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bundles / skimage 0.26.1rc0.dev0+git20260530.b607368ff / skimage / color / colorconv / rgb2lab

function

skimage.color.colorconv:rgb2lab

source: /dev/scikit-image/src/skimage/color/colorconv.py:1234

Signature

def rgb2lab(rgb, illuminant = D65, observer = 2, *, channel_axis = -1)

Summary

Conversion from the sRGB color space (IEC 61966-2-1:1999) to the CIE Lab colorspace under the given illuminant and observer.

Parameters

rgb : array_like of shape (..., C=3, ...)

The image in RGB format. By default, the final dimension denotes channels.

illuminant : {"A", "B", "C", "D50", "D55", "D65", "D75", "E"}, optional

The name of the illuminant (the function is NOT case sensitive).

observer : {"2", "10", "R"}, optional

The aperture angle of the observer.

channel_axis : int, optional

This parameter indicates which axis of the array corresponds to channels.

Returns

out : ndarray of shape (..., C=3, ...)

The image in Lab format. Same dimensions as input.

Raises

: ValueError

If rgb is not at least 2-D with shape (..., C=3, ...).

Notes

RGB is a device-dependent color space so, if you use this function, be sure that the image you are analyzing has been mapped to the sRGB color space.

This function uses rgb2xyz and xyz2lab. By default Observer="2", Illuminant="D65". CIE XYZ tristimulus values x_ref=95.047, y_ref=100., z_ref=108.883. See function ~.xyz_tristimulus_values for a list of supported illuminants.

Aliases

  • skimage.color.rgb2lab