Dissolve

Joins two frames in sequence. The input 'second' is appended to the input 'first' with an optional overlap.

The overlap used is the smallest of the three values 'overlap parameter', 'first clip length', 'second clip length'.

The output frame type will be the same as the first clip while the first clip is being used (before and during the overlap). After the overlap the frame type will be the same as the second clip.

Note to self: If the frame sizes are different we are in trouble. We could clip the second to the first, but what happens after the overlap?