Ham Voicing includes free and open-source software written by other people. Their copyright notices and licence terms are reproduced below.
Codec2 1.2.0 (github.com/drowe67/codec2) provides the low-bitrate digital voice codec used for M17. A 25-file subset of the voice sources is compiled into the app; FreeDV and the OFDM modems are not included.
Codec2 is free software. You may modify it, and reverse engineer your modifications for the purpose of debugging them, under the terms of the LGPL-2.1. The complete licence text ships inside the app and is available from the Codec2 project.
libgsm 1.0.22 (quut.com/gsm) provides the GSM 06.10 full-rate codec used for EchoLink audio. A 14-source subset is compiled into the app, built without WAV49 framing.
“Any use of this software is permitted provided that this notice is not removed and that neither the authors nor the Technische Universitaet Berlin are deemed to have made any representations as to the suitability of this software for any purpose nor are held responsible for any defects of this software. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.”
Ham Voicing’s M17 implementation is original code written from the published M17 specification and verified against the M17 Project’s reference test vectors. No M17 Project source code is compiled into the app.
The app is built with Flutter and uses open-source Dart packages. The full list of those packages and their licences is shown inside the app under About → Licences & Notices → Flutter and Dart packages.
If you have a question about the licensing of any component, email [email protected].