Color Scheme Adjustment by Fuzzy Constraint Satisfaction for Three Types of Color Vision Deficiency

Abstract

We propose a formulation of the problem of color scheme adjustment and a prototype system that automatically solves it, taking into account color vision deficiencies. Our work focuses on the representation of information, such as floor maps of public spaces and figures in books and papers. Color schemes of these representations carry two aspects: the aspect of art design and the aspect of media. The aspect of art design allows the creation of appealing color schemes using the sensitivity to beauty or theme of the contents. The aspect of media, on the other hand, provides information easy to understand. In particular, in the second aspect, designers need to consider universal design. However, these two aspects make any color scheme adjustments difficult, and the optimal combination of colors is not easily determined. The original color scheme made by a designer should not change drastically from the viewpoint of art, and at same time, the scheme must be understandable to everyone even to those with color vision deficiencies. To solve this difficulty posed to designers, we formulate our color scheme adjustment as a fuzzy constraint satisfaction problem, a framework studied in the field of artificial intelligence. In our formulation, we employ the index of color conspicuity, which defines how easily-noticeable a color is for retaining the impression of the original color scheme. To prove the feasibility of the concept, we develop a prototype system in Java that automatically adjusts colors given by a designer.