/* png.h - header file for PNG reference library
*
* libpng version 1.0.3 - January 14, 1999
* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
* Copyright (c) 1996, 1997 Andreas Dilger
* Copyright (c) 1998, 1999 Glenn Randers-Pehrson
*
* Y2K compliance in libpng:
* =========================
*
* January 13, 1999
*
* 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 0.81 and
* upward are Y2K compliant. It is my belief that earlier versions were
* also Y2K compliant.
*
* Libpng only has three year fields. One is a 2-byte unsigned integer
* that will hold years up to 65535. The other two hold the date in text
* format, and will hold years up to 9999.
*
* The integer is
* "png_uint_16 year" in png_time_struct.
*
* The strings are
* "png_charp time_buffer" in png_struct and
* "near_time_buffer", which is a local character string in png.c.
*
* There are seven time-related functions:
* png.c: png_convert_to_rfc_1123() in png.c
* (formerly png_convert_to_rfc_1152() in error)
* png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
* png_convert_from_time_t() in pngwrite.c
* png_get_tIME() in pngget.c
* png_handle_tIME() in pngrutil.c, called in pngread.c
* png_set_tIME() in pngset.c
* png_write_tIME() in pngwutil.c, called in pngwrite.c
*
* All handle dates properly in a Y2K environment. The
* png_convert_from_time_t() function calls gmtime() to convert from system
* clock time, which returns (year - 1900), which we properly convert to
* the full 4-digit year. There is a possibility that applications using
* libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
* function, or 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.
*
*
* Glenn Randers-Pehrson
* libpng maintainer
* PNG Development Group
*
* Note about libpng version numbers:
*
* Due to various miscommunications, unforeseen code incompatibilities
* and occasional factors outside the authors' control, version numbering
* on the library has not always been consistent and straightforward.
* The following table summarizes matters since version 0.89c, which was
* the first widely used release:
*
* source png.h png.h shared-lib
* version string int version
* ------- ------ ----- ----------
* 0.89c ("1.0 beta 3") 0.89 89 1.0.89
* 0.90 ("1.0 beta 4") 0.90 90 0.90 [should have been 2.0.90]
* 0.95 ("1.0 beta 5") 0.95 95 0.95 [should have been 2.0.95]
* 0.96 ("1.0 beta 6") 0.96 96 0.96 [should have been 2.0.96]
* 0.97b ("1.00.97 beta 7") 1.00.97 97 1.0.1 [should have been 2.0.97]
* 0.97c 0.97 97 2.0.97
* 0.98 0.98 98 2.0.98
* 0.99 0.99 98 2.0.99
* 0.99a-m 0.99 99 2.0.99
* 1.00 1.00 100 2.1.0 [int should be 10000]
* 1.0.0 1.0.0 100 2.1.0 [int should be 10000]
* 1.0.1 1.0.1 10001 2.1.0
* 1.0.1a-e 1.0.1a-e 10002 2.1.0.1a-e
* 1.0.2 1.0.2 10002 2.1.0.2
* 1.0.2a-c 1.0.2a 10003 2.1.0.2a-c
* 1.0.3 1.0.3 10003 2.1.0.3
*
* Henceforth the source version will match the shared-library minor
* and patch numbers; the shared-library major version number will be
* used for changes in backward compatibility, as it is intended. The
* PNG_PNGLIB_VER macro, which is not used within libpng but is available
* for applications, is an unsigned integer of the form xyyzz corresponding
* to the source version x.y.z (leading zeros in y and z).
*
* See libpng.txt or libpng.3 for more information. The PNG specification
* is available as RFC 2083
* and as a W3C Recommendation
*
* Contributing Authors:
* John Bowler
* Kevin Bracey
* Sam Bushell
* Andreas Dilger
* Magnus Holmgren
* Tom Lane
* Dave Martindale
* Glenn Randers-Pehrson
* Greg Roelofs
* Guy Eric Schalnat
* Paul Schmidt
* Tom Tanner
* Willem van Schaik
* Tim Wegner
*
* The contributing authors would like to thank all those who helped
* with testing, bug fixes, and patience. This wouldn't have been
* possible without all of you.
*
* Thanks to Frank J. T. Wojcik for helping with the documentation.
*
* COPYRIGHT NOTICE:
*
* 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.
*/
#ifndef _PNG_H
#define _PNG_H
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/* This is not the place to learn how to use libpng. The file libpng.txt
* describes how to use libpng, and the file example.c summarizes it
* with some code on which to build. This file is useful for looking
* at the actual function definitions and structure components.
*/
/* include the compression library's header */
#include "zlib.h"
/* include all user configurable info */
#include "pngconf.h"
/* This file is arranged in several sections. The first section contains
* structure and type definitions. The second section contains the external
* library functions, while the third has the internal library functions,
* which applications aren't expected to use directly.
*/
/* Version information for png.h - this should match the version in png.c */
#define PNG_LIBPNG_VER_STRING "1.0.3"
/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
* We must not include leading zeros.
* Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
* version 1.0.0 was mis-numbered 100 instead of 10000). From
* version 1.0.1 it's xxyyzz, where x=major, y=minor, z=bugfix */
#define PNG_LIBPNG_VER 10003 /* 1.0.3 */
/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
/* Version information for C files, stored in png.c. This had better match
* the version above.
*/
extern char png_libpng_ver[12]; /* need room for 99.99.99aa */
/* Structures to facilitate easy interlacing. See png.c for more details */
extern int FARDATA png_pass_start[7];
extern int FARDATA png_pass_inc[7];
extern int FARDATA png_pass_ystart[7];
extern int FARDATA png_pass_yinc[7];
extern int FARDATA png_pass_mask[7];
extern int FARDATA png_pass_dsp_mask[7];
/* These aren't currently used. If you need them, see png.c for more details
extern int FARDATA png_pass_width[7];
extern int FARDATA png_pass_height[7];
*/
#endif /* PNG_NO_EXTERN */
/* Three color definitions. The order of the red, green, and blue, (and the
* exact size) is not important, although the size of the fields need to
* be png_byte or png_uint_16 (as defined below).
*/
typedef struct png_color_struct
{
png_byte red;
png_byte green;
png_byte blue;
} png_color;
typedef png_color FAR * png_colorp;
typedef png_color FAR * FAR * png_colorpp;
typedef struct png_color_16_struct
{
png_byte index; /* used for palette files */
png_uint_16 red; /* for use in red green blue files */
png_uint_16 green;
png_uint_16 blue;
png_uint_16 gray; /* for use in grayscale files */
} png_color_16;
typedef png_color_16 FAR * png_color_16p;
typedef png_color_16 FAR * FAR * png_color_16pp;
typedef struct png_color_8_struct
{
png_byte red; /* for use in red green blue files */
png_byte green;
png_byte blue;
png_byte gray; /* for use in grayscale files */
png_byte alpha; /* for alpha channel files */
} png_color_8;
typedef png_color_8 FAR * png_color_8p;
typedef png_color_8 FAR * FAR * png_color_8pp;
/* png_text holds the text in a PNG file, and whether they are compressed
in the PNG file or not. The "text" field points to a regular C string. */
typedef struct png_text_struct
{
int compression; /* compression value, see PNG_TEXT_COMPRESSION_ */
png_charp key; /* keyword, 1-79 character description of "text" */
png_charp text; /* comment, may be an empty string (ie "") */
png_size_t text_length; /* length of "text" field */
} png_text;
typedef png_text FAR * png_textp;
typedef png_text FAR * FAR * png_textpp;
/* Supported compression types for text in PNG files (tEXt, and zTXt).
* The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
#define PNG_TEXT_COMPRESSION_NONE_WR -3
#define PNG_TEXT_COMPRESSION_zTXt_WR -2
#define PNG_TEXT_COMPRESSION_NONE -1
#define PNG_TEXT_COMPRESSION_zTXt 0
#define PNG_TEXT_COMPRESSION_LAST 1 /* Not a valid value */
/* png_time is a way to hold the time in an machine independent way.
* Two conversions are provided, both from time_t and struct tm. There
* is no portable way to convert to either of these structures, as far
* as I know. If you know of a portable way, send it to me. As a side
* note - PNG is Year 2000 compliant!
*/
typedef struct png_time_struct
{
png_uint_16 year; /* full year, as in, 1995 */
png_byte month; /* month of year, 1 - 12 */
png_byte day; /* day of month, 1 - 31 */
png_byte hour; /* hour of day, 0 - 23 */
png_byte minute; /* minute of hour, 0 - 59 */
png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
} png_time;
typedef png_time FAR * png_timep;
typedef png_time FAR * FAR * png_timepp;
/* png_info is a structure that holds the information in a PNG file so
* that the application can find out the characteristics of the image.
* If you are reading the file, this structure will tell you what is
* in the PNG file. If you are writing the file, fill in the information
* you want to put into the PNG file, then call png_write_info().
* The names chosen should be very close to the PNG specification, so
* consult that document for information about the meaning of each field.
*
* With libpng < 0.95, it was only possible to directly set and read the
* the values in the png_info_struct, which meant that the contents and
* order of the values had to remain fixed. With libpng 0.95 and later,
* however, there are now functions that abstract the contents of
* png_info_struct from the application, so this makes it easier to use
* libpng with dynamic libraries, and even makes it possible to use
* libraries that don't have all of the libpng ancillary chunk-handing
* functionality.
*
* In any case, the order of the parameters in png_info_struct should NOT
* be changed for as long as possible to keep compatibility with applications
* that use the old direct-access method with png_info_struct.
*/
typedef struct png_info_struct
{
/* the following are necessary for every PNG file */
png_uint_32 width; /* width of image in pixels (from IHDR) */
png_uint_32 height; /* height of image in pixels (from IHDR) */
png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
/* The following is informational only on read, and not used on writes. */
png_byte channels; /* number of data channels per pixel (1, 3, 4)*/
png_byte pixel_depth; /* number of bits per pixel */
png_byte spare_byte; /* to align the data, and for future use */
png_byte signature[8]; /* magic bytes read by libpng from start of file */
/* The rest of the data is optional. If you are reading, check the
* valid field to see if the information in these are valid. If you
* are writing, set the valid field to those chunks you want written,
* and initialize the appropriate fields below.
*/
#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED) || \
defined(PNG_READ_GAMMA_SUPPORTED)
/* The gAMA chunk describes the gamma characteristics of the system
* on which the image was created, normally in the range [1.0, 2.5].
* Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
*/
float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
#endif /* PNG_READ_gAMA_SUPPORTED || PNG_WRITE_gAMA_SUPPORTED */
#if defined(PNG_READ_sRGB_SUPPORTED) || defined(PNG_WRITE_sRGB_SUPPORTED)
/* GR-P, 0.96a */
/* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
#endif /* PNG_READ_sRGB_SUPPORTED || PNG_WRITE_sRGB_SUPPORTED */
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
/* The tEXt and zTXt chunks contain human-readable textual data in
* uncompressed and compressed forms, respectively. The data in "text"
* is an array of pointers to uncompressed, null-terminated C strings.
* Each chunk has a keyword that describes the textual data contained
* in that chunk. Keywords are not required to be unique, and the text
* string may be empty. Any number of text chunks may be in an image.
*/
int num_text; /* number of comments read/to write */
int max_text; /* current size of text array */
png_textp text; /* array of comments read/to write */
#endif /* PNG_READ_OR_WRITE_tEXt_OR_zTXt_SUPPORTED */
#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
/* The tIME chunk holds the last time the displayed image data was
* modified. See the png_time struct for the contents of this struct.
*/
png_time mod_time;
#endif /* PNG_READ_tIME_SUPPORTED || PNG_WRITE_tIME_SUPPORTED */
#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
/* The sBIT chunk specifies the number of significant high-order bits
* in the pixel data. Values are in the range [1, bit_depth], and are
* only specified for the channels in the pixel data. The contents of
* the low-order bits is not specified. Data is valid if
* (valid & PNG_INFO_sBIT) is non-zero.
*/
png_color_8 sig_bit; /* significant bits in color channels */
#endif /* PNG_READ_sBIT_SUPPORTED || PNG_WRITE_sBIT_SUPPORTED */
#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED) || \
defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
/* The tRNS chunk supplies transparency data for paletted images and
* other image types that don't need a full alpha channel. There are
* "num_trans" transparency values for a paletted image, stored in the
* same order as the palette colors, starting from index 0. Values
* for the data are in the range [0, 255], ranging from fully transparent
* to fully opaque, respectively. For non-paletted images, there is a
* single color specified that should be treated as fully transparent.
* Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
*/
png_bytep trans; /* transparent values for paletted image */
png_color_16 trans_values; /* transparent color for non-palette image */
#endif /* PNG_READ_tRNS_SUPPORTED || PNG_WRITE_tRNS_SUPPORTED */
#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED) || \
defined(PNG_READ_BACKGROUND_SUPPORTED)
/* The bKGD chunk gives the suggested image background color if the
* display program does not have its own background color and the image
* is needs to composited onto a background before display. The colors
* in "background" are normally in the same color space/depth as the
* pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
*/
png_color_16 background;
#endif /* PNG_READ_bKGD_SUPPORTED || PNG_WRITE_bKGD_SUPPORTED */
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
/* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
* and downwards from the top-left corner of the display, page, or other
* application-specific co-ordinate space. See the PNG_OFFSET_ defines
* below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
*/
png_uint_32 x_offset; /* x offset on page */
png_uint_32 y_offset; /* y offset on page */
png_byte offset_unit_type; /* offset units type */
#endif /* PNG_READ_oFFs_SUPPORTED || PNG_WRITE_oFFs_SUPPORTED */
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
/* The pHYs chunk gives the physical pixel density of the image for
* display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
* defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
*/
png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
png_uint_32 y_pixels_per_unit; /* vertical pixel density */
png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
#endif /* PNG_READ_pHYs_SUPPORTED || PNG_WRITE_pHYs_SUPPORTED */
#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
/* The hIST chunk contains the relative frequency or importance of the
* various palette entries, so that a viewer can intelligently select a
* reduced-color palette, if required. Data is an array of "num_palette"
* values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
* is non-zero.
*/
png_uint_16p hist;
#endif /* PNG_READ_hIST_SUPPORTED || PNG_WRITE_hIST_SUPPORTED */
#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
/* The cHRM chunk describes the CIE color characteristics of the monitor
* on which the PNG was created. This data allows the viewer to do gamut
* mapping of the input image to ensure that the viewer sees the same
* colors in the image as the creator. Values are in the range
* [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
*/
float x_white;
float y_white;
float x_red;
float y_red;
float x_green;
float y_green;
float x_blue;
float y_blue;
#endif /* PNG_READ_cHRM_SUPPORTED || PNG_WRITE_cHRM_SUPPORTED */
#if defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED)
/* The pCAL chunk describes a transformation between the stored pixel
* values and original physcical data values used to create the image.
* The integer range [0, 2^bit_depth - 1] maps to the floating-point
* range given by [pcal_X0, pcal_X1], and are further transformed by a
* (possibly non-linear) transformation function given by "pcal_type"
* and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
* defines below, and the PNG-Group's Scientific Visualization extension
* chunks document png-scivis-19970203 for a complete description of the
* transformations and how they should be implemented, as well as the
* png-extensions document for a description of the ASCII parameter
* strings. Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
*/
png_charp pcal_purpose; /* pCAL chunk description string */
png_int_32 pcal_X0; /* minimum value */
png_int_32 pcal_X1; /* maximum value */
png_charp pcal_units; /* Latin-1 string giving physical units */
png_charpp pcal_params; /* ASCII strings containing parameter values */
png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
png_byte pcal_nparams; /* number of parameters given in pcal_params */
#endif /* PNG_READ_pCAL_SUPPORTED || PNG_WRITE_pCAL_SUPPORTED */
} png_info;
typedef png_info FAR * png_infop;
typedef png_info FAR * FAR * png_infopp;
/* These describe the color_type field in png_info. */
/* color type masks */
#define PNG_COLOR_MASK_PALETTE 1
#define PNG_COLOR_MASK_COLOR 2
#define PNG_COLOR_MASK_ALPHA 4
/* color types. Note that not all combinations are legal */
#define PNG_COLOR_TYPE_GRAY 0
#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
/* This is for compression type. PNG 1.0 only defines the single type. */
#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
/* This is for filter type. PNG 1.0 only defines the single type. */
#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
/* These are for the interlacing type. These values should NOT be changed. */
#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
#define PNG_INTERLACE_LAST 2 /* Not a valid value */
/* These are for the oFFs chunk. These values should NOT be changed. */
#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
#define PNG_OFFSET_LAST 2 /* Not a valid value */
/* These are for the pCAL chunk. These values should NOT be changed. */
#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
#define PNG_EQUATION_LAST 4 /* Not a valid value */
/* These are for the pHYs chunk. These values should NOT be changed. */
#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
#define PNG_RESOLUTION_METER 1 /* pixels/meter */
#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
/* These are for the sRGB chunk. These values should NOT be changed. */
#define PNG_sRGB_INTENT_SATURATION 0
#define PNG_sRGB_INTENT_PERCEPTUAL 1
#define PNG_sRGB_INTENT_ABSOLUTE 2
#define PNG_sRGB_INTENT_RELATIVE 3
#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
/* 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_ defines should NOT be changed.
*/
#define PNG_INFO_gAMA 0x0001
#define PNG_INFO_sBIT 0x0002
#define PNG_INFO_cHRM 0x0004
#define PNG_INFO_PLTE 0x0008
#define PNG_INFO_tRNS 0x0010
#define PNG_INFO_bKGD 0x0020
#define PNG_INFO_hIST 0x0040
#define PNG_INFO_pHYs 0x0080
#define PNG_INFO_oFFs 0x0100
#define PNG_INFO_tIME 0x0200
#define PNG_INFO_pCAL 0x0400
#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
/* This is used for the transformation routines, as some of them
* change these values for the row. It also should enable using
* the routines for other purposes.
*/
typedef struct png_row_info_struct
{
png_uint_32 width; /* width of row */
png_uint_32 rowbytes; /* number of bytes in row */
png_byte color_type; /* color type of row */
png_byte bit_depth; /* bit depth of row */
png_byte channels; /* number of channels (1, 2, 3, or 4) */
png_byte pixel_depth; /* bits per pixel (depth * channels) */
} png_row_info;
typedef png_row_info FAR * png_row_infop;
typedef png_row_info FAR * FAR * png_row_infopp;
/* These are the function types for the I/O functions and for the functions
* that allow the user to override the default I/O functions with his or her
* own. The png_error_ptr type should match that of user-supplied warning
* and error functions, while the png_rw_ptr type should match that of the
* user read/write data functions.
*/
typedef struct png_struct_def png_struct;
typedef png_struct FAR * png_structp;
typedef void (*png_error_ptr) PNGARG((png_structp, png_const_charp));
typedef void (*png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
typedef void (*png_flush_ptr) PNGARG((png_structp));
typedef void (*png_read_status_ptr) PNGARG((png_structp, png_uint_32, int));
typedef void (*png_write_status_ptr) PNGARG((png_structp, png_uint_32, int));
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
typedef void (*png_progressive_info_ptr) PNGARG((png_structp, png_infop));
typedef void (*png_progressive_end_ptr) PNGARG((png_structp, png_infop));
typedef void (*png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
png_uint_32, int));
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
typedef void (*png_user_transform_ptr) PNGARG((png_structp,
png_row_infop, png_bytep));
#endif /* PNG_READ|WRITE_USER_TRANSFORM_SUPPORTED */
typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
typedef void (*png_free_ptr) PNGARG((png_structp, png_structp));
/* The structure that holds the information to read and write PNG files.
* The only people who need to care about what is inside of this are the
* people who will be modifying the library for their own special needs.
* It should NOT be accessed directly by an application, except to store
* the jmp_buf.
*/
struct png_struct_def
{
jmp_buf jmpbuf; /* used in png_error */
png_error_ptr error_fn; /* function for printing errors and aborting */
png_error_ptr warning_fn; /* function for printing warnings */
png_voidp error_ptr; /* user supplied struct for error functions */
png_rw_ptr write_data_fn; /* function for writing output data */
png_rw_ptr read_data_fn; /* function for reading input data */
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
png_user_transform_ptr read_user_transform_fn; /* user read transform */
png_user_transform_ptr write_user_transform_fn; /* user write transform */
#endif
png_voidp io_ptr; /* ptr to application struct for I/O functions*/
png_uint_32 mode; /* tells us where we are in the PNG file */
png_uint_32 flags; /* flags indicating various things to libpng */
png_uint_32 transformations; /* which transformations to perform */
z_stream zstream; /* pointer to decompression structure (below) */
png_bytep zbuf; /* buffer for zlib */
png_size_t zbuf_size; /* size of zbuf */
int zlib_level; /* holds zlib compression level */
int zlib_method; /* holds zlib compression method */
int zlib_window_bits; /* holds zlib compression window bits */
int zlib_mem_level; /* holds zlib compression memory level */
int zlib_strategy; /* holds zlib compression strategy */
png_uint_32 width; /* width of image in pixels */
png_uint_32 height; /* height of image in pixels */
png_uint_32 num_rows; /* number of rows in current pass */
png_uint_32 usr_width; /* width of row at start of write */
png_uint_32 rowbytes; /* size of row in bytes */
png_uint_32 irowbytes; /* size of current interlaced row in bytes */
png_uint_32 iwidth; /* width of current interlaced row in pixels */
png_uint_32 row_number; /* current row in interlace pass */
png_bytep prev_row; /* buffer to save previous (unfiltered) row */
png_bytep row_buf; /* buffer to save current (unfiltered) row */
png_bytep sub_row; /* buffer to save "sub" row when filtering */
png_bytep up_row; /* buffer to save "up" row when filtering */
png_bytep avg_row; /* buffer to save "avg" row when filtering */
png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
png_row_info row_info; /* used for transformation routines */
png_uint_32 idat_size; /* current IDAT size for read */
png_uint_32 crc; /* current chunk CRC value */
png_colorp palette; /* palette from the input file */
png_uint_16 num_palette; /* number of color entries in palette */
png_uint_16 num_trans; /* number of transparency values */
png_byte chunk_name[5]; /* null-terminated name of current chunk */
png_byte compression; /* file compression type (always 0) */
png_byte filter; /* file filter type (always 0) */
png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
png_byte pass; /* current interlace pass (0 - 6) */
png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
png_byte color_type; /* color type of file */
png_byte bit_depth; /* bit depth of file */
png_byte usr_bit_depth; /* bit depth of users row */
png_byte pixel_depth; /* number of bits per pixel */
png_byte channels; /* number of channels in file */
png_byte usr_channels; /* channels at start of write */
png_byte sig_bytes; /* magic bytes read/written from start of file */
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
png_uint_16 filler; /* filler bytes for pixel expansion */
#endif /* PNG_READ_FILLER_SUPPORTED */
#if defined(PNG_READ_bKGD_SUPPORTED)
png_byte background_gamma_type;
float background_gamma;
png_color_16 background; /* background color in screen gamma space */
#if defined(PNG_READ_GAMMA_SUPPORTED)
png_color_16 background_1; /* background normalized to gamma 1.0 */
#endif /* PNG_READ_GAMMA && PNG_READ_bKGD_SUPPORTED */
#endif /* PNG_READ_bKGD_SUPPORTED */
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
png_flush_ptr output_flush_fn;/* Function for flushing output */
png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
png_uint_32 flush_rows; /* number of rows written since last flush */
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
float gamma; /* file gamma value */
float screen_gamma; /* screen gamma value (display_gamma/viewing_gamma */
#endif /* PNG_READ_GAMMA_SUPPORTED */
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
png_bytep gamma_table; /* gamma table for 8 bit depth files */
png_bytep gamma_from_1; /* converts from 1.0 to screen */
png_bytep gamma_to_1; /* converts from file to 1.0 */
png_uint_16pp gamma_16_table; /* gamma table for 16 bit depth files */
png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
#endif /* PNG_READ_GAMMA_SUPPORTED || PNG_WRITE_GAMMA_SUPPORTED */
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined (PNG_READ_sBIT_SUPPORTED)
png_color_8 sig_bit; /* significant bits in each available channel */
#endif /* PNG_READ_GAMMA_SUPPORTED || PNG_READ_sBIT_SUPPORTED */
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
png_color_8 shift; /* shift for significant bit tranformation */
#endif /* PNG_READ_SHIFT_SUPPORTED || PNG_WRITE_SHIFT_SUPPORTED */
#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
|| defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
png_bytep trans; /* transparency values for paletted files */
png_color_16 trans_values; /* transparency values for non-paletted files */
#endif /* PNG_READ|WRITE_tRNS_SUPPORTED||PNG_READ_EXPAND|BACKGROUND_SUPPORTED */
png_read_status_ptr read_row_fn; /* called after each row is decoded */
png_write_status_ptr write_row_fn; /* called after each row is encoded */
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
png_progressive_info_ptr info_fn; /* called after header data fully read */
png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
png_progressive_end_ptr end_fn; /* called after image is complete */
png_bytep save_buffer_ptr; /* current location in save_buffer */
png_bytep save_buffer; /* buffer for previously read data */
png_bytep current_buffer_ptr; /* current location in current_buffer */
png_bytep current_buffer; /* buffer for recently used data */
png_uint_32 push_length; /* size of current input chunk */
png_uint_32 skip_length; /* bytes to skip in input data */
png_size_t save_buffer_size; /* amount of data now in save_buffer */
png_size_t save_buffer_max; /* total size of save_buffer */
png_size_t buffer_size; /* total amount of available input data */
png_size_t current_buffer_size; /* amount of data now in current_buffer */
int process_mode; /* what push library is currently doing */
int cur_palette; /* current push library palette index */
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
png_size_t current_text_size; /* current size of text input data */
png_size_t current_text_left; /* how much text left to read in input */
png_charp current_text; /* current text chunk buffer */
png_charp current_text_ptr; /* current location in current_text */
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_READ_tEXt/zTXt_SUPPORTED */
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
/* for the Borland special 64K segment handler */
png_bytepp offset_table_ptr;
png_bytep offset_table;
png_uint_16 offset_table_number;
png_uint_16 offset_table_count;
png_uint_16 offset_table_count_free;
#endif /* __TURBOC__&&!_Windows&&!__FLAT__ */
#if defined(PNG_READ_DITHER_SUPPORTED)
png_bytep palette_lookup; /* lookup table for dithering */
png_bytep dither_index; /* index translation for palette files */
#endif /* PNG_READ_DITHER_SUPPORTED */
#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_READ_hIST_SUPPORTED)
png_uint_16p hist; /* histogram */
#endif
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
png_byte heuristic_method; /* heuristic for row filter selection */
png_byte num_prev_filters; /* number of weights for previous rows */
png_bytep prev_filters; /* filter type(s) of previous row(s) */
png_uint_16p filter_weights; /* weight(s) for previous line(s) */
png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
png_uint_16p filter_costs; /* relative filter calculation cost */
png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
#if defined(PNG_TIME_RFC1123_SUPPORTED)
png_charp time_buffer; /* String to hold RFC 1123 time text */
#endif /* PNG_TIME_RFC1123_SUPPORTED */
#ifdef PNG_USER_MEM_SUPPORTED
png_voidp mem_ptr; /* user supplied struct for mem functions */
png_malloc_ptr malloc_fn; /* function for allocating memory */
png_free_ptr free_fn; /* function for freeing memory */
#endif /* PNG_USER_MEM_SUPPORTED */
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
png_byte rgb_to_gray_status;
png_byte rgb_to_gray_red_coeff;
png_byte rgb_to_gray_green_coeff;
png_byte rgb_to_gray_blue_coeff;
#endif
};
typedef png_struct FAR * FAR * png_structpp;
/* Here are the function definitions most commonly used. This is not
* the place to find out how to use libpng. See libpng.txt for the
* full explanation, see example.c for the summary. This just provides
* a simple one line of the use of each function.
*/
/* Tell lib we have already handled the first magic bytes.
* Handling more than 8 bytes from the beginning of the file is an error.
*/
extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
int num_bytes));
/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
* PNG file. Returns zero if the supplied bytes match the 8-byte PNG
* signature, and non-zero otherwise. Having num_to_check == 0 or
* start > 7 will always fail (ie return non-zero).
*/
extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
png_size_t num_to_check));
/* Simple signature checking function. This is the same as calling
* png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
*/
extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
/* Allocate and initialize png_ptr struct for reading, and any other memory. */
extern PNG_EXPORT(png_structp,png_create_read_struct)
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn));
/* Allocate and initialize png_ptr struct for writing, and any other memory */
extern PNG_EXPORT(png_structp,png_create_write_struct)
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn));
#ifdef PNG_USER_MEM_SUPPORTED
extern PNG_EXPORT(png_structp,png_create_read_struct_2)
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
png_malloc_ptr malloc_fn, png_free_ptr free_fn));
extern PNG_EXPORT(png_structp,png_create_write_struct_2)
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
png_malloc_ptr malloc_fn, png_free_ptr free_fn));
#endif
/* Write a PNG chunk - size, type, (optional) data, CRC. */
extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
png_bytep chunk_name, png_bytep data, png_size_t length));
/* Write the start of a PNG chunk - length and chunk name. */
extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
png_bytep chunk_name, png_uint_32 length));
/* Write the data of a PNG chunk started with png_write_chunk_start(). */
extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
png_bytep data, png_size_t length));
/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
/* Allocate and initialize the info structure */
extern PNG_EXPORT(png_infop,png_create_info_struct)
PNGARG((png_structp png_ptr));
/* Initialize the info structure (old interface - NOT DLL EXPORTED) */
extern void png_info_init PNGARG((png_infop info_ptr));
/* Writes all the PNG information before the image. */
extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* read the information before the actual image data. */
extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
png_infop info_ptr));
#if defined(PNG_TIME_RFC1123_SUPPORTED)
extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
PNGARG((png_structp png_ptr, png_timep ptime));
#endif /* PNG_TIME_RFC1123_SUPPORTED */
#if defined(PNG_WRITE_tIME_SUPPORTED)
/* convert from a struct tm to png_time */
extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
struct tm FAR * ttime));
/* convert from time_t to png_time. Uses gmtime() */
extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
time_t ttime));
#endif /* PNG_WRITE_tIME_SUPPORTED */
#if defined(PNG_READ_EXPAND_SUPPORTED)
/* Expand data to 24 bit RGB, or 8 bit grayscale, with alpha if available. */
extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_EXPAND_SUPPORTED */
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* Use blue, green, red order for pixels. */
extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_BGR_SUPPORTED || PNG_WRITE_BGR_SUPPORTED */
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
/* Expand the grayscale to 24 bit RGB if necessary. */
extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_GRAY_TO_RGB_SUPPORTED */
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
/* Reduce RGB to grayscale. */
extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
int error_action, float red, float green ));
extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
png_ptr));
#endif /* PNG_READ_RGB_TO_GRAY_SUPPORTED */
extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
png_colorp palette));
#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_STRIP_ALPHA_SUPPORTED */
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_SWAP_ALPHA_SUPPORTED || PNG_WRITE_SWAP_ALPHA_SUPPORTED */
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_INVERT_ALPHA_SUPPORTED || PNG_WRITE_INVERT_ALPHA_SUPPORTED */
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
/* Add a filler byte to 24-bit RGB images. */
extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
png_uint_32 filler, int flags));
/* The values of the PNG_FILLER_ defines should NOT be changed */
#define PNG_FILLER_BEFORE 0
#define PNG_FILLER_AFTER 1
#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* Swap bytes in 16 bit depth files. */
extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_SWAP_SUPPORTED || PNG_WRITE_SWAP_SUPPORTED */
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
/* Use 1 byte per pixel in 1, 2, or 4 bit depth files. */
extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_PACK_SUPPORTED || PNG_WRITE_PACK_SUPPORTED */
#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
/* Swap packing order of pixels in bytes. */
extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_PACKSWAP_SUPPORTED || PNG_WRITE_PACKSWAP_SUPPOR */
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
/* Converts files to legal bit depths. */
extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
png_color_8p true_bits));
#endif /* PNG_READ_SHIFT_SUPPORTED || PNG_WRITE_SHIFT_SUPPORTED */
#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* Have the code handle the interlacing. Returns the number of passes. */
extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_INTERLACING_SUPPORTED || PNG_WRITE_INTERLACING_SUPPORTED */
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
/* Invert monocrome files */
extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_INVERT_SUPPORTED || PNG_WRITE_INVERT_SUPPORTED */
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
/* Handle alpha and tRNS by replacing with a background color. */
extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
png_color_16p background_color, int background_gamma_code,
int need_expand, double background_gamma));
#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
#define PNG_BACKGROUND_GAMMA_SCREEN 1
#define PNG_BACKGROUND_GAMMA_FILE 2
#define PNG_BACKGROUND_GAMMA_UNIQUE 3
#endif /* PNG_READ_BACKGROUND_SUPPORTED */
#if defined(PNG_READ_16_TO_8_SUPPORTED)
/* strip the second byte of information from a 16 bit depth file. */
extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
#endif /* PNG_READ_16_TO_8_SUPPORTED */
#if defined(PNG_READ_DITHER_SUPPORTED)
/* Turn on dithering, and reduce the palette to the number of colors available. */
extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
png_colorp palette, int num_palette, int maximum_colors,
png_uint_16p histogram, int full_dither));
#endif /* PNG_READ_DITHER_SUPPORTED */
#if defined(PNG_READ_GAMMA_SUPPORTED)
/* Handle gamma correction. Screen_gamma=(display_gamma/viewing_gamma) */
extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
double screen_gamma, double default_file_gamma));
#endif /* PNG_READ_GAMMA_SUPPORTED */
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
/* Set how many lines between output flushes - 0 for no flushing */
extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
/* Flush the current PNG output buffer */
extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
/* optional update palette with requested transformations */
extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
/* optional call to update the users info structure */
extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* read a one or more rows of image data.*/
extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
/* read a row of data.*/
extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
png_bytep row,
png_bytep display_row));
/* read the whole image into memory at once. */
extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
png_bytepp image));
/* write a row of image data */
extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
png_bytep row));
/* write a few rows of image data */
extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
png_bytepp row, png_uint_32 num_rows));
/* write the image data */
extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
png_bytepp image));
/* writes the end of the PNG file. */
extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* read the end of the PNG file. */
extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* free any memory associated with the png_info_struct */
extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
png_infopp info_ptr_ptr));
/* free any memory associated with the png_struct and the png_info_structs */
extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
/* free all memory used by the read (old method - NOT DLL EXPORTED) */
extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
png_infop end_info_ptr));
/* free any memory associated with the png_struct and the png_info_structs */
extern PNG_EXPORT(void,png_destroy_write_struct)
PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
/* free any memory used in info_ptr struct (old method - NOT DLL EXPORTED) */
extern void png_write_destroy_info PNGARG((png_infop info_ptr));
/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
extern void png_write_destroy PNGARG((png_structp png_ptr));
/* set the libpng method of handling chunk CRC errors */
extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
int crit_action, int ancil_action));
/* Values for png_set_crc_action() to say how to handle CRC errors in
* ancillary and critical chunks, and whether to use the data contained
* therein. Note that it is impossible to "discard" data in a critical
* chunk. For versions prior to 0.90, the action was always error/quit,
* whereas in version 0.90 and later, the action for CRC errors in ancillary
* chunks is warn/discard. These values should NOT be changed.
*
* value action:critical action:ancillary
*/
#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
/* These functions give the user control over the scan-line filtering in
* libpng and the compression methods used by zlib. These functions are
* mainly useful for testing, as the defaults should work with most users.
* Those users who are tight on memory or want faster performance at the
* expense of compression can modify them. See the compression library
* header file (zlib.h) for an explination of the compression functions.
*/
/* set the filtering method(s) used by libpng. Currently, the only valid
* value for "method" is 0.
*/
extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
int filters));
/* Flags for png_set_filter() to say which filters to use. The flags
* are chosen so that they don't conflict with real filter types
* below, in case they are supplied instead of the #defined constants.
* These values should NOT be changed.
*/
#define PNG_NO_FILTERS 0x00
#define PNG_FILTER_NONE 0x08
#define PNG_FILTER_SUB 0x10
#define PNG_FILTER_UP 0x20
#define PNG_FILTER_AVG 0x40
#define PNG_FILTER_PAETH 0x80
#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
PNG_FILTER_AVG | PNG_FILTER_PAETH)
/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
* These defines should NOT be changed.
*/
#define PNG_FILTER_VALUE_NONE 0
#define PNG_FILTER_VALUE_SUB 1
#define PNG_FILTER_VALUE_UP 2
#define PNG_FILTER_VALUE_AVG 3
#define PNG_FILTER_VALUE_PAETH 4
#define PNG_FILTER_VALUE_LAST 5
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
* defines, either the default (minimum-sum-of-absolute-differences), or
* the experimental method (weighted-minimum-sum-of-absolute-differences).
*
* Weights are factors >= 1.0, indicating how important it is to keep the
* filter type consistent between rows. Larger numbers mean the current
* filter is that many times as likely to be the same as the "num_weights"
* previous filters. This is cumulative for each previous row with a weight.
* There needs to be "num_weights" values in "filter_weights", or it can be
* NULL if the weights aren't being specified. Weights have no influence on
* the selection of the first row filter. Well chosen weights can (in theory)
* improve the compression for a given image.
*
* Costs are factors >= 1.0 indicating the relative decoding costs of a
* filter type. Higher costs indicate more decoding expense, and are
* therefore less likely to be selected over a filter with lower computational
* costs. There needs to be a value in "filter_costs" for each valid filter
* type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
* setting the costs. Costs try to improve the speed of decompression without
* unduly increasing the compressed image size.
*
* A negative weight or cost indicates the default value is to be used, and
* values in the range [0.0, 1.0) indicate the value is to remain unchanged.
* The default values for both weights and costs are currently 1.0, but may
* change if good general weighting/cost heuristics can be found. If both
* the weights and costs are set to 1.0, this degenerates the WEIGHTED method
* to the UNWEIGHTED method, but with added encoding time/computation.
*/
extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
int heuristic_method, int num_weights, png_doublep filter_weights,
png_doublep filter_costs));
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
/* Heuristic used for row filter selection. These defines should NOT be
* changed.
*/
#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
/* Set the library compression level. Currently, valid values range from
* 0 - 9, corresponding directly to the zlib compression levels 0 - 9
* (0 - no compression, 9 - "maximal" compression). Note that tests have
* shown that zlib compression levels 3-6 usually perform as well as level 9
* for PNG images, and do considerably fewer caclulations. In the future,
* these values may not correspond directly to the zlib compression levels.
*/
extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
int level));
extern PNG_EXPORT(void,png_set_compression_mem_level)
PNGARG((png_structp png_ptr, int mem_level));
extern PNG_EXPORT(void,png_set_compression_strategy)
PNGARG((png_structp png_ptr, int strategy));
extern PNG_EXPORT(void,png_set_compression_window_bits)
PNGARG((png_structp png_ptr, int window_bits));
extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
int method));
/* These next functions are called for input/output, memory, and error
* handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
* and call standard C I/O routines such as fread(), fwrite(), and
* fprintf(). These functions can be made to use other I/O routines
* at run time for those applications that need to handle I/O in a
* different manner by calling png_set_???_fn(). See libpng.txt for
* more information.
*/
#if !defined(PNG_NO_STDIO)
/* Initialize the input/output for the PNG file to the default functions. */
extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, FILE *fp));
#endif
/* Replace the (error and abort), and warning functions with user
* supplied functions. If no messages are to be printed you must still
* write and use replacement functions. The replacement error_fn should
* still do a longjmp to the last setjmp location if you are using this
* method of error handling. If error_fn or warning_fn is NULL, the
* default function will be used.
*/
extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
/* Return the user pointer associated with the error functions */
extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
/* Replace the default data output functions with a user supplied one(s).
* If buffered output is not used, then output_flush_fn can be set to NULL.
* If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
* output_flush_fn will be ignored (and thus can be NULL).
*/
extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
/* Replace the default data input function with a user supplied one. */
extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
png_voidp io_ptr, png_rw_ptr read_data_fn));
/* Return the user pointer associated with the I/O functions */
extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
png_read_status_ptr read_row_fn));
extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
png_write_status_ptr write_row_fn));
#ifdef PNG_USER_MEM_SUPPORTED
/* Replace the default memory allocation functions with user supplied one(s). */
extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
/* Return the user pointer associated with the memory functions */
extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
#endif /* PNG_USER_MEM_SUPPORTED */
#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
png_ptr, png_user_transform_ptr read_user_transform_fn));
#endif
#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
png_ptr, png_user_transform_ptr write_user_transform_fn));
#endif
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
/* Sets the function callbacks for the push reader, and a pointer to a
* user-defined structure available to the callback functions.
*/
extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
png_voidp progressive_ptr,
png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
png_progressive_end_ptr end_fn));
/* returns the user pointer associated with the push read functions */
extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
PNGARG((png_structp png_ptr));
/* function to be called when data becomes available */
extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
/* function that combines rows. Not very much different than the
* png_combine_row() call. Is this even used?????
*/
extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
png_bytep old_row, png_bytep new_row));
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
png_uint_32 size));
/* frees a pointer allocated by png_malloc() */
extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
#ifdef PNG_USER_MEM_SUPPORTED
extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
png_uint_32 size));
extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
png_voidp ptr));
#endif /* PNG_USER_MEM_SUPPORTED */
extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
png_voidp s1, png_voidp s2, png_uint_32 size));
extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
png_voidp s1, int value, png_uint_32 size));
#if defined(USE_FAR_KEYWORD) /* memory model conversion function */
extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
int check));
#endif /* USE_FAR_KEYWORD */
/* Fatal error in PNG image of libpng - can't continue */
extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
png_const_charp error));
/* The same, but the chunk name is prepended to the error string. */
extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
png_const_charp error));
/* Non-fatal error in libpng. Can continue, but may have a problem. */
extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
png_const_charp message));
/* Non-fatal error in libpng, chunk name is prepended to message. */
extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
png_const_charp message));
/* The png_set_ functions are for storing values in the png_info_struct.
* Similarly, the png_get_ calls are used to read values from the
* png_info_struct, either storing the parameters in the passed variables, or
* setting pointers into the png_info_struct where the data is stored. The
* png_get_ functions return a non-zero value if the data was available
* in info_ptr, or return zero and do not change any of the parameters if the
* data was not available.
*
* These functions should be used instead of directly accessing png_info
* to avoid problems with future changes in the size and internal layout of
* png_info_struct.
*/
/* Returns "flag" if chunk data is valid in info_ptr. */
extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 flag));
/* Returns number of bytes needed to hold a transformed row. */
extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* Returns number of color channels in image. */
extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
png_infop info_ptr));
#ifdef PNG_EASY_ACCESS_SUPPORTED
/* Returns image width in pixels. */
extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image height in pixels. */
extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image bit_depth. */
extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image color_type. */
extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image filter_type. */
extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image interlace_type. */
extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image compression_type. */
extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image resolution in pixels per meter, from pHYs chunk data. */
extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
png_ptr, png_infop info_ptr));
extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
png_ptr, png_infop info_ptr));
extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns pixel aspect ratio, computed from pHYs chunk data. */
extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
png_ptr, png_infop info_ptr));
/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
extern PNG_EXPORT(png_uint_32, png_get_x_offset_pixels) PNGARG((png_structp
png_ptr, png_infop info_ptr));
extern PNG_EXPORT(png_uint_32, png_get_y_offset_pixels) PNGARG((png_structp
png_ptr, png_infop info_ptr));
extern PNG_EXPORT(png_uint_32, png_get_x_offset_microns) PNGARG((png_structp
png_ptr, png_infop info_ptr));
extern PNG_EXPORT(png_uint_32, png_get_y_offset_microns) PNGARG((png_structp
png_ptr, png_infop info_ptr));
#endif /* PNG_EASY_ACCESS_SUPPORTED */
/* Returns pointer to signature string read from PNG header */
extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
png_infop info_ptr));
#if defined(PNG_READ_bKGD_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_color_16p *background));
#endif /* PNG_READ_bKGD_SUPPORTED */
#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED)
extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_color_16p background));
#endif /* PNG_READ_bKGD_SUPPORTED || PNG_WRITE_bKGD_SUPPORTED */
#if defined(PNG_READ_cHRM_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
png_infop info_ptr, double *white_x, double *white_y, double *red_x,
double *red_y, double *green_x, double *green_y, double *blue_x,
double *blue_y));
#endif /* PNG_READ_cHRM_SUPPORTED */
#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
png_infop info_ptr, double white_x, double white_y, double red_x,
double red_y, double green_x, double green_y, double blue_x, double blue_y));
#endif /* PNG_READ_cHRM_SUPPORTED || PNG_WRITE_cHRM_SUPPORTED */
#if defined(PNG_READ_gAMA_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
png_infop info_ptr, double *file_gamma));
#endif /* PNG_READ_gAMA_SUPPORTED */
#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
png_infop info_ptr, double file_gamma));
#endif /* PNG_READ_gAMA_SUPPORTED || PNG_WRITE_gAMA_SUPPORTED */
#if defined(PNG_READ_hIST_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_16p *hist));
#endif /* PNG_READ_hIST_SUPPORTED */
#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_16p hist));
#endif /* PNG_READ_hIST_SUPPORTED || PNG_WRITE_hIST_SUPPORTED */
extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
int *bit_depth, int *color_type, int *interlace_type,
int *compression_type, int *filter_type));
extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
int color_type, int interlace_type, int compression_type, int filter_type));
#if defined(PNG_READ_oFFs_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 *offset_x, png_uint_32 *offset_y,
int *unit_type));
#endif /* PNG_READ_oFFs_SUPPORTED */
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 offset_x, png_uint_32 offset_y,
int unit_type));
#endif /* PNG_READ_oFFs_SUPPORTED || PNG_WRITE_oFFs_SUPPORTED */
#if defined(PNG_READ_pCAL_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
int *type, int *nparams, png_charp *units, png_charpp *params));
#endif /* PNG_READ_pCAL_SUPPORTED */
#if defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED)
extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
int type, int nparams, png_charp units, png_charpp params));
#endif /* PNG_READ_pCAL_SUPPORTED || PNG_WRITE_pCAL_SUPPORTED */
#if defined(PNG_READ_pHYs_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
#endif /* PNG_READ_pHYs_SUPPORTED */
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
#endif /* PNG_READ_pHYs_SUPPORTED || PNG_WRITE_pHYs_SUPPORTED */
extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_colorp *palette, int *num_palette));
extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_colorp palette, int num_palette));
#if defined(PNG_READ_sBIT_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_color_8p *sig_bit));
#endif /* PNG_READ_sBIT_SUPPORTED */
#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_color_8p sig_bit));
#endif /* PNG_READ_sBIT_SUPPORTED || PNG_WRITE_sBIT_SUPPORTED */
#if defined(PNG_READ_sRGB_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
png_infop info_ptr, int *intent));
#endif /* PNG_READ_sRGB_SUPPORTED */
#if defined(PNG_READ_sRGB_SUPPORTED) || defined(PNG_WRITE_sRGB_SUPPORTED)
extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
png_infop info_ptr, int intent));
extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
png_infop info_ptr, int intent));
#endif /* PNG_READ_sRGB_SUPPORTED || PNG_WRITE_sRGB_SUPPORTED */
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
/* png_get_text also returns the number of text chunks in text_ptr */
extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_textp *text_ptr, int *num_text));
#endif /* PNG_READ_tEXt_SUPPORTED || PNG_READ_zTXt_SUPPORTED */
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_textp text_ptr, int num_text));
#endif /* PNG_READ_OR_WRITE_tEXt_OR_zTXt_SUPPORTED */
#if defined(PNG_READ_tIME_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_timep *mod_time));
#endif /* PNG_READ_tIME_SUPPORTED */
#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_timep mod_time));
#endif /* PNG_READ_tIME_SUPPORTED || PNG_WRITE_tIME_SUPPORTED */
#if defined(PNG_READ_tRNS_SUPPORTED)
extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_bytep *trans, int *num_trans,
png_color_16p *trans_values));
#endif /* PNG_READ_tRNS_SUPPORTED */
#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED)
extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
png_infop info_ptr, png_bytep trans, int num_trans,
png_color_16p trans_values));
#endif /* PNG_READ_tRNS_SUPPORTED || PNG_WRITE_tRNS_SUPPORTED */
/* Define PNG_DEBUG at compile time for debugging information. Higher
* numbers for PNG_DEBUG mean more debugging information. This has
* only been added since version 0.95 so it is not implemented throughout
* libpng yet, but more support will be added as needed.
*/
#ifdef PNG_DEBUG
#if (PNG_DEBUG > 0)
#ifndef PNG_DEBUG_FILE
#define PNG_DEBUG_FILE stderr
#endif /* PNG_DEBUG_FILE */
#define png_debug(l,m) if (PNG_DEBUG > l) \
fprintf(PNG_DEBUG_FILE,"%s"m,(l==1 ? "\t" : \
(l==2 ? "\t\t":(l>2 ? "\t\t\t":""))))
#define png_debug1(l,m,p1) if (PNG_DEBUG > l) \
fprintf(PNG_DEBUG_FILE,"%s"m,(l==1 ? "\t" : \
(l==2 ? "\t\t":(l>2 ? "\t\t\t":""))),p1)
#define png_debug2(l,m,p1,p2) if (PNG_DEBUG > l) \
fprintf(PNG_DEBUG_FILE,"%s"m,(l==1 ? "\t" : \
(l==2 ? "\t\t":(l>2 ? "\t\t\t":""))),p1,p2)
#endif /* (PNG_DEBUG > 0) */
#endif /* PNG_DEBUG */
#ifndef png_debug
#define png_debug(l, m)
#endif
#ifndef png_debug1
#define png_debug1(l, m, p1)
#endif
#ifndef png_debug2
#define png_debug2(l, m, p1, p2)
#endif
extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
#ifdef PNG_NO_EXTERN
/* this only gets included in png.c */
png_charp
png_get_header_version(png_structp png_ptr)
{
if(png_ptr == NULL)
/* silence compiler warning about unused png_ptr */ ;
return("\n libpng version 1.0.3 - January 14, 1999 (header)\n");
}
#endif
#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
/* With these routines we avoid an integer divide, which will be slower on
* most machines. However, it does take more operations than the corresponding
* divide method, so it may be slower on a few RISC systems. There are two
* shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
*
* Note that the rounding factors are NOT supposed to be the same! 128 and
* 32768 are correct for the NODIV code; 127 and 32767 are correct for the
* standard method.
*
* [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
*/
/* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
# define png_composite(composite, fg, alpha, bg) \
{ png_uint_16 temp = ((png_uint_16)(fg) * (png_uint_16)(alpha) + \
(png_uint_16)(bg)*(png_uint_16)(255 - \
(png_uint_16)(alpha)) + (png_uint_16)128); \
(composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
# define png_composite_16(composite, fg, alpha, bg) \
{ png_uint_32 temp = ((png_uint_32)(fg) * (png_uint_32)(alpha) + \
(png_uint_32)(bg)*(png_uint_32)(65535L - \
(png_uint_32)(alpha)) + (png_uint_32)32768L); \
(composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
#else /* standard method using integer division */
# define png_composite(composite, fg, alpha, bg) \
(composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
(png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
(png_uint_16)127) / 255)
# define png_composite_16(composite, fg, alpha, bg) \
(composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
(png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
(png_uint_32)32767) / (png_uint_32)65535L)
#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
/* These next functions are used internally in the code. They generally
* shouldn't be used unless you are writing code to add or replace some
* functionality in libpng. More information about most functions can
* be found in the files where the functions are located.
*/
#if defined(PNG_INTERNAL)
/* Various modes of operation. Note that after an init, mode is set to
* zero automatically when the structure is created.
*/
#define PNG_BEFORE_IHDR 0x00
#define PNG_HAVE_IHDR 0x01
#define PNG_HAVE_PLTE 0x02
#define PNG_HAVE_IDAT 0x04
#define PNG_AFTER_IDAT 0x08
#define PNG_HAVE_IEND 0x10
#define PNG_HAVE_gAMA 0x20
#define PNG_HAVE_cHRM 0x40
#define PNG_HAVE_sRGB 0x80
/* push model modes */
#define PNG_READ_SIG_MODE 0
#define PNG_READ_CHUNK_MODE 1
#define PNG_READ_IDAT_MODE 2
#define PNG_SKIP_MODE 3
#define PNG_READ_tEXt_MODE 4
#define PNG_READ_zTXt_MODE 5
#define PNG_READ_DONE_MODE 6
#define PNG_ERROR_MODE 7
/* flags for the transformations the PNG library does on the image data */
#define PNG_BGR 0x0001
#define PNG_INTERLACE 0x0002
#define PNG_PACK 0x0004
#define PNG_SHIFT 0x0008
#define PNG_SWAP_BYTES 0x0010
#define PNG_INVERT_MONO 0x0020
#define PNG_DITHER 0x0040
#define PNG_BACKGROUND 0x0080
#define PNG_BACKGROUND_EXPAND 0x0100
/* 0x0200 unused */
#define PNG_16_TO_8 0x0400
#define PNG_RGBA 0x0800
#define PNG_EXPAND 0x1000
#define PNG_GAMMA 0x2000
#define PNG_GRAY_TO_RGB 0x4000
#define PNG_FILLER 0x8000
#define PNG_PACKSWAP 0x10000L
#define PNG_SWAP_ALPHA 0x20000L
#define PNG_STRIP_ALPHA 0x40000L
#define PNG_INVERT_ALPHA 0x80000L
#define PNG_USER_TRANSFORM 0x100000L
#define PNG_RGB_TO_GRAY_ERR 0x200000L
#define PNG_RGB_TO_GRAY_WARN 0x400000L
#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
/* flags for png_create_struct */
#define PNG_STRUCT_PNG 0x0001
#define PNG_STRUCT_INFO 0x0002
/* Scaling factor for filter heuristic weighting calculations */
#define PNG_WEIGHT_SHIFT 8
#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
#define PNG_COST_SHIFT 3
#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
/* flags for the png_ptr->flags rather than declaring a byte for each one */
#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
#define PNG_FLAG_ZLIB_FINISHED 0x0020
#define PNG_FLAG_ROW_INIT 0x0040
#define PNG_FLAG_FILLER_AFTER 0x0080
#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
#define PNG_FLAG_FREE_PALETTE 0x1000
#define PNG_FLAG_FREE_TRANS 0x2000
#define PNG_FLAG_FREE_HIST 0x4000
#define PNG_FLAG_HAVE_CHUNK_HEADER 0x8000L
#define PNG_FLAG_WROTE_tIME 0x10000L
#define PNG_FLAG_BACKGROUND_IS_GRAY 0x20000L
#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
PNG_FLAG_CRC_ANCILLARY_NOWARN)
#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
PNG_FLAG_CRC_CRITICAL_IGNORE)
#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
PNG_FLAG_CRC_CRITICAL_MASK)
/* save typing and make code easier to understand */
#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
abs((int)((c1).green) - (int)((c2).green)) + \
abs((int)((c1).blue) - (int)((c2).blue)))
/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
/* place to hold the signature string for a PNG file. */
extern png_byte FARDATA png_sig[8];
/* Constant strings for known chunk types. If you need to add a chunk,
* add a string holding the name here. See png.c for more details. We
* can't selectively include these, since we still check for chunk in the
* wrong locations with these labels.
*/
extern png_byte FARDATA png_IHDR[5];
extern png_byte FARDATA png_IDAT[5];
extern png_byte FARDATA png_IEND[5];
extern png_byte FARDATA png_PLTE[5];
extern png_byte FARDATA png_bKGD[5];
extern png_byte FARDATA png_cHRM[5];
extern png_byte FARDATA png_gAMA[5];
extern png_byte FARDATA png_hIST[5];
extern png_byte FARDATA png_oFFs[5];
extern png_byte FARDATA png_pCAL[5];
extern png_byte FARDATA png_pHYs[5];
extern png_byte FARDATA png_sBIT[5];
extern png_byte FARDATA png_sRGB[5];
extern png_byte FARDATA png_tEXt[5];
extern png_byte FARDATA png_tIME[5];
extern png_byte FARDATA png_tRNS[5];
extern png_byte FARDATA png_zTXt[5];
#endif /* PNG_NO_EXTERN */
/* Inline macros to do direct reads of bytes from the input buffer. These
* require that you are using an architecture that uses PNG byte ordering
* (MSB first) and supports unaligned data storage. I think that PowerPC
* in big-endian mode and 680x0 are the only ones that will support this.
* The x86 line of processors definitely do not. The png_get_int_32()
* routine also assumes we are using two's complement format for negative
* values, which is almost certainly true.
*/
#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
#if defined(PNG_READ_pCAL_SUPPORTED)
#define png_get_int_32(buf) ( *((png_int_32p) (buf)))
#endif /* PNG_READ_pCAL_SUPPORTED */
#define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
#define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
#else
#if defined(PNG_READ_pCAL_SUPPORTED)
PNG_EXTERN png_int_32 png_get_int_32 PNGARG((png_bytep buf));
#endif /* PNG_READ_pCAL_SUPPORTED */
PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf));
PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf));
#endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
/* Initialize png_ptr struct for reading, and allocate any other memory.
* (old interface - NOT DLL EXPORTED).
*/
extern void png_read_init PNGARG((png_structp png_ptr));
/* Initialize png_ptr struct for writing, and allocate any other memory.
* (old interface - NOT DLL EXPORTED).
*/
extern void png_write_init PNGARG((png_structp png_ptr));
/* allocate memory for an internal libpng struct */
PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
/* free memory from internal libpng struct */
PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
malloc_fn));
PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
png_free_ptr free_fn));
/* free any memory that info_ptr points to and reset struct. */
PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* Function to allocate memory for zlib. */
PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
/* function to free memory for zlib */
PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
/* reset the CRC variable */
PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
/* Write the "data" buffer to whatever output you are using. */
PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
png_size_t length));
/* Read data from whatever input you are using into the "data" buffer */
PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
png_size_t length));
/* read bytes into buf, and update png_ptr->crc */
PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
png_size_t length));
/* read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
/* read the CRC from the file and compare it to the libpng calculated CRC */
PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
/* Calculate the CRC over a section of data. Note that we are only
* passing a maximum of 64K on systems that have this as a memory limit,
* since this is the maximum buffer size we can specify.
*/
PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
png_size_t length));
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
#endif
/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
* The only currently known PNG chunks that use signed numbers are
* the ancillary extension chunks, oFFs and pCAL.
*/
PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i));
#if defined(PNG_WRITE_pCAL_SUPPORTED)
PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
#endif
/* Place a 16 bit number into a buffer in PNG byte order.
* The parameter is declared unsigned int, not png_uint_16,
* just to avoid potential problems on pre-ANSI C compilers.
*/
PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i));
/* simple function to write the signature */
PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
/* write various chunks */
/* Write the IHDR chunk, and update the png_struct with the necessary
* information.
*/
PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
png_uint_32 height,
int bit_depth, int color_type, int compression_type, int filter_type,
int interlace_type));
PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_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));
#if defined(PNG_WRITE_gAMA_SUPPORTED)
PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
#endif
#if defined(PNG_WRITE_sBIT_SUPPORTED)
PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
int color_type));
#endif
#if defined(PNG_WRITE_cHRM_SUPPORTED)
PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
double white_x, double white_y,
double red_x, double red_y, double green_x, double green_y,
double blue_x, double blue_y));
#endif
#if defined(PNG_WRITE_sRGB_SUPPORTED)
PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
int intent));
#endif
#if defined(PNG_WRITE_tRNS_SUPPORTED)
PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
png_color_16p values, int number, int color_type));
#endif
#if defined(PNG_WRITE_bKGD_SUPPORTED)
PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
png_color_16p values, int color_type));
#endif
#if defined(PNG_WRITE_hIST_SUPPORTED)
PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
int num_hist));
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED) || \
defined(PNG_WRITE_pCAL_SUPPORTED)
PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
png_charp key, png_charpp new_key));
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED)
PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
png_charp text, png_size_t text_len));
#endif
#if defined(PNG_WRITE_zTXt_SUPPORTED)
PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
png_charp text, png_size_t text_len, int compression));
#endif
#if defined(PNG_WRITE_oFFs_SUPPORTED)
PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
png_uint_32 x_offset, png_uint_32 y_offset, int unit_type));
#endif
#if defined(PNG_WRITE_pCAL_SUPPORTED)
PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
png_int_32 X0, png_int_32 X1, int type, int nparams,
png_charp units, png_charpp params));
#endif
#if defined(PNG_WRITE_pHYs_SUPPORTED)
PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
int unit_type));
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
png_timep mod_time));
#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));
#if defined(PNG_READ_GAMMA_SUPPORTED)
PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
#endif
/* combine a row of data, dealing with alpha, etc. if requested */
PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
int mask));
#if defined(PNG_READ_INTERLACING_SUPPORTED)
/* expand an interlaced row */
PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
png_bytep row, int pass, png_uint_32 transformations));
#endif
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* grab pixels out of a row for an interlaced pass */
PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
png_bytep row, int pass));
#endif
/* unfilter a row */
PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
/* 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));
/* Write out the filtered row. */
PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
png_bytep filtered_row));
/* finish a row while reading, dealing with interlacing passes, etc. */
PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
/* initialize the row buffers, etc. */
PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
/* optional call to update the users info structure */
PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
png_infop info_ptr));
/* these are the functions that do the transformations */
#if defined(PNG_READ_FILLER_SUPPORTED)
PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
png_bytep row, png_uint_32 filler, png_uint_32 flags));
#endif
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
png_bytep row, png_uint_32 flags));
#endif
#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
#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
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
row_info, png_bytep row));
#endif
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
png_bytep row));
#endif
#if defined(PNG_READ_PACK_SUPPORTED)
PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
#endif
#if defined(PNG_READ_SHIFT_SUPPORTED)
PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
png_color_8p sig_bits));
#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
#if defined(PNG_READ_16_TO_8_SUPPORTED)
PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
#endif
#if defined(PNG_READ_DITHER_SUPPORTED)
PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
# if defined(PNG_CORRECT_PALETTE_SUPPORTED)
PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
png_colorp palette, int num_palette));
# endif
#endif
#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
#if defined(PNG_WRITE_PACK_SUPPORTED)
PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
png_bytep row, png_uint_32 bit_depth));
#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
png_color_8p bit_depth));
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
png_color_16p trans_values, png_color_16p background,
png_color_16p background_1,
png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
png_uint_16pp gamma_16_to_1, int gamma_shift));
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED)
PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
png_bytep gamma_table, png_uint_16pp gamma_16_table,
int gamma_shift));
#endif
#if defined(PNG_READ_EXPAND_SUPPORTED)
PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
png_bytep row, png_color_16p trans_value));
#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));
#if defined(PNG_READ_gAMA_SUPPORTED)
PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_bKGD_SUPPORTED)
PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
png_uint_32 length));
#endif
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_bytep chunk_name));
/* handle the transformations for reading and writing */
PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
png_uint_32 length));
PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
png_bytep buffer, png_size_t length));
PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
png_bytep buffer, png_size_t buffer_length));
PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
png_bytep buffer, png_size_t buffer_length));
PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 length));
PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
png_infop info_ptr));
PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
#if defined(PNG_READ_tEXt_SUPPORTED)
PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 length));
PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
png_infop info_ptr));
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 length));
PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
png_infop info_ptr));
#endif
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
#endif /* PNG_INTERNAL */
#ifdef __cplusplus
}
#endif
/* do not put anything past this line */
#endif /* _PNG_H */