Detection and Digital Representation of Ancient Architecture Damage Based on Laser Point Cloud: Case Study of the Zhengding Ancient City Wall

In view of the qualitative digitization and quantitative analysis of the damage status of ancient relics, this paper presents a method to automatically extract the surface damage area of the Zhengding ancient city wall. The point clouds of the damaged area were detected from the acquired laser point clouds using spatial change detection. The micro-deformation damage area is supplemented by extracting the local feature of the point cloud model. The experimental results show that the damaged region can be extracted effectively based on change detection and geometrical features, and the quantification and distribution of the damage status of cultural relics can be comprehensively expressed, which can provide important data for the renovation and restoration of relics.