test-analyser-scale.html

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

<!DOCTYPE html>

<html>

<head>

  <meta charset="utf-8">

  <title>Test AnalyserNode when the input is scaled</title>

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

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

  <script>

    setup({ single_test: true });

    var context = new AudioContext();

    var gain = context.createGain();

    var analyser = context.createAnalyser();

    var osc = context.createOscillator();

    osc.connect(gain);

    gain.connect(analyser);

    osc.start();

    var array = new Uint8Array(analyser.frequencyBinCount);

    function getAnalyserData() {

      gain.gain.setValueAtTime(currentGain, context.currentTime);

      analyser.getByteTimeDomainData(array);

      var inrange = true;

      var max = -1;

      for (var i = 0; i < array.length; i++) {

        if (array[i] > max) {

          max = Math.abs(array[i] - 128);

      if (max <= currentGain * 128) {

        assert_true(true, "Analyser got scaled data for " + currentGain);

        currentGain = tests.shift();

        if (currentGain == undefined) {

          done();

          return;

      requestAnimationFrame(getAnalyserData);

    var tests = [1.0, 0.5, 0.0];

    var currentGain = tests.shift();

    requestAnimationFrame(getAnalyserData);

  </script>

</head>

</body>

</html>