RFC: Xv field order

[Ville Syrjälä]

On Tue, Jun 23, 2009 at 10:10:18PM +0200, Krzysztof Halasa wrote:
> Ville Syrjälä <syrjala at sci.fi> writes:
> 
> >> Come on, playback of interlaced video only makes sense with vertically
> >> unscaled display.
> >
> > Not true if you can scale the fields independently.
> 
> Well, correct. Is something (hardware, drivers) capable of doing that?

Any hardware with a decent texture unit (or scaler which writes the
results to the framebuffer) should be enough. Also some hardware has
video overlays which can do it too (OMAP3 is one example).

I don't know if any Xorg driver can do it, but DirectFB's matrox
driver supports field based scaling. It uses the texture unit.

> It would mostly make sense with small reduction (like 576->480), right?

The scaling ratio should be irrelevant. The fields are basically
independent pictures so you can scale them how much you like.

-- 
Ville Syrjälä
syrjala at sci.fi
http://www.sci.fi/~syrjala/