Terrain geometric parameter extraction method based on hierarchical elevation cloud atlas

Abstract

The invention relates to a terrain geometric parameter extraction method based on a hierarchical elevation cloud atlas, which comprises terrain classification and recognition, terrain simplification and terrain geometric parameter extraction processes. For a 401*401 DEM grid terrain specified in the digital map of the GeoTIFF format of the ASTER GDEM type, the relative height is first calculated to divide the terrain into five types: the plain, the hill, the low mountain, the middle mountain, and the high mountain through programming; the hierarchical elevation cloud atlas of the specified terrain is obtained through elevation layering and color mapping; the eight neighborhood boundary tracking algorithm is used in image processing to obtain the terrain bottom surface boundary, the bottomsurface area and the center of the bottom surface, and the color representing the maximum elevation interval is identified to obtain the average elevation of the highest area of the terrain; finally,the geometric parameters of the plain, spherical crown, cone and wedge shape of the terrain simplified geometric model are obtained by combining the terrain classification, the calculation of the bottom shape factor and the slope calculation. The invention has the advantages of simple method, small calculation amount, real-time performance and practicality.

Description

technical field [0001] The invention belongs to the fields of geographic information system (GIS) and computer graphics and images, and relates to a classification method of topography and geomorphology and a method for extracting topographic geometric parameters and a simplified model, specifically a method for extracting topographic geometric parameters based on layered elevation cloud images , which can be used for automatic discrimination of terrain types, approximate calculation of radio wave propagation and rapid real-time display of terrain models. Background technique [0002] The digital map based on geographic information system (GIS) is supported by geographic information system and digital mapping system, and its functions and functions are constantly improving with the development of GIS technology and digital mapping system. The specific meaning of a digital map refers to a generalized and ordered collection of cartographic elements and discrete data on a reada...

AI Technical Summary

Problems solved by technology

It can be seen that the existing research results have the following problems: (1) The research only involves special terrain points (such as mountain tops, saddle points), special lines (ridge lines, valley lines, mountain lines, foot lines, defense boundaries) and other local areas. For the recognition of geometric features, there is a lack of research on the recognition, segmentation, simplification, and extraction of geometric parameters of the overall terrain geometry; (2) the research method has a low degree of automation due to some parameters manually set; (3) for the real-time application of terrain , there is no research on the limited range of terrain distance, and it is difficult to guarantee the practicability of the method

Images