Why is matlab seeing images rotated?

Hi,

I'm trying to do some image analysis but I noticed matlab is seeing my images rotated by 90 degrees clockwise. Here is imfinfo:

ans = 

  struct with fields:

            Filename: 'C:\Users\janko\OneDrive\MUNI\Bakalářka\fotky_k_analyze\DSC_7967.jpg'
         FileModDate: '08-Dec-2022 16:52:46'
            FileSize: 1479464
              Format: 'jpg'
       FormatVersion: ''
               Width: 6000
              Height: 4000
            BitDepth: 24
           ColorType: 'truecolor'
     FormatSignature: ''
     NumberOfSamples: 3
        CodingMethod: 'Huffman'
       CodingProcess: 'Sequential'
             Comment: {}
                Make: 'NIKON CORPORATION'
               Model: 'NIKON D5300'
         Orientation: 8
         XResolution: 300
         YResolution: 300
      ResolutionUnit: 'Inch'
            Software: 'Ver.1.03 '
            DateTime: '2022:12:08 16:52:45'
    YCbCrPositioning: 'Centered'
       DigitalCamera: [1×1 struct]
             GPSInfo: [1×1 struct]
       ExifThumbnail: [1×1 struct]

in Windows explorer, it's seen as width = 4000 and Height = 6000. Why is there this difference and how can I force matlab to see them right?

Answer 1

[Image Analyst]

Notice the Orientation field. It's 8, indicating the camera was rotated when the photo was snapped. Some programs read that field and automatically rotate the image for you before displaying it. Other programs, like MATLAB don't. You can use functions like imrotate, flipud, or fliplr to get the image in an orientation you want. Hopefully all your photos have the same orientation field, because I'm not sure off the top of my head to read the orientation flag (might be imfinfo ??).

[Jan]

Thanks, I didn't know that. Yes, I have all of them rotated in same direction

Answer 2

[DGM]

See this thread:

https://www.mathworks.com/matlabcentral/answers/1861338-find-width-and-height-of-jpg-image

Attached is an updated version of the function used for reading the images. This should automatically rotate/flip the image as implied by the orientation tag.

[Jan]

thanks, I'll take a look!