问ScriptProcessorNode跳过

EN

var audio = null;

try {
    window.AudioContext = window.AudioContext ||     window.webkitAudioContext;
    audio = new AudioContext();
} catch (e) {
    alert("Web Audio API is not supported in this browser");
}

var INTERVAL = 4;  // 4 [sec]

var scriptNode = audio.createScriptProcessor(1024, 0, 1);

var pos = 0.0;

var elapsedBuffer = 0;

scriptNode.onaudioprocess = function(audioProcessingEvent) {
    var output = audioProcessingEvent.outputBuffer;

    for (var channel = 0; channel < output.numberOfChannels; channel++) {
        var data = output.getChannelData(channel);

        for (var i = 0; i < data.length; i++) {
            elapsedBuffer++;

            if (elapsedBuffer > audio.sampleRate) {
                if (elapsedBuffer > (INTERVAL * audio.sampleRate)) {
                    elapsedBuffer = 0;
                }

                data[i] = 0;

                continue;
            }

            data[i] = Math.sin(pos);

            pos += 2.0 * 3.14159 * 440.0 / audio.sampleRate;

            while (pos >= 2.0 * 3.14159) {
                pos -= 2.0 * 3.14159;
            }
        }
    }
};

scriptNode.connect(audio.destination);