calculate blur kernel from original and blurry images

If you are in the situation in which you have the original image ( or an image which is very close to the original - for example in successive frames of a video) than you can use this function to get a good estimate of the blur kernel much faster than working with the blurry image only.
there is a simple demo that should work out of the box .
let me know if there is any problems with this :)
%purpose:
% estimate quickly and effectively the kernel that was used to blur img_orig
% into img_blurred.
% method:
% This function treats the kernel as the solution to an over-constrained
% problem. In other words :
% 1) blurred image = original image ** blur kernel ; where ** = convolution
% 2) hence for each pixel:
% blurred image(i,j) = original image( neighborhood(i,j) .* blur kernel)
% 3) a set of equations (2) can be set for different i,j's to solve for
% the blur kernel.
% 4) there are many many more equations than needed to solve for the blur
% kernel
% A variation of the ransac algorithm is implemented in order to
% find a good estimate of the blur kernel.
kind regards,
dan