From: Sufiah Ahmad on
ImageAnalyst <imageanalyst(a)mailinator.com> wrote in message <94515bca-ccc6-4c11-819d-639fb8ff1a81(a)x37g2000yqj.googlegroups.com>...
> Read my answer. Did you take one of the individual color channels,
> like the red one, the green one, or the blue one? NO. You STILL
> passed in the color image for some reason. Why do you think you
> extracted the individual color bands -- just for the heck of it?
> Pass in one of those monochrome images (individual color bands or the
> rgb2ind image) and you will be fine.

************************
Thank you ..I got it.
Below is my code.

n =imread('d:nor.jpg');
>> imshow(n);
>> J = rgb2gray(n);
>> figure, imshow(n), figure, imshow(J);
>> figure, imhist(J);