How to convert a rgb image to CLElab color space?

I need to convert a rgb image to CLElab color space to extract some features.I came across rgb2lab() function which converts rgb image to CIE 1976 L*a*b*.

Is the CIE 1976 L*a*b* same as CLElab color space??I mean is that what i need?

If not, please help me how to convert RGB to CLElab colorspace.

Thank you.

Answer 1

[Guillaume]

I've never heard of CLElab and a quick search doesn't find anything related to colour spaces, so I think you can safely assume that you're looking for CIE Lab, which is commonly just called Lab (or L*a*b*).

So, yes, rgb2lab is the correct function.

Normally you convert to a colour space because it has the properties you need so you should know whether L*a*b* is the actual colour space you want.

Note that RGB is device dependent while L*a*b* isn't, so conversion may not be just as simple as just calling rgb2lab.

[Krishna Chaitanya]

I need to find mean and standard deviation of some regions within the image in CIElab color space.So, you mean, rgb2lab doesn't work in my case?

Do i need to do something else?

Please suggest

Thank you

[Guillaume]

rgb2lab does work and it is probably what you're meant to use.

The point I was trying to make is that the RGB colour space is device dependant, a RGB image on one computer may look different on another (red may look more pink for example). Lab is device independent (iit should look the same everywhere), so when converting between one and the other you should take into account the properties of the rendering device (see options of rgb2lab).However, lots of people ignore that (unfortunately).

[Krishna Chaitanya]

Thank you