[FFmpeg-devel] [PATCH] avcodec/utils: Optimize ff_color_frame()

[Michael Niedermayer]

Fixes: Timeout
Fixes: 10709/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5630617975259136

Before change: Executed clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5630617975259136 in 28285 ms
After change:  Executed clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5630617975259136 in  9395 ms

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/utils.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index d519b16092..963924a9ca 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -423,8 +423,12 @@ void ff_color_frame(AVFrame *frame, const int c[4])
         int height = is_chroma ? AV_CEIL_RSHIFT(frame->height, desc->log2_chroma_h) : frame->height;
         for (y = 0; y < height; y++) {
             if (desc->comp[0].depth >= 9) {
-                for (x = 0; x<bytes; x++)
-                    ((uint16_t*)dst)[x] = c[p];
+                if (!y) {
+                    for (x = 0; x<bytes; x++)
+                        ((uint16_t*)dst)[x] = c[p];
+                } else {
+                    memcpy(dst, frame->data[p], 2*bytes);
+                }
             }else
                 memset(dst, c[p], bytes);
             dst += frame->linesize[p];
-- 
2.20.1