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<!DOCTYPE HTML>
<html>
<head>
  <title>Test PeriodicWave disableNormalization Parameter</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">

SimpleTest.waitForExplicitFinish();

// We create PerodicWave instances containing two tones and compare it to
// buffers created directly in JavaScript by adding the two waves together.
// Two of the PeriodicWaves are normalized, the other is not. This test is
// a modification of test_periodicWave.html.
//
// These constants are borrowed from test_periodicWave.html and modified
// so that the realPeak (which is the normalization factor) will be small
// enough that the errors are within the bounds for the test.
const realMax = 99;
var real = new Float32Array(realMax + 1);
real[1] = 2.0; // fundamental
real[realMax] = 0.25;

const realPeak = real[1] + real[realMax];
const realFundamental = 19.0;

const testLength = 4096;

addLoadEvent(function() {
  runTest();
});

var gTest = {
  createGraph: function(context) {
    var merger = context.createChannelMerger();

    var osc0 = context.createOscillator();
    var osc1 = context.createOscillator();
    var osc2 = context.createOscillator();

    osc0.setPeriodicWave(context.
                         createPeriodicWave(real,
                                            new Float32Array(real.length),
                                            {disableNormalization: false}));
    osc1.setPeriodicWave(context.
                         createPeriodicWave(real,
                                            new Float32Array(real.length)));
    osc2.setPeriodicWave(context.
                         createPeriodicWave(real,
                                            new Float32Array(real.length),
                                            {disableNormalization: true}));

    osc0.frequency.value = realFundamental;
    osc1.frequency.value = realFundamental;
    osc2.frequency.value = realFundamental;

    osc0.start();
    osc1.start();
    osc2.start();

    osc0.connect(merger, 0, 0);
    osc1.connect(merger, 0, 1);
    osc2.connect(merger, 0, 2);

    return merger;
  },
  createExpectedBuffers: function(context) {
    var buffer = context.createBuffer(3, testLength, context.sampleRate);

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

      buffer.getChannelData(0)[i] = 1.0 / realPeak *
        (real[1] * Math.cos(2 * Math.PI * realFundamental * i /
                            context.sampleRate) +
         real[realMax] * Math.cos(2 * Math.PI * realMax * realFundamental * i /
                            context.sampleRate));

      buffer.getChannelData(1)[i] = buffer.getChannelData(0)[i];

      // TODO: We need to scale by a factor of two to make the results work
      //       out here. This seems suspicious, see Bug 1266737.
      buffer.getChannelData(2)[i] = 2.0 *
        (real[1] * Math.cos(2 * Math.PI * realFundamental * i /
                            context.sampleRate) +
         real[realMax] * Math.cos(2 * Math.PI * realMax * realFundamental * i /
                            context.sampleRate));
    }
    return buffer;
  },
  'numberOfChannels': 3,
};

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