mediastreamaudiosourcenode-routing.html

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This WPT test may be referenced by the following Test IDs:
- /webaudio/the-audio-api/the-mediastreamaudiosourcenode-interface/mediastreamaudiosourcenode-routing.html - WPT Dashboard Interop Dashboard

<!DOCTYPE html>

<html class="a">

  <head>

    <title>MediaStreamAudioSourceNode</title>

    <script src="/resources/testharness.js"></script>

    <script src="/resources/testharnessreport.js"></script>

  </head>

  <body class="a">

    <div id="log"></div>

    <script>

      function binIndexForFrequency(frequency, analyser) {

        return (

1 +

          Math.round(

            (frequency * analyser.fftSize) / analyser.context.sampleRate

);

      const t = async_test(

        "MediaStreamAudioSourceNode captures the right track."

);

      t.step(function() {

          const ac = new AudioContext();

          // Test that the right track is captured. Set up a MediaStream that has two

          // tracks, one with a tone at 100Hz and one with a tone at 1000Hz.

          const dest0 = ac.createMediaStreamDestination();

          const dest1 = ac.createMediaStreamDestination();

          const osc0 = ac.createOscillator();

          const osc1 = ac.createOscillator();

          osc0.frequency.value = 100;

          osc1.frequency.value = 1000;

          osc0.connect(dest0);

          osc1.connect(dest1);

          osc0.start(0);

          osc1.start(0);

          const track0 = dest0.stream.getAudioTracks()[0];

          const track0id = track0.id;

          const track1 = dest1.stream.getAudioTracks()[0];

          const track1id = track1.id;

          let ids = [track0id, track1id];

          ids.sort();

          let targetFrequency;

          let otherFrequency;

          if (ids[0] == track0id) {

              targetFrequency = 100;

              otherFrequency = 1000;

          } else {

              targetFrequency = 1000;

              otherFrequency = 100;

          let twoTrackMediaStream = new MediaStream();

          twoTrackMediaStream.addTrack(track0);

          twoTrackMediaStream.addTrack(track1);

          const twoTrackSource = ac.createMediaStreamSource(twoTrackMediaStream);

          const analyser = ac.createAnalyser();

          // Don't do smoothing so that the frequency data changes quickly

          analyser.smoothingTimeConstant = 0;

          twoTrackSource.connect(analyser);

          const indexToCheckForHighEnergy = binIndexForFrequency(

              targetFrequency,

              analyser

);

          const indexToCheckForLowEnergy = binIndexForFrequency(

              otherFrequency,

              analyser

);

          let frequencyData = new Float32Array(1024);

          let checkCount = 0;

          let numberOfRemovals = 0;

          let stopped = false;

          function analyse() {

              analyser.getFloatFrequencyData(frequencyData);

              // there should be high energy in the right bin, higher than 40dbfs because

              // it's supposed to be a sine wave at 0dbfs

              if (frequencyData[indexToCheckForHighEnergy] > -40 && !stopped) {

                  assert_true(true, "Correct track routed to the AudioContext.");

                  checkCount++;

              if (stopped && frequencyData[indexToCheckForHighEnergy] < -40) {

                  assert_true(

                      true,

                      `After stopping the track, low energy is found in the

              same bin`

);

                  checkCount++;

              if (checkCount > 5 && checkCount < 20) {

                  twoTrackMediaStream.getAudioTracks().forEach(track => {

                      if (track.id == ids[0]) {

                          numberOfRemovals++;

                          window.removedTrack = track;

                          twoTrackMediaStream.removeTrack(track);

});

                  assert_true(

                      numberOfRemovals == 1,

                      `The mediastreamtrack can only be

        removed once from the mediastream`

);

              } else if (checkCount >= 20 && checkCount < 30) {

                  window.removedTrack.stop();

                  stopped = true;

              } else if (checkCount >= 30) {

                  assert_true(

                      numberOfRemovals == 1,

                      `After removing the track from the

        mediastream, it's still routed to the graph.`

);

                  // After some time, consider that it worked.

                  t.done();

                  return;

              t.step_timeout(analyse, 100);

          t.step_timeout(analyse, 100);

});

    </script>

  </body>

</html>