Varispeed support for SincResampler.

media/base/sinc_resampler_unittest.cc

 // 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.
 
 // MSVC++ requires this to be set before any other includes to get M_PI.
 #define _USE_MATH_DEFINES
 
 #include <cmath>
 
 #include "base/bind.h"
@@ skipping 80 matching lines @@
   // Flush and request more data, which should all be zeros now.
   resampler.Flush();
   testing::Mock::VerifyAndClear(&mock_source);
   EXPECT_CALL(mock_source, ProvideInput(_, _))
       .Times(1).WillOnce(ClearBuffer());
   resampler.Resample(resampled_destination.get(), resampler.ChunkSize() / 2);
   for (int i = 0; i < resampler.ChunkSize() / 2; ++i)
     ASSERT_FLOAT_EQ(resampled_destination[i], 0);
 }
 
+// Test flush resets the internal state properly.
+TEST(SincResamplerTest, DISABLED_SetRatioBench) {
+  MockSource mock_source;
+  SincResampler resampler(
+      kSampleRateRatio,
+      base::Bind(&MockSource::ProvideInput, base::Unretained(&mock_source)));
+
+  base::TimeTicks start = base::TimeTicks::HighResNow();
+  for (int i = 1; i < 10000; ++i)
+    resampler.SetRatio(1.0 / i);

[Chris Rogers, 2013/04/16 22:57:02]

These are pretty insanely low ratio values!  But, I suppose it's just testing
the timing.

You might want to change to SetRatio(1.0 + 1.0/i)

[DaleCurtis, 2013/04/16 23:03:12]

Correct, it's just a timing test, so this is fine.

+  double total_time_c_ms =
+      (base::TimeTicks::HighResNow() - start).InMillisecondsF();
+  printf("SetRatio() took %.2fms.\n", total_time_c_ms);
+}
+
+
 // Define platform independent function name for Convolve* tests.
 #if defined(ARCH_CPU_X86_FAMILY)
 #define CONVOLVE_FUNC Convolve_SSE
 #elif defined(ARCH_CPU_ARM_FAMILY) && defined(USE_NEON)
 #define CONVOLVE_FUNC Convolve_NEON
 #endif
 
 // Ensure various optimized Convolve() methods return the same value.  Only run
 // this test if other optimized methods exist, otherwise the default Convolve()
 // will be tested by the parameterized SincResampler tests below.
@@ skipping 181 matching lines @@
   int input_samples = kTestDurationSecs * input_rate_;
   int output_samples = kTestDurationSecs * output_rate_;
 
   // Nyquist frequency for the input sampling rate.
   double input_nyquist_freq = 0.5 * input_rate_;
 
   // Source for data to be resampled.
   SinusoidalLinearChirpSource resampler_source(
       input_rate_, input_samples, input_nyquist_freq);
 
+  const double io_ratio = input_rate_ / static_cast<double>(output_rate_);
   SincResampler resampler(
-      input_rate_ / static_cast<double>(output_rate_),
+      io_ratio,
       base::Bind(&SinusoidalLinearChirpSource::ProvideInput,
                  base::Unretained(&resampler_source)));
 
+  // Force an update to the sample rate ratio to ensure dyanmic sample rate
+  // changes are working correctly.
+  scoped_ptr<float[]> kernel(new float[SincResampler::kKernelStorageSize]);
+  memcpy(kernel.get(), resampler.get_kernel_for_testing(),
+         SincResampler::kKernelStorageSize);
+  resampler.SetRatio(M_PI);
+  ASSERT_NE(0, memcmp(kernel.get(), resampler.get_kernel_for_testing(),
+                      SincResampler::kKernelStorageSize));
+  resampler.SetRatio(io_ratio);
+  ASSERT_EQ(0, memcmp(kernel.get(), resampler.get_kernel_for_testing(),
+                      SincResampler::kKernelStorageSize));
+
   // TODO(dalecurtis): If we switch to AVX/SSE optimization, we'll need to
   // allocate these on 32-byte boundaries and ensure they're sized % 32 bytes.
   scoped_ptr<float[]> resampled_destination(new float[output_samples]);
   scoped_ptr<float[]> pure_destination(new float[output_samples]);
 
   // Generate resampled signal.
   resampler.Resample(resampled_destination.get(), output_samples);
 
   // Generate pure signal.
   SinusoidalLinearChirpSource pure_source(
@@ skipping 88 matching lines @@
         std::tr1::make_tuple(11025, 192000, kResamplingRMSError, -62.61),
         std::tr1::make_tuple(16000, 192000, kResamplingRMSError, -63.14),
         std::tr1::make_tuple(22050, 192000, kResamplingRMSError, -62.42),
         std::tr1::make_tuple(32000, 192000, kResamplingRMSError, -63.38),
         std::tr1::make_tuple(44100, 192000, kResamplingRMSError, -62.63),
         std::tr1::make_tuple(48000, 192000, kResamplingRMSError, -73.44),
         std::tr1::make_tuple(96000, 192000, kResamplingRMSError, -73.52),
         std::tr1::make_tuple(192000, 192000, kResamplingRMSError, -73.52)));
 
 }  // namespace media