On Mon, 4 Feb 2002, Billy Biggs wrote:
> Mark Vojkovich ([EMAIL PROTECTED]):
>
> > On Mon, 4 Feb 2002, Steve Kirkendall wrote:
> >
> > I'd be surprised if a voodoo card could do 2048x2048. It's one of the
> > worst overlay hardware. Doesn't seem to do the correct YUV->RGB
> > colorspace conversion either (ie. not CCIR601).
>
> Arguably we shouldn't be using the 601 transfer functions anyway, we
> should use the ITU-R BT.709 ones instead since CRTs are likely closer to
> the HDTV standard. I'd also add that MPEG2 video actually specifies the
> 709 transfer function (those mmx'ified yuv2rgb routines everywhere are
> usually doing the outdated transfer).
MPEG2 supports many functions, DVD is 601. Everybody's hardware
does 601 except for 3dfx, as far as I can tell. And 3dfx looks like
crap because of it - all washed out. The poor software conversion
routines look bad because they're not clamping to the 16-240 (or whatever
it was) range.
>
> Do you know what conversion they are using?
Not sure, but luma 15 isn't black.
>
> > > the smoothing seems to kick in at 1024x768. This is true for DVD
> > > player programs too, not just my XMMS plugin. But is there some way
> > > I can detect this? DVDs look better when played with filtering in a
> > > 1024x768 screen than they do unfiltered in a 1600x1200 screen.
> >
> > There's no way to detect that. Ideally, DVD's would look best at
> > 720x480 without scaling.
>
> Where best is defined as stretchy. 720x480 at 4:3 or 16:9 isn't
> square pixel so unless you're lucky you always need to scale. :)
Pixels on the monitor don't have to be square unless you're on
a flat panel.
>
> For best as in least artifacts due to bilinear filtering of gamma
> corrected images in nonlinear space I'd have to agree with you also. :)
Better overlay hardware is doing something more sophisticated than
bilinear.
Mark.
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