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.travis Script for generating "display-name" metadata Apr 12, 2018
build-aux Update gnulib Jun 6, 2017
contrib Remove capsign from the emacs mode Apr 4, 2017
doc Merge PR #527 Jun 4, 2018
extra/generate-display-names Add "display-name" metadata May 28, 2018
gnulib Import the manywarnings module May 3, 2018
liblouis Check index before writing to result->chars Jun 6, 2018
m4 Make sure the m4 directory is not pruned by git Aug 3, 2016
man Generate a man page for lou_tableinfo Aug 31, 2017
python Removed pass1Only from rest of code, including. Removed yaml test. Feb 23, 2018
tables Delete Liblouisutdml specific tables Aug 19, 2018
tests Merge pull request #589 from liblouis/test-ueb-michael-robin Aug 6, 2018
tools Merge PR #527 Jun 4, 2018
windows Increase the version number Jun 4, 2018
.clang-format UseTab: Always Oct 3, 2017
.dir-locals.el Add org-mode to .dir-locals.el Mar 5, 2018
.dockerignore Make docker build again Jul 11, 2017
.gitignore Script for generating "display-name" metadata Apr 12, 2018
.travis.yml Fix .travis.yml: test-suite.log was not printed anymore after a failure Dec 19, 2017
ANNOUNCEMENT Fix a typo in the announcement Jun 4, 2018
AUTHORS Update the AUTHORS file May 31, 2018
COPYING State in the README that the library is licensed under LGPL and the Nov 5, 2009
COPYING.LESSER Move the library to LGPLv2.1 Jun 20, 2016
ChangeLog Update email of Lars Bjørndal Apr 25, 2017
Dockerfile Update the Dockerfile according to best practices Sep 20, 2017
Dockerfile.dev make distwin32: also run tests Jun 6, 2017
Doxyfile Document most of the test functions for Doxygen Dec 14, 2017
HACKING Add a link to an explanation re libtool versioning Mar 5, 2018
License.md Make sure github lists liblouis as licensed under LGPLv2.1 Dec 13, 2016
Makefile.am Convert the format-sources target to a user defined automake target Oct 3, 2017
NEWS Added news entry. Jun 21, 2018
README Mention the --with-yaml option in the README Mar 6, 2017
README.md Add a symlink so that github displays the README is a nice way May 20, 2014
README.windows Changed some of the wording Jun 28, 2018
TODO removed todo items that are now documented on website. Sep 2, 2014
autogen.sh Move the library to LGPLv2.1 Jun 20, 2016
configure.ac Increase the version number Jun 4, 2018
liblouis.pc.in * liblouis.pc.in: Added a variable called 'tablesdir'. Jan 17, 2008
libyaml_mingw.patch Build libyaml from source Sep 9, 2016



Build Status

Liblouis is an open-source braille translator and back-translator named in honor of Louis Braille. It features support for computer and literary braille, supports contracted and uncontracted translation for many languages and has support for hyphenation. New languages can easily be added through tables that support a rule- or dictionary based approach. Tools for testing and debugging tables are also included. Liblouis also supports math braille (Nemeth and Marburg).

Liblouis has features to support screen-reading programs. This has led to its use in two open-source screenreaders, NVDA and Orca. It is also used in some commercial assistive technology applications for example by ViewPlus.

Liblouis is based on the translation routines in the BRLTTY screenreader for Linux. It has, however, gone far beyond these routines. In Linux and Mac OSX it is a shared library, and in Windows it is a DLL.

Liblouis is free software licensed under the GNU LGPLv2.1+ (see the file COPYING.LESSER).

The command line tools, are licensed under the GNU GPLv3+ (see the file COPYING).


For documentation, see the liblouis documentation (either as info file, html, txt or pdf) in the doc directory. For examples of translation tables, see en-us-g2.ctb, en-us-g1.ctb, chardefs.cti, and whatever other files they may include in the tables directory. This directory contains tables for many languages. The Nemeth files will only work with the sister library liblouisutdml.


After unpacking the distribution tarball go to the directory it creates. You now have the choice to compile liblouis for either 16- or 32-bit unicode. By default it is compiled for the former. To get 32-bit Unicode run configure with --enable-ucs4.

After running ./configure run make and then make install. You must have root privileges for the installation step.

This will produce the liblouis library and the programs lou_allround (for testing the library), lou_checkhyphens, lou_checktable (for checking translation tables), lou_debug (for debugging translation tables), lou_translate (for extensive testing of forward and backwards translation) and lou_trace (for tracing if individual translations). For more details see the liblouis documentation.

If you wish to have man pages for the programs you might want to install help2man before running configure.

If you want to run the test suite with make check you should install libyaml as that will enable extensive tests on the tables. If you want to skip those tests you can do so by running configure --without-yaml.


You can contribute to Liblouis in several different ways:

  • If you have comments, questions, or want to use your knowledge to help others, come join the conversation on either the mailing list or on IRC. You can reach us at liblouis-liblouisxml@freelists.org or in channel #liblouis on irc:irc.oftc.net.

  • To report a problem or request a feature, please file an issue.

  • Of course, we welcome pull requests and patches.

Finally, if you want to see what we have for the future and learn more about our release cycles, all this information is detailed on the wiki

Release Notes

For notes on the newest and older releases see the file NEWS.


Liblouis was begun in 2002 largely as a business decision by ViewPlus. They believed that they could never have good braille except as part of an open source effort and knew that John Boyer was dying to start just such a project. So ViewPlus did start it on the agreement that they would give a small monthly stipend to John Boyer that allowed him to pay for sighted assistants. While ViewPlus has not contributed much to the coding, it certainly has contributed and continues to contribute to liblouis through that support of John Boyer.