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Is the Web Audio source.start (0) API supported in Safari (it works fine in Chrome)?

I am trying to implement a web audio API. The code works on Chrome 29.0.1547.76, but not on Safari 6.0.5 (8536.30.1). The key is whether I use noteOn (0) or start (0).

I want to use start () to play part of the sound:

asource.start(0, 2, 1);

works great in Chrome (plays immediately, starts at 2 s, plays for 1 s), but leads to

TypeError: 'undefined' is not a function (evaluating 'asource.start(0, 2, 1)')

in Safari. Replacing this single line with

asource.noteOn(0);

working. [Well, I need to call noteOff (0) instead of stop (0).] I get the same error with start (0). So, I assume that Safari does not implement start (0)? But if so, why do some HTML5 Rocks examples that use start (0) work?

, -. /; .

<!DOCTYPE html>
<html lang=en>
<head>
<meta charset="utf-8">
<title>Web Audio API Issue</title>
</head>
<body>
<p>Example working on Chrome but not Safari when using start()</p>

<button id="Load" onclick="init()" >Load</button>
<button id="Play" onclick="playSound()" disabled>Play</button>
<button id="Stop" onclick="stopSound()" disabled>Stop</button>

<script>
    var web_audio_context;
    var abuffer;
    var asource;

    function init() {
        contextClass = (window.AudioContext || 
            window.webkitAudioContext || 
            window.mozAudioContext || 
            window.msAudioContext);
        web_audio_context = new contextClass();

        var theURL = './digits.mp3';
        var xhr = new XMLHttpRequest();
        xhr.open('GET', theURL, true);
        xhr.responseType = 'arraybuffer';
        xhr.onload = function(e) {
            finishedLoading(this.response);
        };
        xhr.send();
    }

    function finishedLoading(arrayBuffer) {
        web_audio_context.decodeAudioData(arrayBuffer, function(buffer) {
            abuffer = buffer;
            document.getElementById('Load').disabled = true;
            document.getElementById('Play').disabled = false;
            document.getElementById('Stop').disabled = false;
        }, function(e) {
            console.log('Error decoding file', e);
        }); 
    }

    function playSound() {
        asource = web_audio_context.createBufferSource();
        asource.buffer = abuffer;
        asource.connect(web_audio_context.destination);
        asource.start(0, 2, 1);

    }

    function stopSound() {
        asource.stop(0);
    }
</script>
</body>
</html>
+4
2

API Web Audio noteOn start. Safari - , Chrome .

:

asource.start ? asource.start(0, 2, 1) : asource.noteOn(0, 2, 1);
+4

- API . .

+2

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