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<!DOCTYPE HTML>
<html>
<head>
  <title>Test AudioParam.exponentialRampToValue</title>
  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
  <script type="text/javascript" src="webaudio.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
</head>
<body>
<pre id="test">
<script class="testbody" type="text/javascript">

var V0 = 0.1;
var V1 = 0.9;
var T0 = 0;

var gTest = {
  length: 2048,
  numberOfChannels: 1,
  createGraph: function(context) {
    var sourceBuffer = context.createBuffer(1, 2048, context.sampleRate);
    for (var i = 0; i < 2048; ++i) {
      sourceBuffer.getChannelData(0)[i] = 1;
    }

    var source = context.createBufferSource();
    source.buffer = sourceBuffer;

    var gain = context.createGain();
    gain.gain.setValueAtTime(V0, 0);
    gain.gain.exponentialRampToValueAtTime(V1, 2048/context.sampleRate);

    source.connect(gain);

    source.start(0);
    return gain;
  },
  createExpectedBuffers: function(context) {
    var T1 = 2048 / context.sampleRate;
    var expectedBuffer = context.createBuffer(1, 2048, context.sampleRate);
    for (var i = 0; i < 2048; ++i) {
      var t = i / context.sampleRate;
      expectedBuffer.getChannelData(0)[i] = V0 * Math.pow(V1 / V0, (t - T0) / (T1 - T0));
    }
    return expectedBuffer;
  },
};

runTest();

</script>
</pre>
</body>
</html>