MLT is an open source multimedia framework, designed and developed for
television broadcasting.  It provides a toolkit for broadcasters, video
editors, media players, transcoders, web streamers and many more types
of applications.  The functionality of the system is provided via an
assortment of ready to use tools, XML authoring components, and an
extensible plug-in based API.

This requires libdv and ffmpeg.
libquicktime is optional but recommended, since it will be needed
by kdenlive anyway.
Additional optional dependencies are ladspa_sdk and frei0r.

Optional:
By default PYTHON=yes for openshot.