| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and an apparatus to generate compressed and indexed elevations of digital elevation models and to access them. SOLUTION: In one embodiment of the present invention, the method includes a step of compressing elevation data of a first portion of a digital elevation model (DEM) to generate first compressed elevation data, a step of storing the first compressed elevation data in a storage location pointed to by a first index, and a step of storing the first index. In another embodiment, the method includes a step of locating the first compressed portion of the digital elevation model (DEM) using the first index and a step of decompressing the first compressed portion to retrieve the first elevation data for at least one sample point in the digital elevation model. COPYRIGHT: (C)2010,JPO&INPIT |
