exer 14

clear, clc, close all;
img = imread('peter.png');
level = 105;
bwImg = img < level;
holeImg = img .* uint8(bwImg);
subplot(1, 3, 1), imshow(img), title('Original image');
subplot(1, 3, 2), imshow(bwImg), title('Thresholded Image');
subplot(1, 3, 3), imshow(holeImg), title('Binary Map \times Original');
imwrite(bwImg, 'Graylevel_Thresholding_thresholded.png');
imwrite(holeImg, 'Graylevel_Thresholding_blend.png');

exer 15

clear, clc, close all;
img = imread('brain.jpg');
level = graythresh(img);
otsuThresh = round(level * 255);
bwImg = im2bw(img, level);
subplot(1, 4, 1), imshow(img), title('Original image');
subplot(1, 4, 2), imshow(bwImg), title('Globally Thresholded Image');
subplot(1, 4, 3), imshow(1-bwImg .* im2double(img));
title('Overlay');
subplot(1, 4, 4),[counts,x] = imhist(img);
bar(x, counts); hold on;
h = plot(otsuThresh*ones(1,100), linspace(0,max(counts)), 'r-');
title ('Graylevel Histogram');
axis([0 255 0 max(counts)]);
set(gca, 'FontSize', 10);
imwrite(bwImg, 'Globally_Thresholding_bw.png');
saveas(gcf, 'Global_Thresholding_hist.png')

exer 18

clear, clc, close all;
img = imread('fish.png');
level = graythresh(img);
bwImg = 1- im2bw(img, level);
L = bwlabel(bwImg, 8);
rgbLabel = label2rgb(L, 'jet', 'k');
subplot(1, 3, 1), imshow(img), title('Original image');
subplot(1, 3, 2), imshow(bwImg), title('Binarize image');
subplot(1, 3, 3), imshow(rgbLabel); title('Labeled Regions');
imwrite(bwImg, ' Region_Labeling_bw.png');
imwrite(rgbLabel, ' Region_Labeling_rgbLabel.png');