Rotate and Scale & Video Quality

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Here is a link to related previous discussion:

Keyframes in action - slideshow. Also featuring overlay HTML/WebVfx

Very nice, but you can see what is called a “moire effect” on some of the slides, which is that shimmering from animating fine details. I have read that you can reduce this problem by adding a tiny amount of blur or un-sharpening (Sharpen filter, Amount < 50%). It is not clear whether to put this blur/sharpen filter this before or after the Size and Position. I think it goes before, but that does run much slower than placing it after, which will probably soften the result too much.

My suggestion was to use Sharpen, Amount < 50% before the Rotate & Scale or Size and Position.

I am having trouble to reproduce as bad a case as yours with my photos. Mine tend to be lower res (~4000x3000) and denoised a little via JPEG. Do you care to make one of your pics available for me and others to experiment?

I looking into libasvfilter zoom pan. It uses libswscale, which is a simple 2D scaler. MLT uses libswscale for inherent scaling, but Rotate & Scale and Size and Position are using an affine transform. Might be related to that