OPEN-SOURCE LICENSES
Open-source licenses
As of 2026-10-09
The ClassNori teacher console and student client (Windows, macOS), the Android apps and the web applications include the open-source and third-party components listed below. Each component is copyrighted by its respective owner and distributed under the license shown. We are grateful to the developers who publish this software.
The full license texts are included in THIRD-PARTY-LICENSES.md and the licenses\ folder of the installation directory. This page is the web version of that document.
Components with obligations beyond attribution
| Component | Version | License | Copyright |
|---|---|---|---|
| FFmpeg | 7.1.5 (n7.1.5-1-g7d0e842004, build 2026-07-10) | LGPL-3.0 | the FFmpeg developers |
| Video playback in the teacher console for Windows (container demux, H.264/AAC decode) and screen receiving in the student client for Windows (H.264 GPU decode; the same DLLs except avformat). Shipped as shared libraries (DLLs) so you can replace them with another build of the same major version. Contains no GPL or non-free components. The corresponding source for this build is available at the link below. | |||
| FFmpeg (teacher console for macOS) | 7.1.5 (same revision 7d0e842004, built by Eum Ware) | LGPL-2.1-or-later | the FFmpeg developers |
| Video playback in the teacher console for macOS (container demux, H.264/HEVC/AAC decode). Built by us from the same revision as above, with GPL, non-free and version3 components disabled and only macOS system frameworks enabled (VideoToolbox, AudioToolbox, Secure Transport, zlib, bzip2); no third-party libraries are statically included. Shipped as shared libraries (5 dylibs) in Contents/MacOS/ffmpeg inside the app, so you can replace them with another build of the same major version. The build configuration is in Contents/Resources/licenses/ffmpeg/VERSION.txt; the corresponding source is the link below (the same archive as above). | |||
| FFmpeg (Windows builds) — statically linked libraries | various (BSD, MIT, ISC, LGPL-2.1/3, MPL-2.0, Apache-2.0, zlib, FTL) | ||
| libopus · libvpx · libaom · libdav1d · libsvtav1 · librav1e · libjxl · libvorbis · libtheora · libwebp · libopenh264 · libopenjpeg · libmp3lame · libfreetype · libharfbuzz · libfribidi · libass · libxml2 · zlib · xz (lzma) · gmp · libssh · libsrt · libzmq · libbluray · libplacebo · libsoxr · libtwolame · chromaprint · libopencore-amr · openal · SDL2 · libsnappy · libzimg · libkvazaar · libuavs3d · libvvenc · libvmaf · libvpl · libgme · libopenmpt · librist · libaribb24 · libaribcaption · shaderc · fontconfig · lilv · libzvbi and others. The upstream and revision of each library are listed in the build scripts (scripts.d/ of FFmpeg-Builds). | |||
| FFmpeg.AutoGen | 7.1.1 | LGPL-3.0 | Ruslan Balanukhin |
| Bindings for the FFmpeg API, used by the teacher console and the student client for Windows and by the teacher console for macOS. | |||
| WinDivert | 2.2.2 | LGPL-3.0 (dual: GPL-2.0) | basil00 |
| Internet restriction (packet inspection) in the Windows student client. Shipped as separate DLL and driver files so they can be replaced. We elect the LGPL v3 terms. | |||
| Microsoft Cognitive Services Speech SDK | 1.43.0 | Microsoft Software License Terms (proprietary) | Microsoft Corporation |
| Live captions and translation in the teacher console. Not open source; redistributed under Microsoft's terms. Third-party notices: aka.ms/thirdpartynotices | |||
FFmpeg corresponding source
The bundled FFmpeg libraries were built from FFmpeg commit 7d0e842004 (7.1.5) with the FFmpeg-Builds build scripts (https://github.com/BtbN/FFmpeg-Builds/tree/ca65803800fa316b49813e653e57b45808cfc087). The source code (the corresponding source under LGPL v3 section 4) can be downloaded below.
FFmpeg 7.1.5 source — commit 7d0e842004 (tar.gz, about 16 MB)Teacher console and student client (Windows, macOS)
| Component | Version | License | Copyright |
|---|---|---|---|
| Avalonia (Avalonia, .Desktop, .Themes.Fluent, .Fonts.Inter, .Skia) | 11.3.21 | MIT | The AvaloniaUI Project |
| SkiaSharp / HarfBuzzSharp (via Avalonia.Skia) | MIT | Microsoft Corporation, Xamarin Inc., Mono contributors | |
| CommunityToolkit.Mvvm | 8.4.2 | MIT | .NET Foundation and Contributors |
| Concentus | 2.2.2 | BSD-3-Clause | Xiph.Org Foundation, Skype Limited, CSIRO, Microsoft, Jean-Marc Valin and others |
| Google.Protobuf | 3.34.1 | BSD-3-Clause | Google Inc. |
| gRPC for .NET (Grpc.AspNetCore, Grpc.Net.Client, Grpc.Core.Api, Grpc.Tools) | 2.80.0 | Apache-2.0 | The gRPC Authors |
| NAudio | 2.2.1 | MIT | Mark Heath |
| Vortice.Windows (DXGI, Direct3D11, Direct3D9, Direct2D1, MediaFoundation) | 3.8.3 | MIT | Amer Koleci and Contributors |
| ClosedXML | 0.105.0 | MIT | ClosedXML contributors |
| Docnet.Core | 2.6.0 | MIT | Docnet contributors |
| PDFium (bundled by Docnet.Core) | BSD-3-Clause | The PDFium Authors | |
| PdfSharp | 6.2.0 | MIT | empira Software GmbH |
| Serilog (Extensions.Hosting, Settings.Configuration, Sinks.Console/Debug/File) | Apache-2.0 | Serilog Contributors | |
| Microsoft.Extensions.*, System.*, Microsoft.Win32.SystemEvents | 10.0.x | MIT | Microsoft Corporation |
| rhwp | MIT | Edward Kim | |
| Renders HWP/HWPX documents for the presentation feature of the teacher console. | |||
| NSIS (Nullsoft Scriptable Install System) | zlib/libpng | NSIS contributors | |
| The Windows installer itself. | |||
Android apps
| Component | Version | License | Copyright |
|---|---|---|---|
| AndroidX (core-ktx, appcompat, activity-compose, lifecycle, documentfile) | Apache-2.0 | The Android Open Source Project | |
| Jetpack Compose (ui, ui-graphics, material3, material-icons-extended) | Apache-2.0 | The Android Open Source Project | |
| kotlinx-coroutines-android | 1.8.1 | Apache-2.0 | JetBrains s.r.o. |
| gRPC Java / Kotlin (grpc-stub, grpc-protobuf, grpc-okhttp, grpc-kotlin-stub) | 1.62.2 / 1.4.1 | Apache-2.0 | The gRPC Authors |
| protobuf-kotlin | 3.25.3 | BSD-3-Clause | Google Inc. |
| Bouncy Castle (bcpkix-jdk18on) | 1.78.1 | MIT (Bouncy Castle License) | The Legion of the Bouncy Castle Inc. |
| libopus | BSD-3-Clause | Xiph.Org Foundation, Skype Limited, Octasic, Jean-Marc Valin and others | |
| Audio codec statically linked into the Android apps. | |||
Web (license management, download page, this site)
| Component | Version | License | Copyright |
|---|---|---|---|
| React, React DOM | 19.x | MIT | Meta Platforms, Inc. and affiliates |
| react-router-dom | 7.x | MIT | Remix Software Inc. |
| Tailwind CSS, @tailwindcss/vite | 4.x | MIT | Tailwind Labs Inc. |
| lucide-react | ISC | Lucide Contributors | |
| qrcode | MIT | Ryan Day | |
| Vite | MIT | VoidZero Inc. and Vite contributors | |
| Astro, @astrojs/sitemap | 5.x | MIT | Fred K. Schott and Astro contributors |
| remark-directive, unist-util-visit | MIT | Titus Wormer |
Fonts
| Component | Version | License | Copyright |
|---|---|---|---|
| Inter | SIL Open Font License 1.1 | The Inter Project Authors | |
| UI typeface of the teacher console and student client. | |||
| Pretendard | 1.3.9 | SIL Open Font License 1.1 | Kil Hyung-jin |
| Typeface of this website (served from a CDN). | |||
If you find a missing component or an incorrect entry, please let us know through the contact page. We will correct it after verification.