saltandpeppermedian.m

Image enhancement in frequency domain using Fourier center frequency, Gaussian lowpass filter, Low p

clear all
clc
I=imread('Fig0507(a)(ckt-board-orig).tif');
J=imnoise(I,'salt & pepper',.075);
a=double(J);
b=a;
[row col]=size(a);
for x=2:1:row-1;
    %% To make a 3 x 3 matrix into a 1 x 9 matrix
    for y=2:1:col-1;
        a1=[a(x-1,y-1) a(x-1,y) a(x-1,y+1) a(x,y-1) a(x,y) a(x,y+1) a(x+1,y-1) a(x+1,y) a(x+1,y+1)];
        a2=sort(a1);
        med=a2(5);  %% The fifth value of the median
        b(x,y)=med;
    end
end
figure(1),imshow(uint8(I)),title('Original image');
figure(2),imshow(uint8(J)),title('Original image with salt and pepper Noise');
figure(3),imshow(uint8(b)),title('Noise Reduction using Median Filtering ');