Omniphony

A real-time spatial / object-based audio rendering engine. Omniphony takes multichannel and object audio and renders it — with VBAP — to any speaker layout or to binaural headphones, in real time. Open source, GPL-3.0.

• 🎧 Hear it on headphones — binaural output (HRTF + ITD + live head-tracking), no surround rig required.
• 🔊 Render to any layout — stereo, 5.1, 7.1, 7.1.4 and beyond, via VBAP.
• 🧩 Pluggable decoders — a small, stable ABI (bridge_api) loads decoder bridges at runtime; bring your own format.
• 🛰️ Live control + 3D visualization — Omniphony Studio supervises the engine over OSC.

Hear it in 2 minutes — no media player needed

The engine ships a self-contained demo: a reference WAV decoder bridge plus a short multichannel clip. From a fresh clone:

cd omniphony-renderer
./scripts/demo.sh            # builds the engine, then plays the demo on your headphones

scripts/demo.sh binaurally renders assets/demo/spatial-demo.wav — a source sweeping around you with an overhead tone — straight to your headphones. No external player, no proprietary decoder. Other modes:

./scripts/demo.sh speakers   # 7.1.4 speaker render instead of binaural
./scripts/demo.sh file       # no audio device? pipe raw float to ffplay

Frontends

Omniphony is the engine; you can drive it three ways:

Frontend	What it is
orender CLI	The standalone engine binary — render a stream or file to speakers, headphones, or a file/pipe. The demo above uses it.
Omniphony Studio	Desktop app: 3D visualization, live control, metering, layout management. Prebuilt bundles on the releases page (Linux / Windows / macOS).
mpv-omniphony	The mpv media player with an opt-in spatial decoder (--ad=orender) that renders through the engine instead of downmixing. (usage guide · source)

How it works

omniphony-renderer loads a format bridge at runtime (a .so / .dll implementing the bridge_api ABI), decodes the input to PCM + object metadata, and renders it:

• VBAP object → speaker-feed rendering, with loadable speaker layouts and precomputed VBAP tables
• real-time output backends — pipewire (Linux), asio (Windows), CoreAudio (macOS), plus a non-realtime file / stdout / FIFO backend
• binaural headphone output — HRTF, ITD, early reflections, live head-tracking
• metadata and metering over OSC

The reference bridge in omniphony-renderer/reference_bridge/ (used by the demo) is the smallest example of how to add your own decoder. See omniphony-renderer/BRIDGE_API.md.

Components

omniphony-renderer — the engine

The core engine (executable: orender) and its supporting crates:

• renderer — VBAP engine, layouts, binaural, OSC output, runtime config
• audio_output — PipeWire / ASIO / CoreAudio / file backends
• audio_input — live PCM / bridge input
• bridge_api — the stable ABI for external decoder bridges
• reference_bridge — a reference WAV/PCM decoder bridge (powers the demo)
• spdif — IEC 61937 / S/PDIF parsing
• sys — platform integration (incl. Windows service)

Start with omniphony-renderer/QUICKSTART.md.

omniphony-studio — supervision & control

A desktop app that does not render audio itself; it connects to the engine over OSC to visualize objects in a 3D scene, monitor runtime state, and control selected live parameters. It accepts several OSC input conventions (cartesian, identifier-in-address, spherical azimuth/elevation/distance, explicit removal).

Repository layout

• omniphony-renderer/ — engine, CLI, crates, reference bridge
• omniphony-studio/ — supervision / visualization app
• docs/ — frontend usage guides (e.g. mpv-omniphony)
• assets/ — demo clip, logo, captures
• scripts/ — helpers

License

GPL-3.0-or-later — see LICENSE. Decoder bridges are loaded at runtime via dlopen and may be licensed separately.

Support

If Omniphony is useful to you, you can support development with a donation — it helps maintain and improve the suite.