车载激光点云数据的栅格化处理

Transforming vehicle-borne laser point cloud to grid point cloud

车载激光点云由于车辆的震动和点云的融合,得到的数据为散乱空间点云。本文通过对空间点云进行两个方向的排序,得到以x值为主排序,z值为次排序的点云图,然后设置栅格,对于每个栅格点,找到投影在XOZ投影面内与其距离最近的激光点,将该激光点的y值赋给栅格点,得到与该区域空间点云相对应的栅格化点云。在按照X值排序时,根据点云的特点给出了一种插入排序算法。实验结果表明栅格化后的点云与原点云在表现建筑结构上效果一致。散乱点云栅格化后为点云的进一步分析打下基础。

Point cloud got by vehicle-borne laser is scattered because of the vehicle＇s vibration and the fusion of point clouds obtained in different time. The points of the cloud are sorted by x value firstly. Then the points, which are in the same column, are sorted by their z value. A grid is given in XOZ plan （the projective plan） , and the grid point＇s y value is the laser point＇s y value which is nearest to the grid point in XOZ plan. When the points are sorted by their x value, an algorithm is given on the base of point cloud＇s characteristic. The experiment result shows that the grid point cloud has the same effect with the scattered point cloud. The grid point cloud can be used to analyze the scattered point cloud.