  We propose technology to enable a new medium of expression, where video
elements can be looped, merged, and triggered, interactively. Like audio, video
is easy to sample from the real world but hard to segment into clean reusable
elements. Reusing a video clip means non-linear editing and compositing with
novel footage. The new context dictates how carefully a clip must be prepared,
so our end-to-end approach enables previewing and easy iteration.
  We convert static-camera videos into loopable sequences, synthesizing them in
response to simple end-user requests. This is hard because a) users want
essentially semantic-level control over the synthesized video content, and b)
automatic loop-finding is brittle and leaves users limited opportunity to work
through problems. We propose a human-in-the-loop system where adding effort
gives the user progressively more creative control. Artists help us evaluate
how our trigger interfaces can be used for authoring of videos and
video-performances.
