I am working on a stop-motion animation which was shot outside. So there is a lot of flickering in lighting, which is okay. But I need to erase a rig that holds up a puppet. The back template is at one lighting and does not match the front layer throughout.
I was wondering is there an effect or expression that samples the exposure or HLS from the front layer and can apply it to the back layer, so the flickering affect is translated to the back template? So let say we start with a uniform exposure in which the front and back match. Then as the front changes, we add or subtract the difference to the HLS or exposure of the back template.
If you're open to third-party effects, GenArts Sapphire has a compound effect called S_FlickerMatch which does exactly what you describe: looks for flicker in a second source clip and attempts to match it in the first.
If you want to dive into an expression that will drive an automated adjustment, you could start with sampleImage [link] and rgbToHsl [link]. This should be doable, but it may be quite a bit of work to tweak to look completely natural.
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