Mix connected audio-bearing composition layers or extract the soundtrack from a video source, then export WAV or MP3 with master volume, fades, and normalization.
Where: Flowgen → Add → Export → Audio Render — Connect a native composition, video, or editor document to Audio Render
Key ideas
- Audio-bearing layers: Composition input mixes standalone audio layers plus video layers with audible source audio. Video In extracts the soundtrack from a connected source clip, so the node can make a WAV/MP3 without a compositor graph. The Tracks stat shows qualifying sources; the Render button reads 'No audio in source' if none do.
- Master controls: Master Volume (0–2×), linear Fade In / Fade Out (seconds), and a Normalize-peaks toggle that scales the final mix to ~-0.1 dBFS. Each layer's own volume, trim, and playback rate are honored.
- Format & fidelity: Choose WAV (16-bit PCM) or MP3, plus sample rate (22.05k/44.1k/48k) and Mono/Stereo. MP3 adds a bitrate picker (128–320 kbps). Est. Size updates live and warns red over 50 MB.
- Pitch-preserving path: If any layer needs a non-unity playback rate with preserve-pitch, the render switches from the fast offline mix to a real-time capture path (the same native time-stretcher the live preview uses) for cleaner tonal/voice output.
- Audio Render card: AudioRenderNode uses the generic shared-card path. Mix connected audio/video layers or extract a source clip soundtrack into a downloadable WAV or MP3 result.
- Properties sidebar: genOutputNodes.tsx
- Opened surfaces: Rendered audio player; Add to canvas; Paste to Replace
Steps
- Add Audio Render. Connect a composition to Composition In, or connect a source clip to Video In when you only need to extract its soundtrack.
- Pick Format (WAV / MP3); for MP3 also choose a Bitrate. Set Sample Rate and Mono/Stereo.
- Tune Master Volume, and add Fade In / Fade Out seconds if needed; toggle Normalize peaks to even out loudness.
- Confirm the Duration / Tracks / Est. Size stats, then click Render Audio and watch the progress fill.
- Use the in-card audio player to preview, then ⋯ → Download to save the WAV/MP3.
Audio Render controls and presets
- Add path: Flowgen → Add → Sound → Audio Render.
- Card: AudioRenderNode.
- Properties: genOutputNodes.tsx.
- Controls: Composition In (audio/video layers); Video In (single source clip soundtrack); duration; WAV/MP3; sample rate; channels; bitrate; master volume; normalize; fades.
- Opened surfaces: Rendered audio player; Add to canvas; Paste to Replace.
FAQ
What if my composition has no audio?
The button shows 'No audio in source' and stays disabled while the source is connected. The renderer can still emit deterministic silence as a fallback, but you'll normally add at least one audio or volumed video layer first.
Why does MP3 sometimes come out as WebM?
MP3 encoding goes through MediaRecorder; if the browser can't encode audio/mpeg it falls back to audio/webm (opus). WAV is always available as a lossless fallback.