Research on 3D geometric modeling of urban buildings based on airborne lidar point cloud and image

Abstract

Buildings are the most important elements in cities. Building urban building models is of great significance for the establishment of digital cities. The level of its modeling technology restricts the development of urban 3D modeling technology. In order to improve the accuracy of 3D geometric modeling of urban buildings and truly reflect the spatial layout of urban buildings, the 3D geometric modeling of urban buildings based on airborne LiDAR point cloud and image is studied. The airborne LiDAR and tilt photogrammetry technology are analyzed, and the airborne LiDAR point cloud data is filtered by using the two-level grid to eliminate the gross error, and the airborne LiDAR point cloud data is filtered by using the morphological filtering algorithm. Through the principle of spatial location, the spatial geographic location information of the oblique image is restored. Extract the step line feature of the urban building point cloud and the roof patch of the urban building, accurately register and locate the urban building model based on the inclined image, and combine the urban building texture map to realize the three-dimensional geometric modeling of the urban building. The experimental results show that the proposed method has good 3D geometric modeling effect of urban buildings, can truly reflect the spatial layout of urban buildings, and effectively improve the accuracy and efficiency of 3D geometric modeling of urban buildings.