README.md (5220B)
libcubeb - Cross-platform Audio I/O Library

libcubeb is a cross-platform C library for high and low-latency audio input/output. It provides a simple, consistent API for audio playback and recording across multiple platforms and audio backends. It is written in C, C++ and Rust, with a C ABI and Rust bindings. While originally written for use in the Firefox Web browser, a number of other software projects have adopted it.
Features
- Cross-platform support: Windows, macOS, Linux, Android, and other platforms
- Versatile: Optimized for low-latency real-time audio applications, or power efficient higher latency playback
- A/V sync: Latency compensated audio clock reporting for easy audio/video synchronization
- Full-duplex support: Simultaneous audio input and output, reclocked
- Device enumeration: Query available audio devices
- Audio processing for speech: Can use VoiceProcessing IO on recent macOS
Supported Backends & status
| Backend | Support Level | Platform version | Notes | |-------------------|-----------------|--------------------|--------------------------------------------------| | PulseAudio (Rust) | Tier-1 | | Main Linux desktop backend | | AudioUnit (Rust) | Tier-1 | | Main macOS backend | | WASAPI | Tier-1 | Windows >= 7 | Main Windows backend | | AAudio | Tier-1 | Android >= 8 | Main Android backend for most devices | | OpenSL | Tier-1 | Android >= 2.3 | Android backend for older devices | | OSS | Tier-2 | | | | sndio | Tier-2 | | | | Sun | Tier-2 | | | | WinMM | Tier-3 | Windows XP | Was Tier-1, Firefox minimum Windows version 7. | | AudioTrack | Tier-3 | Android < 2.3 | Was Tier-1, Firefox minimum Android version 4.1. | | ALSA | Tier-3 | | | | JACK | Tier-3 | | | | KAI | Tier-3 | | | | PulseAudio (C) | Tier-4 | | Was Tier-1, superseded by Rust | | AudioUnit (C++) | Tier-4 | | Was Tier-1, superseded by Rust |
Tier-1: Actively maintained. Should have CI coverage. Critical for Firefox.
Tier-2: Actively maintained by contributors. CI coverage appreciated.
Tier-3: Maintainers/patches accepted. Status unclear.
Tier-4: Deprecated, obsolete. Scheduled to be removed.
Note that the support level is not a judgement of the relative merits of a backend, only the current state of support, which is informed by Firefox's needs, the responsiveness of a backend's maintainer, and the level of contributions to that backend.
Building
Prerequisites
- CMake 3.15 or later
- Non-ancient MSVC, clang or gcc, for compiling both C and C++
- Platform-specific audio libraries (automatically detected)
- Optional but recommended: Rust compiler to compile and link more recent backends for macOS and PulseAudio
Quick build
git clone https://github.com/mozilla/cubeb.git
cd cubeb
cmake -B build
cmake --build build
Better build with Rust backends
git clone --recursive https://github.com/mozilla/cubeb.git
cd cubeb
cmake -B build -DBUILD_RUST_LIBS=ON
cmake --build build
Platform-Specific Notes
Windows: Supports Visual Studio 2015+ and MinGW-w64. Use -G "Visual Studio 16 2019" or -G "MinGW Makefiles".
macOS: Requires Xcode command line tools. Audio frameworks are automatically linked.
Linux: Development packages for desired backends:
# Ubuntu/Debian
sudo apt-get install libpulse-dev libasound2-dev libjack-dev
# Fedora/RHEL
sudo dnf install pulseaudio-libs-devel alsa-lib-devel jack-audio-connection-kit-devel
Android: Use with Android NDK. AAudio requires API level 26+.
Testing
Run the test suite:
cd build
ctest
Use the interactive test tool:
./cubeb-test
License
Licensed under an ISC-style license. See LICENSE for details.
Contributing
Contributions are welcome! Please see the contribution guidelines and check the issue tracker.