How to i build a structure like digitTest4DArrayData with OWN data

Hello,

i'd like to use the imageDataAugmenter for my own dataset. To achieve this, i need to create my image database in the

same structure like digitTest4DArrayData has.

My images consist of .png files, listed up in different directories for the labels.

So basically, i want to run the following example code:

[XTrain,YTrain] = digitTrain4DArrayData;
imageSize = [56 56 1];
auimds = augmentedImageDatastore(imageSize,XTrain,YTrain,'DataAugmentation',augmenter)

minibatch = preview(auimds);
imshow(imtile(minibatch.input));

The only difference is that i want to use my own dataset, instead of the testset digitTrain4DArrayData.

How can i achieve this? I did not find any documentation on this issue.

Thank you!

[MARCO]

Hi, I have the same problem. How did you do it?

Answer 1

[Tejas]

Hello Matthias,

To convert your dataset into the same structure as the ‘digitTest4DArrayData' test dataset, use the 'imageDatastore' function, as shown in the code snippet below.

function [XTrain,YTrain] = convertTodigitTrain4DArrayData(rootFolder)
    % Create an imageDatastore to help load and manage the images
    imds = imageDatastore(rootFolder, ...
        'IncludeSubfolders', true, ...
        'LabelSource', 'foldernames', ...
        'FileExtensions', '.png');
    
    % Read all images and their labels
    numImages = numel(imds.Files);
    imageSize = [56 56]; 
    XTrain = zeros([imageSize 1 numImages], 'like', readimage(imds, 1)); 
    YTrain = imds.Labels;
    
    % Resize and load images into the 4D array
    for i = 1:numImages
        img = readimage(imds, i);
        img = imresize(img, imageSize);
        XTrain(:, :, :, i) = img;
    end 
end

To use the 'convertTodigitTrain4DArrayData'function, provide the path to the root directory containing the label subdirectories as the input argument.

[XTrain,YTrain] = convertTodigitTrain4DArrayData('dataset');

For more information on 'imageDatastore', use the following command to access the documentation:

web(fullfile(docroot, "matlab/ref/matlab.io.datastore.imagedatastore.html"))