Pixel values from multiple images

Hello Everyone,

I have a bunch of greyscale images. All are resized 50 * 50. All are located in the same folder.

I want to extract the matrix of all pixel values of the images into multipe exel spreadsheets (one sheet for each image).

How could I do it automatically for all images at once?

thanks

Answer 1

[Image Analyst]

FAQ: https://matlab.fandom.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

% Specify the folder where the files live.
myFolder = 'C:\Users\yourUserName\Documents\My Pictures';
% Check to make sure that folder actually exists.  Warn user if it doesn't.
if ~isfolder(myFolder)
    errorMessage = sprintf('Error: The following folder does not exist:\n%s\nPlease specify a new folder.', myFolder);
    uiwait(warndlg(errorMessage));
    myFolder = uigetdir(); % Ask for a new one.
    if myFolder == 0
         % User clicked Cancel
         return;
    end
end
% Get a list of all files in the folder with the desired file name pattern.
filePattern = fullfile(myFolder, '*.png'); % Change to whatever pattern you need.
theFiles = dir(filePattern);
xlsFullFileName = fullfile(myFolder, 'Results.xlsx') % Whatever....
for k = 1 : length(theFiles)
    baseFileName = theFiles(k).name;
    fullFileName = fullfile(theFiles(k).folder, baseFileName);
    fprintf(1, 'Now reading %s\n', fullFileName);
    % Now do whatever you want with this file name,
    % such as reading it in as an image array with imread()
    imageArray = imread(fullFileName);
    imshow(imageArray);  % Display image.
    drawnow; % Force display to update immediately.
    [~, sheetName, ext] = fileparts(baseFileName);
    writematrix(imageArray, xlsFullFileName, sheetName);
end

[Amir Nejati]

Thank you for the code.

I am receiving this error:

Error using writematrix (line 191)
Wrong number of arguments. A filename must be provided when supplying additional parameters, and each parameter name must
be followed by a value.