Regarding Image Processing - nlfilter, blockproc, colfilt

Hi all, I'm currently running a script that requires a sliding window through an image. For each window, I have to compute the histogram equalization to apply to it.

I've explored nlfilter, blockproc and colfilt for this purpose.

When I executed nlfilter in this manner:

fun=@(x)histeq(x(:));
A=nlfilter(B,[3 3],fun);

It says that: Assignment has more non-singleton rhs dimensions than non-singleton subscripts.

And when I try to run blkproc():

fun=@histeq;
b=blkproc(B,[3 3],fun);

While the code runs well, but the end result is not what i am supposed to get, it sort of outlines the edges for some reason.

I believe its possible to run nlfilter with a sliding window based on histeq from each window, but I just cannot figure out whats going wrong.

Just a question, i read that colfilt is unable to accept histeq as function, is it true?

Thanks guys for your advice. Much appreciated.

Regards Corse