等高线形状变化规律的研究

Study on the Similarity of Contour Shape

为了准确地从地图上获取地形高程信息,在对等高线形状的变化规律进行深入研究的基础上,首先从理论上论述了等高线形状变化的相似性规律;然后根据该规律研究出了描述等高线相似性传递的2维整体内插模型;最后利用该模型分析了现有的图形内插算法,并提出了基于物理场概念的等高线相似性传递模型。为了验证该模型的应用效果,分别对一模拟数据和一实际等高线数据进行了实验,实验结果表明基于物理场概念的等高线相似性传递模型不受初始等高线形状限制,在初始等高线光滑性较差时也能够有效地获取描述3维地形高程起伏变化规律的等高线信息。

Contour line is a kind of map symbols, with which 3D terrain can be recorded on 2D map. Map users know the elevation of terrain with the change of contour line. The changes of contour line means local change and whole change. The latter is also called shape change, and it contains more information of terrain. There are many studies on local change of contour line, and a lot of achievements have been made, such as curvature analysis, dominant points detection, and so on. There are little studies on whole change of contour line, which leads to some problems related to whole terrain remaining unsolved, After studying on shape change of contour line deeply, the author concludes the similarity rule for shape change of contour lines. It provides a new way to interpolate contour line with two neighboring contour lines, Besides, the methods put forwards in this paper can be used to reconstruct 3D terrain surface with contour data. Experimental results show that the new methods can interpolate contour line effectively.