Filtering LiDAR data based on adjacent triangle of triangulated irregular network

The filtering of LiDAR points cloud data is a fundamental procedure in the production of Digital Elevation Model. Against the lack of using the relationship between the adjacent terrain and the points to be judged in the point cloud filtering, a LiDAR points cloud data filtering algorithm based on adjacent triangles in TIN (Triangulated Irregular Network) is proposed. It utilizes the elevation information of each triangle's adjacent triangles to detect the building edge points, and acquires the building points by region growing, then detects the isolated points with the morphological filtering algorithm, finally determines the ground point set and generates DEM. We evaluate the performance of the proposed method on the ISPRS LiDAR reference dataset. Experimental results show that the algorithm can effectively remove non-ground points, keep the ground points and minimize total error rates effectively while maintaining acceptable Type I and Type II error rates.