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I am trying to extract EXIF data from a image(jpeg) which has been dragged into the browser or has been selected via a html file input element.

I managed to preview the image within the browser using FileReader and FileReader.readAsDataURL as described here.

and I found a EXIF library which allows to extract the EXIF data of an image via javascript. But for me it only works if I use it with normal img tags which load their content over a URL.

I also found this question on StackOverflow where the accepted answer states that it is just not possible.

But I am pretty sure that it can be realized because 500px.com extracts the EXIF data immediately after a file is added for upload and before the upload has been finished.

Some ideas how it should be possible to extract the EXIF data from the base64 encoded image I get from the FileReader?

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4 Answers 4

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I finally found a client side solution for the problem:

  1. Read the file using the FileReader and the method .readAsBinaryString
  2. Then wrap that binary string into a BinaryFile object which is already included in the EXIF Library
  3. Finally call EXIF.readFromBinaryFile(binaryFileObject);

and its done :)

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5 Comments

Trying to include binaryajax.js in my project causes an access denied error, so this is not a solution for me.
The link to nihilogic.dk is dead.
Links to BinaryFile object and EXIF Library are also dead.
If you want to use exif-js, see my answer here: stackoverflow.com/questions/18981555/… – it does the trick pretty simple.
This code will work without creating an <img> tag: const fr = new FileReader(); fr.onload = () => { const result = exif.readFromBinaryFile(fr.result); }; fr.readAsArrayBuffer(file); "file" is an instance of "File" class
4

jQuery-fileExif javascript library reads image exif data before upload.
GitHub link, example jsfiddle from the library.

var someCallback = function(exifObject) {

    $('#cameraModel').val(exifObject.Model);
    $('#lat').val(exifObject.GPSLatitude);
    $('#lng').val(exifObject.GPSLongitude);
    // Uncomment the line below to examine the
    // EXIF object in console to read other values
    //console.log(exifObject);

  }

      try {
        $('#file').change(function() {
            $(this).fileExif(someCallback);
        });
      }
      catch (e) {
        alert(e);
      }

1 Comment

I get Access Denied in jquery simply trying to include the library in my project.
3

Have a look at the code of the FxIF firefox extension. It reads exif data using only JavaScript. To read the file contents, you can use the FileReader API of modern browsers.

1 Comment

I really want to avoid browser extensions. As i mentioned i am already using FileReady but I don't know how to extract the EXIF data from the data I get from FileReader
0

When you get your File class instance via the file input, do this:

import exif from 'exif-js';

const fr = new FileReader();

fr.onload = () => {
  const result = exif.readFromBinaryFile(fr.result);
  //    ^ EXIF data will be here
};

fr.readAsArrayBuffer(file);

Comments

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