<div dir="ltr"><div><div>Many thanks for the response. </div>I posted my answers to mailing list. :) </div>Sure, I have no problems to make some code, but it's necessary to understand what kind of components should i set there. And do I have to run some unix deamon to get reference clock for all my devices. Or it's not strictly necessary. </div><div class="gmail_extra"> <div class="gmail_quote">On Mon, Nov 28, 2016 at 11:32 PM, Sebastian Dröge <<a href="mailto:sebastian@centricular.com" target="_blank">sebastian@centricular.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Tue, 2016-11-22 at 06:27 -0800, LC wrote: > Hei, hei! > > I am testing rtsp stream synchronization abilities. > My use case is like this : 2 rtsp live streams in 2 filesinks. > > I am not going to use any mux element to get done synchronization inside > that element. Otherwise i need to demux to get each frame from each specific > rtspsrc to specific filesink. What are your RTSP senders? GStreamer based or something else? If something else, what kind features does that software stack give you, what kind of configuration related to synchronization and time can you do? > I am testing with this pipeline and want to get first frame synchronised but > i can't find the correct way. Here is that pipeline: gst-launch-1.0 -e > rtspsrc rfc7273-sync=true ntp-time-source=running-time > location=some/media.smp ! rtph264depay ! h264parse ! mp4mux ! filesink > location=file115.mp4 rtspsrc rfc7273-sync=true ntp-time-source=running-time > location=some/media2.smp ! rtph264depay ! h264parse ! mp4mux ! filesink > location=file145.mp4 In what way do you want the two files to be synchronized? They should start with exactly the same frame, or ...? > I also noticed comment on rfc7273-sync feature : "(requires clock and offset > to be provided)". And how can i share it, where to specify it ? RFC7273 requires the RTSP senders to a) use a known clock (e.g. a NTP/PTP, GPS, etc clock) and b) to put the information about this clock (which one it is) and how the media relates to it (i.e. an offset between the clock epoch and the RTP timestamp) into the SDP. If that is given, then you can make use of the RFC7273 feature on the receiver side to get accurate synchronization based on that clock and when the media was captured according to that clock. Otherwise you might still have some other options (e.g. if you know that the senders are synchronized to a specific NTP clock and advertise this in their RTCP packets), but nothing standardized or simple that works without configuration. It completely depends on your setup then. -- Sebastian Dröge, Centricular Ltd · <a href="http://www.centricular.com" rel="noreferrer" target="_blank">http://www.centricular.com</a> _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </blockquote></div> </div>