I can find your picture on Facebook, even though you were not tagged

A new facebook application, face.com, applies face recognition to pictures in Facebook. The application process the tags of your pictures and your friends’ pictures, and goes off and tries to find more pictures, even though they are not tagged. For example, the application found these untagged pictures of me:

Face.com is surprisingly accurate. I encountered just a handful of false positives (pictures which were auto-tagged as friends, even though they were not). I imagine that it uses the social network as a way to reenforce tagging. Let us imagine that X is a friend of Y, but not a friend of Z, and that a face classifier had classified someone appearing in the same picture with X as either Y or Z with even probabilities. Therefore, there is a higher probability of the classified person to be Y, as he is X’s friend.

However, there this technology raises a disturbing concern for privacy. Until now, people could have some control over their pictures in Facebook by untagging themselves. Now, they can’t. Also, the algorithm searches through pictures by people who are not necessarily your friends. For example, friends of your friends. This means that it is very easy for your friends to find pictures of you have no control over, and not even be aware of. This is just my imagination, though. It is m wild speculation, though, I do not really know.

It is time for Facebook to give you more control over pictures of you. As untagging is not enough anymore, Facebook should let users remove pictures in which you are tagged, even though you did not upload it yourself.