Implement the following Matlab function:

function iml = CV_build_Hough_shape(W)
%
% CV_build_Hough_shape - build Hough shape model
%On input:
%     W (mxn array): binary mask image (shape pixels == 1)
%On output:
%     iml (px2 array): Hough shape model (2D offsets)
%Call:
%  H_circle = CV_build_Hough_shape(W_circle);
%Method:
%    Pick reference point (e.g., point 1); calculate offsets ref-pts
%Author:
%  Your name
%  UU
%  Fall 2012
%