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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<script src="resources/audio-testing.js"></script>
<script src="resources/audioparam-testing.js"></script>
<script src="../resources/js-test-pre.js"></script>
<div id="description"></div>
<div id="console"></div>
description("Test AudioParam setValueCurveAtTime() functionality.");
// Play a long DC signal out through an AudioGainNode and for each time interval call
// setValueCurveAtTime() to set the values for the duration of the interval. Each curve is a sine
// wave, and we assume that the time interval is not an exact multiple of the period. This causes a
// discontinuity between time intervals which is used to test timing.
// Number of tests to run.
var numberOfTests = 20;
// Max allowed difference between the rendered data and the expected result. (The error is zero
// because the rendered curve should really be exactly the same as the reference.)
var maxAllowedError = 0;
// The amplitude of the sine wave.
var sineAmplitude = 1;
// Frequency of the sine wave.
var freqHz = 440;
// Curve to use for setValueCurveAtTime().
var curve;
// Sets the curve data for the entire time interval.
function automation(value, startTime, endTime)
gainNode.gain.setValueCurveAtTime(curve, startTime, endTime - startTime);
// Create a sine wave of the specified duration.
function createReferenceSineArray(startTime, endTime, startValue, endValue, sampleRate)
// Ignore |startValue| and |endValue| for the sine wave.
return createSineWaveArray(endTime - startTime, freqHz, sineAmplitude, sampleRate);
function runTest()
// The curve of values to use.
curve = createSineWaveArray(timeInterval, freqHz, sineAmplitude, sampleRate);
function(k) {
// Don't need to set the value.
2 * Math.PI * sineAmplitude * freqHz / sampleRate);
successfullyParsed = true;
<script src="../resources/js-test-post.js"></script>
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