A spatially-localised active-intensity (SLAI) based direction-of- arrival estimator (SLDoA) More...

#include "sldoa.h"
#include "saf.h"
#include "saf_externals.h"

Data Structures
struct	sldoa_data
	Main struct for sldoa. More...

Macros
#define	SLDOA_FRAME_SIZE ( 512 )
	Framesize, in time-domain samples.

#define	ORDER2NUMSECTORS(L) ( L*L )
	Macro to convert SH order to number of sectors.

#define	HOP_SIZE ( 128 )
	STFT hop size.

#define	HYBRID_BANDS ( HOP_SIZE + 5 )
	hybrid mode incurs an additional 5 bands

#define	TIME_SLOTS ( SLDOA_FRAME_SIZE / HOP_SIZE )
	Processing relies on fdHop = 16.

#define	MAX_NUM_SECTORS ( 64 )
	maximum number of sectors, TODO: expand beyond 64 (which is the max possible in the spherecovering grids we currently use)

#define	NUM_DISP_SLOTS ( 2 )
	Number of display slots; needs to be at least 2.

Functions
void	sldoa_setCodecStatus (void *const hSld, CODEC_STATUS newStatus)
	Sets codec status (see CODEC_STATUS enum)

void	sldoa_initAna (void *const hSld)
	Intialises the codec variables, based on current global/user parameters.

void	sldoa_initTFT (void *const hSld)
	Initialise the filterbank used by sldoa.

void	sldoa_estimateDoA (float_complex *SHframeTF, int anaOrder, float_complex secCoeffs, float doa[MAX_NUM_SECTORS][TIME_SLOTS][2], float energy[MAX_NUM_SECTORS][TIME_SLOTS])
	Estimates the DoA using the active intensity vectors derived from spatially localised sectors, as in [1,2].

Detailed Description

A spatially-localised active-intensity (SLAI) based direction-of- arrival estimator (SLDoA)

VBAP gain patterns are imposed on the spherical harmonic signals, such that the DoA can be estimated in a spatially-constrained region; thus mitigating the effect of interferes and reflections arriving from other directions. The DoA is estimated per sector for each frequency band.

The algorithms within sldoa were developed in collaboration with Symeon Delikaris-Manias and Angelo Farina, and are explained in more detail in [1,2]

See also: [1] McCormack, L., Delikaris-Manias, S., Politis, A., Pavlidi, D., Farina, A., Pinardi, D. and Pulkki, V., 2019. Applications of Spatially Localized Active-Intensity Vectors for Sound-Field Visualization. Journal of the Audio Engineering Society, 67(11), pp.840-854.; [2] McCormack, L., Delikaris-Manias, S., Farina, A., Pinardi, D., and Pulkki, V., "Real-time conversion of sensor array signals into spherical harmonic signals with applications to spatially localised sub-band sound-field analysis," in Audio Engineering Society Convention 144, Audio Engineering Society, 2018.

Author: Leo McCormack

Date: 18.10.2017

License: ISC

Definition in file sldoa_internal.h.

Macro Definition Documentation

◆ HOP_SIZE

#define HOP_SIZE ( 128 )

STFT hop size.

Definition at line 69 of file sldoa_internal.h.

◆ HYBRID_BANDS

#define HYBRID_BANDS ( HOP_SIZE + 5 )

hybrid mode incurs an additional 5 bands

Definition at line 70 of file sldoa_internal.h.

◆ MAX_NUM_SECTORS

#define MAX_NUM_SECTORS ( 64 )

maximum number of sectors, TODO: expand beyond 64 (which is the max possible in the spherecovering grids we currently use)

Definition at line 72 of file sldoa_internal.h.

◆ NUM_DISP_SLOTS

#define NUM_DISP_SLOTS ( 2 )

Number of display slots; needs to be at least 2.

On slower systems that skip frames, consider adding more slots.

Definition at line 73 of file sldoa_internal.h.

◆ ORDER2NUMSECTORS

#define ORDER2NUMSECTORS ( L ) ( L*L )

Macro to convert SH order to number of sectors.

Definition at line 68 of file sldoa_internal.h.

◆ SLDOA_FRAME_SIZE

#define SLDOA_FRAME_SIZE ( 512 )

Framesize, in time-domain samples.

Definition at line 65 of file sldoa_internal.h.

◆ TIME_SLOTS

#define TIME_SLOTS ( SLDOA_FRAME_SIZE / HOP_SIZE )

Processing relies on fdHop = 16.

Definition at line 71 of file sldoa_internal.h.

Function Documentation

◆ sldoa_estimateDoA()

void sldoa_estimateDoA	(	float_complex **	SHframeTF,
		int	anaOrder,
		float_complex *	secCoeffs,
		float	doa[MAX_NUM_SECTORS][TIME_SLOTS][2],
		float	energy[MAX_NUM_SECTORS][TIME_SLOTS] )

Estimates the DoA using the active intensity vectors derived from spatially localised sectors, as in [1,2].

Note: If anaOrder is 1, then the algorithm reverts to the standard active- intensity based DoA estimation.

Parameters

[in]	SHframeTF	Input SH frame; MAX_NUM_SH_SIGNALS x TIME_SLOTS
[in]	anaOrder	Analysis order (1:AI, 2+: SLAI)
[in]	secCoeffs	Sector coefficients for this order
[out]	doa	Resulting DoA estimates per timeslot and sector
[out]	energy	Resulting sector energies per time slot

See also: [1] McCormack, L., Delikaris-Manias, S., Farina, A., Pinardi, D., and Pulkki, V., “Real-time conversion of sensor array signals into spherical harmonic signals with applications to spatially localised sub-band sound-field analysis,” in Audio Engineering Society Convention 144, Audio Engineering Society, 2018.; [2] McCormack, L., Delikaris-Manias, S., Politis, A., Pavlidi, D., Farina, A., Pinardi, D. and Pulkki, V., 2019. Applications of Spatially Localized Active-Intensity Vectors for Sound-Field Visualization. Journal of the Audio Engineering Society, 67(11), pp.840-854.

Definition at line 145 of file sldoa_internal.c.

◆ sldoa_initAna()

void sldoa_initAna ( void *const hSld )

Intialises the codec variables, based on current global/user parameters.

The formulae for calculating the sector coefficients can be found in [1,2].

See also: [1] McCormack, L., Delikaris-Manias, S., Farina, A., Pinardi, D., and Pulkki, V., “Real-time conversion of sensor array signals into spherical harmonic signals with applications to spatially localised sub-band sound-field analysis,” in Audio Engineering Society Convention 144, Audio Engineering Society, 2018.; [2] McCormack, L., Delikaris-Manias, S., Politis, A., Pavlidi, D., Farina, A., Pinardi, D. and Pulkki, V., 2019. Applications of Spatially Localized Active-Intensity Vectors for Sound-Field Visualization. Journal of the Audio Engineering Society, 67(11), pp.840-854.

Definition at line 60 of file sldoa_internal.c.

◆ sldoa_initTFT()

void sldoa_initTFT ( void *const hSld )

Initialise the filterbank used by sldoa.

Note: Call this function before sldoa_initAna()

Input Arguments: hSld - sldoa handle

Definition at line 127 of file sldoa_internal.c.

◆ sldoa_setCodecStatus()

void sldoa_setCodecStatus	(	void *const	hSld,
		CODEC_STATUS	newStatus )

Sets codec status (see CODEC_STATUS enum)

Definition at line 49 of file sldoa_internal.c.

Data Structures

Macros

Functions