While I would love to 'count coup' on Mark (for probably the first time) I don't think I quite managed it here.
My response was really considering the entire analog vs digital TV system. I hadn't considered just the totally fixed pixel displays. For those I think we've had other discussions here about whether the lack of built-in Gaussian filtering means a bit lower effective resolution. I still consider that an open question.
I think we've also touched on the subject about whether it might be better with projectors to get some of that filtering simply by having them slightly unfocused. And I also point out our eyes will likely provide some of that filtering if we are sitting more than maybe 3 screen heights from the display. It all goes back to whether we can actually see the pixel/raster structure.
As a humorous note, anyone trying to read the "A Pixel is Not a Little Square" paper in Mark's link below should note that you can't click on the title, only on the following little red square. That confused me at first and I thought he had only pointed me at an abstract. ;-)
- Tom Mark Schubin wrote:
Craig Birkmaier wrote:Looks like Tom caught you here Mark.You can't compare apples with oranges. We are talking about Nyquist limited images in both cases - i.e. video.As I pointed out, the edges of the smallest elements of a display violate Nyquist.I refer you to the title of Dr. Alvy Ray Smith's Technical Memo "/A Pixel is /Not/ a Little Square, a Pixel is /Not/ a Little Square, a Pixel is /Not/ a Little Square! (and a Voxel is /Not/ a Little Cube)."/http://alvyray.com/Memos/default.htmThe fact remains that in an analog system of ANY bandwidth, the peak (or trough) of a sine wave is infinitely positionable (though the precision and repeatability could be difficult). In a digital system of ANY number of samples, the position of a white (or black) sample is limited by the number of samples.As a practical matter, low-bandwidth analog spread, high sample numbers, and Nyquist violations make calculations difficult.TTFN, Mark ---------------------------------------------------------------------- You can UNSUBSCRIBE from the OpenDTV list in two ways:- Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org - By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word unsubscribe in the subject line.
-- Tom Barry trbarry@xxxxxxxxxxx Find my resume and video filters at www.trbarry.com ---------------------------------------------------------------------- You can UNSUBSCRIBE from the OpenDTV list in two ways:- Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org
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