colour.contrast.maximum_angular_size_Barten1999

colour.contrast.maximum_angular_size_Barten1999(u, X_0=60, X_max=12, N_max=15)[source]

Returns the maximum angular size \(X\) of the object considered using Barten (1999) method.

Parameters:
  • u (numeric) – Spatial frequency \(u\), the cycles per degree.
  • X_0 (numeric or array_like, optional) – Angular size \(X_0\) in degrees of the object in the x direction.
  • X_max (numeric or array_like, optional) – Maximum angular size \(X_{max}\) in degrees of the integration area in the x direction.
  • N_max (numeric or array_like, optional) – Maximum number of cycles \(N_{max}\) over which the eye can integrate the information.
Returns:

Maximum angular size \(X\) of the object considered.

Return type:

numeric or ndarray

References

[Barten1999], [Barten2003], [Cowan2004], [InternationalTelecommunicationUnion2015],

Examples

>>> maximum_angular_size_Barten1999(4)  # doctest: +ELLIPSIS
3.5729480...