Class for calculating BPM rate for audio data. More...

#include <BPMDetect.h>

Public Member Functions
	BPMDetect (int numChannels, int sampleRate)
	Constructor.
virtual	~BPMDetect ()
	Destructor.
void	inputSamples (soundtouch::SAMPLETYPE *samples, int numSamples)
	Inputs a block of samples for analyzing: Envelopes the samples and then updates the autocorrelation estimation.
float	getBpm ()
	Analyzes the results and returns the BPM rate.
Protected Member Functions
void	init (int numChannels, int sampleRate)
	Initialize the class for processing.
void	updateXCorr (int process_samples)
	Updates auto-correlation function for given number of decimated samples that are read from the internal 'buffer' pipe (samples aren't removed from the pipe though).
int	decimate (soundtouch::SAMPLETYPE dest, const soundtouch::SAMPLETYPE src, int numsamples)
	Decimates samples to approx.
void	calcEnvelope (soundtouch::SAMPLETYPE *samples, int numsamples)
	Calculates amplitude envelope for the buffer of samples.
Protected Attributes
float *	xcorr
	Auto-correlation accumulator bins.
float	envelopeAccu
	Amplitude envelope sliding average approximation level accumulator.
float	RMSVolumeAccu
	RMS volume sliding average approximation level accumulator.
int	decimateCount
	Sample average counter.
soundtouch::LONG_SAMPLETYPE	decimateSum
	Sample average accumulator for FIFO-like decimation.
int	decimateBy
	Decimate sound by this coefficient to reach approx. 500 Hz.
int	windowLen
	Auto-correlation window length.
int	channels
	Number of channels (1 = mono, 2 = stereo)
int	sampleRate
	sample rate
int	windowStart
	Beginning of auto-correlation window: Autocorrelation isn't being updated for the first these many correlation bins.
soundtouch::FIFOSampleBuffer *	buffer
	FIFO-buffer for decimated processing samples.

Detailed Description

Class for calculating BPM rate for audio data.

Definition at line 71 of file BPMDetect.h.

Constructor & Destructor Documentation

BPMDetect::BPMDetect	(	int	numChannels,
		int	sampleRate
	)

Constructor.

Parameters:

numChannels	Number of channels in sample data.
sampleRate	Sample rate in Hz.

virtual BPMDetect::~BPMDetect ( ) [virtual]

Destructor.

Member Function Documentation

void BPMDetect::init	(	int	numChannels,
		int	sampleRate
	)		`[protected]`

Initialize the class for processing.

void BPMDetect::updateXCorr ( int process_samples ) [protected]

Updates auto-correlation function for given number of decimated samples that are read from the internal 'buffer' pipe (samples aren't removed from the pipe though).

Parameters:

process_samples How many samples are processed.