As i have no chance on IRC I will try here…
I have an audio/video communication through Asterisk 11.7 using G711 and H264. With an old version of a peer I have no problem but with a new one, I have a lot of lag on the video, audio is ok.
I have done a tcpdump and when I look at the rtp packet, i can see that the PPS, SPS and SSRC are changed between the 2 legs on video but not on audio.
Here an extract from tcpdump which describe the problem on video:
4195 37.948480 126.96.36.199 188.8.131.52 H264 63 PT=H264, SSRC=0x15C5673, Seq=0, Time=9000 NAL unit - Sequence parameter set 4196 37.948511 184.108.40.206 220.127.116.11 H264 60 PT=H264, SSRC=0x15C5673, Seq=1, Time=9000 NAL unit - Picture parameter set 4197 37.949560 18.104.22.168 22.214.171.124 H264 571 PT=H264, SSRC=0x15C5673, Seq=2, Time=9000 NAL unit - Coded slice of an IDR picture ... 4513 39.130015 126.96.36.199 188.8.131.52 H264 593 PT=H264, SSRC=0x15C5673, Seq=91, Time=117000 NAL unit - Coded slice of a non-IDR picture 4514 39.130175 184.108.40.206 220.127.116.11 H264 593 PT=H264, SSRC=0x27837A17, Seq=14299, Time=108000 NAL unit - Coded slice of a non-IDR picture 4518 39.130620 18.104.22.168 22.214.171.124 H264 783 PT=H264, SSRC=0x27837A17, Seq=14300, Time=108000 NAL unit - Coded slice of a non-IDR picture
And the audio extraction:
4210 37.984291 126.96.36.199 188.8.131.52 RTP 214 PT=ITU-T G.711 PCMA, SSRC=0xB965895, Seq=0, Time=18240 4211 37.984445 184.108.40.206 220.127.116.11 RTP 214 PT=ITU-T G.711 PCMA, SSRC=0xB965895, Seq=0, Time=18240, Mark
I’m not sure my problems come from here but why audio is pass through but not the video?
I have made no change on Asterisk so what kind of parameter can affect the peer to decode?
Any help would be appreciate.