[MPlayer-dev-eng] ok to add new vf?

[D Richard Felker III]

On Wed, Jul 26, 2000 at 11:18:05PM +0200, Arpi wrote:
> Hi,
> 
> > The normal solution would be to use the sw scaler to scale down. But
> > suppose you have to scale a 640x480 movie down to 640x240. Assuming
> > your codec outputs a planar colorspace such as yv12, the vertical
> > chroma resolution after scalind down will be 120. You've thrown away
> > half your chroma samples for no reason, since 240 lines of chroma
> > would still fit perfectly fine.
> > 
> > Here's where -vop halfpack comes in. It converts planar yuv input to
> > packed yuv (yuy2) output, halving the vertical luma resolution but
> > keeping all the original chroma samples.
> 
> hmm. what about just calling the 422p -> yuy2 converter, with doubled Y
> stride value and half height?
> 
> that code is already mmx etc optimized and is part of postproc/*

That would be nice, except it will just drop every other line of luma,
which will look horrible.

Rich