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

[RC]

On Thu, 7 Jul 2005 10:34:40 +0200
Matthias Wieser <mwieser at gmx.de> wrote:

> Less work for the deinterlacing filter.

In most cases, it's a nominal difference.

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

You'll find that NTSC broadcasts are commonly telecined, also.  Inverse
telecine filters don't have negative side-effects if the content is
not telecined, so it's best to always include it.

> 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?

I was mistaken.  It seems vf_crop does pass the flags other important
information through.

However, if your objective is to save CPU cycles, putting crop before
pullup may be pointless at best, or counter productive at worst.
Disabling direct rendering in pullup will slow things down, not speed
them up.  Though, it should make such a very small difference in either
case I wouldn't bother trying...