[MPlayer-users] Re: Re: introducing DVD-to-DivX approach that fixes A/V sync problems

[Rich Felker]

On Mon, Jul 11, 2005 at 06:19:12PM -0500, Christopher J. Bottaro wrote:
> Rich Felker wrote:
> 
> > On Sat, Jul 09, 2005 at 01:23:52PM -0500, Christopher J. Bottaro wrote:
> >> Rich Felker wrote:
> >> 
> >> >> Is there any trick that can be used to avoid a/v sync problems
> >> >> with vbr audio using mencoder (mencoder or lame options)?
> >> > 
> >> > Yes, several.
> >> <snip>
> >> > 2. Dump the audio with mplayer -ao pcm and encode it with external
> >> >    lame. Then run mencoder with -audiofile lame_output.mp3 -oac copy.
> >> <snip>
> >> 
> >> I tried that and the A/V gradually desyncs over time on my portable media
> >> device.  These are the commands I used:
> >> 
> >> mplayer dvd://1 -chapter 1-2 -vo null -ao pcm
> >> 
> >> lame -b 96 --resample 44.1 audiodump.wav audiodump.mp3
> >> 
> >> mencoder dvd://1 -chapter 1-2 -o test.avi -ovc xvid -xvidencopts
> >> bitrate=196:max_bframes=0 -audiofile audiodump.mp3 -oac copy -vf
> >> scale=160:128 -ofps 14000/1001
> >                      ^^^^^
> > was that supposed to be 24000?
> 
> No.  The device can only do 15 FPS max, but I noticed that it slows down a
> little, so I opted for 14 FPS.

Hmm, better to use 12 if the source video is 24 fps (or 12.5 if the
source is 25 fps). Anything but exactly half will look very
choppy/bad.

Rich

p.s. of course 12 means 12000/1001 :)