The French Institut Géographique National (IGN) wants to develop an automated map understanding system, for the geographicaludmaps at scale 1/25000. The aim is to automatically convert the 2000 cartographic paper-maps in a geographical objectsuddatabase, directly usable by a GIS. This paper describes a high-level method for the automated reconstruction of the networkudgraphs, represented on the French geographic maps . This method is applied to the hydrographic and road networks, symbolizedudwith dashed lines, interrupted solid lines and fragmented textured areas . The graph theory paradigm is used, which allows toudnaturally model those networks by graphs, and to formalize the constraints for their reconstruction . A priori knowledges on naturaludand cartographic networks are directly used in the reconstruction process, and translated either as invariants the networks mustudverify during the reconstruction, either as quality criterion for the likely considered connexions .
展开▼
