Segmentation And Tracking Of Moving Object In Complex Background

In the field of image processing, the segmentation and tracking of moving object in video sequences is a hot research topic in recent years. Various of segmentation methods can be used according to different situations of moving objects and its background.In this paper,we propose a new simple and effective system ofsegmentation and tracking of moving object in a stationary complexbackground. In this system,we combine the merits of motion detectionbased on blockmatching algorithm and the object segmentation based on active contour(snake), and get a satisfied result through the testing of a serious of different video pictures.Following are detailed steps of this system:In the segmentation section,we use three successive frames to detect the motion infomation of the pictures,by using blockmatching algorithm in two successive frames twice,we can get two pictures composed of motion blocks of the moving object,then we find out the common motion blocks of the two pictures,experiments prove these blocks approximately compose the moving object.After getting the motion blocks,we calculate the center of these blocks as the center of the moving object,thus we can use the center point as the origin,construct n straight linesjoining the boundry of the image and the center.On each line,we can find out a proper point near the object contour according to some criteria, then we use these n points as the initial points of the snake and let the snake converge on the object contour,thus finish the segmentation of the moving object.In tracking section,we still adopt the snake to converge on the object contour by improving the energy functions,in the tracking frame,initial points are acquired by calculating the average inter-frame motion vector of the block,because all snaxels have approximately thesame motion vector as the moving object is proposed to be rigid and have no salient deformation.Experiments prove that the system can be used to segment and track the single moving rigid object with comparatively large inter-frame vector,and the result is good enough especially to those objects with smooth contours.