Error using imwrite to convert .tif files to .jpeg

Hi,

I'm using the following code to convert .tif images to .jpeg

folder = 'D:\CAF\TR coke run Jan 21\';
imageFiles = dir([folder '\Images\*.tif']);
numImages = numel(imageFiles);
Settings        = xml2struct([folder '\settings.xml']); %Converting XML to structure then accessing the number of the samples from the Settings file
NumOfSamples    = str2double(Settings.Children(20).Children.Data);
destinationPath = mkdir([folder '\JPEG Images']);

for i = 1 : 5
    currentImage = fullfile(imageFiles(i).folder, imageFiles(i).name);
    img = imread(currentImage);
    imageName = erase(convertCharsToStrings(imageFiles(i).name),'.tif');
    newName = strcat(folder, 'JPEG Images\', imageName, '.jpg');
    imwrite(img, newName);
end

but I get the following error message:

Error using writejpg (line 46)
Data with 4 components not supported for JPEG files.

Error in imwrite (line 546)
        feval(fmt_s.write, data, map, filename, paramPairs{:});

I know that img is a "1024x1280x4 uint8" variable. Hence, I've tried writing imwrite(img(:,:,i), newName) to get the programme to write them. This works for the first 4 images but stops at the 5th, expectedly.

Is there any way around this?

Thanks in advance

[Walter Roberson]

The files are either RGBA or CMYK - or possibly RGB+NIR. Or possibly even geotiff.

jpeg does not handle transparency (I would need to check jpeg 2000)

CMYK could be converted to RGB

Answer 1

[Matt Gaidica]

JPEG files are only going to be NxMx3. Try:

imwrite(img(:,:,1:3), newName);

If that doesn't work, please supply your TIFF's.

[Teshan Rezel]

this works, thank you!