Patent ID: 7864387

Claim:
A method for mapping a colorimetry color space to an input color space for an image forming device, the method comprising: (i) determining target colorimetry values defining a target colorimetry space; (ii) forming, by the image forming device, output colors from initial device color values, (iii) measuring the output colors to produce corresponding initial reference colorimetry values of an initial reference colorimetry space based on the initial device color values, the initial reference colorimetry values and the initial device color values defining a forward model of the image forming device; (iv) determining a penalty error between the target colorimetry values and the reference colorimetry values based on a penalty function, the penalty function being a function of a plurality of variables, the plurality of variables including at least one of C, M, and Y; (v) selecting subsequent device color values to generate refined reference colorimetry values from the forward model that minimizes the penalty error; (vi) constraining the penalty function by constraining selected subsequent device color values to generate constrained subsequent device color values that satisfy a color separation constraint, the constrained subsequent device color values inscribing a contour on the penalty function, wherein the color separating constraint is a radius constraint and defined by K, where K=(C^2+M^2+Y^2)^(1/2); (vii) repeating steps (iv) to (vi) until the penalty error is less than a predetermined value; and (viii) storing in memory the target colorimetry values of the target colorimetry space in association with the corresponding most recent device color values.