A software-mixing sound engine
clownaudio is a stereo sound engine, capable of playing and mixing sounds in a
variety of formats.
Supported formats include…
clownaudio is a ‘full stack’ sound engine, meaning that it handles everything
from decoding to playback - the user just has to provide it with sound data to
process.
That said, clownaudio’s internals are modular, so you can easily extract
its mixer and use it as part of your own audio system if needed.
In order to support a range of audio formats, clownaudio leverages numerous
open-source libraries, dubbed ‘decoding backends’. These libraries include…
| Library | Format | Licence | Built-in |
|---|---|---|---|
| libvorbis | Ogg Vorbis | BSD | No |
| stb_vorbis | Ogg Vorbis | Public-domain/MIT | Yes |
| dr_mp3 | MP3 | Public-domain/MIT-0 | Yes |
| libopus | Opus | BSD | No |
| libFLAC | FLAC | BSD | No |
| dr_flac | FLAC | Public-domain/MIT-0 | Yes |
| dr_wav | WAV | Public-domain/MIT-0 | Yes |
| libsndfile | Various (includes Ogg Vorbis, FLAC, WAV, AIFF, and others) | LGPL 2.1 | No |
| libopenmpt | Various (includes .it, .mod, .s3m, .xm, .mptm, and many others) | BSD | No |
| libxmp | Various (includes .it, .mod, .s3m, .xm, and many others) | LGPL 2.1 | Yes |
| libxmp-lite | .it, .mod, .s3m, .xm | MIT | Yes |
| PxTone | PxTone Music/PxTone Noise | Custom (appears to be permissive) | Yes |
| snes_spc | SNES SPC | LGPL 2.1 | Yes |
| oswrapper_audio | Various (OS dependent) | BSD0 | Yes |
clownaudio aims to be bloat-free and dependency-free: each decoding backend can
be toggled at compile-time, and an effort is made to provide multiple backends
for individual formats, to allow the user a choice between standard libraries
(such as libvorbis), and lighter built-in libraries (such as stb_vorbis).
In addition, clownaudio can utilise one of the following libraries to handle
audio playback:
| Library | Licence | Built-in |
|---|---|---|
| Cubeb | ISC | No |
| CoreAudio | zlib | Yes |
| miniaudio | Public-domain/MIT-0 | Yes |
| PortAudio | MIT | No |
| SDL1.2 | LGPL 2.1 | No |
| SDL2 | zlib | No |
clownaudio is built with CMake - both shared and static libraries can be
produced. Built libraries can be accessed via pkg-config and CMake’sfind_package.
As an alternative, CMake projects can embed clownaudio directly, usingadd_subdirectory.
Example software using clownaudio can be found in the examples directory.
The CLI example’s Makefile demonstrates linking clownaudio with pkg-config,
and its CMakeLists.txt file demonstrates linking with find_package and
embedding with add_subdirectory.
An effort is made to keep clownaudio’s build system requirements simple, so that
projects wishing to embed its source files directly and bypass its CMake build
system can do so. See the CLI example’s Makefile.old for an example of this.
PKGBUILD files for MSYS2 and Arch Linux are provided in the packages
directory.
clownaudio itself is under the zlib licence.
Be aware that libraries used by the various backends are subject to
their own licences.