[mythtv-users] A few comments / ideas on editing MPEG2 material, asynch AV streams and mastering to DVD

[Steve Adeff]

On Wednesday 02 November 2005 12:16, Darksoul wrote:
>  Hi list,
>
> I hope that ideas and comments from a Windoze user are accepted here in the
> list. <ggg>
>
> I´ve been following the discussions within the user list for a long time.
> Unfortunately my PVR USB2.0 is not very well supported under linux (in
> other words: It doesn´t run under MythTV). So I´m stuck to WinXP with my
> PVR :-|
>
> There have been a lot of e-mails exchanged on this list in regard to post
> processing MPEG2 captures and getting async audio under certain
> circumstances. Esp. unstable analogue signals (bad receiption of analogue
> TV or captures from old VHS tapes) often cause dropped frames / corrupted
> frames within the MPEG2 streams captured using the PVR type of cards. The
> same seems to be true for some DVB-X recordings.
>
> To me it seems that the problems begin once you start using AVIDemux for
> editing your MPEG2 captures. Sometimes peoples are getting async audio with
> their final MPEGs.
>
> I´ve seen comments that demuxing your MPEG2 stream breaks the sync. From my
> experiences this is only partially true. At least under Windows there is a
> tool called Cuttermaran which is able to handle dropped frames / corupted
> MPEG captures even if the MPEG stream is demuxed.
>

avidemux has a known issue with mpeg audio syncing. the author, mean, is 
looking into a better way to process mpegs to eliminate this problem.

as for the processing that cutterman seems to do, it does not seem any 
different than what ProjectX does, which is Java and already runs in linux 
perfectly (because it is Java).

Also, there is someone currently working on a mpeg processing thread for the 
backend that can be run on recorded mpegs to do these fixes within MythTV 
during/after recording.

Steve