To produce a high quality image while minimizing the total quantity of coloring matter, e.g. ink being used and the perceptible roughness of a print image in a digital printer using a plurality of coloring matters of the same color.
When a digital image having at least one color channel including pixels is reproduced using a digital printer having a set of coloring matters, more than one coloring matter in the set has the substantially same color and a different density. An input code value for a specific color channel is used for controlling the quantity of more than one coloring matter and a lookup table for generating a coloring matter control signal corresponding to individual coloring matter is formed for each coloring matter as a function of the input code value. In order to judge the coloring matter control signal, the lookup table is addressed for each pixel of the digital image and the printer is controlled using the coloring matter control signal at the time of reproducing the image thus controlling the quantity of more than one coloring matter respectively.
SPAULDING KEVIN E
MILLER RODNEY L
