6 ms·

EURion constellation

155 points by curtis 11y ago

Ezhik 11y ago
That's interesting stuff. I wonder how the algorithms work, they have to be pretty fast if they're running on the printer itself. Also, slightly unrelated, but this for some reason reminded me of a certain issue some copiers had a while back, where they would swap certain numbers/letters for some reason when copying. Don't really remember what the cause of that was, though.
- Squarex 11y ago
  You probably mean this: https://news.ycombinator.com/item?id=6156238 https://news.ycombinator.com/item?id=6156238.
- tajen 11y ago
  The reasonable reason was compression. Parts of the image which looked alike were saved in the same buffer, that meant especially numbers. Which is the right way to lose the trust from your customers.
  - aidenn0 11y ago
    I've run into this with cell-phones too. Someone was reading an alphanumeric value to me, and one letter reliably sounded like one number. It was really odd, but apparently some of the compression techniques for phones use speech models and it seems that the person on the other end had an accent that hit a poor spot in the model.
  - wiml 11y ago
    It is an interesting observation about compression loss though. The more sophisticated any compressor gets, the more its artifacts are going to look semantically plausible. With simple technology, at first, you might get grainy or blurry images, or poor frequency response in audio. Those are easy to perceive as artifacts of the medium. Then you get things like JPEG fringes and context-dependent color shifts, which are a bit harder to learn to see past, since they are interacting with the image in sophisticated ways. JBIG (from the article) detects and compresses repeated textural elements or multiply-used glyphs, but if it applies that behavior to something that is actually information-bearing, it'll produce convincingly misleading artifacts. There's a sequence in _A Fire upon the Deep_ where two people are conversing over a link with rapidly deteriorating bandwidth— their communicators are compressing more and more heavily to compensate, until at the end the character is "interacting" with a sophisticated Markov-like model of their interlocutor with only a few bits per second of actual entropy from the far end. Or possibly none at all.
- zero_iq 11y ago
  I'd be very interested to know, as it seems to have some interesting properties: can run on limited CPU devices yet easily cope with high resolution images, in a range of colours and contrasts, and and can detect the pattern at a range of sizes and orientations.
bri3d 11y ago
Interesting, previous HN thread about money anti-counterfeiting, including EURion: https://news.ycombinator.com/item?id=9314523 https://news.ycombinator.com/item?id=9314523
larsboehnke 11y ago
interesting, thanks
hackuser 11y ago
Does open source software include this code? Does anyone know of examples?
Legogris 11y ago
Privacy-minded people could print this on a t-shirt.
- wilg 11y ago
  I wonder if photographers could just include it as a watermark to their images as well to prevent copying or tampering? But how would they add the watermark? GIMP I guess...
  - ovi256 11y ago
    If refusing to process/print Eurion marked things was a legally required feature (which it currently isn't) in printers/image processing software, it could pose quite a conundrum for OSS, if the law also requires that the feature not be easily disabled by an end user. It's hard for me to imagine OSS software with this property. Yet the law could demand it, and society might find it reasonable.
- myrryr 11y ago
  I do have this printed on a t-shirt, it is my Christmas with my family t-shirt. it doesn't work well at all, but every now and then it produces some pretty amusing results. Early versions of photoshop would put a big black box over me in some of the photos. fun for the whole family.
- draugadrotten 11y ago
  For even more fun: Grafitti
- wiml 11y ago
  I've always wanted to incorporate it into a mural or graffiti. Or car paint. There's a Gibson novel, I think, where the protagonist at some point obtains t-shirts with a pattern which is recognized by the universal DRM-enforcement code in video camera chipsets, making them invisible to surveillance.
  - jaxb 11y ago
DanBC 11y ago
This website talks about software detection of currency (and it's well worth a read): http://www.cl.cam.ac.uk/~sjm217/projects/currency/ http://www.cl.cam.ac.uk/~sjm217/projects/currency/ And here's a thread about it: https://news.ycombinator.com/item?id=7006848 https://news.ycombinator.com/item?id=7006848 Here's a thread about a BBC article: https://news.ycombinator.com/item?id=9776985 https://news.ycombinator.com/item?id=9776985
hatsunearu 11y ago
Here's one more thing that is used to track counterfeit currency and other purposes: secret tracking dots on printers. https://www.youtube.com/watch?v=sit6zUQKpJc https://www.youtube.com/watch?v=sit6zUQKpJc https://www.eff.org/pages/list-printers-which-do-or-do-not-display-tracking-dots https://www.eff.org/pages/list-printers-which-do-or-do-not-d...
- gherkin0 11y ago
  Couldn't that be defeated by a preprocessing step that inserts yellow dots at every grid position on the printout? If the extra dots were aligned correctly, I don't see how someone could recover the encoded information. Someone could probably create a printer driver that does that automatically. It probably would need some calibration to work, though.
  - schoen 11y ago
    I was briefly trying to do that as part of our project about this but I didn't figure out the proper pixel size and offset, nor whether you can use a fixed offset relative to the edge of the page or whether the printer tries to defeat this by slightly randomizing the offsets. I hope someone will figure it out. There's an additional challenge that some more recent printers often use a different watermarking technique whose details have never been documented.
bpicolo 11y ago
I was actually always curious as to why Adobe would go out of their way to add bank note detection. Now I know they didn't, some outside entity did it for them! Cool.
tgsovlerkhgsel 11y ago
Desktop software and modern printers/scanners no longer use this, they use something based on watermarking. I suspect it may have something to do with the fine pattern of parallel lines, which you will find on almost every currency. I suspect this patent might have something to do with it, but the math is beyond my comprehension: http://www.google.com/patents/US7720249 http://www.google.com/patents/US7720249 This patent was referenced by the above patent and seems even more applicable: http://www.google.com/patents/US6449377 http://www.google.com/patents/US6449377 (references patents 5583614, 4723149, 5633952, 5640467, and 5424807 which may be good further reading). I also remember someone mentioning that they reverse engineered the currency detector code in Photoshop(?) and got something like "fourier mellin transform, followed by checking specific values in an array".

155 points by curtis 11y ago

Ezhik 11y ago

That's interesting stuff. I wonder how the algorithms work, they have to be pretty fast if they're running on the printer itself. Also, slightly unrelated, but this for some reason reminded me of a certain issue some copiers had a while back, where they would swap certain numbers/letters for some reason when copying. Don't really remember what the cause of that was, though.

Squarex 11y ago
You probably mean this: https://news.ycombinator.com/item?id=6156238 https://news.ycombinator.com/item?id=6156238.
tajen 11y ago
The reasonable reason was compression. Parts of the image which looked alike were saved in the same buffer, that meant especially numbers. Which is the right way to lose the trust from your customers.
- aidenn0 11y ago
  I've run into this with cell-phones too. Someone was reading an alphanumeric value to me, and one letter reliably sounded like one number. It was really odd, but apparently some of the compression techniques for phones use speech models and it seems that the person on the other end had an accent that hit a poor spot in the model.
- wiml 11y ago
  It is an interesting observation about compression loss though. The more sophisticated any compressor gets, the more its artifacts are going to look semantically plausible. With simple technology, at first, you might get grainy or blurry images, or poor frequency response in audio. Those are easy to perceive as artifacts of the medium. Then you get things like JPEG fringes and context-dependent color shifts, which are a bit harder to learn to see past, since they are interacting with the image in sophisticated ways. JBIG (from the article) detects and compresses repeated textural elements or multiply-used glyphs, but if it applies that behavior to something that is actually information-bearing, it'll produce convincingly misleading artifacts. There's a sequence in _A Fire upon the Deep_ where two people are conversing over a link with rapidly deteriorating bandwidth— their communicators are compressing more and more heavily to compensate, until at the end the character is "interacting" with a sophisticated Markov-like model of their interlocutor with only a few bits per second of actual entropy from the far end. Or possibly none at all.
zero_iq 11y ago
I'd be very interested to know, as it seems to have some interesting properties: can run on limited CPU devices yet easily cope with high resolution images, in a range of colours and contrasts, and and can detect the pattern at a range of sizes and orientations.

bri3d 11y ago

Interesting, previous HN thread about money anti-counterfeiting, including EURion: https://news.ycombinator.com/item?id=9314523 https://news.ycombinator.com/item?id=9314523

larsboehnke 11y ago

interesting, thanks

hackuser 11y ago

Does open source software include this code? Does anyone know of examples?

Legogris 11y ago

Privacy-minded people could print this on a t-shirt.

wilg 11y ago
I wonder if photographers could just include it as a watermark to their images as well to prevent copying or tampering? But how would they add the watermark? GIMP I guess...
- ovi256 11y ago
  If refusing to process/print Eurion marked things was a legally required feature (which it currently isn't) in printers/image processing software, it could pose quite a conundrum for OSS, if the law also requires that the feature not be easily disabled by an end user. It's hard for me to imagine OSS software with this property. Yet the law could demand it, and society might find it reasonable.
myrryr 11y ago
I do have this printed on a t-shirt, it is my Christmas with my family t-shirt. it doesn't work well at all, but every now and then it produces some pretty amusing results. Early versions of photoshop would put a big black box over me in some of the photos. fun for the whole family.
draugadrotten 11y ago
For even more fun: Grafitti
wiml 11y ago
I've always wanted to incorporate it into a mural or graffiti. Or car paint. There's a Gibson novel, I think, where the protagonist at some point obtains t-shirts with a pattern which is recognized by the universal DRM-enforcement code in video camera chipsets, making them invisible to surveillance.
- jaxb 11y ago

DanBC 11y ago

This website talks about software detection of currency (and it's well worth a read): http://www.cl.cam.ac.uk/~sjm217/projects/currency/ http://www.cl.cam.ac.uk/~sjm217/projects/currency/ And here's a thread about it: https://news.ycombinator.com/item?id=7006848 https://news.ycombinator.com/item?id=7006848 Here's a thread about a BBC article: https://news.ycombinator.com/item?id=9776985 https://news.ycombinator.com/item?id=9776985

hatsunearu 11y ago

Here's one more thing that is used to track counterfeit currency and other purposes: secret tracking dots on printers. https://www.youtube.com/watch?v=sit6zUQKpJc https://www.youtube.com/watch?v=sit6zUQKpJc https://www.eff.org/pages/list-printers-which-do-or-do-not-display-tracking-dots https://www.eff.org/pages/list-printers-which-do-or-do-not-d...

gherkin0 11y ago
Couldn't that be defeated by a preprocessing step that inserts yellow dots at every grid position on the printout? If the extra dots were aligned correctly, I don't see how someone could recover the encoded information. Someone could probably create a printer driver that does that automatically. It probably would need some calibration to work, though.
- schoen 11y ago
  I was briefly trying to do that as part of our project about this but I didn't figure out the proper pixel size and offset, nor whether you can use a fixed offset relative to the edge of the page or whether the printer tries to defeat this by slightly randomizing the offsets. I hope someone will figure it out. There's an additional challenge that some more recent printers often use a different watermarking technique whose details have never been documented.

bpicolo 11y ago

I was actually always curious as to why Adobe would go out of their way to add bank note detection. Now I know they didn't, some outside entity did it for them! Cool.

tgsovlerkhgsel 11y ago

Desktop software and modern printers/scanners no longer use this, they use something based on watermarking. I suspect it may have something to do with the fine pattern of parallel lines, which you will find on almost every currency. I suspect this patent might have something to do with it, but the math is beyond my comprehension: http://www.google.com/patents/US7720249 http://www.google.com/patents/US7720249 This patent was referenced by the above patent and seems even more applicable: http://www.google.com/patents/US6449377 http://www.google.com/patents/US6449377 (references patents 5583614, 4723149, 5633952, 5640467, and 5424807 which may be good further reading). I also remember someone mentioning that they reverse engineered the currency detector code in Photoshop(?) and got something like "fourier mellin transform, followed by checking specific values in an array".