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Most laser printer printed pages have tracking watermark

brahmsyellowdots.blogspot.com

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Re: Most laser printer printed pages have tracking watermark

#51

Post by code_duck »

mrtron wrote: post #50
sliverstorm wrote: post #35

Earlier quoted context omitted.

Why on earth would anyone bother forging Canadian currency? Just ribbing on ya :p It is true, there are other preventative measures, but any one measure can be beaten. It's like computer security- any computer can be hacked, it's just a game of making it hard enough to hack that it is not worth it, or takes too long.

As a Canadian I can't stand your attempt at humour (sarcasm++). The Canadian mint actually produces a lot of coinage for other countries, is one of the most advanced in new techs, etc. They tend to sell out all of their collection coins, especially the large gold ones (including a 1kg coin). The game of making it hard enough/expensive enough to have it not worthwhile is the goal of every currency. The new 100$ bill d…

The humor attempt falls a bit flat especially given that Canadian currency has been hovering near parity with (or above) US currency for years.

Re: Most laser printer printed pages have tracking watermark

#52

Post by SteveArmstrong »

tripzilch wrote: post #25
Natsu wrote: post #5

Well-known, I'm afraid. You can find more information here: http://www.eff.org/issues/printers http://en.wikipedia.org/wiki/Printer_steganography It's probably related to the counter-measures against printing currency: https://freedom-to-tinker.com/blog/felten/photoshop-and-curr... There's some interesting information about what causes an image to be detected as currency here: https://www.cl.cam.ac.uk/~sjm217/project…

Well-known indeed (at least, I followed it with keen interest when it came out), but I think it's good that this resurfaces as I really don't think it got enough attention the first time around. Personally I think the most worrying bits of data are first the time stamp, and second the printer serial number. I say serial number is second because in a criminal investigation phorensics can also get a "fingerprint" of th…

The article postulates that there isn't a timestamp in the pattern of dots because the pattern is consistent on a specific printer, regardless of when the print happened.

Re: Most laser printer printed pages have tracking watermark

#53

Post by burgerbrain »

tripzilch wrote: post #25
Natsu wrote: post #5

Well-known, I'm afraid. You can find more information here: http://www.eff.org/issues/printers http://en.wikipedia.org/wiki/Printer_steganography It's probably related to the counter-measures against printing currency: https://freedom-to-tinker.com/blog/felten/photoshop-and-curr... There's some interesting information about what causes an image to be detected as currency here: https://www.cl.cam.ac.uk/~sjm217/project…

Well-known indeed (at least, I followed it with keen interest when it came out), but I think it's good that this resurfaces as I really don't think it got enough attention the first time around. Personally I think the most worrying bits of data are first the time stamp, and second the printer serial number. I say serial number is second because in a criminal investigation phorensics can also get a "fingerprint" of th…

"I say serial number is second because in a criminal investigation phorensics can also get a "fingerprint" of the printer by tracking imperfections in the way it's printed."

I know they used to be able to do that with typewriters, but can they do it with printers as well? I would suspect the imperfections of being too chaotic, or at least easy enough to change by changing the cartridge.

Re: Most laser printer printed pages have tracking watermark

#54

Post by anrope »

dsr_ wrote: post #3

Ahem. Most COLOR laser printers have tracking "watermarks". It's because the US Treasury frowns on printing your own replica currency, which would be unastonishingly easy to do with a color scanner and printer.

Not that it's a showstopper, but Photoshop has built in currency detection based on the EURion constellation, a pattern printed on a lot of currency worldwide to help prevent counterfeiting. Kind of cool.

http://en.wikipedia.org/wiki/EURion_constellation

Edit: Of course I learn after posting, apparently EURion is not what Photoshop looks for, but rather a digital watermark. The detection is given to Adobe as a binary from a security firm.

Re: Most laser printer printed pages have tracking watermark

#55

Post by tomkarlo »

kijin wrote: post #23
dsr_ wrote: post #3

Ahem. Most COLOR laser printers have tracking "watermarks". It's because the US Treasury frowns on printing your own replica currency, which would be unastonishingly easy to do with a color scanner and printer.

Isn't that why actual money has all those fancy strips and bumps? Canada just introduced $100 polymer notes this week. It's even partially transparent. Good luck faking that with consumer-grade laser printers. (Color inkjets might work better on transparent sheets.)

As long as there's older-style currency in circulation, a forger only has replicate those bills and not the new hotness... currency only tends to last a few years in active circulation (at most) but I'd assume that many people will still accept a bill from a style printed 10 or 20 years ago.

Re: Most laser printer printed pages have tracking watermark

#56

Post by tomkarlo »

ck2 wrote: post #47

The real crime here is there is no documented law these companies are following. They are obviously doing it under legal pressure - so where is the law on the books? This means it's a secret law that (at least the) American public is unable to inspect and attempt to abolish. Perhaps it's a secret part of the DMCA? What other laws do we not know about?

Why do you assume there has to be a law or legal pressure?

Lots of industries adopt practices like this to _avoid_ a situation where something will become a matter of law, because it has little or no impact on the sales of their products. If you're a color laser printer manufacturer, agreeing to do this is probably a lot better than maybe having the government regulate sales of your product or otherwise add red tape.

Re: Most laser printer printed pages have tracking watermark

#57

Post by sliverstorm »

code_duck wrote: post #51
mrtron wrote: post #50

Earlier quoted context omitted.

As a Canadian I can't stand your attempt at humour (sarcasm++). The Canadian mint actually produces a lot of coinage for other countries, is one of the most advanced in new techs, etc. They tend to sell out all of their collection coins, especially the large gold ones (including a 1kg coin). The game of making it hard enough/expensive enough to have it not worthwhile is the goal of every currency. The new 100$ bill d…

The humor attempt falls a bit flat especially given that Canadian currency has been hovering near parity with (or above) US currency for years.

Is that irony not part of the humor?

Re: Most laser printer printed pages have tracking watermark

#58

Post by hugh3 »

sliverstorm wrote: post #34
tripzilch wrote: post #25

Earlier quoted context omitted.

Well-known indeed (at least, I followed it with keen interest when it came out), but I think it's good that this resurfaces as I really don't think it got enough attention the first time around. Personally I think the most worrying bits of data are first the time stamp, and second the printer serial number. I say serial number is second because in a criminal investigation phorensics can also get a "fingerprint" of th…

Why is it a Bad Thing(tm)? Is this more tin-foil-hat stuff...?

I don't know. Apparently a lot of the people here are master criminals, because they seem to be awfully paranoid about the idea that police detectives can, if sufficiently motivated, deduce some information about their activities. (These sorts of folks must really hate Sherlock Holmes stories.)

Personally, as a law-abiding citizen, I'm really not too concerned about being the target of a police investigation, and if I ever am the target of a police investigation I'll be happy to hand over as much evidence as possible since it will assist the police in ascertaining the truth that I am not, in fact, the guilty party.

Re: Most laser printer printed pages have tracking watermark

#59

Post by hugh3 »

mindslight wrote: post #9
dsr_ wrote: post #3

Ahem. Most COLOR laser printers have tracking "watermarks". It's because the US Treasury frowns on printing your own replica currency, which would be unastonishingly easy to do with a color scanner and printer.

Actually, it's because consumer electronics manufacturers don't have the spines to stand up for their customers.

Or because as civic-minded folks they're happy to help the police to do what they can in order to catch criminals and protect the innocent?

Re: Most laser printer printed pages have tracking watermark

#60

Post by lisper »

hugh3 wrote: post #58
sliverstorm wrote: post #34

Earlier quoted context omitted.

Why is it a Bad Thing(tm)? Is this more tin-foil-hat stuff...?

I don't know. Apparently a lot of the people here are master criminals, because they seem to be awfully paranoid about the idea that police detectives can, if sufficiently motivated, deduce some information about their activities. (These sorts of folks must really hate Sherlock Holmes stories.) Personally, as a law-abiding citizen, I'm really not too concerned about being the target of a police investigation, and if…

You assume that the police care if you are guilty or not. They don't. The quality metric that police work towards is not finding the actual perpetrator, it is finding someone who can be convicted, or, even better, strongarmed into confessing and/or accepting a plea bargain. As a (mostly) law-abiding citizen myself I wish it were otherwise. But it isn't.

See e.g. http://www.youtube.com/watch?v=6wXkI4t7nuc

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