Is it possible to use AviSynth difference overlay to see live changes?

[ELinder]

I'm not sure how to ask this, and have even less idea of how to go about it. I'm still trying to go thru the QTGMC parameters and see what they do and how to best use them. However I have to say most of the time I can't see a big difference when I'm changing things in AvsPmod.

I use a difference layer blending mode in Photoshop and Resolve to see how things compare, align things, etc, so I started to look into AviSynth's overlay function. I only see a way to use existing clips. Is it possible to use Overlay in difference mode to overlay 2 clips created in the same AviSynth script? For example, can I open a video file, apply 2 different instances of QTGMC in parallel on the open clip, and overlay those together to see only where they are different? It would be a sort of interactive way of highlighting what different parameters and setting actually change.

Erich

[Feedbucket]

I was just recently looking at something similar myself. This might be helpful: http://avisynth.nl/index.php/Subtract

A = QTGMC(Preset="Slow")
B = QTGMC(preset="Fast")
Subtract(A, B).Levels(65, 1, 255-64, 0, 255, coring=false)

You can also view clips side by side with StackHorizontal()

A = QTGMC(Preset="Slow")
B = QTGMC(preset="Fast")
StackHorizontal(A, B)

I think the things you'll want to pay attention to are noise reduction and edge detection.

[ELinder]

Aha! Defining the different versions as A and B and then using the result is exactly what I was wondering if possible. I'll have to give this a try tomorrow.
Thanks!

Erich

[themaster1]

The simplest way use avspmod, load a script in 2 or more tabs then hit preview and switch tabs. That's how i do

[ELinder]

I've tried Overlay mode, Subtract mode, tabs, and I find Feedbucket's suggestion of stacking the versions next to each other easiest to see the differences.

Erich