Camera Phones Read Hidden Messages in Print 126
pikine writes "As reported by BBC News, Fujitsu has developed a technology that encodes 12-bytes of information in a printed picture by skewing yellow hue, which is difficult to discern by human eye but fairly easy for camera phones to decode using software written in Java." The first target uses are promotional contests and competitions, not entirely unlike those game pieces that need to be viewed through a colored filter.
Kill the barcode! (Score:3, Interesting)
Of course, this probably wouldn't fare too well on a re-issue of the White Album...
Re:They Live (Score:2, Interesting)
Has anyone else noticed that the fight scene in They Live is nearly exactly the same choreography as in the Cripple Fight episode of South park?
A very amateurish method. (Score:5, Interesting)
This method can trivially be extended to any number of non-primary colours, with sufficient distance from each other. At worst, you get four (any two mixed, plus all three, versus the monochromatic version of each), giving you four times the information that can be stored as a straight 1 or 0.
Still not enough? Then add two more states (1:3 monochrome:mixed and 2:3, respectively). This gives you 4 possible states, ie: 2 bits per pixel, ie: eight times the information of this colour distortion method, and I'm not changing a damned single pixel's value in the process.
Fujitsu's method would be much harder to extend, as it's lossy, by deliberately introducing distortions. Eventually, if you add enough distortion to an image, you'll wreck the image. My alternative is lossless. There is no noise. I'm merely substituting one method of producing a value for another method of producing exactly the same value. There is no noise. You can extend the method as far as technology is capable of distinguishing the types of composition, and the human eye is guaranteed to register ABSOLUTELY ZERO change, because value-wise, there has been absolutely zero change. You can remove the information from the image and replace it with new information as often as you like, because there has been nothing lost at any stage.
Am I some sort of genius? No, I just read the Madame Tetrachromat article on Slashdot a few years back and realized that you could use the same technique to deliberately hide information in plain sight. I also read articles explaining the limitations of RGB and why monitors cannot display all colours correctly to the human eye. By adding secondary colours in monochromatic form, you can produce a more "correct" image. By implication, the "right" colours would be hard for the eye to pick out but trivial for an RGB camera.
So why didn't Fujitsu go with this method? VHS versus Betamax. A six- or seven-colour printer might be superior in how much information it can encode. It might also be superior in the quality of colour printing it can do under normal conditions, perhaps by a significant margin in some cases. It would also be hard to sell to customers who already have perfectly good RGB printers and would be a lot more expensive. People use 6.1 megapixel digital cameras and then convert to highly-compressed JPEG format because they prefer to burn quality than burn money. This will be the same. People will accept the loss rather than pay more for a cleaner image. They always have.
(But I still think a true 7-colour printer would be damn amazing.)
Re:Low-end vs. high-end phones (Score:3, Interesting)
In the UK, camera phones are widely available for £50 inc. tax (US$90 approx) upwards, which is what most people would be spending on a phone anyway. (Sure, this isn't "low-end"- you can pick up a Nokia 1101 [wikipedia.org] and the like for £20- but most day-to-day mobile phone users will be buying in the £50-£100 range).
Anyhow, it strikes me that this technology would be most successful in Japan (different again); they've already got stuff like that which is popular there [slashdot.org].