A dynamic segmentation of moving targets based on an active contour is presented in this paper.Utilizing that the active contour is a B spline curve

the way for design the num ber of controlpoints is given. Meanwhile

the motion of B spline controlpoints is derived from the im age data

so that the active contourcan track the edge of moving object automatically and dynamic segmentation is performed. Experimental results are also included to show the feasibility of the newly presented method.