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diff --git a/dom/media/webaudio/blink/HRTFKernel.h b/dom/media/webaudio/blink/HRTFKernel.h
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+++ b/dom/media/webaudio/blink/HRTFKernel.h
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+/*
+ * Copyright (C) 2010 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef HRTFKernel_h
+#define HRTFKernel_h
+
+#include "nsAutoRef.h"
+#include "nsTArray.h"
+#include "mozilla/FFTBlock.h"
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/UniquePtr.h"
+
+namespace WebCore {
+
+using mozilla::FFTBlock;
+using mozilla::UniquePtr;
+
+// HRTF stands for Head-Related Transfer Function.
+// HRTFKernel is a frequency-domain representation of an impulse-response used
+// as part of the spatialized panning system. For a given azimuth / elevation
+// angle there will be one HRTFKernel for the left ear transfer function, and
+// one for the right ear. The leading delay (average group delay) for each
+// impulse response is extracted:
+//      m_fftFrame is the frequency-domain representation of the impulse
+//                 response with the delay removed
+//      m_frameDelay is the leading delay of the original impulse response.
+class HRTFKernel {
+ public:
+  // Note: this is destructive on the passed in |impulseResponse|.
+  // The |length| of |impulseResponse| must be a power of two.
+  // The size of the DFT will be |2 * length|.
+  static nsReturnRef<HRTFKernel> create(float* impulseResponse, size_t length,
+                                        float sampleRate);
+
+  static nsReturnRef<HRTFKernel> create(UniquePtr<FFTBlock> fftFrame,
+                                        float frameDelay, float sampleRate);
+
+  // Given two HRTFKernels, and an interpolation factor x: 0 -> 1, returns an
+  // interpolated HRTFKernel.
+  static nsReturnRef<HRTFKernel> createInterpolatedKernel(HRTFKernel* kernel1,
+                                                          HRTFKernel* kernel2,
+                                                          float x);
+
+  FFTBlock* fftFrame() { return m_fftFrame.get(); }
+
+  size_t fftSize() const { return m_fftFrame->FFTSize(); }
+  float frameDelay() const { return m_frameDelay; }
+
+  float sampleRate() const { return m_sampleRate; }
+  double nyquist() const { return 0.5 * sampleRate(); }
+
+  size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
+    size_t amount = aMallocSizeOf(this);
+    amount += m_fftFrame->SizeOfIncludingThis(aMallocSizeOf);
+    return amount;
+  }
+
+ private:
+  HRTFKernel(const HRTFKernel& other) = delete;
+  void operator=(const HRTFKernel& other) = delete;
+
+  // Note: this is destructive on the passed in |impulseResponse|.
+  HRTFKernel(float* impulseResponse, size_t fftSize, float sampleRate);
+
+  HRTFKernel(UniquePtr<FFTBlock> fftFrame, float frameDelay, float sampleRate)
+      : m_fftFrame(std::move(fftFrame)),
+        m_frameDelay(frameDelay),
+        m_sampleRate(sampleRate) {}
+
+  UniquePtr<FFTBlock> m_fftFrame;
+  float m_frameDelay;
+  float m_sampleRate;
+};
+
+typedef nsTArray<nsAutoRef<HRTFKernel> > HRTFKernelList;
+
+}  // namespace WebCore
+
+template <>
+class nsAutoRefTraits<WebCore::HRTFKernel>
+    : public nsPointerRefTraits<WebCore::HRTFKernel> {
+ public:
+  static void Release(WebCore::HRTFKernel* ptr) { delete (ptr); }
+};
+
+namespace WebCore {
+
+inline nsReturnRef<HRTFKernel> HRTFKernel::create(float* impulseResponse,
+                                                  size_t length,
+                                                  float sampleRate) {
+  return nsReturnRef<HRTFKernel>(
+      new HRTFKernel(impulseResponse, length, sampleRate));
+}
+
+inline nsReturnRef<HRTFKernel> HRTFKernel::create(UniquePtr<FFTBlock> fftFrame,
+                                                  float frameDelay,
+                                                  float sampleRate) {
+  return nsReturnRef<HRTFKernel>(
+      new HRTFKernel(std::move(fftFrame), frameDelay, sampleRate));
+}
+
+}  // namespace WebCore
+
+#endif  // HRTFKernel_h