Andreas Behm


Using the techniques of this disclosure, a system can efficiently and accurately select digital maps from a large number candidate available maps related to a specified geographic area. As discussed in more detail below, for each map, the system identifies a set of tiles (equalsized units into which maps are divided) fully covering the map and obtains a quality metric for the map. The tiles are organized into a hierarchical data structure such as a quadtree, where each layer corresponds to a certain level of magnification. The system then generates inverted indices for the set of tiles, such that a tile is a key and the {map, quality metric} is the corresponding value. The system updates the nodes of the data structure using the indices, so that the maps subsequently can be quickly retrieved accurately and efficiently.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.