SpeechRecognitionPhrase

Instance properties

SpeechRecognitionPhrase.boost Read only: A floating pointing number representing the amount of boost you want to give the corresponding phrase.
SpeechRecognitionPhrase.phrase Read only: A string containing a word or phrase you want boosted in terms of the engine's bias towards it.

The following code first creates an array containing the phrases to boost and their boost values. We convert this data to an ObservableArray of SpeechRecognitionPhrase objects by mapping the original array to SpeechRecognitionPhrase() constructor calls:

js

const phraseData = [
  { phrase: "azure", boost: 5.0 },
  { phrase: "khaki", boost: 3.0 },
  { phrase: "tan", boost: 2.0 },
];

const phraseObjects = phraseData.map(
  (p) => new SpeechRecognitionPhrase(p.phrase, p.boost),
);

After creating a SpeechRecognition instance, we can then plug our contextual biasing phrases into it by setting the phraseObjects array as the value of the SpeechRecognition.phrases property:

js

const recognition = new SpeechRecognition();
recognition.continuous = false;
recognition.lang = "en-US";
recognition.interimResults = false;
recognition.processLocally = true;
recognition.phrases = phraseObjects;

// …

This code is excerpted from our on-device speech color changer (run the demo live). See Using the Web Speech API for a full explanation.