Method and system for providing closed loop color control between a scanned color image and the output of a color printer

A system for continuously matching the color of an image read by a color image scanner and the printed hard copy output of a copier or printer controlled by the scanner which comprises:

• a. color gamut means for providing a full scale color gamut based upon preselected parameters such as print media, inks, dyes, drop volumes and pen types,
• b. means for said color gamut means for constructing an initial up table based upon said full scale color gamut and of said initial look up table in memory,
• c. means for a sample test pattern of smaller color gamut information, TP.sub.in, read by a scanner with a test pattern of output information, TP.sub.out, generated by a color printer or color copier to thereby generate a corresponding transformation factor, H, and
• d. means for utilizing said transformation matrix, H, to continuously update said initial look up table, so that the color differences between the image scanned by said color scanner and the hardcopy output of a color printer or copier are always driven towards zero, corrected and minimized.

A method for matching the color of an image read by a color image scanner and the printed hardcopy output of a copier or printer controlled by the scanner, which comprises the steps of:

• a. constructing an initial look up table based upon a full scale color gamut and storing said initial look up table in a computer,
• b. providing a small scale color gamut which is significantly less in size than the size of said full scale color gamut,
• c. scanning said small scale color gamut to thereby generate a sample test pattern of input information, TP.sub.in,
• d. generating a test pattern of output information, TP.sub.out, at the output of a color printer or copier to in turn generate a corresponding transformation matrix, H, in the equation TP.sub.in =H.multidot.TP.sub.out, and
• e. utilizing and processing said transformation matrix, H, to continuously update said initial look up table, so that the color differences between the image scanned by said color scanner and the hardcopy output of a color printer or color copier are always minimized.

A system for matching the color of an image read by a color image scanner and the printed hardcopy output of a copier or printer controlled by the scanner including, in combination:

• a. means including an initial look up table based upon a full scale color gamut and means for storing said initial look up table in a computer,
• b. means for providing a small scale color gamut which is significantly less in size than said full scale color gamut,
• c. means for scanning said small scale color gamut and thereby generating a sample test pattern of input information, TP.sub.in,
• d. means connected to said computer for providing a test pattern of output information, TP.sub.out, and generated by a color printer or copier to in turn generate a corresponding transformation matrix, H, where H is defined by the equation TP.sub.in =H.multidot.TP.sub.out, and
• e. means connected to said color printer and operable to receive said transformation matrix, H, and being further operative to continuously update said initial look up table, so that the color differences between the scanned image read by said color scanner and the hardcopy output of a color printer or color copier are always minimized.