Converting method for color

Abstract

Abstract PURPOSE:To suitably reproduce the color of an image corresponding to the chromaticity value of an input color signal by employing the chromaticity value corresponding to the case when monochromatic ink, 2-color ink are mixed in equal amounts and maximum amount of achromatic ink is added in hue scale in an equivalent color space. CONSTITUTION:C, M, Y, R, G and B represent chromaticity values of colors corresponding to the maximum densities. Assume that a point (A) is a color actually desired to be expressed, if a point of crossing a half line passing an origin and the point (A) across a hexagon is (B), the quantity of yellow ink is given by a ratio of a segment -(B)M segment -RM when the quantity of magenta ink is 1. If the chromaticity values of the intensity minimum in which maximum mount of black is added to magenta M and red R are M', R' and points of crossing a segment -MR and -M'R' across a half plane (C) representing hue direction are (D), (E), the chromaticity values of the (D), (E) can be easily obtained by an interior dividing method. When the chromaticity value of an image carrier is (F) and the chromaticity value of the case that only black ink is applied at the maximum limit is (G), the quantity of the chromatic ink and the quantity of the achromatic ink can be determined by the interior dividing method.

Inventors

• 👤 Hideaki Mitsutake
• 👤 Hidejiro Kadowaki

Bibliographic Details