What you’re still not apparently understanding here is that RTP timestamps are 
used only as a shortcut to transfer the presentation time from the sender to 
the receiver.  I.e.
        (sender)        presentation time -> RTP timestamp in RTP packets -> 
presentation time  (receiver)
In other words, the presentation time is *all* that you have.  Seeing the RTP 
timestamp as well would give you ***no more information*** (because the RTP 
timestamp is used only to compute the presentation time, and the resolution of 
the presentation time is the same as that of the RTP timestamp).

In other words, the *only* ’time' information that you have about each incoming 
frame is the presentation time.

If, for whatever reason, the presentation time (as generated by the sender, and 
received by the receiver) does not advance sufficiently smoothly for your 
taste, then that’s a problem for you (the receiver) to deal with.  You don’t 
know for sure why the sender might be behaving this way (remember that a proper 
RTP receiver needs to be able to work with *any* compliant RTP sender, not just 
the server that you’re using right now) - but simply ignoring the effect of the 
sender’s RTCP “Sender Reports” (which is what you’d effectively be doing if you 
were to ignore the computed presentation times and look only at the RTP 
timestamps) is never the right thing to be doing.  It is precisely these 
presentation times that tell you when to ‘present’ each frame of media, and 
also let you synchronize separate audio and video streams (if you have them).

And if, for whatever reason, your RTP sender (server) is not compliant, then 
you'll need to fix it.


> Would you kindly reconsider exposing the RTP timestamp in RTPSource?

No, for the reason that I stated.

(This will be my (and your) last posting on this topic.)


Ross Finlayson
Live Networks, Inc.
http://www.live555.com/


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