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-rw-r--r--source/application/main/Mfcc.cc126
1 files changed, 63 insertions, 63 deletions
diff --git a/source/application/main/Mfcc.cc b/source/application/main/Mfcc.cc
index c8ad138..c998ef2 100644
--- a/source/application/main/Mfcc.cc
+++ b/source/application/main/Mfcc.cc
@@ -64,27 +64,27 @@ namespace audio {
}
MFCC::MFCC(const MfccParams& params):
- _m_params(params),
- _m_filterBankInitialised(false)
+ m_params(params),
+ m_filterBankInitialised(false)
{
- this->_m_buffer = std::vector<float>(
- this->_m_params.m_frameLenPadded, 0.0);
- this->_m_frame = std::vector<float>(
- this->_m_params.m_frameLenPadded, 0.0);
- this->_m_melEnergies = std::vector<float>(
- this->_m_params.m_numFbankBins, 0.0);
+ this->m_buffer = std::vector<float>(
+ this->m_params.m_frameLenPadded, 0.0);
+ this->m_frame = std::vector<float>(
+ this->m_params.m_frameLenPadded, 0.0);
+ this->m_melEnergies = std::vector<float>(
+ this->m_params.m_numFbankBins, 0.0);
- this->_m_windowFunc = std::vector<float>(this->_m_params.m_frameLen);
- const auto multiplier = static_cast<float>(2 * M_PI / this->_m_params.m_frameLen);
+ this->m_windowFunc = std::vector<float>(this->m_params.m_frameLen);
+ const auto multiplier = static_cast<float>(2 * M_PI / this->m_params.m_frameLen);
/* Create window function. */
- for (size_t i = 0; i < this->_m_params.m_frameLen; i++) {
- this->_m_windowFunc[i] = (0.5 - (0.5 *
+ for (size_t i = 0; i < this->m_params.m_frameLen; i++) {
+ this->m_windowFunc[i] = (0.5 - (0.5 *
math::MathUtils::CosineF32(static_cast<float>(i) * multiplier)));
}
- math::MathUtils::FftInitF32(this->_m_params.m_frameLenPadded, this->_m_fftInstance);
- debug("Instantiated MFCC object: %s\n", this->_m_params.Str().c_str());
+ math::MathUtils::FftInitF32(this->m_params.m_frameLenPadded, this->m_fftInstance);
+ debug("Instantiated MFCC object: %s\n", this->m_params.Str().c_str());
}
void MFCC::Init()
@@ -166,20 +166,20 @@ namespace audio {
void MFCC::ConvertToPowerSpectrum()
{
- const uint32_t halfDim = this->_m_buffer.size() / 2;
+ const uint32_t halfDim = this->m_buffer.size() / 2;
/* Handle this special case. */
- float firstEnergy = this->_m_buffer[0] * this->_m_buffer[0];
- float lastEnergy = this->_m_buffer[1] * this->_m_buffer[1];
+ float firstEnergy = this->m_buffer[0] * this->m_buffer[0];
+ float lastEnergy = this->m_buffer[1] * this->m_buffer[1];
math::MathUtils::ComplexMagnitudeSquaredF32(
- this->_m_buffer.data(),
- this->_m_buffer.size(),
- this->_m_buffer.data(),
- this->_m_buffer.size()/2);
+ this->m_buffer.data(),
+ this->m_buffer.size(),
+ this->m_buffer.data(),
+ this->m_buffer.size()/2);
- this->_m_buffer[0] = firstEnergy;
- this->_m_buffer[halfDim] = lastEnergy;
+ this->m_buffer[0] = firstEnergy;
+ this->m_buffer[halfDim] = lastEnergy;
}
std::vector<float> MFCC::CreateDCTMatrix(
@@ -219,17 +219,17 @@ namespace audio {
void MFCC::InitMelFilterBank()
{
if (!this->IsMelFilterBankInited()) {
- this->_m_melFilterBank = this->CreateMelFilterBank();
- this->_m_dctMatrix = this->CreateDCTMatrix(
- this->_m_params.m_numFbankBins,
- this->_m_params.m_numMfccFeatures);
- this->_m_filterBankInitialised = true;
+ this->m_melFilterBank = this->CreateMelFilterBank();
+ this->m_dctMatrix = this->CreateDCTMatrix(
+ this->m_params.m_numFbankBins,
+ this->m_params.m_numMfccFeatures);
+ this->m_filterBankInitialised = true;
}
}
bool MFCC::IsMelFilterBankInited() const
{
- return this->_m_filterBankInitialised;
+ return this->m_filterBankInitialised;
}
void MFCC::MfccComputePreFeature(const std::vector<int16_t>& audioData)
@@ -238,78 +238,78 @@ namespace audio {
/* TensorFlow way of normalizing .wav data to (-1, 1). */
constexpr float normaliser = 1.0/(1u<<15u);
- for (size_t i = 0; i < this->_m_params.m_frameLen; i++) {
- this->_m_frame[i] = static_cast<float>(audioData[i]) * normaliser;
+ for (size_t i = 0; i < this->m_params.m_frameLen; i++) {
+ this->m_frame[i] = static_cast<float>(audioData[i]) * normaliser;
}
/* Apply window function to input frame. */
- for(size_t i = 0; i < this->_m_params.m_frameLen; i++) {
- this->_m_frame[i] *= this->_m_windowFunc[i];
+ for(size_t i = 0; i < this->m_params.m_frameLen; i++) {
+ this->m_frame[i] *= this->m_windowFunc[i];
}
/* Set remaining frame values to 0. */
- std::fill(this->_m_frame.begin() + this->_m_params.m_frameLen,this->_m_frame.end(), 0);
+ std::fill(this->m_frame.begin() + this->m_params.m_frameLen,this->m_frame.end(), 0);
/* Compute FFT. */
- math::MathUtils::FftF32(this->_m_frame, this->_m_buffer, this->_m_fftInstance);
+ math::MathUtils::FftF32(this->m_frame, this->m_buffer, this->m_fftInstance);
/* Convert to power spectrum. */
this->ConvertToPowerSpectrum();
/* Apply mel filterbanks. */
- if (!this->ApplyMelFilterBank(this->_m_buffer,
- this->_m_melFilterBank,
- this->_m_filterBankFilterFirst,
- this->_m_filterBankFilterLast,
- this->_m_melEnergies)) {
+ if (!this->ApplyMelFilterBank(this->m_buffer,
+ this->m_melFilterBank,
+ this->m_filterBankFilterFirst,
+ this->m_filterBankFilterLast,
+ this->m_melEnergies)) {
printf_err("Failed to apply MEL filter banks\n");
}
/* Convert to logarithmic scale. */
- this->ConvertToLogarithmicScale(this->_m_melEnergies);
+ this->ConvertToLogarithmicScale(this->m_melEnergies);
}
std::vector<float> MFCC::MfccCompute(const std::vector<int16_t>& audioData)
{
this->MfccComputePreFeature(audioData);
- std::vector<float> mfccOut(this->_m_params.m_numMfccFeatures);
+ std::vector<float> mfccOut(this->m_params.m_numMfccFeatures);
- float * ptrMel = this->_m_melEnergies.data();
- float * ptrDct = this->_m_dctMatrix.data();
+ float * ptrMel = this->m_melEnergies.data();
+ float * ptrDct = this->m_dctMatrix.data();
float * ptrMfcc = mfccOut.data();
/* Take DCT. Uses matrix mul. */
for (size_t i = 0, j = 0; i < mfccOut.size();
- ++i, j += this->_m_params.m_numFbankBins) {
+ ++i, j += this->m_params.m_numFbankBins) {
*ptrMfcc++ = math::MathUtils::DotProductF32(
ptrDct + j,
ptrMel,
- this->_m_params.m_numFbankBins);
+ this->m_params.m_numFbankBins);
}
return mfccOut;
}
std::vector<std::vector<float>> MFCC::CreateMelFilterBank()
{
- size_t numFftBins = this->_m_params.m_frameLenPadded / 2;
- float fftBinWidth = static_cast<float>(this->_m_params.m_samplingFreq) / this->_m_params.m_frameLenPadded;
+ size_t numFftBins = this->m_params.m_frameLenPadded / 2;
+ float fftBinWidth = static_cast<float>(this->m_params.m_samplingFreq) / this->m_params.m_frameLenPadded;
- float melLowFreq = MFCC::MelScale(this->_m_params.m_melLoFreq,
- this->_m_params.m_useHtkMethod);
- float melHighFreq = MFCC::MelScale(this->_m_params.m_melHiFreq,
- this->_m_params.m_useHtkMethod);
- float melFreqDelta = (melHighFreq - melLowFreq) / (this->_m_params.m_numFbankBins + 1);
+ float melLowFreq = MFCC::MelScale(this->m_params.m_melLoFreq,
+ this->m_params.m_useHtkMethod);
+ float melHighFreq = MFCC::MelScale(this->m_params.m_melHiFreq,
+ this->m_params.m_useHtkMethod);
+ float melFreqDelta = (melHighFreq - melLowFreq) / (this->m_params.m_numFbankBins + 1);
std::vector<float> thisBin = std::vector<float>(numFftBins);
std::vector<std::vector<float>> melFilterBank(
- this->_m_params.m_numFbankBins);
- this->_m_filterBankFilterFirst =
- std::vector<uint32_t>(this->_m_params.m_numFbankBins);
- this->_m_filterBankFilterLast =
- std::vector<uint32_t>(this->_m_params.m_numFbankBins);
+ this->m_params.m_numFbankBins);
+ this->m_filterBankFilterFirst =
+ std::vector<uint32_t>(this->m_params.m_numFbankBins);
+ this->m_filterBankFilterLast =
+ std::vector<uint32_t>(this->m_params.m_numFbankBins);
- for (size_t bin = 0; bin < this->_m_params.m_numFbankBins; bin++) {
+ for (size_t bin = 0; bin < this->m_params.m_numFbankBins; bin++) {
float leftMel = melLowFreq + bin * melFreqDelta;
float centerMel = melLowFreq + (bin + 1) * melFreqDelta;
float rightMel = melLowFreq + (bin + 2) * melFreqDelta;
@@ -317,11 +317,11 @@ namespace audio {
uint32_t firstIndex = 0;
uint32_t lastIndex = 0;
bool firstIndexFound = false;
- const float normaliser = this->GetMelFilterBankNormaliser(leftMel, rightMel, this->_m_params.m_useHtkMethod);
+ const float normaliser = this->GetMelFilterBankNormaliser(leftMel, rightMel, this->m_params.m_useHtkMethod);
for (size_t i = 0; i < numFftBins; i++) {
float freq = (fftBinWidth * i); /* Center freq of this fft bin. */
- float mel = MFCC::MelScale(freq, this->_m_params.m_useHtkMethod);
+ float mel = MFCC::MelScale(freq, this->m_params.m_useHtkMethod);
thisBin[i] = 0.0;
if (mel > leftMel && mel < rightMel) {
@@ -341,8 +341,8 @@ namespace audio {
}
}
- this->_m_filterBankFilterFirst[bin] = firstIndex;
- this->_m_filterBankFilterLast[bin] = lastIndex;
+ this->m_filterBankFilterFirst[bin] = firstIndex;
+ this->m_filterBankFilterLast[bin] = lastIndex;
/* Copy the part we care about. */
for (uint32_t i = firstIndex; i <= lastIndex; i++) {
generated by cgit v1.2.1 (git 2.23.0) at 2024-06-01 00:29:19 +0000