* *       Glenn Randers-Pehrson *       libpng maintainer *       PNG Development Group */#ifndef PNG_H#define PNG_H/* This is not the place to learn how to use libpng.  The file libpng.txt * 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. *//* Version information for png.h - this should match the version in png.c */#define PNG_LIBPNG_VER_STRING "1.2.8"#define PNG_HEADER_VERSION_STRING \   " libpng version 1.2.8 - December 3, 2004 (header)\n"#define PNG_LIBPNG_VER_SONUM   0#define PNG_LIBPNG_VER_DLLNUM  13/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */#define PNG_LIBPNG_VER_MAJOR   1#define PNG_LIBPNG_VER_MINOR   2#define PNG_LIBPNG_VER_RELEASE 8/* This should match the numeric part of the final component of * PNG_LIBPNG_VER_STRING, omitting any leading zero: */#define PNG_LIBPNG_VER_BUILD  0/* Release Status */#define PNG_LIBPNG_BUILD_ALPHA    1#define PNG_LIBPNG_BUILD_BETA     2#define PNG_LIBPNG_BUILD_RC       3#define PNG_LIBPNG_BUILD_STABLE   4#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7  /* Release-Specific Flags */#define PNG_LIBPNG_BUILD_PATCH    8 /* Can be OR'ed with                                       PNG_LIBPNG_BUILD_STABLE only */#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with                                       PNG_LIBPNG_BUILD_SPECIAL */#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with                                       PNG_LIBPNG_BUILD_PRIVATE */#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE/* Careful here.  At one time, Guy wanted to use 082, but that would be octal. * We must not include leading zeros. * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only * version 1.0.0 was mis-numbered 100 instead of 10000).  From * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release */#define PNG_LIBPNG_VER 10208 /* 1.2.8 */#ifndef PNG_VERSION_INFO_ONLY/* include the compression library's header */#include "zlib.h"#endif/* include all user configurable info, including optional assembler routines */#include "pngconf.h"/* * Added at libpng-1.2.8 *//* Ref MSDN: Private as priority over Special * VS_FF_PRIVATEBUILD File *was not* built using standard release * procedures. If this value is given, the StringFileInfo block must * contain a PrivateBuild string.  * * VS_FF_SPECIALBUILD File *was* built by the original company using * standard release procedures but is a variation of the standard * file of the same version number. If this value is given, the * StringFileInfo block must contain a SpecialBuild string.  */#if defined(PNG_USER_PRIVATEBUILD)#  define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE | \          PNG_LIBPNG_BUILD_PRIVATE#else#  if defined(PNG_LIBPNG_SPECIALBUILD)#    define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE | \            PNG_LIBPNG_BUILD_SPECIAL#  else#    define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE#  endif#endif#ifndef PNG_VERSION_INFO_ONLY/* Inhibit C++ name-mangling for libpng functions but not for system calls. */#ifdef __cplusplusextern "C" {#endif /* __cplusplus *//* This file is arranged in several sections.  The first section contains * structure and type definitions.  The second section contains the external * library functions, while the third has the internal library functions, * which applications aren't expected to use directly. */#ifndef PNG_NO_TYPECAST_NULL#define int_p_NULL                (int *)NULL#define png_bytep_NULL            (png_bytep)NULL#define png_bytepp_NULL           (png_bytepp)NULL#define png_doublep_NULL          (png_doublep)NULL#define png_error_ptr_NULL        (png_error_ptr)NULL#define png_flush_ptr_NULL        (png_flush_ptr)NULL#define png_free_ptr_NULL         (png_free_ptr)NULL#define png_infopp_NULL           (png_infopp)NULL#define png_malloc_ptr_NULL       (png_malloc_ptr)NULL#define png_read_status_ptr_NULL  (png_read_status_ptr)NULL#define png_rw_ptr_NULL           (png_rw_ptr)NULL#define png_structp_NULL          (png_structp)NULL#define png_uint_16p_NULL         (png_uint_16p)NULL#define png_voidp_NULL            (png_voidp)NULL#define png_write_status_ptr_NULL (png_write_status_ptr)NULL#else#define int_p_NULL                NULL#define png_bytep_NULL            NULL#define png_bytepp_NULL           NULL#define png_doublep_NULL          NULL#define png_error_ptr_NULL        NULL#define png_flush_ptr_NULL        NULL#define png_free_ptr_NULL         NULL#define png_infopp_NULL           NULL#define png_malloc_ptr_NULL       NULL#define png_read_status_ptr_NULL  NULL#define png_rw_ptr_NULL           NULL#define png_structp_NULL          NULL#define png_uint_16p_NULL         NULL#define png_voidp_NULL            NULL#define png_write_status_ptr_NULL NULL#endif/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)/* Version information for C files, stored in png.c.  This had better match * the version above. */#ifdef PNG_USE_GLOBAL_ARRAYSPNG_EXPORT_VAR (const char) png_libpng_ver[18];  /* need room for 99.99.99beta99z */#else#define png_libpng_ver png_get_header_ver(NULL)#endif#ifdef PNG_USE_GLOBAL_ARRAYS/* This was removed in version 1.0.5c *//* Structures to facilitate easy interlacing.  See png.c for more details */PNG_EXPORT_VAR (const int FARDATA) png_pass_start[7];PNG_EXPORT_VAR (const int FARDATA) png_pass_inc[7];PNG_EXPORT_VAR (const int FARDATA) png_pass_ystart[7];PNG_EXPORT_VAR (const int FARDATA) png_pass_yinc[7];PNG_EXPORT_VAR (const int FARDATA) png_pass_mask[7];PNG_EXPORT_VAR (const int FARDATA) png_pass_dsp_mask[7];#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROWPNG_EXPORT_VAR (const int FARDATA) png_pass_width[7];#endif/* This isn't currently used.  If you need it, see png.c for more details.PNG_EXPORT_VAR (const int FARDATA) png_pass_height[7];*/#endif#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;/* * The following two structures are used for the in-core representation * of sPLT chunks. */typedef struct png_sPLT_entry_struct{   png_uint_16 red;   png_uint_16 green;   png_uint_16 blue;   png_uint_16 alpha;   png_uint_16 frequency;} png_sPLT_entry;typedef png_sPLT_entry FAR * png_sPLT_entryp;typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;/*  When the depth of the sPLT palette is 8 bits, the color and alpha samples *  occupy the LSB of their respective members, and the MSB of each member *  is zero-filled.  The frequency member always occupies the full 16 bits. */typedef struct png_sPLT_struct{   png_charp name;           /* palette name */   png_byte depth;           /* depth of palette samples */   png_sPLT_entryp entries;  /* palette entries */   png_int_32 nentries;      /* number of palette entries */} png_sPLT_t;typedef png_sPLT_t FAR * png_sPLT_tp;typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;#ifdef PNG_TEXT_SUPPORTED/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, * and whether that contents is compressed or not.  The "key" field * points to a regular zero-terminated C string.  The "text", "lang", and * "lang_key" fields can be regular C strings, empty strings, or NULL pointers. * However, the * structure returned by png_get_text() will always contain * regular zero-terminated C strings (possibly empty), never NULL pointers, * so they can be safely used in printf() and other string-handling functions. */typedef struct png_text_struct{   int  compression;       /* compression value:                             -1: tEXt, none                              0: zTXt, deflate                              1: iTXt, none                              2: iTXt, deflate  */   png_charp key;          /* keyword, 1-79 character description of "text" */   png_charp text;         /* comment, may be an empty string (ie "")                              or a NULL pointer */   png_size_t text_length; /* length of the text string */#ifdef PNG_iTXt_SUPPORTED   png_size_t itxt_length; /* length of the itxt string */   png_charp lang;         /* language code, 0-79 characters                              or a NULL pointer */   png_charp lang_key;     /* keyword translated UTF-8 string, 0 or more                              chars or a NULL pointer */#endif} png_text;typedef png_text FAR * png_textp;typedef png_text FAR * FAR * png_textpp;#endif/* 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_ITXT_COMPRESSION_NONE     1#define PNG_ITXT_COMPRESSION_zTXt     2#define PNG_TEXT_COMPRESSION_LAST     3  /* Not a valid value *//* png_time is a way to hold the time in an machine independent way. * Two conversions are provided, both from time_t and struct tm.  There * is no portable way to convert to either of these structures, as far * as I know.  If you know of a portable way, send it to me.  As a side * note - PNG has always been Year 2000 compliant! */typedef struct png_time_struct{   png_uint_16 year; /* full year, as in, 1995 */   png_byte month;   /* month of year, 1 - 12 */   png_byte day;     /* day of month, 1 - 31 */   png_byte hour;    /* hour of day, 0 - 23 */   png_byte minute;  /* minute of hour, 0 - 59 */   png_byte second;  /* second of minute, 0 - 60 (for leap seconds) */} png_time;typedef png_time FAR * png_timep;typedef png_time FAR * FAR * png_timepp;#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)/* png_unknown_chunk is a structure to hold queued chunks for which there is * no specific support.  The idea is that we can use this to queue * up private chunks for output even though the library doesn't actually * know about their semantics. */typedef struct png_unknown_chunk_t{