1 files changed, 135 insertions, 0 deletions
diff --git a/dom/media/webaudio/blink/HRTFDatabase.cpp b/dom/media/webaudio/blink/HRTFDatabase.cpp
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+++ b/dom/media/webaudio/blink/HRTFDatabase.cpp
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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.
+ */
+
+#include "HRTFDatabase.h"
+
+#include "HRTFElevation.h"
+
+namespace WebCore {
+
+const int HRTFDatabase::MinElevation = -45;
+const int HRTFDatabase::MaxElevation = 90;
+const unsigned HRTFDatabase::RawElevationAngleSpacing = 15;
+const unsigned HRTFDatabase::NumberOfRawElevations =
+    10;  // -45 -> +90 (each 15 degrees)
+const unsigned HRTFDatabase::InterpolationFactor = 1;
+const unsigned HRTFDatabase::NumberOfTotalElevations =
+    NumberOfRawElevations * InterpolationFactor;
+
+nsReturnRef<HRTFDatabase> HRTFDatabase::create(float sampleRate) {
+  return nsReturnRef<HRTFDatabase>(new HRTFDatabase(sampleRate));
+}
+
+HRTFDatabase::HRTFDatabase(float sampleRate) : m_sampleRate(sampleRate) {
+  m_elevations.SetLength(NumberOfTotalElevations);
+
+  unsigned elevationIndex = 0;
+  for (int elevation = MinElevation; elevation <= MaxElevation;
+       elevation += RawElevationAngleSpacing) {
+    nsAutoRef<HRTFElevation> hrtfElevation(
+        HRTFElevation::createBuiltin(elevation, sampleRate));
+    MOZ_ASSERT(hrtfElevation.get());
+    if (!hrtfElevation.get()) return;
+
+    m_elevations[elevationIndex] = hrtfElevation.out();
+    elevationIndex += InterpolationFactor;
+  }
+
+  // Now, go back and interpolate elevations.
+  if (InterpolationFactor > 1) {
+    for (unsigned i = 0; i < NumberOfTotalElevations;
+         i += InterpolationFactor) {
+      unsigned j = (i + InterpolationFactor);
+      if (j >= NumberOfTotalElevations)
+        j = i;  // for last elevation interpolate with itself
+
+      // Create the interpolated convolution kernels and delays.
+      for (unsigned jj = 1; jj < InterpolationFactor; ++jj) {
+        float x =
+            static_cast<float>(jj) / static_cast<float>(InterpolationFactor);
+        m_elevations[i + jj] = HRTFElevation::createByInterpolatingSlices(
+            m_elevations[i].get(), m_elevations[j].get(), x, sampleRate);
+        MOZ_ASSERT(m_elevations[i + jj].get());
+      }
+    }
+  }
+}
+
+size_t HRTFDatabase::sizeOfIncludingThis(
+    mozilla::MallocSizeOf aMallocSizeOf) const {
+  size_t amount = aMallocSizeOf(this);
+  amount += m_elevations.ShallowSizeOfExcludingThis(aMallocSizeOf);
+  for (size_t i = 0; i < m_elevations.Length(); i++) {
+    amount += m_elevations[i]->sizeOfIncludingThis(aMallocSizeOf);
+  }
+
+  return amount;
+}
+
+void HRTFDatabase::getKernelsFromAzimuthElevation(
+    double azimuthBlend, unsigned azimuthIndex, double elevationAngle,
+    HRTFKernel*& kernelL, HRTFKernel*& kernelR, double& frameDelayL,
+    double& frameDelayR) {
+  unsigned elevationIndex = indexFromElevationAngle(elevationAngle);
+  MOZ_ASSERT(elevationIndex < m_elevations.Length() &&
+             m_elevations.Length() > 0);
+
+  if (!m_elevations.Length()) {
+    kernelL = 0;
+    kernelR = 0;
+    return;
+  }
+
+  if (elevationIndex > m_elevations.Length() - 1)
+    elevationIndex = m_elevations.Length() - 1;
+
+  HRTFElevation* hrtfElevation = m_elevations[elevationIndex].get();
+  MOZ_ASSERT(hrtfElevation);
+  if (!hrtfElevation) {
+    kernelL = 0;
+    kernelR = 0;
+    return;
+  }
+
+  hrtfElevation->getKernelsFromAzimuth(azimuthBlend, azimuthIndex, kernelL,
+                                       kernelR, frameDelayL, frameDelayR);
+}
+
+unsigned HRTFDatabase::indexFromElevationAngle(double elevationAngle) {
+  // Clamp to allowed range.
+  elevationAngle =
+      mozilla::clamped(elevationAngle, static_cast<double>(MinElevation),
+                       static_cast<double>(MaxElevation));
+
+  unsigned elevationIndex =
+      static_cast<int>(InterpolationFactor * (elevationAngle - MinElevation) /
+                       RawElevationAngleSpacing);
+  return elevationIndex;
+}
+
+}  // namespace WebCore