[Live-devel] rtp over rtsp: timestamps in RTCP SR

[Gajdosik Johannes]

On Wed, 10 Aug 2016 07:28:41 -0700
Ross Finlayson <finlayson at live555.com> wrote:

> Absolutely not!
> 
> LIVE555 programmers should never have to deal with RTP timestamps directly.  Our software automatically uses RTCP to convert presentation times to RTP timestamps (when transmitting) and back to presentation times (when receiving).  Presentation times are all that you need to think about.
> 
> Therefore, whatever problem you (think you may) have, please describe it again, without using the term “timestamp” (at all!).  Don’t submit a ‘patch’.  Please just describe your problem.  And, once again, don’t mention the word “timestamp” at all.

Ok.
How to reproduce: The misbehaviour only happens with rtp over rtsp. rtp over UDP is ok.
1) receive a stream from liveMedia and observe presentationTime in YourSink::afterGettingFrame(...)
The values of presentationTime increase nicely as they should. Continue observing.
2) During observation make a new connection with another instance of your client in order to receive the same stream a second time. You will notice the values of presentationTime in 1) to jump.

So the receiving process of the first client is influenced by the connection of the second client.

This behaviour is fixed in by previous patch, which I hope will be useful for all experiencing a similar problem.

Yours,
Johannes Gajdosik