[vlc-devel] VLC 0.8.6 end of support

Marian Ďurkovič md at bts.sk
Wed Sep 3 11:10:00 CEST 2008


On Wed, Sep 03, 2008 at 10:42:32AM +0200, Rémi Denis-Courmont wrote:
> Yeah and VLC should add a fairly constant delay for the clock synchro to
> work. Not something the old RTP code did (nor the new RTP code so far,
> indeed). It would be gullible to believe that the old 100ms check did that.

Yes it did (modulo OS delays). If you don't believe it, put a printf()
into the old RTP/UDP access :-) And most importantly, it ensured
continual timing even in case of lost packet.


> > If you plan to implement "proper jitter calculation" for VLC1.0,
> > you'll just significantly reduce compatibility with zero benefit to the
> user...
> 
> Oh yeah? We have lots of users complaining about VLC excessive input
> delays.

You definitely won't fix that by "proper jitter calculation". Input delay
could not be reduced even in lab environment with zero network jitter,
since the real problem is in the PTS_DELAY hack.

Moreover, when you start computing jitter for every single IP packet
instead of once per PCR, with HDTV streams you'll end up with ~2000
computations per second instead of ~20. We already lack CPU cycles
for h.264 streams, and such waste of CPU will really not help anyone. 


         M.



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