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Test Info:

<!DOCTYPE HTML>
<html>
<head>
<title>Test repeating audio is not distorted</title>
<script 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">
function gcd(a, b) {
if (b === 0) {
return a;
}
return gcd(b, a % b);
}
var SAMPLE_PLACEMENT = 128;
var gTest = {
length: 2048,
numberOfChannels: 1,
createGraph(context) {
var freq = Math.round(context.sampleRate / SAMPLE_PLACEMENT);
var dur = context.sampleRate / gcd(freq, context.sampleRate);
var buffer = context.createBuffer(1, dur, context.sampleRate);
for (var i = 0; i < context.sampleRate; ++i) {
buffer.getChannelData(0)[i] = Math.sin(freq * 2 * Math.PI * i / context.sampleRate);
}
var source = context.createBufferSource();
source.buffer = buffer;
source.loop = true;
source.playbackRate.setValueAtTime(0.5, SAMPLE_PLACEMENT / context.sampleRate);
source.start(0);
return source;
},
createExpectedBuffers(context) {
var freq = Math.round(context.sampleRate / SAMPLE_PLACEMENT);
var expectedBuffer = context.createBuffer(1, 2048, context.sampleRate);
var c = expectedBuffer.getChannelData(0);
for (var i = 0; i < c.length; ++i) {
if (i < SAMPLE_PLACEMENT) {
c[i] = Math.sin(freq * 2 * Math.PI * i / context.sampleRate);
} else {
c[i] = Math.sin(freq / 2 * 2 * Math.PI * (i + SAMPLE_PLACEMENT) / context.sampleRate);
}
}
return expectedBuffer;
},
};
runTest();
</script>
</pre>
</body>
</html>