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51 lines
1.3 KiB
HTML
51 lines
1.3 KiB
HTML
<!DOCTYPE HTML>
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<html>
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<head>
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<title>Test the OscillatorNode when the frequency is negative</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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SimpleTest.waitForExplicitFinish();
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addLoadEvent(function() {
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var types = ["sine",
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"square",
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"sawtooth",
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"triangle"];
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var finished = 0;
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function finish() {
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if (++finished == types.length) {
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SimpleTest.finish();
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}
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}
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types.forEach(function(t) {
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var context = new OfflineAudioContext(1, 256, 44100);
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var osc = context.createOscillator();
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osc.frequency.value = -440;
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osc.type = t;
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osc.connect(context.destination);
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osc.start();
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context.startRendering().then(function(buffer) {
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var samples = buffer.getChannelData(0);
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// This samples the wave form in the middle of the first period, the value
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// should be negative.
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ok(samples[Math.floor(44100 / 440 / 4)] < 0., "Phase should be inverted when using a " + t + " waveform");
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finish();
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});
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});
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});
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</script>
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</pre>
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</body>
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</html>
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