How to save the output of a loop with sequential file numbers.

I am trying to save the output of a simple face detector. I have a group image with multiple faces and want to store cropped images of each face individually, as well as a rotated version of the image. This is a simplified version of the code I am implementing and would be very grateful if someone could help me write the two output images (face_crop and imrotate) to one folder. The file names do not matter. Thank you!

I = imread('my group image')

% bounding_box is size 50
bounding_box = step(vision.CascadeObjectDetector(), I)

for i:size(bounding_box, 1)
    
    % Save this image as 01.jpg (then 03, 05, 07 .... 99)
    face_crop = imcrop(I, [227,227])
    >>>
    
    % Save this image as 02.jpg (then 04, 06, 08 .... 100)
    imrotate = (face_crop, 5, 'bilinear')
    >>>
end

[Stephen]

https://www.mathworks.com/help/matlab/import_export/process-a-sequence-of-files.html

https://www.mathworks.com/help/matlab/ref/imwrite.html

Answer 1

[Thorsten]

for i:size(bounding_box, 1)
    face_crop = imcrop(I, [227,227])
    filename = sprintf('%02d.jpg', 2*i - 1);
    imwrite(face_crop, filename);
    
    face_rot = imrotate(face_crop, 5, 'bilinear');
    filename = sprintf('%02d.jpg', 2*i);
    imwrite(face_rot, filename);
end