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diff --git a/Source/WebCore/platform/audio/SincResampler.h b/Source/WebCore/platform/audio/SincResampler.h
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+/*
+ * Copyright (C) 2011 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 SincResampler_h
+#define SincResampler_h
+
+#include "AudioArray.h"
+
+namespace WebCore {
+
+// SincResampler is a high-quality sample-rate converter.
+
+class SincResampler {
+public:   
+    // scaleFactor == sourceSampleRate / destinationSampleRate
+    // kernelSize can be adjusted for quality (higher is better)
+    // numberOfKernelOffsets is used for interpolation and is the number of sub-sample kernel shifts.
+    SincResampler(double scaleFactor, unsigned kernelSize = 64, unsigned numberOfKernelOffsets = 32);
+    
+    // Processes numberOfSourceFrames from source to produce numberOfSourceFrames / scaleFactor frames in destination.
+    void process(float* source, float* destination, unsigned numberOfSourceFrames);
+    
+    // FIXME: we can add a process() method which takes an input source callback function for streaming applications
+    // where the entire input buffer is not all available.
+    
+protected:
+    void initializeKernel();
+    void consumeSource(float* buffer, unsigned numberOfSourceFrames);
+    
+    double m_scaleFactor;
+    unsigned m_kernelSize;
+    unsigned m_numberOfKernelOffsets;
+
+    // m_kernelStorage has m_numberOfKernelOffsets kernels back-to-back, each of size m_kernelSize.
+    // The kernel offsets are sub-sample shifts of a windowed sinc() shifted from 0.0 to 1.0 sample.
+    AudioFloatArray m_kernelStorage;
+    
+    // m_virtualSourceIndex is an index on the source input buffer with sub-sample precision.
+    // It must be double precision to avoid drift.
+    double m_virtualSourceIndex;
+    
+    // This is the number of destination frames we generate per processing pass on the buffer.
+    unsigned m_blockSize;
+
+    // Source is copied into this buffer for each processing pass.
+    AudioFloatArray m_inputBuffer;
+
+    float* m_source;
+    unsigned m_sourceFramesAvailable;
+};
+
+} // namespace WebCore
+
+#endif // SincResampler_h