PitchDetector Class Reference

A utility class for estimating the pitch (fundamental period) of a given audio signal segment. More...

#include <pitch_detector.h>

Public Member Functions
	PitchDetector ()
	Constructs a PitchDetector with no loaded signal.
void	setSize (int size)
	Sets the internal size of the signal used for pitch detection.
void	loadSignal (const float *signal, int size)
	Loads a signal into the PitchDetector for analysis.
float	getPeriodError (float period)
	Computes the error metric for a given period length.
float	findYinPeriod (int max_period)
	Searches for a period using a YIN-like algorithm, up to a specified maximum period.
float	matchPeriod (int max_period)
	High-level method to find the best matching period using the YIN approach.
const float *	data () const
	Returns a pointer to the internal signal data buffer.

Static Public Attributes
static constexpr int	kNumPoints = 2520
	A fixed number of points used in the period error computation.

Protected Attributes
int	size_
	Number of samples in the loaded signal.
std::unique_ptr< float[]>	signal_data_
	Buffer holding the loaded signal samples.

Detailed Description

A utility class for estimating the pitch (fundamental period) of a given audio signal segment.

The PitchDetector class loads a segment of audio samples and attempts to determine its fundamental period using a variation of the YIN pitch detection algorithm. By estimating the period length that minimizes differences between segments of the waveform, it can guide other components (like wavetable extraction) to align frames to a fundamental cycle.

Constructor & Destructor Documentation

PitchDetector()

PitchDetector::PitchDetector

(

)

Constructs a PitchDetector with no loaded signal.

Member Function Documentation

data()

const float * PitchDetector::data ( ) const

inline

Returns a pointer to the internal signal data buffer.

Returns

A const pointer to the loaded signal samples.

findYinPeriod()

float PitchDetector::findYinPeriod

(

int

max_period

)

Searches for a period using a YIN-like algorithm, up to a specified maximum period.

Evaluates candidate periods and selects the one with minimal error.

Parameters

max_period

The maximum period length to consider, in samples.

Returns

The detected period length in samples.

getPeriodError()

float PitchDetector::getPeriodError

(

float

period

)

Computes the error metric for a given period length.

A lower error typically indicates a more likely fundamental period. This function uses differences between successive segments of the waveform to compute the error.

Parameters

period

The candidate period length in samples.

Returns

An error metric for how well this period fits the waveform.

loadSignal()

void PitchDetector::loadSignal	(	const float *	signal,
		int	size )

Loads a signal into the PitchDetector for analysis.

Copies the given signal into the detector's buffer.

Parameters

signal	Pointer to the signal samples.
size	Number of samples in the signal.

matchPeriod()

float PitchDetector::matchPeriod

(

int

max_period

)

High-level method to find the best matching period using the YIN approach.

Parameters

max_period

The maximum period length to consider.

Returns

The best matching period in samples.

setSize()

void PitchDetector::setSize ( int size )

inline

Sets the internal size of the signal used for pitch detection.

Parameters

size	Number of samples in the loaded signal.

Member Data Documentation

kNumPoints

int PitchDetector::kNumPoints = 2520

staticconstexpr

A fixed number of points used in the period error computation.

This number controls how many sample comparisons are made to estimate the signal's period.

signal_data_

std::unique_ptr<float[]> PitchDetector::signal_data_

protected

Buffer holding the loaded signal samples.

size_

int PitchDetector::size_

protected

Number of samples in the loaded signal.

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

• /Users/davidvogel/repos/VitalHelp/src/common/wavetable/pitch_detector.h
• /Users/davidvogel/repos/VitalHelp/src/common/wavetable/pitch_detector.cpp