libqrencode - a fast and compact QR Code encoding library

Attention: This repository contains the development version of libqrencode. See https://fukuchi.org/works/qrencode/ for the official stable releases. At this moment, the latest stable release is version 4.0.2.

GENERAL INFORMATION

Libqrencode is a fast and compact library for encoding data in a QR Code, a 2D symbology that can be scanned by handy terminals such as a smartphone. The capacity of QR Code is up to 7000 digits or 4000 characters and has high robustness.

Libqrencode accepts a string or a list of data chunks then encodes in a QR Code symbol as a bitmap array. While other QR Code applications generate an image file, using libqrencode allows applications to render QR Code symbols from raw bitmap data directly. This library also contains a command-line utility outputs QR Code images in various formats.

SPECIFICATION

Libqrencode supports QR Code model 2, described in JIS (Japanese Industrial Standards) X0510:2004 or ISO/IEC 18004. Most of features in the specification are implemented such as:

Numeric, alphabet, Japanese kanji (Shift-JIS) or any 8 bit code can be embedded
Optimized encoding of a string
Structured-append of symbols
Micro QR Code (experimental)

Currently the following features are not supported:

ECI and FNC1 mode
QR Code model 1 (deprecated)

INSTALL

Requirements

While the command-line utility and some test programs use libpng or SDL 2.0, the libqrencode library itself has no dependencies. You can skip compiling tests and/or tools if you want not to install programs using SDL or PNG.

Compile & install

If there is no "configure" script in the source code directory, run "autogen.sh" at first to generate it - this is mandatory if you downloaded the source from GitHub. Some additional software is needed to complete this process. For example, in Ubuntu, the following packages are needed:

autoconf
automake
autotools-dev
libtool
pkg-config
libpng12-dev

You can skip this process if you have "configure" script already (typically when you downloaded the source tarball from fukuchi.org.)

Now you are ready to compile the library and tool. Type the following commands:

./configure
make
sudo make install
sudo ldconfig

This compiles and installs the library and header file to the appropriate directories: by default, /usr/local/lib and /usr/local/include. You can change the destination directory by passing some options to the configure script. Run "./configure --help" to see the list of options.

It also installs a command line tool "qrencode" to /usr/local/bin. If you want not to build it, give "--without-tools" option to the configure script.

If the configure script does not work well, try to use CMake.

cmake .
make

When you want to build the test programs, give "--with-tests" option to configure, or "-DWITH_TESTS=YES" to cmake.

USAGE

Basic usages of this library are written in the header file (qrencode.h). You can generate a manual of the library by using Doxygen, or see

https://fukuchi.org/works/qrencode/manual/index.html

WARNINGS

The library is distributed WITHOUT ANY WARRANTY.

Micro QR Code support is EXPERIMENTAL.

Be careful to use the command line tool (qrencode) if it is used by a web application (e.g. CGI script). For example, giving "-s" option with a large number to qrencode may cause DoS. The parameters should be checked by the application.

LICENSING INFORMATION

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

CONTACT

Visit the homepage at:

https://fukuchi.org/works/qrencode/

for new releases. The git repository is available at:

https://github.com/fukuchi/libqrencode

Please mail any bug reports, suggestions, comments, and questions to:

Kentaro Fukuchi kentaro@fukuchi.org

or submit issues to:

https://github.com/fukuchi/libqrencode/issues

ACKNOWLEDGMENTS

QR Code is registered trademarks of DENSO WAVE INCORPORATED in JAPAN and other countries.

Reed-Solomon encoder included in this library is originally taken from FEC library developed by Phil Karn (KA9Q) and distributed under the terms of the GNU LGPL, then rewritten by Kentaro Fukuchi. Copyright (C) 2002, 2003, 2004, 2006 Phil Karn, KA9Q

NANKI Haruo - improved lower-case characters encoding
Katsumi Saito - SPEC file
Philippe Delcroix - improved mask evaluation
Yusuke Mihara - structured-append support
David Dahl - DPI and SVG support patch
Adam Shepherd - bug fix patch of the mask evaluation
Josef Eisl (@zapster) - EPS support patch
Colin (@moshen) - ANSI support patch
Ralf Ertzinger - ASCII support patch
Yutaka Niibe (@gniibe)- various bug fix patches
Dan Storm (@Repox) - SVG support patch
Lennart Poettering (@mezcalero) - improved text art patch
Yann Droneaud - improved input validation patch
Viona - bug fix patch for string splitting
Daniel Dörrhöfer (@d4ndo) - RLE option, some bug fixes, Travis configuration
Greg Hart - PNG32 support patch
@siggi-heltau - bug fix patch
Tobias Klauser (@tklauser) - bug fix patch, XPM support patch
Robert Petersen (@ripetersen) - added ability to read input data from a file
@Oblomov - improved SVG support patch
Michał Górny (@mgorny) - reverse mappings of UTF8 and ANSIUTF8, build script fixes
@EckoEdc - MinGW support patch
Sebastian Buchwald (@UniQP) - Various code cleanups
André Klitzing (@misery) - CMake support
Alexey Nikolaev (@aleksey-nikolaev) - improved CMake support
Vilppu Vuorinen (@vilppuvuorinen) - improved CMake support
@vanillahsu - bug fix patch
@Ation - bug fix patch
Jonathan Bennett - Addedd "--inline" option to qrencode
András Veres-Szentkirályi - ANSI256UTF8 support
@sdf5 - improved CMake support
Lonnie Abelbeck (@abelbeck) - bug fix patch
Shigeyuki Hirai, Paul Janssens, wangsai, Gavan Fantom, Matthew Baker, Rob Ryan, Fred Steinhaeuser, Terry Burton, @chisj, @vlad417, Petr, Hassan Hajji, Emmanuel Blot, ßlúèÇhîp, Heiko Becker, Gavin Andresen, David Binderman, @ralgozino, Sean McMurray, Vlad Bespalov (@win32asm), Antenore Gatta, Yoshimichi Inoue, Sunil Maganally, Norman Gray, Danomi Manchego, @minus7, Ian Sweet, @qianchenglenger, Ronald Michaels, Yuji Ueno, Jakub Wilk, @KangLin, @c-273, @thebunnyrules - bug report / suggestion / typo fixes

ideastudio/libqrencode