[mythtv-users] Objective IVTV quality measurement instructions
Jay R. Ashworth
jra at baylink.com
Sat Aug 14 11:31:25 EDT 2004
On Sat, Aug 14, 2004 at 10:55:42AM -0400, Cory Papenfuss wrote:
> > *Ghod*, I love grad students.
> ... that would rather work on fun stuff like mythtv than their
> research, no less... :)
Well, Hell, Cory; if you can't find a way to make your MythTV *be* part
of your research, you're not much of a damned grad student, are you? ;-)
> > I'll be trying this out in the next day or three, Cory; thanks. Does
> > the image have any other useful test patterns on it? I align a fair
> > number of TV's and projectors in a year...
> It's just a work in progress. I collected a few more test images.
> I don't really believe the colorbars' accuracy (not sure if you can
> even *generate* a true colorbar pattern with COTS hardware like a
> DVD player). There's a B&W gamma pattern, and a simple aspect-ratio
> geometry pattern. I was mainly after the resolution test pattern.
You can't guarantee linearity -- you're actually *testing linearity* --
but the only think I don't know that you can do reliabily is PLUGE
bards; I don't know if the bits go to 7.5IRE or 0. It's the usual
problem in digital video gear; consumer gear usually opts for 7.5, but
th einconsistencey causes apparent gamma errors between program
> Shortly after I announced this a few months back, someone asked for
> a PAL version. I think I tried to generate it and put it up there. All
> of this comes with a HUGE YMMV disclaimer... :)
Remember, on DVD, the only different is the frame rate and the
resolution; the *player* does the color.
> Actually, for my own resolution tests, I hacked up a modeline and
> had the computer generate the test signal at 1800x480. A DVD player at
> 720x480 is not too bad, though.
We'll see in a couple days.
Jay R. Ashworth jra at baylink.com
Designer Baylink RFC 2100
Ashworth & Associates The Things I Think '87 e24
St Petersburg FL USA http://baylink.pitas.com +1 727 647 1274
"You know: I'm a fan of photosynthesis as much as the next guy,
but if God merely wanted us to smell the flowers, he wouldn't
have invented a 3GHz microprocessor and a 3D graphics board."
-- Luke Girardi
More information about the mythtv-users