Patent ID: 7495799
Filing Date: 2009-02-24
Classification: H04N

Abstract:
1. A method comprising: printing samples on print media with at least first and second marking engines; determining a first lightness value of a solid area of a first sample printed with the first marking engine; determining a second lightness value of a solid area of a second sample printed with the second marking engine; comparing the first and second solid area lightness values to one another; based on the comparison, identifying a lighter marking engine and a darker marking engine; determining lightness value of the print media; determining a critical area coverage of the darker marking engine as being directly proportional to a scaled solid area density which is a result of a division of a difference between the first solid area lightness value and the print media lightness value and a difference between the second solid area lightness value and the print media lightness value: adjusting tone reproduction curve of the lighter marking engine to substantially match tone reproduction curve of the darker marking engine.