Algorithms for Elevation Reconstruction from Elevation Contour
等高线图的高度恢复算法研究

Algorithms to reconstruct digital elevation map(DEM) from elevation contour is widely used in many applications. In the process of designing a 3D terrain visualization program, where only elevation contour map is available, a new method, region intra interpolation algorithm, was proposed. It utilizes the structural features of elevation contour images, that is, image is partitioned into many regions by elevation contours and each region is only bound to at most 2 elevation values. Therefore each point inside this region can be calculated as a linear interpolation from the two boundary values. The problem then turns into finding the two shortest distances to its bounding elevation contours. Fast realization is also given out, and this speed up also achieved by special design utilizing elevation contour structures to save time on searching for the closest points. Compare with current algorithm like Quadrant Search algorithm, which is design based on a model of random distributing of known value, it shows good performance on both speed and accuracy.