Abstract

The method of the present invention which employs conflation is based on pairing chains of arcs in order to determine the matching intersections between them. The chains are formed a priori in each map by using both attributes and geometric properties of the arcs. The intersections of chains are treated as relations, stored in a simple external custom relational database. The matching procedure is a set of the standard operations on RDBMS, as well as the sieving out of all possible ambiguous identifications. As a result, both maps become partitioned by the chains into much smaller pairwise matched areas called wards. The positional and semantic information from the matched chains is mapped onto the merged map. The mapping is performed by a general nonlinear transformation function. The transformation is then extended to the mapping of the unmatched content of wards onto the ultimate map. Any combination of geometry and attribute can be selected from either of a pair of matched wards for inclusion in the merged ward.

Other References

• Alan John Saalfeld, Conflation: Automated Map Compilation; Ph.D. Dissertation, University of Maryland, (College Park, Maryland, 1993), pp. 1-133
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• Conflation Of Digital Maps; Z. Deretsky, U. Rodny, M. White, IVHS America 3rd Annual Meeting, Washington, D.C., Apr. 14-17, 1993
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• Piecewise Linear Rubber-Sheet Map Transformation, Marvin S. White, Jr. and Patricia Griffin, The American Cartographer, vol. 12, No. 2, 1985, pp. 123-131
• Conflation--Automated map compilation; Alan Saalfeld, Int. J. Geographical Information Systems, 1988, vol. 2, No. 3, pp. 217-22