RFC: Xv field order

[Thomas Hilber]

On Tue, Jun 23, 2009 at 10:19:25PM +0200, Krzysztof Halasa wrote:
> Thomas Hilber <xorg at toh.cx> writes:
> Ah, I didn't know this. Is it supported by the textured video? Overlay
> only?

I haven't tried textured video since a while because this had bad
tearing effects at the time when I started my vga-sync-fields project.
This may have changed meanwhile.

Scaling interlaced material vertically is supported by at least overlay
video on i9xx chips.

Maybe somebody can roughly tell how this scaling feature has been realized
for intel i9xx series hardware? Would be very interesting. I haven't 
found any documentation about that yet.

> > no, my patch collection is for conventional TV - one screen only. 
> > My major concern was not to encounter any field loss. That's why I
> > synchronize field timing dynamically to the stream clock.
> 
> Sure, I OTOH work with non-live data.

right, when playing non-live data VGA output timing needs not to be synced
to an external signal. But for live-TV it's crucial if you don't want to lose
fields/frames.

The more I'm wondering there still does not exist any other solution to that
problem except my vga-sync-fields patch. Even vdpau does still NOT sync
video timing to an external clock source (e.g. PTS dictated by a TV station).

Which means that even vdpau loses/doubles fields/frames when watching
live-TV.

- Thomas