This feature is not Baseline because it does not work in some of the most widely-used browsers.
The SpeechRecognitionAlternative interface of the Web Speech API represents a single word that has been recognized by the speech recognition service.
SpeechRecognitionAlternative.transcript Read only
Returns a string containing the transcript of the recognized word.
SpeechRecognitionAlternative.confidence Read only
Returns a numeric estimate between 0 and 1 of how confident the speech recognition system is that the recognition is correct.
This code is excerpted from our Speech color changer example.
recognition.onresult = (event) => {
// The SpeechRecognitionEvent results property returns a SpeechRecognitionResultList object
// The SpeechRecognitionResultList object contains SpeechRecognitionResult objects.
// It has a getter so it can be accessed like an array
// The first [0] returns the SpeechRecognitionResult at position 0.
// Each SpeechRecognitionResult object contains SpeechRecognitionAlternative objects
// that contain individual results.
// These also have getters so they can be accessed like arrays.
// The second [0] returns the SpeechRecognitionAlternative at position 0.
// We then return the transcript property of the SpeechRecognitionAlternative object
const color = event.results[0][0].transcript;
diagnostic.textContent = `Result received: ${color}.`;
bg.style.backgroundColor = color;
};
| Specification |
|---|
| Web Speech API> # speechreco-alternative> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
SpeechRecognitionAlternative |
33 | 79 | No | No | 14.1 | 33 | No | No | 14.5 | 2.0 | 4.4.3 | 14.5 |
confidence |
33 | 79 | No | No | 14.1 | 33 | No | No | 14.5 | 2.0 | 4.4.3 | 14.5 |
transcript |
33 | 79 | No | No | 14.1 | 33 | No | No | 14.5 | 2.0 | 4.4.3 | 14.5 |
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https://developer.mozilla.org/en-US/docs/Web/API/SpeechRecognitionAlternative