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RTP H.264 stream freezing on first frame

Posted: 09 Feb 2014 18:19
by eliba
Hi everyone,

I have encountered a strange problem while playing an RTP H.264 stream using VLC player.

I am developing firmware for an IP camera designed to be used with specialized software. By default, the camera's RTSP streamer had a bug where in each GOP, the SPS, PPS, SEI and IDR-frame were all grouped, and the stream simply consisted of an SPS NAL unit, followed by several P-slices. The PPS, SEI, and IDR-frame were all hidden inside the payload of the SPS packet. This caused the target software to be unable to play the stream, yet VLC player worked just fine.

After fixing it and properly splitting the various NAL units, the stream works properly on the target client, but now it works only partially with VLC - sometimes it works well, other times it freezes after showing 1-2 frames.
I've uploaded wireshark logs and VLC logs for both scenarios (old stream, new stream):

https://www.dropbox.com/s/kk4m04toudijb82/new.log
https://www.dropbox.com/s/gyg39osmhqi7p1r/New.pcapng

https://www.dropbox.com/s/ewank7m3itt8jcr/old.log
https://www.dropbox.com/s/jk08a4nq8cuog76/Old.pcapng

Any help would be grealy appreciated.

Re: RTP H.264 stream freezing on first frame

Posted: 13 Feb 2014 10:48
by Jean-Baptiste Kempf
It might be a live555 issue. VLC version?

Re: RTP H.264 stream freezing on first frame

Posted: 13 Feb 2014 10:57
by eliba
Right now I'm using 2.1.3 Rincewind on Windows 8 x64. The problem persists in older versions too, on windows 7 and ubuntu as well.

Re: RTP H.264 stream freezing on first frame

Posted: 13 Feb 2014 11:05
by Jean-Baptiste Kempf
You might need to ask live555 RTSP specialists.

Re: RTP H.264 stream freezing on first frame

Posted: 13 Feb 2014 11:06
by eliba
Any suggestions on where I could find some of those?

Re: RTP H.264 stream freezing on first frame

Posted: 13 Feb 2014 12:09
by Jean-Baptiste Kempf
live555 mailing list.

Re: RTP H.264 stream freezing on first frame

Posted: 13 Feb 2014 13:08
by eliba
Thanks, I'll try asking over there