Python implementation of the CIEDE2000 Color-Difference Formula.
"The CIEDE2000 Color-Difference Formula: Implementation Notes, Supplementary Test Data, and Mathematical Observations,", G. Sharma, W. Wu, E. N. Dalal, Color Research and Application, vol. 30. No. 1, pp. 21-30, February 2005.
Implementation derived from excel example provided here: http://www2.ece.rochester.edu/~gsharma/ciede2000/
$python tests.py