[FFmpeg-cvslog] avcodec/mpeg: Initialize quarter_sample parameter from previous thread.

[Andriy Gelman]

ffmpeg | branch: master | Andriy Gelman <andriy.gelman at gmail.com> | Wed Dec 12 23:57:35 2018 -0500| [5282db5929f25ca9566a47ad217794842b364afc] | committer: Michael Niedermayer

avcodec/mpeg: Initialize quarter_sample parameter from previous thread.

Fixes #7410.
The value of sub-pixel precision for me/mc can change during an Intra frame. In multi-threaded decoding this change is not propagated to other frame threads causing decoding artifacts. This patch initializes the sub-pixel precision parameter from previous thread, which fixes the issue.

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=5282db5929f25ca9566a47ad217794842b364afc
---

 libavcodec/mpegvideo.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index d4d3bea649..dbb6ab9b39 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -538,6 +538,8 @@ int ff_mpeg_update_thread_context(AVCodecContext *dst,
     s->avctx->width         = s1->avctx->width;
     s->avctx->height        = s1->avctx->height;
 
+    s->quarter_sample       = s1->quarter_sample;
+
     s->coded_picture_number = s1->coded_picture_number;
     s->picture_number       = s1->picture_number;