diff options
Diffstat (limited to 'test/read-png.c')
| -rw-r--r-- | test/read-png.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/test/read-png.c b/test/read-png.c index 23f91e831..e7e2a92ca 100644 --- a/test/read-png.c +++ b/test/read-png.c @@ -47,9 +47,9 @@ premultiply_data (png_structp png, unsigned char alpha = base[3]; unsigned long p; - red = (unsigned) red * (unsigned) alpha / 255; - green = (unsigned) green * (unsigned) alpha / 255; - blue = (unsigned) blue * (unsigned) alpha / 255; + red = ((unsigned) red * (unsigned) alpha + 127) / 255; + green = ((unsigned) green * (unsigned) alpha + 127) / 255; + blue = ((unsigned) blue * (unsigned) alpha + 127) / 255; p = (alpha << 24) | (red << 16) | (green << 8) | (blue << 0); memcpy (base, &p, sizeof (unsigned long)); } |