phasevoc.h File Reference

Phase vocoder object. More...

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Typedefs
typedef _aubio_pvoc_t	aubio_pvoc_t
	phasevocoder object
Functions
aubio_pvoc_t *	new_aubio_pvoc (uint_t win_s, uint_t hop_s, uint_t channels)
	create phase vocoder object
void	del_aubio_pvoc (aubio_pvoc_t *pv)
	delete phase vocoder object
void	aubio_pvoc_do (aubio_pvoc_t *pv, fvec_t *in, cvec_t *fftgrain)
	compute spectral frame
void	aubio_pvoc_rdo (aubio_pvoc_t *pv, cvec_t *fftgrain, fvec_t *out)
	compute signal from spectral frame
uint_t	aubio_pvoc_get_win (aubio_pvoc_t *pv)
	get window size
uint_t	aubio_pvoc_get_hop (aubio_pvoc_t *pv)
	get hop size
uint_t	aubio_pvoc_get_channels (aubio_pvoc_t *pv)
	get channel number

---

Detailed Description

Phase vocoder object.

This object implements a phase vocoder. The spectral frames are computed using a HanningZ window and a swapped version of the signal to simplify the phase relationships across frames. The window sizes and overlap are specified at creation time. Multiple channels are fully supported.

---

Function Documentation

void aubio_pvoc_do	(	aubio_pvoc_t *	pv,
		fvec_t *	in,
		cvec_t *	fftgrain
	)

compute spectral frame

This function accepts an input vector of size [channels]x[hop_s]. The analysis buffer is rotated and filled with the new data. After windowing of this signal window, the Fourier transform is computed and returned in fftgrain as two vectors, magnitude and phase.

Parameters:

	pv	phase vocoder object as returned by new_aubio_pvoc
	in	new input signal (hop_s long)
	fftgrain	output spectral frame

uint_t aubio_pvoc_get_channels

(

aubio_pvoc_t *

pv

)

get channel number

Parameters:

pv

phase vocoder to get the number of channels from

uint_t aubio_pvoc_get_hop

(

aubio_pvoc_t *

pv

)

get hop size

Parameters:

pv

phase vocoder to get the hop size from

uint_t aubio_pvoc_get_win

(

aubio_pvoc_t *

pv

)

get window size

Parameters:

pv

phase vocoder to get the window size from

void aubio_pvoc_rdo	(	aubio_pvoc_t *	pv,
		cvec_t *	fftgrain,
		fvec_t *	out
	)

compute signal from spectral frame

This function takes an input spectral frame fftgrain of size [channels]x[buf_s] and computes its inverse Fourier transform. Overlap-add synthesis is then computed using the previously synthetised frames, and the output stored in out.

Parameters:

	pv	phase vocoder object as returned by new_aubio_pvoc
	fftgrain	input spectral frame
	out	output signal (hop_s long)

void del_aubio_pvoc

(

aubio_pvoc_t *

pv

)

delete phase vocoder object

Parameters:

pv

phase vocoder object as returned by new_aubio_pvoc

aubio_pvoc_t* new_aubio_pvoc	(	uint_t	win_s,
		uint_t	hop_s,
		uint_t	channels
	)

create phase vocoder object

Parameters:

	win_s	size of analysis buffer (and length the FFT transform)
	hop_s	step size between two consecutive analysis
	channels	number of channels

---