[libpng15] Fixes for multiple calls to png_read_update_info.

These fixes attend to most of the errors revealed in pngvalid, however doing
the gamma work twice results in inaccuracies that can't be easily fixed.
There is now a warning in the code if this is going to happen.
This commit is contained in:
John Bowler
2011-10-14 18:19:47 -05:00
committed by Glenn Randers-Pehrson
parent 5c1905caae
commit 07772cba07
10 changed files with 130 additions and 78 deletions

View File

@@ -157,19 +157,21 @@ struct png_struct_def
png_uint_32 flush_rows; /* number of rows written since last flush */
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
#ifdef PNG_READ_GAMMA_SUPPORTED
int gamma_shift; /* number of "insignificant" bits in 16-bit gamma */
png_fixed_point gamma; /* file gamma value */
png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
png_bytep gamma_table; /* gamma table for 8-bit depth files */
png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
png_bytep gamma_from_1; /* converts from 1.0 to screen */
png_bytep gamma_to_1; /* converts from file to 1.0 */
png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)