Journal of Geo-information Science ›› 2019, Vol. 21 ›› Issue (4): 608-614.doi: 10.12082/dqxxkx.2019.180425

• Orginal Article • Previous Articles     Next Articles

Accuracy Assessment of Airborne LiDAR Point Cloud Using High Precision DLG as Reference

Pengjie TAO(), Mengxiao SONG, Yansong DUAN*()   

  1. School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China
  • Received:2018-09-01 Revised:2019-01-11 Online:2019-04-24 Published:2019-04-24
  • Contact: Yansong DUAN E-mail:pjtao@whu.edu.cn;ysduan@whu.edu.cn
  • Supported by:
    National Key Research and Development Program of China, No.2017YFB0503004;National Natural Science Foundation of China, No.41801390;Open Topic of the Hunan Key Laboratory of Land Resources Evaluation and Utilization, No.SYS-MT-201802

Abstract:

LiDAR is an active topographic mapping technique for obtaining high precision surface geometric information. In recent years, LiDAR point cloud has been widely used and gradually become a new standard geospatial information product, because of its efficiency, directness and easy availability. Due to its high accuracy, LiDAR point cloud data can be used as georeference data for aerial triangulation of unmanned aerial vehicle (UAV) imagery with sparse ground control points (GCPs) or even without GCP. Because the accuracy of aerial triangulation strongly depends on the accuracy of georeference data itself, so it is of great practical significance to evaluate the accuracy of LiDAR point cloud as georeference data. In this study, we proposed a method for evaluating the accuracy of airborne LiDAR point cloud data using high precision digital line graphic (DLG) as reference data. This method realizes not only the assessment of the vertical accuracy of LiDAR point cloud, but also the reliable assessment of the horizontal accuracy of LiDAR point cloud. Firstly, the vertical accuracy was evaluated by comparing the elevations of the elevation points in DLG with the elevations of the LiDAR points at corresponding positions. Secondly, the facade points of LiDAR buildings were extracted and projected into a horizontal plane, and their distances from the outlines of buildings in DLG were calculated to evaluate the horizontal accuracy of LiDAR point cloud. Due to the existence of a large number of elevation points and building contours in the DLG, the accuracy assessment samples were abundant, and the assessment results could reflect the true accuracy level of LiDAR point cloud. The experiments showed that the horizontal and vertical accuracy of LiDAR point cloud in the test area could reach 7.2 cm and 8.3 cm, respectively, which proved that LiDAR can be used as an effective control data for large scale UAV aerial remote sensing purpose.

Key words: Airborne LiDAR point cloud, high precision DLG, facade points extraction, horizontal accuracy, vertical accuracy