Write image info using imwrite or other method

How to write imag info when writing an image. I can read the image info from one file using imfinfo but I can not find a way to wirte the info when writing the image, e.g., I have an image A and I want to write its info to an other image say B (as image properties/details).

Specifically, I want to write campera properties, e.g., exposure time, f-stop etc from one image to an other image

A_img_info=imfinfo('A.jpg');
A_img_info= A_img_info.DigitalCamera;
A_expTimes =A_img_info.ExposureTime;
%say B is an other image and write the A_expTimes to B
imwrite(B,'B.jpg') %how to write A_expTimes in the properties?

Answer 1

[Walter Roberson]

You cannot do that using imwrite().

Most of what you want to write is EXIF information. MATLAB does not support writing EXIF information.

See https://www.mathworks.com/matlabcentral/fileexchange/42000-run_exiftool for a File Exchange Contribution that invokes an external program to do the writing.

See also https://www.mathworks.com/matlabcentral/answers/349701-overwrite-an-image-with-new-imfinfo-data#answer_275016

Answer 2

[KSSV]

Read the documentation, thre are options mentioned to write into image.

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

[Abdulllah]

Can you kindly, update the last statement to include the exposure time when writing? I could not find it in the documentation. I am trying below statement however, it is thowring error.

imwrite(B,'B.jpg','jpg','ExposureTime','1.0')

[KSSV]

imwrite(B,'B.jpg','jpg','comment','ExposureTime = 1.0')

[Abdulllah]

Is it possible to include the all the information from imfinfo as a struct instead of separately adding each comment type. For example, In my above code I want to write all the information from image A to image B. I tried,

imwrite(B,'B.jpg','jpg','comment',A_img_info)

[Abdulllah]

imwrite(B,'B.jpg','jpg','comment','ExposureTime = 1.0')

The statement executed, however, it did not write the values in the properties/details.

[Walter Roberson]

You will not be able to use imwrite() to write properties such as Exposure Time. In JPEG files, those are recorded as EXIF information, which is structured binary data. For example, Exposure Time is EXIF binary tag 0x829A https://www.awaresystems.be/imaging/tiff/tifftags/privateifd/exif/exposuretime.html