Patent ID: 7864980

Claim:
A method for a video motion anomaly detector for processing video images to detect an event of interest, comprising the steps of: receiving, by the video motion anomaly detector, a video signal representing the video images to be processed; extracting, by the video motion anomaly detector, at least one point feature from the video signal; tracking, by the video motion anomaly detector, the position and movement of the at least one point feature within the video images to generate a corresponding at least one track, each of said at least one track representing a corresponding point feature in terms of its position and its velocity within each of the video images; using, by the video motion anomaly detector, an iterative learning process to derive a normal pattern of behavior for each position within the video images in terms of observed incidences of point feature velocity at said each position, wherein the learning process accumulates data representing the behavior of the track(s) over a period of time in a four-dimensional histogram, said four dimensions representing x-position, y-position, x-velocity and y-velocity, of the track(s) within the video images; comparing, by the video motion anomaly detector, present behavior of a track at a certain position within the video images to the respective derived normal pattern of behavior at the certain position in terms of observed point feature velocity at the certain position, wherein the comparison process classifies a track as normal according to a comparison of the frequency of occupation of a histogram cell representing a corresponding position and velocity within the video images with an occupancy threshold; and in response to the present behavior falling outside the normal pattern of behavior in terms of observed point feature velocity at the certain position, the video motion anomaly detector generates an alarm signal.