CODEWITHSUNDEEP
iosspeech-recognitionspeech-to-textsfspeechrecognizer
synchronizer
synchronizer

Reputation: 2075

Is it possible to limit SFSpeechRecognizer's vocabulary?

I'd like to use the ios SFSpeechRecognizer to recognize a closed set of words and phrases. Is there a way to specify these and remove all other possibilities? I cannot seem to find a way to do this.

Upvotes: 2

Views: 566

Answers (3)

Crocobag
Crocobag

Reputation: 2340

After some trials and error, the best solution is a mix between Mrsantateam and Giuseppe Garassino's answers.

you can first specify all commands that should be "prioritized" by setting contextualStrings...

var contextualString = ["hello world", "goodbye world"]
recognitionRequest.contextualStrings = contextualString

... And later filter those results in recognitionTask :

recognitionTask = speechRecognizer.recognitionTask(with: recognitionRequest) { result, error in
    var isFinal = false
    
    if let result = result {                
        for transcription in result.transcriptions {
            print("Pondering \(result.bestTranscription.formattedString)")
            if contextualString.contains(transcription.formattedString.lowercased()) {
                print("Found \(transcription.formattedString)")
            }
        }
    }
    
    //...
}

Sample code can be found at https://developer.apple.com/documentation/speech/recognizing_speech_in_live_audio if you want to play with it and test its limits

Upvotes: 0

Mrsantateam
Mrsantateam

Reputation: 171

You can try to use contextualStrings property of SFSpeechAudioBufferRecognitionRequest to set high priority or to set some words that are not in vocabulary. For more info look here: https://developer.apple.com/documentation/speech/sfspeechrecognitionrequest/1649391-contextualstrings?language=objc

  SFSpeechAudioBufferRecognitionRequest *recognitionRequest = [[SFSpeechAudioBufferRecognitionRequest alloc] init];
    recognitionRequest.contextualStrings = @[@"Your specific word", @"short custom phrases that are unique to your app"];

Upvotes: 3

Giuseppe Garassino
Giuseppe Garassino

Reputation: 2292

I think you cannot limit SFSpeechRecognizer's vocabulary, but you can fire action only if the words you want are recognized.

When you get your output, you can try something like this:

self.recognitionTask = speechRecognizer?.recognitionTask(with: recognitionRequest, resultHandler: { (result, error) in
    if result == "Desired word one" {
        // Do something
    } else if result == "Desired word two" {
        // Do something else
    } else {
        // Don't do anything
    }
})

Upvotes: 1

Related Questions