/* pngpriv.h - private declarations for use inside libpng

 *

 * libpng version 1.4.0 - January 3, 2010

 * For conditions of distribution and use, see copyright notice in png.h

 * Copyright (c) 1998-2010 Glenn Randers-Pehrson

 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)

 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)

 *

 * This code is released under the libpng license.

 * For conditions of distribution and use, see the disclaimer

 * and license in png.h

 */

/* The symbols declared in this file (including the functions declared

 * as PNG_EXTERN) are PRIVATE.  They are not part of the libpng public

 * interface, and are not recommended for use by regular applications.

 * Some of them may become public in the future; others may stay private,

 * change in an incompatible way, or even disappear.

 * Although the libpng users are not forbidden to include this header,

 * they should be well aware of the issues that may arise from doing so.

 */

#ifndef PNGPRIV_H

#define PNGPRIV_H

#ifndef PNG_VERSION_INFO_ONLY

#include <stdlib.h>

/* The functions exported by PNG_EXTERN are internal functions, which

 * aren't usually used outside the library (as far as I know), so it is

 * debatable if they should be exported at all.  In the future, when it

 * is possible to have run-time registry of chunk-handling functions,

 * some of these will be made available again.

#define PNG_EXTERN extern

 */

#define PNG_EXTERN

/* Other defines specific to compilers can go here.  Try to keep

 * them inside an appropriate ifdef/endif pair for portability.

 */

#ifdef PNG_FLOATING_POINT_SUPPORTED

#  ifdef MACOS

     /* We need to check that <math.h> hasn't already been included earlier

      * as it seems it doesn't agree with <fp.h>, yet we should really use

      * <fp.h> if possible.

      */

#    if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)

#      include <fp.h>

#    endif

#  else

#    include <math.h>

#  endif

#  if defined(_AMIGA) && defined(__SASC) && defined(_M68881)

     /* Amiga SAS/C: We must include builtin FPU functions when compiling using

      * MATH=68881

      */

#    include <m68881.h>

#  endif

#endif

/* Codewarrior on NT has linking problems without this. */

#if (defined(__MWERKS__) && defined(WIN32)) || defined(__STDC__)

#  define PNG_ALWAYS_EXTERN

#endif

/* This provides the non-ANSI (far) memory allocation routines. */

#if defined(__TURBOC__) && defined(__MSDOS__)

#  include <mem.h>

#  include <alloc.h>

#endif

#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \

    defined(_WIN32) || defined(__WIN32__)

#  if !defined(__SYMBIAN32__)

#    include <windows.h>  /* defines _WINDOWS_ macro */

#  endif

/* I have no idea why is this necessary... */

#  ifdef _MSC_VER

#    include <malloc.h>

#  endif

#endif

/* Various modes of operation.  Note that after an init, mode is set to

 * zero automatically when the structure is created.

 */

#define PNG_HAVE_IHDR               0x01

#define PNG_HAVE_PLTE               0x02

#define PNG_HAVE_IDAT               0x04

#define PNG_AFTER_IDAT              0x08 /* Have complete zlib datastream */

#define PNG_HAVE_IEND               0x10

#define PNG_HAVE_gAMA               0x20

#define PNG_HAVE_cHRM               0x40

#define PNG_HAVE_sRGB               0x80

#define PNG_HAVE_CHUNK_HEADER      0x100

#define PNG_WROTE_tIME             0x200

#define PNG_WROTE_INFO_BEFORE_PLTE 0x400

#define PNG_BACKGROUND_IS_GRAY     0x800

#define PNG_HAVE_PNG_SIGNATURE    0x1000

#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */

/* 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              0x8000L

#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 */

                       /*     0x800000L     Unused */

#define PNG_ADD_ALPHA         0x1000000L  /* Added to libpng-1.2.7 */

#define PNG_EXPAND_tRNS       0x2000000L  /* Added to libpng-1.2.9 */

                       /*   0x4000000L  unused */

                       /*   0x8000000L  unused */

                       /*  0x10000000L  unused */

                       /*  0x20000000L  unused */

                       /*  0x40000000L  unused */

/* 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

                                /*        0x1000  unused */

                                /*        0x2000  unused */

                                /*        0x4000  unused */

#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS      0x8000L

#define PNG_FLAG_KEEP_UNSAFE_CHUNKS       0x10000L

#define PNG_FLAG_LIBRARY_MISMATCH         0x20000L

#define PNG_FLAG_STRIP_ERROR_NUMBERS      0x40000L

#define PNG_FLAG_STRIP_ERROR_TEXT         0x80000L

#define PNG_FLAG_MALLOC_NULL_MEM_OK       0x100000L

#define PNG_FLAG_ADD_ALPHA                0x200000L  /* Added to libpng-1.2.8 */

#define PNG_FLAG_STRIP_ALPHA              0x400000L  /* Added to libpng-1.2.8 */

#define PNG_FLAG_BENIGN_ERRORS_WARN       0x800000L  /* Added to libpng-1.4.0 */

                                  /*     0x1000000L  unused */

                                  /*     0x2000000L  unused */

                                  /*     0x4000000L  unused */

                                  /*     0x8000000L  unused */

                                  /*    0x10000000L  unused */

                                  /*    0x20000000L  unused */

                                  /*    0x40000000L  unused */

#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \

                                     PNG_FLAG_CRC_ANCILLARY_NOWARN)

#define PNG_FLAG_CRC_CRITICAL_MASK  (PNG_FLAG_CRC_CRITICAL_USE | \

                                     PNG_FLAG_CRC_CRITICAL_IGNORE)

#define PNG_FLAG_CRC_MASK           (PNG_FLAG_CRC_ANCILLARY_MASK | \

                                     PNG_FLAG_CRC_CRITICAL_MASK)

/* Save typing and make code easier to understand */

#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \

   abs((int)((c1).green) - (int)((c2).green)) + \

   abs((int)((c1).blue) - (int)((c2).blue)))

/* Added to libpng-1.2.6 JB */

#define PNG_ROWBYTES(pixel_bits, width) \

    ((pixel_bits) >= 8 ? \

    ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \

    (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )

/* PNG_OUT_OF_RANGE returns true if value is outside the range

 * ideal-delta..ideal+delta.  Each argument is evaluated twice.

 * "ideal" and "delta" should be constants, normally simple

 * integers, "value" a variable. Added to libpng-1.2.6 JB

 */

#define PNG_OUT_OF_RANGE(value, ideal, delta) \

        ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )

/* Constant strings for known chunk types.  If you need to add a chunk,

 * define the name here, and add an invocation of the macro wherever it's

 * needed.

 */

#define PNG_IHDR PNG_CONST png_byte png_IHDR[5] = { 73,  72,  68,  82, '\0'}

#define PNG_IDAT PNG_CONST png_byte png_IDAT[5] = { 73,  68,  65,  84, '\0'}

#define PNG_IEND PNG_CONST png_byte png_IEND[5] = { 73,  69,  78,  68, '\0'}

#define PNG_PLTE PNG_CONST png_byte png_PLTE[5] = { 80,  76,  84,  69, '\0'}

#define PNG_bKGD PNG_CONST png_byte png_bKGD[5] = { 98,  75,  71,  68, '\0'}

#define PNG_cHRM PNG_CONST png_byte png_cHRM[5] = { 99,  72,  82,  77, '\0'}

#define PNG_gAMA PNG_CONST png_byte png_gAMA[5] = {103,  65,  77,  65, '\0'}

#define PNG_hIST PNG_CONST png_byte png_hIST[5] = {104,  73,  83,  84, '\0'}

#define PNG_iCCP PNG_CONST png_byte png_iCCP[5] = {105,  67,  67,  80, '\0'}

#define PNG_iTXt PNG_CONST png_byte png_iTXt[5] = {105,  84,  88, 116, '\0'}

#define PNG_oFFs PNG_CONST png_byte png_oFFs[5] = {111,  70,  70, 115, '\0'}

#define PNG_pCAL PNG_CONST png_byte png_pCAL[5] = {112,  67,  65,  76, '\0'}

#define PNG_sCAL PNG_CONST png_byte png_sCAL[5] = {115,  67,  65,  76, '\0'}

#define PNG_pHYs PNG_CONST png_byte png_pHYs[5] = {112,  72,  89, 115, '\0'}

#define PNG_sBIT PNG_CONST png_byte png_sBIT[5] = {115,  66,  73,  84, '\0'}

#define PNG_sPLT PNG_CONST png_byte png_sPLT[5] = {115,  80,  76,  84, '\0'}

#define PNG_sRGB PNG_CONST png_byte png_sRGB[5] = {115,  82,  71,  66, '\0'}

#define PNG_sTER PNG_CONST png_byte png_sTER[5] = {115,  84,  69,  82, '\0'}

#define PNG_tEXt PNG_CONST png_byte png_tEXt[5] = {116,  69,  88, 116, '\0'}

#define PNG_tIME PNG_CONST png_byte png_tIME[5] = {116,  73,  77,  69, '\0'}

#define PNG_tRNS PNG_CONST png_byte png_tRNS[5] = {116,  82,  78,  83, '\0'}

#define PNG_zTXt PNG_CONST png_byte png_zTXt[5] = {122,  84,  88, 116, '\0'}

/* Inhibit C++ name-mangling for libpng functions but not for system calls. */

#ifdef __cplusplus

extern "C" {

#endif /* __cplusplus */

/* These functions are used internally in the code.  They generally

 * shouldn't be used unless you are writing code to add or replace some

 * functionality in libpng.  More information about most functions can

 * be found in the files where the functions are located.

 */

/* 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_voidp mem_ptr));

PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,

   png_free_ptr free_fn, png_voidp mem_ptr));

/* Free any memory that info_ptr points to and reset struct. */

PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,

   png_infop info_ptr));

/* Function to allocate memory for zlib.  PNGAPI is disallowed. */

PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));

/* Function to free memory for zlib.  PNGAPI is disallowed. */

PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));

/* Next four functions are used internally as callbacks.  PNGAPI is required

 * but not PNG_EXPORT.  PNGAPI added at libpng version 1.2.3. */

PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,

   png_bytep data, png_size_t length));

#ifdef PNG_PROGRESSIVE_READ_SUPPORTED

PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,

   png_bytep buffer, png_size_t length));

#endif

PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,

   png_bytep data, png_size_t length));

#ifdef PNG_WRITE_FLUSH_SUPPORTED

#ifdef PNG_STDIO_SUPPORTED

PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));

#endif

#endif

/* Reset the CRC variable */

PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));

/* Write the "data" buffer to whatever output you are using */

PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,

   png_size_t length));

/* Read the chunk header (length + type name) */

PNG_EXTERN png_uint_32 png_read_chunk_header PNGARG((png_structp png_ptr));

/* Read data from whatever input you are using into the "data" buffer */

PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,

   png_size_t length));

/* Read bytes into buf, and update png_ptr->crc */

PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,

   png_size_t length));

/* Decompress data in a chunk that uses compression */

#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \

    defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)

PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,

   int comp_type, png_size_t chunklength, png_size_t prefix_length,

   png_size_t *data_length));

#endif

/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */

PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));

/* Read the CRC from the file and compare it to the libpng calculated CRC */

PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));

/* Calculate the CRC over a section of data.  Note that we are only

 * passing a maximum of 64K on systems that have this as a memory limit,

 * since this is the maximum buffer size we can specify.

 */

PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,

   png_size_t length));

#ifdef PNG_WRITE_FLUSH_SUPPORTED

PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));

#endif

/* Write various chunks */

/* Write the IHDR chunk, and update the png_struct with the necessary

 * information.

 */

PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,

   png_uint_32 height,

   int bit_depth, int color_type, int compression_method, int filter_method,

   int interlace_method));

PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,

   png_uint_32 num_pal));

PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,

   png_size_t length));

PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));

#ifdef PNG_WRITE_gAMA_SUPPORTED

#ifdef PNG_FLOATING_POINT_SUPPORTED

PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));

#endif

#ifdef PNG_FIXED_POINT_SUPPORTED

PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point

    file_gamma));

#endif

#endif

#ifdef PNG_WRITE_sBIT_SUPPORTED

PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,

   int color_type));

#endif

#ifdef PNG_WRITE_cHRM_SUPPORTED

#ifdef PNG_FLOATING_POINT_SUPPORTED

PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,

   double white_x, double white_y,

   double red_x, double red_y, double green_x, double green_y,

   double blue_x, double blue_y));

#endif

PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,

   png_fixed_point int_white_x, png_fixed_point int_white_y,

   png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point

   int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,

   png_fixed_point int_blue_y));

#endif

#ifdef PNG_WRITE_sRGB_SUPPORTED

PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,

   int intent));

#endif

#ifdef PNG_WRITE_iCCP_SUPPORTED

PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,

   png_charp name, int compression_type,

   png_charp profile, int proflen));

   /* Note to maintainer: profile should be png_bytep */

#endif

#ifdef PNG_WRITE_sPLT_SUPPORTED

PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,

   png_sPLT_tp palette));

#endif

#ifdef 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

#ifdef PNG_WRITE_bKGD_SUPPORTED

PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,

   png_color_16p values, int color_type));

#endif

#ifdef 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_pCAL_SUPPORTED) || \

    defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)

PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,

   png_charp key, png_charpp new_key));

#endif

#ifdef 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

#ifdef 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

#ifdef PNG_WRITE_iTXt_SUPPORTED

PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,

   int compression, png_charp key, png_charp lang, png_charp lang_key,

   png_charp text));

#endif

#ifdef PNG_TEXT_SUPPORTED  /* Added at version 1.0.14 and 1.2.4 */

PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,

   png_infop info_ptr, png_textp text_ptr, int num_text));

#endif

#ifdef PNG_WRITE_oFFs_SUPPORTED

PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,

   png_int_32 x_offset, png_int_32 y_offset, int unit_type));

#endif

#ifdef PNG_WRITE_pCAL_SUPPORTED

PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,

   png_int_32 X0, png_int_32 X1, int type, int nparams,

   png_charp units, png_charpp params));

#endif

#ifdef PNG_WRITE_pHYs_SUPPORTED

PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,

   png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,

   int unit_type));

#endif

#ifdef PNG_WRITE_tIME_SUPPORTED

PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,

   png_timep mod_time));

#endif

#ifdef PNG_WRITE_sCAL_SUPPORTED

#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_STDIO_SUPPORTED)

PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,

   int unit, double width, double height));

#else

#ifdef PNG_FIXED_POINT_SUPPORTED

PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,

   int unit, png_charp width, png_charp height));

#endif

#endif

#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));

#ifdef PNG_READ_GAMMA_SUPPORTED

PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr,

   png_byte bit_depth));

#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));

#ifdef PNG_READ_INTERLACING_SUPPORTED

/* Expand an interlaced row */

/* OLD pre-1.0.9 interface:

PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,

   png_bytep row, int pass, png_uint_32 transformations));

 */

PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));

#endif

/* GRR TO DO (2.0 or whenever):  simplify other internal calling interfaces */

#ifdef PNG_WRITE_INTERLACING_SUPPORTED

/* Grab pixels out of a row for an interlaced pass */

PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,

   png_bytep row, int pass));

#endif

/* Unfilter a row */

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 */

#ifdef PNG_READ_FILLER_SUPPORTED

PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,

   png_bytep row, png_uint_32 filler, png_uint_32 flags));