Slashdot Mirror
New Technique Could Trace Documents By Printer
An anonymous reader submits "From this article at Purdue News, 'Researchers at Purdue University have developed a method that will enable authorities to trace documents to specific printers, a technique law-enforcement agencies could use to investigate counterfeiting, forgeries and homeland security matters.' The neat thing is that they are exploiting the characteristics of the print process itself to identify the printer." <update> One of the folks e-mailed me to say that the HP LaserJet 9000dn was one of the big ones tested with.
"DOCUMENTS PRODUCED BY BUSINESS MACHINES
It goes without saying that the proliferating market of modern business technology
such as copiers, fax machines and printers reduces a systematic forensic approach.
However, a number of projects report progress in the following:
Classification of full colour copiers
Doherty (31) gives an overview on state-of-the-art classification of ink-jet printers
and inks. Interestingly, the findings indicate that the results of TLC analysis
"before" and "after" show significant differences because the ink-components are
modified by heat during the print process. For specialists in traditional typewriting
examination, the overview of Frensel (41) on typewriters produced in the former
East Germany is of interest when identifying products manufactured before and
after World War II. Gervais & Lindblom (43) present a case illustrating detection of
digital manipulation on a facsimile printout. Hammond (47) compares the collected
technical data of facsimile machines. The demonstration of secondary typewriting
and alterations by the use of grids is today easily carried out by using the
appropriate computer software, as shown by Hicks (55). If there are actually
different computer assisted typewriting data collections, the system DRUIDE,
developed by Holzapfel & Marx (58) is comprehensive and designed for routine
casework. The traditional typewriter - disappearing on the market - still has its
forensic impact. Few references go back to the roots of typewriting examination and
commercial production, e.g., in the former Eastern Block. Horton (60) compares the
identifiability of the flatbed scanner and its products by comparing the marks on
scanned images. Lauterbach (68) describes 30 fax machines and their characteristic
printouts for identification purposes. A survey by Tweedy (129) on state-of-the-art
colour Laser copier identification by bitmap coding includes an overview of
counterfeit protection by the characteristics and class of the major copying
machines on the market. Wagner (134) presents the "Australian Toner Library" and
the discriminating power of FTIR as compared to ATR. In a similar direction, but
looking more specifically at the dating and sourcing of the Transmitting Terminal
Identifier on a fax document, is a study by Westwood & Novotny (138). White et al
(139) show the benefits of Surface Enhanced Resonance RAMAN Scattering
Spectroscopy (SERRS) for an almost non-destructive spectroscopic examination of
inks. Winter (141) studied the evidential value of the dot pattern of colour ink-jet
and bubble-jet printers for individual identification."
http://www.interpol.int/Public/Forensic/IFSS/meet
sarchasm: The gulf between the author of sarcastic wit and the person who doesn't get it.
It's forensics. You can trace bullet to a specific gun using forensics. You can trace a typewritten page to a specific typewriter using forensics. This is just a way to do the same thing with printers.
Don't blame me, I didn't vote for either of them!
Ok, you are so full of shit you stink from here.
your printers are incapable of printing less than it's maximum dpi. and no laser or inkjet let alone a dye-sublimation printer is capable of microscopic printing.
nice of you to make up crap, but let's at least make it slightly believeable.
show me a proof before you start throwing about lies as truth. Espically when it goes against physics and mechanical capabilities.
I worked at Kinko's for years. At least their color photocopiers had traceable features for as long as I worked there. Of course we all know if you try to copy cash on a color copier, it'll spit out entire sheets of green that cannot be turned off by the user. A tech has to come reset it and by policy, law enforcement is notified. But if you look super super closely, there is a pattern (not random, but specific to a particular copier) of yellow that can be used to track a copy back to a machine (and in the case of Kinko's, a closed-circuit camera of the person running the copies.) All the Kinko's I worked at/visited had cameras pointed at the color copiers.
;)
Of course Beavis and Butthead have shown us that for $1/copy you can make a decent copy of coins...
There's an old slashdot story about something similar as well.
LOAD "SIG",8,1
LOADING...
READY.
RUN
He's not full of shit. High quality printers do this already, and many also don't allow the specific color of currency to be printed out perfectly right. The average person printing off a picture of their vacation won't notice the subtle change, but counterfeit money will just look... "off"