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authorMichael Niedermayer <michael@niedermayer.cc>2017-09-08 23:29:13 +0200
committerMichael Niedermayer <michael@niedermayer.cc>2017-09-11 13:28:21 +0200
commitb590758298cc6f7bac710ebaecb99a4de878c7f8 (patch)
treeb6aae1cff2f32c3a11c4aa8fd9a7f6fc9ab15f74
parent8eb8882af5ccc6efd715783a151ddedba4587b9d (diff)
downloadffmpeg-b590758298cc6f7bac710ebaecb99a4de878c7f8.tar.gz
avcodec/scpr: optimize shift loop.
Speeds code up from 50sec to 15sec Fixes Timeout Fixes: 3242/clusterfuzz-testcase-5811951672229888 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Reviewed-by: James Almer <jamrial@gmail.com> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> (cherry picked from commit 981f04b2ae2d6e0355386aaff39840eb5d390a36) Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
-rw-r--r--libavcodec/scpr.c13
1 files changed, 12 insertions, 1 deletions
diff --git a/libavcodec/scpr.c b/libavcodec/scpr.c
index b4cc7df07f..78a6d5c0cd 100644
--- a/libavcodec/scpr.c
+++ b/libavcodec/scpr.c
@@ -824,8 +824,19 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
if (ret < 0)
return ret;
+ // scale up each sample by 8
for (y = 0; y < avctx->height; y++) {
- for (x = 0; x < avctx->width * 4; x++) {
+ // If the image is sufficiently aligned, compute 8 samples at once
+ if (!(((uintptr_t)dst) & 7)) {
+ uint64_t *dst64 = (uint64_t *)dst;
+ int w = avctx->width>>1;
+ for (x = 0; x < w; x++) {
+ dst64[x] = (dst64[x] << 3) & 0xFCFCFCFCFCFCFCFCULL;
+ }
+ x *= 8;
+ } else
+ x = 0;
+ for (; x < avctx->width * 4; x++) {
dst[x] = dst[x] << 3;
}
dst += frame->linesize[0];