Firstly we merge the edge detected image and the same-size voronoi-diagrams,then adopt the recent Antipole strategy technique about data structure aimed to optimize proximity queries to speed up the search process,and finally search one tile image with the similar shape in the data base to mosaic the voronoi region.

In order to avoid the tedious work in the traditional method generating Digital Elevation Model(DEM) based on the contour map,which picks out vast discrete points and then establishes large Triangulated Irregular Networks(TIN),the polygon region method was proposed.

Based on the incremental idea and the uniform grid, constrained Delaunay triangles can be computed in local ranges for arbitrary planar polygonal domains.