Journal of Electronic ImagingColor spaces for color-gamut mapping
|Format||Member Price||Non-Member Price|
Before doing extensive color gamut experiments, we wanted to test the uniformity of CIE L*a*b*. This paper shows surprisingly large discrepancies between CIE L*a*b* and isotropic observation-based color spaces, such as Munsell: (1) L*a*b* chroma exaggerate yellows and underestimate blues. (2) The average discrepancy between L*a*b* and ideal is 27%. (3) Chips with identical L*a*b* hue angles are not the same color. L*a*b* introduces errors larger than many gamut mapping corrections. We have isotropic data in the Munsell Book. Computers allow threedimensional lookup tables to convert instantly any measured L*a*b* to interpolated Munsell Book values. We call this space ML, Ma, and Mb in honor of Munsell. LUTs have been developed for both LabtoMLab and MLabtoLab. With this zero-error, isotropic space we can return our attention to the original problem of colorgamut image processing.