[MPlayer-users] Sync Problems dumping DVD audio

Nicolas George nicolas.george at normalesup.org
Wed Dec 29 16:13:29 CET 2010


L'octidi 8 nivôse, an CCXIX, Sebastian a écrit :
> I use mplayer/mencoder to make my avi's from my dvds. 
> 
> Here is what my script basically does: (I'll delete all the blah blah)
> 
> #Extract audio streams
> mplayer -dvd-device ""$BASE_FOLDER""$DVD_FOLDER"" dvd://"$CHAPTER" -aid "$AUD1_1" -dumpaudio -dumpfile 1st.ac3
> .
> .
> mplayer -dvd-device ""$BASE_FOLDER""$DVD_FOLDER"" dvd://"$CHAPTER" -dumpvideo -dumpfile vid.m2v

Even with one audio stream, that will desync sometimes.

VOBs inside DVDs are made of several MPEG programs concatenated, the
stitching is usually at the chapter marks. At the end of these programs,
there may be a few extraneous video frames or audio samples, usually no mor
than about half a second but sometimes up to a couple of seconds.

If the audio and the video are decoded together, the decoder can ensure sync
them by adding silence or black frames. If the audio and video are decoded
separately, that is not possible.

If you want to transcode a DVD without risking a desync, you _have_ to
transcode the video and the audio together.

And please fix your mailer so that it does not create a new thread each time
you reply to a mail.

Regards,

-- 
  Nicolas George
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/mplayer-users/attachments/20101229/0acca39b/attachment.pgp>


More information about the MPlayer-users mailing list