void PNGAPI
png_set_IHDR(png_const_structrp png_ptr, png_inforp 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", "IHDR");
if (png_ptr == NULL || info_ptr == NULL)
return;
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;
png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
info_ptr->compression_type, info_ptr->filter_type);
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
info_ptr->channels = 1;
else if ((info_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
info_ptr->channels = 3;
else
info_ptr->channels = 1;
if ((info_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0)
info_ptr->channels++;
info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
}
png_uint_32 PNGAPI
png_get_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 retrieval function", "IHDR");
if (png_ptr == NULL || info_ptr == NULL || width == NULL ||
height == NULL || bit_depth == NULL || color_type == NULL)
return (0);
*width = info_ptr->width;
*height = info_ptr->height;
*bit_depth = info_ptr->bit_depth;
*color_type = info_ptr->color_type;
if (compression_type != NULL)
*compression_type = info_ptr->compression_type;
if (filter_type != NULL)
*filter_type = info_ptr->filter_type;
if (interlace_type != NULL)
*interlace_type = info_ptr->interlace_type;
/* This is redundant if we can be sure that the info_ptr values were all
* assigned in png_set_IHDR(). We do the check anyhow in case an
* application has ignored our advice not to mess with the members
* of info_ptr directly.
*/
png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
info_ptr->compression_type, info_ptr->filter_type);
return (1);
}
