k-rate-oscillator.html

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This test has a WPT meta file that expects 5 subtest issues.
This WPT test may be referenced by the following Test IDs:
- /webaudio/the-audio-api/the-audioparam-interface/k-rate-oscillator.html - WPT Dashboard Interop Dashboard

<!doctype html>

<html>

  <head>

    <title>Test k-rate AudioParams of OscillatorNode</title>

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

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

    <script src="/webaudio/resources/audit-util.js"></script>

    <script src="/webaudio/resources/audit.js"></script>

  </head>

  <body>

    <script>

      let audit = Audit.createTaskRunner();

      // Arbitrary sample rate and duration.

      let sampleRate = 8000;

      // Only new a few render quanta to verify things are working.

      let testDuration = 4 * 128 / sampleRate;

      [{name: 'detune', initial: 0, final: 1200}, {

        name: 'frequency',

        initial: 440,

        final: sampleRate / 2

      }].forEach(paramProperty => {

        audit.define(

            'Oscillator k-rate ' + paramProperty.name, (task, should) => {

              let context = new OfflineAudioContext({

                numberOfChannels: 3,

                sampleRate: sampleRate,

                length: testDuration * sampleRate

});

              let merger = new ChannelMergerNode(

                  context, {numberOfInputs: context.destination.channelCount});

              merger.connect(context.destination);

              let inverter = new GainNode(context, {gain: -1});

              inverter.connect(merger, 0, 2);

              let kRateNode = new OscillatorNode(context);

              let aRateNode = new OscillatorNode(context);

              kRateNode.connect(merger, 0, 0);

              aRateNode.connect(merger, 0, 1);

              kRateNode.connect(merger, 0, 2);

              aRateNode.connect(inverter);

              // Set the rate

              kRateNode[paramProperty.name].automationRate = 'k-rate';

              // Automate the offset

              kRateNode[paramProperty.name].setValueAtTime(

                  paramProperty.initial, 0);

              kRateNode[paramProperty.name].linearRampToValueAtTime(

                  paramProperty.final, testDuration);

              aRateNode[paramProperty.name].setValueAtTime(

                  paramProperty.initial, 0);

              aRateNode[paramProperty.name].linearRampToValueAtTime(

                  paramProperty.final, testDuration);

              kRateNode.start();

              aRateNode.start();

              context.startRendering()

                  .then(audioBuffer => {

                    let kRateOut = audioBuffer.getChannelData(0);

                    let aRateOut = audioBuffer.getChannelData(1);

                    let diff = audioBuffer.getChannelData(2);

                    // Verify that the outputs are different.

                    should(

                        diff,

                        'k-rate ' + paramProperty.name +

                            ': Difference between a-rate and k-rate outputs')

                        .notBeConstantValueOf(0);

})

                  .then(() => task.done());

});

});

      audit.run();

    </script>

  </body>

</html>