/* pngread.c - read a PNG file
*
- * Last changed in libpng 1.6.32 [August 24, 2017]
+ * Last changed in libpng 1.6.33 [September 28, 2017]
* Copyright (c) 1998-2002,2004,2006-2017 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.)
mode = PNG_ALPHA_PNG;
output_gamma = PNG_DEFAULT_sRGB;
}
-
+
+ if ((change & PNG_FORMAT_FLAG_ASSOCIATED_ALPHA) != 0)
+ {
+ mode = PNG_ALPHA_OPTIMIZED;
+ change &= ~PNG_FORMAT_FLAG_ASSOCIATED_ALPHA;
+ }
+
/* If 'do_local_background' is set check for the presence of gamma
* correction; this is part of the work-round for the libpng bug
* described above.
else if (do_local_compose != 0) /* internal error */
png_error(png_ptr, "png_image_read: alpha channel lost");
+ if ((format & PNG_FORMAT_FLAG_ASSOCIATED_ALPHA) != 0) {
+ info_format |= PNG_FORMAT_FLAG_ASSOCIATED_ALPHA;
+ }
+
if (info_ptr->bit_depth == 16)
info_format |= PNG_FORMAT_FLAG_LINEAR;