DO NOT COMMIT. Diff of downstream webrtc resampler commit for review purposes.

media/base/sinc_resampler.h

Index: media/base/sinc_resampler.h
diff --git a/media/base/sinc_resampler.h b/media/base/sinc_resampler.h
index facd1a106df27b7d3a2cdc6165f358177958f46e..60abd6128f9306171b744eec8be3a729224d3294 100644
--- a/media/base/sinc_resampler.h
+++ b/media/base/sinc_resampler.h
@@ -1,21 +1,45 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef MEDIA_BASE_SINC_RESAMPLER_H_
-#define MEDIA_BASE_SINC_RESAMPLER_H_
+/*
+ *  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.
+ */
+
+// Modified from the Chromium original here:
+// src/media/base/sinc_resampler.h
+
+#ifndef WEBRTC_COMMON_AUDIO_RESAMPLER_SINC_RESAMPLER_H_
+#define WEBRTC_COMMON_AUDIO_RESAMPLER_SINC_RESAMPLER_H_
+
+#include "webrtc/system_wrappers/interface/aligned_malloc.h"
+#include "webrtc/system_wrappers/interface/constructor_magic.h"
+#include "webrtc/system_wrappers/interface/scoped_ptr.h"
+#include "webrtc/test/testsupport/gtest_prod_util.h"
+#include "webrtc/typedefs.h"
+
+#if (defined(WEBRTC_ARCH_X86_FAMILY) && !defined(WEBRTC_IOS) &&  \
+        !defined(__SSE__)) ||  \
+    (defined(WEBRTC_ARCH_ARM_V7) && !defined(WEBRTC_ARCH_ARM_NEON))
+// Convenience define.
+#define WEBRTC_RESAMPLER_CPU_DETECTION
+#endif
 
-#include "base/callback.h"
-#include "base/gtest_prod_util.h"
-#include "base/memory/aligned_memory.h"
-#include "base/memory/scoped_ptr.h"
-#include "build/build_config.h"
-#include "media/base/media_export.h"
+namespace webrtc {
 
-namespace media {
+// Callback class for providing more data into the resampler.  Expects |frames|
+// of data to be rendered into |destination|; zero padded if not enough frames
+// are available to satisfy the request.
+class SincResamplerCallback {
+ public:
+  virtual ~SincResamplerCallback() {}
+  virtual void Run(int frames, float* destination) = 0;
+};
 
 // SincResampler is a high-quality single-channel sample-rate converter.
-class MEDIA_EXPORT SincResampler {
+class SincResampler {
  public:
   enum {
     // The kernel size can be adjusted for quality (higher is better) at the
@@ -34,15 +58,6 @@ class MEDIA_EXPORT SincResampler {
     kKernelStorageSize = kKernelSize * (kKernelOffsetCount + 1),
   };
 
-  // Selects runtime specific CPU features like SSE.  Must be called before
-  // using SincResampler.
-  static void InitializeCPUSpecificFeatures();
-
-  // Callback type for providing more data into the resampler.  Expects |frames|
-  // of data to be rendered into |destination|; zero padded if not enough frames
-  // are available to satisfy the request.
-  typedef base::Callback<void(int frames, float* destination)> ReadCB;
-
   // Constructs a SincResampler with the specified |read_cb|, which is used to
   // acquire audio data for resampling.  |io_sample_rate_ratio| is the ratio
   // of input / output sample rates.  |request_frames| controls the size in
@@ -51,7 +66,7 @@ class MEDIA_EXPORT SincResampler {
   // request size constraints.
   SincResampler(double io_sample_rate_ratio,
                 int request_frames,
-                const ReadCB& read_cb);
+                SincResamplerCallback* read_cb);
   virtual ~SincResampler();
 
   // Resample |frames| of data from |read_cb_| into |destination|.
@@ -61,6 +76,8 @@ class MEDIA_EXPORT SincResampler {
   // single call to |read_cb_| for more data.
   int ChunkSize() const;
 
+  int request_frames() const { return request_frames_; }
+
   // Flush all buffered data and reset internal indices.  Not thread safe, do
   // not call while Resample() is in progress.
   void Flush();
@@ -68,6 +85,9 @@ class MEDIA_EXPORT SincResampler {
   // Update |io_sample_rate_ratio_|.  SetRatio() will cause a reconstruction of
   // the kernels used for resampling.  Not thread safe, do not call while
   // Resample() is in progress.
+  //
+  // TODO(ajm): Use this in PushSincResampler rather than reconstructing
+  // SincResampler.  We would also need a way to update |request_frames_|.
   void SetRatio(double io_sample_rate_ratio);
 
   float* get_kernel_for_testing() { return kernel_storage_.get(); }
@@ -79,17 +99,23 @@ class MEDIA_EXPORT SincResampler {
   void InitializeKernel();
   void UpdateRegions(bool second_load);
 
+  // Selects runtime specific CPU features like SSE.  Must be called before
+  // using SincResampler.
+  // TODO(ajm): Currently managed by the class internally. See the note with
+  // |convolve_proc_| below.
+  void InitializeCPUSpecificFeatures();
+
   // Compute convolution of |k1| and |k2| over |input_ptr|, resultant sums are
   // linearly interpolated using |kernel_interpolation_factor|.  On x86, the
   // underlying implementation is chosen at run time based on SSE support.  On
   // ARM, NEON support is chosen at compile time based on compilation flags.
   static float Convolve_C(const float* input_ptr, const float* k1,
                           const float* k2, double kernel_interpolation_factor);
-#if defined(ARCH_CPU_X86_FAMILY)
+#if defined(WEBRTC_ARCH_X86_FAMILY)
   static float Convolve_SSE(const float* input_ptr, const float* k1,
                             const float* k2,
                             double kernel_interpolation_factor);
-#elif defined(ARCH_CPU_ARM_FAMILY) && defined(USE_NEON)
+#elif defined(WEBRTC_ARCH_ARM_V7)
   static float Convolve_NEON(const float* input_ptr, const float* k1,
                              const float* k2,
                              double kernel_interpolation_factor);
@@ -106,7 +132,7 @@ class MEDIA_EXPORT SincResampler {
   bool buffer_primed_;
 
   // Source of data for resampling.
-  const ReadCB read_cb_;
+  SincResamplerCallback* read_cb_;
 
   // The size (in samples) to request from each |read_cb_| execution.
   const int request_frames_;
@@ -120,12 +146,22 @@ class MEDIA_EXPORT SincResampler {
   // Contains kKernelOffsetCount kernels back-to-back, each of size kKernelSize.
   // The kernel offsets are sub-sample shifts of a windowed sinc shifted from
   // 0.0 to 1.0 sample.
-  scoped_ptr<float[], base::ScopedPtrAlignedFree> kernel_storage_;
-  scoped_ptr<float[], base::ScopedPtrAlignedFree> kernel_pre_sinc_storage_;
-  scoped_ptr<float[], base::ScopedPtrAlignedFree> kernel_window_storage_;
+  scoped_ptr_malloc<float, AlignedFree> kernel_storage_;
+  scoped_ptr_malloc<float, AlignedFree> kernel_pre_sinc_storage_;
+  scoped_ptr_malloc<float, AlignedFree> kernel_window_storage_;
 
   // Data from the source is copied into this buffer for each processing pass.
-  scoped_ptr<float[], base::ScopedPtrAlignedFree> input_buffer_;
+  scoped_ptr_malloc<float, AlignedFree> input_buffer_;
+
+  // Stores the runtime selection of which Convolve function to use.
+  // TODO(ajm): Move to using a global static which must only be initialized
+  // once by the user. We're not doing this initially, because we don't have
+  // e.g. a LazyInstance helper in webrtc.
+#if defined(WEBRTC_RESAMPLER_CPU_DETECTION)
+  typedef float (*ConvolveProc)(const float*, const float*, const float*,
+                                double);
+  ConvolveProc convolve_proc_;
+#endif
 
   // Pointers to the various regions inside |input_buffer_|.  See the diagram at
   // the top of the .cc file for more information.
@@ -138,6 +174,6 @@ class MEDIA_EXPORT SincResampler {
   DISALLOW_COPY_AND_ASSIGN(SincResampler);
 };
 
-}  // namespace media
+}  // namespace webrtc
 
-#endif  // MEDIA_BASE_SINC_RESAMPLER_H_
+#endif  // WEBRTC_COMMON_AUDIO_RESAMPLER_SINC_RESAMPLER_H_