[libpng16] Added missing parentheses to a macro definition

(Contributed by github.com/irwir)
2018-07-01 23:32:08 -04:00 · 2018-07-01 23:32:08 -04:00 · 2471434d29
commit 2471434d29
parent 8a05766cb7
1 changed files with 1 additions and 1 deletions
--- a/pngwrite.c
+++ b/pngwrite.c
@ -1636,7 +1636,7 @@ png_write_image_16bit(png_voidp argument)
 * calculation can be done to 15 bits of accuracy; however, the output needs to
 * be scaled in the range 0..255*65535, so include that scaling here.
 */
-#   define UNP_RECIPROCAL(alpha) ((((0xffff*0xff)<<7)+(alpha>>1))/alpha)
+#   define UNP_RECIPROCAL(alpha) ((((0xffff*0xff)<<7)+((alpha)>>1))/(alpha))

 static png_byte
 png_unpremultiply(png_uint_32 component, png_uint_32 alpha,