Microsoft Xbox 720 Video Capture Detailed
With the feature, players can tell the console to record footage during what Polygon’s source calls “magic moments.” Basically, if the player gets a headshot, scores a goal/touchdown in a sports game, or unlocks an achievement (some of the examples given) then the console will record the footage leading up to that event. It should be noted, though, that this feature only works with next-gen games.
http://gamerant.com/microsoft-next-gen-xbox-achievements-video-capture/
