libpng/pngpriv.h
John Bowler 95e0094f85 Eliminate signed overlow in png_64bit_product
The previous version produced a signed overflow as a result of both the
& 0xffff on the most significant bits of a negative argument; this
converted (-1) into 65535 which resulted in a subsequent overflow.
Since signed overflow is undefined in C90 the code has been modified to
correctly calculate a signed result.  This requires changing the 'hi'
result parametr to a signed value.

This has been code reviewed solely by the author.  A further code review
is highly desireable.  Nevertheless the code compiles without warnings
from clang and without the prior detection of an overflow.  Since it no
longer truncates any of the intermediate values this should be enough to
ensure that it is correct.

Signed-off-by: John Bowler <jbowler@acm.org>
2016-12-26 16:29:16 -08:00

1755 lines
67 KiB
C

/* pngpriv.h - private declarations for use inside libpng
*
* Last changed in libpng 1.5.26 [December 17, 2015]
* Copyright (c) 1998-2002,2004,2006-2015 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.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
/* The symbols declared in this file (including the functions declared
* as PNG_EXTERN) are PRIVATE. They are not part of the libpng public
* interface, and are not recommended for use by regular applications.
* Some of them may become public in the future; others may stay private,
* change in an incompatible way, or even disappear.
* Although the libpng users are not forbidden to include this header,
* they should be well aware of the issues that may arise from doing so.
*/
#ifndef PNGPRIV_H
#define PNGPRIV_H
/* Feature Test Macros. The following are defined here to ensure that correctly
* implemented libraries reveal the APIs libpng needs to build and hide those
* that are not needed and potentially damaging to the compilation.
*
* Feature Test Macros must be defined before any system header is included (see
* POSIX 1003.1 2.8.2 "POSIX Symbols."
*
* These macros only have an effect if the operating system supports either
* POSIX 1003.1 or C99, or both. On other operating systems (particularly
* Windows/Visual Studio) there is no effect; the OS specific tests below are
* still required (as of 2011-05-02.)
*/
#define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
#ifndef PNG_VERSION_INFO_ONLY
/* This is required for the definition of abort(), used as a last ditch
* error handler when all else fails.
*/
#include <stdlib.h>
/* This is used to find 'offsetof', used below for alignment tests. */
#include <stddef.h>
#endif /* !PNG_VERSION_INFO_ONLY */
#define PNGLIB_BUILD /*libpng is being built, not used*/
#ifdef PNG_USER_CONFIG
# include "pngusr.h"
/* These should have been defined in pngusr.h */
# ifndef PNG_USER_PRIVATEBUILD
# define PNG_USER_PRIVATEBUILD "Custom libpng build"
# endif
# ifndef PNG_USER_DLLFNAME_POSTFIX
# define PNG_USER_DLLFNAME_POSTFIX "Cb"
# endif
#endif
/* Is this a build of a DLL where compilation of the object modules requires
* different preprocessor settings to those required for a simple library? If
* so PNG_BUILD_DLL must be set.
*
* If libpng is used inside a DLL but that DLL does not export the libpng APIs
* PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
* static library of libpng then link the DLL against that.
*/
#ifndef PNG_BUILD_DLL
# ifdef DLL_EXPORT
/* This is set by libtool when files are compiled for a DLL; libtool
* always compiles twice, even on systems where it isn't necessary. Set
* PNG_BUILD_DLL in case it is necessary:
*/
# define PNG_BUILD_DLL
# else
# ifdef _WINDLL
/* This is set by the Microsoft Visual Studio IDE in projects that
* build a DLL. It can't easily be removed from those projects (it
* isn't visible in the Visual Studio UI) so it is a fairly reliable
* indication that PNG_IMPEXP needs to be set to the DLL export
* attributes.
*/
# define PNG_BUILD_DLL
# else
# ifdef __DLL__
/* This is set by the Borland C system when compiling for a DLL
* (as above.)
*/
# define PNG_BUILD_DLL
# else
/* Add additional compiler cases here. */
# endif
# endif
# endif
#endif /* Setting PNG_BUILD_DLL if required */
/* See pngconf.h for more details: the builder of the library may set this on
* the command line to the right thing for the specific compilation system or it
* may be automagically set above (at present we know of no system where it does
* need to be set on the command line.)
*
* PNG_IMPEXP must be set here when building the library to prevent pngconf.h
* setting it to the "import" setting for a DLL build.
*/
#ifndef PNG_IMPEXP
# ifdef PNG_BUILD_DLL
# define PNG_IMPEXP PNG_DLL_EXPORT
# else
/* Not building a DLL, or the DLL doesn't require specific export
* definitions.
*/
# define PNG_IMPEXP
# endif
#endif
/* No warnings for private or deprecated functions in the build: */
#ifndef PNG_DEPRECATED
# define PNG_DEPRECATED
#endif
#ifndef PNG_PRIVATE
# define PNG_PRIVATE
#endif
#include "png.h"
/* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
#ifndef PNG_DLL_EXPORT
# define PNG_DLL_EXPORT
#endif
/* Compile time options.
* =====================
* In a multi-arch build the compiler may compile the code several times for the
* same object module, producing different binaries for different architectures.
* When this happens configure-time setting of the target host options cannot be
* done and this interferes with the handling of the ARM NEON optimizations, and
* possibly other similar optimizations. Put additional tests here; in general
* this is needed when the same option can be changed at both compile time and
* run time depending on the target OS (i.e. iOS vs Android.)
*
* NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
* this is not possible with certain compilers (Oracle SUN OS CC), as a result
* it is necessary to ensure that all extern functions that *might* be used
* regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__
* below is one example of this behavior because it is controlled by the
* presence or not of -mfpu=neon on the GCC command line, it is possible to do
* this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
* do this.
*/
#ifndef PNG_ARM_NEON_OPT
/* ARM NEON optimizations are being controlled by the compiler settings,
* typically the target FPU. If the FPU has been set to NEON (-mfpu=neon
* with GCC) then the compiler will define __ARM_NEON__ and we can rely
* unconditionally on NEON instructions not crashing, otherwise we must
* disable use of NEON instructions.
*
* NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they
* can only be turned on automatically if that is supported too. If
* PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail
* to compile with an appropriate #error if ALIGNED_MEMORY has been turned
* off.
*/
# if defined(__ARM_NEON__) && defined(PNG_ALIGNED_MEMORY_SUPPORTED)
# define PNG_ARM_NEON_OPT 2
# else
# define PNG_ARM_NEON_OPT 0
# endif
#endif
#if PNG_ARM_NEON_OPT > 0
/* NEON optimizations are to be at least considered by libpng, so enable the
* callbacks to do this.
*/
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
#endif
/* SECURITY and SAFETY:
*
* By default libpng is built without any internal limits on image size,
* individual heap (png_malloc) allocations or the total amount of memory used.
* If PNG_SAFE_LIMITS_SUPPORTED is defined, however, the limits below are used
* (unless individually overridden). These limits are believed to be fairly
* safe, but builders of secure systems should verify the values against the
* real system capabilities.
*/
/* config.h is created by and PNG_CONFIGURE_LIBPNG is set by the "configure"
* script. We may need it here to get the correct configuration on things
* like limits.
*/
#ifdef PNG_CONFIGURE_LIBPNG
# ifdef HAVE_CONFIG_H
# include "config.h"
# endif
#endif
/* SECURITY and SAFETY:
*
* libpng is built with support for internal limits on image dimensions and
* memory usage. These are documented in scripts/pnglibconf.dfa of the
* source and recorded in the machine generated header file pnglibconf.h.
*/
/* If you are running on a machine where you cannot allocate more
* than 64K of memory at once, uncomment this. While libpng will not
* normally need that much memory in a chunk (unless you load up a very
* large file), zlib needs to know how big of a chunk it can use, and
* libpng thus makes sure to check any memory allocation to verify it
* will fit into memory.
*
* zlib provides 'MAXSEG_64K' which, if defined, indicates the
* same limit and pngconf.h (already included) sets the limit
* if certain operating systems are detected.
*/
#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
# define PNG_MAX_MALLOC_64K
#endif
/* Moved to pngpriv.h at libpng-1.5.0 */
/* NOTE: some of these may have been used in external applications as
* these definitions were exposed in pngconf.h prior to 1.5.
*/
#ifndef PNG_UNUSED
/* Unused formal parameter warnings are silenced using the following macro
* which is expected to have no bad effects on performance (optimizing
* compilers will probably remove it entirely). Note that if you replace
* it with something other than whitespace, you must include the terminating
* semicolon.
*/
# define PNG_UNUSED(param) (void)param;
#endif
/* Just a little check that someone hasn't tried to define something
* contradictory.
*/
#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
# undef PNG_ZBUF_SIZE
# define PNG_ZBUF_SIZE 65536L
#endif
/* PNG_STATIC is used to mark internal file scope functions if they need to be
* accessed for implementation tests (see the code in tests/?*).
*/
#ifndef PNG_STATIC
# define PNG_STATIC static
#endif
/* C99 restrict is used where possible, to do this 'restrict' is defined as
* empty if we can't be sure it is supported. configure builds have already
* done this work.
*/
#ifdef PNG_CONFIGURE_LIBPNG
# define PNG_RESTRICT restrict
#else
/* Modern compilers support restrict, but assume not for anything not
* recognized here:
*/
# if defined(__GNUC__) || defined(_MSC_VER) || defined(__WATCOMC__)
# define PNG_RESTRICT restrict
# else
# define PNG_RESTRICT
# endif
#endif
/* If warnings or errors are turned off the code is disabled or redirected here.
* From 1.5.4 functions have been added to allow very limited formatting of
* error and warning messages - this code will also be disabled here.
*/
#ifdef PNG_WARNINGS_SUPPORTED
# define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
#else
# define png_warning_parameter(p,number,string) ((void)0)
# define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
# define png_warning_parameter_signed(p,number,format,value) ((void)0)
# define png_formatted_warning(pp,p,message) ((void)(pp))
# define PNG_WARNING_PARAMETERS(p)
#endif
#ifndef PNG_ERROR_TEXT_SUPPORTED
# define png_fixed_error(s1,s2) png_err(s1)
#endif
/* C allows up-casts from (void*) to any pointer and (const void*) to any
* pointer to a const object. C++ regards this as a type error and requires an
* explicit, static, cast and provides the static_cast<> rune to ensure that
* const is not cast away.
*/
#ifdef __cplusplus
# define png_voidcast(type, value) static_cast<type>(value)
#else
# define png_voidcast(type, value) (value)
#endif /* __cplusplus */
#ifndef PNG_EXTERN
/* The functions exported by PNG_EXTERN are internal functions, which
* aren't usually used outside the library (as far as I know), so it is
* debatable if they should be exported at all. In the future, when it
* is possible to have run-time registry of chunk-handling functions,
* some of these might be made available again.
*
* 1.5.7: turned the use of 'extern' back on, since it is localized to pngpriv.h
* it should be safe now (it is unclear why it was turned off.)
*/
# define PNG_EXTERN extern
#endif
/* Some fixed point APIs are still required even if not exported because
* they get used by the corresponding floating point APIs. This magic
* deals with this:
*/
#ifdef PNG_FIXED_POINT_SUPPORTED
# define PNGFAPI PNGAPI
#else
# define PNGFAPI /* PRIVATE */
#endif
#ifndef PNG_VERSION_INFO_ONLY
/* Other defines specific to compilers can go here. Try to keep
* them inside an appropriate ifdef/endif pair for portability.
*/
#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
/* png.c requires the following ANSI-C constants if the conversion of
* floating point to ASCII is implemented therein:
*
* DBL_DIG Maximum number of decimal digits (can be set to any constant)
* DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
* DBL_MAX Maximum floating point number (can be set to an arbitrary value)
*/
# include <float.h>
# if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
/* We need to check that <math.h> hasn't already been included earlier
* as it seems it doesn't agree with <fp.h>, yet we should really use
* <fp.h> if possible.
*/
# if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
# include <fp.h>
# endif
# else
# include <math.h>
# endif
# if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
/* Amiga SAS/C: We must include builtin FPU functions when compiling using
* MATH=68881
*/
# include <m68881.h>
# endif
#endif
/* This provides the non-ANSI (far) memory allocation routines. */
#if defined(__TURBOC__) && defined(__MSDOS__)
# include <mem.h>
# include <alloc.h>
#endif
#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
defined(_WIN32) || defined(__WIN32__)
# include <windows.h> /* defines _WINDOWS_ macro */
#endif
#endif /* !PNG_VERSION_INFO_ONLY */
/* Moved here around 1.5.0beta36 from pngconf.h */
/* Users may want to use these so they are not private. Any library
* functions that are passed far data must be model-independent.
*/
/* Memory model/platform independent fns */
#ifndef PNG_ABORT
# ifdef _WINDOWS_
# define PNG_ABORT() ExitProcess(0)
# else
# define PNG_ABORT() abort()
# endif
#endif
#ifdef USE_FAR_KEYWORD
/* Use this to make far-to-near assignments */
# define CHECK 1
# define NOCHECK 0
# define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
# define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
# define png_strlen _fstrlen
# define png_memcmp _fmemcmp /* SJT: added */
# define png_memcpy _fmemcpy
# define png_memset _fmemset
#else
# ifdef _WINDOWS_ /* Favor Windows over C runtime fns */
# define CVT_PTR(ptr) (ptr)
# define CVT_PTR_NOCHECK(ptr) (ptr)
# define png_strlen lstrlenA
# define png_memcmp memcmp
# define png_memcpy memcpy
# define png_memset memset
# else
# define CVT_PTR(ptr) (ptr)
# define CVT_PTR_NOCHECK(ptr) (ptr)
# define png_strlen strlen
# define png_memcmp memcmp /* SJT: added */
# define png_memcpy memcpy
# define png_memset memset
# endif
#endif
/* These macros may need to be architecture dependent. */
#define PNG_ALIGN_NONE 0 /* do not use data alignment */
#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
#ifdef offsetof
# define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
#else
# define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
#endif
#define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
#ifndef PNG_ALIGN_TYPE
/* Default to using aligned access optimizations and requiring alignment to a
* multiple of the data type size. Override in a compiler specific fashion
* if necessary by inserting tests here:
*/
# define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
#endif
#if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
/* This is used because in some compiler implementations non-aligned
* structure members are supported, so the offsetof approach below fails.
* Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
* is good for performance. Do not do this unless you have tested the result
* and understand it.
*/
# define png_alignof(type) (sizeof (type))
#else
# if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
# define png_alignof(type) offsetof(struct{char c; type t;}, t)
# else
# if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
# define png_alignof(type) (1)
# endif
/* Else leave png_alignof undefined to prevent use thereof */
# endif
#endif
/* This implicitly assumes alignment is always to a power of 2. */
#ifdef png_alignof
# define png_isaligned(ptr, type)\
((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
#else
# define png_isaligned(ptr, type) 0
#endif
/* End of memory model/platform independent support */
/* End of 1.5.0beta36 move from pngconf.h */
/* CONSTANTS and UTILITY MACROS
* These are used internally by libpng and not exposed in the API
*/
/* Various modes of operation. Note that after an init, mode is set to
* zero automatically when the structure is created. Three of these
* are defined in png.h because they need to be visible to applications
* that call png_set_unknown_chunk().
*/
/* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */
/* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */
#define PNG_HAVE_IDAT 0x04
/* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */
#define PNG_HAVE_IEND 0x10
#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 */
#define PNG_HAVE_iCCP 0x4000
/* 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_QUANTIZE 0x0040
#define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */
#define PNG_BACKGROUND_EXPAND 0x0100
#define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */
#define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */
#define PNG_RGBA 0x0800
#define PNG_EXPAND 0x1000
#define PNG_GAMMA 0x2000
#define PNG_GRAY_TO_RGB 0x4000
#define PNG_FILLER 0x8000
#define PNG_PACKSWAP 0x10000
#define PNG_SWAP_ALPHA 0x20000
#define PNG_STRIP_ALPHA 0x40000
#define PNG_INVERT_ALPHA 0x80000
#define PNG_USER_TRANSFORM 0x100000
#define PNG_RGB_TO_GRAY_ERR 0x200000
#define PNG_RGB_TO_GRAY_WARN 0x400000
#define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
#define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */
#define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */
#define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */
#define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */
/* 0x8000000 unused */
/* 0x10000000 unused */
/* 0x20000000 unused */
/* 0x40000000 unused */
/* Flags for png_create_struct */
#define PNG_STRUCT_PNG 0x0001
#define PNG_STRUCT_INFO 0x0002
/* 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_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */
#define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */
#define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */
#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000
#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000
#define PNG_FLAG_LIBRARY_MISMATCH 0x20000
#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000
#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000
#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000
#define PNG_FLAG_ZSTREAM_PROGRESSIVE 0x200000
/* 0x400000 unused */
#define PNG_FLAG_BENIGN_ERRORS_WARN 0x800000 /* Added to libpng-1.4.0 */
#define PNG_FLAG_ZTXT_CUSTOM_STRATEGY 0x1000000 /* 5 lines added */
#define PNG_FLAG_ZTXT_CUSTOM_LEVEL 0x2000000 /* to libpng-1.5.4 */
#define PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL 0x4000000
#define PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS 0x8000000
#define PNG_FLAG_ZTXT_CUSTOM_METHOD 0x10000000
/* 0x20000000 unused */
/* 0x40000000 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)
/* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
* can handle at once. This type need be no larger than 16 bits (so maximum of
* 65535), this define allows us to discover how big it is, but limited by the
* maximuum for png_size_t. The value can be overriden in a library build
* (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably
* lower value (e.g. 255 works). A lower value may help memory usage (slightly)
* and may even improve performance on some systems (and degrade it on others.)
*/
#ifndef ZLIB_IO_MAX
# define ZLIB_IO_MAX ((uInt)-1)
#endif
/* 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 ? \
((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
(( ((png_size_t)(width) * ((png_size_t)(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) )
/* Conversions between fixed and floating point, only defined if
* required (to make sure the code doesn't accidentally use float
* when it is supposedly disabled.)
*/
#ifdef PNG_FLOATING_POINT_SUPPORTED
/* The floating point conversion can't overflow, though it can and
* does lose accuracy relative to the original fixed point value.
* In practice this doesn't matter because png_fixed_point only
* stores numbers with very low precision. The png_ptr and s
* arguments are unused by default but are there in case error
* checking becomes a requirement.
*/
#define png_float(png_ptr, fixed, s) (.00001 * (fixed))
/* The fixed point conversion performs range checking and evaluates
* its argument multiple times, so must be used with care. The
* range checking uses the PNG specification values for a signed
* 32 bit fixed point value except that the values are deliberately
* rounded-to-zero to an integral value - 21474 (21474.83 is roughly
* (2^31-1) * 100000). 's' is a string that describes the value being
* converted.
*
* NOTE: this macro will raise a png_error if the range check fails,
* therefore it is normally only appropriate to use this on values
* that come from API calls or other sources where an out of range
* error indicates a programming error, not a data error!
*
* NOTE: by default this is off - the macro is not used - because the
* function call saves a lot of code.
*/
#ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
#define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
#else
#ifndef PNG_VERSION_INFO_ONLY
PNG_EXTERN png_fixed_point png_fixed PNGARG((png_structp png_ptr, double fp,
png_const_charp text));
#endif /* !PNG_VERSION_INFO_ONLY */
#endif
#endif
/* Constants for known chunk types. If you need to add a chunk, define the name
* here. For historical reasons these constants have the form png_<name>; i.e.
* the prefix is lower case. Please use decimal values as the parameters to
* match the ISO PNG specification and to avoid relying on the C locale
* interpretation of character values.
*
* Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
* are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
* to be generated if required.
*
* PNG_32b correctly produces a value shifted by up to 24 bits, even on
* architectures where (int) is only 16 bits.
*/
#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
#define PNG_CHUNK(b1,b2,b3,b4) \
(PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
#define png_IHDR PNG_CHUNK( 73, 72, 68, 82)
#define png_IDAT PNG_CHUNK( 73, 68, 65, 84)
#define png_IEND PNG_CHUNK( 73, 69, 78, 68)
#define png_PLTE PNG_CHUNK( 80, 76, 84, 69)
#define png_bKGD PNG_CHUNK( 98, 75, 71, 68)
#define png_cHRM PNG_CHUNK( 99, 72, 82, 77)
#define png_gAMA PNG_CHUNK(103, 65, 77, 65)
#define png_hIST PNG_CHUNK(104, 73, 83, 84)
#define png_iCCP PNG_CHUNK(105, 67, 67, 80)
#define png_iTXt PNG_CHUNK(105, 84, 88, 116)
#define png_oFFs PNG_CHUNK(111, 70, 70, 115)
#define png_pCAL PNG_CHUNK(112, 67, 65, 76)
#define png_sCAL PNG_CHUNK(115, 67, 65, 76)
#define png_pHYs PNG_CHUNK(112, 72, 89, 115)
#define png_sBIT PNG_CHUNK(115, 66, 73, 84)
#define png_sPLT PNG_CHUNK(115, 80, 76, 84)
#define png_sRGB PNG_CHUNK(115, 82, 71, 66)
#define png_sTER PNG_CHUNK(115, 84, 69, 82)
#define png_tEXt PNG_CHUNK(116, 69, 88, 116)
#define png_tIME PNG_CHUNK(116, 73, 77, 69)
#define png_tRNS PNG_CHUNK(116, 82, 78, 83)
#define png_zTXt PNG_CHUNK(122, 84, 88, 116)
/* The following will work on (signed char*) strings, whereas the get_uint_32
* macro will fail on top-bit-set values because of the sign extension.
*/
#define PNG_CHUNK_FROM_STRING(s)\
PNG_CHUNK(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
* signed and the argument is a (char[]) This macro will fail miserably on
* systems where (char) is more than 8 bits.
*/
#define PNG_STRING_FROM_CHUNK(s,c)\
(void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
/* Do the same but terminate with a null character. */
#define PNG_CSTRING_FROM_CHUNK(s,c)\
(void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
/* Test on flag values as defined in the spec (section 5.4): */
#define PNG_CHUNK_ANCILLIARY(c) (1 & ((c) >> 29))
#define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLIARY(c))
#define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
#define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
/* Gamma values (new at libpng-1.5.4): */
#define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
#define PNG_GAMMA_MAC_INVERSE 65909
#define PNG_GAMMA_sRGB_INVERSE 45455
/* Almost everything below is C specific; the #defines above can be used in
* non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
*/
#ifndef PNG_VERSION_INFO_ONLY
#include "pngstruct.h"
#include "pnginfo.h"
/* This is used for 16 bit gamma tables -- only the top level pointers are
* const; this could be changed:
*/
typedef const png_uint_16p * png_const_uint_16pp;
/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/* These 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.
*/
/* Check the user version string for compatibility, returns false if the version
* numbers aren't compatible.
*/
PNG_EXTERN int png_user_version_check(png_structp png_ptr,
png_const_charp user_png_ver);
/* Allocate memory for an internal libpng struct */
PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct,PNGARG((int type)),
PNG_ALLOCATED);
/* Free memory from internal libpng struct */
PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct_2,
PNGARG((int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)),
PNG_ALLOCATED);
PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
png_free_ptr free_fn, png_voidp mem_ptr));
/* Free any memory that info_ptr points to and reset struct. */
PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* Function to allocate memory for zlib. PNGAPI is disallowed. */
PNG_EXTERN PNG_FUNCTION(voidpf,png_zalloc,PNGARG((voidpf png_ptr, uInt items,
uInt size)),PNG_ALLOCATED);
/* Function to free memory for zlib. PNGAPI is disallowed. */
PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
/* Next four functions are used internally as callbacks. PNGCBAPI is required
* but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
* PNGCBAPI at 1.5.0
*/
PNG_EXTERN void PNGCBAPI png_default_read_data PNGARG((png_structp png_ptr,
png_bytep data, png_size_t length));
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
PNG_EXTERN void PNGCBAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
png_bytep buffer, png_size_t length));
#endif
PNG_EXTERN void PNGCBAPI png_default_write_data PNGARG((png_structp png_ptr,
png_bytep data, png_size_t length));
#ifdef PNG_WRITE_FLUSH_SUPPORTED
# ifdef PNG_STDIO_SUPPORTED
PNG_EXTERN void PNGCBAPI png_default_flush PNGARG((png_structp png_ptr));
# endif
#endif
/* Reset the CRC variable */
PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
/* Write the "data" buffer to whatever output you are using */
PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr,
png_const_bytep data, png_size_t length));
/* Read and check the PNG file signature */
PNG_EXTERN void png_read_sig PNGARG((png_structp png_ptr, png_infop info_ptr));
/* Read the chunk header (length + type name) */
PNG_EXTERN png_uint_32 png_read_chunk_header PNGARG((png_structp png_ptr));
/* Read data from whatever input you are using into the "data" buffer */
PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
png_size_t length));
/* Read bytes into buf, and update png_ptr->crc */
PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
png_size_t length));
/* Decompress data in a chunk that uses compression */
#if defined(PNG_READ_COMPRESSED_TEXT_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));
#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));
/* Read the CRC from the file and compare it to the libpng calculated CRC */
PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
/* Calculate the CRC over a section of data. Note that we are only
* passing a maximum of 64K on systems that have this as a memory limit,
* since this is the maximum buffer size we can specify.
*/
PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr,
png_const_bytep ptr, png_size_t length));
#ifdef PNG_WRITE_FLUSH_SUPPORTED
PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
#endif
/* 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_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr,
png_const_colorp palette, png_uint_32 num_pal));
PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
png_size_t length));
PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
#ifdef PNG_WRITE_gAMA_SUPPORTED
# ifdef PNG_FLOATING_POINT_SUPPORTED
PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
# endif
PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr,
png_fixed_point file_gamma));
#endif
#ifdef PNG_WRITE_sBIT_SUPPORTED
PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr,
png_const_color_8p sbit, int color_type));
#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));
# endif
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));
#endif
#ifdef PNG_WRITE_sRGB_SUPPORTED
PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
int intent));
#endif
#ifdef PNG_WRITE_iCCP_SUPPORTED
PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
png_const_charp name, int compression_type,
png_const_charp profile, int proflen));
/* 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_const_sPLT_tp palette));
#endif
#ifdef PNG_WRITE_tRNS_SUPPORTED
PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr,
png_const_bytep trans, png_const_color_16p values, int number,
int color_type));
#endif
#ifdef PNG_WRITE_bKGD_SUPPORTED
PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
png_const_color_16p values, int color_type));
#endif
#ifdef PNG_WRITE_hIST_SUPPORTED
PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr,
png_const_uint_16p hist, int num_hist));
#endif
#ifdef PNG_WRITE_tEXt_SUPPORTED
PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_const_charp key,
png_const_charp text, png_size_t text_len));
#endif
#ifdef PNG_WRITE_zTXt_SUPPORTED
PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_const_charp key,
png_const_charp text, png_size_t text_len, int compression));
#endif
#ifdef PNG_WRITE_iTXt_SUPPORTED
PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
int compression, png_const_charp key, png_const_charp lang,
png_const_charp lang_key, png_const_charp text));
#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_const_textp text_ptr, int num_text));
#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));
#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_const_charp units, png_charpp params));
#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));
#endif
#ifdef PNG_WRITE_tIME_SUPPORTED
PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
png_const_timep mod_time));
#endif
#ifdef PNG_WRITE_sCAL_SUPPORTED
PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
int unit, png_const_charp width, png_const_charp height));
#endif
/* Called when finished processing a row of data */
PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
/* Internal use only. Called before first row of data */
PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
/* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
* array of png_ptr->width pixels. If the image is not interlaced or this
* is the final pass this just does a png_memcpy, otherwise the "display" flag
* is used to determine whether to copy pixels that are not in the current pass.
*
* Because 'png_do_read_interlace' (below) replicates pixels this allows this
* function to achieve the documented 'blocky' appearance during interlaced read
* if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
* are not changed if they are not in the current pass, when display is 0.
*
* 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
*
* The API always reads from the png_struct row buffer and always assumes that
* it is full width (png_do_read_interlace has already been called.)
*
* This function is only ever used to write to row buffers provided by the
* caller of the relevant libpng API and the row must have already been
* transformed by the read transformations.
*
* The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
* bitmasks for use within the code, otherwise runtime generated masks are used.
* The default is compile time masks.
*/
#ifndef PNG_USE_COMPILE_TIME_MASKS
# define PNG_USE_COMPILE_TIME_MASKS 1
#endif
PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
int display));
#ifdef PNG_READ_INTERLACING_SUPPORTED
/* Expand an interlaced row: the 'row_info' describes the pass data that has
* been read in and must correspond to the pixels in 'row', the pixels are
* expanded (moved apart) in 'row' to match the final layout, when doing this
* the pixels are *replicated* to the intervening space. This is essential for
* the correct operation of png_combine_row, above.
*/
PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
png_bytep row, int pass, png_uint_32 transformations));
#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));
#endif
/* Unfilter a row: check the filter value before calling this, there is no point
* calling it for PNG_FILTER_VALUE_NONE.
*/
PNG_EXTERN void png_read_filter_row PNGARG((png_structp pp, png_row_infop
row_info, png_bytep row, png_const_bytep prev_row, int filter));
PNG_EXTERN void png_read_filter_row_up_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
PNG_EXTERN void png_read_filter_row_sub3_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
PNG_EXTERN void png_read_filter_row_sub4_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
PNG_EXTERN void png_read_filter_row_avg3_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
PNG_EXTERN void png_read_filter_row_avg4_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
PNG_EXTERN void png_read_filter_row_paeth3_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
PNG_EXTERN void png_read_filter_row_paeth4_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
/* 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));
/* 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));
#ifdef PNG_READ_TRANSFORMS_SUPPORTED
/* Optional call to update the users info structure */
PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
png_infop info_ptr));
#endif
/* 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));
#endif
#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
PNG_EXTERN void png_do_strip_channel PNGARG((png_row_infop row_info,
png_bytep row, int at_start));
#endif
#ifdef PNG_16BIT_SUPPORTED
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#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));
#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));
#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));
#endif
#ifdef PNG_READ_PACK_SUPPORTED
PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#ifdef PNG_READ_SHIFT_SUPPORTED
PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info,
png_bytep row, png_const_color_8p sig_bits));
#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));
#endif
#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
PNG_EXTERN void png_do_scale_16_to_8 PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#ifdef PNG_READ_QUANTIZE_SUPPORTED
PNG_EXTERN void png_do_quantize PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep palette_lookup,
png_const_bytep quantize_lookup));
# ifdef PNG_CORRECT_PALETTE_SUPPORTED
PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
png_colorp palette, int num_palette));
# 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));
#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));
#endif
#ifdef PNG_WRITE_SHIFT_SUPPORTED
PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info,
png_bytep row, png_const_color_8p bit_depth));
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
defined(PNG_READ_ALPHA_MODE_SUPPORTED)
PNG_EXTERN void png_do_compose PNGARG((png_row_infop row_info,
png_bytep row, png_structp png_ptr));
#endif
#ifdef PNG_READ_GAMMA_SUPPORTED
PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info,
png_bytep row, png_structp png_ptr));
#endif
#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
PNG_EXTERN void png_do_encode_alpha PNGARG((png_row_infop row_info,
png_bytep row, png_structp png_ptr));
#endif
#ifdef PNG_READ_EXPAND_SUPPORTED
PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
png_bytep row, png_const_colorp palette, png_const_bytep trans,
int num_trans));
PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
png_bytep row, png_const_color_16p trans_color));
#endif
#ifdef PNG_READ_EXPAND_16_SUPPORTED
PNG_EXTERN void png_do_expand_16 PNGARG((png_row_infop row_info,
png_bytep row));
#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_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));
#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));
#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));
#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));
#endif
#ifdef PNG_READ_iCCP_SUPPORTED
PNG_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));
#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));
#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));
#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));
#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));
#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));
#endif
#ifdef PNG_READ_sPLT_SUPPORTED
PNG_EXTERN void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#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));
#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));
#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));
#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));
#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));
#endif
PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 length));
PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
png_uint_32 chunk_name));
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
/* Exactly as png_handle_as_unknown() except that the argument is a 32-bit chunk
* name, not a string.
*/
PNG_EXTERN int png_chunk_unknown_handling PNGARG((png_structp png_ptr,
png_uint_32 chunk_name));
#endif
/* Handle the transformations for reading and writing */
#ifdef PNG_READ_TRANSFORMS_SUPPORTED
PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr,
png_row_infop row_info));
#endif
#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr,
png_row_infop row_info));
#endif
#ifdef PNG_READ_TRANSFORMS_SUPPORTED
PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
#endif
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
png_bytep buffer, png_size_t buffer_length));
PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
png_bytep buffer, png_size_t buffer_length));
PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 length));
PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
# 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_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
png_infop info_ptr));
# 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_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
png_infop info_ptr));
# 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_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
png_infop info_ptr));
# 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_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
png_bytep row));
#endif
/* Added at libpng version 1.4.0 */
#ifdef PNG_CHECK_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));
#endif
#ifdef PNG_cHRM_SUPPORTED
/* Added at libpng version 1.5.5 */
typedef struct png_xy
{
png_fixed_point redx, redy;
png_fixed_point greenx, greeny;
png_fixed_point bluex, bluey;
png_fixed_point whitex, whitey;
} png_xy;
typedef struct png_XYZ
{
png_fixed_point redX, redY, redZ;
png_fixed_point greenX, greenY, greenZ;
png_fixed_point blueX, blueY, blueZ;
} png_XYZ;
/* The conversion APIs return 0 on success, non-zero on a parameter error. They
* allow conversion between the above representations of a color encoding. When
* converting from XYZ end points to chromaticities the absolute magnitude of
* the end points is lost, when converting back the sum of the Y values of the
* three end points will be 1.0
*/
PNG_EXTERN int png_xy_from_XYZ PNGARG((png_xy *xy, png_XYZ XYZ));
PNG_EXTERN int png_XYZ_from_xy PNGARG((png_XYZ *XYZ, png_xy xy));
PNG_EXTERN int png_XYZ_from_xy_checked PNGARG((png_structp png_ptr,
png_XYZ *XYZ, png_xy xy));
#endif
/* Added at libpng version 1.4.0 */
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));
/* Added at libpng version 1.5.10 */
#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
PNG_EXTERN void png_do_check_palette_indexes PNGARG((png_structp png_ptr,
png_row_infop row_info));
#endif
/* Free all memory used by the read (old method - NOT DLL EXPORTED) */
PNG_EXTERN void png_read_destroy PNGARG((png_structp png_ptr,
png_infop info_ptr, png_infop end_info_ptr));
/* Free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
PNG_EXTERN void png_write_destroy PNGARG((png_structp png_ptr));
#ifdef USE_FAR_KEYWORD /* memory model conversion function */
PNG_EXTERN void *png_far_to_near PNGARG((png_structp png_ptr, png_voidp ptr,
int check));
#endif /* USE_FAR_KEYWORD */
#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
PNG_EXTERN PNG_FUNCTION(void, png_fixed_error, (png_structp png_ptr,
png_const_charp name),PNG_NORETURN);
#endif
/* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
* the end. Always leaves the buffer nul terminated. Never errors out (and
* there is no error code.)
*/
PNG_EXTERN size_t png_safecat(png_charp buffer, size_t bufsize, size_t pos,
png_const_charp string);
/* Various internal functions to handle formatted warning messages, currently
* only implemented for warnings.
*/
#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
/* Utility to dump an unsigned value into a buffer, given a start pointer and
* and end pointer (which should point just *beyond* the end of the buffer!)
* Returns the pointer to the start of the formatted string. This utility only
* does unsigned values.
*/
PNG_EXTERN png_charp png_format_number(png_const_charp start, png_charp end,
int format, png_alloc_size_t number);
/* Convenience macro that takes an array: */
#define PNG_FORMAT_NUMBER(buffer,format,number) \
png_format_number(buffer, buffer + (sizeof buffer), format, number)
/* Suggested size for a number buffer (enough for 64 bits and a sign!) */
#define PNG_NUMBER_BUFFER_SIZE 24
/* These are the integer formats currently supported, the name is formed from
* the standard printf(3) format string.
*/
#define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
#define PNG_NUMBER_FORMAT_02u 2
#define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
#define PNG_NUMBER_FORMAT_02d 2
#define PNG_NUMBER_FORMAT_x 3
#define PNG_NUMBER_FORMAT_02x 4
#define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
#endif
#ifdef PNG_WARNINGS_SUPPORTED
/* New defines and members adding in libpng-1.5.4 */
# define PNG_WARNING_PARAMETER_SIZE 32
# define PNG_WARNING_PARAMETER_COUNT 8
/* An l-value of this type has to be passed to the APIs below to cache the
* values of the parameters to a formatted warning message.
*/
typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
PNG_WARNING_PARAMETER_SIZE];
PNG_EXTERN void png_warning_parameter(png_warning_parameters p, int number,
png_const_charp string);
/* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
* including the trailing '\0'.
*/
PNG_EXTERN void png_warning_parameter_unsigned(png_warning_parameters p,
int number, int format, png_alloc_size_t value);
/* Use png_alloc_size_t because it is an unsigned type as big as any we
* need to output. Use the following for a signed value.
*/
PNG_EXTERN void png_warning_parameter_signed(png_warning_parameters p,
int number, int format, png_int_32 value);
PNG_EXTERN void png_formatted_warning(png_structp png_ptr,
png_warning_parameters p, png_const_charp message);
/* 'message' follows the X/Open approach of using @1, @2 to insert
* parameters previously supplied using the above functions. Errors in
* specifying the paramters will simple result in garbage substitutions.
*/
#endif
/* ASCII to FP interfaces, currently only implemented if sCAL
* support is required.
*/
#ifdef PNG_sCAL_SUPPORTED
/* MAX_DIGITS is actually the maximum number of characters in an sCAL
* width or height, derived from the precision (number of significant
* digits - a build time settable option) and assumpitions about the
* maximum ridiculous exponent.
*/
#define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
#endif
#ifdef PNG_sCAL_SUPPORTED
#ifdef PNG_FLOATING_POINT_SUPPORTED
PNG_EXTERN void png_ascii_from_fp PNGARG((png_structp png_ptr, png_charp ascii,
png_size_t size, double fp, unsigned int precision));
#endif /* FLOATING_POINT */
#ifdef PNG_FIXED_POINT_SUPPORTED
PNG_EXTERN void png_ascii_from_fixed PNGARG((png_structp png_ptr,
png_charp ascii, png_size_t size, png_fixed_point fp));
#endif /* FIXED_POINT */
#endif /* READ_sCAL */
#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
/* An internal API to validate the format of a floating point number.
* The result is the index of the next character. If the number is
* not valid it will be the index of a character in the supposed number.
*
* The format of a number is defined in the PNG extensions specification
* and this API is strictly conformant to that spec, not anyone elses!
*
* The format as a regular expression is:
*
* [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
*
* or:
*
* [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
*
* The complexity is that either integer or fraction must be present and the
* fraction is permitted to have no digits only if the integer is present.
*
* NOTE: The dangling E problem.
* There is a PNG valid floating point number in the following:
*
* PNG floating point numb1.ers are not greedy.
*
* Working this out requires *TWO* character lookahead (because of the
* sign), the parser does not do this - it will fail at the 'r' - this
* doesn't matter for PNG sCAL chunk values, but it requires more care
* if the value were ever to be embedded in something more complex. Use
* ANSI-C strtod if you need the lookahead.
*/
/* State table for the parser. */
#define PNG_FP_INTEGER 0 /* before or in integer */
#define PNG_FP_FRACTION 1 /* before or in fraction */
#define PNG_FP_EXPONENT 2 /* before or in exponent */
#define PNG_FP_STATE 3 /* mask for the above */
#define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
#define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
#define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
#define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
#define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
/* These three values don't affect the parser. They are set but not used.
*/
#define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
#define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
#define PNG_FP_NONZERO 256 /* A non-zero value */
#define PNG_FP_STICKY 448 /* The above three flags */
/* This is available for the caller to store in 'state' if required. Do not
* call the parser after setting it (the parser sometimes clears it.)
*/
#define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
/* Result codes for the parser (boolean - true meants ok, false means
* not ok yet.)
*/
#define PNG_FP_MAYBE 0 /* The number may be valid in the future */
#define PNG_FP_OK 1 /* The number is valid */
/* Tests on the sticky non-zero and negative flags. To pass these checks
* the state must also indicate that the whole number is valid - this is
* achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
* is equivalent to PNG_FP_OK above.)
*/
#define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
/* NZ_MASK: the string is valid and a non-zero negative value */
#define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
/* Z MASK: the string is valid and a non-zero value. */
/* PNG_FP_SAW_DIGIT: the string is valid. */
#define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
/* The actual parser. This can be called repeatedly. It updates
* the index into the string and the state variable (which must
* be initialized to 0). It returns a result code, as above. There
* is no point calling the parser any more if it fails to advance to
* the end of the string - it is stuck on an invalid character (or
* terminated by '\0').
*
* Note that the pointer will consume an E or even an E+ and then leave
* a 'maybe' state even though a preceding integer.fraction is valid.
* The PNG_FP_WAS_VALID flag indicates that a preceding substring was
* a valid number. It's possible to recover from this by calling
* the parser again (from the start, with state 0) but with a string
* that omits the last character (i.e. set the size to the index of
* the problem character.) This has not been tested within libpng.
*/
PNG_EXTERN int png_check_fp_number PNGARG((png_const_charp string,
png_size_t size, int *statep, png_size_tp whereami));
/* This is the same but it checks a complete string and returns true
* only if it just contains a floating point number. As of 1.5.4 this
* function also returns the state at the end of parsing the number if
* it was valid (otherwise it returns 0.) This can be used for testing
* for negative or zero values using the sticky flag.
*/
PNG_EXTERN int png_check_fp_string PNGARG((png_const_charp string,
png_size_t size));
#endif /* pCAL || sCAL */
#if defined(PNG_READ_GAMMA_SUPPORTED) ||\
defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
/* Added at libpng version 1.5.0 */
/* This is a utility to provide a*times/div (rounded) and indicate
* if there is an overflow. The result is a boolean - false (0)
* for overflow, true (1) if no overflow, in which case *res
* holds the result.
*/
PNG_EXTERN int png_muldiv PNGARG((png_fixed_point_p res, png_fixed_point a,
png_int_32 multiplied_by, png_int_32 divided_by));
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
/* Same deal, but issue a warning on overflow and return 0. */
PNG_EXTERN png_fixed_point png_muldiv_warn PNGARG((png_structp png_ptr,
png_fixed_point a, png_int_32 multiplied_by, png_int_32 divided_by));
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED)
/* Calculate a reciprocal - used for gamma values. This returns
* 0 if the argument is 0 in order to maintain an undefined value,
* there are no warnings.
*/
PNG_EXTERN png_fixed_point png_reciprocal PNGARG((png_fixed_point a));
/* The same but gives a reciprocal of the product of two fixed point
* values. Accuracy is suitable for gamma calculations but this is
* not exact - use png_muldiv for that.
*/
PNG_EXTERN png_fixed_point png_reciprocal2 PNGARG((png_fixed_point a,
png_fixed_point b));
#endif
#ifdef PNG_READ_GAMMA_SUPPORTED
/* Internal fixed point gamma correction. These APIs are called as
* required to convert single values - they don't need to be fast,
* they are not used when processing image pixel values.
*
* While the input is an 'unsigned' value it must actually be the
* correct bit value - 0..255 or 0..65535 as required.
*/
PNG_EXTERN png_uint_16 png_gamma_correct PNGARG((png_structp png_ptr,
unsigned int value, png_fixed_point gamma_value));
PNG_EXTERN int png_gamma_significant PNGARG((png_fixed_point gamma_value));
PNG_EXTERN png_uint_16 png_gamma_16bit_correct PNGARG((unsigned int value,
png_fixed_point gamma_value));
PNG_EXTERN png_byte png_gamma_8bit_correct PNGARG((unsigned int value,
png_fixed_point gamma_value));
PNG_EXTERN void png_destroy_gamma_table(png_structp png_ptr);
PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr,
int bit_depth));
#endif
/* Missing declarations if FIXED_POINT is *not* supported - fixed properly
* in libpng 1.6
*/
#ifndef PNG_FIXED_POINT_SUPPORTED
#ifdef PNG_cHRM_SUPPORTED
PNG_EXTERN png_uint_32 png_get_cHRM_XYZ_fixed PNGARG(
(png_structp png_ptr, png_const_infop 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));
PNG_EXTERN void png_set_cHRM_XYZ_fixed PNGARG((png_structp png_ptr,
png_infop 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));
PNG_EXTERN 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
#ifdef PNG_gAMA_SUPPORTED
PNG_EXTERN png_uint_32 png_get_gAMA_fixed PNGARG(
(png_const_structp png_ptr, png_const_infop info_ptr,
png_fixed_point *int_file_gamma));
PNG_EXTERN void png_set_gAMA_fixed PNGARG((png_structp png_ptr,
png_infop info_ptr, png_fixed_point int_file_gamma));
#endif
#ifdef PNG_READ_BACKGROUND_SUPPORTED
PNG_EXTERN void png_set_background_fixed PNGARG((png_structp png_ptr,
png_const_color_16p background_color, int background_gamma_code,
int need_expand, png_fixed_point background_gamma));
#endif
#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
PNG_EXTERN void png_set_alpha_mode_fixed PNGARG((png_structp png_ptr,
int mode, png_fixed_point output_gamma));
#endif
#ifdef PNG_READ_GAMMA_SUPPORTED
PNG_EXTERN void png_set_gamma_fixed PNGARG((png_structp png_ptr,
png_fixed_point screen_gamma, png_fixed_point override_file_gamma));
#endif
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
PNG_EXTERN void png_set_rgb_to_gray_fixed PNGARG((png_structp png_ptr,
int error_action, png_fixed_point red, png_fixed_point green));
#endif
#endif /* FIX MISSING !FIXED_POINT DECLARATIONS */
/* These are initialization functions for hardware specific PNG filter
* optimizations; list these here then select the appropriate one at compile
* time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined
* the generic code is used.
*/
#ifdef PNG_FILTER_OPTIMIZATIONS
PNG_EXTERN void PNG_FILTER_OPTIMIZATIONS(png_structp png_ptr, unsigned int bpp);
/* Just declare the optimization that will be used */
#else
/* List *all* the possible optimizations here - this branch is required if
* the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
* CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
*/
PNG_EXTERN void png_init_filter_functions_neon(png_structp png_ptr,
unsigned int bpp);
#endif
/* Maintainer: Put new private prototypes here ^ */
#include "pngdebug.h"
#ifdef __cplusplus
}
#endif
#endif /* PNG_VERSION_INFO_ONLY */
#endif /* PNGPRIV_H */