QR codes

10 Articles

Hackaday Links: October 3, 2012

October 3, 2012 by 15 Comments

Cheap ergonomic mouse

If your had keeps cramping while using the computer mouse why not grab a hunk of wood and a couple of buttons to make your own ergonomic input device?

C# GUI for Arduino testing

Here’s a Windows GUI for controlling Arduino. [Rohit] put it together using C#. It should make development very simple as you have control of almost everything before you need to worry about writing your own server-side software.

Networked strip lighting replaces the office overheads

[Jeremy] got tired of replacing the halogen bulbs in his office. He upgraded to ten meters of RGB LED strips. We can’t think they do as well at lighting up the room. But he did add network control so they can flash or change colors depending on what type of alert they’re signalling.

Woven QR codes

Now that [Andrew Kieran] proved you can weave a working QR code into textiles do you think we’ll see garments that have a QR code leading to care instructions? We could never figure out what all those strange icons stood for.

World’s largest QR code in a corn maze

The world’s largest QR code was cut out of this field of corn. It’s at the Kraay Family Farm in Alberta, Canada. Gizomodo called it “Stupidly Pointless”. But we figure if it got them a world record and put their website on the front page of Giz and Hackaday they’re doing okay. Plus, we whipped out our Android and it read the QR code quite easily.

QArt Codes, The Better Way To Put Picture In A QR Code

April 13, 2012 by 22 Comments

[Russ Cox], current Googler and formerly of Bell Labs, posted an awesome guide to putting images in a QR code. Unlike this terrible attempt I wrote last August, [Russ]’s method does much more than simply paste an image into a QR code and hope the error correction passes. This new method generates a unique URL to be encoded for each QR code. In other words, the embedded image is actually part of the QR code and not just a copy and paste attempt.

The basis of [Russ]’ hack is the ability to change the message contained in a QR code to be made of either ASCII/UTF-8 or decimal numbers coded as binary. By appending an anchor tag (i.e. http://swtch.com/pjw/#123456789...) to the URL that will be encoded, [Russ] can change a whole bunch of pixels in a QR code to make just about any image.

With a few tricks like building new Reed-Solomon encoded blocks, [Russ] can change where in the pixels required by the QR code are placed. This allows for the full-width image of PJW’s binary likeness to be displayed in the QR code.

[Russ] put up a QArt coder that allows anyone to put a pixelated image in any QR code. [Luke Shumaker] (thanks for sending this in, [Luke]) took this tool and put the ‘ol skull ‘n wrenches inside a QR code pointing to hackaday.com. Very nice work from [Russ], and puts my work to shame. I’ll go cry in a corner now.

Keeping Christmas Present Hunters Guessing With QR Code Gift Tags

December 22, 2011 by 31 Comments

qr-code-gift-tags

[Thadd Brooks] is a geeky dad of the highest degree. His kids are constantly trying to figure out what mom and dad bought them for Christmas, while he continues to think up ways to stymie their progress. He certainly could have put a few prank presents under the tree, but he opted to go a different route, confusing his smartphone-wielding kids with QR codes.

Each gift under the tree bears no name tag, rather they are adorned with a single QR code sticker which [Thadd] printed out. When scanned, the code brings his children to a page on his web server stating who the gift is for.

The catch? Well, the codes bring up a random page each time, attributing the gift to every member of the family along the way. There’s no chance that any of the kids will be able to correctly identify their gifts before Christmas Eve, when [Thadd] flips a switch on the server and reveals the actual gift recipients.

It’s certainly a clever, yet frustrating, way to keep his family on their toes, and we think it’s a pretty awesome idea.

If you’d like to see some of the pages he has created to confuse his kids, just click the “Search” button on the link above.