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diff --git a/testing/web-platform/tests/webaudio/the-audio-api/the-analysernode-interface/realtimeanalyser-fft-scaling.html b/testing/web-platform/tests/webaudio/the-audio-api/the-analysernode-interface/realtimeanalyser-fft-scaling.html
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+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-analysernode-interface/realtimeanalyser-fft-scaling.html
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+<!DOCTYPE html>
+<html>
+  <head>
+    <title>
+      realtimeanalyser-fft-scaling.html
+    </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>
+    <div id="description"></div>
+    <div id="console"></div>
+    <script id="layout-test-code">
+      let audit = Audit.createTaskRunner();
+
+      // The number of analysers. We have analysers from size for each of the
+      // possible sizes of 2^5 to 2^15 for a total of 11.
+      let numberOfAnalysers = 11;
+      let sampleRate = 44100;
+      let nyquistFrequency = sampleRate / 2;
+
+      // Frequency of the sine wave test signal.  Should be high enough so that
+      // we get at least one full cycle for the 32-point FFT.  This should also
+      // be such that the frequency should be exactly in one of the FFT bins for
+      // each of the possible FFT sizes.
+      let oscFrequency = nyquistFrequency / 16;
+
+      // The actual peak values from each analyser.  Useful for examining the
+      // actual peak values.
+      let peakValue = new Array(numberOfAnalysers);
+
+      // For a 0dBFS sine wave, we would expect the FFT magnitude to be 0dB as
+      // well, but the analyzer node applies a Blackman window (to smooth the
+      // estimate).  This reduces the energy of the signal so the FFT peak is
+      // less than 0dB.  The threshold value given here was determined
+      // experimentally.
+      //
+      // See https://code.google.com/p/chromium/issues/detail?id=341596.
+      let peakThreshold = [
+        -14.43, -13.56, -13.56, -13.56, -13.56, -13.56, -13.56, -13.56, -13.56,
+        -13.56, -13.56
+      ];
+
+      function checkResult(order, analyser, should) {
+        return function() {
+          let index = order - 5;
+          let fftSize = 1 << order;
+          let fftData = new Float32Array(fftSize);
+          analyser.getFloatFrequencyData(fftData);
+
+          // Compute the frequency bin that should contain the peak.
+          let expectedBin =
+              analyser.frequencyBinCount * (oscFrequency / nyquistFrequency);
+
+          // Find the actual bin by finding the bin containing the peak.
+          let actualBin = 0;
+          peakValue[index] = -1000;
+          for (k = 0; k < analyser.frequencyBinCount; ++k) {
+            if (fftData[k] > peakValue[index]) {
+              actualBin = k;
+              peakValue[index] = fftData[k];
+            }
+          }
+
+          should(actualBin, (1 << order) + '-point FFT peak position')
+              .beEqualTo(expectedBin);
+
+          should(
+              peakValue[index], (1 << order) + '-point FFT peak value in dBFS')
+              .beGreaterThanOrEqualTo(peakThreshold[index]);
+        }
+      }
+
+      audit.define(
+          {
+            label: 'FFT scaling tests',
+            description: 'Test Scaling of FFT in AnalyserNode'
+          },
+          async function(task, should) {
+            let tests = [];
+            for (let k = 5; k <= 15; ++k)
+              await runTest(k, should);
+            task.done();
+          });
+
+      function runTest(order, should) {
+        let context = new OfflineAudioContext(1, 1 << order, sampleRate);
+        // Use a sine wave oscillator as the reference source signal.
+        let osc = context.createOscillator();
+        osc.type = 'sine';
+        osc.frequency.value = oscFrequency;
+        osc.connect(context.destination);
+
+        let analyser = context.createAnalyser();
+        // No smoothing to simplify the analysis of the result.
+        analyser.smoothingTimeConstant = 0;
+        analyser.fftSize = 1 << order;
+        osc.connect(analyser);
+
+        osc.start();
+        return context.startRendering().then(() => {
+          checkResult(order, analyser, should)();
+        });
+      }
+
+      audit.run();
+    </script>
+  </body>
+</html>