NOTICE
July 21, 2026 · View on GitHub
Opal ("Play everything"; binary and config directory named opal) is a native,
local-first media runtime. This file lists the third-party components Opal
links against, bundles, or downloads on demand, along with their licenses.
License of Opal's own source
Opal's own source code is licensed under GPL-3.0. This copyleft choice is driven primarily by Opal's linkage against libmpv, which is distributed under the GPL by most platforms. Because the combined binary links GPL-covered mpv, a permissive license for the whole work is not defensible, and GPL-3.0 is the standard, compatible choice for an mpv-linked media application. This decision can be revisited by the maintainer if the mpv linkage situation changes (for example, switching to a strictly LGPL-built mpv or replacing the playback backend).
Third-party components
| Component | License | Notes |
|---|---|---|
| mpv (libmpv) | GPLv2+ / LGPLv2.1+ (commonly GPL as distro-built) | Core video/audio playback via linkSystemLibrary("mpv"). GPL linkage is the dominant licensing constraint and the reason Opal ships under GPL-3.0. |
| libtorrent-rasterbar | BSD-3-Clause | Magnet/.torrent streaming, wrapped by src/torrent_wrapper.cpp → libtorrent_wrapper.so to isolate the C++ ABI. |
| dvui | MIT | Immediate-mode GUI (debpalash/dvui fork), vendored as a git dependency in build.zig.zon; uses the dvui_sdl2 backend. |
| onnxruntime | MIT | Local ML inference and the ort/ocr_ort.c PP-OCR pipeline via linkSystemLibrary("onnxruntime"). |
| SDL2 | zlib | Window/input/rendering backend; bundled (X11-only) on macOS, or system SDL2 (-fsys=sdl2) for Wayland. |
| sqlite3 | Public Domain | Local unified database at ~/.config/opal/opal.db (watch history, AI memory, config, caches). |
| sqlite-vec | Apache-2.0 OR MIT (dual) | Vendored C in src/core/sqlite/sqlite-vec.c; vec0 virtual table with float[768] embeddings for AI memory vector search. |
| zig-lib-icons (TVG icons) | MIT | UI icons, git dependency (nat3github/zig-lib-icons) in build.zig.zon. |
| whisper.cpp (ggml) | MIT | STT via whisper-cli + ggml models, downloaded from HuggingFace at runtime (not vendored). |
| sherpa-onnx (k2-fsa) | Apache-2.0 | Optional STT/TTS models (Whisper-tiny, Piper-VITS, Kokoro, streaming Zipformer), downloaded on demand from GitHub releases. |
| yt-dlp | Unlicense | YouTube and playlist extraction; system or auto-downloaded binary, used via mpv's ytdl-hook. |
| qBittorrent search engine plugins | MIT (some adapted from GPL qBittorrent plugins; original terms preserved — see engines/LICENSE_NOTICE) | Bundled Python scrapers in engines/engines/*.py, run via the engines/nova2.py subprocess harness. |
| streamlink | BSD-2-Clause | Live-stream HLS resolution (Twitch/Kick/etc.), invoked as an external Python tool via scripts/streamlink_resolve.py. |
macOS system frameworks
On macOS, Opal links Apple system frameworks (CoreServices, AVFoundation, Cocoa, and others) provided by the operating system under Apple's standard SDK and platform license terms.
Attribution
Each component remains under its own license and copyright. Refer to the upstream projects for full license texts. Nothing in this NOTICE modifies the terms under which those components are distributed.