Chroma key and actor costumes

Chroma key is a post-production compositing technique: a uniformly colored background, usually green or blue, is removed and replaced with another image. Chroma key itself does not mean an actor wears a special suit that is later turned into a visual effect. Actors in marker-covered suits are usually performing motion capture or performance capture, a separate technology that records movement or acting for animating a digital character. The methods can be combined in a film, but they are distinct processes.