Color printer calibration with improved color mapping linearity

A color printer including a calibration system, the color printer responsive to printer signals to deposit printer colorants on a medium in accordance with printer signals received, including the steps of:

• means for operating the color printer with printer signals selected to cause the printer to print color samples on the medium;
• means for measuring a colorimetric response at each color sample printed on the medium, and producing a colorimetric signal indicative thereof, mapped to a corresponding printer signal, said colorimetric signals are dispersed through a gamut of the printer at irregular intervals;
• means for preprocessing the colorimetric signals to increase the number thereof with interpolated signals, using interpolation between spatially proximate responses;
• means for mapping the increased number of colorimetric signals to printer signals, to produce a regular interval dispersal of calculated colorimetric signals through color space, each of the calculated colorimetric signals mapped to a corresponding printer signal and derived from the measured colorimetric values and the interpolated values;
• means for storing the mapping in a color conversion memory for use in converting color definitions from a first color space to the printer signals suitable for producing a corresponding response at the color printer.

A color printer including a calibration system, the color printer responsive to printer signals to deposit printer colorants on a medium in accordance with printer signals received, including the steps of:

• a printer controller, controlling printer operation;
• a calibration memory, storing a set of printer signals suitable to drive the printer to print a test sheet;
• a printer, responsive to control signals from the printer controller and the calibration memory to print the test sheet;
• means for measuring the colorimetric response of the printer in printing the test sheet and producing as an output a set of measured colorimetric signals;
• means for mapping measured colorimetric signals to printer signals that caused the printer to print the colorimetric signals;
• a look up table processor, preprocessing the measured colorimetric signals to increase the number thereof with interpolated signals, using interpolation between spatially proximate responses;
• a colorimetic signal interpolation processor producing a regular interval dispersal of calculated colorimetric signals through color space, each of the calculated colorimetric signals mapped to a corresponding printer signal and derived from the measured colorimetric values and the interpolated values;
• a color space conversion memory, storing a lookup table, for use in converting colorimetic signals from a first color space to the printer signals suitable for producing a corresponding response at the printer.