Operating and managing single three-dimensional building model individually are critical in the application of oblique photography models. However, these models are usually complete and continuous, and the single three-dimensional building model in these models cannot be managed individually. Generally, achieving a single three-dimensional building model requires a human-computer interaction to determine the cutting range, but this process is time-consuming and inefficient. To overcome this problem, this study proposed a new method for automatically achieving single three-dimensional building model without the need for human-computer interaction. First, the point clouds of an oblique photography model are divided into virtual grids, and the point clouds in each virtual grid are seen as a whole. In this way, the number of point clouds involved in the calculation is reduced, thereby improving computing efficiency. Second, the point clouds of a building facade are extracted by setting the height difference. By comparing the height difference between the highest point and the lowest point of the grid with height difference threshold, all point clouds in the grid that do not meet the requirements are eliminated. Third, the point clouds of the building facade are classified, and the contour line is extracted by the classified point clouds. Finally, the single three-dimensional building model is achieved by reconstructing the triangles that intersect with the extracted contour line. Experimental results show that the proposed method can effectively achieve single bodies automatically from an oblique photography building model. This method is then useful for achieving single three-dimensional building model from massive oblique photography data.

中文翻译：

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一种基于倾斜摄影数据自动生成单一三维建筑模型的新方法

单独操作和管理单个三维建筑模型在倾斜摄影模型的应用中至关重要。但是，这些模型通常是完整的、连续的，这些模型中单一的三维建筑模型无法单独管理。一般来说，实现单一的三维建筑模型需要人机交互来确定切割范围，但这个过程耗时且效率低下。针对这一问题，本研究提出了一种无需人机交互即可自动实现单个三维建筑模型的新方法。首先，将倾斜摄影模型的点云划分为虚拟网格，将每个虚拟网格中的点云看成一个整体。通过这种方式，减少了参与计算的点云数量，从而提高了计算效率。其次，通过设置高差来提取建筑立面的点云。通过将网格最高点与最低点的高度差与高度差阈值进行比较，剔除网格中所有不符合要求的点云。第三，对建筑立面的点云进行分类，通过分类后的点云提取等高线。最后，通过重构与提取的轮廓线相交的三角形来实现单一的三维建筑模型。实验结果表明，所提出的方法可以有效地从倾斜摄影建筑模型中自动实现单体。