Acknowledgments and copyright notices

UltraVox™ is a trademark of Noldus Information Technology BV. UltraVox XT would not be what it is without the use of third-party software. This page lists software libraries and other software products used in UltraVox XT and where you can find license and compliance information and/or acknowledgments for that product.

The PDF of the copyright notices are stored in

C:\Program Files\Noldus\UltraVox XT 4\Documentation\Legal\Acknowledgments.

Asio

Cross-platform C++ library for network and low-level I/O programming. Version 1.32.0. Copyright © 2003-2024 Christopher M. Kohlhoff. Distributed under the Boost Software License, Version 1.0.

https://github.com/chriskohlhoff/asio/tree/master

https://github.com/chriskohlhoff/asio/blob/master/asio/LICENSE_1_0.txt

bb-audio

Library for recording, handling and analyzing audio files. Version 1.6.1. Copyright © 2025 Brain Builders BV.

https://brain.builders/

bb-license

Library for handling license restrictions. Version 2.2.0. Copyright © 2025 Brain Builders BV.

https://brain.builders/

ed25519

Public-key signature system used for verifying audio files and licenses.

Copyright © 2015 Orson Peters. Distributed under the zlib license.

https://github.com/orlp/ed25519

https://github.com/orlp/ed25519/blob/master/license.txt

{fmt}

Open-source string formatting library for logging. Version 11.0.2.

Copyright © 2012 - present, Victor Zverovich and {fmt} contributors.

https://github.com/fmtlib/fmt

https://github.com/fmtlib/fmt/blob/master/LICENSE

GCC

Integrated distribution of compilers for several major programming languages.

Copyright © 2023 The Free Software Foundation, Inc. This program is distributed under the GNU General Public License.

https://www.fsf.org

https://www.gnu.org/licenses

muFFT

Library for performing the Fast Fourier Transform (FFT) in one or two dimensions.

Copyright © 2015 Hans-Kristian Arntzen.

https://github.com/Themaister/muFFT

https://github.com/Themaister/muFFT/blob/master/COPYING

nlohmann json

Class of JSON libraries used for reading license files. Version 3.11.3.

Copyright © 2013-2024 Niels Lohmann.

https://github.com/nlohmann/json

https://github.com/nlohmann/json/blob/develop/LICENSE.MIT

OpenSSL

Toolkit for general-purpose cryptography and secure communication. Version 3.4.0. OpenSSL is licensed under the Apache License 2.0.

Copyright © 2025 OpenSSL.

https://openssl-library.org/

https://github.com/openssl/openssl/blob/master/LICENSE.txt

PortAudio

PortAudio is a cross-platform, open-source C language library for real-time audio input and output. Version 19.7. PortAudio is licensed under MIT license.

https://github.com/PortAudio

https://portaudio.com/license.html

Qt

Qt is a cross-platform application development framework for creating graphical user interfaces. Version 6.7.3. Qt used in UltraVox XT development is licensed under a commercial license.

https://doc.qt.io/qt-6/licensing.html 

Simpleini

Simpleini is a cross-platform library that provides a simple API to read and write ini-style configuration files. Version 4.20. Simpleini is licensed under the MIT License.

Copyright © 2006-2024 Brodie Thiesfield.

https://github.com/brofield/simpleini

https://github.com/brofield/simpleini/blob/master/LICENCE.txt

Spdlog

Spdlog is a C++ logging library. Version 1.15.0. Spdlog is licensed under the MIT License.

Copyright © 2016 Gabi Melman.  

https://github.com/gabime/spdlog

https://github.com/gabime/spdlog/blob/v1.x/LICENSE

Ultravox Library

Software development kit for all UltraVox XT functionality. Version 1.1.1. Copyright © 2025 Brain Builders BV.

https://brain.builders/