Patent ID: 7710597

Claim:
A method for transforming image data values associated with a halftone imaging device, the method comprising: defining a mathematical model based on Neugebauer equations that converts dot size input values for a plurality of printing inks to tristimulus values; defining a dot gain function that converts input dot sizes into adjusted output dot sizes based on a value of a dot gain parameter wherein the dot gain function is characterized by a dot gain parameter value representing a maximum gain for an intermediate input dot size and no gain for minimum and maximum input dot sizes; adjusting dot size values for each dot size input value used in said Neugebauer calculations by means of said dot gain function and said dot gain parameter; determining a single dot gain parameter value, for use in the dot gain function, for each single-colorant Neugebauer primary that characterizes the relationship of dot size input values to measured tristimulus values for each single colorant ink; determining a unique correction value for a dot gain parameter for each single colorant Neugebauer primary associated with printing that single colorant Neugebauer primary on each of the remaining Neugebauer primaries that do not contain said single colorant Neugebauer primary; calculating tristimulus color values as a function of the dot sizes of said plurality of printing inks and the dot gain function to characterize a color response of the halftone imaging device; generating a profile based on the color response of the halftone imaging device; performing one or more of the following steps: adapting color values for use with the halftone imaging device based on the profile; printing the adapted color values on the halftone imaging device; and preparing color values for a different device based on the profile wherein the color values are converted from color values intended for the halftone imaging device.