ExifReader

ExifReader is a JavaScript library (written in CoffeeScript) that parses image files and extracts the Exif data.

Usage

var exif = new ExifReader();
exif.load(fileBuffer);
var imageDate = exif.getTagDescription('DateTimeOriginal');
var allTags = exif.getAllTags();

Installation

The easiest way is to use Bower:

bower install exifreader

Support

The library makes use of the DataView API which is supported in Chrome 9+, Firefox 15+ and Internet Explorer 10+. If you want to support a browser or Node.js that doesn't have DataView support, you should probably use a wrapper like jDataView by Christopher Chedeau.

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 example/node/ directory that uses a simple wrapper for 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 have a lot of ExifReader instances. It can be really large for some manufacturers. See the examples folder to see how you can do that.

Testing

Testing is done with jasmine-node. Use either the Cakefile or jasmine-node directly:

jasmine-node --coffee spec/

Issues

• The descriptions for UserComment, GPSProcessingMethod and GPSAreaInformation are missing for other encodings than ASCII.

Changelog

• 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.