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

On 2007-05-27 22:58:32 +0200, Marcin Zajączkowski <[email protected]> wrote:
> 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)

I would like to add that for a track with an *introduction* there is an
audio track as well and mplayer reports the same info for it.
After tcextract/mplex run mplayer's output is still the same.


Marcin


> 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
> 
> 
>