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Internal change

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PiperOrigin-RevId: 544663494
This commit is contained in:
MediaPipe Team 2023-06-30 08:31:37 -07:00 committed by Copybara-Service
parent 6c7aa8a0d6
commit 422556c4a3
2 changed files with 25 additions and 22 deletions
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45
mediapipe/calculators/audio/spectrogram_calculator.cc
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@ -210,6 +210,23 @@ REGISTER_CALCULATOR(SpectrogramCalculator);
// Factor to convert ln(SQUARED_MAGNITUDE) to deciBels = 10.0/ln(10.0).
const float SpectrogramCalculator::kLnSquaredMagnitudeToDb = 4.342944819032518;
namespace {
std::unique_ptr<audio_dsp::WindowFunction> MakeWindowFun(
const SpectrogramCalculatorOptions::WindowType window_type) {
switch (window_type) {
// The cosine window and square root of Hann are equivalent.
case SpectrogramCalculatorOptions::COSINE:
case SpectrogramCalculatorOptions::SQRT_HANN:
return std::make_unique<audio_dsp::CosineWindow>();
case SpectrogramCalculatorOptions::HANN:
return std::make_unique<audio_dsp::HannWindow>();
case SpectrogramCalculatorOptions::HAMMING:
return std::make_unique<audio_dsp::HammingWindow>();
}
return nullptr;
}
} // namespace
absl::Status SpectrogramCalculator::Open(CalculatorContext* cc) {
SpectrogramCalculatorOptions spectrogram_options =
cc->Options<SpectrogramCalculatorOptions>();
@ -266,28 +283,14 @@ absl::Status SpectrogramCalculator::Open(CalculatorContext* cc) {
output_scale_ = spectrogram_options.output_scale();
std::vector<double> window;
switch (spectrogram_options.window_type()) {
case SpectrogramCalculatorOptions::COSINE:
audio_dsp::CosineWindow().GetPeriodicSamples(frame_duration_samples_,
&window);
break;
case SpectrogramCalculatorOptions::HANN:
audio_dsp::HannWindow().GetPeriodicSamples(frame_duration_samples_,
&window);
break;
case SpectrogramCalculatorOptions::HAMMING:
audio_dsp::HammingWindow().GetPeriodicSamples(frame_duration_samples_,
&window);
break;
case SpectrogramCalculatorOptions::SQRT_HANN: {
audio_dsp::HannWindow().GetPeriodicSamples(frame_duration_samples_,
&window);
absl::c_transform(window, window.begin(),
[](double x) { return std::sqrt(x); });
break;
}
auto window_fun = MakeWindowFun(spectrogram_options.window_type());
if (window_fun == nullptr) {
return absl::Status(absl::StatusCode::kInvalidArgument,
absl::StrCat("Invalid window type ",
spectrogram_options.window_type()));
}
std::vector<double> window;
window_fun->GetPeriodicSamples(frame_duration_samples_, &window);
// Propagate settings down to the actual Spectrogram object.
spectrogram_generators_.clear();

2
mediapipe/calculators/audio/spectrogram_calculator.proto
View File

@ -68,7 +68,7 @@ message SpectrogramCalculatorOptions {
HANN = 0;
HAMMING = 1;
COSINE = 2;
SQRT_HANN = 4;
SQRT_HANN = 4; // Alias of COSINE.
}
optional WindowType window_type = 6 [default = HANN];