Research on topographic change extraction and contour line updating technology based on DEM in different times
In order to effectively improve the currency of topographic deta,and meet the needs of rapid detection of topographic changes and geomorphological data updating in digital line graph(DLG)updating,this paper proposes a technical method for topographic change extraction and contour updating based on the digital elevation model(DEM)in defferent times.By calculating and analyzing the differ-ence between the old and new DEMs,the method selects appropriate threshold values of elevation change and area change,combines the latest digital orthophoto map(DOM)to identify and extract the effective region of terrain change,and combines contour inversion and elevation interpolation assignment to realize the updating of geomorphic data in the changing region.This technique has been applied in the pilot project of 1:10 000 terrain element data refinement updating in Anhui Province,which realizes the efficient and accurate updating of the data,and has good reference and application value in the terrain change region discovery and contour updating project.
NETL
NSTL
万方数据
维普
