CIELChab (a.k.a. LCh or HCL) ColorSpace

CIELChab ¹⁾ is a colorspace based on the following coordinates:

• L: lightness: in the range [0, 100]
• C is the polar coordinates of chroma, relative saturation in [0, 230]
• H is the hue angle of the hue in the CIELAB color wheel (degree [0, 360])

CIELChab is also known as:

• CIELCh or LCh for short
• CIEHLC or HLC / HCL for short.

This space is based on CIELAB where C and H are used instead of the Cartesian coordinates a* and b*.

ColorPicker to explore this color space. ²⁾

d3 has an hcl and lch constructor.

const color1 = d3.hcl("#075ebb") // hexadecimal RGB
console.log(`hue: ${color1.h} degree`);
console.log(`c: ${color1.c} `);
console.log(`lightness: ${color1.l} `);