QR code 2005 encoder in Common Lisp

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QR code 2005 encoder in Common Lisp


There are some examples in demo.lisp. More detailed explanations are listed below.

(in-package :cl-qrencode)
(defclass qr-symbol ()
  (matrix modules))
(defun dark-module-p (matrix i j))

QR code is represented by a QR-SYMBOL object in this package, where MATRIX is an MODULES * MODULES array, and the color of each module (dark or light) is indicated by dark-module-p.

(use-package :cl-qrencode)
(defun encode-symbol (text &key (version 1) (level :level-m) (mode nil)))
(defun encode-symbol-bytes (bytes &key (version 1) (level :level-m) (mode nil)))

encode-symbol encodes TEXT into a QR-SYMBOL object. VERSION may be adapted to accommodate the encoding data. LEVEL is the error correction level, which should be one of :level-l, :level-m, :level-q, or :level-h. For most of the time, MODE should be left nil.

(defun encode-png (text &key (fpath "qrcode.png") (version 1) (level :level-m)
                   (mode nil) (pixsize 9) (margin 8)))

This package also supports writing QR-SYMBOL into png files. PIXSIZE is number of pixels for each QR-SYMBOL module, MARGIN is number of pixels for each side of the QRcode quiet zone.


Run via ASDF and test-op, (asdf:test-system '#:cl-qrencode), or manually using (cl-qrencode-test:run-all-tests) once the cl-qrencode-test has been loaded.

The tests require the lisp-unit library to be installed.


Copyright (c) 2011-2014 jnjcc,

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version.

Dependencies (2)

  • lisp-unit
  • zpng

Dependents (0)

    • GitHub
    • Quicklisp