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Create QR Code (a matrix barcode) in TWiki pages, useful for mobile applications


This plugin generates QR Code in TWiki pages. A QR Code is a specific matrix barcode (or two-dimensional code), readable by dedicated QR barcode readers and camera phones. The code consists of black modules arranged in a square pattern on a white background. The information encoded can be any text, such as phone numbers, URLs, gelocation, vCard, vCal and more.

Syntax Rules

%QRCODE{ "text" ... }%

Parameter Description Default
"text" Text to encode as 2D barcode. (required)
ecc="M" Error Correction Capability. Valid values "L", "M", "Q", "H". "M"
version="..." Symbol version of QR Code, or size of matrix. Valid values "1" ... "40", and "auto" for automatic versioning. See details below. "8"
size="..." Module size, e.g. pixel size of a block (bit) that makes up the matrix of the barcode. "4"
format="..." Format of HTML img tag of generated QR Code image. Supported variables: $urlpath - URL path of image, $width - image width, $height - image height. "<img src='$urlpath' width='$width' height='$height' border='0' alt='' />"

QR Code has error correction capability (ECC) to restore data if the code is dirty or damaged:

  • level "L" - about 7%
  • level "M" - about 15%
  • level "Q" - about 25%
  • level "H" - about 30%

The length of text (number of bytes) and the ECC determine the symbol version (e.g. matrix size) required to encode some text. A version="auto" selects the version automatically based on text length and ECC. See "Attention" note in the "Plugin Installation & Configuration" section below before using "auto".

Overview of symbol version for default ECC level "M":

Version Matrix size Max. bytes
1 21x21 14
2 25x25 26
3 29x29 42
4 33x33 62
5 37x37 84
6 41x41 106
7 45x45 122
8 49x49 152
9 53x53 180
10 57x57 213
Version Matrix size Max. bytes
11 61x61 251
12 65x65 287
13 69x69 331
14 73x73 362
15 77x77 412
16 81x81 450
17 85x85 504
18 89x89 560
19 93x93 624
20 97x97 666
Version Matrix size Max. bytes
21 101x101 711
22 105x105 779
23 109x109 857
24 113x113 911
25 117x117 997
26 121x121 1059
27 125x125 1125
28 129x129 1190
29 133x133 1264
30 137x137 1370
Version Matrix size Max. bytes
31 141x141 1452
32 145x145 1538
33 149x149 1628
34 153x153 1722
35 157x157 1809
36 161x161 1911
37 165x165 1989
38 169x169 2099
39 173x173 2213
40 177x177 2331

The size of the generated image depends on the symbol version and the module size. For example, version="2" and size="3" results in a 99x99 pixels image. Version 2 has matrix size 25x25. A module size 3 turns that into 3 times 25x25 pixels, or 75x75 pixels. There is some required whitespace, which results in a 99x99 pixels image size.

See also VarQRCODE documentation for TWikiVariables.


Small QR Code for URL http://twiki.org/

You type You get (if installed) Simulated example

Encode URL of current topic

The QR Code of the current topic can be placed in a TWiki skin so that the URL can easily be read by smart phones. We use symbol version 8, e.g. the URL cannot be longer than 152 characters.

You type You get (if installed) Simulated example

Pulldown menu with QR Code

You can add a QR Code pulldown to the TopMenuSkin so that smartphone users can easily bookmark any TWiki page. Add the following to your TopMenuSkinTopicMenu after the Edit pulldown bullets:

You type You get (if installed) Simulated example
   * [[%BASEWEB%.%BASETOPIC%][<img 
qrcode.gif" alt="" width="16" height="16" 
/> %ICON{menu-down}%]]
      * [[%SYSTEMWEB%.QRCodePlugin][%QRCODE{ 
version="auto" size="4" }%]]

Interactive example

You can encode any text with this interactive form. The matrix size is set automatically using version="auto".

You type You get (if installed) Simulated example
<form action="%SCRIPTURL{view}%/%WEB%/%TOPIC%#QrForm">
<input type="text" name="qrcode" value="%URLPARAM{ "qrcode" encode="entity" default="Enter text" }%" size="20" class="twikiInputField" /><br />s
<input type="submit" value="Generate QR Code" class="twikiSubmit" />

"%URLPARAM{ "qrcode" encode="quote" default="Enter text" }%"


Plugin Installation & Configuration

Note: You do not need to install anything on the browser to use this plugin. The following instructions are for the administrator who installs the plugin on the TWiki server.

  • For an automated installation, run the configure script and follow "Find More Extensions" in the in the Extensions section.

  • Or, follow these manual installation steps:
    • Download the ZIP file from the Plugins home (see below).
    • Unzip QRCodePlugin.zip in your twiki installation directory. Content:
      File: Description:
      data/TWiki/QRCodePlugin.txt Plugin topic
      data/TWiki/VarQRCODE.txt QRCODE variable documentation topic
      lib/TWiki/Plugins/QRCodePlugin.pm Plugin Perl module
      lib/TWiki/Plugins/QRCodePlugin/Core.pm Plugin core module
      pub/TWiki/QRCodePlugin/twiki-logo-80x40-t.gif Logo file
      pub/TWiki/QRCodePlugin/qrcode-example-*.png Example QR Code image files
    • Set the ownership of the extracted directories and files to the webserver user.
    • Install the dependencies.

  • Plugin configuration and testing:
    • Run the configure script and enable the plugin in the Plugins section.
    • Test if the installation was successful: See example above.

ALERT! Attention, CPAN:GD::Barcode::QRcode version 1.15 needs to be patched as follows before you can use version="auto":

--- /usr/lib/perl5/site_perl/5.8.0/GD/Barcode/QRcode.pm.save1   2004-04-23 23:35:34.000000000 -0700
+++ /usr/lib/perl5/site_perl/5.8.0/GD/Barcode/QRcode.pm   2011-02-11 22:37:13.000000000 -0800
@@ -37,7 +37,7 @@
     $oSelf->{text} = $sTxt;
     $oSelf->{Ecc} = $rhPrm->{Ecc} || ' ';
     $oSelf->{Ecc} =~ tr/LMHQ/M/c;    #Not /LMQH/ => M
-    $oSelf->{Version} = $rhPrm->{Version} || 1;
+    $oSelf->{Version} = $rhPrm->{Version} || 0;
     $oSelf->{ModuleSize} = $rhPrm->{ModuleSize} || 1;
     $oSelf->{ModuleSize} = int($oSelf->{ModuleSize});

Plugin Info

  • One line description, is shown in the TextFormattingRules topic:
    • Set SHORTDESCRIPTION = Create QR Code (a matrix barcode) in TWiki pages, useful for mobile applications

Plugin Author: TWiki:Main.PeterThoeny
Copyright: © 2011-2012 TWiki:Main.PeterThoeny, TWiki.org
© 2011-2012 TWiki:TWiki.TWikiContributor
License: GPL (GNU General Public License)
Plugin Version: 2012-11-14
Change History:  
2012-11-14: TWikibug:Item7020: Categorize TWiki Variable QRCODE -- TWiki:Main.PeterThoeny
2012-09-03: TWikibug:Item6837: Added missing example screenshot qrcode-example-4.png
2011-07-12: TWikibug:Item6725: Change global package variables from "use vars" to "our"
2011-02-15: TWikibug:Item6647: Added TopMenuSkin example; added qrcode.gif 16x16 pixels icon
2011-02-13: TWikibug:Item6647: Added format=..."; XHTML fix for HTML img tag
2011-02-12: TWikibug:Item6647: Lazy loading of core and CPAN modules for better performance when QRCODE is not used; adding interactive example
2011-02-11: TWikibug:Item6647: Added version="auto"
2011-02-09: TWikibug:Item6647: Initial version
TWiki Dependency: $TWiki::Plugins::VERSION 1.1
CPAN Dependencies: CPAN:GD, CPAN:GD::Barcode, CPAN:GD::Barcode::QRcode, CPAN:Digest::MD5
Other Dependencies: gd (see http://www.libgd.org/)
Perl Version: 5.005
TWiki:Plugins.Benchmark: GoodStyle nn%, FormattedSearch nn%, QRCodePlugin nn%
Plugin Home: http://TWiki.org/cgi-bin/view/Plugins/QRCodePlugin
Feedback: http://TWiki.org/cgi-bin/view/Plugins/QRCodePluginDev
Appraisal: http://TWiki.org/cgi-bin/view/Plugins/QRCodePluginAppraisal

Related Topics: VarQRCODE, TWikiPlugins, DeveloperDocumentationCategory, AdminDocumentationCategory, TWikiPreferences

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Topic revision: r2 - 05 Oct 2017 - TomCraneAdmin

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