Rotoscoping, also sometimes called segmentation, involves tracing objects in a scene to extract or enhance them. Rotoscoping applications allow the user to create a spline, generated through various points and handles, to define an object. The spline is then animated, each point along the curve containing its own animation properties. Artists can spend many hours rotoscoping an object depending on its complexity.
Lytro has written Nuke plugins that use Light Field data to draw splines and automatically propagate those shapes throughout a sequence, reducing rotoscoping work.