Break out SSE functions into new media_sse target.

media/base/sinc_resampler.h

 // 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_
 
 #include "base/callback.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/aligned_memory.h"
 #include "base/memory/scoped_ptr.h"
 #include "media/base/media_export.h"
 
 namespace media {
 
 // SincResampler is a high-quality single-channel sample-rate converter.
 class MEDIA_EXPORT SincResampler {
  public:
-  // The maximum number of samples that may be requested from the callback ahead
-  // of the current position in the stream.
-  static const int kMaximumLookAheadSize;
+  enum {
+    // The kernel size can be adjusted for quality (higher is better) at the
+    // expense of performance.  Must be a multiple of 32.
+    // TODO(dalecurtis): Test performance to see if we can jack this up to 64+.
+    kKernelSize = 32,
+
+    // The number of destination frames generated per processing pass.  Affects
+    // how often and for how much SincResampler calls back for input.  Must be
+    // greater than kKernelSize.
+    kBlockSize = 512,
+
+    // The kernel offset count is used for interpolation and is the number of
+    // sub-sample kernel shifts.  Can be adjusted for quality (higher is better)
+    // at the expense of allocating more memory.
+    kKernelOffsetCount = 32,
+    kKernelStorageSize = kKernelSize * (kKernelOffsetCount + 1),
+
+    // The size (in samples) of the internal buffer used by the resampler.
+    kBufferSize = kBlockSize + kKernelSize,
+
+    // The maximum number of samples that may be requested from the callback
+    // ahead of the current position in the stream.
+    kMaximumLookAheadSize = kBufferSize
+  };
 
   // 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(float* destination, int frames)> 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.
   SincResampler(double io_sample_rate_ratio, const ReadCB& read_cb);
   virtual ~SincResampler();
 
   // Resample |frames| of data from |read_cb_| into |destination|.
   void Resample(float* destination, int frames);
 
   // The maximum size in frames that guarantees Resample() will only make a
   // single call to |read_cb_| for more data.
-  int ChunkSize();
+  int ChunkSize() const;
 
   // Flush all buffered data and reset internal indices.
   void Flush();
 
  private:
   FRIEND_TEST_ALL_PREFIXES(SincResamplerTest, Convolve);
   FRIEND_TEST_ALL_PREFIXES(SincResamplerTest, ConvolveBenchmark);
 
   void InitializeKernel();
 
   // 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(const float* input_ptr, const float* k1,
                         const float* k2, double kernel_interpolation_factor);
   static float Convolve_C(const float* input_ptr, const float* k1,
                           const float* k2, double kernel_interpolation_factor);
   static float Convolve_SSE(const float* input_ptr, const float* k1,

[Mark Mentovai, 2013/03/05 21:32:31]

Can you wrap Convolve_SSE and Convolve_NEON in the appropriate #ifdefs to avoid
exposing the declarations on irrelevant architectures?

Same for FMAC_SSE in media/base/vector_math_testing.h.

[DaleCurtis, 2013/03/05 21:51:37]

Done.

                             const float* k2,
                             double kernel_interpolation_factor);
   static float Convolve_NEON(const float* input_ptr, const float* k1,
                              const float* k2,
                              double kernel_interpolation_factor);
 
   // The ratio of input / output sample rates.
-  double io_sample_rate_ratio_;
+  const double io_sample_rate_ratio_;
 
   // An index on the source input buffer with sub-sample precision.  It must be
   // double precision to avoid drift.
   double virtual_source_idx_;
 
   // The buffer is primed once at the very beginning of processing.
   bool buffer_primed_;
 
   // Source of data for resampling.
   ReadCB read_cb_;
@@ skipping 14 matching lines @@
   float* const r3_;
   float* const r4_;
   float* const r5_;
 
   DISALLOW_COPY_AND_ASSIGN(SincResampler);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_SINC_RESAMPLER_H_