Patent ID: 7457015

Claim:
A computer operable method of processing cyan, magenta, and yellow color values C 1 , M 1 , Y 1 , comprising: receiving input values C 1 , M 1 , Y 1 , K 1 through use of input means; transforming the C 1 , M 1 , Y 1 color values to continuous tone data of the color values cyan, magenta, and yellow color values C, M, Y through use of the value K 1 in such a manner that each of C, M, Y is not greater than a predetermined maximum value VMAX; obtaining blue, cyan, and magenta output color values by setting B=0, Cout=C, and Mout=M; if the sum C+M is greater than VMAX, obtaining blue, cyan and magenta output color values B, Cout, Mout such that B+Cout+Mout=VMAX half-toning B, Cout, Mout and Y using a first threshold array A 1 for B, Cout, and Mout, and a second threshold array A 1 ′ for Y, wherein the second threshold array A 1 ′ is a replica of the first threshold array A 1 that is shifted in at least one of a horizontal/vertical, left/right, or up/down direction relative to the first threshold array A 1 by one pixel.