[Live-devel] Presentation time, multicast and multiple client connections

[Ross Finlayson]

OK, so we’ve established (again!) that your problem is that your server’s presentation times are not properly aligned with ‘wall clock’ time (the time that you’d get by calling “gettimeofday()”).  This is necessary because the periodic RTCP “SR” (“Sender Report”) packets - sent by the server - are used, by receivers, to properly synchronize the stream, and the timestamps in these RTCP “SR” packets are set by calling “gettimeofday()”.  (Note, BTW, that these RTCP “SR” packets are sent frequently, and do *not* necessarily coincide with the connection of new RTSP clients.)

If - using your current scheme - you cannot keep your presentation times aligned with wall clock time, then I suggest computing your presentation times by calling “gettimeofday()” each time - not just at the start of the stream.  Or, if you feel that that’s too expensive, then compute it using “gettimeofday()” something like every 100 frames.


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