qr code

web qr code:
http://stackoverflow.com/questions/9154980/is-there-a-way-to-scan-a-upc-or-qr-code-from-a-mobile-website

Android微信扫描二维码登入实现 基于ZXing开源工程:
http://my.oschina.net/jeffzhao/blog/107658

http://zxing.org/w/decode.jspx