Gaussian Filter.matlab

A = imread('peppers.png');
G = fspecial('gaussian', [5,5], 2);
GFilter =   fspecial('gaussian', [5,5], 2);
G = imfilter(I, GFilter);
figure;

subplot(141); imshow(A); title('Original Image');
subplot(142); imshow(G); title('Gaussian Filter');
subplot(143); imshow(A-G); title('Difference');
subplot(144); imshow((A-G).^2); title('Difference^{2}');

gistfile1.matlab

I = imread('tire.tif');
figure, imshow(I); figure, imhist(I); figure, imshow(255-I); figure, imhist(255-I); 
figure, histeq(I); figure, imhist(histeq(I));

Median Filter.matlab

I = imread('eight.tif');
J = imnoise(I, 'salt & pepper', 0.1);
K = medfilt2(J);
figure, imshow(I); figure, imshow(J); figure, imshow(K); figure, imshow(I-J); figure, imshow(K-I); figure, imshow((I-K).^(2));