timeline-insert-event.html | Explore in Territory

<!DOCTYPE html>
<html>
  <head>
    <title>
      Test performance of AudioParamTimeline::InsertEvent.
    </title>
    <script src="../resources/runner.js"></script>
  </head>
  <body>
    <script>
      // Number of events to insert.
      let numberOfEvents = 10000;
      let sampleRate = 44100;
      let gainNode = null;
      let timeInterval = .03;
      let initialValue = 1;
      let startingValueDelta = initialValue / numberOfEvents;

      // Convert time (in seconds) to sample frames.
      function timeToSampleFrame(time, sampleRate) {
        return Math.floor(0.5 + time * sampleRate);
      }

      function renderLength(numberOfEvents) {
        return timeToSampleFrame((numberOfEvents + 1) * timeInterval, sampleRate);
      }

      PerfTestRunner.measureTime({
        description: "Measures performance of 10k InsertEvents using calls to setValueAtTime.",

        setup: function () {
          let context =
                new OfflineAudioContext(2, renderLength(numberOfEvents), sampleRate);
          gainNode = context.createGain();
        },

        run: function() {
          let value = initialValue;
          for (let k = 0; k < numberOfEvents; ++k) {
            let startTime = k * timeInterval;
            gainNode.gain.setValueAtTime(value, startTime);
            value -= startingValueDelta;
          }
        },
        iterationCount: 5,
        warmUpCount: 2,
        tracingCategories: 'disabled-by-default-webaudio.audionode',
        traceEventsToMeasure: ['AudioParamTimeline::InsertEvent'],
      });
    </script>
  </body>
</html>
chromium/third_party/blink/perf_tests/webaudio/timeline-insert-event.html
