QR code (2D barcode) coding and decoding algorithms?

Question

Looking for free/opensource code or description of algorithms to code (simple) and decode (hard) the 2D barcode QR code.

It doesn't seem like a trivial problem, but it's so popular in Japan that there must be something already available...

Answer 1

I have a colleague who worked on ZXing ("Zebra Crossing").

That's got a fair variety of platform support.

Answer 2

Here's a good LGPL library for encoding QR code libqrencode

Libqrencode is a C library for encoding data in a QR Code symbol, a kind of 2D symbology that can be scanned by handy terminals such as a mobile phone with CCD. The capacity of QR Code is up to 7000 digits or 4000 characters, and is highly robust.

Here's a Google code project that decodes QR code - aimed at iPhone, but is LGPL and the source is available. Should be adaptable...

Answer 3

PyQrCodec is a Python library for encoding Qr codes to a PNG and decoding them from a variety of image formats.

Answer 4

(In response to those asking about QR codes in PHP)

The Google Charts QR chart type might work for you, if you don't expect a lot of traffic, or if you can cache the images. It's extremely easy to use- just put the text to encode in the URL.

Answer 5

http://www.aipsys.com/qrcode.htm

Answer 6

http://www.qrcodegen.com You can create your private QR Codes easily.

Answer 7

Non-free SDK (C++/PHP): http://qrserver.com/software/

Free API: qrserver.com/api/documentation/create-qr-code/

Free Generator: goQr.me

Answer 8

http://www.swetake.com/qr/qr1_en.html

Just thought I'd mention this one which is explaining HOW they work.

Answer 9

If you want to use a different QR generator try try free QRtag api at http://api.QRtag.net