Generalization of digital elevation models for military passability maps development

Abstract. This paper presents the methodology of the digital elevation model (DEM) generalization which aims to reduce the generation time of the military passability maps. The generalization is based on the local standard deviations of slopes on the analyzed area. It assumes that in areas, where the diversification of relief is low, the elevation points should be reduced, which may significantly increase the efficiency of the process of the military passability maps development. The generalization was performed on the LIDAR (Light Detection and Ranging) elevation data, which can be obtained with no charges from the Polish Head Office of Geodesy and Cartography. The data are in 1 m resolution and in an ASCII grid file, which contains all coordinates (X, Y and H) of elevation points. The conducted research shows that the modification of parameters used in the generalization process (shape and size of primary fields, number of classes and standard deviation threshold) influences the degree of generalization of obtained results. What is more, the generalized DEMs allowed to reduce the processing time of the passability maps by about 3.5 times compared to the non-generalized model. The parameters used for generalization can be adjusted by the user to individual needs which makes the tool universal.