colour.constants.cie Module¶

CIE Constants¶

Defines CIE constants.

colour.constants.cie.CIE_E = 0.008856451679035631¶

CIE \(\epsilon\) constant.

CIE_E : numeric

Notes

• The original CIE value for \(\epsilon\) is \(\epsilon=0.008856\), Bruce Lindbloom has shown that this value is causing a discontinuity a the junction point of the two functions grafted together to create the Lightness \(L^*\) function.

  That discontinuity can be avoided by using the rational representation as follows: \(\epsilon=216/24389\).

References

[1]	http://brucelindbloom.com/index.html?LContinuity.html (Last accessed 24 February 2014)

colour.constants.cie.CIE_K = 903.2962962962963¶

CIE \(k\) constant.

CIE_K : numeric

Notes

• The original CIE value for \(k\) is \(k=903.3\), Bruce Lindbloom has shown that this value is causing a discontinuity a the junction point of the two functions grafted together to create the Lightness \(L^*\) function.

  That discontinuity can be avoided by using the rational representation as follows: \(k=24389/27\).

References

[2]	http://brucelindbloom.com/index.html?LContinuity.html (Last accessed 24 February 2014)