采用3维Douglas-Peucker算法的等高线综合

Generalization of Contour Lines Using Three Dimension Douglas-Peucker Algorithm

在数字环境下进行等高线综合是制图综合领域中的热点问题。将3维Douglas-Peucker算法应用于等高线综合,是从真3维的角度提取等高线上的特征点。首先根据等高线上高程点的空间分布特征,提出采用空间线规则排序方法组织空间点;引入了全局孤独指数解决综合过程中等高线之间的空间跳跃问题;然后通过空间内插引绘综合后DEM的等高线,从而实现等高线的自动综合。初步实验表明,采用3维Douglas-Peucker算法的等高线综合,从全局上保持了主要地貌形态并抑制了破碎的微地貌特征,具有良好的综合质量和制图效果。

The generalization of contour lines is an active issue in the field of cartographic generalization. A new method for the generalization of the contour lines was introduced based on the automated generalization of the corresponding DEM using three dimensional Douglas-Peucker （3DDP） algorithm, then spatial interpolation techniques were used to derive the final simple contour lines. According to the spatial distribution of 3D points along the contour lines, two technologies including line-wise sort technology for simplifying the operation and the improved universal loneliness index for the spatial break between different contours were designed to develop the application of 3DDP algorithm. The preliminary experiments showed that the generalization of contour lines using 3DDP algorithm could maintain the macro relief form while depressed the micro geo-morphological vibration with satisfied quality both in generalization and cartography.