colour.colour_rendering_index

colour.colour_rendering_index(sd_test: SpectralDistribution, additional_data: Literal[False] = False, method: Literal['CIE 1995', 'CIE 2024'] | str = 'CIE 1995') → float

colour.colour_rendering_index(sd_test: SpectralDistribution, additional_data: Literal[True], method: Literal['CIE 1995', 'CIE 2024'] | str = 'CIE 1995') → ColourRendering_Specification_CRI

colour.colour_rendering_index(sd_test: MultiSpectralDistributions, additional_data: Literal[False] = False, method: Literal['CIE 1995', 'CIE 2024'] | str = 'CIE 1995') → NDArrayFloat

Compute the Colour Rendering Index (CRI) \(Q_a\) of the specified spectral distribution.

Parameters:

• sd_test (SpectralDistribution | MultiSpectralDistributions) – Test spectral distribution. A colour.MultiSpectralDistributions of N test illuminants is also accepted, in which case additional_data must be False and the return value is a numpy.ndarray of N \(Q_a\) values.

• additional_data (bool) – Whether to output additional data.

• method (Literal['CIE 1995', 'CIE 2024'] | str) – Computation method.

Returns:

Colour Rendering Index (CRI).

Return type:

float, numpy.ndarray or colour.quality.ColourRendering_Specification_CRI

References

[OD08]

Examples

>>> from colour import SDS_ILLUMINANTS
>>> sd = SDS_ILLUMINANTS["FL2"]
>>> colour_rendering_index(sd)
np.float64(64.2337241...)