[FFmpeg-devel] Frame blending filter

[Thilo Borgmann]

Hi,

> I'm trying to make slomos smoother, e.g. interpolating 25fps to 50fps to have
> a smooth 50% slomo when the resulting 50 fps is played back at 25 fps. My
> understanding is that no filter for that kind of thing exists currently as
> part of ffmpeg. AFAIK ffmpeg just duplicates frames when increasing frame
> rate or allows framerate to be interpreted differently using the setPTS
> filter.
> 
> As a "cheap" alternative to real frame interpolation (which would probably
> involve motion vectors, I suppose btw. are these exposed in public API at the
> moment?) I'm thinking about playing around with a frame blending filter, i.e.
> one that computes frames as a weighted average between a adjacent frames in
> the original material. Does anyone have a recommendation, which existing
> filter would be a good starting point to get into the topic?

Sounds like an extended overlay filter to support alpha channel.

Don't know if it is already capable of that though...

-Thilo