Speech Synthesis

Speak text aloud through the platform synthesizer

One.SpeechSynthesis speaks text aloud on iOS and Android and through speechSynthesis in browsers. It has speak(text, options?), stop(), pause(), resume(), isSpeaking(), getAvailableVoices(), and the maxInputLength property. It is separate from One.Speech, which is microphone dictation.

import { One } from 'one'

One.SpeechSynthesis.speak('Hello', {
  language: 'en-US',
  rate: 1,
  onDone: () => console.log('finished'),
})

await One.SpeechSynthesis.stop()

speak queues while another utterance speaks; each call carries its own onStart, onDone, onStopped, and onError callbacks, and every utterance ends with exactly one of done, stopped, or error. stop() clears the queue and the interrupted utterance reports stopped. pause() and resume() hold and continue synthesis on iOS and resolve quietly on Android. isSpeaking() stays true while paused. getAvailableVoices() resolves { identifier, language, name, quality } entries, where quality is 'default' or 'enhanced'. maxInputLength is the longest text one speak accepts. pitch defaults to 1, rate to 1, volume to 1, and voice to a system voice matching language.

On iOS physical devices speech is silent when the silent switch is on. On web, cancellation maps to onStopped and every voice reports 'default' quality. Without a synthesizer, speak does nothing, reads report empty, and callbacks never fire.