% =============================================================================
% Math 336 - Image Processing - Laboratory 3
%
% A Matlab script for applying the edge detection filters to the image 
% TSA.jpg.
%
% Marty Kandes
% Department of Physics
% San Diego State University
% Fall 2008
% -----------------------------------------------------------------------------
clear all; close all; clc;
f = imread('tsa.jpg');
f = mat2gray(f);
h = [0,0,0;0,1,0;0,0,0];
g = imfilter(f,h,'replicate');
g = mat2gray(g);
figure;
subplot(1,2,1), imshow(f);
subplot(1,2,2), imshow(g);

clear all; close all; clc;
f = imread('tsa.jpg');
f = mat2gray(f);
h = [0,0,0;0,1,0;0,0,-1];
g = imfilter(f,h,'replicate');
g = mat2gray(g);
figure;
subplot(1,2,1), imshow(f);
subplot(1,2,2), imshow(g);

clear all; close all; clc;
f = imread('tsa.jpg');
f = mat2gray(f);
h = [1,2,1;0,0,0;-1,-2,-1];
g = imfilter(f,h,'replicate');
g = mat2gray(g);
figure;
subplot(1,2,1), imshow(f);
subplot(1,2,2), imshow(g);

clear all; close all; clc;
f = imread('tsa.jpg');
f = mat2gray(f);
k = 8;
h = [-k/8,-k/8,-k/8;-k/8,1+k,-k/8;-k/8,-k/8,-k/8];
g = imfilter(f,h,'replicate');
g = mat2gray(g);
figure;
subplot(1,2,1), imshow(f);
subplot(1,2,2), imshow(g);

clear all; close all; clc;
f = imread('tsa.jpg');
f = mat2gray(f);
k = 4;
h = [-k/8,-k/8,-k/8;-k/8,1+k,-k/8;-k/8,-k/8,-k/8];
g = imfilter(f,h,'replicate');
g = mat2gray(g);
figure;
subplot(1,2,1), imshow(f);
subplot(1,2,2), imshow(g);

clear all; close all; clc;
f = imread('tsa.jpg');
f = mat2gray(f);
k = 6;
h = [-k/8,-k/8,-k/8;-k/8,1+k,-k/8;-k/8,-k/8,-k/8];
g = imfilter(f,h,'replicate');
g = mat2gray(g);
figure;
subplot(1,2,1), imshow(f);
subplot(1,2,2), imshow(g);

clear all; close all; clc;
f = imread('tsa.jpg');
f = mat2gray(f);
k = 8;
h = [-k/8,-k/8,-k/8;-k/8,1+k,-k/8;-k/8,-k/8,-k/8];
g = imfilter(f,h,'replicate');
g = mat2gray(g);
figure;
subplot(1,2,1), imshow(f);
subplot(1,2,2), imshow(g);