[FFmpeg-trac] #9657(avformat:new): SSRC change on an RTP stream should lead to BYE

[FFmpeg]

#9657: SSRC change on an RTP stream should lead to BYE
-------------------------------------+----------------------------------
             Reporter:  do_coredump  |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avformat     |                  Version:  4.0.6
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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 Summary of the bug:

 when receiving an elementary live video stream (e.g. h264) and the sender
 of the stream restarts, then the receiving ffmpeg entity ignores all
 incoming packets due to a different SSRC.  This is bad when the sender is
 an embedded system which might restart any time.

 I propose to return RTP_BYE in case a different SSRC is received by the
 demuxer in ffmpeg

 Claus
 How to reproduce:
 {{{
 SDP file :
 -----------------
 v=0
 t=0 0
 m=video 35004 RTP/AVP 96
 c=IN IP4 127.0.0.1
 a=rtpmap:96 H264/90000
 ------------------
 * run a receiving ffmpeg instance
 ** ffmpeg -protocol_whitelist udp,file,crypto,rtp  -i foo.sdp -vcodec copy
 -acodec copy foo.mp4
 * run an ffmpeg version that creates an RTP stream
 ** ffmpeg -re  -i /tmp/sd.mp4 -vcodec copy -an -f rtp rtp:/127.0.0.1:35004
 * kill this instance and restart it (without restarting the receiver)
 ** ffmpeg -re  -i /tmp/sd.mp4 -vcodec copy -an -f rtp rtp:/127.0.0.1:35004

 Output on the receiving instance:

 output on the first receiving instance (relevant output only) :
 [sdp @ 0x55a8cba18780] RTP: dropping old packet received too late
     Last message repeated 528 times

 built on ffmpeg version  origin/release/4.0
 }}}
 Patches should be submitted to the ffmpeg-devel mailing list and not this
 bug tracker.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/9657>
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