[gst-devel] RTP clocking issue

Zeeshan Ali zeenix at gmail.com
Tue Nov 8 04:08:06 CET 2005

Hello everyone,
   As most of you people are already aware that we need to have some
mechanism to sync the clocks of the sender and receiver in an RTP
session. A typical simple RTP pipeline looks something like:

sender: alsasrc ! SOMECODEC_encoder ! SOMECODEC_payloader ! rtpbin
receiver: rtpbin ! SOMECODEC_depayloader ! SOMECODEC_decoder ! alsasink

   Here are some thoughts and the problems with these thoughts:

1. Implement a clock in the rtpbin/depayloader, based on the
timestamps on the packets received and the system-clock. The problem
with this approach is when we use the rtpbin in full-duplex mode, like
this: alsasrc ! SOMECODEC_encoder ! SOMECODEC_payloader ! rtpbin !
SOMECODEC_depayloader ! SOMECODEC_decoder ! alsasink
 . Now in this case, gstreamer will pick-up the clock of the alsasrc
instead of rtpbin an therefore our solution wont work out.

2. Make the rtpbin/depayloader translates the timestamps on the
packets according to the pipeline clock, *somehow* ? I dont know if
that is possible or not and how. So please throw some light on this

3. Any other suggestion?

Zeeshan Ali

More information about the gstreamer-devel mailing list