[MPlayer-users] How to create a wav file with silence with MPlayer

[Giacomo Comes]

On Tue, Oct 04, 2005 at 10:48:27AM -0400, Giacomo Comes wrote:
> On Tue, Oct 04, 2005 at 11:06:16AM +0200, Reimar Döffinger wrote:
> > Hi,
> > On Mon, Oct 03, 2005 at 11:01:29PM -0400, Rich Felker wrote:
> > > It's probably a good thing that it doesn't work, instead of exhibiting
> > > random behavior that you won't be able to rely on in the future.
> > 
> > I'd like to say that I am responsible for the change in behaviour of
> > -frames. I asked about comments but got no really conclusive reply.
> > The problem with the old implementation was that the behaviour was
> > basically random, which created problems for people using e.g. -vf png.
> > Now it (should) always could the number of frames output.
> > Suggestions for improvement are still welcome though.
> 
> Well, I was complaining because now -vf png does not work as before.
> (see http://mplayerhq.hu/pipermail/mplayer-users/2005-October/055924.html)
> and you see a BIG difference if you use -vf framestep=I.
> My requirement is to render all keyframes in the first n frames.
> n is known, the number of key frames in general in unknown and can
> change from file to file.
> 
> For me the best would be to have the possibility to choose between 
> the two behaviour, but I can adapt my script to the new one if
> that is how it is going to work in the future.

I forgot to mention that with the new behaviour of -frames the
following command does not work anymore:

mplayer -vo null -vc dummy -ao null -frames 1 -v file.mpg

mplayer never stops ant play the whole file.
In order to make it work again you need to take out -vc dummy:

mplayer -vo null -ao null -frames 1 -v file.mpg

Giacomo