More specifically, each pixel value has 8 bits for each of red (R), green (G), and blue (B). [0027] In this embodiment, the color monitor 20 is a display device such as a CRT or LCD. The printer 27 is an inkjet printer which discharges and fixes ink droplets of cyan (C), magenta (M), yellow (Y), and black (K) onto a printing medium, and expresses a shade of color by the density.