Abstract
A digital elevation model (DEM) with same map projection and spatial resolution as satellite imagery is required for the correction of topographic effect on radiometric and geometric distortion. As the DEM is used to calculate solar incident angles, the spatial derivative of elevation such as slope is an important feature as well as elevation itself. In this paper, we evaluate interpolation methods for resampling the DEM published by Geographical Survey Institute of Japan into UTM coordinate system. From the practical standpoint, we investigate the simple interpolation methods : nearest neighbor, bilinear and cubic convolution. The converted DEM is compared to the original DEM with respect to statistics of slope angle in addition to elevation. It is shown that the cubic convolution is adequate for the resampling because its parameter can control the smoothness and sharpness of the converted image. However, if the finer resolution is required, the bilinear interpolation seems more adequate than cubic convolution.
