[FFmpeg-devel] [RFC] H.264: Supporting Recovery Point SEIs

Jason Garrett-Glaser darkshikari
Fri Dec 25 20:56:57 CET 2009

x264 will soon be committing Periodic Intra Refresh, an extremely
powerful feature for low-latency, high-resilience streaming.  This
will involve using SEI Recovery Points as seek points in H.264 video
files.  This already works partially with container formats like MKV
and MP4 that flag keyframes.  However, there is the following, massive

The standard specifies that, upon seeking to an SEI Recovery Point,
that the decoder shall not display the video until recovery_frames_cnt
frames have been decoded.

This is relied upon heavily in Periodic Intra Refresh.

How should this be implemented in ffmpeg?  Should the decoder return 0
for every frame decoded after seeking until recovery_frames_cnt is

Dark Shikari

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