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IDs in Color Copies
from the thought-paper-was-safe-didn't-you dept.
Slashdot received a lot of submissions of this Privacy Forum article about ID numbers being "watermarked" (just like digital watermarks) into copies made by any color copy machine. Go ahead and read it; the rest of this story assumes that you've read the link.
This not a secret; I remember a case a few years ago where a Columbia University copier was being used to create counterfeit currency, and the imprinted copies were traced straight back to the machine used to create them (amazingly, Altavista turned up an article about this case). Basically, when color copiers first started getting good, the Treasury started leaning on manufacturers to make their products less useful for counterfeiting. AFAIK, there's no law in effect saying that manufacturers MUST include an anti-counterfeiting features in their devices; but on the other hand, there aren't very many equipment manufacturers, so they're easy to lean on.
So today, any copy you make with any color copier will include a unique serial number. Make sure you don't copy anything that someone might want to trace back to you on a color copier. Maybe this isn't that big a deal; color copiers aren't home appliances.
But now home scanners and inkjets make up a nice copying system for as little $200-300. The Treasury Department has a big program devoted to preventing digital copying, and it looks like one of their main concerns is consumer-grade equipment. The Bureau of Printing and Engraving is even soliciting proposals from vendors which have a system suitable for embedding these watermarks in all output produced by color inkjet printers.
Fighting counterfeiting is fine with me. Thus the systems which "recognize" currency and refuse to scan or print it don't seem like too much of an infringement. But embedding serial numbers in all printer output? Maybe I just have a cynical mind, but I can think of about a hundred reasons this is a bad idea.
Re:Scanners (Score:3)
What they're talking about is a watermark embedded using steganography -- placed into the noise of the image, much like copy protection of digital images can be done by Photoshop (and other programs) now.
No problem (Score:3)
Perhaps someday, someone other than ourselves will realize this.
Finkployd
Deja Vu All Over Again (Score:5)
/.
Canon copiers (Score:4)
Digital (Score:5)
Paper and print is a whole different story. I would be wary of buying anything that watermarked everything I printed. I use a (granddaddy) AppleWriter II laser printer, and am reluctant to upgrade to a new printer if I am aware of this sort of thing. My big concern is who can read these watermarks, and why would they ever want to. (Other than for legal reasons, but I can't see myself printing threats off my printer.)
I can see newer laser printers being able to do this sort of thing, but I cannot see why a printer company would risk the public relations disaster that would ensue after someone found it producing a watermark, and any possible corporate backlash from including such a "feature".
I really don't think that much about my privacy, I'd like to think I'm pretty good to get along with in that way, but I (personally -- someone will hopefully point out valid reasons, but I guess valid reasons depend on who can read the watermark ...) can't see any justifiable reason for said watermarks except for perhaps malicious purposes.
Leaning, Concern (Score:3)
From the article:
While there is currently no U.S. legislative requirement that manufacturers of copier technology include IDs on color copies, it is also the case that these manufacturers have the clear impression that if they do not include such IDs, legislation to require them would be immediately forthcoming.
Hmmm. OK. So cooperation is used to forestall regulation. What with the proliferation and strange application of various laws, I'm actually more comfortable with manufacturer cooperation than regulation.
From Michael:
But embedding serial numbers in all printer output? Maybe I just have a cynical mind, but I can think of about a hundred reasons this is a bad idea.
The only threat I'm able to think of at the moment is to anonymous free speech. So if someone prints a newsletter with ideas someone doesn't like, the newslettter is branded "subversive", and can be tracked back to the printer. But then what? Can they really be shut down? And how many such "subversisves" really are anonymous anyway?
Hang onto the ink jet... (Score:5)
Ink jets have come a long way in the last few years, and they've reached the stage where, with the right paper, they can print photographic-quality pictures.
What does this mean? Well, everyone who's planning on doing something nasty-and-traceable will do it on an older printer. Some stupid people won't, and they'll get caught, justifying in the minds of the Man and the public that such watermarking is worthwhile. But, like drug smuggling, the vast majority will slip by unnoticed.
Freedoms will be curtailed, money will be wasted, and it'll all be for nothing. Have a nice day.
Counterfit how-to (Score:3)
Just don't mess up my image (Score:4)
As for the privacy issue... wouldn't such a encoding method be proprietary to the manufacturer? So what happens if I first copy the color image on a Xerox machine, and then take the copy over to a different machine, and copy that. Assuming the quality was not lost, the hidden ID code would not be decipherable by any (one) decryption algorythm.
Mike Eckardt [geocities.com] meckardt@spam.yahoo.com
Re:Scanners (Score:3)
I wonder what sorts of transformations these technologys are impervious to.. Since they're looking for on the web for watermarked graphics, presumably colour reduction (gif) and/or jpeg compression artifacts don't disrupt things. Will a slight blur or rotation? Can you embed an extractable watermark on white noise?
Re:How do they link the printer to me? (Score:3)
The SN may not lead investigators to your printer, but if you're already a suspect and the good, er bad guys (it's so hard to remember which one the cops are these days) have your printer, they can prove that some insidious document was printed on your unit, then all they have to do is try to convince the nice folks on the jury that you were there when the document was printed.
Should we worry that someone has already come up with a universal printer make/model ID that appears on all color copies and that this little detail has remained a secret? How likely is it that ABC Copier Company would say "No" to a court order demanding the name, address, phone number of the customer on the warranty registration for a particular printer?
Serial Number WaterMark (Score:5)
Which no counterfeiter would do anyways.
So why bother at all? It will make printers more expensive, and the government thinks that they get a tool to assist them in enforcing the law, but doesn't really - other coroberative evidence will have to be collected to get near enough to the printer with the watermark to check, and then traditional forensic science techniques could be used.
Hmmm... (Score:3)
Consider: the serial numbers can only be traced back to the printer, not the printer's owner (at least, not without records). Also, consider that the serial number has to be stored someplace where it can be modified easily, so that the printers can still be mass-produced. This means that it's still theoretically possible to modify the serial number.
Hehehe... my guess is that they'll use letters in serial numbers too, to allow for a greater number of numbers. This means that, once we figure out how to hack these, it'll be possible to put little messages into the watermarks.
I can see it now... Big Brother tries to read the watermark, all they get is strings of swear words
Fun with Kinkos! (Score:5)
Re:Digital (Score:3)
Not that we'd ever use $50 coins (it'd suck to lose one, presumably, depending on inflation), and holographic equipment can probably be rented or stolen or bought for a *reasonable* price but I do not know if counterfeiting money would justify a hefty-costing hologram printer (I have *no* idea how much they cost), and electronic money has it's own problems. (such as a controlled economy by an invisible hand.)
Some day, we may have to resort to using genetic code to identify ourselves, and our purchasing power will probably depend on what some database tells us. :) I jest, but it's not too far a cry off from reality.
Removing Watermarks (Score:4)
A second alternative is based on the premise that such an image is necessarily going to be faint, to prevent it obscuring what you're printing. If this is to scale with your print-out, then simply print your image much fainter (making the watermark effectively invisible), before reprinting the image upside-down on the same page, with the paper also inverted. This'll put a second copy on the paper, making it normal-strength, but the watermarks will only overlap in places (one being 180' to the other), so rendering most of it invisible.
Finally, switch back to a daisy-wheel. I don't care =HOW= good a manufacturer is, they can't make a daisy-wheel print watermarks, come hell or high water. Besides, daisy-wheels are great for listing print-outs. That is, if you want to turn the recipient into a gibbering idiot. :)
True Story (Score:3)
So one of my co-workers attempted to copy a dollar bill off the photocopier. It really did start printing out all black sheets of paper so he clocked and went home. (He had used a supervisors ID to use the machine).
Bemused I watched as the next day (showing off to his friends) he brought in some bleached single dollar bills and managed to scan in a twenty dollar bill. He conned our graphics guru into performing the necessary touch-ups (removing the seethrough portions for instance) and divided the image into the front and back.
Next he removed the little metal strips from 10 5'ers (he later just passed them out for change and no one noticed the missing strips). Somehow he managed to drag the strips through the 10 bleached dollar bills in the appropo spots.
After printing off 10 of them he promptly went to the bank to attempt to get larger bills. Which he successfully did.
Unfortunately for his stupid ass the bank later performed full tests on them, and reported the counterfeits to the FBI and National treasury. (The latter who confiscated the bills to go into counterfeit research). The FBI actually managed to lift an ID from the bills, and tracked the machine to the office.
I noticed we had a new employee outside our normal hiring schedule one day, and promptly had my friends evacuate the area and dissavow all knowledge. To make a long story short, he's in the pen, and I have a new cubicle =).
How to beat one digital watermark and problems.. (Score:4)
This is just an example but Digimarc underlines two serious problems with watermarks:
a) No watermark is invisible. No matter what anyone tells you adding watermark is a lossy process. The harder the watermark is to remove the more visible it is.
b) Watermarks will always be removable. If you have physical access to the machine creating the watermark (scanner, printer, whatever) you'll be able to edit/disable the watermark. Unless you embed the watermark in the paper fiber or something (but then you're tracking the media, not the data) it'll probably be enough to cut off part of the image or something similar to disable the watermark.
jay
Re:Canon copiers (Score:5)
Canon color lasers (800, 1000, 2400, ect.) all have a board that recognizes things like money and postage stamps. If you try and copy any of these it will spit out all black copies, and will continue to do so until a Canon tech is called. (They usualy call the Secret Service)
Shifting to AC mode for obvious reasons,
Older Canon copiers (CLC 1, 100, 200, 300, 500, 550, and 700/800) all will recoginze older US currency (and presumably other currency overseas) and produce a black/green mask over the copy. They will not, afak recognize stamps.
Occasionally, they throw the mask on a specific green, combined with scroll patterns that trips the DSP's currency detector.
Contrary to popular myth, these errors do not lock the copiers up, but they do produce an error, that is logged in the same place that jams and such are. Most companies require their technicians to report these errors and to cover behinds, such errors are reported to the Secret Service.
The older copiers, though, have a hard time recognizing the newer currency designs and will copy them quite well (or so I understand)
Newer machines (CLC 900/950, 1000/2400, 1120/1150) though, will not throw a currency error at all! These are the ones with the "hidden" barcode that identifies each copier.
BTW, if you want to see the code, look closely at the white areas of a copy, you'll see fine, yellow dots. This is the encoded patern.
,,, (Score:3)
-Robustness decreases proportionally with the square of the information contained
-Watermarks can almost always be either distorted beyond recognition (if the information content is high) or removed (if the information content is lwo) using a simple sequence of transformations, ranging from smearing spectral power peaks to scaling the image
-It's almost always possible to determine that watermarks or steganography was used because the entropy of the bits affected is most probably higher than that of the surrounding message.
--
Flames? Think I'm a karma whore?
I work for Kinko's... (Score:4)
... and this is something we've known about for years. Most color copiers do embed a serial number and many--particularly canons--will shutdown if you try to copy currency.
While the owner of the copier may not be officially required to register with the manufacturer, most non-consumer grade equipment needs to be serviced at least once a month. For example, each color copy generates a small amount of excess toner which is scraped off into a waste toner bottle; Xerox decided not to make this a user serviceable part on the Docucolor 40's (which are in almost every Kinko's in the world).
Kinko's, however, is generally more interested in making money and avoiding lawsuits than invading anyone's privacy. Every Kinko's Co-Worker is trained in the copy guidelines generated by our pack or ravenous lawyers about what we can copy and how. For example, the kid in the article should of been told that we can copy his driver's license but only in black and white and only at 129 percent.
Anyhow, for your extra dose of paranoia today consider this: even most of the new black and white copiers (from the Docutech to the Xerox 265) actually digitize and and store the images rather than flashing them to an analog transfer belt. All these copiers are equiped with a modem.
Re:What about tracing it? (Score:5)
The things you mention can be used to make a positive identification of the printer...but they have to find it first. The serial numbers, however, can be looked up in a manufacturers database. For those that didn't read the article (I almost didn't but I'm glad I did) here's something interesting from it:
To read these IDs, the document in question is scanned and the "noise"
decoded via a secret and proprietary algorithm. In the case of
Xerox-manufactured equipment, only Xerox has the means to do this, and they
require a court order to do so (except for some specific government
agencies, for whom they no longer require court authorizations). I'm told
that the number of requests Xerox receives for this service is on the order
of a couple a week from within the U.S.
In other words, according to the author, Xerox routinely, sometimes WITHOUT REQUIRING A WARRANT, gives out information regarding ownership of copiers based on these ID numbers.
numb
Re:Copying Stamps (Re:Canon copiers) (Score:3)
Just use mirrors, lenses, and perhaps filters to change the aspect ratio. Do you really think typical DSP software is engineered to a high degree to prevent crafty circumvention?
Say, on a scanner, have it scan an image that is shown to the sensor as twice its size with a color filter for multiple passes. Then have a software script clean it up. The final scanned image will look better this way anyway...
Now, if you wish to print that stamp collection out on your compromised printer, you have a few options through hardware. A simple way to fool the software, like the green of money, is to shift the colors, say green to red, red to blue, and blue to green, and do this to the print head connections after your software conversion of the image. If its pattern based, say those grovy lines on certificates that is being detected, why not invert *everything* and put inverters on the printhead? Now, for that, you will need to filter your image so the dots shoot out at the right contrast.
Hey there's a black van outside, let me check to see who it is...
NO CARRIER
Hang onto the ink jet... (and the driver too) (Score:3)
Thus, it could be possible for this tracing technology to be retrofitted to an existing printer via a driver upgrade. (Oh you're having print problems? May we suggest the new driver...)
If the serial number were still tied to the printer it would require some bi-directional communication. But that already exists in most printers host based UI functions.
But then if you think about it, this type of computer based processing opens up all sorts of other serial number sources. How about Pentium III serial numbers, ethernet MAC addresses, etc? (And haven't we seen these things already happen before, but only with digital documents?)
Thankfully, if somebody would probably do a software hack if this really happened.
How's that for paranoia? =)
Re:Digital (Score:3)
So, pacific islanders should start massive projects to poison sea creatures with shells, to prevent the devaluation of a shell-based economy? And those people who use large carved stones for money, they should outlaw a hammer and chisel?
You know, it'd be easier to simply change the tokens we use. If paper is hard to copy, then use coins with a chip in them, or somehow printing into the paper of the bill. If that proves impractical, either use tokens of a real worth (ie, gold) or use digital tokens and drop the whole idea of physical cash.
But, don't outlaw basic tools, or cripple them, preventing us from creating many things, just because we might forge a token.
The only way to preserve the value of cash is to make the cash inherently valuable, or to pick a token that can't be copied. If the colors and design of the bills can change, why can't the basic type of money change?
Anti-Counterfeiting Technologies (the whole thing) (Score:5)
Second, consider this problem from the point of view of the imaging equipment manufacturers. They clearly do not want to have some ill-conceived legislation rammed down their throats, that mandates some expensive technology be put into every device built. Even worse would be if every nation they sold too had different regulation that needed to be complied with.
So, the manufacturers with foresight are cooperating with the government to try to come up with inexpensive solutions that make the government happy.
Now, keep in mind that anticounterfeiting is distinct from encoding distinct marks into documents. I'm going to talk about the former first, and will come back to the latter.
As the original article pointed out, there are already both anti-counterfeiting and source indentification features built into current color copiers. However, these solutions are not necessarily extendable to consumer imaging, because they take place in a closed architecture as opposed to an open one.
Consider the path that a counterfeit note would take in a consumer based imaging system. It would travel from a scanner, to some image processing software, to the printer. At any point along the way it could be stored, manipulated, or transmitted via the internet. Each step may or may not be carried out by the same individuals. Becasue of this, the most logical place to put counterfeit prevention is in the printing step. The reason for this is that if the protection in the scanning or processing step is broken by any individual, then a print-ready file could be distributed to many others. However, putting the prevention within the printer makes it both less accessable to crackers, and requires that each potential counterfeiter break the protection again.
Let us focus then on the problem of the printing of counterfeit currency. Three ways of helping to solve this problem quickly present themselves.
1: Add currency-detecting logic to printers.
2: Add features to currency that printers cannot reproduce.
3: Add printer-specific watermarking to printers.
The trend in ink-jet printers is to make them cheaper and cheaper. Given this trend, it is not feasible to add much computational power to the printer without increasing their cost. For this reason, attempting to do general-purpose detection within the printer is not feasible at this time. This does not preclude, however, doing some quick and dirty detection that is computationally very simple. (For example, is the document being printed approximately 6" by 2.5").
The design of US currency is unsophisticated, especially when compared to that of other nations. Personally, I appreciate the simplicity and history of our design, but from an anti-counterfeiting point of view it is a nightmare. The latest iteration of our currency was a stopgap effort to try to make it somewhat more difficult to be digitally copied, but most of the new features (except perhaps for the watermark) are not well understood by the public at large.
Some simple features that could be implemented, easily recognized by the public, and impossible to duplicate on a consumer printer could include:
1: Printing on a transparant substrate.
2: (1) with areas that require perfect front-to-back registration.
3: Printing with reflective (foil)inks.
But as long as we are creating a new currency, we could consider hybrid solutions. That is, embedding some special patterns in the currency that are trivial for a scanner/printer to recognize, yet do not occur in other document types. This could be some specific geometric pattern, or a specific use of colors.
So, finally, we come to embedding a watermark in all images printed by an consumer printer. First, be aware that some office printers already do this, mostly color laser printers. But beyond that fact, this is really a separate issue from anticounterfeiting. Printer manufacturers are not going to volunteer to do this unless they are compelled to do so by governments.
But if a manufacturer were forced to implement this, the most obvious place to do so would be in the driver. This is because (as mentioned earlier) the ink-jet printer itself has little computational resources. The driver has the full resources of the system CPU and is traditionally where the dithering takes place. As far as making the patterns unique, one could either query the printer for a serial number, or simply use the Pentium III serial number, or perhaps the MAC address from the LAN card.
One closing lesson here, if you were feeling cocky by saying "no problem, I'll hang onto my old printer", then make sure you never upgrade the driver, as that is where this would most likely be implemented.
Well, in closing, I would love to sign this with my account name. I can't however, so just call me...
Anonymous Coward
Too Easy (Score:3)
Software aimed at specifically recognising currency and stamps is foolish: it will only recognise certain kinds of currency and stamps; it won't reconise foreign stamps; and it won't recognise other paper instruments which we would rather not see forged (certificates, etc.)
Software aimed at making forgeries trackable is more thoughtful; but it has obvious privacy implications, and is potentially technically defeatable (as many readers have mentioned).
The fundamental solution is to make currency harder to forge. Australian currency notes, for example, are printed on a thin papery plastic instead of on paper; they have a piece of artwork partly printed on each side, so it is obvious if the artwork on the two sides is misaligned; and they have a transparent section, so it is obvious if it is printed on the wrong "paper". In a similar vein, the new US $20 note has a "color change" section that looks different when viewed from different angles.
Trying to fix the problem by limiting the technology in a thousand different scanners, printers and copiers is a bad approach: it's analogous to trying to cover for your lousy encryption by crippling everybody else's computer. The Right Thing is improve the technology in the money itself.
Just wondering (Score:3)
Re:Reasons this is a bad idea. (Score:3)
The Supreme Court has upheld privacy rights via the 4th Amendment: the idea is that there is a strong similarity between spying and search-and-seisure.
However, contrary to popular belief, the Constitution does not enumerate the rights of the people. It enumerates the powers of the Government to restrict those rights. Rights belong to the people by default. I think most people have lost this key distinction. (I don't mean you.)
This excellent article about the LAPD's extensive use of wiretapping [newtimesla.com] contains the following:
Re:Canon copiers (Score:3)
Do you have a reference for this?
Good story, but since this is a Hard Problem, I'm skeptical, and I'm really curious how they do it if it is true.
Re:Digital (Score:3)
Slams at the government aside, I disagree. The only thing that makes ANYTHING valuable is agreement. A critical mass of human beings agree that cash is valuable, and so among human beings, it is. Give a $20 to your dog, he isn't impressed.
Try to define 'value'. I am a real estate appraiser. How much is that property worth? How much money would a willing buyer agree to give and a willing seller agree to accept, each experiencing no undue influence, for the property? How does anybody determine this? By looking to see what other people have done with similar property, thats how. Do any of these people know anything, do they have some secret access to value knowledge? No. They simply agree, and they support that decision by referencing other agreements.
A lot of people talk about the fact that paper money is no longer backed by precious metal. But so what? What makes the metal valuable? Agreement. How is that value affected by scarcity or abundance? Agreement. What caused the stock market crash of 1929 and the depression? Agreement. If a large enough mass of people no longer agree that what you have is valuable, then you are shit out of luck. Your stocks are worthless. Your money is worthless. A large enough mass of people agree that your bank is unsafe, it is.
Its all agreement, its all very nebulous, and it could all come crashing down around us. All it would take is a little consensus.
Rant concluded, plug commencing:
Visit Sleepless in Seattle [meepzorp.com].
======
"Rex unto my cleeb, and thou shalt have everlasting blort." - Zorp 3:16
A nation HAS to safeguard its currency (Score:3)
The Secret Service *has* to be serious about this.
Someone also asked about why the US doesn't invalidate old bills. It's true. Most countries, when they introduce redesigned currency, set a date in the future when the old currency is no longer valid legal tender (except to collectors of course).
The U.S. would never do this because the world views the dollar as "safe" and face it, there are a lot of people in foreign countries with trunks of hundred dollar bills (the old kind) stored. If they get an inkling that their stash will become worthless or greatly devalued, they'll be converting it to something else in short order.
Yup, subversives and criminals are also important to the US economy. When they lose faith in the dollar, they'll sell dollars and buy currency from some other country leading to a weaker dollar.
The dollar is the currency of the world, and I'm not just saying that because I am a US citizen. I grew up in the UK and generally hate US-centric attitudes, but this one is the truth.