[FFmpeg-user] HEVC decoding from multicast

[Andrey Utkin]

I think right solution would be to attach AVFormatContext on UDP
stream, an demux it until you have got AVPacket of needed video
stream, with AVPacket.flags & AV_PKT_FLAG_KEY (or sth like that). This
means you've got keyframe, you can decode just it and nothing else,
and you should get a "full" frame. I'm not sure if it possible to end
up with somewhat corrupted decoded frame in this situation, and how to
detect that situation, but this is possible to check in practice. As a
hint you could check AVPacket.flags for AV_PKT_FLAG_CORRUPT and
decoded frame for AV_FRAME_FLAG_CORRUPT. You can also set "err_detect"
option to "explode" for decoding context. Looking at libavcodec/hevc.c
i can see that setting "explode+crccheck" value to "err_detect" can
probably be even better.

-- 
Andrey Utkin