I want to create regions of interest in multiple images for subsequent classification (in all images at once using the same mean and covariance matrices) and exportation to ArcGIS. So far, I have always merged the geocoded images by creating a mosaic, but due to the size of the images this is no longer possible. I've tried all the hints I've found on the web and in the tutorials, but I can't seem to make it work. Thanks in advance, Wilfried Maps