Update audio_processing module

Corresponds to upstream commit 524e9b043e7e86fd72353b987c9d5f6a1ebf83e1

Update notes:

 * Pull in third party license file

 * Replace .gypi files with BUILD.gn to keep track of what changes
   upstream

 * Bunch of new filse pulled in as dependencies

 * Won't build yet due to changes needed on top of these

webrtc/common_audio/resampler/include/push_resampler.h

@@ -0,0 +1,52 @@
+/*
+ *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_COMMON_AUDIO_RESAMPLER_INCLUDE_PUSH_RESAMPLER_H_
+#define WEBRTC_COMMON_AUDIO_RESAMPLER_INCLUDE_PUSH_RESAMPLER_H_
+
+#include "webrtc/base/scoped_ptr.h"
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+class PushSincResampler;
+
+// Wraps PushSincResampler to provide stereo support.
+// TODO(ajm): add support for an arbitrary number of channels.
+template <typename T>
+class PushResampler {
+ public:
+  PushResampler();
+  virtual ~PushResampler();
+
+  // Must be called whenever the parameters change. Free to be called at any
+  // time as it is a no-op if parameters have not changed since the last call.
+  int InitializeIfNeeded(int src_sample_rate_hz, int dst_sample_rate_hz,
+                         int num_channels);
+
+  // Returns the total number of samples provided in destination (e.g. 32 kHz,
+  // 2 channel audio gives 640 samples).
+  int Resample(const T* src, size_t src_length, T* dst, size_t dst_capacity);
+
+ private:
+  rtc::scoped_ptr<PushSincResampler> sinc_resampler_;
+  rtc::scoped_ptr<PushSincResampler> sinc_resampler_right_;
+  int src_sample_rate_hz_;
+  int dst_sample_rate_hz_;
+  int num_channels_;
+  rtc::scoped_ptr<T[]> src_left_;
+  rtc::scoped_ptr<T[]> src_right_;
+  rtc::scoped_ptr<T[]> dst_left_;
+  rtc::scoped_ptr<T[]> dst_right_;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_COMMON_AUDIO_RESAMPLER_INCLUDE_PUSH_RESAMPLER_H_

webrtc/common_audio/resampler/include/resampler.h

@@ -0,0 +1,95 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+/*
+ * A wrapper for resampling a numerous amount of sampling combinations.
+ */
+
+#ifndef WEBRTC_RESAMPLER_RESAMPLER_H_
+#define WEBRTC_RESAMPLER_RESAMPLER_H_
+
+#include <stddef.h>
+
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+// All methods return 0 on success and -1 on failure.
+class Resampler
+{
+
+public:
+    Resampler();
+    Resampler(int inFreq, int outFreq, int num_channels);
+    ~Resampler();
+
+    // Reset all states
+    int Reset(int inFreq, int outFreq, int num_channels);
+
+    // Reset all states if any parameter has changed
+    int ResetIfNeeded(int inFreq, int outFreq, int num_channels);
+
+    // Resample samplesIn to samplesOut.
+    int Push(const int16_t* samplesIn, size_t lengthIn, int16_t* samplesOut,
+             size_t maxLen, size_t &outLen);
+
+private:
+    enum ResamplerMode
+    {
+        kResamplerMode1To1,
+        kResamplerMode1To2,
+        kResamplerMode1To3,
+        kResamplerMode1To4,
+        kResamplerMode1To6,
+        kResamplerMode1To12,
+        kResamplerMode2To3,
+        kResamplerMode2To11,
+        kResamplerMode4To11,
+        kResamplerMode8To11,
+        kResamplerMode11To16,
+        kResamplerMode11To32,
+        kResamplerMode2To1,
+        kResamplerMode3To1,
+        kResamplerMode4To1,
+        kResamplerMode6To1,
+        kResamplerMode12To1,
+        kResamplerMode3To2,
+        kResamplerMode11To2,
+        kResamplerMode11To4,
+        kResamplerMode11To8
+    };
+
+    // Generic pointers since we don't know what states we'll need
+    void* state1_;
+    void* state2_;
+    void* state3_;
+
+    // Storage if needed
+    int16_t* in_buffer_;
+    int16_t* out_buffer_;
+    size_t in_buffer_size_;
+    size_t out_buffer_size_;
+    size_t in_buffer_size_max_;
+    size_t out_buffer_size_max_;
+
+    int my_in_frequency_khz_;
+    int my_out_frequency_khz_;
+    ResamplerMode my_mode_;
+    int num_channels_;
+
+    // Extra instance for stereo
+    Resampler* slave_left_;
+    Resampler* slave_right_;
+};
+
+}  // namespace webrtc
+
+#endif // WEBRTC_RESAMPLER_RESAMPLER_H_