[Dan] has come up with a novel solution to the age old problem of keeping your grocery list up to date. He’s added a bar code scanner and a Raspberry Pi under a kitchen cabinet. He calls the system “Oscar”, though we don’t see any grouchiness in his trash can. When [Dan] runs out of a product, he simply throws it away. Just above his garbage and recycling bin is a low cost barcode scanner. [Dan] holds the item until the scanner reads, then sends it on it’s way to recycling or the landfill. The decoded bar code is processed by a Raspberry Pi also hiding under the cabinet. The Raspberry Pi sends the data to Trello.comusing the Trello api.
If a product isn’t recognized by Trello’s database, trello dispatches a text message to [Dan’s] phone. He can then add the product information via a web interface. We think the user interface is what’s great here. Once products are in the database, the only thing that has to be done day to day is pause for a moment before throwing a package away. [Dan] has all his code up on github, and has also created a reddit thread for Oscar.
Either through QR codes, RFID, or near field communication, there seems to be some desire to share tiny pieces of data in a more physical and accessible form. [Chris Harrison], [Robert Xiao], and [Scott E. Hudson] of the HCI Institute at Carnegie Mellon have come up with a fairly interesting solution of making data more physical. They call it Acoustic Barcodes, and it’s able to store over a billion unique IDs in a small strip of plastic.
By engraving a barcode pattern into a piece of wood, stone, glass, or plastic, the guys then attached a microphone to the barcode and ran their fingernails across their invention. A computer interprets the sounds of a finger scraping against the acoustic barcode and produces a series of 1s and 0s.
This binary code can be used to look up various items in a database, or perform actions on a computer. In the video after the break, you can see these acoustic barcodes attached to a whiteboard to provide real tactile control of a video projector.
You can check out a PDF of the Acoustic Barcode paper here.
Continue reading “Acoustic barcodes deliver data with a fingernail and microphone”
This bar code tattoo was sent into us by [Lifespan]. Before going under the needle, [Lifespan] didn’t care much for tattoos. After seeing this video he realized that a tattoo could have dynamic content through domain redirection.
[Lifespan] spent a lot of time going over the different styles of 2D bar codes. QR codes were deemed ugly because of the three large squares in the corners. An EZ Code, like the one in his YouTube inspiration, are a proprietary format that must be read with a ScanLife app. He eventually settled on a Data Matrix bar code because of its open format and ubiquity in business and industry. To make the tattoo dynamic, [Lifespan] made the tattoo point to 5id5.com. With a little bit of smart phone wizardry, that domain can be redirected to any URL in a moments notice.
Like all well-planned tattoos, he found himself a very good artist to do the piece. [Connor Moore] managed to ink some skin at 15 dpi, which was a little risky, but the results came out great. While it’s not scarification via a laser cutter, barring fading this tattoo is technologically future proof.
[Scott Harden] came across a few posts about QR code matrix barcodes coming through on the 40m baud radio band. A few operators had captured the signals and assembled them into the code block seen above but they weren’t able to get a clear enough shot for a smartphone to decode the image. [Scott] took on the challenge and decoded the mysterious message himself. He tried some graphic editing to separate and enhance the color channels in order to up the contrasts of the image. This helped, but still couldn’t be read automatically. In a move similar to those seen in Hackaday’s own barcode challenges he dropped the image into Inkscape so that he could manually clean it up. Once it was overlaid on a grid the job was pretty simple. the left side did require some more image manipulation and precision”squinting” to eliminate interference from the vertical banding, but he managed to get the message. We won’t spoil it here in case you want to take on the challenge yourself. Good luck!
Playing store just got really, really fun because you can now build your own LEGO barcode scanner. As you can see after the break, it works well and it’s fast like a real barcode scanner. Unfortunately it doesn’t scan real barcodes. Or at least not traditional ones. As we learned in the Barcode Challenge, standard barcodes are a set of white and black bars that make up the ones and zeros of the code. This system uses the same white and gray bar system but it seems that it’s only the number of bars that identify an item, not a code created by a particular combination of light and dark. The items above are all scannable because the scanner counts the 2, 3, 4, 5 or 6 white beams on the bottom of each package. Still, it’s incredibly clever and a great toy for the young hackers to build if they have a little help.
Continue reading “LEGO barcode scanner”
Whenever someone manages to expose vulnerabilities in everyday devices, we love to root for them. [Adrian] over at Irongeek has been inspired to exploit barcodes as a means to attack a POS database. Based on an idea from a Pauldotcom episode, he set out to make a rapid attack device, using an LED to spoof the signals that would be received by scanning a barcode. By exposing the POS to a set of generic database attacks, including XSS, SQL Injection, and other errors easily solved by input sanitation, he has created the first version of an automated system penetration device. In this case the hardware is simple, but the concept is impressive.
With the hardware explained and the source code provided, as well as a basic un-sanitized input cheat sheet, the would-be barcode hackers have a great place to start if they feel compelled to provide a revision two.
[Thanks Robert W.]
Hacking with Gum got their hands on one of the persistence of vision display fans that Cenzic was giving away at Blackhat this year. It’s not the biggest fan-based POV display we’ve seen but it’s still a fun device to tinker with. They hacked into the EEPROM on the device in order to change the message the fan displayed.
This is very similar to the other EEPROM reading/writing we’ve seen recently. Hacking with Gum read the data off of the EEPROM and then disassembled it to discover how the message data is stored on the chip. This was made easier by noting the messages displayed when the fan is running. The first byte of data shows the number of words in the message, then each chunk of word data is preceded by one byte that represents the number of letters in that work. Data length was calculated based on the number of pixels in each display character. Once he knew the data-storage scheme, it was just a matter of formatting his own messages in the same way and overwriting the chip.
This is a great write-up if you’re looking for a primer on reverse engineering an unknown hardware system. If you had fun trying out our barcode challenges perhaps deciphering EEPROM data from a simple device should be your next quest.