gecko-dev/content/media/webaudio/test/test_waveShaper.html
2013-05-14 00:12:30 -04:00

61 lines
1.7 KiB
HTML

<!DOCTYPE HTML>
<html>
<head>
<title>Test WaveShaperNode with no curve</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">
var gTest = {
length: 4096,
numberOfChannels: 1,
createGraph: function(context) {
var source = context.createBufferSource();
source.buffer = this.buffer;
var shaper = context.createWaveShaper();
shaper.curve = this.curve;
source.connect(shaper);
source.start(0);
return shaper;
},
createExpectedBuffers: function(context) {
this.buffer = context.createBuffer(1, 4096, context.sampleRate);
for (var i = 1; i < 4095; ++i) {
this.buffer.getChannelData(0)[i] = 2 * (i / 4096) - 1;
}
// Two out of range values
this.buffer.getChannelData(0)[0] = -2;
this.buffer.getChannelData(0)[4095] = 2;
this.curve = new Float32Array(2048);
for (var i = 0; i < 2048; ++i) {
this.curve[i] = Math.sin(100 * Math.PI * (i + 1) / context.sampleRate);
}
var expectedBuffer = context.createBuffer(1, 4096, context.sampleRate);
for (var i = 1; i < 4095; ++i) {
var input = this.buffer.getChannelData(0)[i];
var index = Math.floor(this.curve.length * (input + 1) / 2);
index = Math.max(0, Math.min(this.curve.length - 1, index));
expectedBuffer.getChannelData(0)[i] = this.curve[index];
}
expectedBuffer.getChannelData(0)[0] = this.curve[0];
expectedBuffer.getChannelData(0)[4095] = this.curve[2047];
return expectedBuffer;
},
};
runTest();
</script>
</pre>
</body>
</html>