Flutter API outline

How it works

Flutter talks to the Recording SDK through a MethodChannel, and listens on EventChannels where needed. The plugin talks to Android / iOS native code, which talks to the shared C++ engine.

POC API outline

• create / start / stop / destroy
• setGainDb
• sampleRate
• getInputLatencyMs / getOutputLatencyMs / getRoundTripLatencyMs
• setUserMonitorEnabled / userMonitorEnabled
• getOutputRoute / getOutputRouteName / refreshAudioRoute / routeChanges
• setBluetoothMonitorMode / getBluetoothMonitorMode
• isMonitorAudible / bluetoothWarningRecommended

Alpha and January outline

Session

• loadBackingTrack(path)
• startRecording(dryPath, ...)
• stopRecording()
• pause() / resume() / reset() / reinit()

Time and seek (see Appendix B)

• getPositionMs / position stream
• seekToMs(ms)
• seekToLyricLine(index) when lyric timings are loaded

Effects and mix

• setPreset(name)
• setVocalVolume / setMusicVolume
• setFxIntensity / setReverb / setDelay / setEq(low, mid, high)
• setLatencyOffsetMs(-250…+250)

Pitch and score

• loadMelodyJson(path or string)
• pitch / sharp-flat-in-tune / score streams or getters
• setPitchCorrectionEnabled / strength (v1)

Export

• exportMix(path, format: m4a|mp3, bitrate)
• export progress / completion / error events to Flutter

Noise reduction (January add-on)

• setNoiseGateEnabled / amount