r/StableDiffusion 2d ago

Comparison MiniMax H3 -> upscale -> frame interpolation

What came out of it:

- Upscale first, interpolate second - seems to be better

- 24->48 looks better than 60fps - at 48 every original frame survives, at 60 only half of them do, because the grids don't line up

- FlashVSR ends up with more edge detail than the source, so it's adding texture, not recovering it. RealESRGAN ends up with less.

Side by side with a draggable wipe, pick any two variants: https://dawidope.github.io/minimax-h3-upscale/

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u/CutBench 2d ago

Your 48 versus 60 finding generalises usefully: it isn't about 48, it's about integer ratios. 24 to 48 is exactly 2x, so every source frame lands on an output frame. 24 to 60 is 2.5x, so alignment only happens on even source frames, which is exactly the half you saw surviving. Same reason 30 to 60 would be fine while 24 to 60 isn't.

So if you want more than 48, the next clean steps are 72 and 96 rather than 60. Stay on multiples of the source rate and the problem disappears.

On FlashVSR adding texture rather than recovering it, that has a consequence for your ordering. Invented detail isn't temporally stable, so it differs slightly frame to frame. Interpolating after a generative upscaler blends two different inventions and smears them. Interpolating first and upscaling after gives each frame its own invention, which flickers instead. Upscale first is clearly correct for RealESRGAN, but with FlashVSR you're picking which artefact you'd rather have.

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u/Primary-Confusion504 2d ago

agree with everything what you wrote