Color-naming system using fuzzy set theoretical approach

Abstract

This paper considers a fuzzy system in which vague colors can be expressed in words (usually adjectives). The words (color names) consist of a hue name with its modifier, or a hue name only. This system can translate input hue system data to color names (output). Triangular membership functions are applied to the hue angle, and conical membership functions are applied to the relationship between lightness and saturation. By treating the membership function of tone modifier as a fuzzy relation between lightness and saturation, we can easily obtain the membership grade of a target modifier as an output fuzzy set from projection of an input fuzzy set. Three modifiers associated with respective grades indicate vague colors. The present paper proposes a fuzzy system that can determine a few tone modifiers (e.g., dark, dull, deep, etc.) suitable for color names in common use. For system evaluation, vague colors for 5 principal hues, 124 boundary points among neighboring JIS modifiers are used.