Color-Mixing Correction of Overlapped Colors in Scanner Images

Color mixing occurs between the colors of ink and paper when the former is non-opaque. For non-white paper, even the hue of a figure in such an ink may change. In such cases, color conversion is required to extract only the pattern of a specified ink-color from a document image. In this paper, we consider an effective model of the Yule-Nielsen type with the Beer-Lambert law for scanner images of handwritten forms with ballpoint pens, and propose a new method of correcting color mixing. These parameters are calculated using only the information obtained from a pair of scanner images with different-colored paper and the same ink color. The experimental results confirm the feasibility of this approach.