[MEncoder-users] bad sync when recording DVB

[Stefan Sassenberg]

Benjamin Adler wrote:
> Hello List!
> 
> I'm trying to use mencoder to record german TV with my technotrend PCI DVB-C
> card. The problem is that audio and video are never really in good sync. The
> time difference is not the same for every recording, but it often is far too
> much to be usable.
> 
> 
> 
> # mencoder dvb://ZDF -o testnormal2.mpg -of mpeg -mpegopts
> 'format=dvd:tsaf:drop:vaspect=16/9' -vf harddup -ovc copy -oac copy -endpos
> 00:00:10
> MEncoder 1.0pre8-4.1.1 (C) 2000-2006 MPlayer Team
...
> Video stream: 4604.194 kbit/s  (575524 B/s)  size: 5778263 bytes  10.040
> secs  243 frames
> 
> Audio stream:  256.000 kbit/s  (32000 B/s)  size: 320000 bytes  10.000 secs
> 
> 
> 
> I've tried many things to correct this:
> 
>  - specify -mc 10, as recommended on some websites
>  - use a different muxer:
>    -of lavf -lavfopts
> 'format=mpg:i_certify_that_my_video_stream_does_not_use_b_frames' -vf
> harddup -ovc copy -oac copy
> 
> But I just can't get an mpeg with correct a/v-sync. I've put up a 7mb sample
> video (with quite good, but not perfect sync) recorded with the above
> command at http://politbuero.dyndns.org/sample.mpg. The output was:
> 
> Do you have any ideas? If this ever works, the next step is to convert it to
> x264, so I'm not afraid of additional steps/conversions.
> 
> Thanks for your help!
> Ben
> 
Hallo Ben,

as far as I see it, it is disadvised to use "-ovc copy -oac copy" for 
that purpose. Instead you can use the dumpstream functionality.

Which brings us to the next question: How can I create a well synced 
mpeg file from such a dump file? Maybe that answeres your question, too.

Stefan