UTILSLIB::SSS Class Reference

#include <sss.h>

Classes
struct	Basis
	Precomputed SSS basis and projectors for a given sensor array. More...

Public Types
using	Params = SSSParams

Static Public Member Functions
static Basis	computeBasis (const FIFFLIB::FiffInfo &fiffInfo, const Params &params=Params())
static Eigen::MatrixXd	apply (const Eigen::MatrixXd &matData, const Basis &basis)
static Eigen::MatrixXd	applyTemporal (const Eigen::MatrixXd &matData, const Basis &basis, int iBufferLength=10000, double dCorrLimit=0.98)

Detailed Description

Definition at line 110 of file sss.h.

Member Typedef Documentation

Params

using UTILSLIB::SSS::Params = SSSParams

Convenience alias so callers can still write SSS::Params.

Definition at line 113 of file sss.h.

Member Function Documentation

apply()

MatrixXd SSS::apply ( const Eigen::MatrixXd & matData, const Basis & basis )

static

Apply SSS to MEG data — suppress external (environmental) interference.

Parameters

[in]	matData	Full sensor data (n_channels × n_samples). Non-MEG channels are passed through unchanged.
[in]	basis	Precomputed basis from computeBasis().

Returns

SSS-cleaned data (n_channels × n_samples).

Definition at line 424 of file sss.cpp.

applyTemporal()

MatrixXd SSS::applyTemporal ( const Eigen::MatrixXd & matData, const Basis & basis, int iBufferLength = 10000, double dCorrLimit = 0.98 )

static

Apply temporal SSS (tSSS) — additionally suppress near-field artefacts.

tSSS processes the data in sliding windows and removes the temporal subspace of the external expansion that exceeds dCorrLimit (relative to the dominant singular value).

Parameters

[in]	matData	Full sensor data (n_channels × n_samples).
[in]	basis	Precomputed basis from computeBasis().
[in]	iBufferLength	Window length in samples (default 10000 ≈ 10 s at 1 kHz).
[in]	dCorrLimit	Correlation threshold [0, 1]; singular vectors of the external subspace whose normalised value exceeds this are removed from the internal expansion (default 0.98).

Returns

tSSS-cleaned data (n_channels × n_samples).

Definition at line 452 of file sss.cpp.

computeBasis()

SSS::Basis SSS::computeBasis ( const FIFFLIB::FiffInfo & fiffInfo, const Params & params = Params() )

static

Build the SSS spherical-harmonic basis from MEG sensor geometry.

Only channels with kind == FIFFV_MEG_CH or FIFFV_REF_MEG_CH are used. Sensor positions and normals are taken from FiffChInfo::chpos (coil-centre single-point model).

Parameters

[in]	fiffInfo	Measurement info containing channel positions.
[in]	params	SSS configuration (order, origin, regularisation).

Returns

Basis struct containing all projectors needed for SSS and tSSS.

Definition at line 301 of file sss.cpp.

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

• src/libraries/dsp/sss.h
• src/libraries/dsp/sss.cpp