diff options
Diffstat (limited to 'libass/ass_bitmap.c')
| -rw-r--r-- | libass/ass_bitmap.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/libass/ass_bitmap.c b/libass/ass_bitmap.c index d3186b4..5e2ca77 100644 --- a/libass/ass_bitmap.c +++ b/libass/ass_bitmap.c @@ -395,16 +395,14 @@ void ass_add_bitmaps_c(uint8_t *dst, intptr_t dst_stride, } } -void ass_sub_bitmaps_c(uint8_t *dst, intptr_t dst_stride, - uint8_t *src, intptr_t src_stride, - intptr_t width, intptr_t height) +void ass_imul_bitmaps_c(uint8_t *dst, intptr_t dst_stride, + uint8_t *src, intptr_t src_stride, + intptr_t width, intptr_t height) { - short out; uint8_t* end = dst + dst_stride * height; while (dst < end) { for (unsigned j = 0; j < width; ++j) { - out = dst[j] - src[j]; - dst[j] = FFMAX(out, 0); + dst[j] = (dst[j] * (255 - src[j]) + 255) >> 8; } dst += dst_stride; src += src_stride; |