this method first decomposes the skeleton into its meaningful component ( such as branch and loop ) set, then vectorizes each components to simple structure elements ( such as straight line segments and circles ) and finally arrange them into an attributed relation graph 该算法首先将骨架分解为它的有意义分量(如分支和环)集,然后将各分量矢量化为简单的结构基元(如直线段和圆),最后将它们组织到一个属性关系图之中。