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libpng/pngget.c
Glenn Randers-Pehrson 31aee0d0c0 [devel] 
Fixed point APIs are now supported throughout (no missing APIs).
  Internal fixed point arithmetic support exists for all internal floating
    point operations.
  sCAL validates the floating point strings it is passed.
  Safe, albeit rudimentary, Watcom support is provided by PNG_API_RULE==2
  Two new APIs exist to get the number of passes without turning on the
    PNG_INTERLACE transform and to get the number of rows in the current
    pass.
  A new test program, pngvalid.c, validates the gamma code.
  Errors in the 16 bit gamma correction (overflows) have been corrected.
  cHRM chunk testing is done consistently (previously the floating point
    API bypassed it, because the test really didn't work on FP, now the test
    is performed on the actual values to be stored in the PNG file so it
    works in the FP case too.)
  Most floating point APIs now simply call the fixed point APIs after
    converting the values to the fixed point form used in the PNG file.
  The standard headers no longer include zlib.h, which is currently only
    required for pngstruct.h and can therefore be internal.
  (Patches by John Bowler)
2010-07-29 17:39:14 -05:00

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/* pngget.c - retrieval of values from info struct
*
* Last changed in libpng 1.4.1 [July 29, 2010]
* 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
*
*/
#include "pngpriv.h"
#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
png_uint_32 PNGAPI
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_size_t PNGAPI
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_INFO_IMAGE_SUPPORTED
png_bytepp PNGAPI
png_get_rows(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
return(info_ptr->row_pointers);
else
return(0);
}
#endif
#ifdef PNG_EASY_ACCESS_SUPPORTED
/* Easy access to info, added in libpng-0.99 */
png_uint_32 PNGAPI
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 PNGAPI
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 PNGAPI
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 PNGAPI
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 PNGAPI
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 PNGAPI
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 PNGAPI
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 PNGAPI
png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_pHYs_SUPPORTED
if (info_ptr->valid & PNG_INFO_pHYs)
{
png_debug1(1, "in %s retrieval function", "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
return (0);
#endif
return (0);
}
png_uint_32 PNGAPI
png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_pHYs_SUPPORTED
if (info_ptr->valid & PNG_INFO_pHYs)
{
png_debug1(1, "in %s retrieval function", "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
return (0);
#endif
return (0);
}
png_uint_32 PNGAPI
png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_pHYs_SUPPORTED
if (info_ptr->valid & PNG_INFO_pHYs)
{
png_debug1(1, "in %s retrieval function", "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
return (0);
#endif
return (0);
}
#ifdef PNG_FLOATING_POINT_SUPPORTED
float PNGAPI
png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_pHYs_SUPPORTED
if (info_ptr->valid & PNG_INFO_pHYs)
{
png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio");
if (info_ptr->x_pixels_per_unit == 0)
return ((float)0.0);
else
return ((float)((float)info_ptr->y_pixels_per_unit
/(float)info_ptr->x_pixels_per_unit));
}
#else
return (0.0);
#endif
return ((float)0.0);
}
#endif
png_int_32 PNGAPI
png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_oFFs_SUPPORTED
if (info_ptr->valid & PNG_INFO_oFFs)
{
png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns");
if (info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
return (0);
else
return (info_ptr->x_offset);
}
#else
return (0);
#endif
return (0);
}
png_int_32 PNGAPI
png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_oFFs_SUPPORTED
if (info_ptr->valid & PNG_INFO_oFFs)
{
png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns");
if (info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
return (0);
else
return (info_ptr->y_offset);
}
#else
return (0);
#endif
return (0);
}
png_int_32 PNGAPI
png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_oFFs_SUPPORTED
if (info_ptr->valid & PNG_INFO_oFFs)
{
png_debug1(1, "in %s retrieval function", "png_get_x_offset_pixels");
if (info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
return (0);
else
return (info_ptr->x_offset);
}
#else
return (0);
#endif
return (0);
}
png_int_32 PNGAPI
png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
#ifdef PNG_oFFs_SUPPORTED
if (info_ptr->valid & PNG_INFO_oFFs)
{
png_debug1(1, "in %s retrieval function", "png_get_y_offset_pixels");
if (info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
return (0);
else
return (info_ptr->y_offset);
}
#else
return (0);
#endif
return (0);
}
#ifdef PNG_INCH_CONVERSIONS_SUPPORTED
static png_uint_32
ppi_from_ppm(png_uint_32 ppm)
{
#if 0
/* The convertion is *(2.54/100), in binary (32 digits):
* .00000110100000001001110101001001
*/
png_uint_32 t1001, t1101;
ppm >>= 1; /* .1 */
t1001 = ppm + (ppm >> 3); /* .1001 */
t1101 = t1001 + (ppm >> 1); /* .1101 */
ppm >>= 20; /* .000000000000000000001 */
t1101 += t1101 >> 15; /* .1101000000000001101 */
t1001 >>= 11; /* .000000000001001 */
t1001 += t1001 >> 12; /* .000000000001001000000001001 */
ppm += t1001; /* .000000000001001000001001001 */
ppm += t1101; /* .110100000001001110101001001 */
return (ppm + 16) >> 5;/* .00000110100000001001110101001001 */
#else
/* The argument is a PNG unsigned integer, so it is not permitted
* to be bigger than 2^31.
*/
png_fixed_point result;
if (ppm <= PNG_UINT_31_MAX && png_muldiv(&result, ppm, 127, 5000))
return result;
/* Overflow. */
return 0;
#endif
}
png_uint_32 PNGAPI
png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
{
return ppi_from_ppm(png_get_pixels_per_meter(png_ptr, info_ptr));
}
png_uint_32 PNGAPI
png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
{
return ppi_from_ppm(png_get_x_pixels_per_meter(png_ptr, info_ptr));
}
png_uint_32 PNGAPI
png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
{
return ppi_from_ppm(png_get_y_pixels_per_meter(png_ptr, info_ptr));
}
#ifdef PNG_FIXED_POINT_SUPPORTED
static png_fixed_point
png_fixed_inches_from_microns(png_structp png_ptr, png_int_32 microns)
{
/* Convert from metres * 1,000,000 to inches * 100,000, meters to
* inches is simply *(100/2.54), so we want *(10/2.54) == 1000/254.
* Notice that this can overflow - a warning is output and 0 is
* returned.
*/
return png_muldiv_warn(png_ptr, microns, 500, 127);
}
png_fixed_point PNGAPI
png_get_x_offset_inches_fixed(png_structp png_ptr, png_infop info_ptr)
{
return png_fixed_inches_from_microns(png_ptr,
png_get_x_offset_microns(png_ptr, info_ptr));
}
#endif
#ifdef PNG_FIXED_POINT_SUPPORTED
png_fixed_point PNGAPI
png_get_y_offset_inches_fixed(png_structp png_ptr, png_infop info_ptr)
{
return png_fixed_inches_from_microns(png_ptr,
png_get_y_offset_microns(png_ptr, info_ptr));
}
#endif
#ifdef PNG_FLOATING_POINT_SUPPORTED
float PNGAPI
png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
{
/* To avoid the overflow do the conversion directly in floating
* point.
*/
return png_get_x_offset_microns(png_ptr, info_ptr) * .00003937f;
}
#endif
#ifdef PNG_FLOATING_POINT_SUPPORTED
float PNGAPI
png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
{
/* To avoid the overflow do the conversion directly in floating
* point.
*/
return png_get_y_offset_microns(png_ptr, info_ptr) * .00003937f;
}
#endif
#ifdef PNG_pHYs_SUPPORTED
png_uint_32 PNGAPI
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", "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 * .0254 + .50);
if (res_y != NULL) *res_y = (png_uint_32)(*res_y * .0254 + .50);
}
}
}
return (retval);
}
#endif /* PNG_pHYs_SUPPORTED */
#endif /* PNG_INCH_CONVERSIONS_SUPPORTED */
/* png_get_channels really belongs in here, too, but it's been around longer */
#endif /* PNG_EASY_ACCESS_SUPPORTED */
png_byte PNGAPI
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 PNGAPI
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);
}
#ifdef PNG_bKGD_SUPPORTED
png_uint_32 PNGAPI
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", "bKGD");
*background = &(info_ptr->background);
return (PNG_INFO_bKGD);
}
return (0);
}
#endif
#ifdef PNG_cHRM_SUPPORTED
#ifdef PNG_FLOATING_POINT_SUPPORTED
png_uint_32 PNGAPI
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", "cHRM");
if (white_x != NULL)
*white_x = png_float(png_ptr, info_ptr->x_white, "cHRM white X");
if (white_y != NULL)
*white_y = png_float(png_ptr, info_ptr->y_white, "cHRM white Y");
if (red_x != NULL)
*red_x = png_float(png_ptr, info_ptr->x_red, "cHRM red X");
if (red_y != NULL)
*red_y = png_float(png_ptr, info_ptr->y_red, "cHRM red Y");
if (green_x != NULL)
*green_x = png_float(png_ptr, info_ptr->x_green, "cHRM green X");
if (green_y != NULL)
*green_y = png_float(png_ptr, info_ptr->y_green, "cHRM green Y");
if (blue_x != NULL)
*blue_x = png_float(png_ptr, info_ptr->x_blue, "cHRM blue X");
if (blue_y != NULL)
*blue_y = png_float(png_ptr, info_ptr->y_blue, "cHRM blue Y");
return (PNG_INFO_cHRM);
}
return (0);
}
#endif
#ifdef PNG_FIXED_POINT_SUPPORTED
png_uint_32 PNGAPI
png_get_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 retrieval function", "cHRM");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
{
if (white_x != NULL)
*white_x = info_ptr->x_white;
if (white_y != NULL)
*white_y = info_ptr->y_white;
if (red_x != NULL)
*red_x = info_ptr->x_red;
if (red_y != NULL)
*red_y = info_ptr->y_red;
if (green_x != NULL)
*green_x = info_ptr->x_green;
if (green_y != NULL)
*green_y = info_ptr->y_green;
if (blue_x != NULL)
*blue_x = info_ptr->x_blue;
if (blue_y != NULL)
*blue_y = info_ptr->y_blue;
return (PNG_INFO_cHRM);
}
return (0);
}
#endif
#endif
#ifdef PNG_gAMA_SUPPORTED
png_uint_32 PNGFAPI
png_get_gAMA_fixed(png_structp png_ptr, png_infop info_ptr,
png_fixed_point *file_gamma)
{
png_debug1(1, "in %s retrieval function", "gAMA");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
&& file_gamma != NULL)
{
*file_gamma = info_ptr->gamma;
return (PNG_INFO_gAMA);
}
return (0);
}
#ifdef PNG_FLOATING_POINT_SUPPORTED
png_uint_32 PNGAPI
png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
{
png_fixed_point igamma;
png_uint_32 ok = png_get_gAMA_fixed(png_ptr, info_ptr, &igamma);
if (ok)
*file_gamma = png_float(png_ptr, igamma, "png_get_gAMA");
return ok;
}
#endif
#endif
#ifdef PNG_sRGB_SUPPORTED
png_uint_32 PNGAPI
png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
{
png_debug1(1, "in %s retrieval function", "sRGB");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
&& file_srgb_intent != NULL)
{
*file_srgb_intent = (int)info_ptr->srgb_intent;
return (PNG_INFO_sRGB);
}
return (0);
}
#endif
#ifdef PNG_iCCP_SUPPORTED
png_uint_32 PNGAPI
png_get_iCCP(png_structp png_ptr, png_infop info_ptr,
png_charpp name, int *compression_type,
png_bytepp profile, png_uint_32 *proflen)
{
png_debug1(1, "in %s retrieval function", "iCCP");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
&& name != NULL && profile != NULL && proflen != NULL)
{
*name = info_ptr->iccp_name;
*profile = info_ptr->iccp_profile;
/* Compression_type is a dummy so the API won't have to change
* if we introduce multiple compression types later.
*/
*proflen = (int)info_ptr->iccp_proflen;
*compression_type = (int)info_ptr->iccp_compression;
return (PNG_INFO_iCCP);
}
return (0);
}
#endif
#ifdef PNG_sPLT_SUPPORTED
png_uint_32 PNGAPI
png_get_sPLT(png_structp png_ptr, png_infop info_ptr,
png_sPLT_tpp spalettes)
{
if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
{
*spalettes = info_ptr->splt_palettes;
return ((png_uint_32)info_ptr->splt_palettes_num);
}
return (0);
}
#endif
#ifdef PNG_hIST_SUPPORTED
png_uint_32 PNGAPI
png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
{
png_debug1(1, "in %s retrieval function", "hIST");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
&& hist != NULL)
{
*hist = info_ptr->hist;
return (PNG_INFO_hIST);
}
return (0);
}
#endif
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);
}
#ifdef PNG_oFFs_SUPPORTED
png_uint_32 PNGAPI
png_get_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 retrieval function", "oFFs");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
&& offset_x != NULL && offset_y != NULL && unit_type != NULL)
{
*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
#ifdef PNG_pCAL_SUPPORTED
png_uint_32 PNGAPI
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)
{
png_debug1(1, "in %s retrieval function", "pCAL");
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)
{
*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
#ifdef PNG_sCAL_SUPPORTED
#ifdef PNG_FIXED_POINT_SUPPORTED
png_uint_32 PNGAPI
png_get_sCAL_fixed(png_structp png_ptr, png_infop info_ptr,
int *unit, png_fixed_point *width, png_fixed_point *height)
{
if (png_ptr != NULL && info_ptr != NULL &&
(info_ptr->valid & PNG_INFO_sCAL))
{
*unit = info_ptr->scal_unit;
/*TODO: make this work */
*width = png_fixed(png_ptr, atof(info_ptr->scal_s_width), "sCAL width");
*height = png_fixed(png_ptr, atof(info_ptr->scal_s_height),
"sCAL height");
return (PNG_INFO_sCAL);
}
return(0);
}
#endif
#ifdef PNG_FLOATING_POINT_SUPPORTED
png_uint_32 PNGAPI
png_get_sCAL(png_structp png_ptr, png_infop info_ptr,
int *unit, double *width, double *height)
{
if (png_ptr != NULL && info_ptr != NULL &&
(info_ptr->valid & PNG_INFO_sCAL))
{
*unit = info_ptr->scal_unit;
*width = atof(info_ptr->scal_s_width);
*height = atof(info_ptr->scal_s_height);
return (PNG_INFO_sCAL);
}
return(0);
}
#endif
png_uint_32 PNGAPI
png_get_sCAL_s(png_structp png_ptr, png_infop info_ptr,
int *unit, png_charpp width, png_charpp height)
{
if (png_ptr != NULL && info_ptr != NULL &&
(info_ptr->valid & PNG_INFO_sCAL))
{
*unit = info_ptr->scal_unit;
*width = info_ptr->scal_s_width;
*height = info_ptr->scal_s_height;
return (PNG_INFO_sCAL);
}
return(0);
}
#endif
#ifdef PNG_pHYs_SUPPORTED
png_uint_32 PNGAPI
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;
png_debug1(1, "in %s retrieval function", "pHYs");
if (png_ptr != NULL && info_ptr != NULL &&
(info_ptr->valid & PNG_INFO_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 PNGAPI
png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
int *num_palette)
{
png_debug1(1, "in %s retrieval function", "PLTE");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE)
&& palette != NULL)
{
*palette = info_ptr->palette;
*num_palette = info_ptr->num_palette;
png_debug1(3, "num_palette = %d", *num_palette);
return (PNG_INFO_PLTE);
}
return (0);
}
#ifdef PNG_sBIT_SUPPORTED
png_uint_32 PNGAPI
png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
{
png_debug1(1, "in %s retrieval function", "sBIT");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
&& sig_bit != NULL)
{
*sig_bit = &(info_ptr->sig_bit);
return (PNG_INFO_sBIT);
}
return (0);
}
#endif
#ifdef PNG_TEXT_SUPPORTED
png_uint_32 PNGAPI
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",
(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);
}
if (num_text != NULL)
*num_text = 0;
return(0);
}
#endif
#ifdef PNG_tIME_SUPPORTED
png_uint_32 PNGAPI
png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
{
png_debug1(1, "in %s retrieval function", "tIME");
if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)
&& mod_time != NULL)
{
*mod_time = &(info_ptr->mod_time);
return (PNG_INFO_tIME);
}
return (0);
}
#endif
#ifdef PNG_tRNS_SUPPORTED
png_uint_32 PNGAPI
png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
{
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", "tRNS");
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
if (trans_alpha != NULL)
{
*trans_alpha = info_ptr->trans_alpha;
retval |= PNG_INFO_tRNS;
}
if (trans_color != NULL)
*trans_color = &(info_ptr->trans_color);
}
else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
{
if (trans_color != NULL)
{
*trans_color = &(info_ptr->trans_color);
retval |= PNG_INFO_tRNS;
}
if (trans_alpha != NULL)
*trans_alpha = NULL;
}
if (num_trans != NULL)
{
*num_trans = info_ptr->num_trans;
retval |= PNG_INFO_tRNS;
}
}
return (retval);
}
#endif
#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
png_uint_32 PNGAPI
png_get_unknown_chunks(png_structp png_ptr, png_infop info_ptr,
png_unknown_chunkpp unknowns)
{
if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL)
{
*unknowns = info_ptr->unknown_chunks;
return ((png_uint_32)info_ptr->unknown_chunks_num);
}
return (0);
}
#endif
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
png_byte PNGAPI
png_get_rgb_to_gray_status (png_structp png_ptr)
{
return (png_byte)(png_ptr ? png_ptr->rgb_to_gray_status : 0);
}
#endif
#ifdef PNG_USER_CHUNKS_SUPPORTED
png_voidp PNGAPI
png_get_user_chunk_ptr(png_structp png_ptr)
{
return (png_ptr ? png_ptr->user_chunk_ptr : NULL);
}
#endif
png_size_t PNGAPI
png_get_compression_buffer_size(png_structp png_ptr)
{
return (png_ptr ? png_ptr->zbuf_size : 0L);
}
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
/* These functions were added to libpng 1.2.6 and were enabled
* by default in libpng-1.4.0 */
png_uint_32 PNGAPI
png_get_user_width_max (png_structp png_ptr)
{
return (png_ptr ? png_ptr->user_width_max : 0);
}
png_uint_32 PNGAPI
png_get_user_height_max (png_structp png_ptr)
{
return (png_ptr ? png_ptr->user_height_max : 0);
}
/* This function was added to libpng 1.4.0 */
png_uint_32 PNGAPI
png_get_chunk_cache_max (png_structp png_ptr)
{
return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
}
/* This function was added to libpng 1.4.1 */
png_alloc_size_t PNGAPI
png_get_chunk_malloc_max (png_structp png_ptr)
{
return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
}
#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
/* These functions were added to libpng 1.4.0 */
#ifdef PNG_IO_STATE_SUPPORTED
png_uint_32 PNGAPI
png_get_io_state (png_structp png_ptr)
{
return png_ptr->io_state;
}
png_bytep PNGAPI
png_get_io_chunk_name (png_structp png_ptr)
{
return png_ptr->chunk_name;
}
#endif /* ?PNG_IO_STATE_SUPPORTED */
#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
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