exifreader

ExifReader

ExifReader is a JavaScript library that parses image files and extracts the Exif data. It can be used either in a browser or from Node.

ExifReader supports module formats AMD, CommonJS and globals and can therefore easily be used from Webpack, RequireJS, Browserify, Node etc. Since it is written using ES2015, you can also import the ES2015 module directly from your own ES2015 project.

Installation

Easiest is through npm or Bower:

npm install exifreader --save

bower install exifreader --save

If you want to clone the git repository instead:

git clone [e-mail]:mattiasw/ExifReader.git
cd ExifReader
npm install

After that, the transpiled, concatenated and minified ES5 file will be in the dist folder together with a sourcemap file.

Usage

const tags = ExifReader.load(fileBuffer);
const imageDate = tags['DateTimeOriginal'].description;
const unprocessedTagValue = tags['DateTimeOriginal'].value;

Support

The library makes use of the DataView API which is supported in Chrome 9+, Firefox 15+, Internet Explorer 10+, Edge, Safari 5.1+, Opera 12.1+. If you want to support a browser or Node.js that doesn't have DataView support, you should probably use a polyfill like jDataView.

Examples

A full HTML example page is located in the examples/html/ directory. The example uses the FileReader API which is supported by the latest versions of all the major browsers.

Also, there is a Node.js example in the examples/nodejs/ directory that uses jDataView to polyfill the DataView API.

Tips

• Only load part of the image file since the Exif info segment has a max size. I suggest 128 kB. See the examples folder for a way to do this.
• After parsing the tags, consider deleting the MakerNote tag if you know you will load a lot of files and storing the tags. It can be really large for some manufacturers. See the examples folder to see how you can do that.

Testing

Testing is done with Mocha and Chai. Run with:

npm test

Issues

• There is no support for IPTC XMP yet.
• The descriptions for UserComment, GPSProcessingMethod and GPSAreaInformation are missing for other encodings than ASCII.

Changelog

• December, 2016:
  • Merge IPTC branch.
  • Convert project to JavaScript (ECMAScript 2015) from CoffeeScript, transpiling to ES5 using Babel.
  • Remove need to instatiate the ExifReader object before use.
  • Add UMD support (CommonJS, AMD and global).
  • Publish as npm package.
• September 17, 2014:
  • Lower memory usage by unsetting the file data object after parsing.
  • Add deleteTag method to be able to delete tags that use a lot of memory, e.g. MakerNote.
• September 9, 2013:
  • Make parsing of APP markers more robust. Fixes problems with some pictures.
• July 13, 2013:
  • Throw Error instead of just strings.
• April 23, 2013:
  • Support hybrid JFIF-EXIF image files.
• April 22, 2013:
  • Registered with Bower.
• January 8, 2013:
  • Updated text about browser support.
• January 19, 2012:
  • Added text descriptions for the tags.
• January 1, 2012:
  • First release.