how to write metadata information to a jpg file

Hello,

I'm reading in .JPG files taken with a Phantom 4pro drone. These files have the following meta data that I can grab with "imfinfo":

Filename: '/Volumes/Utumno/Chile_2016/SG-161018-51m_images_only/101MEDIA/DJI_0112.JPG'
         FileModDate: '18-Oct-2016 10:33:46'
            FileSize: 5672512
              Format: 'jpg'
       FormatVersion: ''
               Width: 4000
              Height: 3000
            BitDepth: 24
           ColorType: 'truecolor'
     FormatSignature: ''
     NumberOfSamples: 3
        CodingMethod: 'Huffman'
       CodingProcess: 'Sequential'
             Comment: {}
    ImageDescription: 'DCIM\101MEDIA\DJI_0112.JPG'
                Make: 'DJI'
               Model: 'FC330'
         Orientation: 1
         XResolution: 72
         YResolution: 72
      ResolutionUnit: 'Inch'
            Software: 'v01.19.5266'
            DateTime: '2016:10:18 10:33:43'
    YCbCrPositioning: 'Centered'
       DigitalCamera: [1×1 struct]
             GPSInfo: [1×1 struct]
         UnknownTags: [3×1 struct]
       ExifThumbnail: [1×1 struct]

I am manipulating these images and want to save them back out as a JPG with the same metadata that they strated with. However, when I save back out as a JPG the only metadata I can get to save are the following fields:

        Filename: '/Volumes/Utumno/Chile_2016/SG-161018-51m_images_only/101MEDIA/rad_corr/test.JPG'
        FileModDate: '23-Feb-2019 16:55:09'
           FileSize: 2666899
             Format: 'jpg'
      FormatVersion: ''
              Width: 4000
             Height: 3000
           BitDepth: 24
          ColorType: 'truecolor'
    FormatSignature: ''
    NumberOfSamples: 3
       CodingMethod: 'Huffman'
      CodingProcess: 'Sequential'
            Comment: {}

which means I'm missing the latter 14 fields. How can I save this ancillary information with my newly manipulated JPGs?

thanks!

Answer 1

[Stephen23]

https://www.mathworks.com/matlabcentral/answers/152559-writing-exif-data-to-jpg

https://www.mathworks.com/matlabcentral/fileexchange/42000-run_exiftool

Also:

https://www.mathworks.com/matlabcentral/answers/299542-how-to-preserve-image-metadata

https://www.mathworks.com/matlabcentral/answers/349701-overwrite-an-image-with-new-imfinfo-data

[Walter Roberson]

tl;dr : Comment is the only metadata that Matlab itself supports writing.

[Michael Phillips]

Thanks Stephen! This is the link that really helped:

https://www.mathworks.com/matlabcentral/fileexchange/42000-run_exiftool

If you're running MATLAB on a Mac though you have to change

test = which('exiftool.exe');

to

test = '/usr/local/bin/exiftool'

or whatever path is appropriate for where you've downloaded the exiftool.

Thanks again!