libkeyfinder is a small C++11 library for estimating the musical key of digital
audio. It is published under the GNU General Public License version 3 or later.

It was written by Ibrahim Shaath who wrote it in 2011 as part of a master's
thesis in computer science. A GUI application to use it is available for macOS
and Windows, however that is no longer maintained and does not build on
contemporary Linux distributions.

In 2020, Ibrahim handed over maintenance of libkeyfinder to the Mixxx DJ
software team who incorporated it into Mixxx as of Mixxx 2.3. If you want to
discuss anything related to libkeyfinder with us, please get in touch on the
Mixxx Zulip chat. Contributions are welcome by opening pull requests and issues
on GitHub.