10 Facts About CIELAB

CIELAB color space, referred to as L*a*b*, is a color space defined by the International Commission on Illumination in 1976.

CIELAB was intended as a perceptually uniform space, where a given numerical change corresponds to a similar perceived change in color.

CIELAB space is three-dimensional, and covers the entire gamut of human color perception.

CIELAB is calculated relative to a reference white, for which the CIE recommends the use of CIE Standard Illuminant D65.

Lightness value, L* in CIELAB is calculated using the cube root of the relative luminance with an offset near black.

CIELAB is less uniform in the color axes, but is useful for predicting small differences in color.

CIELAB coordinate space represents the entire gamut of human photopic vision, and far exceeds the gamut for sRGB or CMYK.

Ideally, CIELAB should be used with floating-point data to minimize obvious quantization errors.

Three coordinates of CIELAB represent the lightness of the color, its position between red and green and its position between yellow and blue .

Hunter Associates Lab discovered that better agreement could be obtained with other color difference metrics, such as CIELAB by allowing these coefficients to depend upon the illuminants.