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% Math 336 - Image Processing - Laboratory 6
%
% Image Morphology (Part 1):
% Implement the grayscale morphological operations.
%
% Marty Kandes
% Computational Science Research Center / Department of Physics
% San Diego State University
% Fall 2008
% -------------------------------------------------------------------------
clear all; close all; clc;                   % Clear Matlab workspace.
F = imread('lena.jpg');                      % Read in the image.
F = im2double(F);                            % Convert image to double.
F = mat2gray(F);                             % Normalize grayscale image.
SE = ones(3,2);                              % Build the structure element.
AP = [2,2];                                  % Set the active point of the SE. 
G = mdilate(F,SE,AP,'gray');                 % Dilate the image F.
G = mat2gray(G);                             % Rescale dilated image G to grayscale.
figure;                                      % Open new figure.
imshow(G);                                   % Display dilated image.
imwrite(G,'lenadilated.jpg','jpg');          % Write dilated image to file.
H = merode(F,SE,AP,'gray');                  % Erode the image.
H = mat2gray(H);                             % Rescale eroded image to grayscale.
figure;                                      % Open new figure.
imshow(H);                                   % Display eroded image.
imwrite(H,'lenaeroded.jpg','jpg');           % Write eroded image to file.
SE = ones(3,3);                              % Build square structure element.
I = mopen(F,SE,AP,'gray');                   % Open image with a square SE.
I = mat2gray(I);                             % Rescale opened image to grayscale.
figure;                                      % Open new figure.
imshow(I);                                   % Display opened image.
imwrite(I,'lenaopenedwithsquare.jpg','jpg'); % Write opened image to file.
SE = ones(3,3);                              % Build disk structure element.
SE(1,1) = 0;                                 %
SE(1,3) = 0;                                 %
SE(3,1) = 0;                                 %
SE(3,3) = 0;                                 %
J = mopen(F,SE,AP,'gray');                   % Open image with a disk SE.
J = mat2gray(J);                             % Rescale opened image to grayscale.
figure;                                      % Open new figure.
imshow(J);                                   % Display opened image.
imwrite(J,'lenaopenedwithdisk.jpg','jpg');   % Write opened image to file.
SE = zeros(3,3);                             % Build L-shaped structure element.
SE(:,1) = 1;                                 %
SE(3,:) = 1;                                 %
K = mopen(F,SE,AP,'gray');                   % Open image with a L-shaped SE.
K = mat2gray(K);                             % Rescale opened image to grayscale.
figure;                                      % Open new figure.
imshow(K);                                   % Display opened image.
imwrite(K,'lenaopenedwithlshape.jpg','jpg'); % Write opened image to file.
SE = ones(3,3);                              % Build square structure element.
L = mclose(F,SE,AP,'gray');                  % Close image with a square SE.
L = mat2gray(L);                             % Rescale closed image to grayscale.
figure;                                      % Open new figure.
imshow(L);                                   % Display closed image.
imwrite(L,'lenaclosedwithsquare.jpg','jpg'); % Write closed image to file.
SE = ones(3,3);                              % Build disk structure element.
SE(1,1) = 0;                                 %
SE(1,3) = 0;                                 %
SE(3,1) = 0;                                 %
SE(3,3) = 0;                                 %
M = mclose(F,SE,AP,'gray');                  % Close image with a disk SE.
M = mat2gray(M);                             % Rescale closed image to grayscale.
figure;                                      % Open new figure.
imshow(M);                                   % Display closed image.
imwrite(M,'lenaclosedwithdisk.jpg','jpg');   % Write closed image to file.
SE = zeros(3,3);                             % Build L-shaped structure element.
SE(:,1) = 1;                                 %
SE(3,:) = 1;                                 %
N = mclose(F,SE,AP,'gray');                  % Close image with a L-shaped SE.
N = mat2gray(N);                             % Rescale closed image to grayscale.
figure;                                      % Open new figure.
imshow(N);                                   % Display closed image.
imwrite(N,'lenaclosedwithlshape.jpg','jpg'); % Write closed image to file.
O = imread('colored_peppers.jpg');           % Read in the colored image.
O = im2double(O);                            % Convert image to double.
SE = ones(3,3);                              % Build a square structure element.
P = mbound(O,SE,AP);                         % Apply boundary extraction.
figure;                                      % Open new figure.
imshow(P);                                   % Display boundary extracted image.
imwrite(P,'peppersboundary.jpg','jpg');      % Write BEI to file.
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