[gst-devel] RTP sync and sender report ntp timestamps

Jon Burgess jkburges at gmail.com
Wed Dec 17 02:46:07 CET 2008

Hi all,

I'm currently looking at syncing of two independent RTP sources (one video,
one audio), both of which are recorded by our application to be played back
later, in sync.

I understand that part of the RTP/RTCP spec is that RTCP sender reports sent
periodically (e.g. every few seconds) contain a ntp timestamp which
correlates ntp time to RTP timestamps, in theory allowing accurate
synchronisation between multiple sources.

My question is: do any of the gstreamer rtp related elements take account of
the ntp timestamps in sender reports and adjust buffer timestamps
accordingly?  Which element(s) do RTCP processing?

My video source is a RTSP/mpeg4 part2 network encoder, and the relevant
gst-launch equivalent of my pipeline looks something like:

> gst-launch uridecodebin uri="rtsp://someurl" ! queue ! decodebin2 ....

in case that can help somebody direct me...

The audio source is received by something other than a g-streamer pipeline

Thanks in advance,
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/gstreamer-devel/attachments/20081217/bc82d8ac/attachment.htm>

More information about the gstreamer-devel mailing list