CIE L*a*b* to Munsell Colour

cie_lab_to_munsell_colour.py

import colour
import numpy as np

# CIE L*a*b* input data
Lab = np.array([79.57, -1.61, 13.05])

# Assumed illuminant used for CIE L*a*b* measurements, could be D65.
illuminant_t = colour.ILLUMINANTS[
    'CIE 1931 2 Degree Standard Observer']['D50']
# Munsell Renotation System illuminant.
illuminant_r = colour.ILLUMINANTS[
    'CIE 1931 2 Degree Standard Observer']['C']

XYZ = colour.Lab_to_XYZ(Lab, illuminant_t)
XYZ_a = colour.chromatic_adaptation_VonKries(
    XYZ, colour.xy_to_XYZ(illuminant_t), colour.xy_to_XYZ(illuminant_r))
xyY = colour.XYZ_to_xyY(XYZ_a)
munsell_colour = colour.xyY_to_munsell_colour(xyY)
print(munsell_colour)
# 7.4Y 7.9/1.6