保持地貌特征的数字高程模型生成方法研究

Method for Generating DEM Geomorphologic Feature

由于数字高程模型中的地貌信息与精度对于分布式水文模拟与分析具有重要影响,提出了一种应用数学形态方法从数字化等高线数据内插生成栅格数字高程模型的新方法.该方法通过对栅格化后的等高线单元进行数学形态学的膨胀处理,形成等高线单元的骨架单元,分析了骨架单元与主要地貌特征的对应关系,对骨架单元进行插值.然后基于骨架单元的膨胀路径,对剩余单元进行线性插值,完成整个数字高程模型的生成.通过实验分析表明:该方法生成的DEM不仅满足单元高程的测量精度,而且正确表达了等高线数据中所蕴含的地貌特征信息,能够更好地满足分布式水文模拟中地貌特征提取与水文分析的要求.

The Geomorphological information and precision in DEM have significant effects on distributed hydrology imitation and analysis. A new algorithm of generating DEM from digitalized contour using mathematical morphology was developed. The algorithm produced the skeleton cell of the rasterized contour through morphologic dilation after the contour was con verted to DEM cell. The interpolation of skeleton cell was carried out after analysing the correspondence of it and the main geomorphologic features. Then the total DEM was generated by interpolated the remnant cells based on the expansion route. The experiment reuslt shows that the developed method generate not only a high metric precision DEM, but also a good terrain representation of geomorphological feature implied in contour data, and provide higher quality data for the further extraction of geomorphologic feature and hydrology analysis.