[MPlayer-users] Re: [-] Crop before deinterlacing OK?

[Matthias Wieser]

Am Donnerstag, 7. Juli 2005 03:08 schrieb RC:
> On Wed, 6 Jul 2005 11:08:17 +0200
>
> Matthias Wieser <mwieser at gmx.de> wrote:
> > Is there any disadvantage in doing crop before deinterlacing?
>
> Is there any advantage in doing crop before deinterlacing?

Less work for the deinterlacing filter.

> As long as 
> you stick to multiples of 4 you should be fine.

For normal PAL and NTSC broadcasts, but not for telecined NTSC movies, am 
I right?

> Those of us using NTSC need to inverse telecine first

I thought you only need to inverse teleine when capturing NTSC movies. 
Normal NTSC TV broadcasts can be deinterlaced with pp=[md|lb...], right?

>, and those
> filters (eg. pullup) really do need to come before croping (or
> anything else).

Mplayer HTML documentation says: "[...]you must crop vertically by 
multiples of four or else the inverse-telecine filter will not have 
proper data." Which informations included in the TV signal are lost when 
cropping? I think DVD has something like a soft-telecine flag but TV?

My questions are related to Kalva, a GUI application for tv capturing.
I can only test PAL, so I need your advice for NTSC countries.

Thanks,
  Matthias