[FFmpeg-devel] RTP mark bit not passed to parse_packet
Luca Abeni
lucabe72
Thu Jan 15 23:05:18 CET 2009
Hi Alexandre,
sorry for not replying to the previous emails: I've been offline for
some time :)
Anyway, I see that you already solved most of the problems.
Alexandre FERRIEUX - FT/RD/SIRP/ASF/SOFTL wrote:
[...]
> Further investigation (printing the incremented counter of frames in
> av_find_stream_info()) shows that it takes a fairly large number of
> frames to decide, unless an EOF occurs I guess. But in RTP/UDP there's
> no EOF of course, and I was repeatedly streaming the same short
> sequence, so when the seqnum/timestamps had a discontinuity, maybe the
> guessing work was reset...
>
> Anyway, streaming a longer sequence works.
>
> A few ancillary questions:
>
> 1) This means all those frames are accumulated in memory, right ?
>
> 2) What extra info could I have provided (eithr in the SDP or in
> command-line options) so that this guessing work be avoided ?
I do not know the H.263-related RFCs, but mpeg4 and H.264 allow encoding
the video "global headers" in the SDP (in the "config" tag for mpeg4 or
in the "sprop-parameters-set" tag for H.264). If H.263 allows something
similar (you have to check the RFC) then this kind of out-of-band global
headers should provide all the needed information to
av_find_stream_info() (the SDP parser will have to put this information
in the extradata field of the AVCodecContext).
Luca
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