fsound

fsound is an open-source, cross-platform library for real-time audio processing and synthesis. It focuses on providing a modular, low-latency environment suitable for music software, game audio, and educational use. The library aims to be portable across Windows, macOS, and Linux, with bindings to higher-level languages.

Core features include a modular DSP graph, a CPU-friendly scheduler, real-time audio I/O, multi-channel support, and a plugin interface for extending functionality. It offers prebuilt building blocks such as oscillators, filters, envelope generators, and effects, as well as a mechanism to define custom DSP blocks.

Architecture: fsound stores processing graphs as nodes connected by streams. Each node implements a processing callback. The engine ensures sample-accurate timing, supports sample-accurate automation, and provides a host API for integrating external plugins. A scripting layer exposes the API to languages such as Lua and Python, enabling rapid experimentation.

Development and licensing: fsound is maintained by a community of volunteers and is distributed under an open-source license. Contributions span core engine work, documentation, example projects, and bindings. The project emphasizes clean documentation, test coverage, and portability across platforms.