[MPlayer-users] Re: slightly confused by mencoder output

[Matthias Wieser]

Am Donnerstag, 15. September 2005 21:51 schrieb Rich Felker:
> On Thu, Sep 15, 2005 at 11:43:58AM +0200, Matthias Wieser wrote:
> > I thought that both interlaced video and 2:2 can get out of phase. At
> > least I have seen normal interlaced video where bob made motions
> > appear like forth-back-forth-back-... (kernel bug...).
>
> That's not out of phase, but reversed field dominance. And it's not a
> kernel bug (unless the field dominance is mislabelled), just
> misinterpretation by the app which is assuming top-field-first.

The saa7134 driver had a bug which made the fields appear in the wrong 
order. I don't know anymore which kernel version it was but I'm sure you 
will find some entry for that in the changelogs.

> Out of phase capture of 2:2 pulldown:
>  A A B B C C D D E E F F G G
>
> (lines indicate how the fields are paired in captured pseudo-frames)
>
> Reversed field dominance (video or post-pulldown film):
>  B A D C F E H G J I (video)
>  B A C B D C E D F E (film)

Thanks, I confused reversed field dominance with out of phase.
So the worst thing would be an out of phase capture of 2:2 pulldown with 
reversed field dominance ;-)