コンピュータマッピングの水深データファイル作成作業への応用

抄録

The Hydrographic Department of Japan has constructed the "Depth data file" for the past several years. Attributes and locations of the point-and line-information included in the nautical chart are numerized and put into the complete chart data base. The point-information includes the depth, the quality of bottom material and so on, and on the other hand, there are the coast line, the contour line and the others in the line-information.
For numerizing a mount of chart data precisely and efficiently, we need some degitizing systems such as scanner and degitizer. Firstly, by using scanner, the accurate information of locations are able to be taken from a mount of chart data. Nextly, by using degitizer, locations are repaired and attributes are put for these data.
We applied the computer mapping technique in Urban Information System developed by our corporation to this degitizing process. On this paper, I will explain how the data files can be constructed more efficiently, in the present processing.