Contraharmonic mean filter

clear all; close all; clc;
f = imread('lena.gif');
f = imnoise(f,'salt & pepper',0.1);
f = im2double(f);
subplot(1,2,1),imshow(f),title('Original Image');
[m n]=size(f);
si=1;Q=0;
for i = 1:m
for j = 1:n
con=0; s1=0; s2=0;
for k1 = i-si:i+si
for p1 = j-si:j+si
if ((k1>0 && p1 >0) && (k1<m && p1<n))
con = con+1;
s1=s1+(f(k1,p1)^Q);
s2=s2+(f(k1,p1)^(Q+1));
end
end
end
b1(i,j)=s2/s1;
end
end
subplot(1,2,2),imshow(b1),title('Cantraharmonic mean filtered');