Patent ID: 6870945

Claim:
A method for tracking an object among a plurality of image frames, the object moving relative to a background, wherein portions of the background that are initially hidden, become observable during tracking, the method comprising the steps of: defining a background mask for each one frame among a plurality of image frames, including a current image frame, the background mask of a given image frame comprising background pixels, the background pixels of the given image frame being within observable portions of the background for the given image frame; deriving a background model from the plurality of image frames, wherein for each image frame, background pixels within an observable portion of the background are identified, and wherein an identified background pixel is included in the background model only after being observable within the background for at least three consecutive image frames; classifying each one pixel of the current image frame as being a background pixel or a foreground pixel based on the background model, the current image frame, and at least one of a prior image frame and a subsequent image frame; defining a foreground mask for the current image frame as being pixels not in the background mask for said current image frame; and identifying the object as being the pixels within the foreground mask for the current image frame.