| 摘要 |
PROBLEM TO BE SOLVED: To accurately extract features from aerial photographs. SOLUTION: A polygons representing a road is set, on the basis of a network database 220, and by superposing the polygon on an aerial photograph, the portion corresponding to the road is deleted from the aerial photograph. In this way, processing sections divided by roads are set and, for each processing section, edge extraction and binarization are performed to extract a feature frame. When binarization is performed, a plurality of threshold values are successively used and the thresholds suited to the lightness of the frame parts of the feature are used selectively. Also, extraction rules such as "a wall face is in parallel with the road" are applied. By doing so, accuracy of extraction of the features can be improved. COPYRIGHT: (C)2010,JPO&INPIT |
