说明：  本程序主要实现图像的骨架化。细化和骨架化操作是把区域的面宽度缩到最小，即单像素宽度，也就是把物体变细，直到现最小的像点连通性。
(The main procedures of the skeleton of the image. Refinement and skeleton operation the face width of the region is reduced to a minimum, i.e., a single pixel width, which is the object thinner, until now the smallest image point connectivity.)