RESEARCH ON URBAN CONSTRUCTION LAND CHANGE DETECTION METHOD BASED ON DENSE DSM AND TDOM OF AERIAL IMAGES
The scale of urban construction land is an important factor of the process of urbanization. This paper presented an urban construction land change detection method combining dense DSM difference and TDOM tree extraction of traditional aerial photos: the pixel-level DSM and TDOM for two period are obtained by Semi-Global Matching (SGM) and Multi View Stereo (MVS), respectively. After DSM pre-processing including noise filter and hole filling, the difference of DSM is calculated. The segmentation and tree extraction of TDOM are proposed to reduce the change errors caused by the crown influence of different seasons. Based on this method, 2 experiments were carried out. One was for the urban construction land located at 5th ring road south in Beijing with ADS80 aerial images obtained in 2016 and 2017, and the other was for the building demolition and construction of Dongcheng and Xicheng District of Beijing with UltraCam, the frame camera and RCD30 between 2015 and 2017. Through the experiments, it was concluded that the result of the method could identify all the changes both in the plane and in the elevation, and the edges of the change patches were clear and regular, which could assist checking the manual change extraction results. The minimum area of the change patches could be 5 m 2 with the DSM resolution of 0.2 m, which was of great significance for the urban construction change detection including the factory, residential area and also the urban regional greening.