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Bad year for biometrics

Not a good year for biometrics, especially for face recognition:

From RISKS Digest Vol. 24:

“Apparently the BKA (German equivalent of the FBI) tested face recognition,
spent 200K euros to test the system in a rail terminal in the city of Mainz
and basically declared it worthless in terms of being an investigative tool.
Apparently (per the article) this is the first public trial under normal,
every day conditions (rather than having the conditions manipulated for a
good showing) and only matched 30%. Even when the lighting was modified to
be ideal, it only reached 60%. The BKA considers the system only useful if
the success rate is very near 100%.”

Oops…. But wait, it gets better: new german passports have to include biometric data for face recognition now.

Here’s what Fefe reports:

“One of the core features of the new passport is a frontal picture, as opposed to the slightly sideways one used before. The frontal pictures can be read and interpreted by a piece of software in the government office to calculate biometric data about your face, so all the fancy Frauenhofer-Anti-Terror cameras at airports, train stations, in taxis, hotels and the cabins in the city sex shop may be able to identify you.

For this to work, photographers were told how to take an exact frontal picture of you. They usually charge more for the biometrics ready picture than for a regular one too. So I went to a photographer’s shop and got my biometrics ready pictures taken. Before the picture is scanned into the computer at the government office, a transparent sticker with an outline and some orientation points is placed on top of the photograph to tell the software where to look for the face.

The software at the government office kept complaining that my picture was not showing a head in frontal perspective, although it was painfully obvious that it was. The surprisingly helpful lady re-placed and re-adjusted the transparent sticker several times to make the software understand that in fact, this is a frontal picture of someone who just happens to have a real egg head – but to no avail. Finally, she sent me on my way again to another photographer’s shop around the corner that supposedly produced acceptable pictures for the software with a 100% success rate. So I went getting new pictures taken.

The photographer at the second shop was a young and obviously street-smart German citizen of Turkish descends. After the second round of pictures was taken, he loaded them into Photoshop and copied one into a template file he had at hand. The template file was composed of rulers and grid lines for Photoshop, which seemed to mirror the requirements of our governmental biometrics software at the passport office. Once it again became obvious that my egg-head would not fit into the boundaries, he scaled it on the X-Axis to make it fit. Kiss your aspect ratio goodbye.

Now, I don’t understand much of the biometrics matching algorithms used by our government’s software. But the little that I do know about face recognition involves head geometry information, including the distance between eyes in relation to other distances, like the one between your nose base and mouth. Well, if you scale an image without preserving the aspect ratio, this information is changed.

What came out was a head shot that was happily accepted by the passport office software as a perfectly valid front shot and respectively is rendered into my passport as well as placed on the RFID chip digitally. The only issue is: that’s not me, or to be more precise, it is not my head geometry. May be I should be happy about this, since it will make life a bit harder for the government officials should my profession become entirely illegal in the future and cause them to search train stations and public places for me.”

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