1 REGRESSION REGRESSION This task computes the best least square linear regression between two images. It uses as input a cross histogram of the two images which must have been created previously by program HISTO_CROSS. 2 IN$ TASK\FILE "Input cross histogram" IN$ The name of the input cross histogram (usually created by HISTO_CROSS). 2 THRESHOLD$ TASK\REAL "Pixel threshold" THRESHOLD$ The minimum number of pixels, below which data are not considered. 1 END