METHOD, SYSTEM AND PROGRAM FOR PREPARING HIGHLY PRECISE CITY MODEL USING LASER SCANNER DATA AND AERIAL PHOTOGRAPHIC IMAGE

PROBLEM TO BE SOLVED: To construct a highly precise three-dimensional city model by combining the advantages of the altitude precision of laser scanner data, the advantages of the high resolution of an aerial photograph, and a conventional variable density DEM (Digital Elevation Model). SOLUTION: This system is provided with a coordinate calculating module 10, a ground height calculating module 11, a region division processing part 15, a horizontal face stereo matching processing part 16, a region division processing part 17, a polygon generation processing part 18, and a three-dimensional modeling processing part 19. Each of stereo aerial photographic pictures is divided into regions to obtain an image region whose hue is uniform. Stereo matching is carried out by using the altitude value of the three-dimensional point group of the laser scanner overlapping each color region as an initial value. When the calculation result of the obtained altitude value represents almost the same altitude as the initial value, the altitude value being the calculation result is applied to the region to generate the DSM. Then, the horizontal region of the obtained DSM is recognized by region division, and linear extraction is carried out in a peripheral region on the stereo image corresponding to each region, and the results are polygonzied. COPYRIGHT: (C)2004,JPO