A New Approach for Mountain Areas Cartography

From now on, the French National Mapping Agengy (IGN France) is set up with the BD TOPO®. This is a topographic vector database that covers the whole national territory. IGN has decided to product base maps at 1:25k and 1:50k from this database. On topographic mountain maps, rocks areas are among the most difficult map elements to represent, dealing with digital cartography. In the past, they were drawn manually by experienced cartographers, using graphic means and working with aerial photographs. Nowadays, we need to focus on two points with a digital approach. The first one is the detection and an automated classification of concerned areas. The next one is the development of an adapted cartographic representation of rocks and screes areas. This article presents the first results on these problems. As far as possible, we aim at having automated high mountain cartography with lower production costs. Also, we would like it to be as expressive as it was in previous maps. This is to keep the same cartographic quality of the current base map at 1:25k and 1:50k.