Acta Geodaetica et Cartographica Sinica ›› 2021, Vol. 50 ›› Issue (5): 621-633.doi: 10.11947/j.AGCS.2021.20200270

• Photogrammetry and Remote Sensing • Previous Articles     Next Articles

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)

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

CLC Number: