[MPlayer-users] Trouble with dvd sync

[Rich Felker]

On Wed, Sep 28, 2005 at 11:10:04AM -0600, Dark Shadow wrote:
> My vcr just died and I have no money for a replacement so I am trying to
> record shows on my computer but I am having trouble with av sync going out.
> So far I am happy with the video quality as it is way better then my vcr was
> even though it is not perfect. Please help me as I am missing alot of shows
> every day this does not work
> 
> 
> Here is what I have so far
> 
> /usr/bin/amixer sset Aux2 100
> /usr/bin/nice -n 0 /usr/local/bin/mencoder\
> tv:// -tv
> driver=v4l2:device=/dev/video0:norm=ntsc:fps=30:input=2:width=352:height=480\

This could be the problem, since ntsc is not 30 fps but 30000/1001 fps.

> :alsa:adevice=hw.0,0:audiorate=48000:amode=1\
> -oac lavc -ovc lavc\
> -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9800:\
> vbitrate=1800:keyint=15:acodec=ac3:abitrate=192:aspect=4/3:ilme:ildct\
> -mc 0 -noskip\
> -quiet\
> -of mpeg\
> -o $1.mpg\

If you're trying to make dvd-compatible mpeg you should use the right
-mpegopts for that.

Also I don't know how to ensure a/v sync with -mc 0 and -noskip unless
your sound card's timer is perfect. :( But clearly skipping or
duplicating any frames with interlaced video is horribly wrong. :( You
might see if ffmpeg can do a better job, somehow adjusting the
captured audio to fit instead. Or, if you can get the tv card itself
to capture the audio, that might have better sync.

Another option is to get a card that can capture directly as mpeg2, so
that the card handles the sync.

Rich