Speech to Text on Android

RenegadeAndy picture RenegadeAndy · May 6, 2011 · Viewed 36.6k times · Source

I am looking to create an app which has Speech to text.

I am aware of this kind of ability using the RecognizerIntent: http://android-developers.blogspot.com/search/label/Speech%20Input

However - I do not want a new Intent to be popped up, I want to do the analysis a certain points in my current app, and I dont want it to pop something up stating that it is currently attempting to record your voice.

Has anybody any ideas on how best to do this. I was perhaps thinking of trying Sphinx 4 - but I dont know if this would be able to run on Android - has anyone got any advice or experience?!

I was wondering if I could alter the code here to perhaps not bothering to show the UI or button and just do the processing: http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/app/VoiceRecognition.html

Cheers,

Answer

Stephan picture Stephan · May 6, 2011

If you don't want to use the RecognizerIntent to do speech recognition, you could still use the SpeechRecognizer class to do it. However, using that class is a little bit more tricky than using the intent. As a final note, I would highly suggest to let the user know when he is recorded, otherwise he might be very set up, when he finally finds out.

Edit: A small example inspired (but changed) from, SpeechRecognizer causes ANR... I need help with Android speech API

Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
        RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_CALLING_PACKAGE,
        "com.domain.app");

SpeechRecognizer recognizer = SpeechRecognizer
        .createSpeechRecognizer(this.getApplicationContext());
RecognitionListener listener = new RecognitionListener() {
    @Override
    public void onResults(Bundle results) {
        ArrayList<String> voiceResults = results
                .getStringArrayList(SpeechRecognizer.RESULTS_RECOGNITION);
        if (voiceResults == null) {
            System.out.println("No voice results");
        } else {
            System.out.println("Printing matches: ");
            for (String match : voiceResults) {
                System.out.println(match);
            }
        }
    }

    @Override
    public void onReadyForSpeech(Bundle params) {
        System.out.println("Ready for speech");
    }

    /**
     *  ERROR_NETWORK_TIMEOUT = 1;
     *  ERROR_NETWORK = 2;
     *  ERROR_AUDIO = 3;
     *  ERROR_SERVER = 4;
     *  ERROR_CLIENT = 5;
     *  ERROR_SPEECH_TIMEOUT = 6;
     *  ERROR_NO_MATCH = 7;
     *  ERROR_RECOGNIZER_BUSY = 8;
     *  ERROR_INSUFFICIENT_PERMISSIONS = 9;
     *
     * @param error code is defined in SpeechRecognizer
     */
    @Override
    public void onError(int error) {
        System.err.println("Error listening for speech: " + error);
    }

    @Override
    public void onBeginningOfSpeech() {
        System.out.println("Speech starting");
    }

    @Override
    public void onBufferReceived(byte[] buffer) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onEndOfSpeech() {
        // TODO Auto-generated method stub

    }

    @Override
    public void onEvent(int eventType, Bundle params) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onPartialResults(Bundle partialResults) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onRmsChanged(float rmsdB) {
        // TODO Auto-generated method stub

    }
};
recognizer.setRecognitionListener(listener);
recognizer.startListening(intent);

Important: Run this code from the UI Thread, and make sure you have required permissions.

<uses-permission android:name="android.permission.RECORD_AUDIO" />