Microphone

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session.mic is the low-level audio input: raw frames and a voice-activity signal. If you want text, use session.transcription instead. Reach for mic when you need the audio itself, like recording a clip or running your own audio processing. Both subscriptions need the MICROPHONE permission in your manifest, or the phone rejects them with PERMISSION_NOT_DECLARED.

Raw audio

session.mic.onAudioChunk((chunk) => {
  // chunk.data is base64-encoded PCM or LC3.
  buffer.push(chunk.data);
});

Each AudioChunkData has:

Field	Type	Notes
`data`	`string`	Base64-encoded audio. PCM or LC3 depending on the phone’s mic mode.
`sampleRate`	`number?`	Sample rate, when reported.
`format`	`string?`	The encoding, when reported.

Voice activity

onVoiceActivity fires when the user starts and stops speaking, without giving you the audio:

session.mic.onVoiceActivity(({ status }) => {
  // status: true while speaking, false when silent.
  if (status) session.display.render([{type: "text", id: "msg", box: {x: 0, y: 0, w: 576, h: 288}, text: "Listening…"}]);
});

Cleaning up

Both methods return an unsubscribe function, and stop() tears down everything this module owns:

const off = session.mic.onAudioChunk(handler);
off();              // drop this one

session.mic.stop(); // drop all of them

session.mic.hasPermission reports whether MICROPHONE is declared in your manifest, not whether the user granted the OS prompt. If they denied it, the subscription succeeds but no chunks arrive.

mic, transcription, and translation are independent. Subscribing to raw audio does not give you transcripts, and vice versa. Audio output (playback and text-to-speech) lives on session.speaker.

Getting Started

Core Concepts

UI Layer

Display

Audio & Speech

Sensors & Input

Camera

Phone & System

Data

Reference

Raw audio

Voice activity

Cleaning up

​Raw audio

​Voice activity

​Cleaning up

Raw audio

Voice activity

Cleaning up