[FFmpeg-devel] Frame blending filter

[Stefano Sabatini]

On date Friday 2011-05-20 12:36:57 +0200, Robert Krüger encoded:
> 
> 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?

You can find blending utils in overlay, exporting them in a separate
file may be a good idea. Then you may need some form of buffering
depending on the framerate that you want to achieve, maybe you can get
some idea from the fps filter in the soc repo (one of the few never
integrated).

And of course if you plan to integrate the filter into FFmpeg I'll be
glad to help.

> Thanks very much,
-- 
FFmpeg = Freak and Fascinating Murdering Portable Enchanting Gospel