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<title>Test BiquadFilterNode</title>
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
<pre id="test">
<script src="webaudio.js" type="text/javascript"></script>
<script class="testbody" type="text/javascript">
function near(a, b, msg) {
ok(Math.abs(a - b) < 1e-3, msg);
addLoadEvent(function() {
var context = new AudioContext();
var buffer = context.createBuffer(1, 2048, context.sampleRate);
for (var i = 0; i < 2048; ++i) {
buffer.getChannelData(0)[i] = Math.sin(440 * 2 * Math.PI * i / context.sampleRate);
var destination = context.destination;
var source = context.createBufferSource();
var filter = context.createBiquadFilter();
source.buffer = buffer;
// Verify default values
is(filter.type, "lowpass", "Correct default value for type");
near(filter.frequency.defaultValue, 350, "Correct default value for filter frequency");
near(filter.detune.defaultValue, 0, "Correct default value for filter detune");
near(filter.Q.defaultValue, 1, "Correct default value for filter Q");
near(filter.gain.defaultValue, 0, "Correct default value for filter gain");
is(filter.channelCount, 2, "Biquad filter node has 2 input channels by default");
is(filter.channelCountMode, "max", "Correct channelCountMode for the biquad filter node");
is(filter.channelInterpretation, "speakers", "Correct channelCountInterpretation for the biquad filter node");
// Make sure that we can set all of the valid type values
var types = [
for (var i = 0; i < types.length; ++i) {
filter.type = types[i];
// Make sure getFrequencyResponse handles invalid frequencies properly
var frequencies = new Float32Array([-1.0, context.sampleRate*0.5 - 1.0, context.sampleRate]);
var magResults = new Float32Array(3);
var phaseResults = new Float32Array(3);
filter.getFrequencyResponse(frequencies, magResults, phaseResults);
ok(isNaN(magResults[0]), "Invalid input frequency should give NaN magnitude response");
ok(!isNaN(magResults[1]), "Valid input frequency should not give NaN magnitude response");
ok(isNaN(magResults[2]), "Invalid input frequency should give NaN magnitude response");
ok(isNaN(phaseResults[0]), "Invalid input frquency should give NaN phase response");
ok(!isNaN(phaseResults[1]), "Valid input frquency should not give NaN phase response");
ok(isNaN(phaseResults[2]), "Invalid input frquency should give NaN phase response");
SimpleTest.executeSoon(function() {