高级检索

植被茂密地区点云双重滤波方法研究

Double-filtering method for point cloud data in densely vegetated area

  • 摘要: 为了解决目前机载激光雷达点云滤波算法中特征单一、运算效率低、植被覆盖区效果较差等问题,提出一种植被茂密地区的点云自适应双重滤波方法。首先利用回波分离方法,分别提取点云的单次回波和末次回波进行粗滤波处理;然后利用偏度平衡理论进行单次回波的强度阈值确定,同时利用最大类间方差法对首次回波和末次回波的高程差进行高差运算,实现末次回波高差阈值自动化,并融合粗滤波后单次回波和末次回波的点云数据;最后,利用不规则三角网渐进加密滤波算法对融合后的点云数据进行精滤波处理,并通过了实验验证。结果表明,3组数据集的Ⅱ类误差都相对较低,分别为1.06%, 1.64%, 1.34%。结合回波信息和高差信息的双重滤波方法不仅能较好地剔除植被,而且能较好地保留地形细节。

     

    Abstract: In order to solve the problems such as single feature, low calculation efficiency, and poor effect of vegetation coverage of the current airborne light detection and ranging(LiDAR) point cloud filtering algorithm, an adaptive double filtering method for point cloud in densely-vegetated areas was proposed. Firstly, the single and last echo of point cloud were extracted respectively and processed by coarse filtering by using the echo separation method. Then, the skewness balance theory was used to determine the intensity threshold of the single echo, and the maximum inter-class variance method was used to calculate the height difference between the first echo and the last echo, so as to realize the automation of the height difference threshold of the last echo. And the point cloud data of the single echo and the last echo after rough filtering were integrated. Finally, the incremental encryption filtering algorithm of triangulated irregular network was used to carry out the fine filtering processing on the fused point cloud data, and the experimental verification had been done. The results show that the type Ⅱ errors of the three data sets are relatively low of 1.06%, 1.64%, and 1.34% respectively. The dual filtering method that combines echo information and height difference information can not only eliminate vegetation, but also retain terrain details.

     

/

返回文章
返回