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diff --git a/dom/media/webaudio/blink/PeriodicWave.h b/dom/media/webaudio/blink/PeriodicWave.h
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+/*
+ * Copyright (C) 2012 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 PeriodicWave_h
+#define PeriodicWave_h
+
+#include "mozilla/dom/OscillatorNodeBinding.h"
+#include <nsAutoPtr.h>
+#include <nsTArray.h>
+#include "AlignedTArray.h"
+#include "mozilla/MemoryReporting.h"
+
+namespace WebCore {
+
+typedef AlignedTArray<float> AlignedAudioFloatArray;
+typedef nsTArray<float> AudioFloatArray;
+
+class PeriodicWave {
+public:
+    NS_INLINE_DECL_THREADSAFE_REFCOUNTING(WebCore::PeriodicWave);
+
+    static already_AddRefed<PeriodicWave> createSine(float sampleRate);
+    static already_AddRefed<PeriodicWave> createSquare(float sampleRate);
+    static already_AddRefed<PeriodicWave> createSawtooth(float sampleRate);
+    static already_AddRefed<PeriodicWave> createTriangle(float sampleRate);
+
+    // Creates an arbitrary periodic wave given the frequency components
+    // (Fourier coefficients).
+    static already_AddRefed<PeriodicWave> create(float sampleRate,
+                                                 const float* real,
+                                                 const float* imag,
+                                                 size_t numberOfComponents,
+                                                 bool disableNormalization);
+
+    // Returns pointers to the lower and higher wave data for the pitch range
+    // containing the given fundamental frequency. These two tables are in
+    // adjacent "pitch" ranges where the higher table will have the maximum
+    // number of partials which won't alias when played back at this
+    // fundamental frequency. The lower wave is the next range containing fewer
+    // partials than the higher wave. Interpolation between these two tables
+    // can be made according to tableInterpolationFactor. Where values
+    // from 0 -> 1 interpolate between lower -> higher.
+    void waveDataForFundamentalFrequency(float, float* &lowerWaveData, float* &higherWaveData, float& tableInterpolationFactor);
+
+    // Returns the scalar multiplier to the oscillator frequency to calculate
+    // wave buffer phase increment.
+    float rateScale() const { return m_rateScale; }
+
+    unsigned periodicWaveSize() const { return m_periodicWaveSize; }
+    float sampleRate() const { return m_sampleRate; }
+
+    size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
+
+private:
+    explicit PeriodicWave(float sampleRate, size_t numberOfComponents, bool disableNormalization);
+    ~PeriodicWave() {}
+
+    void generateBasicWaveform(mozilla::dom::OscillatorType);
+
+    float m_sampleRate;
+    unsigned m_periodicWaveSize;
+    unsigned m_numberOfRanges;
+    float m_centsPerRange;
+    unsigned m_numberOfComponents;
+    nsAutoPtr<AudioFloatArray> m_realComponents;
+    nsAutoPtr<AudioFloatArray> m_imagComponents;
+
+    // The lowest frequency (in Hertz) where playback will include all of the
+    // partials.  Playing back lower than this frequency will gradually lose
+    // more high-frequency information.
+    // This frequency is quite low (~10Hz @ // 44.1KHz)
+    float m_lowestFundamentalFrequency;
+
+    float m_rateScale;
+
+    unsigned numberOfRanges() const { return m_numberOfRanges; }
+
+    // Maximum possible number of partials (before culling).
+    unsigned maxNumberOfPartials() const;
+
+    unsigned numberOfPartialsForRange(unsigned rangeIndex) const;
+
+    // Creates table for specified index based on fundamental frequency.
+    void createBandLimitedTables(float fundamentalFrequency, unsigned rangeIndex);
+    unsigned m_maxPartialsInBandLimitedTable;
+    float m_normalizationScale;
+    bool m_disableNormalization;
+    nsTArray<nsAutoPtr<AlignedAudioFloatArray> > m_bandLimitedTables;
+};
+
+} // namespace WebCore
+
+#endif // PeriodicWave_h