/* png.h - header file for PNG reference library
*
- * libpng 1.0.1
- * For conditions of distribution and use, see the COPYRIGHT NOTICE below.
+ * 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 Glenn Randers-Pehrson
- * March 15, 1998
+ * 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:
*
* 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
+ * 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).
- *
+ * 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 for more information. The PNG specification is available
- * as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/>
+ * See libpng.txt or libpng.3 for more information. The PNG specification
+ * is available as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/>
* and as a W3C Recommendation <http://www.w3.org/TR/REC.png.html>
*
* Contributing Authors:
* appreciated.
*/
+
#ifndef _PNG_H
#define _PNG_H
*/
/* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.0.1"
+#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 10001 /* 1.0.1 */
+#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)
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
* 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 which abstract the contents of
+ * 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
/* 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 which describes the textual data contained
+ * 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_tEXt/zTXt_SUPPORTED || PNG_WRITE_tEXt/zTXt_SUPPORTED */
+#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_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)
+#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 which should be treated as fully transparent.
+ * 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 */
#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
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 the functions which
- * modify the default I/O functions to user I/O functions. 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.
+/* 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;
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.
png_byte sig_bytes; /* magic bytes read/written from start of file */
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
- png_byte filler; /* filler byte for 24->32-bit pixel expansion */
+ 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;
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)
+#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 */
#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)
+#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_tRNS_SUPPORTED || PNG_READ_BACKGROUND_SUPPORTED */
+#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
#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;
/* 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, voidp error_ptr,
+ 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 reading, and any other memory */
+/* 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, voidp error_ptr,
+ 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));
#endif /* PNG_READ_GRAY_TO_RGB_SUPPORTED */
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-/* Reduce RGB to grayscale. (Not yet implemented) */
-extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr));
+/* 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,
* 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));
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));
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 which combines rows. Not very much different than the
+/* 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,
/* 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));
-#ifdef PNGTEST_MEMORY_DEBUG
-/* debugging versions of png_malloc() and png_free() */
-extern PNG_EXPORT(png_voidp,png_debug_malloc) PNGARG((png_structp png_ptr,
- png_uint_32 size));
-extern PNG_EXPORT(void,png_debug_free) PNGARG((png_structp png_ptr,
- png_voidp ptr));
-#endif
#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));
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));
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_tEXt_SUPPORTED || PNG_WRITE_tEXt_SUPPORTED ||
- PNG_READ_zTXt_SUPPORTED || PNG_WRITE_zTXt_SUPPORTED */
+#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,
* 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)
-#ifdef PNG_NO_STDIO
-#include <stdio.h>
-#endif
#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==3 ? "\t\t\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==3 ? "\t\t\t":""))),p1)
+ (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==3 ? "\t\t\t":""))),p1,p2)
-#else
+ (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 /* (PNG_DEBUG > 0) */
+#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
#define PNG_DITHER 0x0040
#define PNG_BACKGROUND 0x0080
#define PNG_BACKGROUND_EXPAND 0x0100
-#define PNG_RGB_TO_GRAY 0x0200 /* Not currently implemented */
+ /* 0x0200 unused */
#define PNG_16_TO_8 0x0400
#define PNG_RGBA 0x0800
#define PNG_EXPAND 0x1000
#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_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)
#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_BIG_ENDIAN_GET_SUPPORTED */
+#endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
/* Initialize png_ptr struct for reading, and allocate any other memory.
* (old interface - NOT DLL EXPORTED).
/* 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));
#endif
/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
- * The only currently known PNG chunk that uses signed numbers is
- * the ancillary extension chunk, pCAL.
+ * 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));
int num_hist));
#endif
-#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
+#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
#endif
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-PNG_EXTERN void png_do_rgb_to_gray PNGARG((png_row_infop row_info,
- png_bytep row));
+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)