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3D Holograms Detect Fake Signatures
Roland Piquepaille writes "Several sources reported last week that a new technique that produces 3D holograms of handwriting could be used to detect fake signatures on checks, credit card receipts or other important handwritten documents. Here are pointers to Nature, Scientific American or BBC News Online. Instead of using 2D techniques to look at the sequence of pen strokes in a signature, this new method is based on 3D micro-profilometry which permits to translate the writing into an image showing dips and furrows of the sample so that anomalies can be detected. If you plan to imitate your spouse's signature, beware! Forensics have a new and very efficient tool. As an example, for the use of ballpoint pens on normal paper, the success rate was 100%. You'll find more details, references and pictures in this overview."
Abstract
For legal purposes there is a requirement for the validation of signatures and handwritten documents. A helpful method in this respect is the so-called superposed strokes analysis, based on the observation of some characteristics in the writing, such as some letters and their dynamics.
This paper introduces a promising new technique for superposed strokes analysis based on conoscopic holography. Through a non-contact 3D measure a 3D profile is created of the superposed strokes that allows the writing dynamics to be determined, such as, for example, if a stroke was drawn clockwise or counterclockwise.
We propose a 3D analysis by an opto-electronic system, in order to improve the graphology analysis for off-line signature verification.
I will bet my life savings that it cannot detect a fake signature with my signature. I sign my checks differently almost everytime and I dont have one set signature because I suck at writing script. Id like to see how it would fair then. I sometimes scribble my name, while other times ill write the letters out.
3D Holograms Detect Fake Signatures
Several sources reported last week that a new technique that produces 3D holograms of handwriting could be used to detect fake signatures on checks, credit card receipts or other important handwritten documents. Here are pointers to Nature , Scientific American or BBC News Online . Instead of using 2D techniques to look at the sequence of pen strokes in a signature, this new method is based on 3D micro-profilometry which permits to translate the writing into an image showing dips and furrows of the sample so that anomalies can be detected. If you plan to imitate your spouse's signature, beware! Forensics have a new and very efficient tool. As an example, for the use of ballpoint pens on normal paper, the success rate was 100%.
Nature describes the problem and its solution.
Let's turn to BBC News for more details.
Here is a an example of "profilometric acquisition by means of conoscopic holography. These strokes were made by a BIC pen on common paper. The investigation area is about 5 mm × 5 mm. (a) 3D view of the strokes' profile. It is possible to note the regularity in the (S) line. (b) 3D view of the strokes' profile. The presence of bumps is evident. (c) 3D view with a mirror along the z-axis."
The research work has been published by the Journal of Optics A: Pure and Applied Optics in its Septemebr issue under the name "Superposed strokes analysis by conoscopic holography as an aid for a handwriting expert." Here are two links to the abstract and the full paper (free registration needed, valid for 30 days, PDF format, 6 pages, 320 KB). The above images come from this paper.
How is this technique working? Surprisingly well, according to Nature.
If you want to see the
Nope, because you are after all you. You would not be forging anything. When you sign your name to something, you are defining the original signature, as in, it's yours.
And if you were to be picked out by this system as a fraudster, it would be relatively trivial for you to identify yourself, given some time. So there would be no risk of going to jail.
Would be 4d recognition. The 3 dimensions already listed in the article combined with time. Essentially, a device could record the 3 dimensions as you sign.
Liberty.
1. No one signs the same exact way twice. That's how some forgers get caught -- copying TOO exactly.
2. We have all developed habits. Although your signatures may look different from each other, the pressure patterns are usually identical. Forgery detectors use magnifying glasses to detect dicontinuities in the letters or words, indicating a lifting of the pen for a glance at the original being copied. Most people do not lift and replace the pen on the paper while signing their own name.
3. Some forgers use the trick of holding the signature being copied UPSIDE-DOWN so they can "draw it" instead of writing it. That way they avoid the traps of their own habits showing to an investigator. They are usually the good ones who escape being caught. This technique woiuld easily show that the signature was drawn upside down and last letter first, and they will be caught.
4. The harder the signature is to read, the EASIER it is to forge. My own signature is perfect Victorian calligraphy done with a chisel-point felt-tip or fountain pen. Let them copy THAT!
5. Most organizations never check signatures until there is a anamoly. By then, the pro forger is long gone.
6. Pro forgers will defeat these machines by practicing their marks' signatures until they are perfected.
As they always have.
My signature has always been inconsistent. Hell, letters start turning into odd scribbles when I'm in a hurry. I've seen my 'z' turn into an atrocious, indiscernible jumble of curves. It's close enough for someone at the bank to glance at and say it's fine, but if someone was actually going to look at it in detail they'll probably think it's forged.
You can get much more detailed information about how a pen is held, about the timing and order of strokes, and how much pressure is excerted with a modern computer tablet. Even if you have all that information, you don't get anywhere near "100% accuracy" for signature verification. Since the data they work with contains less information, we can pretty much conclude that it must be their experiments that are poorly done, not that they have hit on some amazing new technique.
That isn't to say that the technique is completely useless. But it won't solve the problem of document forgeries.
One question one needs to ask, however, is whether the authors have any connection to the maker of conoscopic holography equipment...
They're "AutoPen."