传统点云断面提取是在3D产品基础上进行的，需要先对点云滤波获得地面点，再采样得到断面信息，这一过程处理数据量大、工作效率低而且断面成果质量难以保证，需要大量手工精化工作。该文针对公路断面专题制作的生产需求，提出了一种新的生产流程及方法，首先基于数字表面模型数据提取断面，对断面的点云集合进行二维投影，得到二维点阵列；再基于偏度平衡的滤波算法对点云阵列进行滤波；最后进行保留特征的断面点云抽稀。实验表明，新流程减少了数据处理量，有效提高了断面生产的效率和精度。
Traditional point cloud section extraction is carried out on the basis of 3D products. It is necessary to obtain ground points by filtering point cloud firstly and then sampling to obtain sections. The process suffers low work efficiency and unguaranteed quality of the section production, requiring a lot of manual refinement work. This paper proposes a new production process and method for the production demand of highway cross section thematic production. Firstly, a cross section is extracted based on digital surface model (DSM), and the point cloud set of the cross section is two-dimensionally projected to obtain a two-dimensional point array. Then, the point cloud array is filtered based on the skewness-balanced filtering algorithm, and finally a feature preserving cross section point cloud is extracted. Practice has proved that the new process reduces the amount of data processing and effectively improves the efficiency and precision of cross section production.
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