Shift a signal by a given frequency. More...

#include <frequencyshifter.h>

Public Types
enum	HilbertMode { fir, fft }

Public Member Functions
	FrequencyShifter (const inputSample_t *inputSignal, const std::size_t inputSignalSize, const double sr, HilbertMode mode=HilbertMode::fir)
	Construct a FrequencyShifter, which uses either an FIR or FFT. More...

void	shift (const parameter_t fShift, inputSample_t *shiftedSignal, const std::size_t shiftedSignalSize)
	Shift the input signal by the stated amount and fill shiftedSignal. More...

Protected Attributes
const inputSample_t *	inputSignal
	input signal

const std::size_t	inputSignalSize
	input signal size

std::complex< inputSample_t > *	analyticSignal
	Complex array to store results of Hilbert transform.

const parameter_t	sr
	Sample rate.

Detailed Description

Shift a signal by a given frequency.

Use SSB modulation, implemeted via the Hilbert transform (which is itself implemented with FFTs from the FFTW library).

Definition at line 12 of file frequencyshifter.h.

Member Enumeration Documentation

◆ HilbertMode

enum FrequencyShifter::HilbertMode

Enumerator
fir	FIR.
fft	FFT.

Definition at line 15 of file frequencyshifter.h.

Constructor & Destructor Documentation

◆ FrequencyShifter()

FrequencyShifter::FrequencyShifter	(	const inputSample_t *	inputSignal,
		const std::size_t	inputSignalSize,
		const double	sr,
		HilbertMode	mode = `HilbertMode::fir`
	)

Construct a FrequencyShifter, which uses either an FIR or FFT.

We rely on the float version (low precision) of FFTW3 for all the transforms, and assume inputSample_t to be float. Make the code work for inputSample_t double or long double (e.g. using templates) is not currently supported. Additionally the double-precision version of the FFTW3 library would have to be linked.

Parameters

inputSignal	The signal to be shifted
inputSignalSize	Length of the signal
sr	Sample rate of the audio
mode	FrequencyShifter.fir or FrequencyShifter.fft

Member Function Documentation

◆ shift()

void FrequencyShifter::shift	(	const parameter_t	fShift,
		inputSample_t *	shiftedSignal,
		const std::size_t	shiftedSignalSize
	)

Shift the input signal by the stated amount and fill shiftedSignal.

Parameters

fShift	Frequency by which to shift the signal (Hz)
shiftedSignal	Output buffer
shiftedSignalSize	Length of the output buffer

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

/home/keziah/onsets/DetectorBank/src/frequencyshifter.h

Public Types

Public Member Functions