Playback of RTP stream using gstreamer

[Wim Taymans]

On 01/05/2012 10:33 AM, amolnatekar wrote:
> Hi,
>
> We have a thirdparty server which streams live data over RTP using the
> following rtp profiles:
>
>   1) H.264 Video using the RTP profile for H264 i.e. RFC 3984
>   2) AAC audio using the RTP profile for MPEG4-Generic Audio (Aac-hbr mode)
> i.e. RFC 3640
>
> The contents of sdp file received from the server are as below (There is no
> RTSP/RTCP protocol, the sdp file is received externally by some other
> means):
>
> v=0
> o=VLSS 10765500 10765500 IN IP4 192.168.0.133
> s=VLSS
> c=IN IP4 239.255.255.6
> t=0 0
> m=video 25000 RTP/AVP 96
> a=rtpmap:96 H264/1000
> a=fmtp:96 profile-level-id=
> m=audio 25002 RTP/AVP 97
> a=rtpmap:97 mpeg4-generic/16000/1
> a=mpeg4-esid:101
> a=fmtp:97 streamtype=5; profile-level-id=15; config=1408; mode=AAC-hbr;
> SizeLength=13; indexlength=3; indexdeltalength=3
>
> we tried playing the video using the following pipeline:
>
> gst-launch-0.10 udpsrc multicast-iface=eth0 uri=udp://239.255.255.6:25000
> caps='application/x-rtp, media=(string)video, clock-rate=(int)90000,
> encoding-name=(string)H264, profile-level-id=(string)\"\", payload=(int)96'
> ! rtph264depay ! ffdec_h264 ! ffmpegcolorspace ! ximagesink
>
> The video playback jerks in between with the following message:
>
> gstbasesink.c(2597): gst_base_sink_is_too_late ():
> /GstPipeline:pipeline0/GstXImageSink:ximagesink0:
> There may be a timestamping problem, or this computer is too slow.
> WARNING: from element /GstPipeline:pipeline0/GstXImageSink:ximagesink0: A
> lot of buffers are being dropped.
Add a gstrtpjitterbuffer after the udpsrc and play with the latency 
property.

Wim

> However when we use sync=false the playback is fine. Tried analyzing the
> timing parameters using -v option and fakesink and it seems the timing is
> incremental.
>
> We suspect that the following can create the issue:
>
> 1) Clock Rate as per the SDP file is 1000 however in caps we are using
> 90000. We tried with 1000 but the pipeline didn't execute throwing the
> following error: WARNING: erroneous pipeline: could not link udpsrc0 to
> rtph264depay0
>
> 2) The frame-rate of this video is 50 fps. The pipeline is getting wrong
> frame rate info which can create this issue.
>
> The playback of this sdp file using vlc plays fine without any jerks and A/V
> sync issues.
>
> Thanks,
> Amol
>
> --
> View this message in context: http://gstreamer-devel.966125.n4.nabble.com/Playback-of-RTP-stream-using-gstreamer-tp4264837p4264837.html
> Sent from the GStreamer-devel mailing list archive at Nabble.com.
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