cover_window( inp_img,w )

get the neighbor array from single pixel in the array

All the filters have needed neighbor data from the current pixel in the image,here this function(res_window=cover_window(how many neighbor value for row ,how many neighbor value for column ,input image) produce the result( res_window(row,col,total size))
%%
%input
%inp_img=2d data(row * col)
%w=cover size
%w=[3 3] = 3x3 cover pixel generation
%output
%o_img=result 3d
%o_img(w(1),w(2),r*col)
% if
% inp_img=[1 2 3; 4 5 6;];
% w=[3 3];
% Soloution
% it will construct new image
% new_img=[0 0 0 0 0;0 1 2 3 0;0 4 5 6 0;0 0 0 0 0]
% result
% o_img(:,:,1)=[0 0 0;0 1 2;0 4 5]
% o_img(:,:,2)=[0 0 0;1 2 3;4 5 6]
%finally
% o_img(1:3,1:3,6)
% example
a=imread('pears.png');
b=rgb2gray(a);
c=cover_window( b,[3 3]); %%3x3 window construction
%