An image processing method to reduce streaking on a printed sheet uses a
negative feedback system to reduce streaking. The method scans a printed
sheet to produce image data. The method further measures gray-levels of
the image data and computes a compensation vector from the measured
gray-levels as the difference between a nominal tonal-resproduction-curve
and local tonal-reproduction-curves. The compensation vector is applied
the image data to be printed. The compensation vector emphasizes ranges
of frequencies sensitive of the human eye.