test_convolverNodeFiniteInfluence.html

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<!DOCTYPE html>

<title>Test convolution effect has finite duration</title>

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

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

<script>

promise_test(function() {

  const responseLength = 256;

  // Accept an influence period of twice the responseLength to accept FFT

  // implementations.

  const tolerancePeriod = 2 * responseLength;

  const totalSize = tolerancePeriod + responseLength;

  var context = new OfflineAudioContext(1, totalSize, 48000);

  var responseBuffer =

    context.createBuffer(1, responseLength, context.sampleRate);

  var responseChannelData = responseBuffer.getChannelData(0);

  responseChannelData[0] = 1;

  responseChannelData[responseLength - 1] = 1;

  var convolver = context.createConvolver();

  convolver.buffer = responseBuffer;

  convolver.connect(context.destination);

  var sourceBuffer = context.createBuffer(1, totalSize, context.sampleRate);

  sourceBuffer.getChannelData(0)[0] = NaN;

  var source = context.createBufferSource();

  source.buffer = sourceBuffer;

  source.connect(convolver);

  source.start();

  return context.startRendering().

    then((buffer) => {

      var convolverOutput = buffer.getChannelData(0);

      // There should be no non-zeros after the tolerance period.

      var testIndex = tolerancePeriod;

      for (;

           testIndex < buffer.length - 1 && convolverOutput[testIndex] == 0;

           ++testIndex) {

      assert_equals(convolverOutput[testIndex], 0, "output at " + testIndex);

});

});

</script>