基于规则格网DEM的等高线提取算法的优化与实现

An improvement and realization of contour extraction algorithm based on RGD

随着DEM数据获取质量的日渐提高,利用规则格网DEM准确快速地提取等高线已经成为等高线自动绘制及DEM精度评估的重要方法之一。本文在传统算法的基础上,提出了遍历状态值、中心点符号法、"视点"等概念,分别对格网遍历原则、等高线走向二义性问题及等高线方向一致性处理等方面进行了优化,并使用C++语言在VC++6.0集成开发环境中实现了该算法。

With an increasingly high advancement of the quality of DEM data, a correct and rapid contour extraction from Regular Digital Elevation Model has become an important way in the field of automatic drafting for contour, as well as in DEM precision evaluation. In this paper, based on the traditional algorithms, we reorganize the data structure of the grid, and put forward some concepts, such as Visited Value, Sign of the Middle Point, Perspective, etc. Those concepts are involved to advance precision and efficiency of the redisplay algorithm by dealing with some problems, such as principles of traveling through grids, contour tracing direction, keeping the consistency of contour direction, etc.