My stupid plasma claims to support 24fps, but judders with it (probably does 3:2 internally).
When playing 24fps @ 60Hz, usually 3:2 is applied like this:
A, A, A, B, B, C, C, C, D, D, E, E, E, F, F
This approach produces very visible motion judder. Is there any chance to implement a simple frame blending algo like the following to “upsample” 24fps to 60fps?
A, A, (A+B)/2, B, B, (B+C)/2, C, C, (C+D)/2, D, D, (D+E)/2, E, E, (E+F)/2, F, F
Just to make sure there are no misunderstandings: This is not motion interpolation, instead it’s very simple frame blending. This is (more or less) similar to what madVR and mpv do when activating “smooth motion”. It very nicely removes the 3:2 pulldown judder, resulting in playback which is just as smooth as true native 24fps @ 24Hz playback. Of course it’s not a perfect solution, it does introduce a small amount of blur and ghosting, but these problems are almost invisible, and the motion smoothness improvement is dramatic.
(Ideally, the frame blending should be done in linear light, but I expect that to require too high GPU power, so simple blending in gamma light would be more than fine.)
If there’s any chance to add support for something like this, I’d be quite happy. If this gets added, we might need an additional option like “my TV sucks at 24fps playback”, to make sure OSMC/Kodi don’t ever activate native 24Hz output. Instead Kodi should auto switch to 60Hz (if auto refresh rate adjustment is enabled) and activate this smooth motion algorithm.
Edit: FernetMenta already implemented something similar for Kodi, but only for OpenGL, and his approach is probably more complicated than my very simple suggestion above: