clear all;
close all;
orig_imag=imread('Fig2-22a.jpg');
imshow(orig_imag);
%%% add Gaussian Noise
noise_mean=0;
noise_variance=10;
corrupt_imag=imnoise(orig_imag, 'gaussian',noise_mean/255,noise_variance/255);
figure,imshow(corrupt_imag)
%%% Average & Laplacian cascading operation
mask_size=7;
mask_average=fspecial('average',mask_size);
mask_laplacian2=[-1 -1 -1;-1 8 -1;-1 -1 -1];%composite Laplacian mask
corrupt_double=im2double(corrupt_imag);
h1=imfilter(corrupt_double,mask_average,'replicate');% apply averaing filter
h2=imfilter(h1,mask_laplacian2,'replicate');% apply laplacian filter after averaing filter
figure,imshow(h1);
figure,imshow(h2+corrupt_double);
 
%%% Single filter
h=conv2(mask_average,mask_laplacian2); %convolve 2 filters
im_single=imfilter(corrupt_double,h,'replicate');
figure,imshow(im_single+corrupt_double)