IMAGE DISPLAY DEVICE, IMAGE DISPLAY METHOD, IMAGE DISPLAY PROGRAM AND COMPUTER READABLE RECORDING MEDIUM

摘要

An image display device synthesizes and displays map information stored by being separated into a plurality of layers for a same area. A setting section (101) sets whether each of the pieces of map information in the plurality of layers is to be automatically updated or not. Then, a judging section (102) judges whether updating is required or not for the map information set by the setting section (101) to be automatically updated. When the judging section (102) judges that updating is necessary, an updating section (103) updates the map information judged by the judging section (102) to be updated, by downloading data from the external.