test_setSinkId-echoCancellation.html

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<!DOCTYPE HTML>

<html>

<head>

<title></title>

<script src="mediaStreamPlayback.js"></script>

</head>

<script>

"use strict";

createHTML({

  title: "Test echoCancellation with setSinkId()",

  bug: "1849108",

  visible: true,

});

/**

This test captures audio from a loopback device to test echo cancellation.

**/

runTest(async () => {

  await SpecialPowers.pushPrefEnv({set: [

    // skip selectAudioOutput/getUserMedia permission prompt

    ["media.navigator.permission.disabled", true],

    // enumerateDevices() without focus

    ["media.devices.unfocused.enabled", true],

  ]});

  const ac = new AudioContext();

  const dest = new MediaStreamAudioDestinationNode(ac);

  const gain = new GainNode(ac, {gain: 0.5});

  gain.connect(dest);

  // Use a couple of triangle waves for audio with some bandwidth.

  // Pick incommensurable frequencies so that the audio is aperiodic.

  // Perhaps that might help the AEC determine the delay.

  const osc1 =

        new OscillatorNode(ac, {type: "triangle", frequency: 200});

  const osc2 =

        new OscillatorNode(ac, {type: "triangle", frequency: Math.PI * 100});

  osc1.connect(gain);

  osc2.connect(gain);

  osc1.start();

  osc2.start();

  const audio = new Audio();

  audio.srcObject = dest.stream;

  audio.controls = true;

  document.body.appendChild(audio);

  // The loopback device is currenly only available on Linux.

  let loopbackInputLabel =

      SpecialPowers.getCharPref("media.audio_loopback_dev", "");

  if (!navigator.userAgent.includes("Linux")) {

    todo_isnot(loopbackInputLabel, "", "audio_loopback_dev");

    return;

  isnot(loopbackInputLabel, "",

        "audio_loopback_dev. Use --use-test-media-devices.");

  const loopbackStream = await navigator.mediaDevices.getUserMedia({ audio: {

    echoCancellation: false,

    autoGainControl: false,

    noiseSuppression: false,

  }});

  is(loopbackStream.getTracks()[0].label, loopbackInputLabel,

     "loopback track label");

  // Check that the loopback stream contains silence now.

  const loopbackNode = ac.createMediaStreamSource(loopbackStream);

  const processor1 = ac.createScriptProcessor(4096, 1, 0);

  loopbackNode.connect(processor1);

  const {inputBuffer} = await new Promise(r => processor1.onaudioprocess = r);

  loopbackNode.disconnect();

  is(inputBuffer.getChannelData(0).find(value => value != 0.0), undefined,

     "should have silence in loopback input");

  // Find the loopback output device

  const devices = await navigator.mediaDevices.enumerateDevices();

  let loopbackOutputLabel =

      SpecialPowers.getCharPref("media.cubeb.output_device", "");

  const outputDeviceInfo = devices.find(

    ({kind, label}) => kind == "audiooutput" && label == loopbackOutputLabel

);

  ok(outputDeviceInfo, `found "${loopbackOutputLabel}"`);

  await audio.setSinkId(outputDeviceInfo.deviceId);

  await audio.play();

  const analyser = new AudioStreamAnalyser(ac, loopbackStream);

  const bin1 = analyser.binIndexForFrequency(osc1.frequency.value);

  const bin2 = analyser.binIndexForFrequency(osc2.frequency.value);

  try {

    analyser.enableDebugCanvas();

    // Check for audio with AEC.

    await analyser.waitForAnalysisSuccess(array => {

      return array[bin1] > 200 && array[bin2] > 200;

});

    // Check echo cancellation.

    await loopbackStream.getTracks()[0].applyConstraints({

      echoCancellation: true,

      autoGainControl: false,

      noiseSuppression: false,

});

    await analyser.waitForAnalysisSuccess(array => {

      return !array.find(bin => bin > 50);

});

  } finally {

    await ac.close();

    loopbackStream.getTracks()[0].stop();

});

</script>

</html>