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Currency Detection Discovered in More Products
netbsd_fan writes "BUGTRAQ is reporting that anti-counterfeiting spyware is being found in more and more products. What is also interesting is that these products block fair uses of currency images which do not break the law. What incentive do printer manufacturers have to treat their customers like criminals? Is this a precursor to DRM in scanners, CD drives, and output devices?"
Search on the usual suspect newsgroups and you'll find a "patch" that can easily be applied to Photoshop CS to turn the currency detection off.
It has been public information for a long time that there have been currency detection in digital color copiers. When I worked at Xerox this was publicly acknowledged (~4 years ago).
The currency detection was used to imprint a watermark into the reproduction image. That watermark identified the copier model and serial number that made the photocopy. The result was that the secret service could track down photocopied currency to the exact machine it came from. This supposedly worked for US bills, but I don't know if it recognized other foreign bills.
All thats changed now is that some devices stop printing the currency and instead print out some informational junk in its place. HP apparently does this in its Windows drivers, while Xerox did its watermarking in firmware on the actual device.
-molo
Using your sig line to advertise for friends is lame.
what happens when the note design changes?
As many people have pointed out, in every Slashdot FP on this topic, the detection algorithm works by finding a pattern of five small circles in a particular configuration (which looks vaguely like the Cingular logo, without the head-dot).
This same pattern occurs on US, Canadian, EU, and presumeably many other forms of world currency, so the same algorithm can detect all of them, without modification (and more usefully, without a huge library of bill designs that needs constant updating as various countries change the pictures on their money).
To make a new bill design fit the detection algorithm, the government needs only include that pattern of five circles somewhere in the design.
I included a link to a PDF of the pattern in a Slashdot post from a few days ago, if you want to see it.
With Photoshop we all heard about the workarounds. Though, I was wondering how effective the algorithm is in the first place. Does the quality of the bill come into question? I scanned a slightly used ten-dollar bill, and there was no trouble importing it into Photoshop CS. I saved the picture as a *.psd, and had no trouble reopening it. I applied several filters on the image with no problems. I have yet to try this on a 20-dollar bill. Either it only detects 20 dollar bills and higher, or the quality of the bill (i.e. slightly creased) dramatically affects whether the software detects currency.