Wavelet Filters [Filtering]

Collaboration diagram for Wavelet Filters:

Data Structures
struct	WaveletParameters
	parameters for wavelet-filtering. More...
Typedefs
typedef double *(*	SignalExtensionFunction )(double *, int, int)
	function for extending the signal
typedef double(*	ThresholdFunction )(double, double)
	function for thresholding.
typedef double(*	ThresholdSelectionFunction )(const double *, int)
	function for threshold selection.
Functions
double	conventional_thresholding (const double *data, int n)
	Wavelet estimation of single trial ERP's using a conventional estimate.
double	hard_thresholding (double d, double lambda)
	hard-thresholding.
double	heuristic_sure (const double *data, int n)
	thresholding as proposed in the Matlab Wavelet-Toolbox.
double	soft_thresholding (double d, double lambda)
	soft-thresholding.
double	sureshrink (const double *data, int n)
	procedure described in Donoho et al., 1995.
double	translation_invariant_thresholding (const double *data, int n)
	Wavelet estimation of single trial ERP's using Wang et al.'s (2007) technique.
int	wavelet_denoise (double *data, int n, WaveletParameters P)
	Generic Wavelet-Denoising.
int	wavelet_extend_and_denoise (double *data, int n, WaveletParameters P)
	Extend data to length 2^j using sigextfct and denoise it.
WaveletParameters	wavelet_init ()
	set default parameters for a waveletParameters struct.

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Detailed Description

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Typedef Documentation

typedef double*(* SignalExtensionFunction)(double *, int, int)

function for extending the signal

Definition at line 109 of file wavelet.h.

typedef double(* ThresholdFunction)(double, double)

function for thresholding.

Definition at line 104 of file wavelet.h.

typedef double(* ThresholdSelectionFunction)(const double *, int)

function for threshold selection.

Definition at line 99 of file wavelet.h.

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Function Documentation

double conventional_thresholding	(	const double *	data,
		int	n
	)

Wavelet estimation of single trial ERP's using a conventional estimate.

Formula

.

Definition at line 54 of file wavelet.c.

double hard_thresholding	(	double	d,
		double	lambda
	)

hard-thresholding.

Formula:

Definition at line 226 of file wavelet.c.

double heuristic_sure	(	const double *	data,
		int	n
	)

thresholding as proposed in the Matlab Wavelet-Toolbox.

       case 'heursure' 
         hthr = sqrt(2*log(n)); 
         eta = (norm(x).^2-n)/n; 
         crit = (log(n)/log(2))^(1.5)/sqrt(n); 
         if eta < crit 
             thr = hthr; 
         else 
             thr = min(thselect(x,'rigrsure'),hthr); 
         end 

Definition at line 78 of file wavelet.c.

double soft_thresholding	(	double	d,
		double	lambda
	)

soft-thresholding.

Formula:

Definition at line 209 of file wavelet.c.

double sureshrink	(	const double *	data,
		int	n
	)

procedure described in Donoho et al., 1995.

Definition at line 94 of file wavelet.c.

double translation_invariant_thresholding	(	const double *	data,
		int	n
	)

Wavelet estimation of single trial ERP's using Wang et al.'s (2007) technique.

Formula

.

Definition at line 40 of file wavelet.c.

int wavelet_denoise	(	double *	data,
		int	n,
		WaveletParameters	P
	)

Generic Wavelet-Denoising.

compute DWT of signal, call the thresholding function 'threshfct' for each resolution level and IDWT the signal

Definition at line 133 of file wavelet.c.

int wavelet_extend_and_denoise	(	double *	data,
		int	n,
		WaveletParameters	P
	)

Extend data to length 2^j using sigextfct and denoise it.

See also:

generic_denoising()

Definition at line 184 of file wavelet.c.

WaveletParameters wavelet_init

(

)

set default parameters for a waveletParameters struct.

Definition at line 168 of file wavelet.c.