Change Detection with GRASS GIS – Comparison of images taken by different sensors

Abstract

Images of American military reconnaissance satellites of the Sixties (CORONA) in combination with modern sensors (SPOT, QuickBird) were used for detection of changes in land use. The pilot area was located about 40 km northwest of Yemen’s capital Sana’a and covered approximately 100 km2 . To produce comparable layers from images of distinctly different sources, the moving window technique was applied, using the diversity parameter. The resulting difference layers reveal plausible and interpretable change patterns, particularly in areas where urban sprawl occurs. The comparison of CORONA images with images taken by modern sensors proved to be an additional tool to visualize and quantify major changes in land use. The results should serve as additional basic data eg. in regional planning. The computation sequence was executed in GRASS GIS.