text: 
  /* pngset.c - storage of image information into info struct
   *
   * Last changed in libpng 1.2.22 [November 6, 2007]
   * For conditions of distribution and use, see copyright notice in png.h
   * Copyright (c) 1998-2007 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.)
   *
   * The functions here are used during reads to store data from the file
   * into the info struct, and during writes to store application data
   * into the info struct for writing into the file.  This abstracts the
   * info struct and allows us to change the structure in the future.
   */
  
  #define PNG_INTERNAL
  #include "png.h"
  
  #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
  
  #if defined(PNG_bKGD_SUPPORTED)
  void PNGAPI
  png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
  {
     png_debug1(1, "in %s storage function\n", "bKGD");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     png_memcpy(&(info_ptr->background), background, png_sizeof(png_color_16));
     info_ptr->valid |= PNG_INFO_bKGD;
  }
  #endif
  
  #if defined(PNG_cHRM_SUPPORTED)
  #ifdef PNG_FLOATING_POINT_SUPPORTED
  void PNGAPI
  png_set_cHRM(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)
  {
     png_debug1(1, "in %s storage function\n", "cHRM");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
     if (!(white_x || white_y || red_x || red_y || green_x || green_y ||
         blue_x || blue_y))
     {
        png_warning(png_ptr,
          "Ignoring attempt to set all-zero chromaticity values");
        return;
     }
     if (white_x < 0.0 || white_y < 0.0 ||
           red_x < 0.0 ||   red_y < 0.0 ||
         green_x < 0.0 || green_y < 0.0 ||
          blue_x < 0.0 ||  blue_y < 0.0)
     {
        png_warning(png_ptr,
          "Ignoring attempt to set negative chromaticity value");
        return;
     }
     if (white_x > 21474.83 || white_y > 21474.83 ||
           red_x > 21474.83 ||   red_y > 21474.83 ||
         green_x > 21474.83 || green_y > 21474.83 ||
          blue_x > 21474.83 ||  blue_y > 21474.83)
     {
        png_warning(png_ptr,
          "Ignoring attempt to set chromaticity value exceeding 21474.83");
        return;
     }
  
     info_ptr->x_white = (float)white_x;
     info_ptr->y_white = (float)white_y;
     info_ptr->x_red   = (float)red_x;
     info_ptr->y_red   = (float)red_y;
     info_ptr->x_green = (float)green_x;
     info_ptr->y_green = (float)green_y;
     info_ptr->x_blue  = (float)blue_x;
     info_ptr->y_blue  = (float)blue_y;
  #ifdef PNG_FIXED_POINT_SUPPORTED
     info_ptr->int_x_white = (png_fixed_point)(white_x*100000.+0.5);
     info_ptr->int_y_white = (png_fixed_point)(white_y*100000.+0.5);
     info_ptr->int_x_red   = (png_fixed_point)(  red_x*100000.+0.5);
     info_ptr->int_y_red   = (png_fixed_point)(  red_y*100000.+0.5);
     info_ptr->int_x_green = (png_fixed_point)(green_x*100000.+0.5);
     info_ptr->int_y_green = (png_fixed_point)(green_y*100000.+0.5);
     info_ptr->int_x_blue  = (png_fixed_point)( blue_x*100000.+0.5);
     info_ptr->int_y_blue  = (png_fixed_point)( blue_y*100000.+0.5);
  #endif
     info_ptr->valid |= PNG_INFO_cHRM;
  }
  #endif
  #ifdef PNG_FIXED_POINT_SUPPORTED
  void PNGAPI
  png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
     png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
     png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
     png_fixed_point blue_x, png_fixed_point blue_y)
  {
     png_debug1(1, "in %s storage function\n", "cHRM");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     if (!(white_x || white_y || red_x || red_y || green_x || green_y ||
         blue_x || blue_y))
     {
        png_warning(png_ptr,
          "Ignoring attempt to set all-zero chromaticity values");
        return;
     }
     if (white_x < 0 || white_y < 0 ||
           red_x < 0 ||   red_y < 0 ||
         green_x < 0 || green_y < 0 ||
          blue_x < 0 ||  blue_y < 0)
     {
        png_warning(png_ptr,
          "Ignoring attempt to set negative chromaticity value");
        return;
     }
  #ifdef PNG_FLOATING_POINT_SUPPORTED
     if (white_x > (double) PNG_UINT_31_MAX ||
         white_y > (double) PNG_UINT_31_MAX ||
           red_x > (double) PNG_UINT_31_MAX ||
           red_y > (double) PNG_UINT_31_MAX ||
         green_x > (double) PNG_UINT_31_MAX ||
         green_y > (double) PNG_UINT_31_MAX ||
          blue_x > (double) PNG_UINT_31_MAX ||
          blue_y > (double) PNG_UINT_31_MAX)
  #else
     if (white_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
         white_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
           red_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
           red_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
         green_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
         green_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
          blue_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
          blue_y > (png_fixed_point) PNG_UINT_31_MAX/100000L)
  #endif
     {
        png_warning(png_ptr,
          "Ignoring attempt to set chromaticity value exceeding 21474.83");
        return;
     }
     info_ptr->int_x_white = white_x;
     info_ptr->int_y_white = white_y;
     info_ptr->int_x_red   = red_x;
     info_ptr->int_y_red   = red_y;
     info_ptr->int_x_green = green_x;
     info_ptr->int_y_green = green_y;
     info_ptr->int_x_blue  = blue_x;
     info_ptr->int_y_blue  = blue_y;
  #ifdef PNG_FLOATING_POINT_SUPPORTED
     info_ptr->x_white = (float)(white_x/100000.);
     info_ptr->y_white = (float)(white_y/100000.);
     info_ptr->x_red   = (float)(  red_x/100000.);
     info_ptr->y_red   = (float)(  red_y/100000.);
     info_ptr->x_green = (float)(green_x/100000.);
     info_ptr->y_green = (float)(green_y/100000.);
     info_ptr->x_blue  = (float)( blue_x/100000.);
     info_ptr->y_blue  = (float)( blue_y/100000.);
  #endif
     info_ptr->valid |= PNG_INFO_cHRM;
  }
  #endif
  #endif
  
  #if defined(PNG_gAMA_SUPPORTED)
  #ifdef PNG_FLOATING_POINT_SUPPORTED
  void PNGAPI
  png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
  {
     double gamma;
     png_debug1(1, "in %s storage function\n", "gAMA");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     /* Check for overflow */
     if (file_gamma > 21474.83)
     {
        png_warning(png_ptr, "Limiting gamma to 21474.83");
        gamma=21474.83;
     }
     else
        gamma=file_gamma;
     info_ptr->gamma = (float)gamma;
  #ifdef PNG_FIXED_POINT_SUPPORTED
     info_ptr->int_gamma = (int)(gamma*100000.+.5);
  #endif
     info_ptr->valid |= PNG_INFO_gAMA;
     if(gamma == 0.0)
        png_warning(png_ptr, "Setting gamma=0");
  }
  #endif
  void PNGAPI
  png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
     int_gamma)
  {
     png_fixed_point gamma;
  
     png_debug1(1, "in %s storage function\n", "gAMA");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     if (int_gamma > (png_fixed_point) PNG_UINT_31_MAX)
     {
       png_warning(png_ptr, "Limiting gamma to 21474.83");
       gamma=PNG_UINT_31_MAX;
     }
     else
     {
       if (int_gamma < 0)
       {
         png_warning(png_ptr, "Setting negative gamma to zero");
         gamma=0;
       }
       else
         gamma=int_gamma;
     }
  #ifdef PNG_FLOATING_POINT_SUPPORTED
     info_ptr->gamma = (float)(gamma/100000.);
  #endif
  #ifdef PNG_FIXED_POINT_SUPPORTED
     info_ptr->int_gamma = gamma;
  #endif
     info_ptr->valid |= PNG_INFO_gAMA;
     if(gamma == 0)
        png_warning(png_ptr, "Setting gamma=0");
  }
  #endif
  
  #if defined(PNG_hIST_SUPPORTED)
  void PNGAPI
  png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
  {
     int i;
  
     png_debug1(1, "in %s storage function\n", "hIST");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
     if (info_ptr->num_palette == 0 || info_ptr->num_palette
         > PNG_MAX_PALETTE_LENGTH)
     {
         png_warning(png_ptr,
            "Invalid palette size, hIST allocation skipped.");
         return;
     }
  
  #ifdef PNG_FREE_ME_SUPPORTED
     png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
  #endif
     /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in version
        1.2.1 */
     png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr,
        (png_uint_32)(PNG_MAX_PALETTE_LENGTH * png_sizeof (png_uint_16)));
     if (png_ptr->hist == NULL)
       {
         png_warning(png_ptr, "Insufficient memory for hIST chunk data.");
         return;
       }
  
     for (i = 0; i < info_ptr->num_palette; i++)
         png_ptr->hist[i] = hist[i];
     info_ptr->hist = png_ptr->hist;
     info_ptr->valid |= PNG_INFO_hIST;
  
  #ifdef PNG_FREE_ME_SUPPORTED
     info_ptr->free_me |= PNG_FREE_HIST;
  #else
     png_ptr->flags |= PNG_FLAG_FREE_HIST;
  #endif
  }
  #endif
  
  void PNGAPI
  png_set_IHDR(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)
  {
     png_debug1(1, "in %s storage function\n", "IHDR");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     /* check for width and height valid values */
     if (width == 0 || height == 0)
        png_error(png_ptr, "Image width or height is zero in IHDR");
  #ifdef PNG_SET_USER_LIMITS_SUPPORTED
     if (width > png_ptr->user_width_max || height > png_ptr->user_height_max)
        png_error(png_ptr, "image size exceeds user limits in IHDR");
  #else
     if (width > PNG_USER_WIDTH_MAX || height > PNG_USER_HEIGHT_MAX)
        png_error(png_ptr, "image size exceeds user limits in IHDR");
  #endif
     if (width > PNG_UINT_31_MAX || height > PNG_UINT_31_MAX)
        png_error(png_ptr, "Invalid image size in IHDR");
     if ( width > (PNG_UINT_32_MAX
                   >> 3)      /* 8-byte RGBA pixels */
                   - 64       /* bigrowbuf hack */
                   - 1        /* filter byte */
                   - 7*8      /* rounding of width to multiple of 8 pixels */
                   - 8)       /* extra max_pixel_depth pad */
        png_warning(png_ptr, "Width is too large for libpng to process pixels");
  
     /* check other values */
     if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
        bit_depth != 8 && bit_depth != 16)
        png_error(png_ptr, "Invalid bit depth in IHDR");
  
     if (color_type < 0 || color_type == 1 ||
        color_type == 5 || color_type > 6)
        png_error(png_ptr, "Invalid color type in IHDR");
  
     if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
         ((color_type == PNG_COLOR_TYPE_RGB ||
           color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
           color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
        png_error(png_ptr, "Invalid color type/bit depth combination in IHDR");
  
     if (interlace_type >= PNG_INTERLACE_LAST)
        png_error(png_ptr, "Unknown interlace method in IHDR");
  
     if (compression_type != PNG_COMPRESSION_TYPE_BASE)
        png_error(png_ptr, "Unknown compression method in IHDR");
  
  #if defined(PNG_MNG_FEATURES_SUPPORTED)
     /* Accept filter_method 64 (intrapixel differencing) only if
      * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
      * 2. Libpng did not read a PNG signature (this filter_method is only
      *    used in PNG datastreams that are embedded in MNG datastreams) and
      * 3. The application called png_permit_mng_features with a mask that
      *    included PNG_FLAG_MNG_FILTER_64 and
      * 4. The filter_method is 64 and
      * 5. The color_type is RGB or RGBA
      */
     if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
        png_warning(png_ptr,"MNG features are not allowed in a PNG datastream");
     if(filter_type != PNG_FILTER_TYPE_BASE)
     {
       if(!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
          (filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
          ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
          (color_type == PNG_COLOR_TYPE_RGB ||
           color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
          png_error(png_ptr, "Unknown filter method in IHDR");
       if(png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
          png_warning(png_ptr, "Invalid filter method in IHDR");
     }
  #else
     if(filter_type != PNG_FILTER_TYPE_BASE)
        png_error(png_ptr, "Unknown filter method in IHDR");
  #endif
  
     info_ptr->width = width;
     info_ptr->height = height;
     info_ptr->bit_depth = (png_byte)bit_depth;
     info_ptr->color_type =(png_byte) color_type;
     info_ptr->compression_type = (png_byte)compression_type;
     info_ptr->filter_type = (png_byte)filter_type;
     info_ptr->interlace_type = (png_byte)interlace_type;
     if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
        info_ptr->channels = 1;
     else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
        info_ptr->channels = 3;
     else
        info_ptr->channels = 1;
     if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
        info_ptr->channels++;
     info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
  
     /* check for potential overflow */
     if (width > (PNG_UINT_32_MAX
                   >> 3)      /* 8-byte RGBA pixels */
                   - 64       /* bigrowbuf hack */
                   - 1        /* filter byte */
                   - 7*8      /* rounding of width to multiple of 8 pixels */
                   - 8)       /* extra max_pixel_depth pad */
        info_ptr->rowbytes = (png_size_t)0;
     else
        info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,width);
  }
  
  #if defined(PNG_oFFs_SUPPORTED)
  void PNGAPI
  png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
     png_int_32 offset_x, png_int_32 offset_y, int unit_type)
  {
     png_debug1(1, "in %s storage function\n", "oFFs");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     info_ptr->x_offset = offset_x;
     info_ptr->y_offset = offset_y;
     info_ptr->offset_unit_type = (png_byte)unit_type;
     info_ptr->valid |= PNG_INFO_oFFs;
  }
  #endif
  
  #if defined(PNG_pCAL_SUPPORTED)
  void PNGAPI
  png_set_pCAL(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)
  {
     png_uint_32 length;
     int i;
  
     png_debug1(1, "in %s storage function\n", "pCAL");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     length = png_strlen(purpose) + 1;
     png_debug1(3, "allocating purpose for info (%lu bytes)\n", length);
     info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
     if (info_ptr->pcal_purpose == NULL)
       {
         png_warning(png_ptr, "Insufficient memory for pCAL purpose.");
         return;
       }
     png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);
  
     png_debug(3, "storing X0, X1, type, and nparams in info\n");
     info_ptr->pcal_X0 = X0;
     info_ptr->pcal_X1 = X1;
     info_ptr->pcal_type = (png_byte)type;
     info_ptr->pcal_nparams = (png_byte)nparams;
  
     length = png_strlen(units) + 1;
     png_debug1(3, "allocating units for info (%lu bytes)\n", length);
     info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
     if (info_ptr->pcal_units == NULL)
       {
         png_warning(png_ptr, "Insufficient memory for pCAL units.");
         return;
       }
     png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);
  
     info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
        (png_uint_32)((nparams + 1) * png_sizeof(png_charp)));
     if (info_ptr->pcal_params == NULL)
       {
         png_warning(png_ptr, "Insufficient memory for pCAL params.");
         return;
       }
  
     info_ptr->pcal_params[nparams] = NULL;
  
     for (i = 0; i < nparams; i++)
     {
        length = png_strlen(params[i]) + 1;
        png_debug2(3, "allocating parameter %d for info (%lu bytes)\n", i, length);
        info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
        if (info_ptr->pcal_params[i] == NULL)
          {
            png_warning(png_ptr, "Insufficient memory for pCAL parameter.");
            return;
          }
        png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
     }
  
     info_ptr->valid |= PNG_INFO_pCAL;
  #ifdef PNG_FREE_ME_SUPPORTED
     info_ptr->free_me |= PNG_FREE_PCAL;
  #endif
  }
  #endif
  
  #if defined(PNG_READ_sCAL_SUPPORTED) || defined(PNG_WRITE_sCAL_SUPPORTED)
  #ifdef PNG_FLOATING_POINT_SUPPORTED
  void PNGAPI
  png_set_sCAL(png_structp png_ptr, png_infop info_ptr,
               int unit, double width, double height)
  {
     png_debug1(1, "in %s storage function\n", "sCAL");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     info_ptr->scal_unit = (png_byte)unit;
     info_ptr->scal_pixel_width = width;
     info_ptr->scal_pixel_height = height;
  
     info_ptr->valid |= PNG_INFO_sCAL;
  }
  #else
  #ifdef PNG_FIXED_POINT_SUPPORTED
  void PNGAPI
  png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
               int unit, png_charp swidth, png_charp sheight)
  {
     png_uint_32 length;
  
     png_debug1(1, "in %s storage function\n", "sCAL");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     info_ptr->scal_unit = (png_byte)unit;
  
     length = png_strlen(swidth) + 1;
     png_debug1(3, "allocating unit for info (%d bytes)\n", length);
     info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, length);
     if (info_ptr->scal_s_width == NULL)
     {
        png_warning(png_ptr,
         "Memory allocation failed while processing sCAL.");
     }
     png_memcpy(info_ptr->scal_s_width, swidth, (png_size_t)length);
  
     length = png_strlen(sheight) + 1;
     png_debug1(3, "allocating unit for info (%d bytes)\n", length);
     info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, length);
     if (info_ptr->scal_s_height == NULL)
     {
        png_free (png_ptr, info_ptr->scal_s_width);
        png_warning(png_ptr,
         "Memory allocation failed while processing sCAL.");
     }
     png_memcpy(info_ptr->scal_s_height, sheight, (png_size_t)length);
  
     info_ptr->valid |= PNG_INFO_sCAL;
  #ifdef PNG_FREE_ME_SUPPORTED
     info_ptr->free_me |= PNG_FREE_SCAL;
  #endif
  }
  #endif
  #endif
  #endif
  
  #if defined(PNG_pHYs_SUPPORTED)
  void PNGAPI
  png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
     png_uint_32 res_x, png_uint_32 res_y, int unit_type)
  {
     png_debug1(1, "in %s storage function\n", "pHYs");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     info_ptr->x_pixels_per_unit = res_x;
     info_ptr->y_pixels_per_unit = res_y;
     info_ptr->phys_unit_type = (png_byte)unit_type;
     info_ptr->valid |= PNG_INFO_pHYs;
  }
  #endif
  
  void PNGAPI
  png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
     png_colorp palette, int num_palette)
  {
  
     png_debug1(1, "in %s storage function\n", "PLTE");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
       {
         if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
           png_error(png_ptr, "Invalid palette length");
         else
         {
           png_warning(png_ptr, "Invalid palette length");
           return;
         }
       }
  
     /*
      * It may not actually be necessary to set png_ptr->palette here;
      * we do it for backward compatibility with the way the png_handle_tRNS
      * function used to do the allocation.
      */
  #ifdef PNG_FREE_ME_SUPPORTED
     png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
  #endif
  
     /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
        of num_palette entries,
        in case of an invalid PNG file that has too-large sample values. */
     png_ptr->palette = (png_colorp)png_malloc(png_ptr,
        PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color));
     png_memset(png_ptr->palette, 0, PNG_MAX_PALETTE_LENGTH *
        png_sizeof(png_color));
     png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof (png_color));
     info_ptr->palette = png_ptr->palette;
     info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
  
  #ifdef PNG_FREE_ME_SUPPORTED
     info_ptr->free_me |= PNG_FREE_PLTE;
  #else
     png_ptr->flags |= PNG_FLAG_FREE_PLTE;
  #endif
  
     info_ptr->valid |= PNG_INFO_PLTE;
  }
  
  #if defined(PNG_sBIT_SUPPORTED)
  void PNGAPI
  png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
     png_color_8p sig_bit)
  {
     png_debug1(1, "in %s storage function\n", "sBIT");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof (png_color_8));
     info_ptr->valid |= PNG_INFO_sBIT;
  }
  #endif
  
  #if defined(PNG_sRGB_SUPPORTED)
  void PNGAPI
  png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
  {
     png_debug1(1, "in %s storage function\n", "sRGB");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     info_ptr->srgb_intent = (png_byte)intent;
     info_ptr->valid |= PNG_INFO_sRGB;
  }
  
  void PNGAPI
  png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
     int intent)
  {
  #if defined(PNG_gAMA_SUPPORTED)
  #ifdef PNG_FLOATING_POINT_SUPPORTED
     float file_gamma;
  #endif
  #ifdef PNG_FIXED_POINT_SUPPORTED
     png_fixed_point int_file_gamma;
  #endif
  #endif
  #if defined(PNG_cHRM_SUPPORTED)
  #ifdef PNG_FLOATING_POINT_SUPPORTED
     float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
  #endif
  #ifdef PNG_FIXED_POINT_SUPPORTED
     png_fixed_point int_white_x, int_white_y, int_red_x, int_red_y, int_green_x,
        int_green_y, int_blue_x, int_blue_y;
  #endif
  #endif
     png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     png_set_sRGB(png_ptr, info_ptr, intent);
  
  #if defined(PNG_gAMA_SUPPORTED)
  #ifdef PNG_FLOATING_POINT_SUPPORTED
     file_gamma = (float).45455;
     png_set_gAMA(png_ptr, info_ptr, file_gamma);
  #endif
  #ifdef PNG_FIXED_POINT_SUPPORTED
     int_file_gamma = 45455L;
     png_set_gAMA_fixed(png_ptr, info_ptr, int_file_gamma);
  #endif
  #endif
  
  #if defined(PNG_cHRM_SUPPORTED)
  #ifdef PNG_FIXED_POINT_SUPPORTED
     int_white_x = 31270L;
     int_white_y = 32900L;
     int_red_x   = 64000L;
     int_red_y   = 33000L;
     int_green_x = 30000L;
     int_green_y = 60000L;
     int_blue_x  = 15000L;
     int_blue_y  =  6000L;
  
     png_set_cHRM_fixed(png_ptr, info_ptr,
        int_white_x, int_white_y, int_red_x, int_red_y, int_green_x, int_green_y,
        int_blue_x, int_blue_y);
  #endif
  #ifdef PNG_FLOATING_POINT_SUPPORTED
     white_x = (float).3127;
     white_y = (float).3290;
     red_x   = (float).64;
     red_y   = (float).33;
     green_x = (float).30;
     green_y = (float).60;
     blue_x  = (float).15;
     blue_y  = (float).06;
  
     png_set_cHRM(png_ptr, info_ptr,
        white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
  #endif
  #endif
  }
  #endif
  
  
  #if defined(PNG_iCCP_SUPPORTED)
  void PNGAPI
  png_set_iCCP(png_structp png_ptr, png_infop info_ptr,
               png_charp name, int compression_type,
               png_charp profile, png_uint_32 proflen)
  {
     png_charp new_iccp_name;
     png_charp new_iccp_profile;
     png_uint_32 length;
  
     png_debug1(1, "in %s storage function\n", "iCCP");
     if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
        return;
  
     length = png_strlen(name)+1;
     new_iccp_name = (png_charp)png_malloc_warn(png_ptr, length);
     if (new_iccp_name == NULL)
     {
        png_warning(png_ptr, "Insufficient memory to process iCCP chunk.");
        return;
     }
     png_memcpy(new_iccp_name, name, length);
     new_iccp_profile = (png_charp)png_malloc_warn(png_ptr, proflen);
     if (new_iccp_profile == NULL)
     {
        png_free (png_ptr, new_iccp_name);
        png_warning(png_ptr, "Insufficient memory to process iCCP profile.");
        return;
     }
     png_memcpy(new_iccp_profile, profile, (png_size_t)proflen);
  
     png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
  
     info_ptr->iccp_proflen = proflen;
     info_ptr->iccp_name = new_iccp_name;
     info_ptr->iccp_profile = new_iccp_profile;
     /* Compression is always zero but is here so the API and info structure
      * does not have to change if we introduce multiple compression types */
     info_ptr->iccp_compression = (png_byte)compression_type;
  #ifdef PNG_FREE_ME_SUPPORTED
     info_ptr->free_me |= PNG_FREE_ICCP;
  #endif
     info_ptr->valid |= PNG_INFO_iCCP;
  }
  #endif
  
  #if defined(PNG_TEXT_SUPPORTED)
  void PNGAPI
  png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
     int num_text)
  {
     int ret;
     ret=png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
     if (ret)
       png_error(png_ptr, "Insufficient memory to store text");
  }
  
  int /* PRIVATE */
  png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
     int num_text)
  {
     int i;
  
     png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
        "text" : (png_const_charp)png_ptr->chunk_name));
  
     if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
        return(0);
  
     /* Make sure we have enough space in the "text" array in info_struct
      * to hold all of the incoming text_ptr objects.
      */
     if (info_ptr->num_text + num_text > info_ptr->max_text)
     {
        if (info_ptr->text != NULL)
        {
           png_textp old_text;
           int old_max;
  
           old_max = info_ptr->max_text;
           info_ptr->max_text = info_ptr->num_text + num_text + 8;
           old_text = info_ptr->text;
           info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
              (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
           if (info_ptr->text == NULL)
             {
               png_free(png_ptr, old_text);
               return(1);
             }
           png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
              png_sizeof(png_text)));
           png_free(png_ptr, old_text);
        }
        else
        {
           info_ptr->max_text = num_text + 8;
           info_ptr->num_text = 0;
           info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
              (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
           if (info_ptr->text == NULL)
             return(1);
  #ifdef PNG_FREE_ME_SUPPORTED
           info_ptr->free_me |= PNG_FREE_TEXT;
  #endif
        }
        png_debug1(3, "allocated %d entries for info_ptr->text\n",
           info_ptr->max_text);
     }
     for (i = 0; i < num_text; i++)
     {
        png_size_t text_length,key_len;
        png_size_t lang_len,lang_key_len;
        png_textp textp = &(info_ptr->text[info_ptr->num_text]);
  
        if (text_ptr[i].key == NULL)
            continue;
  
        key_len = png_strlen(text_ptr[i].key);
  
        if(text_ptr[i].compression <= 0)
        {
          lang_len = 0;
          lang_key_len = 0;
        }
        else
  #ifdef PNG_iTXt_SUPPORTED
        {
          /* set iTXt data */
          if (text_ptr[i].lang != NULL)
            lang_len = png_strlen(text_ptr[i].lang);
          else
            lang_len = 0;
          if (text_ptr[i].lang_key != NULL)
            lang_key_len = png_strlen(text_ptr[i].lang_key);
          else
            lang_key_len = 0;
        }
  #else
        {
          png_warning(png_ptr, "iTXt chunk not supported.");
          continue;
        }
  #endif
  
        if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
        {
           text_length = 0;
  #ifdef PNG_iTXt_SUPPORTED
           if(text_ptr[i].compression > 0)
              textp->compression = PNG_ITXT_COMPRESSION_NONE;
           else
  #endif
              textp->compression = PNG_TEXT_COMPRESSION_NONE;
        }
        else
        {
           text_length = png_strlen(text_ptr[i].text);
           textp->compression = text_ptr[i].compression;
        }
  
        textp->key = (png_charp)png_malloc_warn(png_ptr,
           (png_uint_32)(key_len + text_length + lang_len + lang_key_len + 4));
        if (textp->key == NULL)
          return(1);
        png_debug2(2, "Allocated %lu bytes at %x in png_set_text\n",
           (png_uint_32)(key_len + lang_len + lang_key_len + text_length + 4),
           (int)textp->key);
  
        png_memcpy(textp->key, text_ptr[i].key,
           (png_size_t)(key_len));
        *(textp->key+key_len) = '\0';
  #ifdef PNG_iTXt_SUPPORTED
        if (text_ptr[i].compression > 0)
        {
           textp->lang=textp->key + key_len + 1;
           png_memcpy(textp->lang, text_ptr[i].lang, lang_len);
           *(textp->lang+lang_len) = '\0';
           textp->lang_key=textp->lang + lang_len + 1;
           png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
           *(textp->lang_key+lang_key_len) = '\0';
           textp->text=textp->lang_key + lang_key_len + 1;
        }
        else
  #endif
        {
  #ifdef PNG_iTXt_SUPPORTED
           textp->lang=NULL;
           textp->lang_key=NULL;
  #endif
           textp->text=textp->key + key_len + 1;
        }
        if(text_length)
           png_memcpy(textp->text, text_ptr[i].text,
              (png_size_t)(text_length));
        *(textp->text+text_length) = '\0';
  
  #ifdef PNG_iTXt_SUPPORTED
        if(textp->compression > 0)
        {
           textp->text_length = 0;
           textp->itxt_length = text_length;
        }
        else
  #endif
        {
           textp->text_length = text_length;
  #ifdef PNG_iTXt_SUPPORTED
           textp->itxt_length = 0;
  #endif
        }
        info_ptr->num_text++;
        png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
     }
     return(0);
  }
  #endif
  
  #if defined(PNG_tIME_SUPPORTED)
  void PNGAPI
  png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
  {
     png_debug1(1, "in %s storage function\n", "tIME");
     if (png_ptr == NULL || info_ptr == NULL ||
         (png_ptr->mode & PNG_WROTE_tIME))
        return;
  
     png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof (png_time));
     info_ptr->valid |= PNG_INFO_tIME;
  }
  #endif
  
  #if defined(PNG_tRNS_SUPPORTED)
  void PNGAPI
  png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
     png_bytep trans, int num_trans, png_color_16p trans_values)
  {
     png_debug1(1, "in %s storage function\n", "tRNS");
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     if (trans != NULL)
     {
         /*
          * It may not actually be necessary to set png_ptr->trans here;
          * we do it for backward compatibility with the way the png_handle_tRNS
          * function used to do the allocation.
          */
  #ifdef PNG_FREE_ME_SUPPORTED
         png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
  #endif
         /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
         png_ptr->trans = info_ptr->trans = (png_bytep)png_malloc(png_ptr,
             (png_uint_32)PNG_MAX_PALETTE_LENGTH);
         if (num_trans <= PNG_MAX_PALETTE_LENGTH)
           png_memcpy(info_ptr->trans, trans, (png_size_t)num_trans);
  #ifdef PNG_FREE_ME_SUPPORTED
         info_ptr->free_me |= PNG_FREE_TRNS;
  #else
         png_ptr->flags |= PNG_FLAG_FREE_TRNS;
  #endif
     }
  
     if (trans_values != NULL)
     {
        png_memcpy(&(info_ptr->trans_values), trans_values,
           png_sizeof(png_color_16));
        if (num_trans == 0)
          num_trans = 1;
     }
     info_ptr->num_trans = (png_uint_16)num_trans;
     info_ptr->valid |= PNG_INFO_tRNS;
  }
  #endif
  
  #if defined(PNG_sPLT_SUPPORTED)
  void PNGAPI
  png_set_sPLT(png_structp png_ptr,
               png_infop info_ptr, png_sPLT_tp entries, int nentries)
  {
      png_sPLT_tp np;
      int i;
  
      if (png_ptr == NULL || info_ptr == NULL)
         return;
  
      np = (png_sPLT_tp)png_malloc_warn(png_ptr,
          (info_ptr->splt_palettes_num + nentries) * png_sizeof(png_sPLT_t));
      if (np == NULL)
      {
        png_warning(png_ptr, "No memory for sPLT palettes.");
        return;
      }
  
      png_memcpy(np, info_ptr->splt_palettes,
             info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
      png_free(png_ptr, info_ptr->splt_palettes);
      info_ptr->splt_palettes=NULL;
  
      for (i = 0; i < nentries; i++)
      {
          png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
          png_sPLT_tp from = entries + i;
          png_uint_32 length;
  
          length = png_strlen(from->name) + 1;
          to->name = (png_charp)png_malloc_warn(png_ptr, length);
          if (to->name == NULL)
          {
             png_warning(png_ptr,
               "Out of memory while processing sPLT chunk");
          }
          /* TODO: use png_malloc_warn */
          png_memcpy(to->name, from->name, length);
          to->entries = (png_sPLT_entryp)png_malloc_warn(png_ptr,
              from->nentries * png_sizeof(png_sPLT_entry));
          /* TODO: use png_malloc_warn */
          png_memcpy(to->entries, from->entries,
              from->nentries * png_sizeof(png_sPLT_entry));
          if (to->entries == NULL)
          {
             png_warning(png_ptr,
               "Out of memory while processing sPLT chunk");
             png_free(png_ptr,to->name);
             to->name = NULL;
          }
          to->nentries = from->nentries;
          to->depth = from->depth;
      }
  
      info_ptr->splt_palettes = np;
      info_ptr->splt_palettes_num += nentries;
      info_ptr->valid |= PNG_INFO_sPLT;
  #ifdef PNG_FREE_ME_SUPPORTED
      info_ptr->free_me |= PNG_FREE_SPLT;
  #endif
  }
  #endif /* PNG_sPLT_SUPPORTED */
  
  #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
  void PNGAPI
  png_set_unknown_chunks(png_structp png_ptr,
     png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)
  {
      png_unknown_chunkp np;
      int i;
  
      if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0)
          return;
  
      np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
          (info_ptr->unknown_chunks_num + num_unknowns) *
          png_sizeof(png_unknown_chunk));
      if (np == NULL)
      {
         png_warning(png_ptr,
            "Out of memory while processing unknown chunk.");
         return;
      }
  
      png_memcpy(np, info_ptr->unknown_chunks,
             info_ptr->unknown_chunks_num * png_sizeof(png_unknown_chunk));
      png_free(png_ptr, info_ptr->unknown_chunks);
      info_ptr->unknown_chunks=NULL;
  
      for (i = 0; i < num_unknowns; i++)
      {
          png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
          png_unknown_chunkp from = unknowns + i;
  
          png_memcpy((png_charp)to->name, 
                     (png_charp)from->name, 
                     png_sizeof(from->name));
          to->name[png_sizeof(to->name)-1] = '\0';
  
          to->data = (png_bytep)png_malloc_warn(png_ptr, from->size);
          if (to->data == NULL)
          {
             png_warning(png_ptr,
                "Out of memory while processing unknown chunk.");
          }
          else
          {
             png_memcpy(to->data, from->data, from->size);
             to->size = from->size;
  
             /* note our location in the read or write sequence */
             to->location = (png_byte)(png_ptr->mode & 0xff);
          }
      }
  
      info_ptr->unknown_chunks = np;
      info_ptr->unknown_chunks_num += num_unknowns;
  #ifdef PNG_FREE_ME_SUPPORTED
      info_ptr->free_me |= PNG_FREE_UNKN;
  #endif
  }
  void PNGAPI
  png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr,
     int chunk, int location)
  {
     if(png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
           (int)info_ptr->unknown_chunks_num)
        info_ptr->unknown_chunks[chunk].location = (png_byte)location;
  }
  #endif
  
  #if defined(PNG_1_0_X) || defined(PNG_1_2_X)
  #if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
      defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
  void PNGAPI
  png_permit_empty_plte (png_structp png_ptr, int empty_plte_permitted)
  {
     /* This function is deprecated in favor of png_permit_mng_features()
        and will be removed from libpng-1.3.0 */
     png_debug(1, "in png_permit_empty_plte, DEPRECATED.\n");
     if (png_ptr == NULL)
        return;
     png_ptr->mng_features_permitted = (png_byte)
       ((png_ptr->mng_features_permitted & (~PNG_FLAG_MNG_EMPTY_PLTE)) |
       ((empty_plte_permitted & PNG_FLAG_MNG_EMPTY_PLTE)));
  }
  #endif
  #endif
  
  #if defined(PNG_MNG_FEATURES_SUPPORTED)
  png_uint_32 PNGAPI
  png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features)
  {
     png_debug(1, "in png_permit_mng_features\n");
     if (png_ptr == NULL)
        return (png_uint_32)0;
     png_ptr->mng_features_permitted =
       (png_byte)(mng_features & PNG_ALL_MNG_FEATURES);
     return (png_uint_32)png_ptr->mng_features_permitted;
  }
  #endif
  
  #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
  void PNGAPI
  png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_bytep
     chunk_list, int num_chunks)
  {
      png_bytep new_list, p;
      int i, old_num_chunks;
      if (png_ptr == NULL)
         return;
      if (num_chunks == 0)
      {
        if(keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
          png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
        else
          png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
  
        if(keep == PNG_HANDLE_CHUNK_ALWAYS)
          png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
        else
          png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
        return;
      }
      if (chunk_list == NULL)
        return;
      old_num_chunks=png_ptr->num_chunk_list;
      new_list=(png_bytep)png_malloc(png_ptr,
         (png_uint_32)(5*(num_chunks+old_num_chunks)));
      if(png_ptr->chunk_list != NULL)
      {
         png_memcpy(new_list, png_ptr->chunk_list,
            (png_size_t)(5*old_num_chunks));
         png_free(png_ptr, png_ptr->chunk_list);
         png_ptr->chunk_list=NULL;
      }
      png_memcpy(new_list+5*old_num_chunks, chunk_list,
         (png_size_t)(5*num_chunks));
      for (p=new_list+5*old_num_chunks+4, i=0; i<num_chunks; i++, p+=5)
         *p=(png_byte)keep;
      png_ptr->num_chunk_list=old_num_chunks+num_chunks;
      png_ptr->chunk_list=new_list;
  #ifdef PNG_FREE_ME_SUPPORTED
      png_ptr->free_me |= PNG_FREE_LIST;
  #endif
  }
  #endif
  
  #if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
  void PNGAPI
  png_set_read_user_chunk_fn(png_structp png_ptr, png_voidp user_chunk_ptr,
     png_user_chunk_ptr read_user_chunk_fn)
  {
     png_debug(1, "in png_set_read_user_chunk_fn\n");
     if (png_ptr == NULL)
        return;
     png_ptr->read_user_chunk_fn = read_user_chunk_fn;
     png_ptr->user_chunk_ptr = user_chunk_ptr;
  }
  #endif
  
  #if defined(PNG_INFO_IMAGE_SUPPORTED)
  void PNGAPI
  png_set_rows(png_structp png_ptr, png_infop info_ptr, png_bytepp row_pointers)
  {
     png_debug1(1, "in %s storage function\n", "rows");
  
     if (png_ptr == NULL || info_ptr == NULL)
        return;
  
     if(info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
        png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
     info_ptr->row_pointers = row_pointers;
     if(row_pointers)
        info_ptr->valid |= PNG_INFO_IDAT;
  }
  #endif
  
  #ifdef PNG_WRITE_SUPPORTED
  void PNGAPI
  png_set_compression_buffer_size(png_structp png_ptr, png_uint_32 size)
  {
      if (png_ptr == NULL)
         return;
      if(png_ptr->zbuf)
         png_free(png_ptr, png_ptr->zbuf);
      png_ptr->zbuf_size = (png_size_t)size;
      png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size);
      png_ptr->zstream.next_out = png_ptr->zbuf;
      png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
  }
  #endif
  
  void PNGAPI
  png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask)
  {
     if (png_ptr && info_ptr)
        info_ptr->valid &= ~mask;
  }
  
  
  #ifndef PNG_1_0_X
  #ifdef PNG_ASSEMBLER_CODE_SUPPORTED
  /* function was added to libpng 1.2.0 and should always exist by default */
  void PNGAPI
  png_set_asm_flags (png_structp png_ptr, png_uint_32 asm_flags)
  {
  /* Obsolete as of libpng-1.2.20 and will be removed from libpng-1.4.0 */
      if (png_ptr != NULL)
      png_ptr->asm_flags = 0;
  }
  
  /* this function was added to libpng 1.2.0 */
  void PNGAPI
  png_set_mmx_thresholds (png_structp png_ptr,
                          png_byte mmx_bitdepth_threshold,
                          png_uint_32 mmx_rowbytes_threshold)
  {
  /* Obsolete as of libpng-1.2.20 and will be removed from libpng-1.4.0 */
      if (png_ptr == NULL)
         return;
  }
  #endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
  
  #ifdef PNG_SET_USER_LIMITS_SUPPORTED
  /* this function was added to libpng 1.2.6 */
  void PNGAPI
  png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
      png_uint_32 user_height_max)
  {
      /* Images with dimensions larger than these limits will be
       * rejected by png_set_IHDR().  To accept any PNG datastream
       * regardless of dimensions, set both limits to 0x7ffffffL.
       */
      if(png_ptr == NULL) return;
      png_ptr->user_width_max = user_width_max;
      png_ptr->user_height_max = user_height_max;
  }
  #endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
  
  #endif /* ?PNG_1_0_X */
  #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
  