audiobuffersource-grain.html

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

<!DOCTYPE html>

<html>

  <head>

    <title>

      Test Start Grain with Delayed Buffer Setting

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

      let audit = Audit.createTaskRunner();

      let context;

      let source;

      let buffer;

      let renderedData;

      let sampleRate = 44100;

      let testDurationSec = 1;

      let testDurationSamples = testDurationSec * sampleRate;

      let startTime = 0.9 * testDurationSec;

      audit.define(

          'Test setting the source buffer after starting the grain',

          function(task, should) {

            context =

                new OfflineAudioContext(1, testDurationSamples, sampleRate);

            buffer = createConstantBuffer(context, testDurationSamples, 1);

            source = context.createBufferSource();

            source.connect(context.destination);

            // Start the source BEFORE we set the buffer. The grain offset and

            // duration aren't important, as long as we specify some offset.

            source.start(startTime, .1);

            source.buffer = buffer;

            // Render it!

            context.startRendering()

                .then(function(buffer) {

                  checkResult(buffer, should);

})

                .then(task.done.bind(task));

});

      function checkResult(buffer, should) {

        let success = false;

        renderedData = buffer.getChannelData(0);

        // Check that the rendered data is not all zeroes.  Any non-zero data

        // means the test passed.

        let startFrame = Math.round(startTime * sampleRate);

        for (k = 0; k < renderedData.length; ++k) {

          if (renderedData[k]) {

            success = true;

            break;

        should(success, 'Buffer was played').beTrue();

      audit.run();

    </script>

  </body>

</html>