[mythtv-users] Archiving Shows to DVD

[Cory Papenfuss]

> The best approach is to add code to avidemux2 (and probably 
> mplex/replex/transcode/whatever) to handle varying A/V sync within the 
> stream.  Since most players (i.e. xine, MPlayer, and even Myth) can do so, it 
> should be possible--the hard part is finding someone willing to make the time 
> to make the changes.  (I'll admit I'm being selfish with my time since DISH 
> provides a workaround for me.)
>
 	I've inquired about that on with avideumx developers.  It's pretty 
low on the list.  I actually think that something like gopchop of gopdit 
is a better place to start.  It will cut the streams in place without 
de/remuxing.  It just needs to get some bugs worked out, and figure out 
how to set timestamps after a cut.

 	The problem is a matter of heirarchy AIUI.  The synchronization 
between the Video and Audio streams that's causing the problem is at the 
ProgramStream (PS) level.  That's where the PTS/DTS lives.  Once it's 
demuxed, that information is gone.  That's why it needs to be done in 
place.

 	A more fundamental question would be how should something like 
gopchop deal with cuts.  Allow for 4-5 minute "magic" timeshifts in the 
resulting stream?  Change the timestamp of all packets after the first 
cut?  Should it also allow for inserting the VOBU padding so another 
replex isn't necessary?

 	ProjectX is pretty close to the only one I've found that does it. 
It appears to try to fix timestamps and has a dizzing array of options to 
do so.  It's intended for manipulating DVB streams (with multiple 
programs), so it's fairly complicated.  Too bad it uses the J-language... 
much larger than it would need to be for a CLI utility.

-Cory

-- 

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* Cory Papenfuss                                                        *
* Electrical Engineering candidate Ph.D. graduate student               *
* Virginia Polytechnic Institute and State University                   *
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