I am struggling to get this code to work.

Im unsure of which parameters to change to stitch the image to get the code to work. I have attached the 2 codes in the question as well as a sample set of images

Answer 1

[Image Analyst]

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));

[Martin Olowe]

willi need to change any variables? I have images consisting of 153 tiles to be stitched

[Image Analyst]

You'll need to change the number of rows and columns of course. And I haven't tested it for the case where you have multiple rows and you only have enough images to fill up a partial row. So that may need to be checked and made more robust. Just give it a try and adapt as needed.

Answer 2

[Walter Roberson]

You might be interested in using montage(). The output of montage() is an image() object that you can get the CData for, and the CData will be the composite image.

[Image Analyst]

Yes, or imtile() introduced in r2018b.