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)

0.10.0 (Feb 11, 2016)

0.9.0 (Jan 3, 2016)

0.8.1 (Jan 3, 2016)

0.8.0 (Dec 18, 2015)

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.

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

Authors

Original author: Duncan Robertson

Special thanks to the following people for submitting patches:

Contributing

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