Avisynth: Asharping the optimal avi v4 script?
 

Hii guys, I'm a thankful user of the avi scripts made by Dialhot. They
work great.

Last night, I was playing around with asharp. I found that if I replace
the Lanczosresizer with Bicubicresizer in the avi v4 script, and add the line

asharp(1.5,2,0.2, hqbf=true)

right after the resize, I get a sharper image than with lanczos, and with the testclip i made of 800 frames it was 0,3 MB smaller than the v4 script too!

Especially the "hqbf" is great in my eyes, because it doesn't sharpen the edges of block-noise often found in avi sources, so the result is less noisy also.

What do you guys think about this?

As a rule of thumb, sharpening is usually used before resizing the video.
Due to the simple fact that a lot of detail is lost after the resizing. So I think it would be better to use the ASharp line right before the BicubicResize line. But, I'll try your ASharp setting both before and after the resizing (not at the same time of course :wink: ) and compare the results.

Why not :mrgreen: ?

Watch out as asharp(1.5,2,0.2, hqbf=true)

.... does plain the picture very much!
3 already should be the limit ... as this is the threshold of sharpening, means which will be sharpend and blurred. The lower the threshold gets, the more the sharpen moves to the edges and blurs the other parts, therefore Hairs, skins etc.

And as Otimal Script already does spatial/temporalcleaning in the further lines, this value 2 should be usied with caution.

Inc, you're right (of course) :D

I've tested a bit and changed the line to:

asharp(1.7, 3, 0.15, hqbf=true)

Looks better now, with less blurring in the center of the image.

I'm also considering of kicking out TemporalSoften, maybe replace it with a FluxSmooth or another spatio/temporal cleaning filter.

It's gonna be a long night... :)

Do not replace temporalsoften (temporal only) with a spatio-temporal filter.
The spatial dimension is already well managed by undot, and C3D is already a spatio-temporal.

Try temporalcleaner if you want.

Allright, changed the asharp to

asharp(1.3, 3.8, 0.18, hqbf=true) and placed it before the resize.

Furthermore I replaced undot + temporalsoften with fluxsmooth(7,7)

This gives better image quality in my eyes. It takes a bit longer to encode though... btw, the file-size is more or less the same as the v4 script in my testclip (have to do more testing to be sure).

Yeah, unfortunally fluxsmooth is quite slow.
Be carreful also : have a close look to the "moving paint" problem. That is when too much spatial filtering is done and the color starts to become unatural. It's like if all the colored area were "painting" in movement.

Thnx Dialhot, I'll look into it and tweak around with the settings...