[MPlayer-users] Two-passes encoding - What happens exactly?

[Fabio S.]

> > I read though on this mailing-list that two-passes encoding improve
> > quality. I don't disagree of course but I would like to know how it
> > happens. On the man page, the only thing I read is "vpass activates
> > two pass mode etc ...".
...
> > As I don't fully understand what happens during the two-passes
> > encoding, I don't know if I have to recopy all the parameters. I
> > explain: -vf is for filtering thus once filtering is done it should
> > not be filtered a second time except, I suppose, if I recrop and
> > rescale. But post-processing? And software scaler (though I read in
> > man page that software scaler had to be used with the -zoom option)?
...
> > My question is. Do I have to recopy all the options? Sorry if it is
> > stupid.

It is the same for me: it would be nice if somebody would explain exactly
(in a qualitative way) what happens during two pass encoding, how to use
it for (as you said: do we need to rewrite all options?) and when we can
use it (is it possible to use it for capturing from the tv?)

Fabio