DIGITAL PROCESSING TECHNIQUES FOR IMAGE MAPPING WITH LANDSAT TM AND SPOT SIMULATOR DATA.

To overcome certain problems associated with the visual selection of Landsat TM bands for image mapping, the author used a quantitative technique that ranks the 20 possible three-band combinations based upon their information content. Standard deviations and correlation coefficients can be used to compute a value called the Optimum Index Factor (OIF) for each of the 20 possible combinations. SPOT simulator images were digitally processed and compared with Landsat-4 Thematic Mapper (TM) images covering a semi-arid region in northern Arizona and a highly vegetated urban area near Washington, D. C. Statistical comparisons indicate the more radiometric or color information exists in certain TM three-band combinations than in the three SPOT bands.