距离加权与冠层控制的LiDAR CHM凹坑去除方法A pits removal method for LiDAR CHM based on distance weighting and canopy control
刘一成,王成,习晓环,王金亮,张海清
摘要(Abstract)：
针对机载激光雷达(LiDAR)获取的高密度点云数据为森林冠层高度模型(CHM)构建提供了可能,但在应用中通常会出现局部无效值(凹坑)现象,影响森林高度等参数的提取精度的问题,该文提出基于距离加权和冠层控制的CHM凹坑去除方法。首先加权计算每个像素相似阈值判断可能凹坑,然后利用形态学运算控制冠层范围并确定最终凹坑,继而填入对应的CHM中值滤波后的值来去除CHM凹坑。通过与高斯滤波、均值滤波、中值滤波等方法比较,该文方法在凹坑的去除效果以及保留冠层形态方面均有优势,且对不同分辨率CHM具有普适性,直接提取单木数量精度可达96.7%,相比原始CHM以及另外4种方法处理的CHM所提取单木数量,精度分别提高2.38%、13.92%、17.81%、6.54%、2.38%;直接提取平均树高精度为99.41%,相比原始CHM及另外4种方法CHM精度分别提高0.16%、0.8%、0.56%、0.75%、0.16%。
关键词(KeyWords)： 激光雷达;冠层高度模型;凹坑;距离加权;冠层控制
基金项目(Foundation): 国家自然科学基金面上项目(41871264);; 云南师范大学研究生科研创新基金项目(ysdyjs2019140)
作者(Author): 刘一成,王成,习晓环,王金亮,张海清
DOI: 10.16251/j.cnki.1009-2307.2021.04.016
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