利用LMedS算法提取规则建筑物顶部面片

Extraction of the Building's Top Patch Based on the Rules of LMed S Algorithm

针对常用的平面拟合方法在有"噪声点"存在的情况下,会出现拟合不稳定的问题,本文采用稳健性较好的RANSAC算法,从机载Li DAR数据中提取出建筑物顶部面片。RANSAC算法进行参数拟合时,会存在一些缺陷,通过改进RANSAC算法(LMed S算法)可以达到更好的拟合效果。首先利用直通滤波器对点云数据进行简单的滤波,然后通过Voxel Grid滤波器对点云数据进行下采样。对下采样之后的点云数据,用LMed S算法提取建筑物顶部面片。试验表明,利用LMed S算法可以成功提取建筑物顶部面片,稳健性较好。

In view of the common plane fitting method can appear the problem of the unfitting under the condition of the existence of＂noise points＂,the RANSAC algorithm can extract the top patch of building from airborne LiDAR data with better robustness.When the RANSAC algorithm is fitted with parameters,there will be some defects,which can achieve better fitting effect by improving the RANSAC algorithm（ LMed S algorithm）.The point cloud data is filtered using the pass-through filter,and then the point cloud data is sampled by the Voxel Grid filter.For the sampled point cloud data,the top surface of the building is extracted using LMed S algorithm.The experiment results show that the LMed S algorithm can successfully extract the top patch of building. At the same time,it has a good robustness.