Image splitting and saving the images separately.

Hi all. Can anyone help me with some tweaking in my code for image splitting and saving the images seperately please? I have the code splitting the image into 2 images but it's displaying 4 images. 2 of them are the images i need and the other 2 are blank. I want to stop the 2 blank images from showing and when saving the images they seem to saving as extremely small images or as just a single pixel.

The code :

clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
workspace;  % Make sure the workspace panel is showing.
fontSize = 20;
for i = [1:10]
    % Read in a standard MATLAB color demo image.
    folder = fullfile(matlabroot, '\Examples\R2019b\vision\MeasuringPlanarObjectsExample\stereo_calibration_test');
    baseFileName = sprintf("temp%05i.jpg", i);%change this to the name of the photo you want to split.
    % Get the full filename, with path prepended.
    fullFileName = fullfile(folder, baseFileName);
    if ~exist(fullFileName, 'file')
        % Didn't find it there.  Check the search path for it.
        fullFileName = baseFileName; % No path this time.
        if ~exist(fullFileName, 'file')
            % Still didn't find it.  Alert user.
            errorMessage = sprintf('Error: %s does not exist.', fullFileName);
            uiwait(warndlg(errorMessage));
            return;
        end
    end
    % Read the image from disk.
    rgbImage = imread(fullFileName);

    % Test code if you want to try it with a gray scale image.
    % Uncomment line below if you want to see how it works with a gray scale image.
    %rgbImage = rgb2gray(rgbImage);

    % Display image full screen.
    imshow(rgbImage);
    % Enlarge figure to full screen.
    set(gcf, 'units','normalized','outerposition',[0 0 1 1]);
    drawnow;
    % Get the dimensions of the image.  numberOfColorBands should be = 3.
    [rows columns numberOfColorBands] = size(rgbImage);

    %==========================================================================
    % The first way to divide an image up into blocks is by using mat2cell().
    blockSizeR = 1080; % Rows in block.
    blockSizeC = 1920; % Columns in block.

    % Figure out the size of each block in rows.
    % Most will be blockSizeR but there may be a remainder amount of less than that.
    wholeBlockRows = floor(rows / blockSizeR);
    blockVectorR = [blockSizeR * ones(1, wholeBlockRows), rem(rows, blockSizeR)];
    % Figure out the size of each block in columns.
    wholeBlockCols = floor(columns / blockSizeC);
    blockVectorC = [blockSizeC * ones(1, wholeBlockCols), rem(columns, blockSizeC)];

    % Create the cell array, ca. 
    % Each cell (except for the remainder cells at the end of the image)
    % in the array contains a blockSizeR by blockSizeC by 3 color array.
    % This line is where the image is actually divided up into blocks.
    if numberOfColorBands > 1
        % It's a color image.
       ca = mat2cell(rgbImage, blockVectorR, blockVectorC, numberOfColorBands);
    else
        ca = mat2cell(rgbImage, blockVectorR, blockVectorC);
    end

    % Now display all the blocks.
    plotIndex = 1;
    numPlotsR = size(ca, 1);
    numPlotsC = size(ca, 2);
    for r = 1 : numPlotsR
        for c = 2: numPlotsC
          %  fprintf('plotindex = %d,   c=%d, r=%d\n', plotIndex, c, r);
            % Specify the location for display of the image.
            %subplot(numPlotsR, numPlotsC, plotIndex);
            % Extract the numerical array out of the cell
            % just for tutorial purposes.
            rgbBlock = ca{r,c};
            imshow(rgbBlock); % Could call imshow(ca{r,c}) if you wanted to.
            [rowsB columnsB numberOfColorBandsB] = size(rgbBlock);
            %imsave(rbgBlock)
            % Make the caption the block number.
            %caption = sprintf('Block #%d of %d\n%d rows by %d columns', ...
              %  plotIndex, numPlotsR*numPlotsC, rowsB, columnsB);
           % title(caption);
            %drawnow;
            % Increment the subplot to the next location.
            plotIndex = plotIndex + i;
            for a = [1:20]
                Folder = 'C:\test';
           
                baseFileName = sprintf("split_image_test%d.png",a);
                image16bit = uint16(24/256);
                imwrite(image16bit, fullfile(Folder,baseFileName));
                pause(2);
          end
        end
    end
end

Answer 1

[Image Analyst]

Next, when you look at what you're writing, it's this:

image16bit = uint16(24/256);
imwrite(image16bit, fullfile(Folder,baseFileName));

so you can see that you're defining image16bit to be a single value, so no wonder it saves as a single pixel. Why did you do that?

If you need anymore help, attach at least one of the "temp%05i.jpg" images.

[Austin Goodall]

Hi Image Analyst,

I'm a student that is currently on an internship with an engineering company. I've not used MATLAB much before -- just some small stuff in university. This is my first time getting to use MATLAB as a tool, so what I know is very basic. I have tried changing the following code to -

baseFileName = sprintf("split_image_test%d.png",a);
imwrite(uint16(24/256), fullfile(Folder,baseFileName));

and I'm getting the same results, i'm a bit lost on how to fix this code, it would be a great learning experience to get this working. also i have attached an "temp%05i.jpg" image below -

[Image Analyst]

You need to split the image into two images and save each one (I guess that's what you want to do):

[rows, columns, numberOfColorChannels] = size(rgbImage); % rgbImage is your original image.
% Extract the left image.
leftImage = rgbImage(:, 1:columns/2, :);
% Save the left image.
baseFileName = sprintf("split_image_test_left%d.png", a);
fullFileName = fullfile(Folder, baseFileName)
imwrite(leftImage, fullFileName);
% Extract the right image.
rightImage = rgbImage(:, columns/2+1:end, :);
% Save the right image.
baseFileName = sprintf("split_image_test_right%d.png", a);
fullFileName = fullfile(Folder, baseFileName)
imwrite(rightImage, fullFileName);

[Austin Goodall]

Thank you, that worked perfectly. I've been stuck on that section of the project for a while now, very much appreciated.