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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>
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