Patent ID: 7292724

Claim:
An image processing apparatus on which an image forming engine for forming a full color image onto a recording medium by using color materials corresponding to data of color tones on the basis of C (cyan), M (magenta), Y (yellow), and K (black) data is mounted, the image processing apparatus comprising: a color converting component that converts R (red), G (green), and B (blue) data input from the outside to C (1) , M (1) , and Y (1) data which depends on a characteristic of the image forming engine; a lightness acquiring component that acquires lightness from the C (1) , M (1) , and Y (1) data obtained by the conversion of the color converting component; a memory that stores a lightness-gray value characteristic table which depends on the characteristic of the image forming engine, is preset, and indicates gray value balance of the C (1) , M (1) , and Y (1) data with respect to lightness; a gray value reading component that reads a gray value at the lightness acquired by the lightness acquiring component, from the memory; a first arithmetic component that obtains C (2) , M (2) , and Y (2) data by subtracting the gray values read by the gray value reading component from the corresponding C (1) , M (1) , and Y (1) data derived by conversion by the color converting component; a K data generating component that generates K data on the basis of the C (2) , M (2) , and Y (2) data; and a second arithmetic component that calculates C, M, and Y data by subtracting a base amount determined on the basis of the K data generated by the K data generating component from the C (1) , M (1) , and Y (1) data obtained by color conversion by the color converting component.