1. A method for detecting object motion within a sequence of images representing a scene, comprising: (a) selecting a plurality of images from said sequence of images; (b) applying a two dimensional transformation to said plurality of images to align stationery regions of said plurality of images and identify a misaligned region of said plurality of images; (c) computing a parallax rigidity constraint that identifies a parallax motion component of the misaligned region; and (d) processing said parallax motion component to detect a moving object within the scene.