Spatial enhancement of elevation data using a single multispectral image
Mark J. Carlotto · Optical Engineering · 2000
A new method for enhancing the spatial resolution of low- resolution digital elevation models (DEMs) using a single higher- resolution multispectral image is described. The method uses a nonlin- ear estimation algorithm to determine an empirical relationship between the spectral response of a pixel and the gradient or slope of its underly- ing elevation surface. This relationship is, in effect, the inverse of the reflectance map used in shape-from-shading to recover surface orienta- tion from image brightness. However, unlike most shape-from-shading techniques, we do not assume constant albedo, nor do we assume a particular functional form for the reflectance map. A depth-from-gradient algorithm is used to generate high-resolution elevations from high- resolution gradients using the low-resolution elevations as boundary val- ues. Experimental results demonstrate the ability to generate enhanced resolution elevation maps from global 1-km DEMs and Landsat Thematic Mapper imagery. © 2000 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(00)02402-8)