firefox-main/testing/web-platform/tests/webaudio/the-audio-api/the-mediaelementaudiosourcenode-interface/mediaElementAudioSource_volumeChange.html

Source code

Revision control

Copy as Markdown

Other Tools

Test Info:

  • This WPT test may be referenced by the following Test IDs:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>MediaElementAudioSourceNode reflects HTMLMediaElement effective volume changes</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="../../resources/rms-utils.js"></script>
</head>
<body>
<audio loop controls></audio>
<script>
// Verify that MediaElementAudioSourceNode output reflects changes in
// HTMLMediaElement effective volume (including the muted attribute) by
// observing via WebAudio API.
const testLabel =
`createMediaElementSource() output reflects HTMLMediaElement effective `+
`volume changes (volume/muted)`;
// Test media element with src
promise_test(async t => {
const audio = document.querySelector("audio");
audio.src = "/media/sine440.mp3";
audio.onerror = t.unreached_func("audio error");
const ac = new AudioContext();
t.add_cleanup(() => {
ac.close()
audio.src = "";
audio.removeAttribute("src");
});
await testSourceVolumeChangeForMediaElementAudioSourceNode(audio, ac);
}, testLabel + "(src-file)");
// Test media element with srcObj
promise_test(async t => {
const ac = new AudioContext();
const dest = ac.createMediaStreamDestination();
const osc = ac.createOscillator();
osc.frequency.value = 440;
osc.connect(dest);
osc.start();
const audio = document.querySelector("audio");
audio.srcObject = dest.stream;
audio.onerror = t.unreached_func("audio error");
t.add_cleanup(() => {
ac.close()
audio.srcObject = null;
});
await testSourceVolumeChangeForMediaElementAudioSourceNode(audio, ac);
}, testLabel + "(src-stream)");
// Helper functions
async function testSourceVolumeChangeForMediaElementAudioSourceNode(audio, ac) {
const src = ac.createMediaElementSource(audio);
await test_driver.bless("start playback + resume AudioContext", async () => {
await ac.resume();
await audio.play();
});
// Expected audible from the graph.
let tempAudibleThreshold = 0.01; // temporary threshold to consider the input audible
let fullRms = await RMSUtils.waitForRmsOverThreshold(ac, src, tempAudibleThreshold);
assert_greater_than(fullRms, tempAudibleThreshold, `Expected audible baseline RMS ${fullRms}`);
// Heuristic, baseline-relative thresholds to avoid flakiness (not exact gain checks).
const AUDIBLE_RMS_THRESHOLD = fullRms * 0.7;
const SILENCE_RMS_THRESHOLD = 0;
// Lower the media element's volume.
audio.volume = 0.0;
let curRms = await RMSUtils.waitForRmsEqualToThreshold(ac, src, SILENCE_RMS_THRESHOLD);
assert_equals(
curRms, SILENCE_RMS_THRESHOLD,
"Expected exact silence after volume=0"
);
// Test a volume which is not zero and 1.0.
audio.volume = 0.3;
tempAudibleThreshold = AUDIBLE_RMS_THRESHOLD * audio.volume;
curRms = await RMSUtils.waitForRmsOverThreshold(ac, src, tempAudibleThreshold);
assert_greater_than(
curRms, tempAudibleThreshold,
`Expected non-silent RMS ${curRms} after volume=0.3`
);
// Increase volume back to 1.0.
audio.volume = 1.0;
curRms = await RMSUtils.waitForRmsOverThreshold(ac, src, AUDIBLE_RMS_THRESHOLD);
assert_greater_than(
curRms, AUDIBLE_RMS_THRESHOLD,
`Expected RMS ${curRms} to recover after volume=1`
);
// Mute the media element.
audio.muted = true;
curRms = await RMSUtils.waitForRmsEqualToThreshold(ac, src, SILENCE_RMS_THRESHOLD);
assert_equals(
curRms, SILENCE_RMS_THRESHOLD,
"Expected exact silence after muted"
);
// Unmute the media element.
audio.muted = false;
curRms = await RMSUtils.waitForRmsOverThreshold(ac, src, AUDIBLE_RMS_THRESHOLD);
assert_greater_than(
curRms, AUDIBLE_RMS_THRESHOLD,
`Expected RMS ${curRms} to recover after unmuted`
);
}
</script>
</body>
</html>