How to convert rgb to lab??

I used the following function :

rgb = imread('peppers.png');
lab = rgb2lab(rgb);

But i got an error. How to solve this? What is the command that is needed?

[Ahmet Cecen]

What is the exact error? I suspect you simply don't have the toolbox, since the above works for me.

[Darsana P M]

what should i do to get the matlab toolbox in matlab R2013a

Answer 1

[Walter Roberson]

rgb2lab() is in the Image Processing Toolbox from R2014b and later.

For releases before that, use makecform()

[Darsana P M]

can you make it more clear. I could not use makecform() command too

[John D'Errico]

These are tools that were not present in older MATLAB releases. You cannot use them, unless you upgrade MATLAB, as well as the toolbox to newer releases.

[Darsana P M]

How can i upgrade to R2016a from R2013a. Do i need to have the license to access them?

[Walter Roberson]

makecform() was present in the Image Processing Toolbox from R2006a or earlier. If you do not have it then you probably do not have the Image Processing Toolbox.

It is too late now to purchase Image Processing Toolbox for R2013a if you do not already have it.

You will probably need to purchase MATLAB again, with the Image Processing Toolbox.