Voice capture

VoiceCaptureSession records from the microphone and transcribes speech in the browser, for spoken food, meal, or restaurant searches. It runs entirely in the browser: no token, scope, or origin enablement needed. It doesn't depend on React or any other UI framework.

Capture and transcribe

Create one session for the lifetime of the component that owns it, and subscribe before starting so the UI can show permission, recording, and processing states. Call start() from a user gesture, such as a microphone button, and stop() when the user presses stop.

import { VoiceCaptureError, VoiceCaptureSession } from '@januaryai/web-sdk';

const voice = new VoiceCaptureSession();
const unsubscribe = voice.subscribe((snapshot) => render(snapshot)); // state, audioLevel, durationMs, partialTranscript

// First gesture: the microphone button.
export async function onMicPressed() {
  try {
    await voice.start({ language: 'en-US' });
  } catch (error) {
    if (error instanceof VoiceCaptureError) showVoiceError(error.code);
  }
}

// Second gesture: the stop button.
export async function onStopPressed() {
  const { transcript } = await voice.stop();
  if (transcript) setQuery(transcript);
}

// When the component or page goes away.
export function onUnmount() {
  unsubscribe();
  voice.dispose();
}

Call stop() only while voice.snapshot.state is recording. cancel() discards the capture at once; dispose() also removes every subscriber. VoiceCaptureError.code is one of unsupported, permissionDenied, microphoneUnavailable, recordingFailed, invalidState, or cancelled.

Browser support

A result has durationMs and, when the browser recognized speech, transcript. Check voice.isSupported before showing the microphone, and voice.isTranscriptionSupported when you need text. Speech recognition isn't available in every browser and can depend on operating-system services, so keep a text field too.

Permissions and privacy

Microphone access needs a secure context such as HTTPS; localhost works for development. Ask only after the user presses the microphone button, show a recording indicator with stop and cancel buttons, and explain how to allow the microphone again after a denial.

The SDK doesn't keep, return, or upload the recording. It discards audio chunks during capture and releases the microphone when capture stops or is canceled. The browser's speech-recognition service controls how speech is processed.

The Search screen of the React example app shows this flow.