Heritage documentation is implemented by digitally recording historical artifacts for the conservation and protection of these cultural heritage objects. As efficient spatial data acquisition tools, laser scanners have been widely used to collect highly accurate three-dimensional (3D) point clouds without damaging the original structure and the environment. To ensure the integrity and quality of the collected data, field inspection (i.e., on-spot checking the data quality) should be carried out to determine the need for additional measurements (i.e., extra laser scanning for areas with quality issues such as data missing and quality degradation). To facilitate inspection of all collected point clouds, especially checking the quality issues in overlaps between adjacent scans, all scans should be registered together. Thus, a point cloud registration method that is able to register scans fast and robustly is required. To fulfill the aim, this study proposes an efficient probabilistic registration for free-form cultural heritage objects by integrating the proposed principal direction descriptor and curve constraints. We developed a novel shape descriptor based on a local frame of principal directions. Within the frame, its density and distance feature images were generated to describe the shape of the local surface. We then embedded the descriptor into a probabilistic framework to reject ambiguous matches. Spatial curves were integrated as constraints to delimit the solution space. Finally, a multi-view registration was used to refine the position and orientation of each scan for the field inspection. Comprehensive experiments show that the proposed method was able to perform well in terms of rotation error, translation error, robustness, and runtime and outperformed some commonly used approaches.

中文翻译：

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基于形状描述符的有效概率配准用于遗产现场检查

通过数字记录历史文物来保护和保护这些文化遗产，从而实现遗产文献的记录。作为有效的空间数据采集工具，激光扫描仪已广泛用于收集高度精确的三维（3D）点云，而不会损坏原始结构和环境。为了确保所收集数据的完整性和质量，应该进行现场检查（即，现场检查数据质量）以确定是否需要进行其他测量（即，对质量有问题（例如数据丢失）的区域进行额外的激光扫描）和质量下降）。为了便于检查所有收集的点云，尤其是检查相邻扫描之间重叠的质量问题，应将所有扫描一起注册。从而，需要一种能够快速而强大地注册扫描的点云注册方法。为了实现这一目标，本研究通过整合拟议的主要方向描述符和曲线约束，为自由形式的文化遗产提出了一种有效的概率配准方法。我们基于主要方向的局部框架开发了一种新颖的形状描述符。在框架内，生成其密度和距离特征图像以描述局部表面的形状。然后，我们将描述符嵌入概率框架中以拒绝模棱两可的匹配。空间曲线被集成为限制解空间的约束。最后，使用多视图配准来完善每次扫描的位置和方向，以进行现场检查。