXPORTA(5, png_structp, png_create_write_struct,
+    (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
+    png_error_ptr warn_fn),
+    PNG_ALLOCATED);
+
+PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size,
+    (png_const_structrp png_ptr));
+
+PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr,
+    png_size_t size));
+
+/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp
+ * match up.
+ */
+#ifdef PNG_SETJMP_SUPPORTED
+/* This function returns the jmp_buf built in to *png_ptr.  It must be
+ * supplied with an appropriate 'longjmp' function to use on that jmp_buf
+ * unless the default error function is overridden in which case NULL is
+ * acceptable.  The size of the jmp_buf is checked against the actual size
+ * allocated by the library - the call will return NULL on a mismatch
+ * indicating an ABI mismatch.
+ */
+PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr,
+    png_longjmp_ptr longjmp_fn, size_t jmp_buf_size));
+#  define png_jmpbuf(png_ptr) \
+      (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf))))
+#else
+#  define png_jmpbuf(png_ptr) \
+      (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
+#endif
+/* This function should be used by libpng applications in place of
+ * longjmp(png_ptr->jmpbuf, val).  If longjmp_fn() has been set, it
+ * will use it; otherwise it will call PNG_ABORT().  This function was
+ * added in libpng-1.5.0.
+ */
+PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val),
+    PNG_NORETURN);
+
+#ifdef PNG_READ_SUPPORTED
 /* Reset the compression stream */
-extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
+PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED);
+#endif
 
 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
 #ifdef PNG_USER_MEM_SUPPORTED
-extern PNG_EXPORT(png_structp,png_create_read_struct_2)
-   PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
-   png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
-   png_malloc_ptr malloc_fn, png_free_ptr free_fn)) 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
+PNG_EXPORTA(11, png_structp, png_create_read_struct_2,
+    (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
+    png_error_ptr warn_fn,
+    png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
+    PNG_ALLOCATED);
+PNG_EXPORTA(12, png_structp, png_create_write_struct_2,
+    (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
+    png_error_ptr warn_fn,
+    png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
+    PNG_ALLOCATED);
+#endif
+
+/* Write the PNG file signature. */
+PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr));
 
 /* Write a PNG chunk - size, type, (optional) data, CRC. */
-extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
-   png_bytep chunk_name, png_bytep data, png_size_t length));
+PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep
+    chunk_name, png_const_bytep data, png_size_t length));
 
 /* Write the start of a PNG chunk - length and chunk name. */
-extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
-   png_bytep chunk_name, png_uint_32 length));
+PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr,
+    png_const_bytep chunk_name, png_uint_32 length));
 
 /* Write the data of a PNG chunk started with png_write_chunk_start(). */
-extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
-   png_bytep data, png_size_t length));
+PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr,
+    png_const_bytep data, png_size_t length));
 
 /* Finish a chunk started with png_write_chunk_start() (includes CRC). */
-extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
+PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr));
 
 /* Allocate and initialize the info structure */
-extern PNG_EXPORT(png_infop,png_create_info_struct)
-   PNGARG((png_structp png_ptr)) PNG_ALLOCATED;
-
-#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
-/* Initialize the info structure (old interface - DEPRECATED) */
-extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr))
-    PNG_DEPRECATED;
-#undef png_info_init
-#define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
-    png_sizeof(png_info));
-#endif
-
-extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
-    png_size_t png_info_struct_size));
+PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr),
+    PNG_ALLOCATED);
+
+/* DEPRECATED: this function allowed init structures to be created using the
+ * default allocation method (typically malloc).  Use is deprecated in 1.6.0 and
+ * the API will be removed in the future.
+ */
+PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr,
+    png_size_t png_info_struct_size), PNG_DEPRECATED);
 
 /* Writes all the PNG information before the image. */
-extern PNG_EXPORT(void,png_write_info_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));
+PNG_EXPORT(20, void, png_write_info_before_PLTE,
+    (png_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(21, void, png_write_info,
+    (png_structrp png_ptr, png_const_inforp info_ptr));
 
 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 /* Read the information before the actual image data. */
-extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
-   png_infop info_ptr));
+PNG_EXPORT(22, void, png_read_info,
+    (png_structrp png_ptr, png_inforp 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));
+   /* Convert to a US string format: there is no localization support in this
+    * routine.  The original implementation used a 29 character buffer in
+    * png_struct, this will be removed in future versions.
+    */
+#if PNG_LIBPNG_VER < 10700
+/* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */
+PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr,
+    png_const_timep ptime),PNG_DEPRECATED);
+#endif
+PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29],
+    png_const_timep ptime));
 #endif
 
 #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));
+PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,
+    const struct tm * 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 */
+PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime));
+#endif /* CONVERT_tIME */
 
 #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));
-#ifndef PNG_1_0_X
-extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp
-  png_ptr));
-#endif
-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));
-#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
-/* Deprecated */
-extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp
-    png_ptr)) PNG_DEPRECATED;
-#endif
+PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr));
+PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr));
+PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr));
+PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr));
+#endif
+
+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion
+ * of a tRNS chunk if present.
+ */
+PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr));
 #endif
 
 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
 /* Use blue, green, red order for pixels. */
-extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
+PNG_EXPORT(30, void, png_set_bgr, (png_structrp 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));
+PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp 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));
+#define PNG_ERROR_ACTION_NONE  1
+#define PNG_ERROR_ACTION_WARN  2
+#define PNG_ERROR_ACTION_ERROR 3
+#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/
+
+PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr,
+    int error_action, double red, double green))
+PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr,
+    int error_action, png_fixed_point red, png_fixed_point green))
+
+PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp
+    png_ptr));
+#endif
+
+#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
+PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
+    png_colorp palette));
+#endif
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+/* How the alpha channel is interpreted - this affects how the color channels
+ * of a PNG file are returned to the calling application when an alpha channel,
+ * or a tRNS chunk in a palette file, is present.
+ *
+ * This has no effect on the way pixels are written into a PNG output
+ * datastream. The color samples in a PNG datastream are never premultiplied
+ * with the alpha samples.
+ *
+ * The default is to return data according to the PNG specification: the alpha
+ * channel is a linear measure of the contribution of the pixel to the
+ * corresponding composited pixel, and the color channels are unassociated
+ * (not premultiplied).  The gamma encoded color channels must be scaled
+ * according to the contribution and to do this it is necessary to undo
+ * the encoding, scale the color values, perform the composition and reencode
+ * the values.  This is the 'PNG' mode.
+ *
+ * The alternative is to 'associate' the alpha with the color information by
+ * storing color channel values that have been scaled by the alpha.
+ * image.  These are the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' modes
+ * (the latter being the two common names for associated alpha color channels).
+ *
+ * For the 'OPTIMIZED' mode, a pixel is treated as opaque only if the alpha
+ * value is equal to the maximum value.
+ *
+ * The final choice is to gamma encode the alpha channel as well.  This is
+ * broken because, in practice, no implementation that uses this choice
+ * correctly undoes the encoding before handling alpha composition.  Use this
+ * choice only if other serious errors in the software or hardware you use
+ * mandate it; the typical serious error is for dark halos to appear around
+ * opaque areas of the composited PNG image because of arithmetic overflow.
+ *
+ * The API function png_set_alpha_mode specifies which of these choices to use
+ * with an enumerated 'mode' value and the gamma of the required output:
+ */
+#define PNG_ALPHA_PNG           0 /* according to the PNG standard */
+#define PNG_ALPHA_STANDARD      1 /* according to Porter/Duff */
+#define PNG_ALPHA_ASSOCIATED    1 /* as above; this is the normal practice */
+#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */
+#define PNG_ALPHA_OPTIMIZED     2 /* 'PNG' for opaque pixels, else 'STANDARD' */
+#define PNG_ALPHA_BROKEN        3 /* the alpha channel is gamma encoded */
+
+PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode,
+    double output_gamma))
+PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr,
+    int mode, png_fixed_point output_gamma))
+#endif
+
+#if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
+/* The output_gamma value is a screen gamma in libpng terminology: it expresses
+ * how to decode the output values, not how they are encoded.
+ */
+#define PNG_DEFAULT_sRGB -1       /* sRGB gamma and color space */
+#define PNG_GAMMA_MAC_18 -2       /* Old Mac '1.8' gamma and color space */
+#define PNG_GAMMA_sRGB   220000   /* Television standards--matches sRGB gamma */
+#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */
+#endif
+
+/* The following are examples of calls to png_set_alpha_mode to achieve the
+ * required overall gamma correction and, where necessary, alpha
+ * premultiplication.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ *    This is the default libpng handling of the alpha channel - it is not
+ *    pre-multiplied into the color components.  In addition the call states
+ *    that the output is for a sRGB system and causes all PNG files without gAMA
+ *    chunks to be assumed to be encoded using sRGB.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ *    In this case the output is assumed to be something like an sRGB conformant
+ *    display preceeded by a power-law lookup table of power 1.45.  This is how
+ *    early Mac systems behaved.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);
+ *    This is the classic Jim Blinn approach and will work in academic
+ *    environments where everything is done by the book.  It has the shortcoming
+ *    of assuming that input PNG data with no gamma information is linear - this
+ *    is unlikely to be correct unless the PNG files where generated locally.
+ *    Most of the time the output precision will be so low as to show
+ *    significant banding in dark areas of the image.
+ *
+ * png_set_expand_16(pp);
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);
+ *    This is a somewhat more realistic Jim Blinn inspired approach.  PNG files
+ *    are assumed to have the sRGB encoding if not marked with a gamma value and
+ *    the output is always 16 bits per component.  This permits accurate scaling
+ *    and processing of the data.  If you know that your input PNG files were
+ *    generated locally you might need to replace PNG_DEFAULT_sRGB with the
+ *    correct value for your system.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);
+ *    If you just need to composite the PNG image onto an existing background
+ *    and if you control the code that does this you can use the optimization
+ *    setting.  In this case you just copy completely opaque pixels to the
+ *    output.  For pixels that are not completely transparent (you just skip
+ *    those) you do the composition math using png_composite or png_composite_16
+ *    below then encode the resultant 8-bit or 16-bit values to match the output
+ *    encoding.
+ *
+ * Other cases
+ *    If neither the PNG nor the standard linear encoding work for you because
+ *    of the software or hardware you use then you have a big problem.  The PNG
+ *    case will probably result in halos around the image.  The linear encoding
+ *    will probably result in a washed out, too bright, image (it's actually too
+ *    contrasty.)  Try the ALPHA_OPTIMIZED mode above - this will probably
+ *    substantially reduce the halos.  Alternatively try:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);
+ *    This option will also reduce the halos, but there will be slight dark
+ *    halos round the opaque parts of the image where the background is light.
+ *    In the OPTIMIZED mode the halos will be light halos where the background
+ *    is dark.  Take your pick - the halos are unavoidable unless you can get
+ *    your hardware/software fixed!  (The OPTIMIZED approach is slightly
+ *    faster.)
+ *
+ * When the default gamma of PNG files doesn't match the output gamma.
+ *    If you have PNG files with no gamma information png_set_alpha_mode allows
+ *    you to provide a default gamma, but it also sets the ouput gamma to the
+ *    matching value.  If you know your PNG files have a gamma that doesn't
+ *    match the output you can take advantage of the fact that
+ *    png_set_alpha_mode always sets the output gamma but only sets the PNG
+ *    default if it is not already set:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ *    The first call sets both the default and the output gamma values, the
+ *    second call overrides the output gamma without changing the default.  This
+ *    is easier than achieving the same effect with png_set_gamma.  You must use
+ *    PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will
+ *    fire if more than one call to png_set_alpha_mode and png_set_background is
+ *    made in the same read operation, however multiple calls with PNG_ALPHA_PNG
+ *    are ignored.
+ */
 
 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
+PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr));
 #endif
 
 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
     defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
+PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr));
 #endif
 
 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
     defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
+PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr));
 #endif
 
 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
-/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
-extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
-   png_uint_32 filler, int flags));
+/* Add a filler byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */
+PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler,
+    int flags));
 /* The values of the PNG_FILLER_ defines should NOT be changed */
-#define PNG_FILLER_BEFORE 0
-#define PNG_FILLER_AFTER 1
-/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
-#ifndef PNG_1_0_X
-extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
-   png_uint_32 filler, int flags));
-#endif
-#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
+#  define PNG_FILLER_BEFORE 0
+#  define PNG_FILLER_AFTER 1
+/* Add an alpha byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */
+PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr,
+    png_uint_32 filler, int flags));
+#endif /* READ_FILLER || WRITE_FILLER */
 
 #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));
+PNG_EXPORT(41, void, png_set_swap, (png_structrp 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)
+PNG_EXPORT(42, void, png_set_packing, (png_structrp 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));
+PNG_EXPORT(43, void, png_set_packswap, (png_structrp 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));
+PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_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));
+/* Have the code handle the interlacing.  Returns the number of passes.
+ * MUST be called before png_read_update_info or png_start_read_image,
+ * otherwise it will not have the desired effect.  Note that it is still
+ * necessary to call png_read_row or png_read_rows png_get_image_height
+ * times for each pass.
+*/
+PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr));
 #endif
 
 #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));
+PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp 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
+/* Handle alpha and tRNS by replacing with a background color.  Prior to
+ * libpng-1.5.4 this API must not be called before the PNG file header has been
+ * read.  Doing so will result in unexpected behavior and possible warnings or
+ * errors if the PNG file contains a bKGD chunk.
+ */
+PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr,
+    png_const_color_16p background_color, int background_gamma_code,
+    int need_expand, double background_gamma))
+PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr,
+    png_const_color_16p background_color, int background_gamma_code,
+    int need_expand, png_fixed_point background_gamma))
+#endif
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+#  define PNG_BACKGROUND_GAMMA_UNKNOWN 0
+#  define PNG_BACKGROUND_GAMMA_SCREEN  1
+#  define PNG_BACKGROUND_GAMMA_FILE    2
+#  define PNG_BACKGROUND_GAMMA_UNIQUE  3
+#endif
+
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+/* Scale a 16-bit depth file down to 8-bit, accurately. */
+PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr));
+#endif
+
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
+#define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */
 /* Strip the second byte of information from a 16-bit depth file. */
-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));
+PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr));
+#endif
+
+#ifdef PNG_READ_QUANTIZE_SUPPORTED
+/* Turn on quantizing, and reduce the palette to the number of colors
+ * available.
+ */
+PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr,
+    png_colorp palette, int num_palette, int maximum_colors,
+    png_const_uint_16p histogram, int full_quantize));
 #endif
 
 #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
-
-#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
-#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
-    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
-/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
-/* Deprecated and will be removed.  Use png_permit_mng_features() instead. */
-extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
-   int empty_plte_permitted)) PNG_DEPRECATED;
-#endif
+/* The threshold on gamma processing is configurable but hard-wired into the
+ * library.  The following is the floating point variant.
+ */
+#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001)
+
+/* Handle gamma correction. Screen_gamma=(display_exponent).
+ * NOTE: this API simply sets the screen and file gamma values. It will
+ * therefore override the value for gamma in a PNG file if it is called after
+ * the file header has been read - use with care  - call before reading the PNG
+ * file for best results!
+ *
+ * These routines accept the same gamma values as png_set_alpha_mode (described
+ * above).  The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either
+ * API (floating point or fixed.)  Notice, however, that the 'file_gamma' value
+ * is the inverse of a 'screen gamma' value.
+ */
+PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr,
+    double screen_gamma, double override_file_gamma))
+PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr,
+    png_fixed_point screen_gamma, png_fixed_point override_file_gamma))
 #endif
 
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
 /* Set how many lines between output flushes - 0 for no flushing */
-extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
+PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows));
 /* Flush the current PNG output buffer */
-extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
+PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr));
 #endif
 
 /* Optional update palette with requested transformations */
-extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
+PNG_EXPORT(53, void, png_start_read_image, (png_structrp 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));
-
-#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr,
+    png_inforp 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
-
-#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row,
+    png_bytepp display_row, png_uint_32 num_rows));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 /* Read a row of data. */
-extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
-   png_bytep row,
-   png_bytep display_row));
-#endif
-
-#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row,
+    png_bytep display_row));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 /* Read the whole image into memory at once. */
-extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
-   png_bytepp image));
+PNG_EXPORT(57, void, png_read_image, (png_structrp 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));
+PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr,
+    png_const_bytep row));
+
+/* Write a few rows of image data: (*row) is not written; however, the type
+ * is declared as writeable to maintain compatibility with previous versions
+ * of libpng and to allow the 'display_row' array from read_rows to be passed
+ * unchanged to write_rows.
+ */
+PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row,
+    png_uint_32 num_rows));
 
 /* Write the image data */
-extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
-   png_bytepp image));
-
-/* Writes the end of the PNG file. */
-extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
-   png_infop info_ptr));
-
-#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image));
+
+/* Write the end of the PNG file. */
+PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr,
+    png_inforp info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 /* Read the end of the PNG file. */
-extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
-   png_infop info_ptr));
+PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp 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));
+PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp 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 all memory used by the read (old method - NOT DLL EXPORTED) */
-extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_infop end_info_ptr)) PNG_DEPRECATED;
+PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr,
+    png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
 
 /* Free any memory associated with the png_struct and the png_info_structs */
-extern PNG_EXPORT(void,png_destroy_write_struct)
-   PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
-
-/* Free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
-extern void png_write_destroy PNGARG((png_structp png_ptr)) PNG_DEPRECATED;
+PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr,
+    png_infopp info_ptr_ptr));
 
 /* Set the libpng method of handling chunk CRC errors */
-extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
-   int crit_action, int ancil_action));
-
-/* Values for png_set_crc_action() to say how to handle CRC errors in
+PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action,
+    int ancil_action));
+
+/* Values for png_set_crc_action() say how to handle CRC errors in
  * ancillary and critical chunks, and whether to use the data contained
  * therein.  Note that it is impossible to "discard" data in a critical
  * chunk.  For versions prior to 0.90, the action was always error/quit,
  * 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 */
 
+#ifdef PNG_WRITE_SUPPORTED
 /* 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));
+PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method,
+    int filters));
+#endif /* WRITE */
 
 /* 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)
+#define PNG_FAST_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP)
+#define PNG_ALL_FILTERS (PNG_FAST_FILTERS | 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
 
-#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* DEPRECATED */
-#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 */
+#ifdef PNG_WRITE_SUPPORTED
+#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* DEPRECATED */
+PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr,
+    int heuristic_method, int num_weights, png_const_doublep filter_weights,
+    png_const_doublep filter_costs))
+PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
+    (png_structrp png_ptr, int heuristic_method, int num_weights,
+    png_const_fixed_point_p filter_weights,
+    png_const_fixed_point_p filter_costs))
+#endif /* WRITE_WEIGHTED_FILTER */
 
 /* The following are no longer used and will be removed from libpng-1.7: */
 #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));
+#ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
+PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr,
+    int level));
 
-extern PNG_EXPORT(void,png_set_compression_mem_level)
-   PNGARG((png_structp png_ptr, int mem_level));
+PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr,
+    int mem_level));
 
-extern PNG_EXPORT(void,png_set_compression_strategy)
-   PNGARG((png_structp png_ptr, int strategy));
+PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr,
+    int strategy));
 
-extern PNG_EXPORT(void,png_set_compression_window_bits)
-   PNGARG((png_structp png_ptr, int window_bits));
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr,
+    int window_bits));
 
-extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
-   int method));
+PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr,
+    int method));
+#endif /* WRITE_CUSTOMIZE_COMPRESSION */
+
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+/* Also set zlib parameters for compressing non-IDAT chunks */
+PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr,
+    int level));
+
+PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr,
+    int mem_level));
+
+PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr,
+    int strategy));
+
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+PNG_EXPORT(225, void, png_set_text_compression_window_bits,
+    (png_structrp png_ptr, int window_bits));
+
+PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr,
+    int method));
+#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
+#endif /* WRITE */
 
 /* These next functions are called for input/output, memory, and error
  * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
  * and call standard C I/O routines such as fread(), fwrite(), and
  * fprintf().  These functions can be made to use other I/O routines
  * at run time for those applications that need to handle I/O in a
- * different manner by calling png_set_???_fn().  See libpng.txt for
+ * different manner by calling png_set_???_fn().  See libpng-manual.txt for
  * more information.
  */
 
 #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));
+PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp));
 #endif
 
 /* Replace the (error and abort), and warning functions with user
  * 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));
+PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr,
+    png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
 
 /* Return the user pointer associated with the error functions */
-extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
+PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr));
 
 /* Replace the default data output functions with a user supplied one(s).
  * If buffered output is not used, then output_flush_fn can be set to NULL.
  * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
  * output_flush_fn will be ignored (and thus can be NULL).
  * It is probably a mistake to use NULL for output_flush_fn if
  * write_data_fn is not also NULL unless you have built libpng with
  * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's
  * default flush function, which uses the standard *FILE structure, will
  * be used.
  */
-extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
-   png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
+PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr,
+    png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
 
 /* Replace the default data input function with a user supplied one. */
-extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
-   png_voidp io_ptr, png_rw_ptr read_data_fn));
+PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr,
+    png_rw_ptr read_data_fn));
 
 /* Return the user pointer associated with the I/O functions */
-extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
-
-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));
+PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr));
+
+PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr,
+    png_read_status_ptr read_row_fn));
+
+PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr,
+    png_write_status_ptr write_row_fn));
 
 #ifdef PNG_USER_MEM_SUPPORTED
 /* Replace the default memory allocation functions with user supplied one(s). */
-extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
-   png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr,
+    png_malloc_ptr malloc_fn, png_free_ptr free_fn));
 /* Return the user pointer associated with the memory functions */
-extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_LEGACY_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
-
-#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_LEGACY_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) || \
-    defined(PNG_LEGACY_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));
+PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr));
+#endif
+
+#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
+PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr,
+    png_user_transform_ptr read_user_transform_fn));
+#endif
+
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
+PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr,
+    png_user_transform_ptr write_user_transform_fn));
+#endif
+
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
+PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr,
+    png_voidp user_transform_ptr, int user_transform_depth,
+    int user_transform_channels));
 /* Return the user pointer associated with the user transform functions */
-extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
-   PNGARG((png_structp png_ptr));
+PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,
+    (png_const_structrp png_ptr));
+#endif
+
+#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
+/* Return information about the row currently being processed.  Note that these
+ * APIs do not fail but will return unexpected results if called outside a user
+ * transform callback.  Also note that when transforming an interlaced image the
+ * row number is the row number within the sub-image of the interlace pass, so
+ * the value will increase to the height of the sub-image (not the full image)
+ * then reset to 0 for the next pass.
+ *
+ * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+ * find the output pixel (x,y) given an interlaced sub-image pixel
+ * (row,col,pass).  (See below for these macros.)
+ */
+PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp));
+PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp));
+#endif
+
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+/* This callback is called only for *unknown* chunks.  If
+ * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known
+ * chunks to be treated as unknown, however in this case the callback must do
+ * any processing required by the chunk (e.g. by calling the appropriate
+ * png_set_ APIs.)
+ *
+ * There is no write support - on write, by default, all the chunks in the
+ * 'unknown' list are written in the specified position.
+ *
+ * The integer return from the callback function is interpreted thus:
+ *
+ * negative: An error occurred; png_chunk_error will be called.
+ *     zero: The chunk was not handled, the chunk will be saved. A critical
+ *           chunk will cause an error at this point unless it is to be saved.
+ * positive: The chunk was handled, libpng will ignore/discard it.
+ *
+ * See "INTERACTION WTIH USER CHUNK CALLBACKS" below for important notes about
+ * how this behavior will change in libpng 1.7
+ */
+PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr,
+    png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
 #endif
 
 #ifdef PNG_USER_CHUNKS_SUPPORTED
-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));
+PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr));
 #endif
 
 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
 /* Sets the function callbacks for the push reader, and a pointer to a
  * user-defined structure available to the callback functions.
  */
-extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
-   png_voidp progressive_ptr,
-   png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
-   png_progressive_end_ptr end_fn));
+PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr,
+    png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
+    png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn));
 
 /* Returns the user pointer associated with the push read functions */
-extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
-   PNGARG((png_structp png_ptr));
+PNG_EXPORT(91, png_voidp, png_get_progressive_ptr,
+    (png_const_structrp 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_uint_32 size)) PNG_ALLOCATED;
-
-#ifdef PNG_1_0_X
-#  define png_malloc_warn png_malloc
-#else
+PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr,
+    png_inforp info_ptr, png_bytep buffer, png_size_t buffer_size));
+
+/* A function which may be called *only* within png_process_data to stop the
+ * processing of any more data.  The function returns the number of bytes
+ * remaining, excluding any that libpng has cached internally.  A subsequent
+ * call to png_process_data must supply these bytes again.  If the argument
+ * 'save' is set to true the routine will first save all the pending data and
+ * will always return 0.
+ */
+PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structrp, int save));
+
+/* A function which may be called *only* outside (after) a call to
+ * png_process_data.  It returns the number of bytes of data to skip in the
+ * input.  Normally it will return 0, but if it returns a non-zero value the
+ * application must skip than number of bytes of input data and pass the
+ * following data to the next call to png_process_data.
+ */
+PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp));
+
+/* Function that combines rows.  'new_row' is a flag that should come from
+ * the callback and be non-NULL if anything needs to be done; the library
+ * stores its own version of the new data internally and ignores the passed
+ * in value.
+ */
+PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr,
+    png_bytep old_row, png_const_bytep new_row));
+#endif /* PROGRESSIVE_READ */
+
+PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr,
+    png_alloc_size_t size), PNG_ALLOCATED);
+/* Added at libpng version 1.4.0 */
+PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr,
+    png_alloc_size_t size), PNG_ALLOCATED);
+
 /* Added at libpng version 1.2.4 */
-extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
-   png_uint_32 size)) PNG_ALLOCATED;
-#endif
+PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr,
+    png_alloc_size_t size), PNG_ALLOCATED);
 
 /* Frees a pointer allocated by png_malloc() */
-extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
-
-#ifdef PNG_1_0_X
-/* Function to allocate memory for zlib. */
-extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
-   uInt size));
-
-/* Function to free memory for zlib */
-extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
-#endif
+PNG_EXPORT(97, void, png_free, (png_const_structrp 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));
-#ifdef PNG_FREE_ME_SUPPORTED
+PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr,
+    png_inforp 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));
-#endif
+ * by libpng or by the application; this works on the png_info structure passed
+ * in, it does not change the state for other png_info structures.
+ *
+ * It is unlikely that this function works correctly as of 1.6.0 and using it
+ * may result either in memory leaks or double free of allocated data.
+ */
+PNG_EXPORT(99, void, png_data_freer, (png_const_structrp png_ptr,
+    png_inforp 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 */
+#define PNG_FREE_HIST 0x0008U
+#define PNG_FREE_ICCP 0x0010U
+#define PNG_FREE_SPLT 0x0020U
+#define PNG_FREE_ROWS 0x0040U
+#define PNG_FREE_PCAL 0x0080U
+#define PNG_FREE_SCAL 0x0100U
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+#  define PNG_FREE_UNKN 0x0200U
+#endif
+/*      PNG_FREE_LIST 0x0400U   removed in 1.6.0 because it is ignored */
+#define PNG_FREE_PLTE 0x1000U
+#define PNG_FREE_TRNS 0x2000U
+#define PNG_FREE_TEXT 0x4000U
+#define PNG_FREE_ALL  0x7fffU
+#define PNG_FREE_MUL  0x4220U /* 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_uint_32 size)) PNG_ALLOCATED;
-extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
-   png_voidp ptr));
-#endif
-
-extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
-   png_voidp s1, png_voidp s2, png_uint_32 size)) PNG_DEPRECATED;
-
-extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
-   png_voidp s1, int value, png_uint_32 size)) PNG_DEPRECATED;
-
-#if defined(USE_FAR_KEYWORD)  /* memory model conversion function */
-extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
-   int check));
-#endif /* USE_FAR_KEYWORD */
-
-#ifndef PNG_NO_ERROR_TEXT
+PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr,
+    png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED);
+PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr,
+    png_voidp ptr), PNG_DEPRECATED);
+#endif
+
+#ifdef PNG_ERROR_TEXT_SUPPORTED
 /* Fatal error in PNG image of libpng - can't continue */
-extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
-   png_const_charp error_message)) PNG_NORETURN;
+PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr,
+    png_const_charp error_message), PNG_NORETURN);
 
 /* The same, but the chunk name is prepended to the error string. */
-extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
-   png_const_charp error_message)) PNG_NORETURN;
+PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr,
+    png_const_charp error_message), PNG_NORETURN);
+
 #else
 /* Fatal error in PNG image of libpng - can't continue */
-extern PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr)) PNG_NORETURN;
-#endif
-
-#ifndef PNG_NO_WARNINGS
+PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN);
+#  define png_error(s1,s2) png_err(s1)
+#  define png_chunk_error(s1,s2) png_err(s1)
+#endif
+
+#ifdef PNG_WARNINGS_SUPPORTED
 /* Non-fatal error in libpng.  Can continue, but may have a problem. */
-extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
-   png_const_charp warning_message));
+PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr,
+    png_const_charp warning_message));
+
+/* Non-fatal error in libpng, chunk name is prepended to message. */
+PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr,
+    png_const_charp warning_message));
+#else
+#  define png_warning(s1,s2) ((void)(s1))
+#  define png_chunk_warning(s1,s2) ((void)(s1))
+#endif
+
+#ifdef PNG_BENIGN_ERRORS_SUPPORTED
+/* Benign error in libpng.  Can continue, but may have a problem.
+ * User can choose whether to handle as a fatal error or as a warning. */
+PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr,
+    png_const_charp warning_message));
 
 #ifdef PNG_READ_SUPPORTED
-/* 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));
-#endif /* PNG_READ_SUPPORTED */
-#endif /* PNG_NO_WARNINGS */
+/* Same, chunk name is prepended to message (only during read) */
+PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr,
+    png_const_charp warning_message));
+#endif
+
+PNG_EXPORT(109, void, png_set_benign_errors,
+    (png_structrp png_ptr, int allowed));
+#else
+#  ifdef PNG_ALLOW_BENIGN_ERRORS
+#    define png_benign_error png_warning
+#    define png_chunk_benign_error png_chunk_warning
+#  else
+#    define png_benign_error png_error
+#    define png_chunk_benign_error png_chunk_error
+#  endif
+#endif
 
 /* The png_set_<chunk> functions are for storing values in the png_info_struct.
  * Similarly, the png_get_<chunk> calls are used to read values from the
  * png_info_struct, 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));
+PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, png_uint_32 flag));
 
 /* Returns number of bytes needed to hold a transformed row. */
-extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
-png_infop info_ptr));
+PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 #ifdef PNG_INFO_IMAGE_SUPPORTED
 /* Returns row_pointers, which is an array of pointers to scanlines that was
  * returned from png_read_png().
  */
-extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
-png_infop info_ptr));
+PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
+
 /* Set row_pointers, which is an array of pointers to scanlines for use
  * by png_write_png().
  */
-extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_bytepp row_pointers));
+PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_bytepp row_pointers));
 #endif
 
 /* Returns number of color channels in image. */
-extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
-png_infop info_ptr));
+PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 #ifdef PNG_EASY_ACCESS_SUPPORTED
 /* Returns image width in pixels. */
-extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 /* Returns image height in pixels. */
-extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 /* Returns image bit_depth. */
-extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 /* Returns image color_type. */
-extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 /* Returns image filter_type. */
-extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 /* Returns image interlace_type. */
-extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 /* Returns image compression_type. */
-extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
 
 /* Returns image resolution in pixels per meter, from pHYs chunk data. */
-extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
+PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
 
 /* Returns pixel aspect ratio, computed from pHYs chunk data.  */
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
-png_ptr, png_infop info_ptr));
-#endif
+PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr))
+PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr))
 
 /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
-extern PNG_EXPORT(png_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 */
-
+PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+
+#endif /* EASY_ACCESS */
+
+#ifdef PNG_READ_SUPPORTED
 /* Returns pointer to signature string read from PNG header */
-extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
-png_infop info_ptr));
+PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
+#endif
 
 #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));
+PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_color_16p *background));
 #endif
 
 #ifdef PNG_bKGD_SUPPORTED
-extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_color_16p background));
+PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_color_16p background));
 #endif
 
 #ifdef PNG_cHRM_SUPPORTED
-#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
+PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x,
+    double *red_y, double *green_x, double *green_y, double *blue_x,
+    double *blue_y))
+PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z,
+    double *green_X, double *green_Y, double *green_Z, double *blue_X,
+    double *blue_Y, double *blue_Z))
+PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr,
+    png_fixed_point *int_white_x, png_fixed_point *int_white_y,
+    png_fixed_point *int_red_x, png_fixed_point *int_red_y,
+    png_fixed_point *int_green_x, png_fixed_point *int_green_y,
+    png_fixed_point *int_blue_x, png_fixed_point *int_blue_y))
+PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr,
+    png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
+    png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
+    png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
+    png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
+    png_fixed_point *int_blue_Z))
 #endif
 
 #ifdef PNG_cHRM_SUPPORTED
-#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
+PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr,
+    png_inforp info_ptr,
+    double white_x, double white_y, double red_x, double red_y, double green_x,
+    double green_y, double blue_x, double blue_y))
+PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr,
+    png_inforp info_ptr, double red_X, double red_Y, double red_Z,
+    double green_X, double green_Y, double green_Z, double blue_X,
+    double blue_Y, double blue_Z))
+PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_fixed_point int_white_x,
+    png_fixed_point int_white_y, png_fixed_point int_red_x,
+    png_fixed_point int_red_y, png_fixed_point int_green_x,
+    png_fixed_point int_green_y, png_fixed_point int_blue_x,
+    png_fixed_point int_blue_y))
+PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,
+    png_fixed_point int_red_Z, png_fixed_point int_green_X,
+    png_fixed_point int_green_Y, png_fixed_point int_green_Z,
+    png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
+    png_fixed_point int_blue_Z))
 #endif
 
 #ifdef PNG_gAMA_SUPPORTED
-#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));
+PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, double *file_gamma))
+PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr,
+    png_fixed_point *int_file_gamma))
 #endif
 
 #ifdef PNG_gAMA_SUPPORTED
-#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));
+PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr,
+    png_inforp info_ptr, double file_gamma))
+PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_fixed_point int_file_gamma))
 #endif
 
 #ifdef PNG_hIST_SUPPORTED
-extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_uint_16p *hist));
+PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_uint_16p *hist));
 #endif
 
 #ifdef PNG_hIST_SUPPORTED
-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));
+PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_uint_16p hist));
+#endif
+
+PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height,
+    int *bit_depth, int *color_type, int *interlace_method,
+    int *compression_method, int *filter_method));
+
+PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
+    int color_type, int interlace_method, int compression_method,
+    int filter_method));
 
 #ifdef PNG_oFFs_SUPPORTED
-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,
+PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr,
+   png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
    int *unit_type));
 #endif
 
 #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));
+PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y,
+    int unit_type));
 #endif
 
 #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));
+PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_charp *purpose, png_int_32 *X0,
+    png_int_32 *X1, int *type, int *nparams, png_charp *units,
+    png_charpp *params));
 #endif
 
 #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));
+PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1,
+    int type, int nparams, png_const_charp units, png_charpp params));
 #endif
 
 #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));
+PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
+    int *unit_type));
 #endif
 
 #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));
+PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
+#endif
+
+PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr,
+   png_inforp info_ptr, png_colorp *palette, int *num_palette));
+
+PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr,
+    png_inforp info_ptr, png_const_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));
+PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr,
+    png_inforp 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));
+PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_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));
+PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, int *file_srgb_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));
+PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr,
+    png_inforp info_ptr, int srgb_intent));
+PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr,
+    png_inforp info_ptr, int srgb_intent));
 #endif
 
 #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 */
+PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_charpp name, int *compression_type,
+    png_bytepp profile, png_uint_32 *proflen));
 #endif
 
 #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 */
+PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_charp name, int compression_type,
+    png_const_bytep profile, png_uint_32 proflen));
 #endif
 
 #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));
+PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr,
+    png_inforp 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));
+PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_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.
+PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr,
+    png_inforp 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));
+PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_textp text_ptr, int num_text));
 #endif
 
 #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));
+PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr,
+    png_inforp 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));
+PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_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, int *num_trans,
-   png_color_16p *trans_values));
+PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans,
+    png_color_16p *trans_color));
 #endif
 
 #ifdef PNG_tRNS_SUPPORTED
-extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_bytep trans, int num_trans,
-   png_color_16p trans_values));
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
+PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr,
+    png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans,
+    png_const_color_16p trans_color));
 #endif
 
 #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));
+PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, int *unit, double *width, double *height))
+#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \
+   defined(PNG_FLOATING_POINT_SUPPORTED)
+/* NOTE: this API is currently implemented using floating point arithmetic,
+ * consequently it can only be used on systems with floating point support.
+ * In any case the range of values supported by png_fixed_point is small and it
+ * is highly recommended that png_get_sCAL_s be used instead.
+ */
+PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
+    png_fixed_point *width, png_fixed_point *height))
+#endif
+PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
+    png_charpp swidth, png_charpp sheight));
+
+PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr,
+    png_inforp info_ptr, int unit, double width, double height))
+PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr,
+   png_inforp info_ptr, int unit, png_fixed_point width,
+   png_fixed_point height))
+PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
+    png_inforp info_ptr, int unit,
+    png_const_charp swidth, png_const_charp sheight));
+#endif /* sCAL */
+
+#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
+/* Provide the default handling for all unknown chunks or, optionally, for
+ * specific unknown chunks.
+ *
+ * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was
+ * ignored and the default was used, the per-chunk setting only had an effect on
+ * write.  If you wish to have chunk-specific handling on read in code that must
+ * work on earlier versions you must use a user chunk callback to specify the
+ * desired handling (keep or discard.)
+ *
+ * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below.  The
+ * parameter is interpreted as follows:
+ *
+ * READ:
+ *    PNG_HANDLE_CHUNK_AS_DEFAULT:
+ *       Known chunks: do normal libpng processing, do not keep the chunk (but
+ *          see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
+ *       Unknown chunks: for a specific chunk use the global default, when used
+ *          as the default discard the chunk data.
+ *    PNG_HANDLE_CHUNK_NEVER:
+ *       Discard the chunk data.
+ *    PNG_HANDLE_CHUNK_IF_SAFE:
+ *       Keep the chunk data if the chunk is not critical else raise a chunk
+ *       error.
+ *    PNG_HANDLE_CHUNK_ALWAYS:
+ *       Keep the chunk data.
+ *
+ * If the chunk data is saved it can be retrieved using png_get_unknown_chunks,
+ * below.  Notice that specifying "AS_DEFAULT" as a global default is equivalent
+ * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks
+ * it simply resets the behavior to the libpng default.
+ *
+ * INTERACTION WTIH USER CHUNK CALLBACKS:
+ * The per-chunk handling is always used when there is a png_user_chunk_ptr
+ * callback and the callback returns 0; the chunk is then always stored *unless*
+ * it is critical and the per-chunk setting is other than ALWAYS.  Notice that
+ * the global default is *not* used in this case.  (In effect the per-chunk
+ * value is incremented to at least IF_SAFE.)
+ *
+ * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and
+ * per-chunk defaults will be honored.  If you want to preserve the current
+ * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE
+ * as the default - if you don't do this libpng 1.6 will issue a warning.
+ *
+ * If you want unhandled unknown chunks to be discarded in libpng 1.6 and
+ * earlier simply return '1' (handled).
+ *
+ * PNG_HANDLE_AS_UNKNOWN_SUPPORTED:
+ *    If this is *not* set known chunks will always be handled by libpng and
+ *    will never be stored in the unknown chunk list.  Known chunks listed to
+ *    png_set_keep_unknown_chunks will have no effect.  If it is set then known
+ *    chunks listed with a keep other than AS_DEFAULT will *never* be processed
+ *    by libpng, in addition critical chunks must either be processed by the
+ *    callback or saved.
+ *
+ *    The IHDR and IEND chunks must not be listed.  Because this turns off the
+ *    default handling for chunks that would otherwise be recognized the
+ *    behavior of libpng transformations may well become incorrect!
+ *
+ * WRITE:
+ *    When writing chunks the options only apply to the chunks specified by
+ *    png_set_unknown_chunks (below), libpng will *always* write known chunks
+ *    required by png_set_ calls and will always write the core critical chunks
+ *    (as required for PLTE).
+ *
+ *    Each chunk in the png_set_unknown_chunks list is looked up in the
+ *    png_set_keep_unknown_chunks list to find the keep setting, this is then
+ *    interpreted as follows:
+ *
+ *    PNG_HANDLE_CHUNK_AS_DEFAULT:
+ *       Write safe-to-copy chunks and write other chunks if the global
+ *       default is set to _ALWAYS, otherwise don't write this chunk.
+ *    PNG_HANDLE_CHUNK_NEVER:
+ *       Do not write the chunk.
+ *    PNG_HANDLE_CHUNK_IF_SAFE:
+ *       Write the chunk if it is safe-to-copy, otherwise do not write it.
+ *    PNG_HANDLE_CHUNK_ALWAYS:
+ *       Write the chunk.
+ *
+ * Note that the default behavior is effectively the opposite of the read case -
+ * in read unknown chunks are not stored by default, in write they are written
+ * by default.  Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different
+ * - on write the safe-to-copy bit is checked, on read the critical bit is
+ * checked and on read if the chunk is critical an error will be raised.
+ *
+ * num_chunks:
+ * ===========
+ *    If num_chunks is positive, then the "keep" parameter specifies the manner
+ *    for handling only those chunks appearing in the chunk_list array,
+ *    otherwise the chunk list array is ignored.
+ *
+ *    If num_chunks is 0 the "keep" parameter specifies the default behavior for
+ *    unknown chunks, as described above.
+ *
+ *    If num_chunks is negative, then the "keep" parameter specifies the manner
+ *    for handling all unknown chunks plus all chunks recognized by libpng
+ *    except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to
+ *    be processed by libpng.
+ */
+PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr,
+    int keep, png_const_bytep chunk_list, int num_chunks));
+
+/* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned;
+ * the result is therefore true (non-zero) if special handling is required,
+ * false for the default handling.
+ */
+PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr,
+    png_const_bytep chunk_name));
+#endif
+
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr,
+    png_inforp info_ptr, png_const_unknown_chunkp unknowns,
+    int num_unknowns));
+   /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added
+    * unknowns to the location currently stored in the png_struct.  This is
+    * invariably the wrong value on write.  To fix this call the following API
+    * for each chunk in the list with the correct location.  If you know your
+    * code won't be compiled on earlier versions you can rely on
+    * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing
+    * the correct thing.
+    */
+
+PNG_EXPORT(175, void, png_set_unknown_chunk_location,
+    (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location));
+
+PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr,
+    png_inforp 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));
+PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr,
+    png_inforp info_ptr, int mask));
 
 #ifdef PNG_INFO_IMAGE_SUPPORTED
 /* The "params" pointer is currently not used and is for future expansion. */
-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
-
-/* Define PNG_DEBUG at compile time for debugging information.  Higher
- * numbers for PNG_DEBUG mean more debugging information.  This has
- * only been added since version 0.95 so it is not implemented throughout
- * libpng yet, but more support will be added as needed.
- */
-#ifdef PNG_DEBUG
-#if (PNG_DEBUG > 0)
-#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
-#include <crtdbg.h>
-#if (PNG_DEBUG > 1)
-#ifndef _DEBUG
-#  define _DEBUG
-#endif
-#ifndef png_debug
-#define png_debug(l,m)  _RPT0(_CRT_WARN,m PNG_STRING_NEWLINE)
-#endif
-#ifndef png_debug1
-#define png_debug1(l,m,p1)  _RPT1(_CRT_WARN,m PNG_STRING_NEWLINE,p1)
-#endif
-#ifndef png_debug2
-#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m PNG_STRING_NEWLINE,p1,p2)
-#endif
-#endif
-#else /* PNG_DEBUG_FILE || !_MSC_VER */
-#ifndef PNG_DEBUG_FILE
-#define PNG_DEBUG_FILE stderr
-#endif /* PNG_DEBUG_FILE */
-
-#if (PNG_DEBUG > 1)
-/* Note: ["%s"m PNG_STRING_NEWLINE] probably does not work on non-ISO
- * compilers.
- */
-#  ifdef __STDC__
-#    ifndef png_debug
-#      define png_debug(l,m) \
-       { \
-       int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s" m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
-       }
-#    endif
-#    ifndef png_debug1
-#      define png_debug1(l,m,p1) \
-       { \
-       int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s" m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
-       }
-#    endif
-#    ifndef png_debug2
-#      define png_debug2(l,m,p1,p2) \
-       { \
-       int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s" m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
-       }
-#    endif
-#  else /* __STDC __ */
-#    ifndef png_debug
-#      define png_debug(l,m) \
-       { \
-       int num_tabs=l; \
-       char format[256]; \
-       snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
-         m,PNG_STRING_NEWLINE); \
-       fprintf(PNG_DEBUG_FILE,format); \
-       }
-#    endif
-#    ifndef png_debug1
-#      define png_debug1(l,m,p1) \
-       { \
-       int num_tabs=l; \
-       char format[256]; \
-       snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
-         m,PNG_STRING_NEWLINE); \
-       fprintf(PNG_DEBUG_FILE,format,p1); \
-       }
-#    endif
-#    ifndef png_debug2
-#      define png_debug2(l,m,p1,p2) \
-       { \
-       int num_tabs=l; \
-       char format[256]; \
-       snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
-         m,PNG_STRING_NEWLINE); \
-       fprintf(PNG_DEBUG_FILE,format,p1,p2); \
-       }
-#    endif
-#  endif /* __STDC __ */
-#endif /* (PNG_DEBUG > 1) */
-
-#endif /* _MSC_VER */
-#endif /* (PNG_DEBUG > 0) */
-#endif /* PNG_DEBUG */
-#ifndef png_debug
-#define png_debug(l, m)
-#endif
-#ifndef png_debug1
-#define png_debug1(l, m, p1)
-#endif
-#ifndef png_debug2
-#define png_debug2(l, m, p1, p2)
-#endif
-
-extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
-extern PNG_EXPORT(png_charp,png_get_header_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_SEQUENTIAL_READ_SUPPORTED
+PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr,
+    int transforms, png_voidp params));
+#endif
+#ifdef PNG_WRITE_SUPPORTED
+PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr,
+    int transforms, png_voidp params));
+#endif
+#endif
+
+PNG_EXPORT(180, png_const_charp, png_get_copyright,
+    (png_const_structrp png_ptr));
+PNG_EXPORT(181, png_const_charp, png_get_header_ver,
+    (png_const_structrp png_ptr));
+PNG_EXPORT(182, png_const_charp, png_get_header_version,
+    (png_const_structrp png_ptr));
+PNG_EXPORT(183, png_const_charp, png_get_libpng_ver,
+    (png_const_structrp png_ptr));
 
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
-   png_ptr, png_uint_32 mng_features_permitted));
+PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr,
+    png_uint_32 mng_features_permitted));
 #endif
 
 /* For use in png_set_keep_unknown, added to version 1.2.6 */
 #define PNG_HANDLE_CHUNK_AS_DEFAULT   0
 #define PNG_HANDLE_CHUNK_NEVER        1
 #define PNG_HANDLE_CHUNK_IF_SAFE      2
 #define PNG_HANDLE_CHUNK_ALWAYS       3
-
-/* Added to version 1.2.0 */
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-#ifdef PNG_MMX_CODE_SUPPORTED
-#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED  0x01  /* not user-settable */
-#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU    0x02  /* not user-settable */
-#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  0x04
-#define PNG_ASM_FLAG_MMX_READ_INTERLACE    0x08
-#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB   0x10
-#define PNG_ASM_FLAG_MMX_READ_FILTER_UP    0x20
-#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG   0x40
-#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
-#define PNG_ASM_FLAGS_INITIALIZED          0x80000000  /* not user-settable */
-
-#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
-                           | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
-                           | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-                           | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-                           | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-                           | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
-#define PNG_MMX_WRITE_FLAGS ( 0 )
-
-#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
-                      | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU   \
-                      | PNG_MMX_READ_FLAGS                \
-                      | PNG_MMX_WRITE_FLAGS )
-
-#define PNG_SELECT_READ   1
-#define PNG_SELECT_WRITE  2
-#endif /* PNG_MMX_CODE_SUPPORTED */
-
-#ifndef PNG_1_0_X
-/* pngget.c */
-extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
-   PNGARG((int flag_select, int *compilerID));
-
-/* pngget.c */
-extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
-   PNGARG((int flag_select));
-
-/* pngget.c */
-extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
-   PNGARG((png_structp png_ptr));
-
-/* pngget.c */
-extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
-   PNGARG((png_structp png_ptr));
-
-/* pngget.c */
-extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
-   PNGARG((png_structp png_ptr));
-
-/* pngset.c */
-extern PNG_EXPORT(void,png_set_asm_flags)
-   PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
-
-/* pngset.c */
-extern PNG_EXPORT(void,png_set_mmx_thresholds)
-   PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
-   png_uint_32 mmx_rowbytes_threshold));
-
-#endif /* PNG_1_0_X */
-
-#ifndef PNG_1_0_X
-/* png.c, pnggccrd.c, or pngvcrd.c */
-extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
-#endif /* PNG_1_0_X */
-#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+#define PNG_HANDLE_CHUNK_LAST         4
 
 /* Strip the prepended error numbers ("#nnn ") from error and warning
  * messages before passing them to the error or warning handler.
  */
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
-extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
-   png_ptr, png_uint_32 strip_mode));
+PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr,
+    png_uint_32 strip_mode));
 #endif
 
-/* Added at libpng-1.2.6 */
+/* 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));
+PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr,
+    png_uint_32 user_width_max, png_uint_32 user_height_max));
+PNG_EXPORT(187, png_uint_32, png_get_user_width_max,
+    (png_const_structrp png_ptr));
+PNG_EXPORT(188, png_uint_32, png_get_user_height_max,
+    (png_const_structrp png_ptr));
+/* Added in libpng-1.4.0 */
+PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr,
+    png_uint_32 user_chunk_cache_max));
+PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max,
+    (png_const_structrp png_ptr));
+/* Added in libpng-1.4.1 */
+PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr,
+    png_alloc_size_t user_chunk_cache_max));
+PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max,
+    (png_const_structrp png_ptr));
 #endif
-/* Maintainer: Put new public prototypes here ^, in libpng.3, and in
- * project defs
+
+#if defined(PNG_INCH_CONVERSIONS_SUPPORTED)
+PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+
+PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+
+PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr));
+
+PNG_FP_EXPORT(196, float, png_get_x_offset_inches,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr))
+#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
+PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr))
+#endif
+
+PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr))
+#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
+PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
+    (png_const_structrp png_ptr, png_const_inforp info_ptr))
+#endif
+
+#  ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
+    int *unit_type));
+#  endif /* pHYs */
+#endif  /* INCH_CONVERSIONS */
+
+/* Added in libpng-1.4.0 */
+#ifdef PNG_IO_STATE_SUPPORTED
+PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr));
+
+/* Removed from libpng 1.6; use png_get_io_chunk_type. */
+PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr),
+    PNG_DEPRECATED)
+
+PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
+    (png_const_structrp png_ptr));
+
+/* The flags returned by png_get_io_state() are the following: */
+#  define PNG_IO_NONE        0x0000   /* no I/O at this moment */
+#  define PNG_IO_READING     0x0001   /* currently reading */
+#  define PNG_IO_WRITING     0x0002   /* currently writing */
+#  define PNG_IO_SIGNATURE   0x0010   /* currently at the file signature */
+#  define PNG_IO_CHUNK_HDR   0x0020   /* currently at the chunk header */
+#  define PNG_IO_CHUNK_DATA  0x0040   /* currently at the chunk data */
+#  define PNG_IO_CHUNK_CRC   0x0080   /* currently at the chunk crc */
+#  define PNG_IO_MASK_OP     0x000f   /* current operation: reading/writing */
+#  define PNG_IO_MASK_LOC    0x00f0   /* current location: sig/hdr/data/crc */
+#endif /* IO_STATE */
+
+/* Interlace support.  The following macros are always defined so that if
+ * libpng interlace handling is turned off the macros may be used to handle
+ * interlaced images within the application.
  */
+#define PNG_INTERLACE_ADAM7_PASSES 7
+
+/* Two macros to return the first row and first column of the original,
+ * full, image which appears in a given pass.  'pass' is in the range 0
+ * to 6 and the result is in the range 0 to 7.
+ */
+#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7)
+#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7)
+
+/* A macro to return the offset between pixels in the output row for a pair of
+ * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that
+ * follows.  Note that ROW_OFFSET is the offset from one row to the next whereas
+ * COL_OFFSET is from one column to the next, within a row.
+ */
+#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8)
+#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1))
+
+/* Two macros to help evaluate the number of rows or columns in each
+ * pass.  This is expressed as a shift - effectively log2 of the number or
+ * rows or columns in each 8x8 tile of the original image.
+ */
+#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
+#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
+
+/* Hence two macros to determine the number of rows or columns in a given
+ * pass of an image given its height or width.  In fact these macros may
+ * return non-zero even though the sub-image is empty, because the other
+ * dimension may be empty for a small image.
+ */
+#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
+   -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
+#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
+   -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
+
+/* For the reader row callbacks (both progressive and sequential) it is
+ * necessary to find the row in the output image given a row in an interlaced
+ * image, so two more macros:
+ */
+#define PNG_ROW_FROM_PASS_ROW(y_in, pass) \
+   (((y_in)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
+#define PNG_COL_FROM_PASS_COL(x_in, pass) \
+   (((x_in)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
+
+/* Two macros which return a boolean (0 or 1) saying whether the given row
+ * or column is in a particular pass.  These use a common utility macro that
+ * returns a mask for a given pass - the offset 'off' selects the row or
+ * column version.  The mask has the appropriate bit set for each column in
+ * the tile.
+ */
+#define PNG_PASS_MASK(pass,off) ( \
+   ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \
+   ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0))
+
+#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
+   ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
+#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
+   ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
 
 #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); }
+ /* 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)) + 128);                \
+       (composite) = (png_byte)(((temp + (temp >> 8)) >> 8) & 0xff); }
+
+#  define png_composite_16(composite, fg, alpha, bg)       \
+     { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg)  \
+           * (png_uint_32)(alpha)                          \
+           + (png_uint_32)(bg)*(65535                      \
+           - (png_uint_32)(alpha)) + 32768);               \
+       (composite) = (png_uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); }
+
+#else  /* Standard method using integer division */
+
+#  define png_composite(composite, fg, alpha, bg)                        \
+     (composite) =                                                       \
+         (png_byte)(0xff & (((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
+         (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
+         127) / 255))
 
 #  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 */
-
-/* Inline macros to do direct reads of bytes from the input buffer.  These
- * require that you are using an architecture that uses PNG byte ordering
- * (MSB first) and supports unaligned data storage.  I think that PowerPC
- * in big-endian mode and 680x0 are the only ones that will support this.
- * The x86 line of processors definitely do not.  The png_get_int_32()
- * routine also assumes we are using two's complement format for negative
- * values, which is almost certainly true.
- */
-#ifdef PNG_READ_BIG_ENDIAN_SUPPORTED
-#  define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
-#  define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
-#  define png_get_int_32(buf)  ( *((png_int_32p)  (buf)))
-#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));
-extern PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf));
-#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
-extern PNG_EXPORT(png_uint_32,png_get_uint_31)
-  PNGARG((png_structp png_ptr, png_bytep buf));
+     (composite) =                                                           \
+         (png_uint_16)(0xffff & (((png_uint_32)(fg) * (png_uint_32)(alpha) + \
+         (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) +     \
+         32767) / 65535))
+#endif /* READ_COMPOSITE_NODIV */
+
+#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));
+PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf));
+PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf));
+#endif
+
+PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr,
+    png_const_bytep buf));
 /* No png_get_int_16 -- may be added if there's a real need for it. */
 
-/* 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 32-bit number into a buffer in PNG byte order (big-endian). */
+#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i));
+#endif
+#ifdef PNG_SAVE_INT_32_SUPPORTED
+PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i));
+#endif
 
 /* Place a 16-bit number into a buffer in PNG byte order.
  * The parameter is declared unsigned int, not png_uint_16,
  * just to avoid potential problems on pre-ANSI C compilers.
  */
-extern PNG_EXPORT(void,png_save_uint_16)
-   PNGARG((png_bytep buf, unsigned int i));
+#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
 /* No png_save_int_16 -- may be added if there's a real need for it. */
-
-/* ************************************************************************* */
-
-/* These next functions are used internally in the code.  They generally
- * shouldn't be used unless you are writing code to add or replace some
- * functionality in libpng.  More information about most functions can
- * be found in the files where the functions are located.
- */
-
-
-/* Various modes of operation, that are visible to applications because
- * they are used for unknown chunk location.
- */
-#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
-
-#ifdef PNG_INTERNAL
-
-/* More modes of operation.  Note that after an init, mode is set to
- * zero automatically when the structure is created.
- */
-#define PNG_HAVE_gAMA               0x20
-#define PNG_HAVE_cHRM               0x40
-#define PNG_HAVE_sRGB               0x80
-#define PNG_HAVE_CHUNK_HEADER      0x100
-#define PNG_WROTE_tIME             0x200
-#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
-#define PNG_BACKGROUND_IS_GRAY     0x800
-#define PNG_HAVE_PNG_SIGNATURE    0x1000
-#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
-
-/* Flags for the transformations the PNG library does on the image data */
-#define PNG_BGR                0x0001
-#define PNG_INTERLACE          0x0002
-#define PNG_PACK               0x0004
-#define PNG_SHIFT              0x0008
-#define PNG_SWAP_BYTES         0x0010
-#define PNG_INVERT_MONO        0x0020
-#define PNG_DITHER             0x0040
-#define PNG_BACKGROUND         0x0080
-#define PNG_BACKGROUND_EXPAND  0x0100
-                          /*   0x0200 unused */
-#define PNG_16_TO_8            0x0400
-#define PNG_RGBA               0x0800
-#define PNG_EXPAND             0x1000
-#define PNG_GAMMA              0x2000
-#define PNG_GRAY_TO_RGB        0x4000
-#define PNG_FILLER             0x8000L
-#define PNG_PACKSWAP          0x10000L
-#define PNG_SWAP_ALPHA        0x20000L
-#define PNG_STRIP_ALPHA       0x40000L
-#define PNG_INVERT_ALPHA      0x80000L
-#define PNG_USER_TRANSFORM   0x100000L
-#define PNG_RGB_TO_GRAY_ERR  0x200000L
-#define PNG_RGB_TO_GRAY_WARN 0x400000L
-#define PNG_RGB_TO_GRAY      0x600000L  /* two bits, RGB_TO_GRAY_ERR|WARN */
-                       /*    0x800000L     Unused */
-#define PNG_ADD_ALPHA       0x1000000L  /* Added to libpng-1.2.7 */
-#define PNG_EXPAND_tRNS     0x2000000L  /* Added to libpng-1.2.9 */
-#define PNG_PREMULTIPLY_ALPHA 0x4000000L  /* Added to libpng-1.2.41 */
-                                          /* by volker */
-                       /*   0x8000000L  unused */
-                       /*  0x10000000L  unused */
-                       /*  0x20000000L  unused */
-                       /*  0x40000000L  unused */
-
-/* Flags for png_create_struct */
-#define PNG_STRUCT_PNG   0x0001
-#define PNG_STRUCT_INFO  0x0002
-
-/* Scaling factor for filter heuristic weighting calculations */
-#define PNG_WEIGHT_SHIFT 8
-#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
-#define PNG_COST_SHIFT 3
-#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
-
-/* Flags for the png_ptr->flags rather than declaring a byte for each one */
-#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY     0x0001
-#define PNG_FLAG_ZLIB_CUSTOM_LEVEL        0x0002
-#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL    0x0004
-#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS  0x0008
-#define PNG_FLAG_ZLIB_CUSTOM_METHOD       0x0010
-#define PNG_FLAG_ZLIB_FINISHED            0x0020
-#define PNG_FLAG_ROW_INIT                 0x0040
-#define PNG_FLAG_FILLER_AFTER             0x0080
-#define PNG_FLAG_CRC_ANCILLARY_USE        0x0100
-#define PNG_FLAG_CRC_ANCILLARY_NOWARN     0x0200
-#define PNG_FLAG_CRC_CRITICAL_USE         0x0400
-#define PNG_FLAG_CRC_CRITICAL_IGNORE      0x0800
-#define PNG_FLAG_FREE_PLTE                0x1000
-#define PNG_FLAG_FREE_TRNS                0x2000
-#define PNG_FLAG_FREE_HIST                0x4000
-#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS      0x8000L
-#define PNG_FLAG_KEEP_UNSAFE_CHUNKS       0x10000L
-#define PNG_FLAG_LIBRARY_MISMATCH         0x20000L
-#define PNG_FLAG_STRIP_ERROR_NUMBERS      0x40000L
-#define PNG_FLAG_STRIP_ERROR_TEXT         0x80000L
-#define PNG_FLAG_MALLOC_NULL_MEM_OK       0x100000L
-#define PNG_FLAG_ADD_ALPHA                0x200000L  /* Added to libpng-1.2.8 */
-#define PNG_FLAG_STRIP_ALPHA              0x400000L  /* Added to libpng-1.2.8 */
-                                  /*      0x800000L  unused */
-                                  /*     0x1000000L  unused */
-                                  /*     0x2000000L  unused */
-                                  /*     0x4000000L  unused */
-                                  /*     0x8000000L  unused */
-                                  /*    0x10000000L  unused */
-                                  /*    0x20000000L  unused */
-                                  /*    0x40000000L  unused */
-
-#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
-                                     PNG_FLAG_CRC_ANCILLARY_NOWARN)
-
-#define PNG_FLAG_CRC_CRITICAL_MASK  (PNG_FLAG_CRC_CRITICAL_USE | \
-                                     PNG_FLAG_CRC_CRITICAL_IGNORE)
-
-#define PNG_FLAG_CRC_MASK           (PNG_FLAG_CRC_ANCILLARY_MASK | \
-                                     PNG_FLAG_CRC_CRITICAL_MASK)
-
-/* Save typing and make code easier to understand */
-
-#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
-   abs((int)((c1).green) - (int)((c2).green)) + \
-   abs((int)((c1).blue) - (int)((c2).blue)))
-
-/* Added to libpng-1.2.6 JB */
-#define PNG_ROWBYTES(pixel_bits, width) \
-    ((pixel_bits) >= 8 ? \
-    ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
-    (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
-
-/* PNG_OUT_OF_RANGE returns true if value is outside the range
- * ideal-delta..ideal+delta.  Each argument is evaluated twice.
- * "ideal" and "delta" should be constants, normally simple
- * integers, "value" a variable. Added to libpng-1.2.6 JB
- */
-#define PNG_OUT_OF_RANGE(value, ideal, delta) \
-        ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
-
-/* Variables declared in png.c - only it needs to define PNG_NO_EXTERN */
-#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
-/* Place to hold the signature string for a PNG file. */
-#ifdef PNG_USE_GLOBAL_ARRAYS
-   PNG_EXPORT_VAR (PNG_CONST png_byte FARDATA) png_sig[8];
+#endif
+
+#ifdef PNG_USE_READ_MACROS
+/* Inline macros to do direct reads of bytes from the input buffer.
+ * The png_get_int_32() routine assumes we are using two's complement
+ * format for negative values, which is almost certainly true.
+ */
+#  define PNG_get_uint_32(buf) \
+     (((png_uint_32)(*(buf)) << 24) + \
+      ((png_uint_32)(*((buf) + 1)) << 16) + \
+      ((png_uint_32)(*((buf) + 2)) << 8) + \
+      ((png_uint_32)(*((buf) + 3))))
+
+   /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
+    * function) incorrectly returned a value of type png_uint_32.
+    */
+#  define PNG_get_uint_16(buf) \
+     ((png_uint_16) \
+      (((unsigned int)(*(buf)) << 8) + \
+       ((unsigned int)(*((buf) + 1)))))
+
+#  define PNG_get_int_32(buf) \
+     ((png_int_32)((*(buf) & 0x80) \
+      ? -((png_int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \
+      : (png_int_32)png_get_uint_32(buf)))
+
+   /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h,
+    * but defining a macro name prefixed with PNG_PREFIX.
+    */
+#  ifndef PNG_PREFIX
+#     define png_get_uint_32(buf) PNG_get_uint_32(buf)
+#     define png_get_uint_16(buf) PNG_get_uint_16(buf)
+#     define png_get_int_32(buf)  PNG_get_int_32(buf)
+#  endif
 #else
-#endif
-#endif /* PNG_NO_EXTERN */
-
-/* Constant strings for known chunk types.  If you need to add a chunk,
- * define the name here, and add an invocation of the macro in png.c and
- * wherever it's needed.
- */
-#define PNG_IHDR png_byte png_IHDR[5] = { 73,  72,  68,  82, '\0'}
-#define PNG_IDAT png_byte png_IDAT[5] = { 73,  68,  65,  84, '\0'}
-#define PNG_IEND png_byte png_IEND[5] = { 73,  69,  78,  68, '\0'}
-#define PNG_PLTE png_byte png_PLTE[5] = { 80,  76,  84,  69, '\0'}
-#define PNG_bKGD png_byte png_bKGD[5] = { 98,  75,  71,  68, '\0'}
-#define PNG_cHRM png_byte png_cHRM[5] = { 99,  72,  82,  77, '\0'}
-#define PNG_gAMA png_byte png_gAMA[5] = {103,  65,  77,  65, '\0'}
-#define PNG_hIST png_byte png_hIST[5] = {104,  73,  83,  84, '\0'}
-#define PNG_iCCP png_byte png_iCCP[5] = {105,  67,  67,  80, '\0'}
-#define PNG_iTXt png_byte png_iTXt[5] = {105,  84,  88, 116, '\0'}
-#define PNG_oFFs png_byte png_oFFs[5] = {111,  70,  70, 115, '\0'}
-#define PNG_pCAL png_byte png_pCAL[5] = {112,  67,  65,  76, '\0'}
-#define PNG_sCAL png_byte png_sCAL[5] = {115,  67,  65,  76, '\0'}
-#define PNG_pHYs png_byte png_pHYs[5] = {112,  72,  89, 115, '\0'}
-#define PNG_sBIT png_byte png_sBIT[5] = {115,  66,  73,  84, '\0'}
-#define PNG_sPLT png_byte png_sPLT[5] = {115,  80,  76,  84, '\0'}
-#define PNG_sRGB png_byte png_sRGB[5] = {115,  82,  71,  66, '\0'}
-#define PNG_tEXt png_byte png_tEXt[5] = {116,  69,  88, 116, '\0'}
-#define PNG_tIME png_byte png_tIME[5] = {116,  73,  77,  69, '\0'}
-#define PNG_tRNS png_byte png_tRNS[5] = {116,  82,  78,  83, '\0'}
-#define PNG_zTXt png_byte png_zTXt[5] = {122,  84,  88, 116, '\0'}
-
-#ifdef PNG_USE_GLOBAL_ARRAYS
-PNG_EXPORT_VAR (png_byte FARDATA) png_IHDR[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_IDAT[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_IEND[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_PLTE[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_bKGD[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_cHRM[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_gAMA[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_hIST[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_iCCP[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_iTXt[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_oFFs[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_pCAL[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_sCAL[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_pHYs[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_sBIT[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_sPLT[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_sRGB[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_tEXt[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_tIME[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_tRNS[5];
-PNG_EXPORT_VAR (png_byte FARDATA) png_zTXt[5];
-#endif /* PNG_USE_GLOBAL_ARRAYS */
-
-#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
-/* Initialize png_ptr struct for reading, and allocate any other memory.
- * (old interface - DEPRECATED - use png_create_read_struct instead).
- */
-extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr))
-    PNG_DEPRECATED;
-#undef png_read_init
-#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
-    PNG_LIBPNG_VER_STRING,  png_sizeof(png_struct));
-#endif
-
-extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
-    png_const_charp user_png_ver, png_size_t png_struct_size));
-#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
-extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
-    png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
-    png_info_size));
-#endif
-
-#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
-/* Initialize png_ptr struct for writing, and allocate any other memory.
- * (old interface - DEPRECATED - use png_create_write_struct instead).
- */
-extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr))
-    PNG_DEPRECATED;
-#undef png_write_init
-#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
-    PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
-#endif
-
-extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
-    png_const_charp user_png_ver, png_size_t png_struct_size));
-extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
-    png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
-    png_info_size));
-
-/* Allocate memory for an internal libpng struct */
-PNG_EXTERN png_voidp png_create_struct PNGARG((int type)) PNG_PRIVATE;
-
-/* Free memory from internal libpng struct */
-PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr)) PNG_PRIVATE;
-
-PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
-  malloc_fn, png_voidp mem_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
-   png_free_ptr free_fn, png_voidp mem_ptr)) PNG_PRIVATE;
-
-/* Free any memory that info_ptr points to and reset struct. */
-PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-
-#ifndef PNG_1_0_X
-/* Function to allocate memory for zlib. */
-PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items,
-   uInt size)) PNG_PRIVATE;
-
-/* Function to free memory for zlib */
-PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr)) PNG_PRIVATE;
-
-#ifdef PNG_SIZE_T
-/* Function to convert a sizeof an item to png_sizeof item */
-   PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size))
-      PNG_PRIVATE;
-#endif
-
-/* Next four functions are used internally as callbacks.  PNGAPI is required
- * but not PNG_EXPORT.  PNGAPI added at libpng version 1.2.3.
- */
-
-PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
-   png_bytep data, png_size_t length)) PNG_PRIVATE;
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
-   png_bytep buffer, png_size_t length)) PNG_PRIVATE;
-#endif
-
-PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
-   png_bytep data, png_size_t length)) PNG_PRIVATE;
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
+#  ifdef PNG_PREFIX
+      /* No macros; revert to the (redefined) function */
+#     define PNG_get_uint_32 (png_get_uint_32)
+#     define PNG_get_uint_16 (png_get_uint_16)
+#     define PNG_get_int_32  (png_get_int_32)
+#  endif
+#endif
+
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+PNG_EXPORT(242, void, png_set_check_for_invalid_index,
+    (png_structrp png_ptr, int allowed));
+#  ifdef PNG_GET_PALETTE_MAX_SUPPORTED
+PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+#  endif
+#endif /* CHECK_FOR_INVALID_INDEX */
+
+/*******************************************************************************
+ * Section 5: SIMPLIFIED API
+ *******************************************************************************
+ *
+ * Please read the documentation in libpng-manual.txt (TODO: write said
+ * documentation) if you don't understand what follows.
+ *
+ * The simplified API hides the details of both libpng and the PNG file format
+ * itself.  It allows PNG files to be read into a very limited number of
+ * in-memory bitmap formats or to be written from the same formats.  If these
+ * formats do not accomodate your needs then you can, and should, use the more
+ * sophisticated APIs above - these support a wide variety of in-memory formats
+ * and a wide variety of sophisticated transformations to those formats as well
+ * as a wide variety of APIs to manipulate ancillary information.
+ *
+ * To read a PNG file using the simplified API:
+ *
+ * 1) Declare a 'png_image' structure (see below) on the stack, set the
+ *    version field to PNG_IMAGE_VERSION and the 'opaque' pointer to NULL
+ *    (this is REQUIRED, your program may crash if you don't do it.)
+ * 2) Call the appropriate png_image_begin_read... function.
+ * 3) Set the png_image 'format' member to the required sample format.
+ * 4) Allocate a buffer for the image and, if required, the color-map.
+ * 5) Call png_image_finish_read to read the image and, if required, the
+ *    color-map into your buffers.
+ *
+ * There are no restrictions on the format of the PNG input itself; all valid
+ * color types, bit depths, and interlace methods are acceptable, and the
+ * input image is transformed as necessary to the requested in-memory format
+ * during the png_image_finish_read() step.  The only caveat is that if you
+ * request a color-mapped image from a PNG that is full-color or makes
+ * complex use of an alpha channel the transformation is extremely lossy and the
+ * result may look terrible.
+ *
+ * To write a PNG file using the simplified API:
+ *
+ * 1) Declare a 'png_image' structure on the stack and memset() it to all zero.
+ * 2) Initialize the members of the structure that describe the image, setting
+ *    the 'format' member to the format of the image samples.
+ * 3) Call the appropriate png_image_write... function with a pointer to the
+ *    image and, if necessary, the color-map to write the PNG data.
+ *
+ * png_image is a structure that describes the in-memory format of an image
+ * when it is being read or defines the in-memory format of an image that you
+ * need to write:
+ */
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) || \
+    defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
+
+#define PNG_IMAGE_VERSION 1
+
+typedef struct png_control *png_controlp;
+typedef struct
+{
+   png_controlp opaque;    /* Initialize to NULL, free with png_image_free */
+   png_uint_32  version;   /* Set to PNG_IMAGE_VERSION */
+   png_uint_32  width;     /* Image width in pixels (columns) */
+   png_uint_32  height;    /* Image height in pixels (rows) */
+   png_uint_32  format;    /* Image format as defined below */
+   png_uint_32  flags;     /* A bit mask containing informational flags */
+   png_uint_32  colormap_entries;
+                           /* Number of entries in the color-map */
+
+   /* In the event of an error or warning the following field will be set to a
+    * non-zero value and the 'message' field will contain a '\0' terminated
+    * string with the libpng error or warning message.  If both warnings and
+    * an error were encountered, only the error is recorded.  If there
+    * are multiple warnings, only the first one is recorded.
+    *
+    * The upper 30 bits of this value are reserved, the low two bits contain
+    * a value as follows:
+    */
+#  define PNG_IMAGE_WARNING 1
+#  define PNG_IMAGE_ERROR 2
+   /*
+    * The result is a two-bit code such that a value more than 1 indicates
+    * a failure in the API just called:
+    *
+    *    0 - no warning or error
+    *    1 - warning
+    *    2 - error
+    *    3 - error preceded by warning
+    */
+#  define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1)
+
+   png_uint_32  warning_or_error;
+
+   char         message[64];
+} png_image, *png_imagep;
+
+/* The samples of the image have one to four channels whose components have
+ * original values in the range 0 to 1.0:
+ *
+ * 1: A single gray or luminance channel (G).
+ * 2: A gray/luminance channel and an alpha channel (GA).
+ * 3: Three red, green, blue color channels (RGB).
+ * 4: Three color channels and an alpha channel (RGBA).
+ *
+ * The components are encoded in one of two ways:
+ *
+ * a) As a small integer, value 0..255, contained in a single byte.  For the
+ * alpha channel the original value is simply value/255.  For the color or
+ * luminance channels the value is encoded according to the sRGB specification
+ * and matches the 8-bit format expected by typical display devices.
+ *
+ * The color/gray channels are not scaled (pre-multiplied) by the alpha
+ * channel and are suitable for passing to color management software.
+ *
+ * b) As a value in the range 0..65535, contained in a 2-byte integer.  All
+ * channels can be converted to the original value by dividing by 65535; all
+ * channels are linear.  Color channels use the RGB encoding (RGB end-points) of
+ * the sRGB specification.  This encoding is identified by the
+ * PNG_FORMAT_FLAG_LINEAR flag below.
+ *
+ * When the simplified API needs to convert between sRGB and linear colorspaces,
+ * the actual sRGB transfer curve defined in the sRGB specification (see the
+ * article at http://en.wikipedia.org/wiki/SRGB) is used, not the gamma=1/2.2
+ * approximation used elsewhere in libpng.
+ *
+ * When an alpha channel is present it is expected to denote pixel coverage
+ * of the color or luminance channels and is returned as an associated alpha
+ * channel: the color/gray channels are scaled (pre-multiplied) by the alpha
+ * value.
+ *
+ * The samples are either contained directly in the image data, between 1 and 8
+ * bytes per pixel according to the encoding, or are held in a color-map indexed
+ * by bytes in the image data.  In the case of a color-map the color-map entries
+ * are individual samples, encoded as above, and the image data has one byte per
+ * pixel to select the relevant sample from the color-map.
+ */
+
+/* PNG_FORMAT_*
+ *
+ * #defines to be used in png_image::format.  Each #define identifies a
+ * particular layout of sample data and, if present, alpha values.  There are
+ * separate defines for each of the two component encodings.
+ *
+ * A format is built up using single bit flag values.  All combinations are
+ * valid.  Formats can be built up from the flag values or you can use one of
+ * the predefined values below.  When testing formats always use the FORMAT_FLAG
+ * macros to test for individual features - future versions of the library may
+ * add new flags.
+ *
+ * When reading or writing color-mapped images the format should be set to the
+ * format of the entries in the color-map then png_image_{read,write}_colormap
+ * called to read or write the color-map and set the format correctly for the
+ * image data.  Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly!
+ *
+ * NOTE: libpng can be built with particular features disabled. If you see
+ * compiler errors because the definition of one of the following flags has been
+ * compiled out it is because libpng does not have the required support.  It is
+ * possible, however, for the libpng configuration to enable the format on just
+ * read or just write; in that case you may see an error at run time.  You can
+ * guard against this by checking for the definition of the appropriate
+ * "_SUPPORTED" macro, one of:
+ *
+ *    PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED
+ */
+#define PNG_FORMAT_FLAG_ALPHA    0x01U /* format with an alpha channel */
+#define PNG_FORMAT_FLAG_COLOR    0x02U /* color format: otherwise grayscale */
+#define PNG_FORMAT_FLAG_LINEAR   0x04U /* 2-byte channels else 1-byte */
+#define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */
+
+#ifdef PNG_FORMAT_BGR_SUPPORTED
+#  define PNG_FORMAT_FLAG_BGR    0x10U /* BGR colors, else order is RGB */
+#endif
+
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
+#  define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */
+#endif
+
+/* Commonly used formats have predefined macros.
+ *
+ * First the single byte (sRGB) formats:
+ */
+#define PNG_FORMAT_GRAY 0
+#define PNG_FORMAT_GA   PNG_FORMAT_FLAG_ALPHA
+#define PNG_FORMAT_AG   (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST)
+#define PNG_FORMAT_RGB  PNG_FORMAT_FLAG_COLOR
+#define PNG_FORMAT_BGR  (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR)
+#define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA)
+#define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST)
+#define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA)
+#define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST)
+
+/* Then the linear 2-byte formats.  When naming these "Y" is used to
+ * indicate a luminance (gray) channel.
+ */
+#define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR
+#define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA)
+#define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR)
+#define PNG_FORMAT_LINEAR_RGB_ALPHA \
+   (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA)
+
+/* With color-mapped formats the image data is one byte for each pixel, the byte
+ * is an index into the color-map which is formatted as above.  To obtain a
+ * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP
+ * to one of the above definitions, or you can use one of the definitions below.
+ */
+#define PNG_FORMAT_RGB_COLORMAP  (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_BGR_COLORMAP  (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP)
+#define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP)
+
+/* PNG_IMAGE macros
+ *
+ * These are convenience macros to derive information from a png_image
+ * structure.  The PNG_IMAGE_SAMPLE_ macros return values appropriate to the
+ * actual image sample values - either the entries in the color-map or the
+ * pixels in the image.  The PNG_IMAGE_PIXEL_ macros return corresponding values
+ * for the pixels and will always return 1 for color-mapped formats.  The
+ * remaining macros return information about the rows in the image and the
+ * complete image.
+ *
+ * NOTE: All the macros that take a png_image::format parameter are compile time
+ * constants if the format parameter is, itself, a constant.  Therefore these
+ * macros can be used in array declarations and case labels where required.
+ * Similarly the macros are also pre-processor constants (sizeof is not used) so
+ * they can be used in #if tests.
+ *
+ * First the information about the samples.
+ */
+#define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\
+   (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1)
+   /* Return the total number of channels in a given format: 1..4 */
+
+#define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\
+   ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1)
+   /* Return the size in bytes of a single component of a pixel or color-map
+    * entry (as appropriate) in the image: 1 or 2.
+    */
+
+#define PNG_IMAGE_SAMPLE_SIZE(fmt)\
+   (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt))
+   /* This is the size of the sample data for one sample.  If the image is
+    * color-mapped it is the size of one color-map entry (and image pixels are
+    * one byte in size), otherwise it is the size of one image pixel.
+    */
+
+#define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\
+   (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256)
+   /* The maximum size of the color-map required by the format expressed in a
+    * count of components.  This can be used to compile-time allocate a
+    * color-map:
+    *
+    * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)];
+    *
+    * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)];
+    *
+    * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the
+    * information from one of the png_image_begin_read_ APIs and dynamically
+    * allocate the required memory.
+    */
+
+/* Corresponding information about the pixels */
+#define PNG_IMAGE_PIXEL_(test,fmt)\
+   (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt))
+
+#define PNG_IMAGE_PIXEL_CHANNELS(fmt)\
+   PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt)
+   /* The number of separate channels (components) in a pixel; 1 for a
+    * color-mapped image.
+    */
+
+#define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\
+   PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt)
+   /* The size, in bytes, of each component in a pixel; 1 for a color-mapped
+    * image.
+    */
+
+#define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt)
+   /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */
+
+/* Information about the whole row, or whole image */
+#define PNG_IMAGE_ROW_STRIDE(image)\
+   (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width)
+   /* Return the total number of components in a single row of the image; this
+    * is the minimum 'row stride', the minimum count of components between each
+    * row.  For a color-mapped image this is the minimum number of bytes in a
+    * row.
+    *
+    * WARNING: this macro overflows for some images with more than one component
+    * and very large image widths.  libpng will refuse to process an image where
+    * this macro would overflow.
+    */
+
+#define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\
+   (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride))
+   /* Return the size, in bytes, of an image buffer given a png_image and a row
+    * stride - the number of components to leave space for in each row.
+    *
+    * WARNING: this macro overflows a 32-bit integer for some large PNG images,
+    * libpng will refuse to process an image where such an overflow would occur.
+    */
+
+#define PNG_IMAGE_SIZE(image)\
+   PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image))
+   /* Return the size, in bytes, of the image in memory given just a png_image;
+    * the row stride is the minimum stride required for the image.
+    */
+
+#define PNG_IMAGE_COLORMAP_SIZE(image)\
+   (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries)
+   /* Return the size, in bytes, of the color-map of this image.  If the image
+    * format is not a color-map format this will return a size sufficient for
+    * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if
+    * you don't want to allocate a color-map in this case.
+    */
+
+/* PNG_IMAGE_FLAG_*
+ *
+ * Flags containing additional information about the image are held in the
+ * 'flags' field of png_image.
+ */
+#define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01
+   /* This indicates the the RGB values of the in-memory bitmap do not
+    * correspond to the red, green and blue end-points defined by sRGB.
+    */
+
+#define PNG_IMAGE_FLAG_FAST 0x02
+   /* On write emphasise speed over compression; the resultant PNG file will be
+    * larger but will be produced significantly faster, particular for large
+    * images.  Do not use this option for images which will be distributed, only
+    * used it when producing intermediate files that will be read back in
+    * repeatedly.  For a typical 24-bit image the option will double the read
+    * speed at the cost of increasing the image size by 25%, however for many
+    * more compressible images the PNG file can be 10 times larger with only a
+    * slight speed gain.
+    */
+
+#define PNG_IMAGE_FLAG_16BIT_sRGB 0x04
+   /* On read if the image is a 16-bit per component image and there is no gAMA
+    * or sRGB chunk assume that the components are sRGB encoded.  Notice that
+    * images output by the simplified API always have gamma information; setting
+    * this flag only affects the interpretation of 16-bit images from an
+    * external source.  It is recommended that the application expose this flag
+    * to the user; the user can normally easily recognize the difference between
+    * linear and sRGB encoding.  This flag has no effect on write - the data
+    * passed to the write APIs must have the correct encoding (as defined
+    * above.)
+    *
+    * If the flag is not set (the default) input 16-bit per component data is
+    * assumed to be linear.
+    *
+    * NOTE: the flag can only be set after the png_image_begin_read_ call,
+    * because that call initializes the 'flags' field.
+    */
+
+#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
+/* READ APIs
+ * ---------
+ *
+ * The png_image passed to the read APIs must have been initialized by setting
+ * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.)
+ */
 #ifdef PNG_STDIO_SUPPORTED
-PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr))
-   PNG_PRIVATE;
-#endif
-#endif
-#else /* PNG_1_0_X */
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
-   png_bytep buffer, png_size_t length)) PNG_PRIVATE;
-#endif
-#endif /* PNG_1_0_X */
-
-/* Reset the CRC variable */
-PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-/* Write the "data" buffer to whatever output you are using. */
-PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
-   png_size_t length)) PNG_PRIVATE;
-
-/* Read data from whatever input you are using into the "data" buffer */
-PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
-   png_size_t length)) PNG_PRIVATE;
-
-/* Read bytes into buf, and update png_ptr->crc */
-PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
-   png_size_t length)) PNG_PRIVATE;
-
-/* Decompress data in a chunk that uses compression */
-#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
-    defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
-PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,
-   int comp_type, png_size_t chunklength,
-   png_size_t prefix_length, png_size_t *data_length)) PNG_PRIVATE;
-#endif
-
-/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
-PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip)
-   PNG_PRIVATE);
-
-/* Read the CRC from the file and compare it to the libpng calculated CRC */
-PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-/* Calculate the CRC over a section of data.  Note that we are only
- * passing a maximum of 64K on systems that have this as a memory limit,
- * since this is the maximum buffer size we can specify.
- */
-PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
-   png_size_t length)) PNG_PRIVATE;
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-PNG_EXTERN void png_flush PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-#endif
-
-/* Simple function to write the signature */
-PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-/* Write various chunks */
-
-/* Write the IHDR chunk, and update the png_struct with the necessary
- * information.
- */
-PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
-   png_uint_32 height,
-   int bit_depth, int color_type, int compression_method, int filter_method,
-   int interlace_method)) PNG_PRIVATE;
-
-PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
-   png_uint_32 num_pal)) PNG_PRIVATE;
-
-PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
-   png_size_t length)) PNG_PRIVATE;
-
-PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-#ifdef PNG_WRITE_gAMA_SUPPORTED
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma))
-    PNG_PRIVATE;
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
-PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr,
-    png_fixed_point file_gamma)) PNG_PRIVATE;
-#endif
-#endif
-
-#ifdef PNG_WRITE_sBIT_SUPPORTED
-PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
-   int color_type)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_cHRM_SUPPORTED
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
-   double white_x, double white_y,
-   double red_x, double red_y, double green_x, double green_y,
-   double blue_x, double blue_y)) PNG_PRIVATE;
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
-PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
-   png_fixed_point int_white_x, png_fixed_point int_white_y,
-   png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
-   int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
-   png_fixed_point int_blue_y)) PNG_PRIVATE;
-#endif
-#endif
-
-#ifdef PNG_WRITE_sRGB_SUPPORTED
-PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
-   int intent)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_iCCP_SUPPORTED
-PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
-   png_charp name, int compression_type,
-   png_charp profile, int proflen)) PNG_PRIVATE;
-   /* Note to maintainer: profile should be png_bytep */
-#endif
-
-#ifdef PNG_WRITE_sPLT_SUPPORTED
-PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
-   png_sPLT_tp palette)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_tRNS_SUPPORTED
-PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
-   png_color_16p values, int number, int color_type)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_bKGD_SUPPORTED
-PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
-   png_color_16p values, int color_type)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_hIST_SUPPORTED
-PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
-   int num_hist)) PNG_PRIVATE;
-#endif
-
-#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
-    defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
-PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
-   png_charp key, png_charpp new_key)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_tEXt_SUPPORTED
-PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
-   png_charp text, png_size_t text_len)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_zTXt_SUPPORTED
-PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
-   png_charp text, png_size_t text_len, int compression)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_iTXt_SUPPORTED
-PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
-   int compression, png_charp key, png_charp lang, png_charp lang_key,
-   png_charp text)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED  /* Added at version 1.0.14 and 1.2.4 */
-PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_textp text_ptr, int num_text)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_oFFs_SUPPORTED
-PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
-   png_int_32 x_offset, png_int_32 y_offset, int unit_type)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_pCAL_SUPPORTED
-PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
-   png_int_32 X0, png_int_32 X1, int type, int nparams,
-   png_charp units, png_charpp params)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_pHYs_SUPPORTED
-PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
-   png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
-   int unit_type)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_tIME_SUPPORTED
-PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
-   png_timep mod_time)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_sCAL_SUPPORTED
-#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
-PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
-   int unit, double width, double height)) PNG_PRIVATE;
-#else
-#ifdef PNG_FIXED_POINT_SUPPORTED
-PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
-   int unit, png_charp width, png_charp height)) PNG_PRIVATE;
-#endif
-#endif
-#endif
-
-/* Called when finished processing a row of data */
-PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-/* Internal use only.   Called before first row of data */
-PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-#endif
-
-/* Combine a row of data, dealing with alpha, etc. if requested */
-PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
-   int mask)) PNG_PRIVATE;
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-/* Expand an interlaced row */
-/* OLD pre-1.0.9 interface:
-PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
-   png_bytep row, int pass, png_uint_32 transformations)) PNG_PRIVATE;
- */
-PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-#endif
-
-/* GRR TO DO (2.0 or whenever):  simplify other internal calling interfaces */
-
-#ifdef PNG_WRITE_INTERLACING_SUPPORTED
-/* Grab pixels out of a row for an interlaced pass */
-PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
-   png_bytep row, int pass)) PNG_PRIVATE;
-#endif
-
-/* Unfilter a row */
-PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
-   png_row_infop row_info, png_bytep row, png_bytep prev_row,
-   int filter)) PNG_PRIVATE;
-
-/* Choose the best filter to use and filter the row data */
-PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
-   png_row_infop row_info)) PNG_PRIVATE;
-
-/* Write out the filtered row. */
-PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
-   png_bytep filtered_row)) PNG_PRIVATE;
-/* Finish a row while reading, dealing with interlacing passes, etc. */
-PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
-
-/* Initialize the row buffers, etc. */
-PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-/* Optional call to update the users info structure */
-PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-
-/* These are the functions that do the transformations */
-#ifdef PNG_READ_FILLER_SUPPORTED
-PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
-   png_bytep row, png_uint_32 filler, png_uint_32 flags)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
-   png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
-   png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
-   png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
-   png_bytep row)) PNG_PRIVATE;
-#endif
-
-#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
-    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
-   png_bytep row, png_uint_32 flags)) PNG_PRIVATE;
-#endif
-
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info,
-    png_bytep row)) PNG_PRIVATE;
-#endif
-
-#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info,
-    png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
-   row_info, png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
-   png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_PACK_SUPPORTED
-PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info,
-    png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
-   png_color_8p sig_bits)) PNG_PRIVATE;
-#endif
-
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info,
-    png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_16_TO_8_SUPPORTED
-PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info,
-    png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_DITHER_SUPPORTED
-PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
-   png_bytep row, png_bytep palette_lookup,
-    png_bytep dither_lookup)) PNG_PRIVATE;
-
-#  ifdef PNG_CORRECT_PALETTE_SUPPORTED
-PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
-   png_colorp palette, int num_palette)) PNG_PRIVATE;
-#  endif
-#endif
-
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info,
-    png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_PACK_SUPPORTED
-PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
-   png_bytep row, png_uint_32 bit_depth)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_WRITE_SHIFT_SUPPORTED
-PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
-   png_color_8p bit_depth)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-#ifdef PNG_READ_GAMMA_SUPPORTED
-PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
-   png_color_16p trans_values, png_color_16p background,
-   png_color_16p background_1,
-   png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
-   png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
-   png_uint_16pp gamma_16_to_1, int gamma_shift)) PNG_PRIVATE;
-#else
-PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
-   png_color_16p trans_values, png_color_16p background)) PNG_PRIVATE;
-#endif
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
-   png_bytep gamma_table, png_uint_16pp gamma_16_table,
-   int gamma_shift)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
-   png_bytep row, png_colorp palette, png_bytep trans,
-   int num_trans)) PNG_PRIVATE;
-PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
-   png_bytep row, png_color_16p trans_value)) PNG_PRIVATE;
-#endif
-
-/* The following decodes the appropriate chunks, and does error correction,
- * then calls the appropriate callback for the chunk if it is valid.
- */
-
-/* Decode the IHDR chunk */
-PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length));
-PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length));
-
-#ifdef PNG_READ_bKGD_SUPPORTED
-PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_cHRM_SUPPORTED
-PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_gAMA_SUPPORTED
-PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_hIST_SUPPORTED
-PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_iCCP_SUPPORTED
-extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length));
-#endif /* PNG_READ_iCCP_SUPPORTED */
-
-#ifdef PNG_READ_iTXt_SUPPORTED
-PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_oFFs_SUPPORTED
-PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_pCAL_SUPPORTED
-PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_pHYs_SUPPORTED
-PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_sBIT_SUPPORTED
-PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_sCAL_SUPPORTED
-PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_sPLT_SUPPORTED
-extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif /* PNG_READ_sPLT_SUPPORTED */
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_tEXt_SUPPORTED
-PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_tIME_SUPPORTED
-PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_tRNS_SUPPORTED
-PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_READ_zTXt_SUPPORTED
-PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-#endif
-
-PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_uint_32 length)) PNG_PRIVATE;
-
-PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
-   png_bytep chunk_name)) PNG_PRIVATE;
-
-/* Handle the transformations for reading and writing */
-PNG_EXTERN void png_do_read_transformations
-   PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_do_write_transformations
-   PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-PNG_EXTERN void png_init_read_transformations
-   PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
-   png_uint_32 length)) PNG_PRIVATE;
-PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
-   png_bytep buffer, png_size_t buffer_length)) PNG_PRIVATE;
-PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
-   png_bytep buffer, png_size_t buffer_length)) PNG_PRIVATE;
-PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_uint_32 length)) PNG_PRIVATE;
-PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr,
-   png_bytep row)) PNG_PRIVATE;
-PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-PNG_EXTERN void png_read_push_finish_row
-   PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-#ifdef PNG_READ_tEXt_SUPPORTED
-PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_uint_32 length)) PNG_PRIVATE;
-PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-#endif
-#ifdef PNG_READ_zTXt_SUPPORTED
-PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_uint_32 length)) PNG_PRIVATE;
-PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-#endif
-#ifdef PNG_READ_iTXt_SUPPORTED
-PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_uint_32 length)) PNG_PRIVATE;
-PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
-   png_infop info_ptr)) PNG_PRIVATE;
-#endif
-
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
-   png_bytep row)) PNG_PRIVATE;
-PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
-   png_bytep row)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-#ifdef PNG_MMX_CODE_SUPPORTED
-/* png.c */ /* PRIVATE */
-PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-#endif
-#endif
-
-
-/* The following six functions will be exported in libpng-1.4.0. */
-#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
-PNG_EXTERN png_uint_32 png_get_pixels_per_inch PNGARG((png_structp png_ptr,
-png_infop info_ptr));
-
-PNG_EXTERN png_uint_32 png_get_x_pixels_per_inch PNGARG((png_structp png_ptr,
-png_infop info_ptr));
-
-PNG_EXTERN png_uint_32 png_get_y_pixels_per_inch PNGARG((png_structp png_ptr,
-png_infop info_ptr));
-
-PNG_EXTERN float png_get_x_offset_inches PNGARG((png_structp png_ptr,
-png_infop info_ptr));
-
-PNG_EXTERN float png_get_y_offset_inches PNGARG((png_structp png_ptr,
-png_infop info_ptr));
-
-#ifdef PNG_pHYs_SUPPORTED
-PNG_EXTERN 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 */
-
-/* Read the chunk header (length + type name) */
-PNG_EXTERN png_uint_32 png_read_chunk_header
-   PNGARG((png_structp png_ptr)) PNG_PRIVATE;
-
-/* Added at libpng version 1.2.34 */
-#ifdef PNG_cHRM_SUPPORTED
-PNG_EXTERN int png_check_cHRM_fixed PNGARG((png_structp png_ptr,
-   png_fixed_point int_white_x, png_fixed_point int_white_y,
-   png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
-   int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
-   png_fixed_point int_blue_y)) PNG_PRIVATE;
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-#ifdef PNG_CHECK_cHRM_SUPPORTED
-/* Added at libpng version 1.2.34 */
-PNG_EXTERN void png_64bit_product PNGARG((long v1, long v2,
-   unsigned long *hi_product, unsigned long *lo_product)) PNG_PRIVATE;
-#endif
-#endif
-
-/* Added at libpng version 1.2.41 */
-PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr,
-   png_uint_32 width, png_uint_32 height, int bit_depth,
-   int color_type, int interlace_type, int compression_type,
-   int filter_type)) PNG_PRIVATE;
-
-/* Added at libpng version 1.2.41 */
-PNG_EXTERN png_voidp png_calloc PNGARG((png_structp png_ptr,
-   png_uint_32 size));
-
-
-/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
-
-#endif /* PNG_INTERNAL */
+PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image,
+   const char *file_name));
+   /* The named file is opened for read and the image header is filled in
+    * from the PNG header in the file.
+    */
+
+PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image,
+   FILE* file));
+   /* The PNG header is read from the stdio FILE object. */
+#endif /* STDIO */
+
+PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image,
+   png_const_voidp memory, png_size_t size));
+   /* The PNG header is read from the given memory buffer. */
+
+PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image,
+   png_const_colorp background, void *buffer, png_int_32 row_stride,
+   void *colormap));
+   /* Finish reading the image into the supplied buffer and clean up the
+    * png_image structure.
+    *
+    * row_stride is the step, in byte or 2-byte units as appropriate,
+    * between adjacent rows.  A positive stride indicates that the top-most row
+    * is first in the buffer - the normal top-down arrangement.  A negative
+    * stride indicates that the bottom-most row is first in the buffer.
+    *
+    * background need only be supplied if an alpha channel must be removed from
+    * a png_byte format and the removal is to be done by compositing on a solid
+    * color; otherwise it may be NULL and any composition will be done directly
+    * onto the buffer.  The value is an sRGB color to use for the background,
+    * for grayscale output the green channel is used.
+    *
+    * background must be supplied when an alpha channel must be removed from a
+    * single byte color-mapped output format, in other words if:
+    *
+    * 1) The original format from png_image_begin_read_from_* had
+    *    PNG_FORMAT_FLAG_ALPHA set.
+    * 2) The format set by the application does not.
+    * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and
+    *    PNG_FORMAT_FLAG_LINEAR *not* set.
+    *
+    * For linear output removing the alpha channel is always done by compositing
+    * on black and background is ignored.
+    *
+    * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set.  It must
+    * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE.
+    * image->colormap_entries will be updated to the actual number of entries
+    * written to the colormap; this may be less than the original value.
+    */
+
+PNG_EXPORT(238, void, png_image_free, (png_imagep image));
+   /* Free any data allocated by libpng in image->opaque, setting the pointer to
+    * NULL.  May be called at any time after the structure is initialized.
+    */
+#endif /* SIMPLIFIED_READ */
+
+#ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
+/* WRITE APIS
+ * ----------
+ * For write you must initialize a png_image structure to describe the image to
+ * be written.  To do this use memset to set the whole structure to 0 then
+ * initialize fields describing your image.
+ *
+ * version: must be set to PNG_IMAGE_VERSION
+ * opaque: must be initialized to NULL
+ * width: image width in pixels
+ * height: image height in rows
+ * format: the format of the data (image and color-map) you wish to write
+ * flags: set to 0 unless one of the defined flags applies; set
+ *    PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB
+ *    values do not correspond to the colors in sRGB.
+ * colormap_entries: set to the number of entries in the color-map (0 to 256)
+ */
+#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
+PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image,
+   const char *file, int convert_to_8bit, const void *buffer,
+   png_int_32 row_stride, const void *colormap));
+   /* Write the image to the named file. */
+
+PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
+   int convert_to_8_bit, const void *buffer, png_int_32 row_stride,
+   const void *colormap));
+   /* Write the image to the given (FILE*). */
+#endif /* SIMPLIFIED_WRITE_STDIO */
+
+/* With all write APIs if image is in one of the linear formats with 16-bit
+ * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG
+ * gamma encoded according to the sRGB specification, otherwise a 16-bit linear
+ * encoded PNG file is written.
+ *
+ * With color-mapped data formats the colormap parameter point to a color-map
+ * with at least image->colormap_entries encoded in the specified format.  If
+ * the format is linear the written PNG color-map will be converted to sRGB
+ * regardless of the convert_to_8_bit flag.
+ *
+ * With all APIs row_stride is handled as in the read APIs - it is the spacing
+ * from one row to the next in component sized units (1 or 2 bytes) and if
+ * negative indicates a bottom-up row layout in the buffer.  If row_stride is
+ * zero, libpng will calculate it for you from the image width and number of
+ * channels.
+ *
+ * Note that the write API does not support interlacing, sub-8-bit pixels or
+ * most ancillary chunks.  If you need to write text chunks (e.g. for copyright
+ * notices) you need to use one of the other APIs.
+ */
+
+PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory,
+   png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8_bit,
+   const void *buffer, png_int_32 row_stride, const void *colormap));
+   /* Write the image to the given memory buffer.  The function both writes the
+    * whole PNG data stream to *memory and updates *memory_bytes with the count
+    * of bytes written.
+    *
+    * 'memory' may be NULL.  In this case *memory_bytes is not read however on
+    * success the number of bytes which would have been written will still be
+    * stored in *memory_bytes.  On failure *memory_bytes will contain 0.
+    *
+    * If 'memory' is not NULL it must point to memory[*memory_bytes] of
+    * writeable memory.
+    *
+    * If the function returns success memory[*memory_bytes] (if 'memory' is not
+    * NULL) contains the written PNG data.  *memory_bytes will always be less
+    * than or equal to the original value.
+    *
+    * If the function returns false and *memory_bytes was not changed an error
+    * occured during write.  If *memory_bytes was changed, or is not 0 if
+    * 'memory' was NULL, the write would have succeeded but for the memory
+    * buffer being too small.  *memory_bytes contains the required number of
+    * bytes and will be bigger that the original value.
+    */
+
+#define png_image_write_get_memory_size(image, size, convert_to_8_bit, buffer,\
+   row_stride, colormap)\
+   png_image_write_to_memory(&(image), 0, &(size), convert_to_8_bit, buffer,\
+         row_stride, colormap)
+   /* Return the amount of memory in 'size' required to compress this image.
+    * The png_image structure 'image' must be filled in as in the above
+    * function and must not be changed before the actual write call, the buffer
+    * and all other parameters must also be identical to that in the final
+    * write call.  The 'size' variable need not be initialized.
+    *
+    * NOTE: the macro returns true/false, if false is returned 'size' will be
+    * set to zero and the write failed and probably will fail if tried again.
+    */
+
+/* You can pre-allocate the buffer by making sure it is of sufficient size
+ * regardless of the amount of compression achieved.  The buffer size will
+ * always be bigger than the original image and it will never be filled.  The
+ * following macros are provided to assist in allocating the buffer.
+ */
+#define PNG_IMAGE_DATA_SIZE(image) (PNG_IMAGE_SIZE(image)+(image).height)
+   /* The number of uncompressed bytes in the PNG byte encoding of the image;
+    * uncompressing the PNG IDAT data will give this number of bytes.
+    *
+    * NOTE: while PNG_IMAGE_SIZE cannot overflow for an image in memory this
+    * macro can because of the extra bytes used in the PNG byte encoding.  You
+    * need to avoid this macro if your image size approaches 2^30 in width or
+    * height.  The same goes for the remainder of these macros; they all produce
+    * bigger numbers than the actual in-memory image size.
+    */
+#ifndef PNG_ZLIB_MAX_SIZE
+#  define PNG_ZLIB_MAX_SIZE(b) ((b)+(((b)+7U)>>3)+(((b)+63U)>>6)+11U)
+   /* An upper bound on the number of compressed bytes given 'b' uncompressed
+    * bytes.  This is based on deflateBounds() in zlib; different
+    * implementations of zlib compression may conceivably produce more data so
+    * if your zlib implementation is not zlib itself redefine this macro
+    * appropriately.
+    */
+#endif
+
+#define PNG_IMAGE_COMPRESSED_SIZE_MAX(image)\
+   PNG_ZLIB_MAX_SIZE((png_alloc_size_t)PNG_IMAGE_DATA_SIZE(image))
+   /* An upper bound on the size of the data in the PNG IDAT chunks. */
+
+#define PNG_IMAGE_PNG_SIZE_MAX_(image, image_size)\
+   ((8U/*sig*/+25U/*IHDR*/+16U/*gAMA*/+44U/*cHRM*/+12U/*IEND*/+\
+    (((image).format&PNG_FORMAT_FLAG_COLORMAP)?/*colormap: PLTE, tRNS*/\
+     12U+3U*(image).colormap_entries/*PLTE data*/+\
+     (((image).format&PNG_FORMAT_FLAG_ALPHA)?\
+      12U/*tRNS*/+(image).colormap_entries:0U):0U)+\
+    12U)+(12U*((image_size)/PNG_ZBUF_SIZE))/*IDAT*/+(image_size))
+   /* A helper for the following macro; if your compiler cannot handle the
+    * following macro use this one with the result of
+    * PNG_IMAGE_COMPRESSED_SIZE_MAX(image) as the second argument (most
+    * compilers should handle this just fine.)
+    */
+
+#define PNG_IMAGE_PNG_SIZE_MAX(image)\
+   PNG_IMAGE_PNG_SIZE_MAX_(image, PNG_IMAGE_COMPRESSED_SIZE_MAX(image))
+   /* An upper bound on the total length of the PNG data stream for 'image'.
+    * The result is of type png_alloc_size_t, on 32-bit systems this may
+    * overflow even though PNG_IMAGE_DATA_SIZE does not overflow; the write will
+    * run out of buffer space but return a corrected size which should work.
+    */
+#endif /* SIMPLIFIED_WRITE */
+/*******************************************************************************
+ *  END OF SIMPLIFIED API
+ ******************************************************************************/
+#endif /* SIMPLIFIED_{READ|WRITE} */
+
+/*******************************************************************************
+ * Section 6: IMPLEMENTATION OPTIONS
+ *******************************************************************************
+ *
+ * Support for arbitrary implementation-specific optimizations.  The API allows
+ * particular options to be turned on or off.  'Option' is the number of the
+ * option and 'onoff' is 0 (off) or non-0 (on).  The value returned is given
+ * by the PNG_OPTION_ defines below.
+ *
+ * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions,
+ *           are detected at run time, however sometimes it may be impossible
+ *           to do this in user mode, in which case it is necessary to discover
+ *           the capabilities in an OS specific way.  Such capabilities are
+ *           listed here when libpng has support for them and must be turned
+ *           ON by the application if present.
+ *
+ * SOFTWARE: sometimes software optimizations actually result in performance
+ *           decrease on some architectures or systems, or with some sets of
+ *           PNG images.  'Software' options allow such optimizations to be
+ *           selected at run time.
+ */
+#ifdef PNG_SET_OPTION_SUPPORTED
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+#  define PNG_ARM_NEON   0 /* HARDWARE: ARM Neon SIMD instructions supported */
+#endif
+#define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */
+#define PNG_SKIP_sRGB_CHECK_PROFILE 4 /* SOFTWARE: Check ICC profile for sRGB */
+#define PNG_OPTION_NEXT  6 /* Next option - numbers must be even */
+
+/* Return values: NOTE: there are four values and 'off' is *not* zero */
+#define PNG_OPTION_UNSET   0 /* Unset - defaults to off */
+#define PNG_OPTION_INVALID 1 /* Option number out of range */
+#define PNG_OPTION_OFF     2
+#define PNG_OPTION_ON      3
+
+PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
+   int onoff));
+#endif /* SET_OPTION */
+
+/*******************************************************************************
+ *  END OF HARDWARE AND SOFTWARE OPTIONS
+ ******************************************************************************/
+
+/* Maintainer: Put new public prototypes here ^, in libpng.3, in project
+ * defs, and in scripts/symbols.def.
+ */
+
+/* The last ordinal number (this is the *last* one already used; the next
+ * one to use is one more than this.)
+ */
+#ifdef PNG_EXPORT_LAST_ORDINAL
+  PNG_EXPORT_LAST_ORDINAL(245);
+#endif
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif /* PNG_VERSION_INFO_ONLY */
 /* Do not put anything past this line */
 #endif /* PNG_H */