Abstract This paper studies the fidelity level of the extracted LiDAR (Light Detection And Ranging) building point cloud in relation to the original building. In this context, the building point cloud is compared with a reference model. This comparison allows a deep understanding of the point cloud structure with respect to both the actual building and the constructed model. Consequently, the source of the incompatibility in a (reference or constructed) building model is determined and described. Thus, this study considers four aspects of the building point cloud. First, the errors of building point cloud extraction and the undesirable points are quantified. Hence, it is found that the percentages of undesirable points are sometimes considerable (between 15% and 70%). Second, the evaluation of the fit of the altimetry with the reference model shows that the roof plane equations calculated from LiDAR data can be more precise than those of reference model, Third, the segmentability level between different point densities and building typologies are variable. Finally, the per plane comparison mentions the incompatibility of the plane boundaries of point cloud with reference model. Moreover, considerable differences are noted between the theoretical and the true point densities.

中文翻译：

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LiDAR构建点云与云结构深度理解参考模型对比

摘要 本文研究了提取的 LiDAR（光检测和测距）建筑点云相对于原始建筑的保真度水平。在这种情况下，将建筑点云与参考模型进行比较。这种比较可以深入了解实际建筑和构建模型的点云结构。因此，确定并描述了（参考或构建的）建筑模型中不兼容的来源。因此，本研究考虑了构建点云的四个方面。首先，对构建点云提取的误差和不需要的点进行量化。因此，发现不良点的百分比有时相当大（在 15% 和 70% 之间）。第二，高度计与参考模型的拟合评估表明，根据激光雷达数据计算出的屋顶平面方程可以比参考模型更精确。第三，不同点密度和建筑类型之间的可分割性水平是可变的。最后，每平面比较提到了点云的平面边界与参考模型的不兼容。此外，注意到理论点密度和真实点密度之间存在相当大的差异。