Re: Problem with VOBU in files ripped by dvd::rip

On 2007-05-27 0:50:39 +0200, Jörn Reder wrote:
> Marcin Zajączkowski wrote:
> 
>> I can transcode it to be in a "proper" format (and then it works fine), 
>> but I don't want to lose quality (source and destination formats are VOB 
>> and should be compatible).
>> Could it be a problem with dvd::rip that ripped files have problem with 
>> VOBU and aren't directly usable by dvdauthor?
> 
> You can try to demux and mux the VOB files to get a proper MPEG2 program
> stream which is compatible with dvdauthor.
> 
> Something like this:
> 
>   % cat *.vob | tcextract -a 1 -x ac3 -t vob > audio.ac3
>   % cat *.vob | tcextract -x mpeg2 -t vob > video.m2v
>   % mplex -f 8 -o av.mpg video.m2v audio.ac3

It worked fine (I only had to change "-a 1" to "-a 0") for an one
chapter with an introduction. But I have a strange situation with an
audio with chapters with "normal" content (this could be a problem with
tcextract).

mplex reports problem with audio file:

[marcinz@bolger 002-C005]$ mplex -f 8 -o av.mpg video.m2v audio.ac3
   INFO: [mplex] mplex version 1.8.0 (2.2.4 $Date: 2005/08/28 17:50:54 $)
   INFO: [mplex] File video.m2v looks like an MPEG Video stream.
**ERROR: [mplex] File audio.ac3 unrecogniseable!
**ERROR: [mplex] Unrecogniseable file(s)... exiting.


It's a problem with an audio file generated by txectract.
mplayer for *VOB* file shows:

==========================================================================
Opening audio decoder: [liba52] AC3 decoding with liba52
Using SSE optimized IMDCT transform
Using MMX optimized resampler
AUDIO: 48000 Hz, 2 ch, s16le, 192.0 kbit/12.50% (ratio: 24000->192000)
Selected audio codec: [a52] afm: liba52 (AC3-liba52)
==========================================================================
AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample)


A generated file with *audio* has a few megabytes, but mplayer shows
only errors:

libavformat file format detected.
LAVF_header: av_find_stream_info() failed
libavformat file format detected.
LAVF_header: av_find_stream_info() failed


Maybe you have some idea what could be wrong?



> You can use FIFO's instead of the video.m2v and audio.ac3 files and 
> start the processes in parallel for better performance. I attached a 
> small (quick and dirty) shell script for this purpose. It grabs all 
> *.vob files in the current working directory and remuxes them into a 
> single .mpg file.
> 
> Pass filename, audio track number and codec as command line options:
> 
>   % cd /path/to/vob/files
>   % remux-vob /tmp/test.mpg 0 ac3
> 
> Hope this helps,

Thanks, script is very nice. Works fine with a track where tcextract
generates good file with an audio :)


Regards
Marcin