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diff --git a/Source/WebCore/platform/audio/AudioResamplerKernel.h b/Source/WebCore/platform/audio/AudioResamplerKernel.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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. 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 INC. 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 AudioResamplerKernel_h
+#define AudioResamplerKernel_h
+
+#include "AudioArray.h"
+
+namespace WebCore {
+
+class AudioResampler;
+
+// AudioResamplerKernel does resampling on a single mono channel.
+// It uses a simple linear interpolation for good performance.
+
+class AudioResamplerKernel {
+public:
+    AudioResamplerKernel(AudioResampler*);
+
+    // getSourcePointer() should be called each time before process() is called.
+    // Given a number of frames to process (for subsequent call to process()), it returns a pointer and numberOfSourceFramesNeeded
+    // where sample data should be copied. This sample data provides the input to the resampler when process() is called.
+    // framesToProcess must be less than or equal to MaxFramesToProcess.
+    float* getSourcePointer(size_t framesToProcess, size_t* numberOfSourceFramesNeeded);
+
+    // process() resamples framesToProcess frames from the source into destination.
+    // Each call to process() must be preceded by a call to getSourcePointer() so that source input may be supplied.
+    // framesToProcess must be less than or equal to MaxFramesToProcess.
+    void process(float* destination, size_t framesToProcess);
+
+    // Resets the processing state.
+    void reset();
+
+    static const size_t MaxFramesToProcess;
+
+private:
+    double rate() const;
+
+    AudioResampler* m_resampler;
+    AudioFloatArray m_sourceBuffer;
+    
+    // This is a (floating point) read index on the input stream.
+    double m_virtualReadIndex;
+
+    // We need to have continuity from one call of process() to the next.
+    // m_lastValues stores the last two sample values from the last call to process().
+    // m_fillIndex represents how many buffered samples we have which can be as many as 2.
+    // For the first call to process() (or after reset()) there will be no buffered samples.
+    float m_lastValues[2];
+    unsigned m_fillIndex;
+};
+
+} // namespace WebCore
+
+#endif // AudioResamplerKernel_h