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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

#51

Post by jasonkester »

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…

In a similar vein, I remember a class trip on a Ferry from Seattle to Vancouver back in the 80s. There was a change machine that would give you four quarters for a dollar so that you could play video games.

It seemed smart, as it would give you the same four quarters if you used a Canadian Dollar or an American one. Or maybe not, as one kid found out when he stuck a $5 bill in and got 4 quarters.

Being 12, and therefore far more clever than the designers of this machine, the kids then proceeded to cut our a few thousand little rectangular strips of paper, roughly dollar sized, and clean that poor machine out.

And being 12, and having Ms PacMan machines as the only way of disposing of that giant sack of quarters, when it became apparent that there was no way to spend them fast enough, it naturally degenerated into a game of "Throw the quarter in the Ocean".

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

#52

Post by textminer »

nappy-doo wrote: post #39
minikites wrote: post #33

Earlier quoted context omitted.

What is SVM and PCA? That sounds interesting.

Replying here so you'll see it. PCA: Basically you represent your measurements as a covariance matrix about the data set you care about. You then find the eigenvalues and the eigenvectors of that matrix. These basically tell you the hyperplanes which most accurately represent your data sets. Unfortunately, I can't get into more details about how this is used for bill detection -- go read the patents and papers yourse…

I've adopted a similar attitude as you here when it comes to past machine learning jobs, and discussion of detail. What ends up being your bright shiny line that you don't cross? I tend to just not talk about the specific feature engineering, being relatively upfront about such basic things as "I used a random forest".

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

#53

Post by w1ntermute »

logfromblammo wrote: post #20
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.

They could add the detection to GIMP. But then that would reveal what the algorithm is. And that would allow specific strategies for producing false negatives or false positives. I'm still undecided about whether countermeasures to reverse engineering like this are useful or not in the long run.

Adding it to GIMP would be useless, because it would be trivial to produce a patch to disable the functionality.

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

#54

Post by nappy-doo »

dangrossman wrote: post #47
nappy-doo wrote: post #30

Earlier quoted context omitted.

Fun fact: The treasury department won't tell you what is actually on the bills. In fact, none of the governments will. You can analyze them till you're blue in the face, under whatever light or circumstances you want, but the treasury department won't tell you what security measures are on the bill, nor when they change them. Additionally, they sometimes change during print runs, and issues.

> the treasury department won't tell you what security measures are on the bill, nor when they change them Here are a few Treasury Department webpages telling you what security measures are on the bill, and they publish a press release with a new interactive site when they change them: http://www.newmoney.gov/newmoney/flash/interactive100/index.... http://www.newmoney.gov/uscurrency/redesigned100.htm http://www.money…

These are what they tell you about.

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

#55

Post by [deleted] »

nappy-doo wrote: post #54
dangrossman wrote: post #47

Earlier quoted context omitted.

> the treasury department won't tell you what security measures are on the bill, nor when they change them Here are a few Treasury Department webpages telling you what security measures are on the bill, and they publish a press release with a new interactive site when they change them: http://www.newmoney.gov/newmoney/flash/interactive100/index.... http://www.newmoney.gov/uscurrency/redesigned100.htm http://www.money…

These are what they tell you about.

[deleted]

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

#56

Post by sliverstorm »

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.

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

#57

Post by sliverstorm »

nappy-doo wrote: post #50
dsl wrote: post #45

Earlier quoted context omitted.

Fun fact: you are asking the wrong branch of the government. The Secret Service will happily tell you about security features of currency, and behind closed doors help you build methods to detect counterfeits if you have a reasonable justification. http://www.secretservice.gov/know_your_money.shtml

The secret service is under the treasury dept.

No kidding!? I did not know, nor expect that.

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

#58

Post by danso »

nappy-doo wrote: post #50
dsl wrote: post #45

Earlier quoted context omitted.

Fun fact: you are asking the wrong branch of the government. The Secret Service will happily tell you about security features of currency, and behind closed doors help you build methods to detect counterfeits if you have a reasonable justification. http://www.secretservice.gov/know_your_money.shtml

The secret service is under the treasury dept.

They used to be under the Treasury Dept. They are now under the Dept. of Homeland Security:

http://www.dhs.gov/department-components

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

#59

Post by MrBuddyCasino »

erichurkman wrote: post #37
diogenescynic wrote: post #25

Earlier quoted context omitted.

>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…

> It makes me wonder what more sophisticated criminals can get away with. A lot. http://en.wikipedia.org/wiki/Superdollar

That was a fascinating read, thanks!

Tl;dr: 100$ bills produced in all likelihood by a foreign government (suspects are North Korea, Syria, Iran) or maybe criminal gangs are so well done that they are practically indistinguishable from the original.

The numbers printed seem to be pretty low though, and not nearly enough to endanger the economy in any way. Probably its hard to launder the money?

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

#60

Post by [deleted] »

nappy-doo wrote: post #26
aaronem wrote: post #13

Earlier quoted context omitted.

Given that it was a decade and a half ago, and that even today's vending machine recognizers probably don't do much beyond making sure a few relatively gross features are present, I doubt the cost per counterfeit was all that close to $1.

You are absolutely, positively wrong on this front. The new bill detectors use PCA and SVM to analyze notes. They're so good the treasury department buys them because they're better than the best systems out there. Generally, however, the vending business is quite cheap. They buy the low end machine because there's not really a reason to bother buying the more expensive ones. However, go to a casino, or a foreign cou…

[deleted]
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