colour.ATD95_Specification

class colour.ATD95_Specification[source]

Defines the ATD (1995) colour vision model specification.

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

Parameters

  • h (numeric or array_like) – Hue angle \(H\) in degrees.

  • C (numeric or array_like) – Correlate of saturation \(C\). Guth (1995) incorrectly uses the terms saturation and chroma interchangeably. However, \(C\) is here a measure of saturation rather than chroma since it is measured relative to the achromatic response for the stimulus rather than that of a similarly illuminated white.

  • Q (numeric or array_like) – Correlate of brightness \(Br\).

  • A_1 (numeric or array_like) – First stage \(A_1\) response.

  • T_1 (numeric or array_like) – First stage \(T_1\) response.

  • D_1 (numeric or array_like) – First stage \(D_1\) response.

  • A_2 (numeric or array_like) – Second stage \(A_2\) response.

  • T_2 (numeric or array_like) – Second stage \(A_2\) response.

  • D_2 (numeric or array_like) – Second stage \(D_2\) response.

Notes

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

References

[Fai13a], [Gut95]

Create new instance of ATD95_Specification(h, C, Q, A_1, T_1, D_1, A_2, T_2, D_2)

__init__()

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

Methods

__init__

Initialize self.

count(value)

index(value, [start, [stop]])

Raises ValueError if the value is not present.

Attributes

A_1

Alias for field number 3

A_2

Alias for field number 6

C

Alias for field number 1

D_1

Alias for field number 5

D_2

Alias for field number 8

Q

Alias for field number 2

T_1

Alias for field number 4

T_2

Alias for field number 7

h

Alias for field number 0