Chrome語音合成api沒有改變選項

Question

我正在嘗試更改語音合成API的選項（例如音高，音量等）的實例，但它不起作用。 出於某種原因，我可以讓它改變從英國男性到英國女性的聲音的唯一方法是將var voices變量調用兩次，但這是我可以改變的唯一選擇。 這是代碼：

//After the document loads (using the prototype library)
document.observe("dom:loaded", function() {
    //When the speakMe button is clicked
    $("speakMe").observe('click', function() {
        //Get the entered phrase
        phrase = $('phraseBar').getValue();
        //If the phrase is blank
        if(phrase =="")
        {
            //Warning message
            alert("Please enter a phrase before asking me to speak for you. Thank you!");
        }
        else
        {
            //Declare the speach object & set attributes
            var speech = new SpeechSynthesisUtterance(phrase);
            var voices = speechSynthesis.getVoices();
            var options = new Object();
            speech.default = false;
            speech.localservice = true;
            speech.voice = voices.filter(function(voice) { return voice.name == userVoice; })[0];    
            speech.lang = userLang;
            speech.rate = userRate;
            speech.pitch = 2;
            speech.volume = userVolume;

            //Speak the phrase
            window.speechSynthesis.speak(speech);

        }
    });
    var voices = speechSynthesis.getVoices();
});

有任何想法嗎？

Answer 1

有一個Chrome已知的問題 ，速率，音量或音高選項對某些聲音沒有影響。

另外， speechSynthesis.getVoices()第二次運行的原因是它在Chrome中它應該在onvoiceschanged事件之后被調用（參見這個答案 ）。