> frame(s)!" and also "Skipping frame!" messages.
>
> I have googled a bit, but I cannot understand why is mencoder finding
> so much "duplicate frames".
I had exactly the same problem since upgrading my Distro. But since I
compile MPlayer from source, MPlayer stayed the same. So i figured out
it must be a driver and/or configuration issue.
Mencoder skips or duplicates frames to maintain audio/video
synchronization (it doesn't _find_ them, it _makes_ them!). I also tried
-noskip. That worked, but resulted in A/V drift.
What seemed strange to me was that there were so much skips and
duplicates _directly_ following each other. Clearly, this doesn't make
any sense (if the fps from TV-input don't change, there should only be
occasional skips _or_ occasional duplicates, but never both of them
intermixed). Skips and dups following each other cancel themselves out -
with a delay of just one frame. So all you get is a jerky Video!
> Info: I live in Brasil. Here we use PAL-M, which means NTSC dimensions
> and framerate with PAL color encoding.
>
> The relevant parts of my .mplayer/config :
> tv=driver=v4l2:norm=PAL-M:chanlist=us-cable:alsa=yes:audiorate=32000
This looks like it has something to do with (audio) buffering. I could
verify this by switching off the -tv alsa option: There were no more
excessive skips/dups and no drift - but sound quality was just terrible.
After extensive experimenting I could solve the problem by setting the
ALSA period_size from 1024 to 256. Now i only get 6 skips and 2 dups in
3 minutes of TV-capturing. Also, they don't directly follow each other
anymore (minimum 30 frames distance).
To set period_size, I used the ~/.asoundrc from
http://wiki.ubuntuusers.de/.asoundrc
(I think I just concatenated the "Initialisierung", "Mixing" and the
"OSS" listings). Then I changed period_size in the pcm.dsnooper section
to 256.
Regards,
Alex
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