HDTV rescaling vs. Avisynth resizing

[Marin85]

Hi,

I am wondering, can the upscaling and downscaling procedures, commonly used in modern HDTV technology, be simulated accurately by Avisynth, say by some of the built-in resizing filters or by external filters?

[PhrostByte]

I don't think HDTVs do anything special when resizing. Avisynth should be able to match or better them, especially if you include things like NNEDI and LimitedSharpenFaster. As far as "simulated accurately", I doubt you could end up with pixel-perfect identical results.

Some HDTVs also do motion interpolation for playing at higher FPS, which can make things appear sharper. MVTools can do something similar.

[laserfan]

Even if the answer is Yes, the question would be "but why bother" if your HDTV does a good job presently. Some years ago I spent an awful lot of time trying to make a DVD (yes, std def) look better w/Avisynth & filters than my video setup was producing. Trying to upsize it such that it looked "better". After hours/days/weeks at this I finally decided it just wasn't worth the effort, indeed I couldn't even say with conviction that it looked one iota better.

But it was a good Learning experience because now when I have a specific video Problem, which Avisynth and its filters can help to resolve, I know how to do it (recently I fixed a nast jitter problem with Stab I think it was.

[Didée]

can the upscaling and downscaling procedures, commonly used in modern HDTV technology, be simulated accurately by Avisynth
Precise answer: You probably could, but you actually can't.

(Whatever is done by a HDTV could be done by Avisynth, too. The problem is that you don't know what exactly a HDTV set is doing.)