1 /*
2 * Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 // Modified from the Chromium original:
12 // src/media/base/sinc_resampler_unittest.cc
13
14 // MSVC++ requires this to be set before any other includes to get M_PI.
15 #define _USE_MATH_DEFINES
16
17 #include <math.h>
18
19 #include "testing/gmock/include/gmock/gmock.h"
20 #include "testing/gtest/include/gtest/gtest.h"
21 #include "webrtc/common_audio/resampler/sinc_resampler.h"
22 #include "webrtc/common_audio/resampler/sinusoidal_linear_chirp_source.h"
23 #include "webrtc/system_wrappers/interface/cpu_features_wrapper.h"
24 #include "webrtc/system_wrappers/interface/scoped_ptr.h"
25 #include "webrtc/system_wrappers/interface/stringize_macros.h"
26 #include "webrtc/system_wrappers/interface/tick_util.h"
27 #include "webrtc/test/test_suite.h"
28
29 using testing::_;
30
31 namespace webrtc {
32
33 static const double kSampleRateRatio = 192000.0 / 44100.0;
34 static const double kKernelInterpolationFactor = 0.5;
35
36 // Helper class to ensure ChunkedResample() functions properly.
37 class MockSource : public SincResamplerCallback {
38 public:
39 MOCK_METHOD2(Run, void(int frames, float* destination));
40 };
41
ACTION(ClearBuffer)42 ACTION(ClearBuffer) {
43 memset(arg1, 0, arg0 * sizeof(float));
44 }
45
ACTION(FillBuffer)46 ACTION(FillBuffer) {
47 // Value chosen arbitrarily such that SincResampler resamples it to something
48 // easily representable on all platforms; e.g., using kSampleRateRatio this
49 // becomes 1.81219.
50 memset(arg1, 64, arg0 * sizeof(float));
51 }
52
53 // Test requesting multiples of ChunkSize() frames results in the proper number
54 // of callbacks.
TEST(SincResamplerTest,ChunkedResample)55 TEST(SincResamplerTest, ChunkedResample) {
56 MockSource mock_source;
57
58 // Choose a high ratio of input to output samples which will result in quick
59 // exhaustion of SincResampler's internal buffers.
60 SincResampler resampler(kSampleRateRatio, SincResampler::kDefaultRequestSize,
61 &mock_source);
62
63 static const int kChunks = 2;
64 int max_chunk_size = resampler.ChunkSize() * kChunks;
65 scoped_ptr<float[]> resampled_destination(new float[max_chunk_size]);
66
67 // Verify requesting ChunkSize() frames causes a single callback.
68 EXPECT_CALL(mock_source, Run(_, _))
69 .Times(1).WillOnce(ClearBuffer());
70 resampler.Resample(resampler.ChunkSize(), resampled_destination.get());
71
72 // Verify requesting kChunks * ChunkSize() frames causes kChunks callbacks.
73 testing::Mock::VerifyAndClear(&mock_source);
74 EXPECT_CALL(mock_source, Run(_, _))
75 .Times(kChunks).WillRepeatedly(ClearBuffer());
76 resampler.Resample(max_chunk_size, resampled_destination.get());
77 }
78
79 // Test flush resets the internal state properly.
TEST(SincResamplerTest,Flush)80 TEST(SincResamplerTest, Flush) {
81 MockSource mock_source;
82 SincResampler resampler(kSampleRateRatio, SincResampler::kDefaultRequestSize,
83 &mock_source);
84 scoped_ptr<float[]> resampled_destination(new float[resampler.ChunkSize()]);
85
86 // Fill the resampler with junk data.
87 EXPECT_CALL(mock_source, Run(_, _))
88 .Times(1).WillOnce(FillBuffer());
89 resampler.Resample(resampler.ChunkSize() / 2, resampled_destination.get());
90 ASSERT_NE(resampled_destination[0], 0);
91
92 // Flush and request more data, which should all be zeros now.
93 resampler.Flush();
94 testing::Mock::VerifyAndClear(&mock_source);
95 EXPECT_CALL(mock_source, Run(_, _))
96 .Times(1).WillOnce(ClearBuffer());
97 resampler.Resample(resampler.ChunkSize() / 2, resampled_destination.get());
98 for (int i = 0; i < resampler.ChunkSize() / 2; ++i)
99 ASSERT_FLOAT_EQ(resampled_destination[i], 0);
100 }
101
102 // Test flush resets the internal state properly.
TEST(SincResamplerTest,DISABLED_SetRatioBench)103 TEST(SincResamplerTest, DISABLED_SetRatioBench) {
104 MockSource mock_source;
105 SincResampler resampler(kSampleRateRatio, SincResampler::kDefaultRequestSize,
106 &mock_source);
107
108 TickTime start = TickTime::Now();
109 for (int i = 1; i < 10000; ++i)
110 resampler.SetRatio(1.0 / i);
111 double total_time_c_us = (TickTime::Now() - start).Microseconds();
112 printf("SetRatio() took %.2fms.\n", total_time_c_us / 1000);
113 }
114
115
116 // Define platform independent function name for Convolve* tests.
117 #if defined(WEBRTC_ARCH_X86_FAMILY)
118 #define CONVOLVE_FUNC Convolve_SSE
119 #elif defined(WEBRTC_ARCH_ARM_V7)
120 #define CONVOLVE_FUNC Convolve_NEON
121 #endif
122
123 // Ensure various optimized Convolve() methods return the same value. Only run
124 // this test if other optimized methods exist, otherwise the default Convolve()
125 // will be tested by the parameterized SincResampler tests below.
126 #if defined(CONVOLVE_FUNC)
TEST(SincResamplerTest,Convolve)127 TEST(SincResamplerTest, Convolve) {
128 #if defined(WEBRTC_ARCH_X86_FAMILY)
129 ASSERT_TRUE(WebRtc_GetCPUInfo(kSSE2));
130 #elif defined(WEBRTC_ARCH_ARM_V7)
131 ASSERT_TRUE(WebRtc_GetCPUFeaturesARM() & kCPUFeatureNEON);
132 #endif
133
134 // Initialize a dummy resampler.
135 MockSource mock_source;
136 SincResampler resampler(kSampleRateRatio, SincResampler::kDefaultRequestSize,
137 &mock_source);
138
139 // The optimized Convolve methods are slightly more precise than Convolve_C(),
140 // so comparison must be done using an epsilon.
141 static const double kEpsilon = 0.00000005;
142
143 // Use a kernel from SincResampler as input and kernel data, this has the
144 // benefit of already being properly sized and aligned for Convolve_SSE().
145 double result = resampler.Convolve_C(
146 resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
147 resampler.kernel_storage_.get(), kKernelInterpolationFactor);
148 double result2 = resampler.CONVOLVE_FUNC(
149 resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
150 resampler.kernel_storage_.get(), kKernelInterpolationFactor);
151 EXPECT_NEAR(result2, result, kEpsilon);
152
153 // Test Convolve() w/ unaligned input pointer.
154 result = resampler.Convolve_C(
155 resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
156 resampler.kernel_storage_.get(), kKernelInterpolationFactor);
157 result2 = resampler.CONVOLVE_FUNC(
158 resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
159 resampler.kernel_storage_.get(), kKernelInterpolationFactor);
160 EXPECT_NEAR(result2, result, kEpsilon);
161 }
162 #endif
163
164 // Benchmark for the various Convolve() methods. Make sure to build with
165 // branding=Chrome so that DCHECKs are compiled out when benchmarking. Original
166 // benchmarks were run with --convolve-iterations=50000000.
TEST(SincResamplerTest,ConvolveBenchmark)167 TEST(SincResamplerTest, ConvolveBenchmark) {
168 // Initialize a dummy resampler.
169 MockSource mock_source;
170 SincResampler resampler(kSampleRateRatio, SincResampler::kDefaultRequestSize,
171 &mock_source);
172
173 // Retrieve benchmark iterations from command line.
174 // TODO(ajm): Reintroduce this as a command line option.
175 const int kConvolveIterations = 1000000;
176
177 printf("Benchmarking %d iterations:\n", kConvolveIterations);
178
179 // Benchmark Convolve_C().
180 TickTime start = TickTime::Now();
181 for (int i = 0; i < kConvolveIterations; ++i) {
182 resampler.Convolve_C(
183 resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
184 resampler.kernel_storage_.get(), kKernelInterpolationFactor);
185 }
186 double total_time_c_us = (TickTime::Now() - start).Microseconds();
187 printf("Convolve_C took %.2fms.\n", total_time_c_us / 1000);
188
189 #if defined(CONVOLVE_FUNC)
190 #if defined(WEBRTC_ARCH_X86_FAMILY)
191 ASSERT_TRUE(WebRtc_GetCPUInfo(kSSE2));
192 #elif defined(WEBRTC_ARCH_ARM_V7)
193 ASSERT_TRUE(WebRtc_GetCPUFeaturesARM() & kCPUFeatureNEON);
194 #endif
195
196 // Benchmark with unaligned input pointer.
197 start = TickTime::Now();
198 for (int j = 0; j < kConvolveIterations; ++j) {
199 resampler.CONVOLVE_FUNC(
200 resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
201 resampler.kernel_storage_.get(), kKernelInterpolationFactor);
202 }
203 double total_time_optimized_unaligned_us =
204 (TickTime::Now() - start).Microseconds();
205 printf(STRINGIZE(CONVOLVE_FUNC) "(unaligned) took %.2fms; which is %.2fx "
206 "faster than Convolve_C.\n", total_time_optimized_unaligned_us / 1000,
207 total_time_c_us / total_time_optimized_unaligned_us);
208
209 // Benchmark with aligned input pointer.
210 start = TickTime::Now();
211 for (int j = 0; j < kConvolveIterations; ++j) {
212 resampler.CONVOLVE_FUNC(
213 resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
214 resampler.kernel_storage_.get(), kKernelInterpolationFactor);
215 }
216 double total_time_optimized_aligned_us =
217 (TickTime::Now() - start).Microseconds();
218 printf(STRINGIZE(CONVOLVE_FUNC) " (aligned) took %.2fms; which is %.2fx "
219 "faster than Convolve_C and %.2fx faster than "
220 STRINGIZE(CONVOLVE_FUNC) " (unaligned).\n",
221 total_time_optimized_aligned_us / 1000,
222 total_time_c_us / total_time_optimized_aligned_us,
223 total_time_optimized_unaligned_us / total_time_optimized_aligned_us);
224 #endif
225 }
226
227 #undef CONVOLVE_FUNC
228
229 typedef std::tr1::tuple<int, int, double, double> SincResamplerTestData;
230 class SincResamplerTest
231 : public testing::TestWithParam<SincResamplerTestData> {
232 public:
SincResamplerTest()233 SincResamplerTest()
234 : input_rate_(std::tr1::get<0>(GetParam())),
235 output_rate_(std::tr1::get<1>(GetParam())),
236 rms_error_(std::tr1::get<2>(GetParam())),
237 low_freq_error_(std::tr1::get<3>(GetParam())) {
238 }
239
~SincResamplerTest()240 virtual ~SincResamplerTest() {}
241
242 protected:
243 int input_rate_;
244 int output_rate_;
245 double rms_error_;
246 double low_freq_error_;
247 };
248
249 // Tests resampling using a given input and output sample rate.
TEST_P(SincResamplerTest,Resample)250 TEST_P(SincResamplerTest, Resample) {
251 // Make comparisons using one second of data.
252 static const double kTestDurationSecs = 1;
253 const int input_samples = kTestDurationSecs * input_rate_;
254 const int output_samples = kTestDurationSecs * output_rate_;
255
256 // Nyquist frequency for the input sampling rate.
257 const double input_nyquist_freq = 0.5 * input_rate_;
258
259 // Source for data to be resampled.
260 SinusoidalLinearChirpSource resampler_source(
261 input_rate_, input_samples, input_nyquist_freq, 0);
262
263 const double io_ratio = input_rate_ / static_cast<double>(output_rate_);
264 SincResampler resampler(io_ratio, SincResampler::kDefaultRequestSize,
265 &resampler_source);
266
267 // Force an update to the sample rate ratio to ensure dyanmic sample rate
268 // changes are working correctly.
269 scoped_ptr<float[]> kernel(new float[SincResampler::kKernelStorageSize]);
270 memcpy(kernel.get(), resampler.get_kernel_for_testing(),
271 SincResampler::kKernelStorageSize);
272 resampler.SetRatio(M_PI);
273 ASSERT_NE(0, memcmp(kernel.get(), resampler.get_kernel_for_testing(),
274 SincResampler::kKernelStorageSize));
275 resampler.SetRatio(io_ratio);
276 ASSERT_EQ(0, memcmp(kernel.get(), resampler.get_kernel_for_testing(),
277 SincResampler::kKernelStorageSize));
278
279 // TODO(dalecurtis): If we switch to AVX/SSE optimization, we'll need to
280 // allocate these on 32-byte boundaries and ensure they're sized % 32 bytes.
281 scoped_ptr<float[]> resampled_destination(new float[output_samples]);
282 scoped_ptr<float[]> pure_destination(new float[output_samples]);
283
284 // Generate resampled signal.
285 resampler.Resample(output_samples, resampled_destination.get());
286
287 // Generate pure signal.
288 SinusoidalLinearChirpSource pure_source(
289 output_rate_, output_samples, input_nyquist_freq, 0);
290 pure_source.Run(output_samples, pure_destination.get());
291
292 // Range of the Nyquist frequency (0.5 * min(input rate, output_rate)) which
293 // we refer to as low and high.
294 static const double kLowFrequencyNyquistRange = 0.7;
295 static const double kHighFrequencyNyquistRange = 0.9;
296
297 // Calculate Root-Mean-Square-Error and maximum error for the resampling.
298 double sum_of_squares = 0;
299 double low_freq_max_error = 0;
300 double high_freq_max_error = 0;
301 int minimum_rate = std::min(input_rate_, output_rate_);
302 double low_frequency_range = kLowFrequencyNyquistRange * 0.5 * minimum_rate;
303 double high_frequency_range = kHighFrequencyNyquistRange * 0.5 * minimum_rate;
304 for (int i = 0; i < output_samples; ++i) {
305 double error = fabs(resampled_destination[i] - pure_destination[i]);
306
307 if (pure_source.Frequency(i) < low_frequency_range) {
308 if (error > low_freq_max_error)
309 low_freq_max_error = error;
310 } else if (pure_source.Frequency(i) < high_frequency_range) {
311 if (error > high_freq_max_error)
312 high_freq_max_error = error;
313 }
314 // TODO(dalecurtis): Sanity check frequencies > kHighFrequencyNyquistRange.
315
316 sum_of_squares += error * error;
317 }
318
319 double rms_error = sqrt(sum_of_squares / output_samples);
320
321 // Convert each error to dbFS.
322 #define DBFS(x) 20 * log10(x)
323 rms_error = DBFS(rms_error);
324 low_freq_max_error = DBFS(low_freq_max_error);
325 high_freq_max_error = DBFS(high_freq_max_error);
326
327 EXPECT_LE(rms_error, rms_error_);
328 EXPECT_LE(low_freq_max_error, low_freq_error_);
329
330 // All conversions currently have a high frequency error around -6 dbFS.
331 static const double kHighFrequencyMaxError = -6.02;
332 EXPECT_LE(high_freq_max_error, kHighFrequencyMaxError);
333 }
334
335 // Almost all conversions have an RMS error of around -14 dbFS.
336 static const double kResamplingRMSError = -14.58;
337
338 // Thresholds chosen arbitrarily based on what each resampling reported during
339 // testing. All thresholds are in dbFS, http://en.wikipedia.org/wiki/DBFS.
340 INSTANTIATE_TEST_CASE_P(
341 SincResamplerTest, SincResamplerTest, testing::Values(
342 // To 44.1kHz
343 std::tr1::make_tuple(8000, 44100, kResamplingRMSError, -62.73),
344 std::tr1::make_tuple(11025, 44100, kResamplingRMSError, -72.19),
345 std::tr1::make_tuple(16000, 44100, kResamplingRMSError, -62.54),
346 std::tr1::make_tuple(22050, 44100, kResamplingRMSError, -73.53),
347 std::tr1::make_tuple(32000, 44100, kResamplingRMSError, -63.32),
348 std::tr1::make_tuple(44100, 44100, kResamplingRMSError, -73.53),
349 std::tr1::make_tuple(48000, 44100, -15.01, -64.04),
350 std::tr1::make_tuple(96000, 44100, -18.49, -25.51),
351 std::tr1::make_tuple(192000, 44100, -20.50, -13.31),
352
353 // To 48kHz
354 std::tr1::make_tuple(8000, 48000, kResamplingRMSError, -63.43),
355 std::tr1::make_tuple(11025, 48000, kResamplingRMSError, -62.61),
356 std::tr1::make_tuple(16000, 48000, kResamplingRMSError, -63.96),
357 std::tr1::make_tuple(22050, 48000, kResamplingRMSError, -62.42),
358 std::tr1::make_tuple(32000, 48000, kResamplingRMSError, -64.04),
359 std::tr1::make_tuple(44100, 48000, kResamplingRMSError, -62.63),
360 std::tr1::make_tuple(48000, 48000, kResamplingRMSError, -73.52),
361 std::tr1::make_tuple(96000, 48000, -18.40, -28.44),
362 std::tr1::make_tuple(192000, 48000, -20.43, -14.11),
363
364 // To 96kHz
365 std::tr1::make_tuple(8000, 96000, kResamplingRMSError, -63.19),
366 std::tr1::make_tuple(11025, 96000, kResamplingRMSError, -62.61),
367 std::tr1::make_tuple(16000, 96000, kResamplingRMSError, -63.39),
368 std::tr1::make_tuple(22050, 96000, kResamplingRMSError, -62.42),
369 std::tr1::make_tuple(32000, 96000, kResamplingRMSError, -63.95),
370 std::tr1::make_tuple(44100, 96000, kResamplingRMSError, -62.63),
371 std::tr1::make_tuple(48000, 96000, kResamplingRMSError, -73.52),
372 std::tr1::make_tuple(96000, 96000, kResamplingRMSError, -73.52),
373 std::tr1::make_tuple(192000, 96000, kResamplingRMSError, -28.41),
374
375 // To 192kHz
376 std::tr1::make_tuple(8000, 192000, kResamplingRMSError, -63.10),
377 std::tr1::make_tuple(11025, 192000, kResamplingRMSError, -62.61),
378 std::tr1::make_tuple(16000, 192000, kResamplingRMSError, -63.14),
379 std::tr1::make_tuple(22050, 192000, kResamplingRMSError, -62.42),
380 std::tr1::make_tuple(32000, 192000, kResamplingRMSError, -63.38),
381 std::tr1::make_tuple(44100, 192000, kResamplingRMSError, -62.63),
382 std::tr1::make_tuple(48000, 192000, kResamplingRMSError, -73.44),
383 std::tr1::make_tuple(96000, 192000, kResamplingRMSError, -73.52),
384 std::tr1::make_tuple(192000, 192000, kResamplingRMSError, -73.52)));
385
386 } // namespace webrtc
387