| Component | Licence | Used for |
|---|---|---|
| mpv (libmpv) | LGPL-2.1-or-later | Playback engine (Windows, macOS) |
| FFmpeg | LGPL-2.1-or-later | Demuxing and decoding (Windows, macOS) |
| libplacebo | LGPL-2.1-or-later | Video rendering |
| FriBidi, GNU libiconv | LGPL-2.1-or-later | Subtitle text shaping and encodings |
| shaderc, SPIRV-Cross, SPIRV-Tools, Vulkan loader | Apache-2.0 | Shader compilation for Direct3D 11 |
| glslang | BSD-3-Clause and others | Shader compilation |
| libass | ISC | Styled subtitles |
| FreeType | FreeType License | Font rendering |
| HarfBuzz | MIT | Text shaping |
| dav1d | BSD-2-Clause | AV1 decoding |
| Little CMS, libjpeg-turbo, zlib-ng, Brotli, zstd, bzip2, libpng, uchardet, libunibreak, Fontconfig, Expat | Permissive (MIT, BSD, IJG, zlib, MPL-1.1 for uchardet) | Support libraries |
| .NET runtime, WPF | MIT | Windows app framework |
| Microsoft.Data.Sqlite, SQLitePCLRaw, SQLite | MIT, Apache-2.0, public domain | Local library database |
| Whisper.net, whisper.cpp | MIT | On-device speech recognition |
| Velopack | MIT | Windows installer and updates |
| AndroidX Media3 (ExoPlayer), Jetpack Compose | Apache-2.0 | Android app |
The full licence texts are installed with the app (in the licenses folder next to Kymelo on Windows) and are included in the source archive below.
Playback engine source code (LGPL)
The Windows playback engine combines LGPL-2.1-or-later components with Apache-2.0 shader compilers, so the engine library as a whole is distributed under the GNU Lesser General Public License version 3 or later. It is a separate, replaceable library: you may swap libmpv-2.dll for your own compatible build.
For at least three years after each release we provide the complete corresponding source code of the engine: every component's source at the exact version shipped, Kymelo's build configuration and the build scripts. It is published with each release on the download server as kymelo-engine-source.tar.zst (its SHA-256 is recorded in the release's engine manifest), or email support@kymeloapp.com and we will send it to you.
Speech models
Kymelo can download OpenAI's Whisper models (MIT licence), converted by the whisper.cpp project, from Hugging Face when you choose to generate subtitles. They are not included in the app.