[Live-devel] RTP/RTCP startup behaviuor

[Marian Durkovic]

Hi Ross & all,

   during startup phase of separate audio/video ESs transmitted over RTP 
users might see the following behaviour:

No RTCP SR received yet:
- stream plays fine for couple of seconds 
RTCP SR received for the first ES:
- video (or audio) stops for couple of seconds (the other ES plays)
RTCP SR received for the second ES:
- both ESs resume playing 

  The problem is caused by the fact, that after first RTCP SR is received,
the PresentationTimes for the two ESs are based on completely different
time bases.

  What is the solution to this problem? Wouldn't it be possible for
liveMedia library to wait until RTCP SRs are received for all ESs and
only then change the time bases for all ESs at the same time? 

   I think It has no sense to do it earlier, since unless we have seen 
RTCP SRs for all ESs, we're not able to perform intermedia synchronization 
anyway - and the current behaviour is causing very bad user experience.


	Thanks & kind regards,

		M.

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----   Marian Durkovic                       network  manager         ----
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