qrencode.cr

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Crystal bindings for libqrencode.

Installation

Add this to your application's shard.yml:

dependencies:
  qrencode:
    github: woodruffw/qrencode.cr
    branch: master

libqrencode is required. On Debian-based systems, it can be installed via:

$ sudo apt install libqrencode-dev

Usage

QRencode provides methods for generating a QR symbol from various inputs (ASCII/UTF8 text, numerics, Kanji (shift-JIS), etc).

It does not perform the task of rendering QR symbol data to an image format (e.g., PNG) -- it's up to you (or a client library) to do that.

require "qrencode"

qr = QRencode::QRcode.new("this is my input string")

qr.version
qr.width
qr.data

qr.each_row do |row|
  # each row is `width` bytes
  row.each do |byte|
    if QRencode::Util.black? byte
      print "B"
    else
      print "W"
    end
  end
  puts
end

Check out the examples/ directory.

Contributing

  1. Fork it (https://github.com/woodruffw/qrencode/fork)
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request

Contributors