How to change image size from 224 x 224 x 1 to 224 x 224 x 3

i have images with 224 x 224 x 1 size i want to convert it to 224 x 224 x 3

Answer 1

[Kevin Holly]

Img = rand(224,224,1);
imshow(Img)

new(:,:,1) = Img;
new(:,:,2) = Img;
new(:,:,3) = Img;
imshow(new)

size(Img)

ans = 1×2

224 224

size(new)

ans = 1×3

224 224 3

[abdullah al-dulaimi]

broth i have path with 200 images , how can i convert all images in one time

[Kevin Holly]

folder = uigetdir;
files = dir(fullfile(folder,'*.png'));
for ii = 1:length(files)
    grayImage = imread(fullfile(folder,files(ii).name));
    rgbImage = cat(3, grayImage, grayImage, grayImage);
    imwrite(rgbImage,[fullfile(folder,files(ii).name) '_rgb.png'])
end

Answer 2

[Walter Roberson]

I recommend that you consider using an imageDatastore followed by an augmentedImageDatastore -- the augmented store can automatically resize your images and can automatically convert to RGB or grayscale.

[Rev]

How do you do that?

[Walter Roberson]

unzip('MerchData.zip');
imds = imageDatastore('MerchData', ...
    'IncludeSubfolders',true, ...
    'LabelSource','foldernames'); 
augds = augmentedImageDatastore([224 224], imds, 'ColorPreprocessing', 'gray2rgb');
[imdsTrain,imdsValidation] = splitEachLabel(augds,0.7);

and so on.