| 摘要 |
PROBLEM TO BE SOLVED: To perform color signal conversion taking full advantage of a color gamut by having an input-side color gamut and an output-side color gamut determined in advance.SOLUTION: A color saturation ratio calculation unit 108 calculates, as a function of brightness and hue, a color saturation ratio obtained by the output-side color saturation calculated by a color saturation/hue calculation unit 107 by an input-side color saturation calculated by a color saturation/hue calculation unit 106. An abmagnification determination unit 105 calculates a magnification of chromaticity a, bin the chromaticity diagram of an Labcolorimetric system by using the color saturation ratio, as well as a color saturation Cand a hue h supplied from a hue/color saturation calculation unit 104. An abexpansion unit 109 expands the color gamut of actual video by multiplying each coordinate value of the chromaticity a, bin the chromaticity diagram of the Labcolorimetric system by the magnification determined by the abmagnification determination unit 105. By having an input-side color gamut and an output-side color gamut determined in advance, it is possible to determine a magnification for color gamut expansion according to the brightness and hue of an input color video signal. |
