HOLD THAT THOUGHT...

> Almost all of the settop DVD players I've looked at use very ugly
> scaling.  Not quite as bad as nearest neighbor, but you can definitely
> see jagged edges and moire effects that can be alleviated with better
> algorithms.  Using mplayer with software scaling produces visibly better
> output than my settop player.  Of course, it's visible to me, but nobody
> ever seems to notice it. :)

I think you're talking apples and oranges.  Scaling from a 8??x480p source
DVD to 768x480i (I think I'm correct on the horizontal), or maybe 1280x720p,
or maybe 1920x1080i is different than just line doubling a few lines to make
720p go to 768p.  The DVD set top box has to scale and possibly de-interlace
at the same time.  Additionally, not all DVDs have the same resolution.
What if you insert a VCD?  What about a SVCD?  Because of all those
variables, plastic (read cheap) set top box manufacturers rely on cheap but
feature filled scalers/de-interlacers.  HDTV monitors, on the other hand,
have the advantage of specification.  Needing to only support a few input
resolutions, and having a discrete output resolution.

Additionally, don't just assume that scaling more than once automatically
equals bad picture quality.  I know in theory it's not good, but some of the
BEST broadcast quality scalers out there right now will scale a signal more
than once.  For instance, the Gennum VXP scaler will take any
resolution/framing in, scale and de-interlace if necessary to 1920x1080p/60,
and then re-scale and re-interlace if necessary to whatever output you want.
You might say it would be better to only process once, maybe you're right,
but then again, maybe you haven't seen the VXP in action...

-Oscilated



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