Class of functions for auditory preprocessing. More...

#include <auditorypreprocessing.h>

Collaboration diagram for entropyminimizer::AuditoryPreprocessing:

Public Types
using	SpectrumType = Key::SpectrumType

using	Keys = Keyboard::Keys

Public Member Functions
	AuditoryPreprocessing (Piano &piano)
	Constructor. More...

	~AuditoryPreprocessing ()

bool	checkDataConsistency ()
	Check consistency of the piano dataset. More...

void	normalizeSpectrum (Key &key)
	Normalize spectrum. More...

double	getInharmonicPartial (double n, double f1, double B)
	Compute frequency of inharmonic partial. More...

double	getInharmonicPartialIndex (double f, double f1, double B)

void	cleanSpectrum (Key &key)
	Clean logarithmically binned spectrum. More...

void	cutLowFrequencies (Key &key)
	Cut all frequencies below 5/6*f1 in order to reduce noise. More...

void	initializeSPLAFilter ()
	Initialize the filter function in the vector mdBA. More...

void	convertToSPLA (SpectrumType &s)
	Compute A-weighted sound pressure level SPLA. More...

void	convertToLoudness (SpectrumType &s)

void	extrapolateInharmonicity ()
	Extrapolate inharmonicity and estimate missing values. More...

void	improveHighFrequencyPeaks ()
	Improve high-frequency spectral lines. More...

void	applyMollifier (Key &key)

Public Attributes
const size_t	NumberOfBins = Key::NumberOfBins

Static Private Member Functions
static double	ftom (double f)

static double	mtof (int m)

Private Attributes
Piano &	mPiano

Keyboard &	mKeyboard

Keys &	mKeys

int	mNumberOfKeys

int	mKeyNumberOfA4

std::vector< double >	mdBA

Detailed Description

Class of functions for auditory preprocessing.

This class includes functions needed for the preparation of the spectra. It is controlled by the CalculationManager.

Definition at line 41 of file auditorypreprocessing.h.

Member Typedef Documentation

using entropyminimizer::AuditoryPreprocessing::Keys = Keyboard::Keys

Definition at line 48 of file auditorypreprocessing.h.

using entropyminimizer::AuditoryPreprocessing::SpectrumType = Key::SpectrumType

Definition at line 47 of file auditorypreprocessing.h.

Constructor & Destructor Documentation

entropyminimizer::AuditoryPreprocessing::AuditoryPreprocessing ( Piano & piano )

Constructor.

Initializes the member variables.

Definition at line 49 of file auditorypreprocessing.cpp.

entropyminimizer::AuditoryPreprocessing::~AuditoryPreprocessing ( )

inline

Definition at line 45 of file auditorypreprocessing.h.

Member Function Documentation

void entropyminimizer::AuditoryPreprocessing::applyMollifier ( Key & key )

Definition at line 416 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

bool entropyminimizer::AuditoryPreprocessing::checkDataConsistency ( )

Check consistency of the piano dataset.

This function tests the consistency of the incoming Piano dataset.

Returns: true if consistent.

Definition at line 71 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

void entropyminimizer::AuditoryPreprocessing::cleanSpectrum ( Key & key )

Clean logarithmically binned spectrum.

The purpose of this function is to cut away all contributions in the logarithmically binned spectrum which are not close to the location of expected partials (for given ground frequency f1 and inharmonicity B). To this end we define an envelope function in the range [0,1] which exhibits sharp peaks around the low-lying partials and broader peaks for the higher partials. This ensures that possible inaccuracies in the previous determination of the inharmonicity do not load to an errorneous cancellation of higher partials.

Parameters

key	: Reference to the key

Definition at line 230 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

void entropyminimizer::AuditoryPreprocessing::convertToLoudness ( SpectrumType & s )

void entropyminimizer::AuditoryPreprocessing::convertToSPLA ( SpectrumType & spectrum )

Compute A-weighted sound pressure level SPLA.

This function computes the dBA-weighted sound pressure level (SPLA). The SPLA is basically the logarithm of the power of each spectral line with respect to a suitable lower cutoff. For simplicity the SPLA is stored in the same spectrum vector of the local copy, destroying the existing data which is not used for tuning.

Parameters

spectrum : Reference to the spectrum

Definition at line 310 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

void entropyminimizer::AuditoryPreprocessing::cutLowFrequencies ( Key & key )

Cut all frequencies below 5/6*f1 in order to reduce noise.

Parameters

key	: Reference to the key

Definition at line 255 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

void entropyminimizer::AuditoryPreprocessing::extrapolateInharmonicity ( )

Extrapolate inharmonicity and estimate missing values.

In the upper half of the manual, the inharmonicity of the strings of a piano grows typically exponentially with the key index. During recording, however, some of the inharmonicity values are usually not correctly measured. This function identifies the outlyers and replaces them by a suitable interpolated value. Note that this works only with the standard design of pianos (parallel strings of the same kind in the upper half).

Definition at line 340 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

static double entropyminimizer::AuditoryPreprocessing::ftom ( double f )

inlinestaticprivate

Definition at line 71 of file auditorypreprocessing.h.

Here is the call graph for this function:

double entropyminimizer::AuditoryPreprocessing::getInharmonicPartial	(	double	n,
		double	f1,
		double	B
	)

Compute frequency of inharmonic partial.

This is the well-known function \(f_n=f_1 \sqrt{\frac{1+B n^2}{1+B} } \).

Parameters

n	: Number of the partial
f1	: Frequency of the first partial
B	: Inharmonicity coefficient

Returns: Frequency fn

Definition at line 182 of file auditorypreprocessing.cpp.

double entropyminimizer::AuditoryPreprocessing::getInharmonicPartialIndex	(	double	f,
		double	f1,
		double	B
	)

This function is the inverse of the function InharmonicPartialFrequency. It computes the number of the actual partial (as a floating point) for given f, f1, and B. This is an exact inverse function.

Parameters

f	: Frequency of the n+th partial
f1	: Frequency of the first partial
B	: Inharmonicity coefficient

Returns: Number of the actual partial as a floating point

Definition at line 203 of file auditorypreprocessing.cpp.

void entropyminimizer::AuditoryPreprocessing::improveHighFrequencyPeaks ( )

Improve high-frequency spectral lines.

Depending on the microphone the high-frequency spectral lines above 5kHz are sometimes very weak.

Definition at line 384 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

void entropyminimizer::AuditoryPreprocessing::initializeSPLAFilter ( )

Initialize the filter function in the vector mdBA.

Here we use ordinary dBA filtering. The empirical function is given by

\[ _A(f)= {12200^2\cdot f^4\over (f^2+20.6^2) \quad\sqrt{(f^2+107.7^2)\,(f^2+737.9^2)} \quad (f^2+12200^2)}\]

For the sake of efficiency the values according to the logarithmically binned spectra are stored in a vector mdBA.

Definition at line 279 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

static double entropyminimizer::AuditoryPreprocessing::mtof ( int m )

inlinestaticprivate

Definition at line 72 of file auditorypreprocessing.h.

Here is the call graph for this function:

void entropyminimizer::AuditoryPreprocessing::normalizeSpectrum ( Key & key )

Normalize spectrum.

This function normalizes the logarithmic power spectra in such a way that the sum over all components is equal to 1.

Definition at line 160 of file auditorypreprocessing.cpp.

Here is the call graph for this function:

Member Data Documentation

std::vector<double> entropyminimizer::AuditoryPreprocessing::mdBA

private

Definition at line 79 of file auditorypreprocessing.h.

Keyboard& entropyminimizer::AuditoryPreprocessing::mKeyboard

private

Definition at line 75 of file auditorypreprocessing.h.

int entropyminimizer::AuditoryPreprocessing::mKeyNumberOfA4

private

Definition at line 78 of file auditorypreprocessing.h.

Keys& entropyminimizer::AuditoryPreprocessing::mKeys

private

Definition at line 76 of file auditorypreprocessing.h.

int entropyminimizer::AuditoryPreprocessing::mNumberOfKeys

private

Definition at line 77 of file auditorypreprocessing.h.

Piano& entropyminimizer::AuditoryPreprocessing::mPiano

private

Definition at line 74 of file auditorypreprocessing.h.

const size_t entropyminimizer::AuditoryPreprocessing::NumberOfBins = Key::NumberOfBins

Definition at line 49 of file auditorypreprocessing.h.

The documentation for this class was generated from the following files:

/home/hinrichsen/Dokumente/Aktuell/EPT/Entropy-Piano-Tuner/algorithms/entropyminimizer/auditorypreprocessing.h
/home/hinrichsen/Dokumente/Aktuell/EPT/Entropy-Piano-Tuner/algorithms/entropyminimizer/auditorypreprocessing.cpp

Public Types

Public Member Functions

Public Attributes

Static Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation