Features Class Reference

This class provides the calculations of single-signal features, computed from a single channel with length BLOCKSIZE. More...

#include <conndetect_features.h>

Public Member Functions
	Features (const float fs)
	Create features instance. More...
void	setChannel (const Channel &channel)
	Set channel data to operate on. BORROWS the data on which it operates, be carefull not to delete the underlying Channel! More...
float	peak_dB ()
	Compute the peak level in dB (full scale, normalized to 1). The equation is: More...
float	rms_dB ()
	Compute the rms level in dB (full scale, normalized to 1). The equation is: More...
float	kurtosis ()
	Compute the kurtosis \( K \), scaled. It is defined as: More...
float	peak_freq ()
	Compute the frequency at which the spectrum has the most power. It is defined as: More...
float	wamp (float wampl)
	Willson amplitude. Counts the number of difss in amplitude that have an absolute change in value larger than wampl;. More...
float	zc (float zc_l)
	Compute zero-crossings with a difference larger than zcl. More...
float	TM3 ()
	Temporal moment 3, defined as. More...
float	TM5 ()
	Temporal moment 5, defined as. More...
float	inverse_variance ()
	Inverse of the variance in the center frequency, defined as: More...

Detailed Description

This class provides the calculations of single-signal features, computed from a single channel with length BLOCKSIZE.

Definition at line 18 of file conndetect_features.h.

Constructor & Destructor Documentation

Features()

Features::Features

(

const float

fs

)

Create features instance.

Parameters

fs	Sampling frequency in [Hz]

Definition at line 31 of file conndetect_features.cpp.

Member Function Documentation

inverse_variance()

float Features::inverse_variance

(

)

Inverse of the variance in the center frequency, defined as:

\( IVCF = \frac{f_c^2 \sum \mathrm{abs}(\hat{S}[i])}{\sum \mathrm{abs}(\hat{S}[i]) (f_i - f_c)^2} \)

where

\( f_i = \frac{\sum f_i \mathrm{abs}(\hat{S}[i])}{\sum \mathrm{abs}(\hat{S}[i])}\)

Returns

\( IVCF \)

Definition at line 179 of file conndetect_features.cpp.

kurtosis()

float Features::kurtosis

(

)

Compute the kurtosis \( K \), scaled. It is defined as:

\( K = \frac{1/N\sum_{i=0}^{N-1}(s[i])^4}{\left(1/N\sum_{i=0}^{N-1} (s[i])^2\right)^2} \)

Returns

\( K \)

Definition at line 70 of file conndetect_features.cpp.

peak_dB()

float Features::peak_dB

(

)

Compute the peak level in dB (full scale, normalized to 1). The equation is:

\( L_{pk} = 20\log_{10}{\max \mathrm{abs}(s[i])} \)

Returns

\( L_{pk} \mathrm{\ in\ dB} \)

Definition at line 55 of file conndetect_features.cpp.

peak_freq()

float Features::peak_freq

(

)

Compute the frequency at which the spectrum has the most power. It is defined as:

\( f_{pk} = \mathrm{arg\ max} \mathrm{abs}(\hat{S}[i]) \)

where

\( \hat{S}[i] \) denotes the short-time Fourier transform of \( s[i] \).

Returns

\( f_{pk} \)

Definition at line 129 of file conndetect_features.cpp.

rms_dB()

float Features::rms_dB

(

)

Compute the rms level in dB (full scale, normalized to 1). The equation is:

\( L_{rms} = 20\log_{10}\left(\sqrt{\frac{1}{N} \sum^{N-1}_{i=0} s[i]^2)}\right) \)

Returns

\( L_{rms} \mathrm{\ in\ dB} \)

Definition at line 65 of file conndetect_features.cpp.

setChannel()

void Features::setChannel

(

const Channel &

channel

)

Set channel data to operate on. BORROWS the data on which it operates, be carefull not to delete the underlying Channel!

Parameters

channel

the channel to operate on.

Definition at line 43 of file conndetect_features.cpp.

TM3()

float Features::TM3

(

)

Temporal moment 3, defined as.

\( TM3 = \left| 1/N \sum_{i=0}^{N-1} s[i]^3 \right| \)

Returns

\( TM3 \)

Definition at line 164 of file conndetect_features.cpp.

TM5()

float Features::TM5

(

)

Temporal moment 5, defined as.

\( TM5 = \left| 1/N \sum_{i=0}^{N-1} s[i]^5 \right| \)

Returns

\( TM5 \)

Definition at line 172 of file conndetect_features.cpp.

wamp()

float Features::wamp

(

float

wampl

)

Willson amplitude. Counts the number of difss in amplitude that have an absolute change in value larger than wampl;.

Parameters

wampl

the threshold difference

Returns

The number obtained.

Definition at line 143 of file conndetect_features.cpp.

zc()

float Features::zc

(

float

zc_l

)

Compute zero-crossings with a difference larger than zcl.

Parameters

zcl	the threshold change that is counted

Returns

The number of zero-crossings

Definition at line 153 of file conndetect_features.cpp.

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

• src/conndetect_features.h
• src/conndetect_features.cpp