July 30, 2021

Searching for Currency-Detection Software

Richard M. Smith observes that several products known to detect images of currency refer users to http://www.rulesforuse.org, a site that explains various countries’ laws about use of currency images. It seems a good bet that any software containing that URL has some kind of currency detection feature.

So you can look for currency-detecting software on your own computer. Just search the contents of your computer for the character string “http://www.rulesforuse.org”, and see if you find that string in any software such as an application or a printer driver.

Richard reports finding the string in drivers for the following printers: HP 130, HP 230, HP 7150, HP 7345, HP 7350, and HP 7550.

Go ahead, try it yourself. If you find anything, post a comment here with the details.


  1. Is there a quick command-line script I can run to do this? I’ve tried strings * | grep rulesforuse | more but this isn’t recursive.

  2. Fred Brehm says:

    Here’s a recursive command…

    find . -type f -exec fgrep -l ‘http://www.rulesforuse.org’ /dev/null “{}” ;

    Using xargs instead of -exec will work faster if you don’t have spaces in your file or directory names.

    In my /Applications folder of my Mac OS X 10.3 there don’t seem to be any references. I get some “Permission denied” message (I should have remembered to use sudo), but they are on things like Virex.

    The /Library folder (still searching but I’m impatient) is much the same. Some “Permission denied” messages on files unlikely to be involved with currency detection.

    BTW, I don’t have PhotoShop installed.

  3. The only files I found it in were the cache file containing this page and a plist for ecto where I was making to it.

    I don’t have photoshop installed either.

  4. Steve DaB says:

    searched the whole of my comp and nothing (i don’t have photoshop either)

  5. grep’s has a built-in directory recursion feature – just use -r and give it a directory:

    grep -lri rulesforuse /Applications /Library /System

    This turns up no hits on an OS X 10.3 system with apps like Corel Graphics, Graphic Converter, a full suite of print drivers, etc. but not Photshop.

    (As an aside spaces in directory names are no problem for xargs – if you use the -print0 argument to find so it’ll terminate strings with nulls and -0 with xargs so it’ll look for nulls instead of spaces)

  6. I do not have it either but I neither have Photoshop installed nor any printers.

    This is scary stuff. As industry bows more easily to the wishes of the government it demonstrates just how much influence the government has over industry and how quickly we are moving in the direction of socialism.

  7. Anonymous says:

    I don’t have Photoshop installed on my machine, but I do have Photoshop Elements and Gimp. And both of these programs were able to open the example photo given in the last article (the house with the 20 in the corner).

    Are there any features found in Photoshop that aren’t found in these two other extremely powerful photo editing packages?

    If there aren’t, then not being able to scan an image into Photoshop is pointless, if the counterfeiter can just by the cheaper Photoshop Elements (made by the same company) or just use the FREE Gimp software.

    These anti-currency restrictions, while scary on one hand, are humorous on another since, just like many other examples given right here on this site (broadcast flags, cd copy protections, etc.) they just don’t work. When will people learn this?

    On a related note, I just ran:

    sudo grep -lri rulesforuse /Applications /Library /System

    and it turned up nothing, but running:

    find . -type f -exec fgrep -l ‘http://www.rulesforuse.org’ /dev/null “{}” ;

    at least came up with the cache files.

    Could anyone please explain to me why one worked but the other one didn’t?


  8. The trouble is that if any application uses a library that compresses resources (for example, by LZW), you won’t see the text strings it uses in its UI. What’s more, it’s possible that any relevant software is deliberately obfuscated, and one elementary obfuscation technique is to encrypt string tables.

  9. Also under Windows if the string is stored as Unicode then grep won’t find it. (16-bit characters under Unicode vs. 8-bit ASCII that grep is built around)

  10. Assuming your grep considers ASCII 0 to be a character, you should be able to match it in Unicode strings with a period (r.u.l.e.s.f.o.r.u.s.e.).

  11. Mr Nobody says:

    The HP Photosmart 7960 has this “feature.” it is located in the file: c:WINNTsystem32spooldriversw32x863hph7900.dat

  12. Arian Kulp says:

    I didn’t do the system-level check for the URL but I tried to load the house/20 image from the previous article into Jasc Paint Shop Pro 8. I get a popup window “Action Not Supported – This application does not support the unauthorized processing of banknote images” followed by a reference to http://www.rulesforuse.org. Interesting…

  13. John McLusky says:

    I have an HP 5550 printer, and one of the files (c:windowssystem32spooldriversw32x863hpf4a607.dat) does indeed contain the Rules for Use URL.

    I printed out the image in http://www.cl.cam.ac.uk/~mgk25/eurion.pdf – interestingly, although the UK banknote was left intact, the Deutschmark and Euro notes were truncated with a small ‘http://www.rulesforuse.org/’.

    The banknote/lighthouse image printed without problems.

  14. I’m running Mac OS X 10.3.2 with Adobe Photoshop CS installed. This command:

    sudo grep -lri rulesforuse /Applications /Library /System

    results in the following hit:

    /Applications/Adobe Photoshop CS/Adobe Photoshop CS.app/Contents/MacOSClassic/Adobe Photoshop CS

    Note that the “Adobe Photoshop CS.app” shows up in the Mac OS X gui as a single file, yet it’s a “package’. I find it interesting where the file with the string is located, i.e., under a MacOSClassic directory as Photoshop CS is a native OS X application.

    I am using an Epson Perfection 3200 scanner and when attempting to scan one of the new $20 bills, I get the following message from the Photoshop app:

    “This application does not support the unauthorized processing of banknote images.

    For more information, select the information button below for Internet-based information on restructions for copying and distributing banknote images or go to http://www.rulesforuse.org

    Scanning a one-dollar bill worked fine with no detection.

  15. Tom Edwards says:

    Dan Kilo wrote:

    “As industry bows more easily to the wishes of the government it demonstrates just how much influence the government has over industry and how quickly we are moving in the direction of socialism.”

    One quarrel: You chose the wrong word. We’re not moving in the direction of “socialism” (which would be a good thing), we’re moving in the direction of fascism.