Head Tracking Using Shapes and Adaptive Color Histograms

A new method is presented for tracking a person's head in real-time.The head is shaped as an ellipse, and the adaptively modified RGB colorhistogram is used to represent the tracked object (head). The method iscomposed of two parts. First, a robust nonparametric technique, calledmean shift algorithm, is adopted for histogram matching to estimate thehead's location in the current frame. Second, a local search isperformed after histogram matching to maximize the normalized gradientmagnitude around the boundary of the elliptical head, so that a moreaccurate location and the best scale size of the head can be obtained.The method is demonstrated to be a real-time tracker and robust toclutter, scale variation, occlusion, rotation and camera motion, forseveral test sequences.