rQRCode, Encode QRCodes¶ ↑

All users of rqrcode are highly recomended to upgrade to version 0.5.5 ore later!

Short changelog¶ ↑

0.10.1 (Feb 11, 2016)

Changed so that gem wont include images and tests.

0.10.0 (Feb 11, 2016)

Merged as_ansi by Andy Brody

0.9.0 (Jan 3, 2016)

Added support for auto selecting qrcode size up to level 40. (only worked up to level 10 before)
Added numeric support during auto selection of qrcode mode.

0.8.1 (Jan 3, 2016)

Remove active support specific present?.
Fix so that all tests are run.

0.8.0 (Dec 18, 2015)

Added numeric QR code support
Dropped Ruby v1.8 support

Overview¶ ↑

rQRCode is a library for encoding QR Codes in Ruby. It has a simple interface with all the standard qrcode options. It was adapted from the Javascript library by Kazuhiko Arase.

Let’s clear up some rQRCode stuff.

rQRCode is a ruby only library It requires no native libraries. Just Ruby!
It is an encoding library. You can’t decode QR codes with it.
The interface is simple and assumes you just want to encode a string into a QR code
QR code is trademarked by Denso Wave inc

Installing¶ ↑

You may get the latest stable version from Rubygems.

gem install rqrcode

Using rQRCode¶ ↑

require 'rqrcode'

qrcode = RQRCode::QRCode.new("http://github.com/")
image = qrcode.as_png
svg = qrcode.as_svg
html = qrcode.as_html
string = qrcode.as_ansi
string = qrcode.to_s

Image Rendering¶ ↑

SVG¶ ↑

The SVG renderer will produce a stand-alone SVG as a String

qrcode = RQRCode::QRCode.new("http://github.com/")
# With default options specified explicitly
svg = qrcode.as_svg(offset: 0, color: '000', 
                    shape_rendering: 'crispEdges', 
                    module_size: 11)

ANSI¶ ↑

The ANSI renderer will produce as a string with ANSI color codes.

qrcode = RQRCode::QRCode.new("http://github.com/")
# With default options specified explicitly
svg = qrcode.as_ansi_(light: "\033[47m", dark: "\033[40m",
                    fill_character: '  ',
                    quiet_zone_size: 4)

PNG¶ ↑

The library can produce a PNG. Result will be a ChunkyPNG::Image instance.

qrcode = RQRCode::QRCode.new("http://github.com/")
# With default options specified explicitly
png = qrcode.as_png(
          resize_gte_to: false,
          resize_exactly_to: false,
          fill: 'white',
          color: 'black',
          size: 120,
          border_modules: 4,
          module_px_size: 6,
          file: nil # path to write
          )
IO.write("/tmp/github-qrcode.png", png.to_s)

HTML Rendering¶ ↑

In your controller¶ ↑

@qr = RQRCode::QRCode.new( 'https://github.com/whomwah/rqrcode', :size => 4, :level => :h )

In your view¶ ↑

<%= raw @qr.as_html %>

CSS¶ ↑

table {
  border-width: 0;
  border-style: none;
  border-color: #0000ff;
  border-collapse: collapse;
}

td {
  border-left: solid 10px #000;
  padding: 0; 
  margin: 0; 
  width: 0px; 
  height: 10px; 
}

td.black { border-color: #000; }
td.white { border-color: #fff; }

On the console¶ ↑

qr = RQRCode::QRCode.new( 'my string to generate', :size => 4, :level => :h )
puts qr.to_s

Output:

xxxxxxx x  x x   x x  xx  xxxxxxx
x     x  xxx  xxxxxx xxx  x     x
x xxx x  xxxxx x       xx x xxx x
... etc

Doing your own rendering¶ ↑

qr = RQRCode::QRCode.new( 'my string to generate', :size => 4, :level => :h )
qr.modules.each do |row|
    row.each do |col| 
        print col ? "X" : " "
    end
    print "\n"
end

Specifying QR code mode¶ ↑

Sometimes you may want to specify the QR code mode explicitly.

It is done via the mode option. Allowed values are: number, alphanumeric and byte_8bit.

qr = RQRCode::QRCode.new( '1234567890', :size => 2, :level => :m, :mode => :number )

API Documentation¶ ↑

www.rubydoc.info/gems/rqrcode

Resources¶ ↑

wikipedia:: en.wikipedia.org/wiki/QR_Code
Denso-Wave website:: www.denso-wave.com/qrcode/index-e.html
kaywa:: qrcode.kaywa.com

Authors¶ ↑

Original author: Duncan Robertson

Special thanks to the following people for submitting patches:

Contributing¶ ↑

Fork the project
Send a pull request
Don’t touch the .gemspec, I’ll do that when I release a new version

Copyright¶ ↑

MIT License (www.opensource.org/licenses/mit-license.html)