Face recognition software

November 2011

I have a good example of our old friend, the law of unintended consequences, moving into action again, and giving those of us who cherish our privacy cause for concern.  How comfortable would you feel if the camera that films you as you walk into a shop, or cross a public space, didn’t just take your picture, but worked out who you are? 

Computers don’t get cleverer; they just get faster, cheaper and take up less space.  It’s the software that grows in cleverness.  If you think of a car as a computer, and the driver as software, you’ll see what I mean.  Without a driver, the car is just a heap of metal and plastic, doing nothing.  Once you add a driver, it becomes useful, and all drivers are different.  Some are excellent, some dreadful.

So it is with software; as computers become able to handle more and more data faster and faster, so software designers are able to create programmes that can use that increased capacity to produce more and more inventive programmes.

A good example is face recognition software.  You may have already seen it if you use Picasa, the free (and very good) photo-organising software that Google give away.  Within that, you can set it to search all your photos for a particular person, once you’ve shown it a picture of that person.  It’s not infallible, but it is fairly useful, especially for large collections.

Facebook have something similar installed on their website (you can opt out if you want no part of it).

However, when it’s applied secretly it becomes worrying; in America recently they filmed a load of students walking around a University Campus, and simply by using some of the shelf software and matching the film to Facebook, were able to identify 30% of the students.

30% doesn’t sound too brilliant, but It would not be difficult for anyone with the money to build a huge database of mugshots just by trawling through perfectly legitimate public sources – Facebook, newspaper pictures, company websites and so on.  Once such a database exists you would apply the facial recognition software to the crowd you are trying to identify and see if any matches pop up.

The police will love it; once they have your photo, and access to such a database, they can analyse all the videos they have to see if you appear.  Newspapers and TV will love it, too – scanning a crowd to pick out infamous people and identifying their companions and the like.  Even shop owners might use it to identify and target their otherwise anonymous customers.  They will all know what just you’ve been up to.

 Or, at least, they’ll think they will.  The truth is, I just don’t believe it works reliably enough.  Voice recognition software has been around for ages, getting better and better, and it’s still pretty hopeless.  The same applies to handwriting recognition systems.  There really are not that many variations of two eyes, a nose and a mouth, and faces change anyway.  The danger is that we are all going to end up mis-filed, wrongly categorised and be accused of all sorts of stuff we didn’t do. 

This is quite apart from the considerable “privacy” issues that arise, a discussion for another day, perhaps, although the German authorities have already noticed this risk, and have told Facebook to stop using the system on German users.

Step forward the law of unintended consequences: software that was developed to help sort out photograph albums will be used to vilify or persecute some innocent chap just because he happens to look a bit like someone infamous.

I know this will happen because it always does; people with the same name as a public figure will all tell you that it causes a problem from time to time, and so it will if you have a similar face.  Lazy journalists, police or security guards will believe what the computer tells them, and act without checking.  The modern belief that “It’s on the computer, so it must be true” will come into play.

The fact is that merely being on a computer gives a statement no weight at all.  But try telling that to a government department, especially if they think they have your photo.