Urban building change detection method based on LiDAR point cloud spatial difference analysis

The invention discloses an urban building change detection method based on LiDAR point cloud spatial difference analysis. The method comprises the steps that 1, LiDAR point cloud data with different time phases are respectively preprocessed, and DSM and DTM of the different time phases are obtained through a linear interpolation algorithm; 2, two periods of the DSM obtained in the step 1 are subtracted to obtain an elevation difference model; 3, spatial difference analysis is carried out on the elevation difference model, and a candidate change area is extracted; 4, spatial features of a LiDAR point cloud are used for extracting direct features and elevation grain features; 5, building and vegetation classification is achieved; 6, superposition and overlay analysis is carried out on the candidate change area, and the building change attribute is determined. The advantages of the LiDAR data on three-dimensional representation of the building complex structure and the topological relation are fully achieved, and building three-dimensional change detection is carried out.