Comparison of Two Approaches on Terrain Change Detection and Updating

The paper makes comparison between "terrain change detection and updating based on VLL matching" and "terrain change detection and updating based on orthoimage matching" in theory at first. The two approaches both can detect changed area and update terrain data simultaneously with up-to-date aerial stereo pair and outdated DEM. Two study areas in Shanxi Province China are employed to test and compare two detection approaches in experiment. Changed areas detected by each mean are marked on imagery. Overlay of orthoimages and contour generated with updated DEM from standard data and two presented approaches are illustrated and compared. And statistics of the updated terrain data produced by the two approaches are also analyzed to investigate the differences. Updated terrain data is mostly in consistent with products made by experienced operators. And it shows that the two approaches can be used for terrain change detection and updating in practice.