Say I make a big animated title sequence in Blender, and I want to overlay it on clips in Kdenlive. Is this possible? I can make a movie of the titles, but not sure how to over lay, so the kdenlive clips show through. Is chromakey possible?

I can do the reverse, that is export a movie from Kdenlive, then work with it entirely in Blender, except I'm having problems dealing with audio in Blender..

Hi.

Currently you can only achieve transparency with images (png, non animated gif). Chroma key transparency is not yet implemented in the MLT video framework...

regards

Just to clarify (because am a bit of a newbie) does this mean selecting a colour in a video as transparency? Much like blue/green screen effects?

I did a Google search, but most of the results were rubbish about US patents!

Yes, that's something like blue screen effect, but it is currently not implemented in MLT

I have just been reading up on, and exploring, MLT, and it appears that Chroma-key transparency is supported.

The 'vmfx' module has a 'chroma' filters which takes an RGB value 'key' (e.g. "0x800000" for Red) and an

'variance' (0..1) and sets the alpha to '0' wherever the choma matches the key to within the variance.

There is also a 'chroma_hold' filter which seems to turn all colours outside of the variance to grey.

How hard would be to add this filter to kdenlive?