[mythtv-users] VDPAU High qualty scaling

[Christopher Kerr]

On Sun, Aug 15, 2010 at 3:42 AM, Dave Badia <dbadia at gmail.com> wrote:
>>  It will, of course, make no difference for HD videos.
>
> This comment surprised me.  If have my output set to 1080i and I'm
> watching a 720p show, doesn't scaling take place before being output?

I'm going to assume you meant a 1080p output, as using VDPAU and
outputting an interlaced mode is both difficult and self defeating.

The answer, of course, is yes, but scaling from 720p to 1080p is a LOT
harder to notice than scaling from SD resolutions, and since the
difference in scaling quality is small, you've gone from having
scaling artifacts that are hard to detect to scaling artifacts which
are slightly harder to detect. In other words, close enough to no
difference as makes no odds.

Note that a 1080p picture has about 5 times as many pixels as SD PAL
(720x576). It only has about 2 time as many pixels as 720p. That's a
heck of a lot less interpolation to do.

- Chris