针对广西地形激光LiDAR点云滤波处理的研究及应用

Research and application of Guangxi laser LiDAR point cloud filter processing

机载LiDAR能够快速获取精确的高分辨率数字地面模型以及地面物体的三维坐标,是一种DEM数据快速生产的重要手段,在地球空间信息科学等领域具有广阔的发展前景和应用需求。然而在中国广西地区,由于地形地貌存在大量陡峭石山,地形破碎,以及部分地区植被十分茂密等特点,导致LiDAR数据的常规滤波算法将丢失大量地面点,增加人工编辑工作量,最终造成DEM生产质量不高。本文所提出的三个LiDAR点云数据精细化处理改进算法能够较好地识别这些特殊地形,采取一定的调整算法和处理,对陡石山进行重分类;对水体、断壁边界添加断裂线;对茂密植被区重新模拟地面,基本能大致修复丢失的地表,具有较强的实用性,也较大程度地提高了作业效率,尤其适合广西植被覆盖高、地形破碎、山地占比高的地区。

The airborne LiDAR can quickly acquire accurate high-resolution digital ground model and three-dimensional coordinates of ground objects.It is an important means for rapid production of DEM data,and has broad development prospects and application requirements in the field of geospatial information science.However,in Guangxi,China,due to the existence of a large number of steep rocky mountains,broken terrain,and dense vegetation in some areas,the conventional filtering algorithm of LiDAR data will lose a lot of ground points,increase the labor of manual editing,and ultimately lead to the quality of DEM production. The improved algorithm of LiDAR point cloud data improved by the three algorithms proposed in this paper can identify these special terrain well,adopt certain adjustment algorithms and processing,reclassify the steep rock mountain,and add the fault line to the water body and the fault wall boundary;The dense vegetation area re-simulates the ground,which can basically repair the lost surface.It has strong practicability and greatly improves the operation efficiency.It is especially suitable for areas with high vegetation coverage,broken terrain and high mountain share in Guangxi.