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[vdr] Re: Cutting problems?



Wolfgang Fritz wrote:
> 
> Steffen Koch wrote:
> > On Tue, 04 Feb 2003 18:21:47 +0100, Wolfgang Fritz wrote:
> >
> >
> >>I can understand that ds.jar detects the cuts by the jumps in the
> >>timecode, but what I do not understand is that it has to insert audio
> >>frames at the cuts for several hundred milliseconds to maintain A/V sync.
> >>
> >>If I replay the resulting DVD image file with mplayer, I can notice the
> >>short pauses in the audio at the cuts, but the video distortions are gone.
> >>
> >>It seems to me as if video and audio are cutted at different times and
> >>some audio is "lost" at the cuts.
> >>Has anybody seen these effects too?
> >
> > This is correct... Since audio is early (smaller buffer reqd.) around
> > 200 - 400 ms and vdr is writing them together and not time corrected to
> > the hdd, audio is early too in the file. VDR is then using the video
> > pts as reference for cutting.
> >
> So times in marks.vdr are correct for the video stream?

Actually VDR doesn't look at any PTS or whatever when cutting. It simply
takes the I-frame at the starting point together with whatever audio
packets might be in there. This is a very simple approach which must
work since replaying an MPEG2 stream must be able to start at any time
from the next available I-frame.

Klaus
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_______________________________________________________________

Klaus Schmidinger                       Phone: +49-8635-6989-10
CadSoft Computer GmbH                   Fax:   +49-8635-6989-40
Hofmark 2                               Email:   kls@cadsoft.de
D-84568 Pleiskirchen, Germany           URL:     www.cadsoft.de
_______________________________________________________________


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