Easily add QR encoded data to any post using a simple mark-up.

WP-QREncoder

Allows post authors to easily add qrencoded images to their posts. Uses: QRcode Perl CGI & PHP scripts ver. 0.50: http://www.swetake.

vkt005

Use Wa QRcode as shortcode in post content or widget area without editing your theme files
USAGE: Use [qrcode] 
OR 
[qrcode content=”Put your content for QR code” size=”80″ alt=”ALT_TEXT” class=”classname”]
shortcode in your post content to show the QR Code without editing your theme files
EXAMPLE: [qrcode] it will qr code of current page url 
OR 
[qrcode content=”Put your content for QR code” size=”80″ alt=”ALT_TEXT” class=”classname”]
size = Size is given for the size of QR Code it should be in Pixel
alt = tool tip on Generated QR code => Default Value “Scan the QR Code”
Classname = it will user defined class to Captcha for better css controll
Shadow = true
OR
Place below function in your theme file where you want to display QR code.
 ‘your custom content’,’size’=>75)) 
?> 
OR
By using QR code button in Editor

Wa Qrcode

Use Wa QRcode generate to put QR code to you post, page or content area or widget area without editing your theme files

WP-QREncoder vs Wa Qrcode