抄録
A new contour/grid conversion method is proposed which is based on smoothing filter. By applying the smoothing filter to the contour image repeatedly, the image is gradually changed to target grid data.
The implementation of this algorithm is extremely simple, because the algorithm only requires 3×3 masking operation. Also, the proposed method can be applied to contour image with cut lines. This feature is important in reducing the work burden because generating a complete contour image automatically is almost impossible and generally requires much efforts for experienced human operator.
To compare the performance of the proposed method with previously reported methods, several algorithms which satisfy the simple implementation condition is actually implemented. In the experiment, the proposed algorithm showed best performance in maximum error. Also, it was most stable for contours with cut lines. Even though the result for average error was not the best, the error was 71cm for contours with lOm elevation interval, which is thought to be sufficient for practical use in many applications.
