Sorry about the late reply.
This was about synchronicity problems in a decoder mpeg2-stream that
only turn up when encoding.

> From: Andrew Stevens <[EMAIL PROTECTED]>
> The Reason for effects like this are basically, that a DTV audio
MPEG-2
> stream may have "gaps" of varying length in the audio. If you simply 
> decode as a stream the gaps disappear and sync disappears.

This is the problem.

> Another common Problem is problems caused by varying pull-down in the
> original. If you have some 3:2 pulldown material (say some Ads) 
> where one field of a frame is repeated at playback time simply 
> decoding frame-by-frame and re-encoding will affect timing.

This is not the case, I work with PAL material.

> Basically, its pretty complex and to get  transcoding to work right 
> all the time you need a carefully written transcode decoder that 
> communicates the pulldown information to the video encoder and silence
> pads the audio stream being sent to the audio encoder at the right  
> places.

I guess this means "sorry, you lost".
A pity.
I solved this particular problem by hacking the file apart with a tool I
wrote some months ago and encoded every part by itself. That way the
problem does not become visible. Between the sections half a second or
so becomes lost but between episodes this is not serious.

I have sync problems with all of thos streams but they are usually
fixable because they are constant.
I just hope that this particular problem will stay rare.

Thanks, for clearing that one up.


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