关键词: 激光扫描, 倾斜影像, 点云构建, 激光点云, 影像点云, 影像匹配

Abstract: Point clouds are an important part of 3D spatial data. Airborne laser scanning and tilt image matching are the two main point cloud construction techniques, which have commonalities and differences. The aim of this paper is to analyse the differences between airborne laser scanning and tilted image matching techniques for point cloud construction. Firstly, the specific methods of airborne laser scanning and tilted image matching point cloud construction are described, and then compare and analyse in terms of point cloud construction effect, data integrity, density, accuracy and vegetation penetration in conjunction with case studies. The results show that both techniques have good data integrity and can produce highly dense point clouds that far exceed the specification requirements, with comparable and high accuracy, but the laser scanning has loopholes in the occluded areas and distorted details in the blind local areas of image matching; the laser point cloud has good penetration and can achieve ground point cloud construction in different vegetation covered areas, while the image matching points have poor penetration. There is a lack in densely vegetated areas, can't even construct ground points. The results of the study provide a reference for the selection and optimization of subsequent point cloud construction methods, and have certain research and application value.

Key words: laser scanning, oblique image, point cloud construction, laser point cloud, imagery point cloud, imagery matching