class colour.Hunt_Specification[source]

Defines the Hunt colour appearance model specification.

This specification has field names consistent with the remaining colour appearance models in colour.appearance but diverge from Fairchild (2013) reference.

  • J (numeric or array_like) – Correlate of Lightness \(J\).
  • C (numeric or array_like) – Correlate of chroma \(C_94\).
  • h (numeric or array_like) – Hue angle \(h_S\) in degrees.
  • s (numeric or array_like) – Correlate of saturation \(s\).
  • Q (numeric or array_like) – Correlate of brightness \(Q\).
  • M (numeric or array_like) – Correlate of colourfulness \(M_94\).
  • H (numeric or array_like) – Hue \(h\) quadrature \(H\).
  • HC (numeric or array_like) – Hue \(h\) composition \(H_C\).


  • This specification is the one used in the current model implementation.


[Fai13f], [Hun04]

Create new instance of Hunt_Specification(J, C, h, s, Q, M, H, HC)


Initialize self. See help(type(self)) for accurate signature.


count Return number of occurrences of value.
index Return first index of value.


C Alias for field number 1
H Alias for field number 6
HC Alias for field number 7
J Alias for field number 0
M Alias for field number 5
Q Alias for field number 4
h Alias for field number 2
s Alias for field number 3