How to pause android.speech.tts.TextToSpeech?

I'm playing text with android TTS - android.speech.tts.TextToSpeech

I use: TextToSpeech.speak to开发者_如何学Python speak and .stop to stop. Is there a way to pause the text also?

The TTS SDK doesn't have any pause functionality that I know of. But you could use synthesizeToFile() to create an audio file that contains the TTS output. Then, you would use a MediaPlayer object to play, pause, and stop playing the file. Depending on how long the text string is, it might take a little longer for audio to be produced because the synthesizeToFile() function would have to complete the entire file before you could play it, but this delay should be acceptable for most applications.

I used splitting of string and used playsilence() like below:

public void speakSpeech(String speech) {

    HashMap<String, String> myHash = new HashMap<String, String>();

    myHash.put(TextToSpeech.Engine.KEY_PARAM_UTTERANCE_ID, "done");

    String[] splitspeech = speech.split("\\.");

    for (int i = 0; i < splitspeech.length; i++) {

        if (i == 0) { // Use for the first splited text to flush on audio stream

            textToSpeech.speak(splitspeech[i].toString().trim(),TextToSpeech.QUEUE_FLUSH, myHash);

        } else { // add the new test on previous then play the TTS

            textToSpeech.speak(splitspeech[i].toString().trim(), TextToSpeech.QUEUE_ADD,myHash);
        }

        textToSpeech.playSilence(750, TextToSpeech.QUEUE_ADD, null);
    }
}

You can make the TTS pause between sentences, or anywhere you want by adding up to three periods (".") all followed by a single space " ". The example below has a long pause at the beginning, and again before the message body. I'm not sure that is what you are after though.

    private final BroadcastReceiver SMScatcher = new BroadcastReceiver() {

    @Override
    public void onReceive(final Context context, final Intent intent) {
        if (intent.getAction().equals(
                "android.provider.Telephony.SMS_RECEIVED")) {
            // if(message starts with SMStretcher recognize BYTE)
            StringBuilder sb = new StringBuilder();

            /*
             * The SMS-Messages are 'hiding' within the extras of the
             * Intent.
             */
            Bundle bundle = intent.getExtras();
            if (bundle != null) {
                /* Get all messages contained in the Intent */
                Object[] pdusObj = (Object[]) bundle.get("pdus");
                SmsMessage[] messages = new SmsMessage[pdusObj.length];
                for (int i = 0; i < pdusObj.length; i++) {
                    messages[i] = SmsMessage
                            .createFromPdu((byte[]) pdusObj[i]);
                }
                /* Feed the StringBuilder with all Messages found. */
                for (SmsMessage currentMessage : messages) {
                    // periods are to pause
                    sb.append("... Message From: ");
                    /* Sender-Number */
                    sb.append(currentMessage.getDisplayOriginatingAddress());
                    sb.append(".. ");
                    /* Actual Message-Content */
                    sb.append(currentMessage.getDisplayMessageBody());
                }
                // Toast.makeText(application, sb.toString(),
                // Toast.LENGTH_LONG).show();
                if (mTtsReady) {
                    try {
                        mTts.speak(sb.toString(), TextToSpeech.QUEUE_ADD,
                                null);
                    } catch (Exception e) {
                        Toast.makeText(application, "TTS Not ready",
                                Toast.LENGTH_LONG).show();
                        e.printStackTrace();
                    }
                }
            }

        }
    }
};

If you omit the space after the last period it will (or may) not work as expected.

In the absence of a pause option, you can add silence for the duration of when you want to delay the TTS Engine speaking. This of course would have to be a predetermined 'pause' and wouldn't help to include functionality of a pause button, for example.

For API < 21 : public int playSilence (long durationInMs, int queueMode, HashMap params)

For > 21 : public int playSilentUtterance (long durationInMs, int queueMode, String utteranceId)

Remember to use TextToSpeech.QUEUE_ADD rather than TextToSpeech.QUEUE_FLUSH otherwise it will clear the previously started speech.

I used a different approach.

1. Seperate your text into sentences
2. Speak every sentence one by one and keep track of the spoken sentence
3. pause will stop the text instantly
4. resume will start at the beginning of the last spoken sentence

Kotlin code:

class VoiceService {

    private lateinit var textToSpeech: TextToSpeech    

    var sentenceCounter: Int = 0
    var myList: List<String> = ArrayList()

    fun resume() {
        sentenceCounter -= 1
        speakText()
    }

    fun pause() {
        textToSpeech.stop()
    }

    fun stop() {
        sentenceCounter = 0
        textToSpeech.stop()
    }

    fun speakText() {

        var myText = "This is some text to speak. This is more text to speak."

        myList =myText.split(".")

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        textToSpeech.speak(myList[sentenceCounter], TextToSpeech.QUEUE_FLUSH, null, utteranceId)
            sentenceCounter++
        } else {
            var map: HashMap<String, String> = LinkedHashMap<String, String>()
            map[TextToSpeech.Engine.KEY_PARAM_UTTERANCE_ID] = utteranceId
            textToSpeech.speak(myList[sentenceCounter], TextToSpeech.QUEUE_FLUSH, map)
            sentenceCounter++
        }
    }

    override fun onDone(p0: String?) {
        if (sentenceCounter < myList.size) {
            speakText()
        } else {
            speakNextText()
        }
    }
}

I haven't yet tried this, but I need to do the same thing. My thinking is to first split your speech text into an array of words.

Then create a recursive function that plays the next word after the current word is finished, while keeping a counter of the current word.

divide the messages into parts and listen for last utterance by using onutteranceprogress listener

 tts.playSilence(1250, TextToSpeech.QUEUE_ADD, null);

It seems that if you put a period after a word AND start the next word with a capital letter, just like a new sentence, like this:

after we came home. We ate dinner.

the "home. We" will then have a pause in it.

• This becomes a grammatically strange way of writing it.
• So far I have only tested this in my own language, Swedish.
• It might be important that the space is there.

Also, an escaped quote (\") seems to have it pause somewhat as well - at least, if you put it around a word it adds space around the word.

This solution is not perfect, but an alternative to @Aaron C's solution may be to create a custom text to speech class like the below. This solution may work well enough if your text is relatively short and spoken words per minute is accurate enough for the language you are using.

private class CustomTextToSpeech extends TextToSpeech {
    private static final double WORDS_PER_MS = (double)190/60/1000;

    long startTimestamp = 0;
    long pauseTimestamp = 0;

    private Handler handler;
    private Runnable speakRunnable;

    StringBuilder textToSpeechBuilder;

    private boolean isPaused = false;

    public CustomTextToSpeech(Context context, OnInitListener initListener){
        super(context, initListener);

        setOnUtteranceProgressListener(new UtteranceProgressListener() {
            @Override
            public void onDone(String arg0) {
                Log.d(TAG, "tts done. " + arg0);
                startTimestamp = 0;
                pauseTimestamp = 0;
                handler.postDelayed(speakRunnable, TTS_INTERVAL_MS);
            }

            @Override
            public void onError(String arg0) {
                Log.e(TAG, "tts error. " + arg0);
            }

            @Override
            public void onStart(String arg0) {
                Log.d(TAG, "tts start. " + arg0);
                setStartTimestamp(System.currentTimeMillis());
            }
        });

        handler = new Handler();

        speakRunnable = new Runnable() {
            @Override
            public void run() {
                speak();
            }
        };

        textToSpeechBuilder = new StringBuilder(getResources().getString(R.string.talkback_tips));
    }

    public void setStartTimestamp(long timestamp) {
        startTimestamp = timestamp;
    }
    public void setPauseTimestamp(long timestamp) {
        pauseTimestamp = timestamp;
    }

    public boolean isPaused(){
        return (startTimestamp > 0 && pauseTimestamp > 0);
    }

    public void resume(){
        if(handler != null && isPaused){
            if(startTimestamp > 0 && pauseTimestamp > 0){
                handler.postDelayed(speakRunnable, TTS_SETUP_TIME_MS);
            } else {
                handler.postDelayed(speakRunnable, TTS_INTERVAL_MS);
            }
        }

        isPaused = false;
    }

    public void pause(){
        isPaused = true;

        if (handler != null) {
            handler.removeCallbacks(speakRunnable);
            handler.removeMessages(1);
        }

        if(isSpeaking()){
            setPauseTimestamp(System.currentTimeMillis());
        }

        stop();
    }

    public void utter(){
        if(handler != null){
            handler.postDelayed(speakRunnable, TTS_INTERVAL_MS);
        }
    }

    public void speak(){
        Log.d(TAG, "textToSpeechBuilder: " + textToSpeechBuilder.toString());
        if(isPaused()){
            String[] words = textToSpeechBuilder.toString().split(" ");
            int wordsAlreadySpoken = (int)Math.round((pauseTimestamp - startTimestamp)*WORDS_PER_MS);
            words = Arrays.copyOfRange(words, wordsAlreadySpoken-1, words.length);

            textToSpeechBuilder = new StringBuilder();
            for(String s : words){
                textToSpeechBuilder.append(s);
                textToSpeechBuilder.append(" ");
            }
        } else {
            textToSpeechBuilder = new StringBuilder(getResources().getString(R.string.talkback_tips));
        }

        if (tts != null && languageAvailable)
            speak(textToSpeechBuilder.toString(), TextToSpeech.QUEUE_FLUSH, new Bundle(), "utter");
    }
}