Improved algorithm for occlusion detection in large tilt aerial images based on elevation constraints

To improve the accuracy and efficiency of detecting occluded areas in large tilt images, this paper improves the Occlusion Detection Algorithm Based on Elevation Constraints on the basis of Angle Based Occlusion Detection Algorithm, and proposes an Occlusion Detection Algorithm Based on Elevation and Angle Constraints. This algorithm uses the spiral scanning method to judge the visibility of ground points layer by layer from the underground point, and fully utilizes the elevation, elevation angle with projection center, and visibility information of the inner layer point to judge the current point, greatly reducing the number of points that need to be judged. Compared with existing classical algorithms, it has the advantages of high accuracy and fast visibility analysis speed.