audioparam-linearRampToValueAtTime.html

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

<!DOCTYPE html>

<html>

  <head>

    <title>

      Test AudioParam.linearRampToValueAtTime

    </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>

    <script src="/webaudio/resources/audioparam-testing.js"></script>

  </head>

  <body>

    <script id="layout-test-code">

      let audit = Audit.createTaskRunner();

      // Play a long DC signal out through an AudioGainNode, and call

      // setValueAtTime() and linearRampToValueAtTime() at regular intervals to

      // set the starting and ending values for a linear ramp. Each time

      // interval has a ramp with a different starting and ending value so that

      // there is a discontinuity at each time interval boundary.  The

      // discontinuity is for testing timing.  Also, we alternate between an

      // increasing and decreasing ramp for each interval.

      // Number of tests to run.

      let numberOfTests = 100;

      // Max allowed difference between the rendered data and the expected

      // result.

      let maxAllowedError = 1.865e-6;

      // Set the gain node value to the specified value at the specified time.

      function setValue(value, time) {

        gainNode.gain.setValueAtTime(value, time);

      // Generate a linear ramp ending at time |endTime| with an ending value of

      // |value|.

      function generateRamp(value, startTime, endTime){

          // |startTime| is ignored because the linear ramp uses the value from

          // the

          // setValueAtTime() call above.

          gainNode.gain.linearRampToValueAtTime(value, endTime)}

      audit.define(

            label: 'test',

            description: 'AudioParam linearRampToValueAtTime() functionality'

},

          function(task, should) {

            createAudioGraphAndTest(

                task, should, numberOfTests, 1, setValue, generateRamp,

                'linearRampToValueAtTime()', maxAllowedError,

                createLinearRampArray);

});

      audit.run();

    </script>

  </body>

</html>