Geographic map understanding, attributes computation for hydrographic network

We present three algorithms integrated in a geographic map understanding project. They directly work on the blue plane, which contains only hydrographic data. The first one reconstructs the fragmented areas, which symbolize the rivers, with a vector representation of the objects´ boundaries. The second and the third algorithms concern the hydrographic network graph attribution, respectively the dashed/solid line, and the bordered by trees attribution. Those two methods use drawing rules and high-level knowledge defined on the hydrographic network graph