Action Surface Filtering Basics

Filtering Basics in Action, covering Linear, Anisotropic, and Elliptical Weighted Average (EWA) Filtering algorithms in Action.


Linear: when there is no animation, integer-based animation only
Anisotropic: when there are heavily rotated surfaces in your scene
EWA: when you there is scaling, tracking, stabilizing, anything with lots of sub pixel animation


“I see juniors and even some mids get wrong.” Haha. It’s cool man, we ALL get this wrong.

I’ll start using anisotropic now; I always thought that EWA was the goto for heavy x/y rotation.

Thank you for the video.


Its this kinda stuff that made me wish stuff was labeled for what it should be used for, not for what it was. :slight_smile:


There’s that old-by-now FXPHD you did going over this that I think ultimately made me too lazy to memorize the proper use of them instinctually. I’d always have to Refer Back To My Notes. Thanks for the refresher! :slight_smile:


Jambo! On the 1st of Tha Month no less!!!

“I see juniors and even some midgets wrong.” Haha.
Been working too long I guess…

4 posts were split to a new topic: Blend Modes Hacks

Hey @randy how do these relate to the filtering options we have in the Timeline resize node? I was always curious why we have one set of filtering option there and a completely different set in action. thanks for the video, good stuff.

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That’s a good question @TimC. I suspect that the timeline resizes are different than the Action ones because Action is a 3D environment and has to take textured polygons into consideration, whereas, the Timeline doesn’t. Or does it? On the surface they do do similar things, but, under the hood there’s probaby a good reason for it.

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…or that filtering would change based on the transformation matrix per-automatique to always give the best result (as an option).

The ones like Lanczos and Gaussian?

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I often use this system to cleanup:

stabilize in action
sequential paint
negate the stabilize
comp this cleanup back over the plate

But the grain/image goes soft. I’ve got the action surface rendering with EWA on both ends, so what am I missing?


It’s always going to introduce some softening. I’m sure you are denoising. A little sharpen in the middle via L_Ash is helpful as well. And either Adding the grain back in or regraining if the original grain is broken.

The Surface Filtering is less about keeping surfaces sharp. It’s more about making a patch/track/translation/surface with no b.s. pixels that you can post process easily.

If you look carefully, stabilizing set to nearest/or linear introduces a digital gate weave as the pixels move approach and leave integers.


ooh never used L_Ash - thanks for the tip! :slight_smile:


I just did a perspective grid stabilize using Anisotropic paint and then Unstabilize with anisotropic and there was no loss in detail and no blurriness. In Difference matte boosting to 10,000 there was no difference between before and after!!! So from now on, I will always use Anisotropic for Perspective grid stab unstab procedure.

TRY ANISOTROPIC next time. With perspective grid it works great!!

one option for 1 point xy stabilizing: the Desktop Stabilizer with Oversampling turned on should help maintain grain detail.


Not in front of the box at the moment but I seem to recall that if your viewport is set to live or the other your image will display soft but not affect the render.