kolibrios/programs/develop/libraries/libs-dev/libimg/png/libpng/png.inc
IgorA cdfe44d0b7 fix, optimize, clean code
git-svn-id: svn://kolibrios.org@6779 a494cfbc-eb01-0410-851d-a64ba20cac60
2016-12-02 16:13:46 +00:00

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; png.inc - header file for PNG reference library
; libpng version 1.6.25, September 1, 2016
; 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 1.6.25, September 1, 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.
; 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 1.6.25, September 1, 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
; Mandar Sahastrabuddhe
; 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
; Tim Wegner
; The PNG Reference Library is supplied "AS IS". The Contributing Authors
; and Group 42, Inc. disclaim all warranties, expressed or implied,
; including, without limitation, the warranties of merchantability and of
; fitness for any purpose. The Contributing Authors and Group 42, Inc.
; assume no liability for direct, indirect, incidental, special, exemplary,
; or consequential damages, which may result from the use of the PNG
; Reference Library, even if advised of the possibility of such damage.
; Permission is hereby granted to use, copy, modify, and distribute this
; source code, or portions hereof, for any purpose, without fee, subject
; to the following restrictions:
; 1. The origin of this source code must not be misrepresented.
; 2. Altered versions must be plainly marked as such and must not
; be misrepresented as being the original source.
; 3. This Copyright notice may not be removed or altered from any
; source or altered source distribution.
; The Contributing Authors and Group 42, Inc. specifically permit, without
; fee, and encourage the use of this source code as a component to
; supporting the PNG file format in commercial products. If you use this
; source code in a product, acknowledgment is not required but would be
; appreciated.
; 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).
; 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
; and occasional factors outside the authors' control, version numbering
; on the library has not always been consistent and straightforward.
; The following table summarizes matters since version 0.89c, which was
; the first widely used release:
;
; source png.h png.h shared-lib
; version string int version
; ------- ------ ----- ----------
; ...
; 1.2.56 13 10256 12.so.0.56[.0]
; ...
; 1.5.27 15 10527 15.so.15.27[.0]
; ...
; 1.6.25 16 10625 16.so.16.25[.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:
; =========================
; September 1, 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 1.6.25 are Y2K compliant. It is my belief that
; earlier versions were also Y2K compliant.
; Libpng only has two year fields. One is a 2-byte unsigned integer
; that will hold years up to 65535. The other, which is deprecated,
; holds the date in text format, and will hold years up to 9999.
; The integer is
; "uint_16 year" in png_time_struct.
; The string is
; "char time_buffer[29]" in png_struct. This is no longer used
; in libpng-1.6.x and will be removed from libpng-1.7.0.
; There are seven time-related functions:
; png.asm: png_convert_to_rfc_1123_buffer() in png.asm
; (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.asm, called in pngwrite.asm
; png_convert_from_time_t() in pngwrite.asm
; png_get_tIME() in pngget.asm
; png_handle_tIME() in pngrutil.asm, called in pngread.asm
; png_set_tIME() in pngset.asm
; png_write_tIME() in pngwutil.asm, called in pngwrite.asm
; All handle dates properly in a Y2K environment. The
; png_convert_from_time_t() function calls gmtime() to convert from system
; clock time, which returns (year - 1900), which we properly convert to
; the full 4-digit year. There is a possibility that libpng applications
; are not passing 4-digit years into the png_convert_to_rfc_1123_buffer()
; function, or that they are incorrectly passing only a 2-digit year
; instead of "year - 1900" into the png_convert_from_struct_tm() function,
; but this is not under our control. The libpng documentation has always
; stated that it works with 4-digit years, and the APIs have been
; documented as such.
; The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
; integer to hold the year, and can hold years as large as 65535.
; zlib, upon which libpng depends, is also Y2K compliant. It contains
; no date-related code.
; Glenn Randers-Pehrson
; libpng maintainer
; PNG Development Group
; This is not the place to learn how to use libpng. The file libpng-manual.txt
; describes how to use libpng, and the file example.c summarizes it
; with some code on which to build. This file is useful for looking
; at the actual function definitions and structure components. If 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.asm
PNG_LIBPNG_VER_STRING db '1.6.25',0
PNG_HEADER_VERSION_STRING db ' libpng version 1.6.25 - September 1, 2016',13,10,0
PNG_LIBPNG_VER_SONUM equ 16
PNG_LIBPNG_VER_DLLNUM equ 16
; These should match the first 3 components of PNG_LIBPNG_VER_STRING:
PNG_LIBPNG_VER_MAJOR equ 1
PNG_LIBPNG_VER_MINOR equ 6
PNG_LIBPNG_VER_RELEASE equ 25
; This should match the numeric part of the final component of
; PNG_LIBPNG_VER_STRING, omitting any leading zero:
PNG_LIBPNG_VER_BUILD equ 0
; Release Status
PNG_LIBPNG_BUILD_ALPHA equ 1
PNG_LIBPNG_BUILD_BETA equ 2
PNG_LIBPNG_BUILD_RC equ 3
PNG_LIBPNG_BUILD_STABLE equ 4
PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK equ 7
; Release-Specific Flags
PNG_LIBPNG_BUILD_PATCH equ 8 ;Can be OR'ed with PNG_LIBPNG_BUILD_STABLE only
PNG_LIBPNG_BUILD_PRIVATE equ 16 ;Cannot be OR'ed with PNG_LIBPNG_BUILD_SPECIAL
PNG_LIBPNG_BUILD_SPECIAL equ 32 ;Cannot be OR'ed with PNG_LIBPNG_BUILD_PRIVATE
PNG_LIBPNG_BUILD_BASE_TYPE equ 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
PNG_LIBPNG_VER equ 10625 ;1.6.25
; Library configuration: these options cannot be changed after
; the library has been built.
; 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.
;if PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
;# define PNG_LIBPNG_BUILD_TYPE \
; (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
;#else
;# ifdef PNG_LIBPNG_SPECIALBUILD
;# define PNG_LIBPNG_BUILD_TYPE \
; (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
;# else
;# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
;# endif
;end if
;#ifndef PNG_VERSION_INFO_ONLY
; Version information for C files, stored in png.asm. This had better match
; the version above.
;#define png_libpng_ver png_get_header_ver(NULL)
; 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.
; 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_25;
; 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.
; 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.
; 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'.
; 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 byte or uint_16 (as defined below).
struct png_color
red db ? ;byte
green db ? ;byte
blue db ? ;byte
ends
struct png_color_16
index db ? ;byte ;used for palette files
red dw ? ;uint_16 ;for use in red green blue files
green dw ? ;uint_16
blue dw ? ;uint_16
gray dw ? ;uint_16 ;for use in grayscale files
ends
struct png_color_8
red db ? ;byte ;for use in red green blue files
green db ? ;byte
blue db ? ;byte
gray db ? ;byte ;for use in grayscale files
alpha db ? ;byte ;for alpha channel files
ends
; The following two structures are used for the in-core representation
; of sPLT chunks.
struct png_sPLT_entry
red dw ? ;uint_16
green dw ? ;uint_16
blue dw ? ;uint_16
alpha dw ? ;uint_16
frequency dw ? ;uint_16
ends
; 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.
struct png_sPLT_t
name dd ? ;charp ;palette name
depth db ? ;byte ;depth of palette samples
entries dd ? ;png_sPLT_entryp ;palette entries
nentries dd ? ;int_32 ;number of palette entries
ends
if PNG_TEXT_SUPPORTED eq 1
; png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
; and whether that contents is compressed or not. The "key" field
; points to a regular zero-terminated C string. The "text" fields can be a
; regular C string, an empty string, or a NULL pointer.
; However, the structure returned by png_get_text() will always contain
; the "text" field as a regular zero-terminated C string (possibly
; empty), never a NULL pointer, so it can be safely used in printf() and
; other string-handling functions. Note that the "itxt_length", "lang", and
; "lang_key" members of the structure only exist when the library is built
; with iTXt chunk support. Prior to libpng-1.4.0 the library was built by
; default without iTXt support. Also note that when iTXt *is* supported,
; the "lang" and "lang_key" fields contain NULL pointers when the
; "compression" field contains * PNG_TEXT_COMPRESSION_NONE or
; PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the
; same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"
; which is always 0 or 1, or its "compression method" which is always 0.
struct png_text
compression dd ? ;int ;compression value:
;-1: tEXt, none
; 0: zTXt, deflate
; 1: iTXt, none
; 2: iTXt, deflate
key dd ? ;charp ;keyword, 1-79 character description of "text"
text dd ? ;charp ;comment, may be an empty string (ie "")
; or a NULL pointer
text_length dd ? ;png_size_t ;length of the text string
itxt_length dd ? ;png_size_t ;length of the itxt string
lang dd ? ;charp ;language code, 0-79 characters
; or a NULL pointer
lang_key dd ? ;charp ;keyword translated UTF-8 string, 0 or more
; chars or a NULL pointer
ends
end if
; Supported compression types for text in PNG files (tEXt, and zTXt).
; The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed.
PNG_TEXT_COMPRESSION_NONE_WR equ -3
PNG_TEXT_COMPRESSION_zTXt_WR equ -2
PNG_TEXT_COMPRESSION_NONE equ -1
PNG_TEXT_COMPRESSION_zTXt equ 0
PNG_ITXT_COMPRESSION_NONE equ 1
PNG_ITXT_COMPRESSION_zTXt equ 2
PNG_TEXT_COMPRESSION_LAST equ 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!
struct png_time
year dw ? ;uint_16 ;full year, as in, 1995
month db ? ;byte ;month of year, 1 - 12
day db ? ;byte ;day of month, 1 - 31
hour db ? ;byte ;hour of day, 0 - 23
minute db ? ;byte ;minute of hour, 0 - 59
second db ? ;byte ;second of minute, 0 - 60 (for leap seconds)
ends
if (PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED eq 1) | (PNG_USER_CHUNKS_SUPPORTED eq 1)
; 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.
struct png_unknown_chunk
name rb 5 ;byte[5] ;Textual chunk name with '\0' terminator
podata dd ? ;byte* ;Data, should not be modified on read!
size dd ? ;png_size_t
; 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.
location db ? ;byte ;mode of operation at read time
ends
end if
; Flag values for the unknown chunk location byte.
PNG_HAVE_IHDR equ 0x01
PNG_HAVE_PLTE equ 0x02
PNG_AFTER_IDAT equ 0x08
; Maximum positive integer used in PNG is (2^31)-1
PNG_UINT_31_MAX equ 0x7fffffff ;uint_32
PNG_UINT_32_MAX equ -1 ;uint_32
PNG_SIZE_MAX equ 0x60000000 ;1.5 Gb
; These are constants for fixed point values encoded in the
; PNG specification manner (x100000)
PNG_FP_1 equ 100000
PNG_FP_HALF equ 50000
PNG_FP_MAX equ ((png_fixed_point)0x7fffffffL)
PNG_FP_MIN equ (-PNG_FP_MAX)
; These describe the color_type field in png_info.
; color type masks
PNG_COLOR_MASK_PALETTE equ 1
PNG_COLOR_MASK_COLOR equ 2
PNG_COLOR_MASK_ALPHA equ 4
; color types. Note that not all combinations are legal
PNG_COLOR_TYPE_GRAY equ 0
PNG_COLOR_TYPE_PALETTE equ (PNG_COLOR_MASK_COLOR or PNG_COLOR_MASK_PALETTE)
PNG_COLOR_TYPE_RGB equ (PNG_COLOR_MASK_COLOR)
PNG_COLOR_TYPE_RGB_ALPHA equ (PNG_COLOR_MASK_COLOR or PNG_COLOR_MASK_ALPHA)
PNG_COLOR_TYPE_GRAY_ALPHA equ (PNG_COLOR_MASK_ALPHA)
; aliases
PNG_COLOR_TYPE_RGBA equ PNG_COLOR_TYPE_RGB_ALPHA
PNG_COLOR_TYPE_GA equ PNG_COLOR_TYPE_GRAY_ALPHA
; This is for compression type. PNG 1.0-1.2 only define the single type.
PNG_COMPRESSION_TYPE_BASE equ 0 ;Deflate method 8, 32K window
PNG_COMPRESSION_TYPE_DEFAULT equ PNG_COMPRESSION_TYPE_BASE
; This is for filter type. PNG 1.0-1.2 only define the single type.
PNG_FILTER_TYPE_BASE equ 0 ;Single row per-byte filtering
PNG_INTRAPIXEL_DIFFERENCING equ 64 ;Used only in MNG datastreams
PNG_FILTER_TYPE_DEFAULT equ PNG_FILTER_TYPE_BASE
; These are for the interlacing type. These values should NOT be changed.
PNG_INTERLACE_NONE equ 0 ;Non-interlaced image
PNG_INTERLACE_ADAM7 equ 1 ;Adam7 interlacing
PNG_INTERLACE_LAST equ 2 ;Not a valid value
; These are for the oFFs chunk. These values should NOT be changed.
PNG_OFFSET_PIXEL equ 0 ;Offset in pixels
PNG_OFFSET_MICROMETER equ 1 ;Offset in micrometers (1/10^6 meter)
PNG_OFFSET_LAST equ 2 ;Not a valid value
; These are for the pCAL chunk. These values should NOT be changed.
PNG_EQUATION_LINEAR equ 0 ;Linear transformation
PNG_EQUATION_BASE_E equ 1 ;Exponential base e transform
PNG_EQUATION_ARBITRARY equ 2 ;Arbitrary base exponential transform
PNG_EQUATION_HYPERBOLIC equ 3 ;Hyperbolic sine transformation
PNG_EQUATION_LAST equ 4 ;Not a valid value
; These are for the sCAL chunk. These values should NOT be changed.
PNG_SCALE_UNKNOWN equ 0 ;unknown unit (image scale)
PNG_SCALE_METER equ 1 ;meters per pixel
PNG_SCALE_RADIAN equ 2 ;radians per pixel
PNG_SCALE_LAST equ 3 ;Not a valid value
; These are for the pHYs chunk. These values should NOT be changed.
PNG_RESOLUTION_UNKNOWN equ 0 ;pixels/unknown unit (aspect ratio)
PNG_RESOLUTION_METER equ 1 ;pixels/meter
PNG_RESOLUTION_LAST equ 2 ;Not a valid value
; These are for the sRGB chunk. These values should NOT be changed.
PNG_sRGB_INTENT_PERCEPTUAL equ 0
PNG_sRGB_INTENT_RELATIVE equ 1
PNG_sRGB_INTENT_SATURATION equ 2
PNG_sRGB_INTENT_ABSOLUTE equ 3
PNG_sRGB_INTENT_LAST equ 4 ;Not a valid value
; This is for text chunks
PNG_KEYWORD_MAX_LENGTH equ 79
; Maximum number of entries in PLTE/sPLT/tRNS arrays
PNG_MAX_PALETTE_LENGTH equ 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.
PNG_INFO_gAMA equ 0x0001
PNG_INFO_sBIT equ 0x0002
PNG_INFO_cHRM equ 0x0004
PNG_INFO_PLTE equ 0x0008
PNG_INFO_tRNS equ 0x0010
PNG_INFO_bKGD equ 0x0020
PNG_INFO_hIST equ 0x0040
PNG_INFO_pHYs equ 0x0080
PNG_INFO_oFFs equ 0x0100
PNG_INFO_tIME equ 0x0200
PNG_INFO_pCAL equ 0x0400
PNG_INFO_sRGB equ 0x0800 ; GR-P, 0.96a
PNG_INFO_iCCP equ 0x1000 ; ESR, 1.0.6
PNG_INFO_sPLT equ 0x2000 ; ESR, 1.0.6
PNG_INFO_sCAL equ 0x4000 ; ESR, 1.0.6
PNG_INFO_IDAT equ 0x8000 ; ESR, 1.0.6
; This is used for the transformation routines, as some of them
; change these values for the row. It also should enable using
; the routines for other purposes.
struct png_row_info ;png_row_info_struct
width dd ? ;uint_32 ;width of row
rowbytes dd ? ;png_size_t ;number of bytes in row
color_type db ? ;byte ;color type of row
bit_depth db ? ;byte ;bit depth of row
channels db ? ;byte ;number of channels (1, 2, 3, or 4)
pixel_depth db ? ;byte ;bits per pixel (depth * channels)
ends
if PNG_SETJMP_SUPPORTED eq 1
; 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);
end if
; Transform masks for the high-level interface
PNG_TRANSFORM_IDENTITY equ 0x0000 ; read and write
PNG_TRANSFORM_STRIP_16 equ 0x0001 ; read only
PNG_TRANSFORM_STRIP_ALPHA equ 0x0002 ; read only
PNG_TRANSFORM_PACKING equ 0x0004 ; read and write
PNG_TRANSFORM_PACKSWAP equ 0x0008 ; read and write
PNG_TRANSFORM_EXPAND equ 0x0010 ; read only
PNG_TRANSFORM_INVERT_MONO equ 0x0020 ; read and write
PNG_TRANSFORM_SHIFT equ 0x0040 ; read and write
PNG_TRANSFORM_BGR equ 0x0080 ; read and write
PNG_TRANSFORM_SWAP_ALPHA equ 0x0100 ; read and write
PNG_TRANSFORM_SWAP_ENDIAN equ 0x0200 ; read and write
PNG_TRANSFORM_INVERT_ALPHA equ 0x0400 ; read and write
PNG_TRANSFORM_STRIP_FILLER equ 0x0800 ; write only
; Added to libpng-1.2.34
PNG_TRANSFORM_STRIP_FILLER_BEFORE equ PNG_TRANSFORM_STRIP_FILLER
PNG_TRANSFORM_STRIP_FILLER_AFTER equ 0x1000 ; write only
; Added to libpng-1.4.0
PNG_TRANSFORM_GRAY_TO_RGB equ 0x2000 ; read only
; Added to libpng-1.5.4
PNG_TRANSFORM_EXPAND_16 equ 0x4000 ;read only
;if INT_MAX >= 0x8000 ;else this might break
PNG_TRANSFORM_SCALE_16 equ 0x8000 ;read only
;end if
; Flags for MNG supported features
PNG_FLAG_MNG_EMPTY_PLTE equ 0x01
PNG_FLAG_MNG_FILTER_64 equ 0x04
PNG_ALL_MNG_FEATURES equ 0x05
; NOTE: prior to 1.5 these functions had no 'API' style declaration,
; this allowed the zlib default functions to be used on Windows
; platforms. In 1.5 the zlib default malloc (which just calls malloc and
; ignores the first argument) should be completely compatible with the
; following.
; 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
macro PNG_EXPORT ordinal, typ, nam, arg
{
align 4
nam:
local .end_t
local .m_txt
jmp .end_t
.m_txt db `nam,13,10,0
.end_t:
stdcall dbg_print,txt_zv,.m_txt
ret
}
; Simple signature checking function. This is the same as calling
; png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
;#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n))
macro png_setup_abs sum
{
local .end0
and eax,0xff
if PNG_USE_ABS eq 1
add sum,128
sub al,128 ;v - 128
cmp al,128
jl @f
neg al
inc al ;abs(v - 128)
@@:
sub sum,eax
else
cmp eax,128
jl @f
add sum,256
sub sum,eax
jmp .end0
@@:
add sum,eax
.end0:
end if
}
; Reduce RGB to grayscale.
PNG_ERROR_ACTION_NONE equ 1
PNG_ERROR_ACTION_WARN equ 2
PNG_ERROR_ACTION_ERROR equ 3
PNG_RGB_TO_GRAY_DEFAULT equ (-1) ;for red/green coefficients
; 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:
PNG_ALPHA_PNG equ 0 ;according to the PNG standard
PNG_ALPHA_STANDARD equ 1 ;according to Porter/Duff
PNG_ALPHA_ASSOCIATED equ 1 ;as above; this is the normal practice
PNG_ALPHA_PREMULTIPLIED equ 1 ;as above
PNG_ALPHA_OPTIMIZED equ 2 ;'PNG' for opaque pixels, else 'STANDARD'
PNG_ALPHA_BROKEN equ 3 ;the alpha channel is gamma encoded
if (PNG_GAMMA_SUPPORTED eq 1) | (PNG_READ_ALPHA_MODE_SUPPORTED eq 1)
; The output_gamma value is a screen gamma in libpng terminology: it expresses
; how to decode the output values, not how they are encoded.
PNG_DEFAULT_sRGB equ -1 ;sRGB gamma and color space
PNG_GAMMA_MAC_18 equ -2 ;Old Mac '1.8' gamma and color space
PNG_GAMMA_sRGB equ 220000 ;Television standards--matches sRGB gamma
PNG_GAMMA_LINEAR equ PNG_FP_1 ;Linear
end if
; The values of the PNG_FILLER_ defines should NOT be changed
PNG_FILLER_BEFORE equ 0
PNG_FILLER_AFTER equ 1
;#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_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.
if PNG_READ_BACKGROUND_SUPPORTED eq 1
PNG_BACKGROUND_GAMMA_UNKNOWN equ 0
PNG_BACKGROUND_GAMMA_SCREEN equ 1
PNG_BACKGROUND_GAMMA_FILE equ 2
PNG_BACKGROUND_GAMMA_UNIQUE equ 3
end if
;PNG_READ_16_TO_8_SUPPORTED equ 1 ;Name prior to 1.5.4
; The threshold on gamma processing is configurable but hard-wired into the
; library. The following is the floating point variant.
PNG_GAMMA_THRESHOLD equ (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!
; 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
PNG_CRC_DEFAULT equ 0 ;error/quit warn/discard data
PNG_CRC_ERROR_QUIT equ 1 ;error/quit error/quit
PNG_CRC_WARN_DISCARD equ 2 ;(INVALID) warn/discard data
PNG_CRC_WARN_USE equ 3 ;warn/use data warn/use data
PNG_CRC_QUIET_USE equ 4 ;quiet/use data quiet/use data
PNG_CRC_NO_CHANGE equ 5 ;use current value use current value
; 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.
PNG_NO_FILTERS equ 0x00
PNG_FILTER_NONE equ 0x08
PNG_FILTER_SUB equ 0x10
PNG_FILTER_UP equ 0x20
PNG_FILTER_AVG equ 0x40
PNG_FILTER_PAETH equ 0x80
PNG_FAST_FILTERS equ (PNG_FILTER_NONE or PNG_FILTER_SUB or PNG_FILTER_UP)
PNG_ALL_FILTERS equ (PNG_FAST_FILTERS or PNG_FILTER_AVG or PNG_FILTER_PAETH)
; Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
; These defines should NOT be changed.
PNG_FILTER_VALUE_NONE equ 0
PNG_FILTER_VALUE_SUB equ 1
PNG_FILTER_VALUE_UP equ 2
PNG_FILTER_VALUE_AVG equ 3
PNG_FILTER_VALUE_PAETH equ 4
PNG_FILTER_VALUE_LAST equ 5
; The following are no longer used and will be removed from libpng-1.7:
PNG_FILTER_HEURISTIC_DEFAULT equ 0 ;Currently "UNWEIGHTED"
PNG_FILTER_HEURISTIC_UNWEIGHTED equ 1 ;Used by libpng < 0.95
PNG_FILTER_HEURISTIC_WEIGHTED equ 2 ;Experimental feature
PNG_FILTER_HEURISTIC_LAST equ 3 ;Not a valid value
; 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-manual.txt for
; more information.
; Replace the default data input function with a user supplied one.
PNG_EXPORT 78, void, png_set_read_fn, '(png_structrp png_ptr, voidp io_ptr, png_rw_ptr read_data_fn)'
; Reassign responsibility for freeing existing data, whether allocated
; by libpng or by the application; this works on the png_info structure passed
; in, it does not change the state for other png_info structures.
; It is unlikely that this function works correctly as of 1.6.0 and using it
; may result either in memory leaks or double free of allocated data.
; Assignments for png_data_freer
PNG_DESTROY_WILL_FREE_DATA equ 1
PNG_SET_WILL_FREE_DATA equ 1
PNG_USER_WILL_FREE_DATA equ 2
; Flags for png_ptr->free_me and info_ptr->free_me
PNG_FREE_HIST equ 0x0008
PNG_FREE_ICCP equ 0x0010
PNG_FREE_SPLT equ 0x0020
PNG_FREE_ROWS equ 0x0040
PNG_FREE_PCAL equ 0x0080
PNG_FREE_SCAL equ 0x0100
if PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED eq 1
PNG_FREE_UNKN equ 0x0200
end if
PNG_FREE_LIST equ 0x0400 ;removed in 1.6.0 because it is ignored
PNG_FREE_PLTE equ 0x1000
PNG_FREE_TRNS equ 0x2000
PNG_FREE_TEXT equ 0x4000
PNG_FREE_ALL equ 0x7fff
PNG_FREE_MUL equ 0x4220 ;PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN
;if PNG_ERROR_TEXT_SUPPORTED
; The same, but the chunk name is prepended to the error string.
;PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr,
; charp error_message), PNG_NORETURN);
;#else
; Fatal error in PNG image of libpng - can't continue
;PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN);
;# define png_chunk_error(s1,s2) png_err(s1)
;end if
; Non-fatal error in libpng, chunk name is prepended to message.
PNG_EXPORT 106, void, png_chunk_warning, '(png_const_structrp png_ptr, charp warning_message)'
;#else
;# define png_warning(s1,s2) ((void)(s1))
;# define png_chunk_warning(s1,s2) ((void)(s1))
; 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, charp warning_message)'
;if PNG_READ_SUPPORTED
; Same, chunk name is prepended to message (only during read)
PNG_EXPORT 108, void, png_chunk_benign_error, '(png_const_structrp png_ptr, charp warning_message)'
;#else
;# ifdef PNG_ALLOW_BENIGN_ERRORS
macro png_benign_error h,txt
{
png_warning h,txt
}
;# define png_chunk_benign_error png_chunk_warning
;# else
;# define png_benign_error png_error
;# define png_chunk_benign_error png_chunk_error
;# endif
;end if
; 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.
; For use in png_set_keep_unknown, added to version 1.2.6
PNG_HANDLE_CHUNK_AS_DEFAULT equ 0
PNG_HANDLE_CHUNK_NEVER equ 1
PNG_HANDLE_CHUNK_IF_SAFE equ 2
PNG_HANDLE_CHUNK_ALWAYS equ 3
PNG_HANDLE_CHUNK_LAST equ 4
; Removed from libpng 1.6; use png_get_io_chunk_type.
;PNG_REMOVED(200, bytep, png_get_io_chunk_name, (png_structrp png_ptr),
; PNG_DEPRECATED)
; The flags returned by png_get_io_state() are the following:
PNG_IO_NONE equ 0x0000 ; no I/O at this moment
PNG_IO_READING equ 0x0001 ; currently reading
PNG_IO_WRITING equ 0x0002 ; currently writing
PNG_IO_SIGNATURE equ 0x0010 ; currently at the file signature
PNG_IO_CHUNK_HDR equ 0x0020 ; currently at the chunk header
PNG_IO_CHUNK_DATA equ 0x0040 ; currently at the chunk data
PNG_IO_CHUNK_CRC equ 0x0080 ; currently at the chunk crc
PNG_IO_MASK_OP equ 0x000f ; current operation: reading/writing
PNG_IO_MASK_LOC equ 0x00f0 ; current location: sig/hdr/data/crc
;end if /* 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.
PNG_INTERLACE_ADAM7_PASSES equ 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.
macro PNG_PASS_START_ROW pass
{
push ebx ecx
mov eax,pass
mov ebx,eax
not eax
and eax,1
shr ebx,1
mov ecx,3
sub ecx,ebx
shl eax,cl
and eax,7
pop ecx ebx
}
macro PNG_PASS_START_COL pass
{
push ebx ecx
mov eax,pass
mov ebx,eax
and eax,1
inc ebx
shr ebx,1
mov ecx,3
sub ecx,ebx
shl eax,cl
and eax,7
pop ecx ebx
}
; 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.
macro PNG_PASS_ROW_SHIFT pass
{
local .end0
mov eax,3
cmp pass,2
jle .end0
mov eax,8
sub eax,pass
shr eax,1
.end0:
}
macro PNG_PASS_COL_SHIFT pass
{
local .end0
mov eax,3
cmp pass,1
jle .end0
mov eax,7
sub eax,pass
shr eax,1
.end0:
}
; 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.
macro PNG_PASS_ROWS height, pass
{
push ecx
push ebx
PNG_PASS_START_ROW pass
mov ebx,eax
PNG_PASS_ROW_SHIFT pass
mov ecx,eax
xor eax,eax
inc eax
shl eax,cl
dec eax
sub eax,ebx
pop ebx
add eax,height
shr eax,cl
pop ecx
}
macro PNG_PASS_COLS width, pass
{
push ecx
push ebx
PNG_PASS_START_COL pass
mov ebx,eax
PNG_PASS_COL_SHIFT pass
mov ecx,eax
xor eax,eax
inc eax
shl eax,cl
dec eax
sub eax,ebx
pop ebx
add eax,width
shr eax,cl
pop ecx
}
; 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)
;if 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) \
; { \
; uint_16 temp = (uint_16)((uint_16)(fg) \
; * (uint_16)(alpha) \
; + (uint_16)(bg)*(uint_16)(255 \
; - (uint_16)(alpha)) + 128); \
; (composite) = (byte)(((temp + (temp >> 8)) >> 8) & 0xff); \
; }
;# define png_composite_16(composite, fg, alpha, bg) \
; { \
; uint_32 temp = (uint_32)((uint_32)(fg) \
; * (uint_32)(alpha) \
; + (uint_32)(bg)*(65535 \
; - (uint_32)(alpha)) + 32768); \
; (composite) = (uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); \
; }
;#else /* Standard method using integer division */
;# define png_composite(composite, fg, alpha, bg) \
; (composite) = \
; (byte)(0xff & (((uint_16)(fg) * (uint_16)(alpha) + \
; (uint_16)(bg) * (uint_16)(255 - (uint_16)(alpha)) + \
; 127) / 255))
;# define png_composite_16(composite, fg, alpha, bg) \
; (composite) = \
; (uint_16)(0xffff & (((uint_32)(fg) * (uint_32)(alpha) + \
; (uint_32)(bg)*(uint_32)(65535 - (uint_32)(alpha)) + \
; 32767) / 65535))
;end if /* READ_COMPOSITE_NODIV */
if PNG_USE_READ_MACROS eq 1
; 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) \
; (((uint_32)(*(buf)) << 24) + \
; ((uint_32)(*((buf) + 1)) << 16) + \
; ((uint_32)(*((buf) + 2)) << 8) + \
; ((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 uint_32.
;# define PNG_get_uint_16(buf) \
; ((uint_16) \
; (((unsigned int)(*(buf)) << 8) + \
; ((unsigned int)(*((buf) + 1)))))
;# define PNG_get_int_32(buf) \
; ((int_32)((*(buf) & 0x80) \
; ? -((int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \
; : (int_32)png_get_uint_32(buf)))
end if
;/*******************************************************************************
; 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)
PNG_IMAGE_VERSION equ 1
struct png_image
opaque dd ? ;png_controlp ;Initialize to NULL, free with png_image_free
version dd ? ;uint_32 ;Set to PNG_IMAGE_VERSION
width dd ? ;uint_32 ;Image width in pixels (columns)
height dd ? ;uint_32 ;Image height in pixels (rows)
format dd ? ;uint_32 ;Image format as defined below
flags dd ? ;uint_32 ;A bit mask containing informational flags
colormap_entries dd ? ;uint_32 ;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:
PNG_IMAGE_WARNING equ 1
PNG_IMAGE_ERROR equ 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)
warning_or_error dd ? ;uint_32
message rb 64 ;char[64]
ends
; 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
PNG_FORMAT_FLAG_ALPHA equ 0x01 ;format with an alpha channel
PNG_FORMAT_FLAG_COLOR equ 0x02 ;color format: otherwise grayscale
PNG_FORMAT_FLAG_LINEAR equ 0x04 ;2-byte channels else 1-byte
PNG_FORMAT_FLAG_COLORMAP equ 0x08 ;image data is color-mapped
PNG_FORMAT_FLAG_BGR equ 0x10 ;BGR colors, else order is RGB
PNG_FORMAT_FLAG_AFIRST equ 0x20 ;alpha channel comes first
; Commonly used formats have predefined macros.
; First the single byte (sRGB) formats:
PNG_FORMAT_GRAY equ 0
PNG_FORMAT_GA equ PNG_FORMAT_FLAG_ALPHA
PNG_FORMAT_AG equ (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST)
PNG_FORMAT_RGB equ PNG_FORMAT_FLAG_COLOR
PNG_FORMAT_BGR equ (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR)
PNG_FORMAT_RGBA equ (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA)
PNG_FORMAT_ARGB equ (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST)
PNG_FORMAT_BGRA equ (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA)
PNG_FORMAT_ABGR equ (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.
PNG_FORMAT_LINEAR_Y equ PNG_FORMAT_FLAG_LINEAR
PNG_FORMAT_LINEAR_Y_ALPHA equ (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA)
PNG_FORMAT_LINEAR_RGB equ (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR)
PNG_FORMAT_LINEAR_RGB_ALPHA equ\
(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.
PNG_FORMAT_RGB_COLORMAP equ (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP)
PNG_FORMAT_BGR_COLORMAP equ (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP)
PNG_FORMAT_RGBA_COLORMAP equ (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP)
PNG_FORMAT_ARGB_COLORMAP equ (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP)
PNG_FORMAT_BGRA_COLORMAP equ (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP)
PNG_FORMAT_ABGR_COLORMAP equ (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.
macro PNG_IMAGE_SAMPLE_CHANNELS fmt
{
mov eax,fmt
and eax,PNG_FORMAT_FLAG_COLOR or PNG_FORMAT_FLAG_ALPHA
inc eax
}
; 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:
; uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)];
; 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
macro PNG_IMAGE_PIXEL_ p1,fmt
{
local .end0
local .end1
mov eax,fmt
and eax,PNG_FORMAT_FLAG_COLORMAP
cmp eax,0
je .end0
xor eax,eax
inc eax
jmp .end1
.end0:
p1 fmt
.end1:
}
macro 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.
PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB equ 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.
PNG_IMAGE_FLAG_FAST equ 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.
PNG_IMAGE_FLAG_16BIT_sRGB equ 0x04
; On read if the image is a 16-bit per component image and there is no gAMA
; or sRGB chunk assume that the components are sRGB encoded. Notice that
; images output by the simplified API always have gamma information; setting
; this flag only affects the interpretation of 16-bit images from an
; external source. It is recommended that the application expose this flag
; to the user; the user can normally easily recognize the difference between
; linear and sRGB encoding. This flag has no effect on write - the data
; passed to the write APIs must have the correct encoding (as defined
; above.)
; If the flag is not set (the default) input 16-bit per component data is
; assumed to be linear.
; NOTE: the flag can only be set after the png_image_begin_read_ call,
; because that call initializes the 'flags' field.
if PNG_SIMPLIFIED_WRITE_SUPPORTED eq 1
; 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)
; 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.
;#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.
;end if
;#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.
end if ;SIMPLIFIED_WRITE
;/*******************************************************************************
; END OF SIMPLIFIED API
; ******************************************************************************/
;end if /* 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.
if PNG_SET_OPTION_SUPPORTED eq 1
if PNG_ARM_NEON_API_SUPPORTED eq 1
PNG_ARM_NEON equ 0 ;HARDWARE: ARM Neon SIMD instructions supported
end if
PNG_MAXIMUM_INFLATE_WINDOW equ 2 ;SOFTWARE: force maximum window
PNG_SKIP_sRGB_CHECK_PROFILE equ 4 ;SOFTWARE: Check ICC profile for sRGB
if PNG_MIPS_MSA_API_SUPPORTED eq 1
PNG_MIPS_MSA equ 6 ;HARDWARE: MIPS Msa SIMD instructions supported
end if
PNG_OPTION_NEXT equ 8 ;Next option - numbers must be even
; Return values: NOTE: there are four values and 'off' is *not* zero
PNG_OPTION_UNSET equ 0 ;Unset - defaults to off
PNG_OPTION_INVALID equ 1 ;Option number out of range
PNG_OPTION_OFF equ 2
PNG_OPTION_ON equ 3
end if ;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.)
;end if /* PNG_VERSION_INFO_ONLY */
; Do not put anything past this line