多站地面三维激光扫描强度数据纠正与归一化

Correction and Normalization of Multi-Scan Terrestrial Three-Dimensional Laser Scanning Intensity

针对地面三维激光扫描强度纠正局限于单站点云强度纠正的问题,提出基于高斯混合模型的直方图匹配方法,对多站点云强度进行纠正。该方法通过拟合距离-强度模型与入射角-强度模型,对单站点云强度值进行纠正。利用高斯混合模型拟合纠正后的单站点云强度直方图,并对直方图进行分割。通过子直方图匹配对多站点云强度进行归一化。实验结果表明,本文提出的方法不仅可以有效纠正单站点云强度值的差异,也可以改善多站点云强度值的差异。

Current point cloud intensity correction is confined to single scan station. In order to solve this problem, we propose a histogram equalization method for multi-scan intensity based on Gaussian mixture model. Firstly, the range-intensity and incidence angle-intensity correction models are used to correct the intensity for a single scan station. Then Gaussian mixture model is used to fit the histogram of intensity distribution after correction and segment the histogram. Finally, normalization of multi-scan intensity is achieved through sub-histogram matching. The experiment results indicate that the proposed method can not only correct the intensity of a single scan station efficiently, but also improve the inconsistence among diifferent scan stations.