A STRUCTURE-BASED APPROACH FOR MATCHING ROAD JUNCTIONS WITH DIFFERENT COORDINATE SYSTEMS

Abstract. Effective matching algorithm of multi-source road networks is of vital importance for integration, updating and maintenance. In traditional matching methods, buffering and geometrical distances are basic strategies for potential matches searching, and the coordinate systems need to be similar. These methods may be invalid if the coordinate systems are unknown. Therefore, a novel approach of comparing the structures of urban road networks based on skeleton extraction is proposed in this paper. Firstly, the similarity measurement between junctions is described by a cluster comparison consisted with its neighbour junctions. And then the hierarchical strokes are recognized as a global structure to match, which eliminates the effect of the different coordinate systems. Finally, graphs converted from hierarchical skeletons of road network in different coordinate systems are compared and the most probable junction correspondences are established with maximum common subgraph algorithm. Based on the corresponding junctions, an affine transformation is able to be established between two unknown coordinate systems, and the remaining junctions matching will be conducted by traditional geometric methods. An experiment of matching road networks is carried out without any other geographic positional information. The result shows that no matter how significant the difference of coordinate systems are, it is still able to find the correct matches, which is impossible by traditional methods.