Try this:
clc; % Clear the command window.
fprintf('Beginning to run %s.m ...\n', mfilename);
close all; % Close all figures (except those of imtool.)
clear; % Erase all existing variables. Or clearvars if you want.
workspace; % Make sure the workspace panel is showing.
format long g;
format compact;
%Division Option
DO=8;
%Defect Color Threshold
colorThreshold=60;
% Specify folder.
folder = fullfile(pwd, 'Image sample');
% Assume all files in folder are to be stitched together.
defaultValues = {'8', '1'};
[pics] = inputdlg({'How many pictures were taken in x direction?','How many pictures were taken in y direction?'},...
'Size of concacenated image', [1 51; 1 51], defaultValues);
x=double(string(pics{1,1}));
y=double(string(pics{2,1}));
% Get all filenames:
filePattern = fullfile(folder, '*.tif');
fileList = dir(filePattern);
fileNames = {fileList.name}
loopCounter = 1;
fullFileName = fullfile(folder, fileNames{loopCounter});
thisImage = imread(fullFileName);
[rows, columns, numberOfColorChannels] = size(thisImage);
% Preallocate output image.
stitchedImage = zeros(y * rows, x * columns);
% Do the stitching.
for row = 1 : y
thisRow = (row - 1) * rows + 1;
for col = 1 : x
thisColumn = (col - 1) * columns + 1;
% Read in this image.
fullFileName = fullfile(folder, fileNames{loopCounter});
thisImage = imread(fullFileName);
thisImage=double(thisImage);
% Paste onto canvass.
stitchedImage(thisRow : (thisRow + rows - 1), thisColumn : (thisColumn + columns -1), :) = thisImage;
% Increment file counter.
loopCounter = loopCounter + 1;
end
end
subplot(2, 1, 1);
imshow(stitchedImage, [])
impixelinfo
title('Original Stitched Image', 'FontSize', 17);
axis('image', 'on');
binaryImage = stitchedImage < colorThreshold;
subplot(2, 1, 2);
imshow(binaryImage)
axis('image', 'on');
g = gcf;
g.WindowState = 'maximized';
% Compute area fraction.
areaFraction = nnz(binaryImage) / numel(binaryImage)
caption = sprintf('Binary Image. The Area fraction for a threshold of %.1f is %.4f.', colorThreshold, areaFraction);
title(caption, 'FontSize', 17);
message = sprintf('The Area fraction for a threshold of %.1f is %.4f.', colorThreshold, areaFraction);
fprintf('%s\n', message);
fprintf('Done running %s.m.\n', mfilename);
uiwait(helpdlg(message));
