[linux-dvb] Re: Problems using mplex

[ma.hoff@bigfoot.com]

> No, that can happen. I have to check the routines that try to
> determine the time offset between audio and video when I have time.
> Just give a low number for the offset.
> 
> Marcus

Dear Marcus,

is it possible to integrate a check for VPTS-APTS Difference for every GOP or every packet that's written out in mplex ?
This would easily solve the problem of VPTS-APTS Drifts that still seem to occur...

An example: I recorded about 1 hour video with the 0.8.2 driver and VDR 0.7.1. So this is split up into two files 001.vdr and 002.vdr.
Using mplex to remux both files gives us the following results:
001.vdr	VPTS-APTS = 219ms
002.vdr	VPTS-APTS = 315ms
Cutting the thing a little bit with vdr gives us values of VPTS-APTS = 219ms at the beginning and towards the end something about VPTS-APTS = 387 ms (and even worse)
And using windows mediaplayer to play back mplexed mpegs also reveals that at the end audio and video aren't in sync anymore - seems logical, because only the 219ms are corrected, so at the end there are still 160 ms left, which are quite noticeable. 

So, is it possible to make mplex check VPTS-APTS synchronity on a per GOP or per packet basis ?

Regards, Martin.





-- 
Info:
To unsubscribe send a mail to listar@linuxtv.org with "unsubscribe linux-dvb" as subject.