满足方向一致性的等高线提取算法

Algorithm for extracting contour lines with consistent direction

黄土高原地区有地形复杂、局部特征突变较多的特点,因此要准确描述地形,进行地形特征分析和建立土壤侵蚀模型难度较大,而现有等高线提取算法不论在运算时间还是求解精度上均很难得到较为理想的结果。从保持等高线方向一致性的角度出发,对等高线传播算法进行了改进,并在此基础上,给出了方向一致性等高线的拓扑关系表示方法。通过对黄土高原罗玉沟流域的数据进行实验,结果表明了改进的算法执行效率较原算法有显著提高,而且能够提取出方向一致性等高线,为后续的地形特征分析和土壤侵蚀模型的研究奠定基础。

Due to the complexity of the landscape in the loess plateau region,having more features mutation,it is very difficult to accurately describe the terrain,carry out the terrain feature analysis and establish the soil erosion model.And the existing contour extraction algorithm could not meet the requirements,whether in time consumption or calculation accuracy.So the algorithm of contour lines spreading abroad on the aspect of maintaining the direction of contour lines is improved.On basis of that,the representation of topological relations of the contour groups is given.Experiments on the data of the Luoyugou Watershed on the loess plateau prove that the algorithm is more efficient than the original one,and the contour lines with the consistent direction can be extracted,which lays the foundation for terrain feature analysis and soil erosion model establishment.