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65 lines
1.7 KiB
HTML
65 lines
1.7 KiB
HTML
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<!DOCTYPE HTML>
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<html>
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<head>
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<title>Test repeating audio is not distorted</title>
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<script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
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<script type="text/javascript" src="webaudio.js"></script>
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<link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
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</head>
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<body>
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<pre id="test">
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<script class="testbody" type="text/javascript">
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function gcd(a, b) {
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if (b === 0) {
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return a;
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}
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return gcd(b, a % b);
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}
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var SAMPLE_PLACEMENT = 128;
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var gTest = {
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length: 2048,
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numberOfChannels: 1,
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createGraph: function(context) {
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var freq = Math.round(context.sampleRate / SAMPLE_PLACEMENT);
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var dur = context.sampleRate / gcd(freq, context.sampleRate);
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var buffer = context.createBuffer(1, dur, context.sampleRate);
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for (var i = 0; i < context.sampleRate; ++i) {
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buffer.getChannelData(0)[i] = Math.sin(freq * 2 * Math.PI * i / context.sampleRate);
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}
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var source = context.createBufferSource();
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source.buffer = buffer;
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source.loop = true;
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source.playbackRate.setValueAtTime(0.5, SAMPLE_PLACEMENT / context.sampleRate);
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source.start(0);
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return source;
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},
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createExpectedBuffers: function(context) {
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var freq = Math.round(context.sampleRate / SAMPLE_PLACEMENT);
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var expectedBuffer = context.createBuffer(1, 2048, context.sampleRate);
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var c = expectedBuffer.getChannelData(0);
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for (var i = 0; i < c.length; ++i) {
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if (i < SAMPLE_PLACEMENT) {
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c[i] = Math.sin(freq * 2 * Math.PI * i / context.sampleRate);
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} else {
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c[i] = Math.sin(freq / 2 * 2 * Math.PI * (i + SAMPLE_PLACEMENT) / context.sampleRate);
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}
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}
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return expectedBuffer;
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},
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};
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runTest();
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</script>
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</pre>
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</body>
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</html>
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