Non-linear video editing tool/API?

Question

Can anyone recommend a good library that would enable me to write an application that can blend multiple input videos into one output video (for example into a split screen).

I don't care about the programming language (C, C++, Java, Ruby and Python are fine).

The only one I found is GStreamer with the non-linear plugins. But I can't find documentation on how to use the non-linear plugins. So I'd be glad to use an alternative.

Answer 1

You could try Avisynth.

Answer 2

MainConcept is the leader http://www.mainconcept.com/site/

Not surprisingly, Adobe are their major customer. http://www.mainconcept.com/site/company-3/partners-21749/customers-by-industry-21763.html