Journal Article

An Adaptive Surface Interpolation Filter Using Cloth Simulation and Relief Amplitude for Airborne Laser Scanning Data

Zhu, Haihong, Li, Feng, Li, Lin, Luo, Zhenwei, Shen, Hang

2021

Overview

Separating point clouds into ground and nonground points is an essential step in the processing of airborne laser scanning (ALS) data for various applications. Interpolation-based filtering algorithms have been commonly used for filtering ALS point cloud data. However, most conventional interpolation-based algorithms have exhibited a drawback in terms of retaining abrupt terrain characteristics, resulting in poor algorithmic precision in these regions. To overcome this drawback, this paper proposes an improved adaptive surface interpolation filter with a multilevel hierarchy by using a cloth simulation and relief amplitude. This method uses three hierarchy levels of provisional digital elevation model (DEM) raster surfaces with thin plate spline (TPS) interpolation to separate ground points from unclassified points based on adaptive residual thresholds. A cloth simulation algorithm is adopted to generate sufficient effective initial ground seeds for constructing topographic surfaces with high quality. Residual thresholds are adaptively constructed by the relief amplitude of the examined area to capture complex landscape characteristics during the classification process. Fifteen samples from the International Society for Photogrammetry and Remote Sensing (ISPRS) commission are used to assess the performance of the proposed algorithm. The experimental results indicate that the proposed method can produce satisfying results in both flat areas and steep areas. In a comparison with other approaches, this method demonstrates its superior performance in terms of filtering results with the lowest omission error rate; in particular, the proposed approach retains discontinuous terrain features with steep slopes and terraces.

• Publisher: MDPI AG
• Subject: Accuracy / adaptive residual thresholds / airborne laser scanning / Airborne lasers / Algorithms / Amplitudes / Cloth / cloth simulation / data collection / Digital Elevation Models / Filtration / ground filtering / Interpolation / landscapes / Laser applications / Lasers / Methods / Performance assessment / Photogrammetry / point clouds / relief amplitude / Remote sensing / Scanning / Seeds / Simulation / Terraces / Terrain / Thin plates / Thresholds / Topography