pngtrans.c

/* pngtrans.c - transforms the data in a row (used by both readers and writers)
 *
 * Last changed in libpng 1.2.41 [December 3, 2009]
 * Copyright (c) 1998-2009 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
 */

#define PNG_INTERNAL
#define PNG_NO_PEDANTIC_WARNINGS
#include "png.h"
#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)

#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* Turn on BGR-to-RGB mapping */
void PNGAPI
png_set_bgr(png_structp png_ptr)
{
   png_debug(1, "in png_set_bgr");

   if (png_ptr == NULL)
      return;
   png_ptr->transformations |= PNG_BGR;
}
#endif

#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* Turn on 16 bit byte swapping */
void PNGAPI
png_set_swap(png_structp png_ptr)
{
   png_debug(1, "in png_set_swap");

   if (png_ptr == NULL)
      return;
   if (png_ptr->bit_depth == 16)
      png_ptr->transformations |= PNG_SWAP_BYTES;
}
#endif

#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
/* Turn on pixel packing */
void PNGAPI
png_set_packing(png_structp png_ptr)
{
   png_debug(1, "in png_set_packing");

   if (png_ptr == NULL)
      return;
   if (png_ptr->bit_depth < 8)
   {
      png_ptr->transformations |= PNG_PACK;
      png_ptr->usr_bit_depth = 8;
   }
}
#endif

#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
/* Turn on packed pixel swapping */
void PNGAPI
png_set_packswap(png_structp png_ptr)
{
   png_debug(1, "in png_set_packswap");

   if (png_ptr == NULL)