I rotated images in preview (mac), but Matlab views original images

Hi

I have tousands if images rotated in preview (mac). I didnt know, what exif is and that some programs - like matlab - view the original, not rotated images. I am trying minimize the damage and I am looking for a fast solution to rotate the images in matlab.

I've tried:

imfinfo('image.jpg')

  struct with fields:

            Filename: 'image.jpg'
         FileModDate: '12-Apr-2021 19:34:46'
            FileSize: 41389
              Format: 'jpg'
       FormatVersion: ''
               Width: 612
              Height: 1101
            BitDepth: 24
           ColorType: 'truecolor'
     FormatSignature: ''
     NumberOfSamples: 3
        CodingMethod: 'Huffman'
       CodingProcess: 'Sequential'
             Comment: {}
         Orientation: 8
         XResolution: 72
         YResolution: 72
      ResolutionUnit: 'Inch'
    YCbCrPositioning: 'Centered'
       DigitalCamera: [1×1 struct] 

so there is information about the orientation. What does the 8 mean?

If i rotate this image, the 'Orientation' information disappears.

xx =  imrotate( image , 90);
imshow(xx)
imwrite(xx, 'test.jpg')

imfinfo('test.jpg')
           Filename: 'test.jpg'
        FileModDate: '16-Apr-2021 12:18:34'
           FileSize: 42262
             Format: 'jpg'
      FormatVersion: ''
              Width: 1101
             Height: 612
           BitDepth: 24
          ColorType: 'truecolor'
    FormatSignature: ''
    NumberOfSamples: 3
       CodingMethod: 'Huffman'
      CodingProcess: 'Sequential'
            Comment: {}

Can I change the 'Orientation' or do something with it to make the images be rotated like in Preview?

Best,

Dawid

[Jan]

"If i rotate this image, the 'Orientation' information disappears." - No, this information vanishes, if you write the image to the disk.

"I have tousands if images rotated in preview (mac)" - What does this mean? I'm not sure if I understand, what your current situation is. Yout can rotate images in the preview of the operating system? Then MacOS writes "8" as orientation? Which value is found there, if you rotate in another direction?

So what exactly are the data you have and what do you want to achieve? What is the relation of your problem to Matlab?

[Rik]

If you want to rotate the actual images themselves, why don't you do that? You can use the orientation property to find out how you need to rotate or flip the image. It takes some experimentation, but it isn't hard.

Answer 1

[Dawid Strzelczyk]

I used this answer: https://www.mathworks.com/matlabcentral/answers/260607-how-to-load-a-jpg-properly?s_tid=srchtitle and solve the problem.

thanks