Compilation of mosaics from separately scanned line drawings

In automatic line drawing interpretation (e.g. map interpretation), one of the problems encountered is the finite size of scanners, or that scanners of the required size are not available. Often, one large scan is necessary for the interpretation process, instead of several smaller ones generated by the usual scanning in parts. This paper describes a method for automatically compiling mosaics from separately scanned line drawings. A mosaic is a collection of separately obtained images which are combined to form one larger image. The method is based on vectorization of the line drawings, which is used to select the control points for a geometric transformation automatically. It is not necessary to specify the overlap area between the line drawings. The resulting system is evaluated using large scale maps. Experiments with different overlaps between the line drawings were done. Results are good: the algorithm succeeds in finding accurate parameters for the transformation