特征点与骨架线约束的DEM简化

Generalization of DEM restrained by feature points and terrain skeleton lines

针对基于特征的地形简化方法不能很好的同时顾及特征点和骨架线的问题,提出了一种特征点与骨架线约束下的数字高程模型简化方法,在选取重要的地形特征点构建简化不规则三角网的同时,利用地形骨架线对简化过程中不规则三角网的生长实施约束。从等高线生成、高程精度、地形形态描述指标和地形骨架线保持程度4个方面,与广受关注的特征点方法、新近提出的复合方法进行对比。实验结果表明,本文提出的方法在各个方面均较显著地优于前两种方法,能够在地形简化过程中更全面、更大程度的保留初始地形的形态。

According to the fact that the generalization of digital elevation models based on feature points can not keep terrain skeleton lines,this paper reports a new method which reconstructs the gridbased elevation data to form a triangular irregular network that keeps the important feature points and skeleton lines.In order to evaluate the new method,it is compared with the feature point-based method and the drainage-constrained compound method in terms of contouring,elevation accuracy,terrain parameters and skeleton matching measurement.The results show that the new method outperforms the feature point-based and the compound methods.