tts-react
provides a hook (useTts
) and component (TextToSpeech
) to convert text to speech. In most cases you want the hook so you can use custom styling on the audio controls.
By default tts-react
uses the SpeechSynthesis
and SpeechSynthesisUtterance
API's. You can fallback to the HTMLAudioElement
API by providing a fetchAudioData
prop to the hook or component.
Install
npm i react react-dom tts-react
Documentation
morganney.github.io/tts-react
Example
Hook
import { useTts } from 'tts-react'
import type { TTSHookProps } from 'tts-react'
interface HookExampleProps extends TTSHookProps {
highlight?: boolean
}
const HookExample = ({ children, highlight = false }: HookExampleProps) => {
const { ttsChildren, state, onPlay, onStop, onPause } = useTts({
children,
markTextAsSpoken: highlight
})
return (
<div>
{state.isReady && (
<>
<button onClick={onPlay}>Play</button>
<button onClick={onPause}>Pause</button>
<button onClick={onStop}>Stop</button>
</>
)}
{ttsChildren}
</div>
)
}
const App = () => {
return <HookExample highlight>Some text to be spoken.</HookExample>
}
Component
import { TextToSpeech, Positions, Sizes } from 'tts-react'
const App = () => {
return (
<TextToSpeech
markTextAsSpoken
align="vertical"
size={Sizes.SMALL}
position={Positions.TL}>
<p>Some text to be spoken.</p>
</TextToSpeech>
)
}
useTts
The hook returns the internal state of the audio being spoken, getters/setters of audio attributes, callbacks that can be used to control playing/stopping/pausing/etc. of the audio, and modified children
if using markTextAsSpoken
. The parameters accepted are described in the Props section. The response object is described by the TTSHookResponse
type.
const useTts = ({
lang,
voice,
children,
markColor,
markBackgroundColor,
onError,
onMuted,
fetchAudioData,
autoPlay = false,
markTextAsSpoken = false
}: TTSHookProps): TTSHookResponse => {
return {
get,
set,
state,
spokenText,
ttsChildren,
onPlay,
onStop,
onPause,
onReset,
onPlayPause,
onMuted: onMutedHandler
}
}
interface TTSHookResponse {
set: {
lang: (value: string) => void
rate: (value: number) => void
pitch: (value: number) => void
volume: (value: number) => void
preservesPitch: (value: boolean) => void
}
get: {
lang: () => string
rate: () => number
pitch: () => number
volume: () => number
preservesPitch: () => boolean
}
state: TTSHookState
spokenText: string
onPlay: () => void
onStop: () => void
onPause: () => void
onReset: () => void
onMuted: () => void
onPlayPause: () => void
ttsChildren: ReactNode
}
interface TTSHookState {
boundary: BoundaryUpdate
isPlaying: boolean
isPaused: boolean
isMuted: boolean
isError: boolean
isReady: boolean
}
interface TTSBoundaryUpdate {
word: string
startChar: number
endChar: number
}
fetchAudioData
Using fetchAudioData
will bypass SpeechSynthesis
and use the HTMLAudioElement
.
(spokenText: string) => Promise<TTSAudioData>
When using fetchAudioData
it must return TTSAudioData
which has the following shape:
interface PollySpeechMark {
end: number
start: number
time: number
type: 'word'
value: string
}
interface TTSAudioData {
audio: string
marks?: PollySpeechMark[]
}
The audio
property must be a URL that can be applied to HTMLAudioElement.src
, including a data URL. If using markTextAsSpoken
then you must also return the marks
that describe the word boundaries. SpeechMarks
have the same shape as the Speech Marks used by Amazon Polly, with the restriction that they must be of type: 'word'
.
Props
Most of these are supported by the useTts
hook, but those marked with an asterisk are exclusive to the TextToSpeech
component.
*
Only applies to TextToSpeech
component.
Name | Required | Type | Default | Description |
---|
children | yes | ReactNode | none | Provides the text that will be spoken. |
lang | no | string | The one used by SpeechSynthesisUtterance.lang . | Sets the SpeechSynthesisUtterance.lang . Overrides voice when set and voice.lang does not match lang . |
voice | no | SpeechSynthesisVoice | None or the voice provided by audio from TTSAudioData . | The voice heard when the text is spoken. Calling set.lang may override this value. |
autoPlay | no | boolean | false | Whether the audio of the text should automatically be spoken when ready. |
markTextAsSpoken | no | boolean | false | Whether the word being spoken should be highlighted. |
markColor | no | string | none | Color of the text that is currently being spoken. Only applies with markTextAsSpoken . |
markBackgroundColor | no | string | none | Background color of the text that is currently being spoken. Only applies with markTextAsSpoken . |
fetchAudioData | no | (text: string) => Promise<TTSAudioData> | none | Function to return the optional SpeechMarks[] and audio URL for the text to be spoken. See fetchAudioData for more details. |
* allowMuting | no | boolean | true | Whether an additional button will be shown on the component that allows muting the audio. Calls onMuted when clicked. |
onMuted | no | (wasMuted: boolean) => void | none | Callback when the user clicks the mute button shown from allowMuting being enabled. Can be used to toggle global or local state like whether autoPlay should be enabled. |
onError | no | (evt: CustomEvent<string>) => void | none | Callback when there is an error of any kind playing the spoken text. The error message (if any) will be provided in evt.detail . |
* align | no | 'horizontal' | 'vertical' | 'horizontal' | How to align the controls within the TextToSpeech component. |
* size | no | 'small' | 'medium' | 'large' | 'medium' | The relative size of the controls within the TextToSpeech component. |
* position | no | 'topRight' | 'topLeft' | 'bottomRight' | 'bottomLeft' | 'topRight' | The relative positioning of the controls within the TextToSpeech component. |