Stripping EXIF data with Media Mover

After someone was discovered posting pictures to Flickr using an iPhone before it was officially released, it was fairly obvious to me that EXIF data could be used in ways that a user might not anticipate. Maybe I'm a bit behind the curve, but regardless, it struck me that it might be time to provide some tools that protect users from their cameras revealing who they are.

EXIF is a data standard that includes a variety of data in an image file. Generally these are things like exposure, model and make of camera (how the iPhone user got discovered), it can also include information about the user and copy right data.

In a case where compromising material is placed on a website, the details encoded into the photograph might be enough to connect back to the user- for example, authorities could use camera model and make to associate with a person who owns that camera. Worse, if the person has their name in the camera, it could be a dead give away.

Using media mover, and JHead, Robin and I planned out a way to strip out EXIF data from images. First we needed a good example for EXIF data
#wget http://www.exif.org/samples/ricoh-rdc5300.jpg
We can check the EXIF data in this file like so:
#identify -format %[EXIF:] richo-rdc5300.jpg
Now that we can see that we have EXIF data, we just need to remove it:
#jhead -dc -de ricoh-rdc5300.jpg
If we check the file again, no EXIF data:
#identify -format %[EXIF:
] richo-rdc5300.jpg

So all that really needed to be done was to wrap this code with a Media Mover module, and then we'd have a system that could strip out all EXIF data from user posts. Robin made short work of this task and stay tuned for the actual module release! Check out her work: MM EXIF

Add a new comment