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/* pngget.c - retrieval of values from info struct
*
* libpng 1.00
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
* Copyright (c) 1996, 1997 Andreas Dilger
* Copyright (c) 1998, Glenn Randers-Pehrson
* March 7, 1998
*/
#define PNG_INTERNAL
#include "png.h"
png_uint_32
png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
{
if (png_ptr != NULL && info_ptr != NULL)
return(info_ptr->valid & flag);
else
return(0);
}
png_uint_32
png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
return(info_ptr->rowbytes);
else
return(0);
}
#ifdef PNG_EASY_ACCESS_SUPPORTED
/* easy access to info, added in libpng-0.99 */
png_uint_32
png_get_image_width(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
{
return info_ptr->width;
}
return (0);
}
png_uint_32
png_get_image_height(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
{
return info_ptr->height;
}
return (0);
}
png_byte
png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
{
return info_ptr->bit_depth;
}
return (0);
}
png_byte
png_get_color_type(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
{
return info_ptr->color_type;
}
return (0);
}
png_byte
png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
{
return info_ptr->filter_type;
}
return (0);
}
png_byte
png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
{
return info_ptr->interlace_type;
}
return (0);
}
png_byte
png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
{
return info_ptr->compression_type;
}
return (0);
}
png_uint_32
png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_x_pixels_per_meter");
if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
return (0);
else return (info_ptr->x_pixels_per_unit);
}
else
#endif
return (0);
}
png_uint_32
png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_y_pixels_per_meter");
if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
return (0);
else return (info_ptr->y_pixels_per_unit);
}
else
#endif
return (0);
}
png_uint_32
png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_pixels_per_meter");
if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER ||
info_ptr->x_pixels_per_unit != info_ptr->y_pixels_per_unit)
return (0);
else return (info_ptr->x_pixels_per_unit);
}
else
#endif
return (0);
}
float
png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_aspect_ratio");
if (info_ptr->x_pixels_per_unit == 0)
return ((float)0.0);
else
return ((float)info_ptr->y_pixels_per_unit
/(float)info_ptr->x_pixels_per_unit);
}
else
#endif
return ((float)0.0);
}
png_uint_32
png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
return (0);
else return (info_ptr->x_offset);
}
else
#endif
return (0);
}
png_uint_32
png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
return (0);
else return (info_ptr->y_offset);
}
else
#endif
return (0);
}
png_uint_32
png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
return (0);
else return (info_ptr->x_offset);
}
else
#endif
return (0);
}
png_uint_32
png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
{
png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
return (0);
else return (info_ptr->y_offset);
}
else
#endif
return (0);
}
#ifdef PNG_INCH_CONVERSIONS
png_uint_32
png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
{
return ((png_uint_32)((float)png_get_pixels_per_meter(png_ptr, info_ptr)
*.03937 +.5)
}
png_uint_32
png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
{
return ((png_uint_32)((float)png_get_x_pixels_per_meter(png_ptr, info_ptr)
*.03937 +.5)
}
png_uint_32
png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
{
return ((png_uint_32)((float)png_get_y_pixels_per_meter(png_ptr, info_ptr)
*.03937 +.5)
}
float
png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
{
return ((float)png_get_x_offset_microns(png_ptr, info_ptr)
*.03937/1000000. +.5)
}
float
png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
{
return ((float)png_get_y_offset_microns(png_ptr, info_ptr)
*.03937/1000000. +.5)
}
#if defined(PNG_READ_pHYs_SUPPORTED)
png_uint_32
png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
{
png_uint_32 retval = 0;
if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs)
{
png_debug1(1, "in %s retrieval function\n", "pHYs");
if (res_x != NULL)
{
*res_x = info_ptr->x_pixels_per_unit;
retval |= PNG_INFO_pHYs;
}
if (res_y != NULL)
{
*res_y = info_ptr->y_pixels_per_unit;
retval |= PNG_INFO_pHYs;
}
if (unit_type != NULL)
{
*unit_type = (int)info_ptr->phys_unit_type;
retval |= PNG_INFO_pHYs;
if(unit_type == 1)
{
if (res_x != NULL) *res_x = (png_uint_32)(*res_x * 39.37 + .50);
if (res_y != NULL) *res_y = (png_uint_32)(*res_y * 39.37 + .50);
}
}
}
return (retval);
}
#endif
#endif /* PNG_INCH_CONVERSIONS */
/* png_get_channels really belongs in here, too, but it's been around longer */
#endif /* PNG_EASY_ACCESS_SUPPORTED */
png_byte
png_get_channels(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
return(info_ptr->channels);
else
return (0);
}
png_bytep
png_get_signature(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
return(info_ptr->signature);
else
return (NULL);
}
#if defined(PNG_READ_bKGD_SUPPORTED)
png_uint_32
png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
png_color_16p *background)
{
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
&& background != NULL)
{
png_debug1(1, "in %s retrieval function\n", "bKGD");
*background = &(info_ptr->background);
return (PNG_INFO_bKGD);
}
return (0);
}
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
png_uint_32
png_get_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)
{
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
{
png_debug1(1, "in %s retrieval function\n", "cHRM");
if (white_x != NULL)
*white_x = (double)info_ptr->x_white;
if (white_y != NULL)
*white_y = (double)info_ptr->y_white;
if (red_x != NULL)
*red_x = (double)info_ptr->x_red;
if (red_y != NULL)
*red_y = (double)info_ptr->y_red;
if (green_x != NULL)
*green_x = (double)info_ptr->x_green;
if (green_y != NULL)
*green_y = (double)info_ptr->y_green;
if (blue_x != NULL)
*blue_x = (double)info_ptr->x_blue;
if (blue_y != NULL)
*blue_y = (double)info_ptr->y_blue;
return (PNG_INFO_cHRM);
}
return (0);
}
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
png_uint_32
png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
{
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
&& file_gamma != NULL)
{
png_debug1(1, "in %s retrieval function\n", "gAMA");
*file_gamma = (double)info_ptr->gamma;
return (PNG_INFO_gAMA);
}
return (0);
}
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
png_uint_32
png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
{
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
&& file_srgb_intent != NULL)
{
png_debug1(1, "in %s retrieval function\n", "sRGB");
*file_srgb_intent = (int)info_ptr->srgb_intent;
return (PNG_INFO_sRGB);
}
return (0);
}
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
png_uint_32
png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
{
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
&& hist != NULL)
{
png_debug1(1, "in %s retrieval function\n", "hIST");
*hist = info_ptr->hist;
return (PNG_INFO_hIST);
}
return (0);
}
#endif
png_uint_32
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)
{
if (png_ptr != NULL && info_ptr != NULL && width != NULL && height != NULL &&
bit_depth != NULL && color_type != NULL)
{
int pixel_depth, channels;
png_uint_32 rowbytes_per_pixel;
png_debug1(1, "in %s retrieval function\n", "IHDR");
*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;
/* check for potential overflow of rowbytes */
if (*color_type == PNG_COLOR_TYPE_PALETTE)
channels = 1;
else if (*color_type & PNG_COLOR_MASK_COLOR)
channels = 3;
else
channels = 1;
if (*color_type & PNG_COLOR_MASK_ALPHA)
channels++;
pixel_depth = *bit_depth * channels;
rowbytes_per_pixel = (pixel_depth + 7) >> 3;
if ((*width > (png_uint_32)2147483647L/rowbytes_per_pixel))
{
png_warning(png_ptr,
"Width too large for libpng to process image data.");
}
return (1);
}
return (0);
}
#if defined(PNG_READ_oFFs_SUPPORTED)
png_uint_32
png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
png_uint_32 *offset_x, png_uint_32 *offset_y, int *unit_type)
{
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
&& offset_x != NULL && offset_y != NULL && unit_type != NULL)
{
png_debug1(1, "in %s retrieval function\n", "oFFs");
*offset_x = info_ptr->x_offset;
*offset_y = info_ptr->y_offset;
*unit_type = (int)info_ptr->offset_unit_type;
return (PNG_INFO_oFFs);
}
return (0);
}
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
png_uint_32
png_get_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)
{
if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pCAL &&
purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
nparams != NULL && units != NULL && params != NULL)
{
png_debug1(1, "in %s retrieval function\n", "pCAL");
*purpose = info_ptr->pcal_purpose;
*X0 = info_ptr->pcal_X0;
*X1 = info_ptr->pcal_X1;
*type = (int)info_ptr->pcal_type;
*nparams = (int)info_ptr->pcal_nparams;
*units = info_ptr->pcal_units;
*params = info_ptr->pcal_params;
return (PNG_INFO_pCAL);
}
return (0);
}
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
png_uint_32
png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
{
png_uint_32 retval = 0;
if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs)
{
png_debug1(1, "in %s retrieval function\n", "pHYs");
if (res_x != NULL)
{
*res_x = info_ptr->x_pixels_per_unit;
retval |= PNG_INFO_pHYs;
}
if (res_y != NULL)
{
*res_y = info_ptr->y_pixels_per_unit;
retval |= PNG_INFO_pHYs;
}
if (unit_type != NULL)
{
*unit_type = (int)info_ptr->phys_unit_type;
retval |= PNG_INFO_pHYs;
}
}
return (retval);
}
#endif
png_uint_32
png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
int *num_palette)
{
if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_PLTE &&
palette != NULL)
{
png_debug1(1, "in %s retrieval function\n", "PLTE");
*palette = info_ptr->palette;
*num_palette = info_ptr->num_palette;
png_debug1(3, "num_palette = %d\n", *num_palette);
return (PNG_INFO_PLTE);
}
return (0);
}
#if defined(PNG_READ_sBIT_SUPPORTED)
png_uint_32
png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
{
if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_sBIT &&
sig_bit != NULL)
{
png_debug1(1, "in %s retrieval function\n", "sBIT");
*sig_bit = &(info_ptr->sig_bit);
return (PNG_INFO_sBIT);
}
return (0);
}
#endif
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
png_uint_32
png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
int *num_text)
{
if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
{
png_debug1(1, "in %s retrieval function\n",
(png_ptr->chunk_name[0] == '\0' ? "text"
: (png_const_charp)png_ptr->chunk_name));
if (text_ptr != NULL)
*text_ptr = info_ptr->text;
if (num_text != NULL)
*num_text = info_ptr->num_text;
return ((png_uint_32)info_ptr->num_text);
}
return(0);
}
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
png_uint_32
png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
{
if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_tIME &&
mod_time != NULL)
{
png_debug1(1, "in %s retrieval function\n", "tIME");
*mod_time = &(info_ptr->mod_time);
return (PNG_INFO_tIME);
}
return (0);
}
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
png_uint_32
png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
png_bytep *trans, int *num_trans, png_color_16p *trans_values)
{
png_uint_32 retval = 0;
if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
{
png_debug1(1, "in %s retrieval function\n", "tRNS");
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
if (trans != NULL)
{
*trans = info_ptr->trans;
retval |= PNG_INFO_tRNS;
}
if (trans_values != NULL)
*trans_values = &(info_ptr->trans_values);
}
else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
{
if (trans_values != NULL)
{
*trans_values = &(info_ptr->trans_values);
retval |= PNG_INFO_tRNS;
}
if(trans != NULL)
*trans = NULL;
}
if(num_trans != NULL)
{
*num_trans = info_ptr->num_trans;
retval |= PNG_INFO_tRNS;
}
}
return (retval);
}
#endif