Combining Panchromatic and Multispeetral Imagery from Dual Resolution Satellite Instruments

Introduction (USDA, 1982). At present photointerpretation of aerial photography is being conSince the launch of Landsat 4 in 1982 sidered for assessing land use and land the scientific community has been procondition. Application of automated techvided with high quality digital images of niques to digital satellite data may be an the earth's surface. In the mid and late effective tool at some future time, 1980s data of 10 m spatial resolution will depending on the quality and cost of be acquired from the Satellite Pour l'Obsatellite data, and the availability of proservation de la Terre (SPOT), and future cedures for extracting the desired assessLandsat satellites will add a 15 m panment of large areas. chromatic band to the current 30 m In this paper a technique is developed Thematic Mapper channels. Such data for combining dual resolution digital data, provide opportunities for detailed obas from SPOT and the planned Thematic servation of processes at the earth's Mappers, to produce high spatial resolusurface, and for mapping of urban areas tion multispectral data. The goal of this and description of land use. As pointed work is essentially equivalent to that of out in a recent paper by Cliche et al. Cliche et al. (1985), except that the anal(1985), the SPOT data may be processed ysis is based on statistical properties in by image enhancement algorithms to yield the data, rather than an ad hoc approach visual products resembling color aerial which seeks an optimum image display. photography. In particular, the analytic approach may Although many applications of such serve as a basis for design of future earth data will involve mapping of urban and observing systems, and the resultant suburban areas, there are possible uses products, representing a reconstruction of requiring both high spatial resolution and high spatial resolution multispectral data large area coverage. For example, each 5 from a sampled data set, are suitable for years the Soil Conservation Service of the further numerical studies, such as comU. S. Department of Agriculture carries puter classification. The basis for the out an inventory of the condition of nontechnique depends on the substantial refederal rural lands in the United States dundancy existing in most high resolution