clear all;
close all;
clc;
r=5;

img=imread('lena.jpg');
img=double(img);
[m n]=size(img);
imshow(mat2gray(img));

imgn=zeros(m+2*r+1,n+2*r+1);
imgn(r+1:m+r,r+1:n+r)=img;

imgn(1:r,r+1:n+r)=img(1:r,1:n); 
imgn(1:m+r,n+r+1:n+2*r+1)=imgn(1:m+r,n:n+r);
imgn(m+r+1:m+2*r+1,r+1:n+2*r+1)=imgn(m:m+r,r+1:n+2*r+1);
imgn(1:m+2*r+1,1:r)=imgn(1:m+2*r+1,r+1:2*r);

for i=r+1:m+r
    for j=r+1:n+r
        imgn(i,j)=mean(mean(imgn(i-r:i+r,j-r:j+r)));
    end
end

figure;
img=imgn(r+1:m+r,r+1:n+r);
imshow(mat2gray(img));
imwrite(mat2gray(img),'1.jpg');