基于等高线形状分析的LIDAR建筑物提取

Building Extraction from LIDAR Data Based on Shape Analysis of Contours

基于等高线形状分析,提出了一种新的LIDAR(机载激光雷达)建筑物提取方法.首先利用LIDAR数据生成DSM(数字地面模型)等高线,然后根据等高线形状特征参数,从DSM等高线中提取由建筑物点云形成的等高线(建筑物等高线).最后,根据拓扑关系简化建筑物等高线,再利用建筑物轮廓线相互垂直或平行的特点,对建筑物等高线进行规则化,提取建筑物.实验结果表明,即使在地形起伏的情况下,该方法仍可提取出形状复杂的建筑物,准确率达80%以上.

A new method for building extraction, without the need for DTM （digital terrain model） advance extraction, was proposed based on LIDAR （light detection and ranging） data and the shape analysis of contours. In this algorithm, firstly, the initial segmentation of DSM （ digital surface model） contours is carried out based on the closure of a contour and the area enclosed by the contour, and the initial contours of buildings are acquired. These buildings are consisted of closed contours expressing building points and vegetable points and have a certain area. Secondly, after smoothing those initial contours, they are segmented to building contours and non-building contours based on dimension surveying and shape characteristics of the contours, such as rectangle tolerance and circle tolerance. Finally, the building contours predigested by the topological relation are served as the outlines of buildings and normalized based on the vertical or parallel characteristics of building outlines. In a test on an undulated region, buildings＇ contours were extracted from DSM contours and regularized. To validate the test results, an overlay of extracted buildings＇ outlines and an aerial image was checked. The result shows that the proposed method has an accuracy up to 80% and can effectively extract big and independent buildings in undulated regions.