说明：  由于图像的最短路径能准确地表示目标的边缘，显示强边 缘特征的像素有较低的局部代价值。因此，局部代价函数由下 面变化的边缘特征构造
(Because the image of the shortest path to the target accurately the edge pixel edge features show strong local generation of a lower value. Thus, local changes in the cost function by the following structural characteristics of the edge)