# Third-Party Notices
flexaudio (Copyright (c) 2026 tubome / Studio Sadola, MIT) bundles, statically links,
or dynamically links against third-party software. This document collects the
notices and license terms that must accompany binary and source distributions of
flexaudio and its component crates.
The list below is generated from `cargo metadata` for the workspace. Optional /
platform-specific dependencies (Windows `windows-*`, macOS `objc2-*`, Linux
`pipewire`/`libspa`, ONNX Runtime, etc.) are only pulled in — and only need to be
reproduced — on the platforms / feature sets that use them.
---
## 1. Bundled assets (shipped inside the binary)
### Silero VAD model — `silero_vad.onnx`
`flexaudio-vad` embeds the Silero VAD ONNX model
(`crates/flexaudio-vad/assets/silero_vad.onnx`) into the compiled artifact via
`include_bytes!`. The model weights are therefore present in every binary that
links `flexaudio-vad`, and this notice MUST be reproduced in distributions.
- Project: Silero VAD — https://github.com/snakers4/silero-vad
- Copyright (c) 2020-present Silero Team
- License: MIT
```
MIT License
Copyright (c) 2020-present Silero Team
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
```
> NOTE: Confirmed against upstream. The Silero VAD `LICENSE` on the `master`
> branch (https://github.com/snakers4/silero-vad/blob/master/LICENSE) reads
> "Copyright (c) 2020-present Silero Team" under the MIT License; the block above
> is reproduced verbatim from it. The vendored model is Silero VAD **v6** (see
> `crates/flexaudio-vad/src/lib.rs`).
---
## 2. Statically linked native libraries
### ONNX Runtime (via `ort` 2.0.0-rc.12, `download-binaries` feature)
`flexaudio-vad` runs the Silero VAD model through the `ort` crate. With the
`download-binaries` feature enabled, the build downloads a prebuilt **Microsoft
ONNX Runtime** binary and links it into the artifact. ONNX Runtime is therefore
**redistributed inside `flexaudio-vad` binaries** and its notices MUST accompany
distributions.
- Project: ONNX Runtime — https://github.com/microsoft/onnxruntime
- Copyright (c) Microsoft Corporation
- License: MIT
```
MIT License
Copyright (c) Microsoft Corporation
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
```
**ONNX Runtime version:** `ort` 2.0.0-rc.12 statically links **Microsoft ONNX
Runtime `v1.24.2`**. This is pinned by `ort-sys` 2.0.0-rc.12: every prebuilt-binary
download URL in its `build/download/dist.txt` points at the pyke CDN path
`https://cdn.pyke.io/0/pyke:ort-rs/ms@1.24.2/<target>` (verified in the vendored
crate source `ort-sys-2.0.0-rc.12/build/download/dist.txt`; `ms@1.24.2` is the
Microsoft ONNX Runtime 1.24.2 release).
ONNX Runtime bundles its own third-party code; its complete notices live in ONNX
Runtime's `ThirdPartyNotices.txt` at the matching tag — this is the authoritative
notice and **MUST accompany any binary that statically links ONNX Runtime**:
- https://github.com/microsoft/onnxruntime/blob/v1.24.2/ThirdPartyNotices.txt
- raw: https://raw.githubusercontent.com/microsoft/onnxruntime/v1.24.2/ThirdPartyNotices.txt
Ship that file alongside the `flexaudio-vad` binary (or paste its full text
here). Its components, grouped by the license each is provided under **as stated
in that file** (transcribed from tag `v1.24.2`; the pinned file governs the exact
terms of each), are:
- **Apache-2.0** — onnx, oneDNN (intel/dnnl), TensorFlow, google/benchmark,
DMLC common codebase, DLPack, JDAI-CV/DNNLibrary, google/flatbuffers,
abseil-cpp, Android Open Source Project, huggingface/transformers,
msgpack-python, tensorflow/tensorboard, google/sentencepiece, OpenSSL,
pthreads4w, TensorFlow.js, Intel neural-compressor, neural-speed, KleidiAI
- **MIT** — Microsoft GSL, Microsoft Cognitive Toolkit (CNTK), HalideIR,
HowardHinnant/date, onnx/onnx-tensorrt, microsoft/wil, nlohmann/json,
dcleblanc/SafeInt, lanpa/tensorboardX, gtest-ios-framework, emsdk,
react-native, dlfcn-win32, Tencent/rapidjson, microsoft/mimalloc,
nvidia/cutlass (MurmurHash3 via SMHasher's MIT license; MurmurHash itself is
public domain)
- **BSD-3-Clause** — protocolbuffers/protobuf, pybind/pybind11, NumPy, Caffe2
(in PyTorch), FreeBSD getopt.c, google/googletest, Scikit-learn, google/re2,
google/glog, Open MPI, coremltools, google/XNNPACK, Triton Inference Server &
Client, FlashAttention, dawn
- **BSD-2-Clause** — Caffe, pytorch/cpuinfo, mpi4py
- **MPL-2.0** — Eigen (the one weak-copyleft component; its obligations are met
by shipping ONNX Runtime's `ThirdPartyNotices.txt`, which reproduces the MPL text)
- **BSL-1.0 (Boost)** — Boost / boostorg/boost
- **Zlib** — madler/zlib
- **ISC** — cerberus
- **HPND** — Python Imaging Library (PIL / Pillow)
- **NCSA (Univ. of Illinois)** — LLVM Compiler Infrastructure
- **Intel Simplified Software License** — Intel Math Kernel Library (Intel MKL)
- **Public Domain / Unlicense** — SQLite, libb64, G3log
> NOTE: The CPU build `ort` downloads does not exercise every component above
> (e.g. Intel MKL / CUDA / TensorRT / CoreML / XNNPACK paths depend on which
> execution providers are compiled in), but ONNX Runtime's own `ThirdPartyNotices.txt`
> enumerates the full set, so the complete file is reproduced by reference to stay
> conservative. This inventory was transcribed from ONNX Runtime `v1.24.2`
> `ThirdPartyNotices.txt` (the release `ort` 2.0.0-rc.12 downloads); that pinned
> file remains authoritative for the exact license text of each component.
The Rust glue crates around ONNX Runtime are themselves permissively licensed:
- `ort` 2.0.0-rc.12 — MIT OR Apache-2.0 (https://github.com/pykeio/ort)
- `ort-sys` 2.0.0-rc.12 — MIT OR Apache-2.0
---
## 3. Dynamically linked native libraries (Linux, runtime)
### PipeWire / SPA (libpipewire-0.3 / libspa-0.2)
On **Linux**, `flexaudio-os-linux` captures system / per-process audio through
PipeWire, linking against the system's `libpipewire-0.3` and `libspa-0.2`
shared libraries at runtime via the `pipewire` / `libspa` Rust bindings. These
**system libraries are NOT bundled** by flexaudio — they are provided by the end
user's Linux distribution.
- Project: PipeWire — https://gitlab.freedesktop.org/pipewire/pipewire
- License (libpipewire / libspa runtime libraries): **MIT** for most of the
tree; some SPA plugins are LGPL-2.1+. flexaudio links the MIT-licensed
`libpipewire-0.3` / `libspa-0.2` client libraries dynamically.
- The Rust binding crates `pipewire`, `pipewire-sys`, `libspa`, `libspa-sys`
(v0.10.x) are MIT.
> NOTE: Because PipeWire is linked **dynamically** and supplied by the OS, no
> PipeWire object code is redistributed in flexaudio binaries. If you choose to
> bundle PipeWire shared objects yourself (e.g. a self-contained Linux package),
> reproduce the applicable PipeWire MIT/LGPL notices for the exact `.so` files
> you ship, and honor LGPL-2.1+ relinking obligations for any LGPL components.
---
## 4. Permissive Rust dependencies (compiled in)
All remaining workspace dependencies are permissively licensed (MIT / Apache-2.0
/ BSD / ISC / Zlib / Unlicense and dual-license combinations thereof). Their
copyright notices and license texts are available in each crate's source on
crates.io / the respective repositories. The table is the deduplicated transitive
dependency set resolved with `--all-features` (so it is a superset of any single
platform / feature build).
| aho-corasick | Unlicense OR MIT |
| alsa | Apache-2.0 OR MIT |
| alsa-sys | MIT |
| annotate-snippets | MIT OR Apache-2.0 |
| anstream | MIT OR Apache-2.0 |
| anstyle | MIT OR Apache-2.0 |
| anstyle-parse | MIT OR Apache-2.0 |
| anstyle-query | MIT OR Apache-2.0 |
| anstyle-wincon | MIT OR Apache-2.0 |
| audio-core | MIT OR Apache-2.0 |
| audioadapter | MIT OR Apache-2.0 |
| audioadapter-buffers | MIT OR Apache-2.0 |
| audioadapter-sample | MIT OR Apache-2.0 |
| autocfg | Apache-2.0 OR MIT |
| base64 | MIT OR Apache-2.0 |
| bindgen | BSD-3-Clause |
| bitflags | MIT OR Apache-2.0 |
| block2 | MIT |
| bumpalo | MIT OR Apache-2.0 |
| byteorder | Unlicense OR MIT |
| bytes | MIT |
| cc | MIT OR Apache-2.0 |
| cesu8 | Apache-2.0 OR MIT |
| cexpr | Apache-2.0 OR MIT |
| cfg-expr | MIT OR Apache-2.0 |
| cfg-if | MIT OR Apache-2.0 |
| cfg_aliases | MIT |
| clang-sys | Apache-2.0 |
| clap | MIT OR Apache-2.0 |
| clap_builder | MIT OR Apache-2.0 |
| clap_derive | MIT OR Apache-2.0 |
| clap_lex | MIT OR Apache-2.0 |
| colorchoice | MIT OR Apache-2.0 |
| combine | MIT |
| convert_case | MIT |
| cookie-factory | MIT |
| coreaudio-rs | MIT OR Apache-2.0 |
| cpal | Apache-2.0 |
| crossbeam-utils | MIT OR Apache-2.0 |
| ctor | Apache-2.0 OR MIT |
| ctrlc | MIT OR Apache-2.0 |
| dasp_sample | MIT OR Apache-2.0 |
| dispatch2 | Zlib OR Apache-2.0 OR MIT |
| either | MIT OR Apache-2.0 |
| equivalent | Apache-2.0 OR MIT |
| errno | MIT OR Apache-2.0 |
| find-msvc-tools | MIT OR Apache-2.0 |
| futures-core | MIT OR Apache-2.0 |
| futures-task | MIT OR Apache-2.0 |
| futures-util | MIT OR Apache-2.0 |
| getrandom | MIT OR Apache-2.0 |
| glob | MIT OR Apache-2.0 |
| hashbrown | MIT OR Apache-2.0 |
| heck | MIT OR Apache-2.0 |
| hmac-sha256 | ISC |
| hound | Apache-2.0 |
| http | MIT OR Apache-2.0 |
| httparse | MIT OR Apache-2.0 |
| indexmap | Apache-2.0 OR MIT |
| is_terminal_polyfill | MIT OR Apache-2.0 |
| itertools | MIT OR Apache-2.0 |
| itoa | MIT OR Apache-2.0 |
| jni | MIT OR Apache-2.0 |
| jni-sys | MIT OR Apache-2.0 |
| jni-sys-macros | MIT OR Apache-2.0 |
| js-sys | MIT OR Apache-2.0 |
| libc | MIT OR Apache-2.0 |
| libloading | ISC |
| libspa | MIT |
| libspa-sys | MIT |
| linux-raw-sys | Apache-2.0 WITH LLVM-exception OR Apache-2.0 OR MIT |
| log | MIT OR Apache-2.0 |
| lzma-rust2 | Apache-2.0 |
| mach2 | BSD-2-Clause OR MIT OR Apache-2.0 |
| matrixmultiply | MIT OR Apache-2.0 |
| memchr | Unlicense OR MIT |
| minimal-lexical | MIT OR Apache-2.0 |
| napi | MIT |
| napi-build | MIT |
| napi-derive | MIT |
| napi-derive-backend | MIT |
| napi-sys | MIT |
| ndarray | MIT OR Apache-2.0 |
| ndk | MIT OR Apache-2.0 |
| ndk-context | MIT OR Apache-2.0 |
| ndk-sys | MIT OR Apache-2.0 |
| nix | MIT |
| nom | MIT |
| num-complex | MIT OR Apache-2.0 |
| num-derive | MIT OR Apache-2.0 |
| num-integer | MIT OR Apache-2.0 |
| num-traits | MIT OR Apache-2.0 |
| num_enum | BSD-3-Clause OR MIT OR Apache-2.0 |
| num_enum_derive | BSD-3-Clause OR MIT OR Apache-2.0 |
| objc2 | MIT |
| objc2-audio-toolbox | Zlib OR Apache-2.0 OR MIT |
| objc2-core-audio | Zlib OR Apache-2.0 OR MIT |
| objc2-core-audio-types | Zlib OR Apache-2.0 OR MIT |
| objc2-core-foundation | Zlib OR Apache-2.0 OR MIT |
| objc2-encode | MIT |
| objc2-foundation | MIT |
| once_cell | MIT OR Apache-2.0 |
| once_cell_polyfill | MIT OR Apache-2.0 |
| ort | MIT OR Apache-2.0 |
| ort-sys | MIT OR Apache-2.0 |
| percent-encoding | MIT OR Apache-2.0 |
| pin-project-lite | Apache-2.0 OR MIT |
| pipewire | MIT |
| pipewire-sys | MIT |
| pkg-config | MIT OR Apache-2.0 |
| portable-atomic | Apache-2.0 OR MIT |
| portable-atomic-util | Apache-2.0 OR MIT |
| primal-check | MIT OR Apache-2.0 |
| proc-macro-crate | MIT OR Apache-2.0 |
| proc-macro2 | MIT OR Apache-2.0 |
| quote | MIT OR Apache-2.0 |
| rawpointer | MIT OR Apache-2.0 |
| realfft | MIT |
| regex | MIT OR Apache-2.0 |
| regex-automata | MIT OR Apache-2.0 |
| regex-syntax | MIT OR Apache-2.0 |
| ring | Apache-2.0 AND ISC |
| ringbuf | MIT OR Apache-2.0 |
| rtrb | MIT OR Apache-2.0 |
| rubato | MIT |
| rustc-hash | Apache-2.0 OR MIT |
| rustfft | MIT OR Apache-2.0 |
| rustix | Apache-2.0 WITH LLVM-exception OR Apache-2.0 OR MIT |
| rustls | Apache-2.0 OR ISC OR MIT |
| rustls-pki-types | MIT OR Apache-2.0 |
| rustls-webpki | ISC |
| rustversion | MIT OR Apache-2.0 |
| same-file | Unlicense OR MIT |
| semver | MIT OR Apache-2.0 |
| serde_core | MIT OR Apache-2.0 |
| serde_derive | MIT OR Apache-2.0 |
| serde_spanned | MIT OR Apache-2.0 |
| shlex | MIT OR Apache-2.0 |
| slab | MIT |
| smallvec | MIT OR Apache-2.0 |
| socks | MIT OR Apache-2.0 |
| strength_reduce | MIT OR Apache-2.0 |
| strsim | MIT |
| subtle | BSD-3-Clause |
| syn | MIT OR Apache-2.0 |
| system-deps | MIT OR Apache-2.0 |
| target-lexicon | Apache-2.0 WITH LLVM-exception |
| thiserror | MIT OR Apache-2.0 |
| thiserror-impl | MIT OR Apache-2.0 |
| tokio | MIT |
| toml | MIT OR Apache-2.0 |
| toml_datetime | MIT OR Apache-2.0 |
| toml_edit | MIT OR Apache-2.0 |
| toml_parser | MIT OR Apache-2.0 |
| toml_writer | MIT OR Apache-2.0 |
| tracing | MIT |
| tracing-core | MIT |
| transpose | MIT OR Apache-2.0 |
| unicode-ident | (MIT OR Apache-2.0) AND Unicode-3.0 |
| unicode-segmentation | MIT OR Apache-2.0 |
| unicode-width | MIT OR Apache-2.0 |
| untrusted | ISC |
| ureq | MIT OR Apache-2.0 |
| ureq-proto | MIT OR Apache-2.0 |
| utf8-zero | MIT OR Apache-2.0 |
| utf8parse | Apache-2.0 OR MIT |
| version-compare | MIT |
| visibility | Zlib OR MIT OR Apache-2.0 |
| walkdir | Unlicense OR MIT |
| wasi | Apache-2.0 WITH LLVM-exception OR Apache-2.0 OR MIT |
| wasm-bindgen | MIT OR Apache-2.0 |
| wasm-bindgen-futures | MIT OR Apache-2.0 |
| wasm-bindgen-macro | MIT OR Apache-2.0 |
| wasm-bindgen-macro-support | MIT OR Apache-2.0 |
| wasm-bindgen-shared | MIT OR Apache-2.0 |
| web-sys | MIT OR Apache-2.0 |
| webpki-roots | CDLA-Permissive-2.0 |
| winapi | MIT OR Apache-2.0 |
| winapi-i686-pc-windows-gnu | MIT OR Apache-2.0 |
| winapi-util | Unlicense OR MIT |
| winapi-x86_64-pc-windows-gnu | MIT OR Apache-2.0 |
| windowfunctions | MIT |
| windows | MIT OR Apache-2.0 |
| windows-core | MIT OR Apache-2.0 |
| windows-implement | MIT OR Apache-2.0 |
| windows-interface | MIT OR Apache-2.0 |
| windows-link | MIT OR Apache-2.0 |
| windows-result | MIT OR Apache-2.0 |
| windows-sys | MIT OR Apache-2.0 |
| windows-targets | MIT OR Apache-2.0 |
| windows_aarch64_gnullvm | MIT OR Apache-2.0 |
| windows_aarch64_msvc | MIT OR Apache-2.0 |
| windows_i686_gnu | MIT OR Apache-2.0 |
| windows_i686_gnullvm | MIT OR Apache-2.0 |
| windows_i686_msvc | MIT OR Apache-2.0 |
| windows_x86_64_gnu | MIT OR Apache-2.0 |
| windows_x86_64_gnullvm | MIT OR Apache-2.0 |
| windows_x86_64_msvc | MIT OR Apache-2.0 |
| winnow | MIT |
| zeroize | Apache-2.0 OR MIT |
> Note on `webpki-roots` (CDLA-Permissive-2.0) and `unicode-ident`
> (Unicode-3.0): these are build-time / TLS-root data dependencies pulled by
> `ort`'s `download-binaries` HTTP fetch and by proc-macro tooling; they are not
> part of the runtime audio path but appear in the full dependency graph.
---
## How this file was produced
The permissive dependency table is the deduplicated output of:
```
cargo metadata --format-version 1 --all-features
```
Regenerate after dependency changes. Sections 1-3 (bundled / statically linked /
dynamically linked native code) are curated by hand because they carry
redistribution obligations that a flat crate list does not capture.