测绘学报 ›› 2021, Vol. 50 ›› Issue (5): 621-633.doi: 10.11947/j.AGCS.2021.20200270

• 摄影测量学与遥感 • 上一篇    下一篇

结合区域增长与RANSAC的机载LiDAR点云屋顶面分割

赵传1,2, 郭海涛2, 卢俊2, 余东行2, 林雨准2, 姜怀刚3   

  1. 1. 火箭军指挥学院, 湖北 武汉 430012;
    2. 信息工程大学地理空间信息学院, 河南 郑州 450001;
    3. 海图信息中心, 天津 300450
  • 收稿日期:2020-06-23 修回日期:2021-02-02 发布日期:2021-06-03
  • 通讯作者: 郭海涛 E-mail:ghtgjp2002@163.com
  • 作者简介:赵传(1991-),男,博士,研究方向为点云数据处理、基于机载LiDAR点云数据的建筑物三维模型重建。E-mail:zc_mail163@163.com
  • 基金资助:
    国家自然科学基金(41601507)

Roof segmentation from airborne LiDAR by combining region growing with random sample consensus

ZHAO Chuan1,2, GUO Haitao2, LU Jun2, YU Donghang2, LIN Yuzhun2, JIANG Huaigang3   

  1. 1. Rocket Force Command College, Wuhan 430012, China;
    2. Institute of Geospatial Information, Information Engineering University, Zhengzhou 450001, China;
    3. Chart Information Centre, Tianjin 300450, China
  • Received:2020-06-23 Revised:2021-02-02 Published:2021-06-03
  • Supported by:
    The National Natural Science Foundation of China (No. 41601507)

摘要: 建筑物屋顶面大小差异较大、形状复杂、数量不确定等特点,以及机载LiDAR点云密度不均、分布不规则、缺乏语义信息等特性,对屋顶面的准确分割造成了很大干扰,因此现有分割方法的精度和适用性仍有待提高。针对上述问题,本文提出一种结合区域增长与RANSAC的机载LiDAR点云屋顶面分割方法。首先,引入稳健的法向量估计算法计算点云法向量,利用提出的迭代区域增长策略和RANSAC提取多个可靠屋顶面片;然后,基于可靠屋顶面片参数和RANSAC计算内点的思想,迭代合并可靠屋顶面片,并精化屋顶面参数;最后,计算未能通过前面步骤分割的点到各屋顶面的垂直距离,将其标记为距离最小且小于阈值的屋顶面,并通过局部范围内投票的方式精化屋顶面分割结果。利用多个具有代表性的建筑物点云和一组区域建筑物点云进行试验,结果表明,所提出的方法可有效地分割不同复杂程度的建筑物屋顶面,并能较好地分割面积较小的屋顶面,以屋顶面和单点为评价单元的平均分割正确率为95.56%和97.93%,分割的结果可为建筑物三维模型重建、点云精简等应用提供可靠的信息。

关键词: 屋顶面分割, 迭代区域增长, RANSAC, 机载LiDAR点云

Abstract: Roofs of a building have the characteristics of greatly different size, complex shape and uncertain number, and airborne LiDAR point cloud has the characteristics of uneven density, irregular distribution and without any semantic information, which make many existing airborne LiDAR roof segmentation methods ineffective and their applicability and precision still need to be improved. Thus, an airborne LiDAR roof segmentation method combining region growing with random sample consensus is proposed in the paper. Firstly, the robust normal estimation is introduced to calculate point cloud normal, a proposed iterative region growing strategy and random sample consensus are applied to extract many reliable roof patches. Then, an iterative process is performed to merge these roof patches based on their parameters and the idea of inlier selection of random sample consensus(RANSAC), and roof parameters are refined by the process. Finally, the orthogonal distance of points which are not segmented by the previous steps to each roof is calculated, and points are assigned to the corresponding roof with the minimum orthogonal distance and less than the threshold, and the roof segmentation results are refined by voting in the local neighborhood. Multiple representative building point clouds and a group of regional building point clouds are used in the experiment. The results show that the proposed method can effectively segment roofs of buildings with different complexity, and can also effectively segment roofs with small area, the average segmentation correctness is 95.56% and 97.93% by using a roof and a single point as the basic evaluation unit. The results can provide reliable information for applications such as three-dimensional building model reconstruction and point cloud reduction.

Key words: roof segmentation, iterative region growing, RANSAC, airborne LiDAR point cloud

中图分类号: