If you've ever opened a ticket with image editing software commercial images (like Photoshop), you may have been an unpleasant surprise. Chances are that the software will be warned that it can not work with images of money. What do you make a composition? Or just resize or tweak something? No matter: as a precaution, they assume that you're going to counterfeit currency and prevent you from working with them.
In the case of Photoshop, introduced this detection algorithm currency in its CS version. Some printers and scanners also use a similar system and you'll find it almost impossible to scan a ticket or print one copy. How exactly this detection system? It is not easy to answer this question for all the secrecy surrounding it, although some studies give us some clue.
The CBCDG, the body that controls all
If ever appear to you that error, you may have noticed that it contains a URL to redirect you to learn more about: www.rulesforuse.org (in fact, if you search for any printer drivers by this chain text, you could easily tell if it includes protection or not). The website belongs to the Central Bank Counterfeit Deterrence Group (CBCDG), a body comprising 27 central banks and that the fight against "digital" counterfeiting is centralized.
They are responsible detection system (they call CDS) using programs such as Photoshop, Paint Shop Pro or Corel Draw, without which supposedly developers or the programs themselves know exactly how the algorithm works that provide them. In 2004, when Photoshop first adopted the system of detection, Adobe product manager was referring to the method as a "black box" whose contents unknown.
"As the market leader and good citizens, it seems that simply do the right thing," explained product manager said when asked about the reason for incorporating Adobe CS algorithm. Indeed: by law the developers are not required to implement control so (a clear example of this is GIMP which does not), but decided to accept the request (do not know the degree of "insistence") and incorporate the CBCDG. The same is true with other commercial image editing programs.
A foolproof system?
Obviously, none of those involved in the creation or maintenance of this detection algorithm want to give clues to potential counterfeiters who want to skip. From there to there is so little information. It is also a mystery why the algorithm jumps with some bills and not others. In Hyperallergic was tested and discovered how two tickets marked as "specimen" yes were detected (this and this), while with others, even with your own photo of a ticket, no.
Moreover, it is more than demonstrated that the system is very easy to jump. A simple search on Google yields several methods (such as using other programs previously or modify images before opening them). However, in the unlikely event that someone will go through your head using home computers for counterfeit banknotes, which it thinks several times: it is more likely that you end up pillaging by other identification systems the impression.