Point Cloud Denoising Processing Technology for Complex Terrain Debris Flow Gully

Ground 3D laser point cloud denoising processing is the key to realize terrain 3D modeling of debris flow ditch. Most point cloud denoising methods have poor effect on the complex terrain, do not ideally preserve the terrain features either. This study put forward a point cloud denoising processing method based on terrain feature refinement. Firstly, based on the relief amplitude and slope information reflected by the original point cloud, the terrain niche index model was established, and the natural discontinuity method was used to block the point cloud in the experimental area. Secondly, a multi-scale virtual grid was constructed based on the terrain and vegetation growth of each block to extract more accurate initial ground points, and the initial terrain surface was constructed based on these points. Finally, a set of ground point judgment parameters is determined, and the ground point is extracted in combination with the initial terrain surface, to realize the denoising processing of the debris flow valley point cloud. The results quality is assessed with the traditional triangulated irregular network denoising processing method. The analysis results show that the denoising method based on terrain feature refinement not only improve the quality of point cloud denoising and effectively remove the vegetation with different height characteristics under different slope environments in the debris flow valley, but also keep the terrain structure features very well.