基于机载LiDAR点云和建筑物轮廓线构建DSM的方法

Method for constructing DSM based on building contour line and airborne LiDAR data

为了获取高精度的数字表面模型(digital surface model,DSM),提出了利用离散的三维激光点云和建筑物轮廓线构建DSM的方法。首先,利用不规则三角网(triangulated irregular network,TIN)渐进滤波算法对激光点云进行预处理,得到地面点和非地面点;然后,基于高程纹理提取非地面点中的建筑物脚点,根据脚点的深度影像图,利用Canny算子提取建筑物边缘,用方位角聚类规则法对建筑物边缘规则化;最后,采用提取的离散地面点数据和建筑物轮廓矢量线构建DSM。采用柳州地区的一组机载LiDAR数据对该方法进行了实验验证,结果表明,通过该方法构建的DSM,建筑物的边缘信息比较精确。

In order to obtain high aeeuracy DSM data, the authors put forward the method for construction of DSM by using irregular ground points ground points and non - ground and contour vector line of buildings points through adaptive TIN filter First, the point clouds are separated into method. Second, the building points are separated from the non - ground points according to the height texture. Then, the edges of buildings are extracted by Canny operator based on the depth images of the building which have been gray - quantized; afterwards, the azimuth clustering Comparative Law is used to regulate the building edge. Finally, the DSM couht be huilt by using irregular ground data and contour vector line of buildings. An experiment was performed with a group of LiDAR data obtained in Liuzhou. The results show that the information of buildings＇ edges can be more aceurate in the DSM constructed by the proposed method in this paper.