Method and apparatus for representing an area of a raster image by a centerline

摘要

One embodiment of the present invention provides a system that can represent an area of a raster image by a centerline. During operation, the system receives a planar map which represents a raster image that contains a region. Note that the region corresponds to a face in the planar map whose edges correspond to the boundaries of the region. Next, the system determines a centerline for a subregion within the region which is currently represented by an outline. The system then transforms the planar map so that the subregion is represented by the centerline.