基于像元有向边的栅格数据扫描线矢量化方法  

Approach of Vectorization for Raster Data Based on Pixel Directed Edge

作　　者：苏程[1] 周祖煜 倪广翼[1] 俞伟斌[1] 黄智才[1] 章孝灿[1] 

机构地区：[1]浙江大学空间信息技术研究所,杭州310027 [2]杭州大地科技开发公司,杭州310012

出　　处：《计算机辅助设计与图形学学报》2011年第7期1139-1147,1158,共10页Journal of Computer-Aided Design & Computer Graphics

基　　金：浙江省科技计划基金资助项目(2006C33056)

摘　　要：为了将海量栅格数据的面状信息快速矢量化,提出一种使用扫描线技术顺序遍历栅格数据、使用链表技术组织像元有向边动态构造区域边界、使用隐含射线法判断孤岛归属的栅格数据矢量化方法.该方法以单个像元为着眼点,利用栅格数据中所隐含的空间信息直接将栅格图斑转换成矢量区域;全部矢量化过程只需对栅格数据遍历一次,不产生任何中间数据,也不需要构建多边形拓扑关系等二次操作,是栅格数据矢量化的一步式解决方案.实验结果表明,文中方法具有较高的效率且易于实现.Proposed a new approach of vectorization for raster data in order to extract the vector region information from raster data efficiently,which traverses the raster data sequentially using a scan-line method,organizes the Pixel Directed Edge using the linked list technique to constitute region boundaries dynamically,and determines the ownership of isolated island using the hidden ray method.This approach could convert a raster spot into a vector region directly by making use of the spatial information implied in raster data,such as the arrangement of pixels and the feature of Pixel Directed Edge we defined.It could obtain the complete vector information of a region by traversing the raster data only once without any intermediate data and some other operations like constructing topological relationship of polygons.Our method turns to be a one-step vectorization solution for raster spots.Experimental results show that the approach is efficient and easy to implement.

关 键 词：栅格 矢量化 像元有向边 扫描线 拓扑 

分 类 号：TP392[自动化与计算机技术—计算机应用技术]