[MPlayer-users] Sync Problems dumping DVD audio

[Sebastian]

>> 
>> Hi, 
>> 

><snip/>

>> 
>> If the dvd contains more than one audio source (germany and english), >the
>script creates a multi audio avi.
> 
>> This works on 98% of my dvds. 
> 
>> Now sometimes the audiodumps have different sizes, and the resulting >avi 
> will have a out of sync on at least
> one channel. (playback of this dvd folder is fine!) 

>When you are working with multiple video or audio streams, you should
>make sure that they are identical in every way: bitrate, sample rate, etc.

They are of course identical. The problem is that on these particular dvd, there are like 1-2 megabytes missing in one of the audio tracks.

> On some dvds I get away by using:
> 
> mplayer -dvd-device ""$BASE_FOLDER""$DVD_FOLDER"" dvd://"$CHAPTER" -aid
"$AUD1_1" -vo null -cache
> 8192 -ao pcm:waveheader
> 
> for ripping the audio.
> 

>When you do this, you are decompressing the audio. If you decompress
>both audio streams, you should be OK.


As mentioned, it works for 98% of my dvds



> But there are still some that dont work. I tried -mc 1, -mc 0 -forceidx
-noskip(mencoder) and nobps 
> 
> Then I had another search on the web and I found
> 
> mencoder -mc 1 -noskip -forceidx -dvd-device ""$BASE_FOLDER""$DVD_FOLDER""
dvd://"$CHAPTER" -aid
> "$AUD1_1" -ovc copy -oac lavc -lavcopts acodec=ac3:abitrate=192 
> -af pan=2:1.0:1.0:1.0:1.0,volnorm -of mpeg -o temp.mpg

>What you are doing here is re-encoding the audio at 192 kbps. If you do
>this for *both* audio streams, then they will have the same bitrate, and
>in theory you should have no problems.



both resulting mpg files work fine, if you watch them seperatly. File sizes of the two .mpg files are (again) different.



> 
> Now the strange thing: If I let this run for both languages into 
> separate temp.mpg's, the resulting temp.mpg's will be absolutely synced.
> But both have different sizes again, and I cannot rip them.
> 

>When you say that "both have different sizes again", what do you mean?
>Why can't you rip them? What happens when you try?

first of all, both files use the same video material. that means the audio track should be same lenght. which then means if you have a contant bitrate, the two .mpg files should have the same size
if i -dumpaudio both files the resulting dumpfiles are different in size...
which i find strange, because the two .mpg files are synced to the video

> do the mplayer masters have any more idea i can try?
> 

I can only imagine that maybe one of the audio tracks starts a bit later or something. how can I make mplayer/mencoder fill that beginning with zero bytes?