| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for generating a compressed navigation map database. <P>SOLUTION: Uncompressed navigation map data contains various building blocks of navigation data, and each building block addresses a specific functional aspect of navigation data, also each block contains strings of data. A method for generating a compressed navigation map database comprises steps of: determining, for each block of the uncompressed navigation map data, the most frequent substring of the block; storing, for each block, the determined most frequent substring of the block in a seed block; replacing, for each block, the determined most frequent substring in the strings stored in the seed block by a reference to the seed block, to generate a compressed block for each block; and storing, for each block, the compressed block and the seed block in order to generate the compressed navigation map database. <P>COPYRIGHT: (C)2013,JPO&INPIT |
