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How printers and Photoshop detect and refuse to process images of currency

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Re: How printers and Photoshop detect and refuse to process images of currency

#81

Post by Theodores »

diogenescynic wrote: post #25
pionar wrote: post #4

When I was in college (99-2000ish, maybe?), one of my roommates was an art major with a graphic design bent, and he had this high end printer and would copy and print $1 bills and take 20 at a time over to the vending machines around the corner from our apartments once a week or so. After about a month of doing this, the machines disappeared. Of course, he's the same roommate who later got arrested for wire fraud and…

>he had this high end printer and would copy and print $1 bills and take 20 at a time over to the vending machines I'm embarassed to admit that in middle school my friend and I did something similar as his dad ran a printing business out of his garage. It surprised us then that this worked so easily. Luckily we only used them on vending machines and we quit doing it before we got caught. It makes me wonder what more…

If you have the criminal connections you can buy forged currency in a similar way to how you can buy drugs, the idea being that you can make a return on your investment if you put the work in to shift 'the product'.

Quality is a factor in the price so (for example) a bag of 100 £1 coins might cost £60 but you might not be able to use them in vending machines due to the weight being wrong. Notes again have their price depending on quality and cut.

Re: How printers and Photoshop detect and refuse to process images of currency

#82

Post by grecy »

GigabyteCoin wrote: post #80
grecy wrote: post #72

Earlier quoted context omitted.

When I was in Ecuador (which uses the US dollar) it was extremely common to find fake $20s in your change. I could never spot them, but the locals could. They were exceptionally good, right down to the watermark, security strip, etc. etc. Even when I had a known real one and a known fake one, I couldn't tell them apart.

Well which part about the note made it a "known fake" to the locals?

They could feel the texture with their fingers (I couldn't tell any difference) and the security strip was a tiny, tiny bit longer than it should have been on the fakes.

Even after they told me what to look for, I couldn't tell.

Re: How printers and Photoshop detect and refuse to process images of currency

#83

Post by Theodores »

blah32497 wrote: post #77

Does anyone have any insight into why Adobe and printer companies actually care about this? Are they being paid to do it by the secret service? (and wouldn't that be public information?)

Digimarc wrote the software for the Central Bank Counterfeit Deterrence Group. News of this was reported in 2004:

http://news.cnet.com/2100-1012-5138816.html

Re: How printers and Photoshop detect and refuse to process images of currency

#84

Post by nate_meurer »

grecy wrote: post #82
GigabyteCoin wrote: post #80

Earlier quoted context omitted.

Well which part about the note made it a "known fake" to the locals?

They could feel the texture with their fingers (I couldn't tell any difference) and the security strip was a tiny, tiny bit longer than it should have been on the fakes. Even after they told me what to look for, I couldn't tell.

This is precisely the reason the U.S. Treasury still insists on using natural fiber in paper notes. There's more detail in this delightful Esquire article about the making of paper currency:

http://www.esquire.com/features/benjamin-hundred-dollar-bill....

Re: How printers and Photoshop detect and refuse to process images of currency

#85

Post by joering2 »

blah32497 wrote: post #77

Does anyone have any insight into why Adobe and printer companies actually care about this? Are they being paid to do it by the secret service? (and wouldn't that be public information?)

If you were living under the rock for last 6 months then I will answer you: no, it won't be public information, as most likely NSA/CIA/whomever surely would like you to print some notes, so they can catch you. So Adobe/others have a gag order/if any not to speak about the subject.

I would however think that they do that simply to protect themselves in case so that noone will come after them legally that they allowed counterfeit to happen (so easily). Sure you can always trick the machine/software, but hey at least Adobe did try to stop you so they do "work" in a good faith.

I once watched a documentary on counterfeits and it seems it would costs about $80 to produce a perfectly looking, no-difference $100 bill using the latest technology. Noone will ever attest its fake other than Federal Reserve, and thats only because they have never produced a note with this serial #. The real game, supposedly, is not in producing fake notes that pass all tests; the real "problem" is how you put enough number of bills in the circulation so that #1 you make plenty of money, and #2 you don't get noticed/caught.

Surprisingly, the price for a perfectly-fake bill is not going much higher than $80, and as the rumor goes, FedRe stopped producing $1,000 bills for this exact reason.

Re: How printers and Photoshop detect and refuse to process images of currency

#86

Post by Zhenya »

thirdsight wrote: post #22
pionar wrote: post #4

When I was in college (99-2000ish, maybe?), one of my roommates was an art major with a graphic design bent, and he had this high end printer and would copy and print $1 bills and take 20 at a time over to the vending machines around the corner from our apartments once a week or so. After about a month of doing this, the machines disappeared. Of course, he's the same roommate who later got arrested for wire fraud and…

Similar. A friend of mine used an epson stylus printer (new on the market then) and a scanner to copy £20 notes. They were inserted into the change machine in the local gambling arcade type place. It was stupid enough to accept a single sided copy. Out popped pound coins. He now works for GCHQ which is funny. Edit: just to add that these change machines were really naff and obviously built by the lowest bidder.

NAFF - At first I decided that it stood for 'Not Anything Fucking Fancy'

then I googled it and realized its british slang:'https://www.google.com/search?q=naff

Re: How printers and Photoshop detect and refuse to process images of currency

#87

Post by jjoonathan »

nappy-doo wrote: post #67
jjoonathan wrote: post #63

Earlier quoted context omitted.

You're right, that's the critical question. SVM on a picture of the note would be useless against all but the 12 year olds with paper and scissors. There's no reason to believe that the differentiating features from next years' printers would be separated by the same support vectors. I think the real security is still in features that require expensive equipment to duplicate. Is it really that hard to use cheapo phot…

And this is where you're wrong. Most detectors use a PIN diode or a phototransistor. Both work just fine with the SVM. Again, the security given in these detectors is SO good that even if I were to give you complete knowledge of the system, you can't beat them. I can't admit to having made counterfeits, but I can say that I've seen _all_ of them, and they do not work.

No, you haven't seen them all. That's a silly claim. And if the detector is what you say, I'm about 80% sure I know both why it worked so well and how to defeat it.

As much as I wish I could make a bet with you and test this, I wish for trouble from the secret service even less, so I guess that's off the table.

Re: How printers and Photoshop detect and refuse to process images of currency

#88

Post by cskau »

nate_meurer wrote: post #84
grecy wrote: post #82

Earlier quoted context omitted.

They could feel the texture with their fingers (I couldn't tell any difference) and the security strip was a tiny, tiny bit longer than it should have been on the fakes. Even after they told me what to look for, I couldn't tell.

This is precisely the reason the U.S. Treasury still insists on using natural fiber in paper notes. There's more detail in this delightful Esquire article about the making of paper currency: http://www.esquire.com/features/benjamin-hundred-dollar-bill... .

I can't seem to make your link work, but I managed to track down the original article so allow me to repost:

http://www.esquire.com/features/benjamin-hundred-dollar-bill...

Re: How printers and Photoshop detect and refuse to process images of currency

#89

Post by hatchoo »

pionar wrote: post #4

When I was in college (99-2000ish, maybe?), one of my roommates was an art major with a graphic design bent, and he had this high end printer and would copy and print $1 bills and take 20 at a time over to the vending machines around the corner from our apartments once a week or so. After about a month of doing this, the machines disappeared. Of course, he's the same roommate who later got arrested for wire fraud and…

When I was in the States, some buddies had some Philippine Peso coins which weigh and are roughly the same size as quarters. They used a few if these to operate coin-based laundry machines.

Re: How printers and Photoshop detect and refuse to process images of currency

#90

Post by wyager »

sliverstorm wrote: post #56
wyager wrote: post #7

This is one of the things that made me really see the value of free software. I did verify experimentally that the Eurion constellation alone doesn't trigger photoshop's image rejection algorithm. I think it would be fun to distribute a bunch of images that false-positive the digimarc algorithms, just to mess with people.

This is one of the things that made me really see the value of free software. How do you mean? Is there much (legal) value to be had from image software that can process accurate scans of currency? I'm just kind of confused here, what value you speak of.

Because my software should never tell me that I can't do something for non-technical reasons. Assuming I'm a criminal is wrong. If I was a criminal, breaking the law is my decision, and my software should not impede my ability to do so.
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