基于改进的LOS算法实现对复杂地形场景的可视域分析  

An improved line-of-sight method for visibility analysis in 3D complex landscapes

作　　者：刘骝[1] 张立强[1] 张良[2] 张兴明[1] 杨玲[1] 

机构地区：[1]北京师范大学遥感科学国家重点实验室 [2]北京建筑工程学院测绘与城市空间信息学院

出　　处：《中国科学：信息科学》2011年第6期675-685,共11页Scientia Sinica(Informationis)

基　　金：国家自然科学基金(批准号:60736007;60972128);国家重点基础研究发展计划(批准号:2007CB714403)资助项目

摘　　要：基于视线(line of sight,LOS)原理,结合地形高程信息,文中提出了一种运算效率较高的改进LOS算法,用来解决复杂场景下的可视性分析问题.该算法不仅采用计算目标点与视点的几何关系来判定可视域,更重要的是利用了地形高程信息来对目标点的可视域进行判断,将部分目标点的可视域判断条件简化为其高程与指定高程的比较,从而提高了地形可视性分析的计算效率.该方法不仅可以应用在三维森林场景的可视域分析中,还可应用在城市环境的分析中.实验证明,文中提出的方法在计算效率和精度上优于传统的可视性方法.This paper presents an effcient method for implementing visibility analysis on complex landscapes based on an improved LOS （line of sight） algorithm. The method determines the viewshed by analyzing the geometric relationship between the target points and viewpoint. It differentiates the visibility of the target points by the elevation information. Eventually the visual results related to the given viewpoint are rendered on three-dimensional landscapes. The visibility of some target points is computed by comparing their elevations with the viewpoint’s height, thus is able to enhance the effciency of the visibility analysis. This method can not only be applied in the visibility analysis of forest scenes, but also used in the analysis of the urban environment. Experiments show that the proposed method results in high effciency and precision.

关 键 词：LOS 可视域 复杂地形场景 可视渗透性 

分 类 号：P208[天文地球—地图制图学与地理信息工程] TP391.41[天文地球—测绘科学与技术]