コンターの隣接関係を用いた等高線画像の復元処理

抄録

The process to obtain DEM (digital elevation model) from contours drawn on paper map relies on manual operations very heavily. Especially, restoration of extracted contours requires quite amount of time for human operator, and has been one of the most serious burden in the process.
In the previous researches, there had been proposed several methods to reduce the burden. However, they mainly focus on the geometrical relations between individual ending points in local perspective, which resulted in very limited success.
In this paper, a new restoration method based on the adjoining property between contours is proposed. In this approach, virtual elevations are assigned for each contour segments by using the fact that the adjoining contours has a same elevation or an elevation of unit difference. And by restoring the contours of same virtual elevation, the restoration efficiency could be improved quite largely.
The result of experiments shows that 94% of the ending points could be restored by the proposed method, while only 52% could be restored when geometric relations between individual ending points only is used.