[MPlayer-dev-eng] [RFC] rc2

Matthias Hopf mat at mshopf.de
Thu Apr 12 12:51:47 CEST 2007

On Apr 11, 07 21:44:41 +0200, Nico Sabbi wrote:
> >I don't think that is all. An ac3 frame has a length of 32ms for 48k
> >audio, and I found (per-file constant) offsets of -200 to 200ms with the
> >native TS demuxer.
> there's usually an initial preload in broadcast transmissions
> (audio transmitted somewhat ahead of time wrt to video), that is:
> "near" packet N there's a video packet with Vpts(N) and an audio 
> packet with Apts(N)=Vpts(N)-K.
> Mplayer will initially play them as if they corresponded to the same
> pts, but after few seconds the sync stabilizes.

In that case mencoder somehow doesn't respect these. The offset I was
taking about was all in transcoded files (to XVid/avi) with -oac copy.

> IIUC  lavf seems to discard the initial packets corresponding to the 
> pre-loaded stream

Sounds reasonable given the symptoms.



Matthias Hopf <mhopf at suse.de>      __        __   __
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