分类后栅格数据矢量化中自交多边形处理算法

A Self-intersecting Polygon Processing Algorithm in the Vectorization of Classified Raster Data

分析了导致分类后栅格数据矢量化中多边形自交的数据类型点,并将它们定义为对角结点。给出了自交多边形的定义,提出了一种分类后栅格数据矢量化中自交多边形处理算法。实际数据实验发现,本算法能将所有对角结点处理为只有两个链接方向的数据点,很好地解决了矢量化算法中多边形自交问题。

The data points which cause self-intersecting polygon in the vectorization of classified raster data are firstly analyzed and defined as the diagonal node.An general concept of self-intersecting polygon is given.Further,an algorithm is presented to process the self-intersecting polygon.Tests with real data demonstrate that the algorithm is very effective to handle all diagonal nodes to 2-connected direction points,and there is no self-intersecting polygon in the vector results.A comparative test between the algorithm and the method used in the ENVI software is made to prove that the self-intersecting polygons in the result of ENVI do not appear in the result obtained by the method present in this paper.Therefore the method in this paper is better than that of ENVI.