Patent ID: 7319545

Claim:
A color reproduction system with drift correction, comprising: an output device having a set of tone reproduction compensation curves for rendering an image on a recording medium; said output device generating, using said set of tone reproduction compensation curves, an output document having a plurality of color test patches; a scanner for scanning said output document having said plurality of color test patches to generate scanned image data representative of said plurality of color test patches, the scanned image data providing a color representation of said plurality of color test patches; and an image processing system receiving said scanned image data and generating print ready data; said image processing system device including, a calibration target generator to generate, from a set of digital signals, a calibration target, to be printed, representing a plurality of color test patches, a calibration conversion processor to convert the scanned image data into a set of device independent color signals, a calibration processor for computing a set of color shift correction signals by comparing the set of device independent color signals with a set of desired color signals, and an adjustment processor to re-calculate a set of tone reproduction compensation curves in response to said color shift correction signals and to cause said re-calculated set of tone reproduction compensation curves to replace the set of tone reproduction compensation curves in said output device.