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Handhelds Hardware Technology

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.
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Camera Phones Read Hidden Messages in Print

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  • by plover ( 150551 ) * on Thursday February 15, 2007 @09:58PM (#18034172) Homepage Journal
    I hope their business plan calls for Fujitsu to give away decoders like Digital Convergence did with :CueCats.

    But serioiusly, did anyone ever use a :CueCat for its business-intended purpose? Even once would be remarkable. I have no idea why someone would waste time trying this with a cell-phone, unless they were already a geek -- and then they'd be busy trying to find ways to hack it, not to use it.

    • Re: (Score:3, Informative)

      by slash.dt ( 701002 )
      This is software and will work with any digital camera - though you would want to use a web-enabled device like your cellphone so that you can go to the link. So there is no need for dedicated hardware.
    • by robaal ( 1019298 )
      ...easy for camera phones to decode...
      • ...easy for camera phones to decode...
        Most low-end prepaid cell phones that I have seen in stores in my part of the United States do not include a digital camera. Therefore, Fujitsu would have to either 1. market this technology to advertisers trying to reach people with high-end phones, or 2. deploy more camera phones.
        • by robaal ( 1019298 )

          ...easy for camera phones to decode...

          Most low-end prepaid cell phones that I have seen in stores in my part of the United States do not include a digital camera. Therefore, Fujitsu would have to either 1. market this technology to advertisers trying to reach people with high-end phones, or 2. deploy more camera phones.

          Unless it's vastly different in the US, I'm pretty sure you'd get some camera-phone nearly-free with a contract. I believe separate, basic, camera-phones aren't prohibitively priced either.

          It's not like these are only high-end models - I think it's rarer for a mobile phone to come without a camera nowadays.

          • by tepples ( 727027 )

            Unless it's vastly different in the US, I'm pretty sure you'd get some camera-phone nearly-free with a contract.
            In the US, a lot of people don't have $720 for a 24-month contract, even if it is paid $30 at a time, especially if the carrier locks out a lot of the phone's features (such as the use of an affordable data cable and the use of freeware MIDlets).
            • Just got a new contract from Cingular, and I got a Motorola L6 for $50 with a $50 MIR (so, basically free), and it's got no lock on the features (that I've noticed).

              It's data port is mini-USB, so I can use any cable that fits the port as a data cable, like that mini-USB cable that comes with just about every digital camera anymore. (Or maybe not anymore, actually, what with cameras using SD cards and the like.)

              Anyway, with the Motorola software (which isn't technically free, but there are freeware/sharewar
        • by sisinka ( 916373 )
          Most, even low-end and prepaid, cell phones do have at least lame cameras in my part of Europe, even the post-communist, IMO. And, some U.S. expats I've met here care much less about their phones compared to Europeans. (Not talking about Asia or Japan - now here I'm just guessing.)
          • Re: (Score:2, Informative)

            by jamar0303 ( 896820 )
            In Japan almost every phone sold is a cameraphone (only a couple of mid-range phones are sold with a cameraless version, mainly on their CDMA carrier, KDDI) and a barcode system called QR code has been in place for a long time that does what this is supposed to do (except that it was a 2D "barcode").
        • This is made for Japan, where carriers will subsidize at least $400 of any phone's cost (that's why Japanese people pick up on phones quickly- they get all sorts of cool phones for free that US carriers are too cheap to subsidize) with a contract.
        • Re: (Score:3, Interesting)

          by Dogtanian ( 588974 )

          Most low-end prepaid cell phones that I have seen in stores in my part of the United States do not include a digital camera. Therefore, Fujitsu would have to either 1. market this technology to advertisers trying to reach people with high-end phones, or 2. deploy more camera phones.

          The United States mobile phone market is different to the European market is different to the Japanese market.

          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 successfu

        • by Thansal ( 999464 )
          At $60 you can get a prepaid cammera phone (snapper) from virgin mobile (you can probably get a deal if you buy it in a store)
          At $0 you can get a bluetooth, camera phone (MotoV551) from Cingular with a 2yr contract.

          Camera phones are cheap these days, I actualy didn't want one, but got oen any way as a free bluetooth phone was tempting (yay for easy data transfers). Admitedly bluetooth is such a cheap technology that they should just put it any any phone...
    • Am I the only person here that's concerned with them finding/celebrating new ways to add information to adverts in a way that is barely discernable by the human eye? It sounds 100% subversive to me, even assuming it is used "properly" to add "extra content" to adverts.
    • I tried to use my CueCat for it's intended purpose, but it didn't work. I tried many times to get the damn thing to work, but it never recognized what I was scanning. And I tried just about everything I owned.
      • Weren't the barcodes you were supposed to scan special codes found in advertisements? From what I recall it wasn't for the regular product codes. Ancient history, I could be wrong. I never used mine for it's intended purpose either.
        • Yep, they were special bar codes that were supposed to be in magazine articles to let you scan them and go to the web site for the article. I wanted one, buy my local Radio Shack was out of em.
    • by Misch ( 158807 )
      I remember an Intel webcam I purchased came with software for Windows t do basically this.

      The back page of the manual was printed in a strange yellow/orange pattern that the webcam could "read" and send you to a web page.
  • Scary Tech (Score:2, Insightful)

    by excelblue ( 739986 )
    Oh boy, another waste of technology, and why does this not seem original? If anything, it reminds me of the yellow dots some color laser printers would put on things. Surely, the same tech won't be used to prevent digital pictures, etc. at places will it?
    • Re:Scary Tech (Score:5, Informative)

      by spagetti_code ( 773137 ) on Thursday February 15, 2007 @10:19PM (#18034328)
      The unique [washingtonpost.com] identification [eff.org] of many (soon to me most or all) inkjets and color lasers was not
      done for you or me. It was done quietly for law enforcement [freedom-to-tinker.com] to be able
      to *find* the owner of any printed document.

      The enormity of that type of underhanded removal of privacy is
      just gobsmacking. And most vendors quietly went along with it.

      This technology will no doubt be used in a similar vein - any
      picture uploaded onto the internet can be traced back to *you*.

      Freedom takes another blow [la-articles.org.uk].
      • by Peyna ( 14792 )
        The unique identification of many (soon to me most or all) inkjets and color lasers was not done for you or me. It was done quietly for law enforcement to be able to *find* the owner of any printed document.

        Good thing I'm safe with my mono laser printer.
        • What you don't realise is that it quietly absorbs plasma from your body while you work and then prints a tiny amount onto the corner of every document you write.
      • O Rly? What if I paid cash for my inkjet printer?
        • O Rly? What if I paid cash for my inkjet printer?

          It'll still tie the printout to your printer when The Man executes a warrant to examine all your printers. So you'd better be damn sure you haven't done anything that'll lead investigators to suspect you, and haven't sent any correspondence to government departments - donning my tinfoil hat here, what is there to stop governments routinely examining correspondence for these markings and linking senders to particular printers?

          Has anyone reverse-engineered

          • This is why on all "important" documents you print the whole page with a yellow overlay. Or you just don't replace the yellow ink cartridge.
            • My cheapie Brother printer will not print unless all four ink cartridges contain ink. If you run out of even one color, you still can't print in black and white until you fill that color cartridge again.

              At first I thought this was just an artificial way to drum up sales of proprietary ink, but now I realize that it's much more sinister -- all documents must contain the Big Brother Yellow Dots! ^_^

      • To easly see the pattern of yellow in a print, go in a dark place with a bright blue LED flashlight. If you don't have any samples handy, just use some new US $20 bills. Have some color copies done at Kinkos and look for the tiny easly visable dots that show near black under blue light. In magazines, the pattern will have to be much larger to be captured by cheap low resolution cell phones with fixed focus.
      • Re: (Score:2, Funny)

        by mrogers ( 85392 )
        That's why I always write ransom notes by hand, using my own blood.
        • Re: (Score:2, Informative)

          by mopower70 ( 250015 )

          That's why I always write ransom notes by hand, using my own blood.
          Take my word for it: that's how you get caught. You need to write the note in HER blood.
    • by Hentai ( 165906 )
      Hrm. I'm surprised in this paranoid climate that noone has shut this down out of a panic that the turrists could use it to relay hidden communiques in strategically placed band posters.
  • Kill the barcode! (Score:3, Interesting)

    by Mr. Roadkill ( 731328 ) on Thursday February 15, 2007 @10:07PM (#18034240)
    Am I the only one who's annoyed by bar codes on CD covers and books?
    Of course, this probably wouldn't fare too well on a re-issue of the White Album...
    • Am I the only one who's annoyed by bar codes on CD covers and books?

      Of course, this probably wouldn't fare too well on a re-issue of the White Album...

      The idea is that this will not be visible to the naked eye - you should be cheering this announcment as a way to get rid of the barcodes that you hate but still keep the information.

      • by Mr. Roadkill ( 731328 ) on Thursday February 15, 2007 @11:29PM (#18034790)

        The idea is that this will not be visible to the naked eye - you should be cheering this announcment as a way to get rid of the barcodes that you hate but still keep the information.
        Um... I thought that was exactly what I was doing, while also pointing out a possible problem with certain kinds of image. Things might get interesting if you're embedding patterns of yellow in an image that consists of a uniform white, or - for that matter - any other uniform or near-uniform colour. I suspect that under some circumstances it WOULD introduce visible artifacts - it would need to shift the yellow balance in sufficiently large blocks for crappy cameraphones to be able to pick it up, so if you're adding that to a solid white or some other solid or near-solid colour it may be visible.

        (and who the hell modded me OT? Did they actually RTFA? And do they still have enough modpoints to come back and mod this "Flamebait"?)
        • I think the idea is that while the White Album may appear to be a uniform white to you, in reality it's not. It's mildly disturbing to think that a crappy cameraphone may have better colour vision than a human.
  • Consume. Breed. Sleep.
    • Re: (Score:2, Interesting)

      by troylanes ( 883822 )
      Don't forget OBEY
      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?
  • by mfh ( 56 )
    I bet this results in some interesting watermark lawsuits in the next little while.
  • truthiness (Score:5, Funny)

    by President_Camacho ( 1063384 ) on Thursday February 15, 2007 @10:18PM (#18034324) Homepage
    not entirely unlike those game pieces that need to be viewed through a colored filter

    I believe these days, the correct term is African-American filter.
    • by Anonymous Coward on Thursday February 15, 2007 @10:29PM (#18034380)

      not entirely unlike those game pieces that need to be viewed through a colored filter
      I believe these days, the correct term is African-American filter.
      Cut the politically correct bullshit. It's nigga filter.

      Filter stole my bike!
    • Troll? I thought it was hilarious!
    • Mod Parent Up (Score:5, Insightful)

      by Max Littlemore ( 1001285 ) on Thursday February 15, 2007 @10:36PM (#18034432)

      Who are these donkeys who mod fantastically bad puns down just because they contain references to terms which may be politically sensitive or incorrect? I mean come on, that pun was beautifully apalling. Moderating it as troll seems to lack an understanding of what trolling is.

      I have a good mind to suggest "Nigger Filter" just to desensitize idiots with mod points so next time they see posts like the parent, they won't get their jocks all knotty. Who needs karma anyway?

      • I thnk they took a hint and left you have a post rating of 2.

        BTW, I believe the technical term for the filter you proposed is called a Country Club.

        ZING!

        Political correctness is for people with serious personal issues. I never understood why PC people think it is politically correct to force their viewpoints on people who don't share their opinions. Tolerance means tolerating intolerance. Stereotypes don't happen for no reason.....
  • by StikyPad ( 445176 ) on Thursday February 15, 2007 @10:25PM (#18034360) Homepage
    I've already found the hidden message. Actually, once I learned of the technique, I was surprised at just how many of these hidden messages exist.

    ****SPOILER WARNING****

    01000010 01100101 00100000 01110011 01110101 01110010 01100101 00100000 01110100 01101111 00100000 01100100 01110010 01101001 01101110 01101011 00100000 01111001 01101111 01110101 01110010 00100000 01001111 01110110 01100001 01101100 01110100 01101001 01101110 01100101 00101110
    • maybe I don't like ovaltine. 01001001001000000110010001101111011011100010011101 110100001000000110110001101001 01101011011001010010000001001111011101100110000101 101100011101000110100101101110 01100101
    • by UnknownSoldier ( 67820 ) on Thursday February 15, 2007 @10:51PM (#18034546)

      #include <stdio.h>
       
      char m[] =
      "01000010 01100101 00100000 01110011 01110101 01110010 01100101 00100000 01110100 01101111 00100000 01100100 01110010 01101001 01101110 01101011 00100000 01111001 01101111 01110101 01110010 00100000 01001111 01110110 01100001 01101100 01110100 01101001 01101110 01100101 00101110";
       
      int main(int argc, char* argv[])
      {
          int v = 0;
          char *p = m;
          while( *p )
          {
              if (*p == ' ')
              {
                  printf( "%c", v );
                  v = 0;
              }
              else
              {
                  v <<= 1;
                  v += ((*p == '0') ? 0 : 1);
              }
              p++;
          }
       
          return 0;
      }
      --
      Unfortunately, Slashdot limits sigs to .120 characters. However, I was able to ingeniously circumvent this limitation by using a pseudo .sig !

      • v += ((*p == '0') ? 0 : 1);
        I believe it's more efficient to do the following (assuming '0' == 0x30 and '1' == 0x31):

        v |= (*p ^ 0x30);
        • Nice!
        • That is nice indeed. However, since it's cool to try to be portable, why not code it as

          v |= *p ^ '0';

          ? This way, you don't depend on the encoding value of zero being known, not even to a human reader of the code. Also, I seem to recall that C insists that the numbers are encoded in adjacent and increasing positions in the encoding (although I don't have time to dig up a reference on that right now), so this should be pretty safe. Personally, I would probably still code it using the + operator since I think

          • re: v |= *p ^ '0'

            This is not portable.

            While C requires that '1' == '0' + 1, it doesn't (necesarily) follow that '1' ^ '0' == 1.

            e.g.

            '0' == 63
            '1' == 64
            '0' ^ '1' == 127

            Tim.
      • Unfortunately, Slashdot limits sigs to .120 characters.

        You may want to check your math.
      • I've been learning Scheme for a few days so here's another version, in "functional-style" (as I understand it so far, ie. no side-effects):

        (define code
        (string->list "01000010 01")) ; Truncated. Results in '(#\0 #\1 ... #\space #\0 ...), Ugh.
        (define decode
        (lambda (lst)
        (list->string (map integer->char (map list->integer (split code))))))
        (decode code)

        But I also had to code the procedures list->integer, split, and word in 503 characters e
        • Another functional version, this time in Haskell:

          import Char

          bit '0' = 0
          bit '1' = 1
          binToChar w = chr $ foldl (\x y -> (2*x + bit y)) 0 w
          main = print $ map binToChar $ words code
          code = "01000010 01100101 00100000 01110011 01110101 01110010 01100101 00100000 " ++
          "01110100 01101111 00100000 01100100 01110010 01101001 01101110 01101011 " ++
          "00100000 01111001 01101111 01110101 01110010 00100000 01001111 01110110 " ++
          "01100001 0110
          • Cool, foldl cleaned mine up a bit. My thinking of it is muddled though.
            • > Cool, foldl cleaned mine up a bit. My thinking of it is muddled though.

              The expression "foldl (\x y -> (2*x + bit y)) 0 w" is essentially equivalent to the following procedural pseudocode:

              x = 0
              for y in w
              x = 2 * x + bit(y)
              end
              return x

              The foldl routine (along with the right-associative foldr) is extremely useful in transforming most kinds of "for [element] in [list]" control structures. Their actual Haskell definitions are (I believe, from memory):

              foldl f
      • Re: (Score:3, Insightful)

        by mennucc1 ( 568756 )

        echo 'ibase=2 01000010 01100101 00100000 01110011 01110101 01110010 01100101 00100000 01110100 01101111 00100000 01100100 01110010 01101001 01101110 01101011 00100000 01111001 01101111 01110101 01110010 00100000 01001111 01110110 01100001 01101100 01110100 01101001 01101110 01100101 00101110' | tr ' ' '\n' | bc -l | awk '{printf("%c",$1)}'
        Unix by any other name would not stink^H^H^H^Hsmell differently.
      • by StressGuy ( 472374 ) on Friday February 16, 2007 @08:42AM (#18037396)
        Hey!...y-you guys are just a bunch of GEEKS!....all this time....I...I've been hanging out with GEEKS!!!

        {...sniff...} and I thought I really was funny and insightful! {....sob!....}
      • v += ((*p == '0') ? 0 : 1);
        thats a long winded way of saying

        v += *p-'0';
      • import sys
        m = '01000010 01100101 00100000 01110011 01110101 01110010 01100101 00100000 01110100 01101111 00100000 01100100 01110010 01101001 01101110 01101011 00100000 01111001 01101111 01110101 01110010 00100000 01001111 01110110 01100001 01101100 01110100 01101001 01101110 01100101 00101110'.split(' ')

        for s in m:
        i = 0;
        for b in s:
        i = (i << 1) + int(b)
        sys.stdout.write("%s"% chr(i))
        print
    • T25seSBvbiBzbGFzaGRvdCBkb2VzIGEgYnVuY2ggb2YgYmluYX J5IHZhbHVlcyBnZXQgbW9kZGVkIGZ1bm55IG9yIGluZm9ybWF0 aXZlLg==
  • by alshithead ( 981606 ) * on Thursday February 15, 2007 @10:27PM (#18034370)
    I guess selling lemon juice for invisible ink has just been retired.
  • All that development money for a high tech version of Where's Waldo? O.K. So now for the obligatory... But I'm color blind you insensitive clods!
  • ...or maybe "Everyman's Barcode" since the majority of cell phones have cameras.

    This will be a boon for advertisers wanting to direct traffic to their web sites.

    Good...bad?

    I just think it is an advance tha makes it easier for consumers.

    Different? Yes. Good in a way, because now a cell phone can be deliberately used to picture a 'link' image (deliberately designated as such if desired), and users don't have to dink in the URL character by character.
  • by slash.dt ( 701002 ) on Thursday February 15, 2007 @10:47PM (#18034516)
    Mobile phones in Japan already have a function to read barcodes - rather than the traditional barcode that the west are used to, it is a small square of barcode information which holds a lot more data.

    You often see this barcode on advertisements next to the url - you can scan the barcode and save typing in the url. I've done it several times - even my non-techy wife uses the feature.

    This new announcement seems like a way that you can embed the information without having to have an obvious barcode spoiling the picture - but you will still need some tag to let you know that there was something there worth scanning.

    • Re: (Score:3, Informative)

      by Hal_Porter ( 817932 )
      It's called QR code

      http://en.wikipedia.org/wiki/QR_Code [wikipedia.org]

      The idea is that you print them on business cards, and people can scan your name and phone number into their phone quickly. Kind of useful in Japan where you end up with piles of business cards quite quickly.
    • by ^_^x ( 178540 )
      I was going to mention this, but you beat me to it...
      I don't think there's much reason to get excited about this here when we can't even do QRCodes on our phones... For years I've heard there are some that can do its Western counterpart, Semacode, but I've never seen a phone that can read them in person, and it's definitely not even 1/4 as widely adopted here -- I've really only seen them on parcels and machine parts for inventory tracking so far.

      So the hidden code/glyph is academically a bit interesting, b
  • Why not Semacode? (Score:3, Informative)

    by mungewell ( 149275 ) on Thursday February 15, 2007 @10:49PM (#18034534)
    The artical talks about the 'advantage' that you can link a picture to a digital domain.... so why not just use semacode or Q-codes. Then the reader knows your pushing a website/etc and will actually point their phone at it!

    Semacodes can store a lot more information and can be scalled to include more or less. They are FEC'ed and are quite relisiant to damage.
    http://www.semacode.com/ [semacode.com]

    You don't even need to use the offical Semacode decoder, there are Free projects around.
    Simon
    • That's pretty neat. Unfortunately QR codes are more or less the standard. Does anyone know of a QR Code reading MIDlet that will actually work on a variety of phones? I can't find one that works on a Moto RAZR V3i as this semacode application apparently does.
  • by Panaflex ( 13191 ) * <[moc.oohay] [ta] [ognidlaivivnoc]> on Thursday February 15, 2007 @10:51PM (#18034548)
    The CueCat [wikipedia.org] was a device to read barcodes out of printed materials into your machine - which then linked you up to the referenced website.

    Fortunately it was a commercial failure - as the "free" devices cost a huge amount of cash. I'm sure this will fare better, of course, because it utilizes customers existing equipment. But who knows what wonderful websites it'll forward you too, hmm?
  • by jd ( 1658 ) <imipak&yahoo,com> on Thursday February 15, 2007 @11:04PM (#18034616) Homepage Journal
    Why not use a 4-colour printer, where you have red, green, blue and then some non-primary colour that is monochromatic? A 0 is represented by the colour mix, a 1 by the monochromatic version. Just as easy to discern, as the monochromatic pixels will be picked up differently (giving you essentially the same shift as their technique) but would involve ZERO distortion of the image. "Hard to discern" is not the same as "no visible change".

    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: (Score:3, Insightful)

      by Stubtify ( 610318 )
      The benefit to the method described in the article (which is probably just modifying the yellow dot's angle and slightly shifting the image) is that it can be done on any 4 color press. You could modify the image accordingly, and when the printer prints it your done. Anyone printing the file would probably not need to even know there is a hidden pattern. This opens you up to using and 4 color (CMYK) printer in the world.

      Your idea however requires special ink, as well as extra heads on the press. For a magaz
      • Re: (Score:3, Insightful)

        by jd ( 1658 )
        Correction taken. CMYB (Cyan Magenta Yellow Black) is the standard for printing, yes. CMY is basically RGB rotated, so the printing press would then use a mix of the three primary colours for everything other than red, green or blue. The red, green and blue would need to be inks that were specifically designed to be very pure wavelengths, so they would not be your regular mixes by any stretch. The idea is that a composite red and a pure, monochromatic red should look like exactly the same red to the human e
    • Re: (Score:3, Informative)

      by NMerriam ( 15122 )

      So why didn't Fujitsu go with this method?

      You've basically reinvented Gray Component Replacement [wikipedia.org] (GCR) and Under Color Removal [wikipedia.org] (UCR), and they have nothing to do with hiding information. Replacing colors on the press in what is a theoretically neutral way is already done for many reasons.

      You're also depending on a perfect press, which doesn't exist (there are no bits or pixels on paper) -- you can't really swap ink mixtures in and out transparently. There is always a bit of difference due solely to the de

    • the human eye is guaranteed to register ABSOLUTELY ZERO change

      At least, the color-blind human eye. I think the saturated/desaturated pattern you (seem to) describe, if made big enough to be detectable by a crap phone camera, would be as much visible as the one described in the article.
  • What _is_ entirely unlike those game pieces that need to be viewed through a colored filter?
  • true story.. I developed a php script that embeds 3 bits of information on a 4x4 pixel array, using DCT and spread spectrum, but I did with the blue hue, which to my knowledge is the one humans see the worse ( because of the refraction on the crystalin, it actualy is out of focus on our eye, hence black lights from discos are blurry) hey fujitsu , hire me ! I could use a job near akihabara
    • oh yeah? well, I can embed 3 bits of information in a *3x1* pixel array! Or alternatively, *16 bits of information* in your 4x4 pixel array!

    • Know your anime? Look good in a maid costume?
      If yes, there's always work around akihabara!
  • I wonder if it's possible to get an otherwise invisible tattoo that reads, "By the way, that'll be $19.99/month. However, please limit your shots to those who consent in the future."
  • I'm sure the next use someone will come up with will be a mechanism for content protection. "Sorry, this picture is not authorized. Please remain calm and wait for the police."
  • A finnish company, upcode (www.upcode.fi) does this with a less hidden picture, in newspapers etc. You take a picture with your camera phone, the upcode software recognizes the code on the page and the code is sent to a server and a message (be it stock quotes or bus schedule info) is sent back.
  • Now if only they could reverse this process to store a picture in 12 bytes...
  • >
    >
    >
    >
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    >
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    >

    Hidden in the above whitespace is the phrase "I, for one, welcome our new invisible barcode overlords".
  • ...all the "Fnord!"'s. 12 bytes of UTF-16 in BMP = 6 chars. Perfect. I knew it...
  • Kodak did something similar with their professional papers. They embedded a recurrent pattern of dots in the blue channel (yellow dye) that could be seen on a scanner but was practically impossible to see with the naked eye. Hardware scanners then incorporated a 'tigger taggant' (It's been so long it could have been tiger taggants) detector and would lock out the user from printing the image unless a security override code was used. You couldn't defeat the mechanism by scanning it yourself, either, becau
  • Is this difficult to discerne in the same way that we were told lossy audio compression systems would be almost impossible to discerne from the original? That theory lasted about 5 mins, wonder how long this one will last?
  • Things like Shotcode and DataMatrix etc - see http://en.wikipedia.org/wiki/2D_barcode/ [wikipedia.org]. Then there's all the watermarking schemes...
  • They should use this technology on clothing, nothing like looking at some digipix where your friend's shirt says I'M GAY when you thought it was just an innocent plain white tee.
  • "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." ..as opposed to software written in colorblind languages.

There is no opinion so absurd that some philosopher will not express it. -- Marcus Tullius Cicero, "Ad familiares"

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