Render and customize QR codes with a background image

This gem extends rqrcode-rails published by samvincent, supporting the output in either SVG or PNG,

JPEG, and GIF formats and providing new options to set background image combined with QR code image.

Add the following to your Gemfile.

gem 'custom_rqrcode'

If you want to use the PNG, JPEG or GIF format, you will have to have ImageMagick installed on your system. You will also want to add the mini_magick gem to your application's Gemfile.

gem 'mini_magick'

In your controller actions, you could return a QR code that links to the current page like this:

bg_image = Rails.root.join("app").to_s + ActionController::Base.helpers.asset_path("images/bg_image.png")
respond_to do |format|
  format.html
  format.svg  { render :qrcode => request.url, :level => :l, :unit => 10 }
  format.png  { render :qrcode => request.url, :bg => bg_image, :bsize => "200x100", :gravity => "center", :geometry => "+00+20" }
  format.gif  { render :qrcode => request.url }
  format.jpeg { render :qrcode => request.url }
end

In your controller actions, you could generate multiple QR codes on the background

bg_image = Rails.root.join("app").to_s + ActionController::Base.helpers.asset_path("images/bg_image.png")
cqrcode = RQRCode::CQRCode.new
options = {
	:info => "Hi there.",
	:bg   => bg_image
}
cqrcode.generateQRcode(options, :png)
cqrcode.generateQRcode(options, :jpeg)
cqrcode.generateQRcode(options, :gif)

• :size – This controls how big the QR Code will be. Smallest size will be chosen by default. Set to maintain consistent size.
• :level – The error correction level, can be:
  • Level :l 7% of code can be restored
  • Level :m 15% of code can be restored
  • Level :q 25% of code can be restored
  • Level :h 30% of code can be restored (default :h)
• :offset – Padding around the QR Code (e.g. 10)
• :unit – How many pixels per module (e.g. 11)
• :fill – Background color (e.g "ffffff" or :white)
• :color – Foreground color for the code (e.g. "000000" or :black)
• :bg – Background image to be combined with QR code image (e.g. "./img/000.png")
• :bsize – Resize background image (e.g. "300x200")
• :gravity – Location where QR code image will be put on the background image (e.g. "center", "north", "south")
• :geometry – Adjust the position specifically where QR code image will be located on the image (e.g. "+00+10", "-10+30")
• :fsize – Resize final images (e.g. "400x300")
• :fsave – Save final images (e.g. "/images/qrcode/1.png" or "/img/0.jpg")
• :info – A string to be encoded (only for second usage)

This project was modified from samvincent's project rqrcode-rails3

QR codes are encoded by rqrcode