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| author | swurl <swurl@swurl.xyz> | 2025-05-31 02:33:02 -0400 |
|---|---|---|
| committer | swurl <swurl@swurl.xyz> | 2025-05-31 02:33:02 -0400 |
| commit | 6c655321e6b04b8648802e296bb5ca11d290ae68 (patch) | |
| tree | 5c906511e4a2910ce8b806bb9d763b524c28619e /externals/oboe/tests/testResampler.cpp | |
| parent | c0cceff365f754f8859f4c9a0362ebdba7ea388b (diff) | |
Move dead submodules in-tree
Signed-off-by: swurl <swurl@swurl.xyz>
Diffstat (limited to 'externals/oboe/tests/testResampler.cpp')
| -rw-r--r-- | externals/oboe/tests/testResampler.cpp | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/externals/oboe/tests/testResampler.cpp b/externals/oboe/tests/testResampler.cpp new file mode 100644 index 0000000000..5518829bbd --- /dev/null +++ b/externals/oboe/tests/testResampler.cpp @@ -0,0 +1,225 @@ +/* + * Copyright 2022 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/* + * Test FlowGraph + */ + +#include "math.h" +#include "stdio.h" + +#include <gtest/gtest.h> +#include <oboe/Oboe.h> + +#include "flowgraph/resampler/MultiChannelResampler.h" + +using namespace oboe::resampler; + +// Measure zero crossings. +static int32_t countZeroCrossingsWithHysteresis(float *input, int32_t numSamples) { + const float kHysteresisLevel = 0.25f; + int zeroCrossingCount = 0; + int state = 0; // can be -1, 0, +1 + for (int i = 0; i < numSamples; i++) { + if (input[i] >= kHysteresisLevel) { + if (state < 0) { + zeroCrossingCount++; + } + state = 1; + } else if (input[i] <= -kHysteresisLevel) { + if (state > 0) { + zeroCrossingCount++; + } + state = -1; + } + } + return zeroCrossingCount; +} + +static constexpr int kChannelCount = 1; + +/** + * Convert a sine wave and then look for glitches. + * Glitches have a high value in the second derivative. + */ +static void checkResampler(int32_t sourceRate, int32_t sinkRate, + MultiChannelResampler::Quality quality) { + const int kNumOutputSamples = 10000; + const double framesPerCycle = 81.379; // target output period + + int numInputSamples = kNumOutputSamples * sourceRate / sinkRate; + + std::unique_ptr<float[]> inputBuffer = std::make_unique<float[]>(numInputSamples); + std::unique_ptr<float[]> outputBuffer = std::make_unique<float[]>(kNumOutputSamples); + + // Generate a sine wave for input. + const double kPhaseIncrement = 2.0 * sinkRate / (framesPerCycle * sourceRate); + double phase = 0.0; + for (int i = 0; i < numInputSamples; i++) { + inputBuffer[i] = sin(phase * M_PI); + phase += kPhaseIncrement; + while (phase > 1.0) { + phase -= 2.0; + } + } + int sourceZeroCrossingCount = countZeroCrossingsWithHysteresis(inputBuffer.get(), numInputSamples); + + // Use a MultiChannelResampler to convert from the sourceRate to the sinkRate. + std::unique_ptr<MultiChannelResampler> mcResampler; + mcResampler.reset(MultiChannelResampler::make(kChannelCount, + sourceRate, + sinkRate, + quality)); + int inputFramesLeft = numInputSamples; + int numRead = 0; + float *input = inputBuffer.get(); // for iteration + float *output = outputBuffer.get(); + while (inputFramesLeft > 0) { + if (mcResampler->isWriteNeeded()) { + mcResampler->writeNextFrame(input); + input++; + inputFramesLeft--; + } else { + mcResampler->readNextFrame(output); + output++; + numRead++; + } + } + + // Flush out remaining frames from the flowgraph + while (!mcResampler->isWriteNeeded()) { + mcResampler->readNextFrame(output); + output++; + numRead++; + } + + ASSERT_LE(numRead, kNumOutputSamples); + // Some frames are lost priming the FIR filter. + const int kMaxAlgorithmicFrameLoss = 5; + EXPECT_GT(numRead, kNumOutputSamples - kMaxAlgorithmicFrameLoss); + + int sinkZeroCrossingCount = countZeroCrossingsWithHysteresis(outputBuffer.get(), numRead); + // The sine wave may be cut off partially. This may cause multiple crossing + // differences when upsampling. + const int kMaxZeroCrossingDelta = std::max(sinkRate / sourceRate / 2, 1); + EXPECT_LE(abs(sourceZeroCrossingCount - sinkZeroCrossingCount), kMaxZeroCrossingDelta); + + // Detect glitches by looking for spikes in the second derivative. + output = outputBuffer.get(); + float previousValue = output[0]; + float previousSlope = output[1] - output[0]; + for (int i = 0; i < numRead; i++) { + float slope = output[i] - previousValue; + float slopeDelta = fabs(slope - previousSlope); + // Skip a few samples because there are often some steep slope changes at the beginning. + if (i > 10) { + EXPECT_LT(slopeDelta, 0.1); + } + previousValue = output[i]; + previousSlope = slope; + } + +#if 0 + // Save to disk for inspection. + FILE *fp = fopen( "/sdcard/Download/src_float_out.raw" , "wb" ); + fwrite(outputBuffer.get(), sizeof(float), numRead, fp ); + fclose(fp); +#endif +} + + +TEST(test_resampler, resampler_scan_all) { + const int rates[] = {8000, 11025, 22050, 32000, 44100, 48000, 64000, 88200, 96000}; + const MultiChannelResampler::Quality qualities[] = + { + MultiChannelResampler::Quality::Fastest, + MultiChannelResampler::Quality::Low, + MultiChannelResampler::Quality::Medium, + MultiChannelResampler::Quality::High, + MultiChannelResampler::Quality::Best + }; + for (int srcRate : rates) { + for (int destRate : rates) { + for (auto quality : qualities) { + if (srcRate != destRate) { + checkResampler(srcRate, destRate, quality); + } + } + } + } +} + +TEST(test_resampler, resampler_8000_11025_best) { + checkResampler(8000, 11025, MultiChannelResampler::Quality::Best); +} +TEST(test_resampler, resampler_8000_48000_best) { + checkResampler(8000, 48000, MultiChannelResampler::Quality::Best); +} + +TEST(test_resampler, resampler_8000_44100_best) { + checkResampler(8000, 44100, MultiChannelResampler::Quality::Best); +} + +TEST(test_resampler, resampler_11025_24000_best) { + checkResampler(11025, 24000, MultiChannelResampler::Quality::Best); +} + +TEST(test_resampler, resampler_11025_48000_fastest) { + checkResampler(11025, 48000, MultiChannelResampler::Quality::Fastest); +} +TEST(test_resampler, resampler_11025_48000_low) { + checkResampler(11025, 48000, MultiChannelResampler::Quality::Low); +} +TEST(test_resampler, resampler_11025_48000_medium) { + checkResampler(11025, 48000, MultiChannelResampler::Quality::Medium); +} +TEST(test_resampler, resampler_11025_48000_high) { + checkResampler(11025, 48000, MultiChannelResampler::Quality::High); +} + +TEST(test_resampler, resampler_11025_48000_best) { + checkResampler(11025, 48000, MultiChannelResampler::Quality::Best); +} + +TEST(test_resampler, resampler_11025_44100_best) { + checkResampler(11025, 44100, MultiChannelResampler::Quality::Best); +} + +TEST(test_resampler, resampler_11025_88200_best) { + checkResampler(11025, 88200, MultiChannelResampler::Quality::Best); +} + +TEST(test_resampler, resampler_16000_48000_best) { + checkResampler(16000, 48000, MultiChannelResampler::Quality::Best); +} + +TEST(test_resampler, resampler_44100_48000_low) { + checkResampler(44100, 48000, MultiChannelResampler::Quality::Low); +} +TEST(test_resampler, resampler_44100_48000_best) { + checkResampler(44100, 48000, MultiChannelResampler::Quality::Best); +} + +// Look for glitches when downsampling. +TEST(test_resampler, resampler_48000_11025_best) { + checkResampler(48000, 11025, MultiChannelResampler::Quality::Best); +} +TEST(test_resampler, resampler_48000_44100_best) { + checkResampler(48000, 44100, MultiChannelResampler::Quality::Best); +} +TEST(test_resampler, resampler_44100_11025_best) { + checkResampler(44100, 11025, MultiChannelResampler::Quality::Best); +} |
