COMPUTER GRAPHICS AND REMOTE SENSING - A SYNTHESIS FOR ENVIRONMENTAL PLANNING AND CIVIL ENGINEERING

Abstract

This paper presents efforts undertaken in the field of photo-realistic visualization of natural landscapes using digital elevation models (DEM) and images generated by remote sensing techniques. The remote sensing systems used in this work include Landsat Thematic Mapper, SPOT HRV and aerial photographs. After an appropriate preprocessing, including radiometric corrections and image enhancement procedures, a precise geometric correction is performed in order to achieve a very high co-registration of the images with the elevation model. A mosaic of several images at various resolutions is stored together with the DEM in a data set covering an extensive area. These data are then input to an efficient hardware-independent terrain rendering algorithm based on a forward projection. Atmospheric effects can be simulated. The concept of a virtual scene allows an automated embedding of raytraced 3D objects. The results show that these methods can be used in the field of environmental planning, civil engineering and other applications where terrain visualization is required.