1. A method for detecting people by a surveillance system, the method comprising: identifying a foreground contour shape within a scene and a track of the foreground contour shape from at least two frames in a video file; determining features of the foreground contour shape within the scene and the track of the foreground contour shape; and classifying at least a portion of the foreground contour shape using a shape feature and the track of the foreground contour shape to determine whether the foreground contour shape matches a person reference model.