separating a color image from its background

Hello! I have a color image with a mole and a background of any color (not black), I wonder if there is any way I can remove the background image to work with. What I need is to read for example the amount of brown out there on the mole but I want no background data appear. Anyone know of any way? Thank you.

Answer 1

[Image Analyst]

I know of several ways. See my File Exchange: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862 for demos that you can adapt to your image.