SMelBanksI Class Reference

Calculation of Mel-bank energies. More...

#include <bsapi.h>

Inheritance diagram for SMelBanksI:

List of all members.

Public Member Functions
virtual void BSAPI_METHOD	SetSampleFreq (int sampleFreq=8000)=0
	Set sampling frequency.
virtual void BSAPI_METHOD	SetVectorSize (int vectorSize=200)=0
	Set vector size.
virtual void BSAPI_METHOD	SetStep (int step=80)=0
	Set frame step.
virtual void BSAPI_METHOD	SetPreemCoef (float preemCoef=0.0f)=0
	Set pre-emphasis coefficient.
virtual void BSAPI_METHOD	SetNBanks (int nBanks=15)=0
	Set number of Mel-banks.
virtual void BSAPI_METHOD	SetLowFreq (float loFreq=0.0f)=0
	Set low cut-off frequency.
virtual void BSAPI_METHOD	SetHighFreq (float hiFreq=4000.0f)=0
	Set high cut-off frequency.
virtual void BSAPI_METHOD	SetLowWarpFreq (float loFreq=3000.0f)=0
	Set low warp frequency for VTLN.
virtual void BSAPI_METHOD	SetHighWarpFreq (float hiFreq=3000.0f)=0
	Set high warp frequency for VTLN.
virtual bool BSAPI_METHOD	SetWarpAlpha (float alpha=1.0f)=0
	Set warping factor for WTLN.
virtual void BSAPI_METHOD	SetWaitForWarpingFactor (bool waitForWarpingFactor=false)=0
	Wait for warping factor.
virtual void BSAPI_METHOD	SetZMeanSource (bool zMeanSource=false)=0
	Remove mean value from each frame.
virtual void BSAPI_METHOD	SetTakeLog (bool takeLog=true)=0
	Take logarithm of energies at the output from Mel-banks.
virtual void BSAPI_METHOD	SetUsePower (bool usePower=true)=0
	Use power spectra instead of magnitude spectra.
virtual void BSAPI_METHOD	SetAddEnergy (bool addEnergy=false)=0
	Add logarithm of frame energy as an additional coefficient.
virtual void BSAPI_METHOD	SetUseRawEnergy (bool useRawEnergy=false)=0
	Calculate energy after mean removal instead of after Hamming windowing.
virtual void BSAPI_METHOD	SetNormalizeEnergy (bool normalizeEnergy=false)=0
	Enable normalization of temporal evolution of the log energy coefficient.
virtual void BSAPI_METHOD	SetEnergyScale (float energyScale=0.1f)=0
	Set scale factor for energy normalization.
virtual void BSAPI_METHOD	SetEnergyFloor (float energyFloor=50.0f)=0
	Set energy floor for energy normalization.
virtual void BSAPI_METHOD	SetDebug (bool debug=false)=0
	Dump Mel-banks configuration parameters and numerical values of data after each processing step.
virtual void BSAPI_METHOD	SetStartFrameRepetition (int startFrameRepetition=0)=0
	Repeate the first frame.
virtual void BSAPI_METHOD	SetEndFrameRepetition (int endFrameRepetition=0)=0
	Repeate the last frame.
virtual void BSAPI_METHOD	SetSpectralShiftHz (float spectralShiftHz=0.0f)=0
	Set the spectral shift.
virtual int BSAPI_METHOD	GetSampleFreq ()=0
virtual int BSAPI_METHOD	GetVectorSize ()=0
virtual int BSAPI_METHOD	GetStep ()=0
virtual float BSAPI_METHOD	GetPreemCoef ()=0
virtual int BSAPI_METHOD	GetNBanks ()=0
virtual float BSAPI_METHOD	GetLowFreq ()=0
virtual float BSAPI_METHOD	GetHighFreq ()=0
virtual float BSAPI_METHOD	GetWarpAlpha ()=0
virtual float BSAPI_METHOD	GetLowWarpFreq ()=0
virtual float BSAPI_METHOD	GetHighWarpFreq ()=0
virtual bool BSAPI_METHOD	GetZMeanSource ()=0
virtual bool BSAPI_METHOD	GetTakeLog ()=0
virtual float *BSAPI_METHOD	GetCenters ()=0
virtual int BSAPI_METHOD	GetStartFrameRepetition ()=0
virtual int BSAPI_METHOD	GetEndFrameRepetition ()=0
virtual void BSAPI_METHOD	SetOutBatchSize (int outBatchSize=0)=0
	Number of frames sent to output in one batch.
virtual void BSAPI_METHOD	Reset ()=0

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Detailed Description

Calculation of Mel-bank energies.

The per frame signal processing steps are: remove mean from waveform, pre-emphasis, Hamming window, FFT power, power to amplitude, Mel-bank application, logarithm.

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Member Function Documentation

virtual void BSAPI_METHOD SMelBanksI::SetAddEnergy

(

bool

addEnergy = false

)

[pure virtual]

Add logarithm of frame energy as an additional coefficient.

Parameters:

addEnergy

true to add the energy coefficient

virtual void BSAPI_METHOD SMelBanksI::SetDebug

(

bool

debug = false

)

[pure virtual]

Dump Mel-banks configuration parameters and numerical values of data after each processing step.

Parameters:

debug

true to enable debug mode

virtual void BSAPI_METHOD SMelBanksI::SetEndFrameRepetition

(

int

endFrameRepetition = 0

)

[pure virtual]

Repeate the last frame.

This helps to fill up buffers of some subsequent algorithms for synchronization.

Parameters:

endFrameRepetition

number of times the last frame should be repeated

virtual void BSAPI_METHOD SMelBanksI::SetEnergyFloor

(

float

energyFloor = 50.0f

)

[pure virtual]

Set energy floor for energy normalization.

Parameters:

energyFloor

energy floor in dBs

virtual void BSAPI_METHOD SMelBanksI::SetEnergyScale

(

float

energyScale = 0.1f

)

[pure virtual]

Set scale factor for energy normalization.

Parameters:

energyScale

scale factor

virtual void BSAPI_METHOD SMelBanksI::SetHighFreq

(

float

hiFreq = 4000.0f

)

[pure virtual]

Set high cut-off frequency.

Parameters:

hiFreq

high cut-off frequency in Hertzs

virtual void BSAPI_METHOD SMelBanksI::SetHighWarpFreq

(

float

hiFreq = 3000.0f

)

[pure virtual]

Set high warp frequency for VTLN.

Parameters:

hiFreq

high warp frequency in Hertzs

virtual void BSAPI_METHOD SMelBanksI::SetLowFreq

(

float

loFreq = 0.0f

)

[pure virtual]

Set low cut-off frequency.

Parameters:

loFreq

low cut-off frequency in Hertzs

virtual void BSAPI_METHOD SMelBanksI::SetLowWarpFreq

(

float

loFreq = 3000.0f

)

[pure virtual]

Set low warp frequency for VTLN.

Parameters:

loFreq

low warp frequency in Hertzs

virtual void BSAPI_METHOD SMelBanksI::SetNBanks

(

int

nBanks = 15

)

[pure virtual]

Set number of Mel-banks.

Parameters:

nBanks

number of Mel-banks

virtual void BSAPI_METHOD SMelBanksI::SetNormalizeEnergy

(

bool

normalizeEnergy = false

)

[pure virtual]

Enable normalization of temporal evolution of the log energy coefficient.

This enables normalization of temporal evolution of the log energy coefficient. At first, the minimal value is limited using EnergyFloor. Then the the energy is converted using formula "new_energy = 1 - (max - log(energy)) * EnergyScale". The max value is the maximal energy found over all frames. The normalization can be applied in the offline mode only.

Parameters:

normalizeEnergy

true to enable normalization

virtual void BSAPI_METHOD SMelBanksI::SetOutBatchSize

(

int

outBatchSize = 0

)

[pure virtual]

Number of frames sent to output in one batch.

This function is important for the online mode (controlled by the OnWaveform flags). In the offline mode, all the data are packed to one matrix.

Parameters:

outBatchSize

number of frames or 0 to enforce offline mode and pack everything to one matrix

virtual void BSAPI_METHOD SMelBanksI::SetPreemCoef

(

float

preemCoef = 0.0f

)

[pure virtual]

Set pre-emphasis coefficient.

Parameters:

preemCoef

pre-emphasis coefficient, 0 means that pre-emphasis is not applied

virtual void BSAPI_METHOD SMelBanksI::SetSampleFreq

(

int

sampleFreq = 8000

)

[pure virtual]

Set sampling frequency.

Parameters:

sampleFreq

sampling frequency

virtual void BSAPI_METHOD SMelBanksI::SetSpectralShiftHz

(

float

spectralShiftHz = 0.0f

)

[pure virtual]

Set the spectral shift.

Shift the spectrum and compensate for mistuning of the carrier frequency in HF transmission

Parameters:

spectralShiftHz

spectral shift in Hertzs (- to left, + to right)

virtual void BSAPI_METHOD SMelBanksI::SetStartFrameRepetition

(

int

startFrameRepetition = 0

)

[pure virtual]

Repeate the first frame.

This helps to fill up buffers of some subsequent algorithms for synchronization.

Parameters:

startFrameRepetition

number of times the first frame should be repeated

virtual void BSAPI_METHOD SMelBanksI::SetStep

(

int

step = 80

)

[pure virtual]

Set frame step.

Parameters:

step	frame step in samples

virtual void BSAPI_METHOD SMelBanksI::SetTakeLog

(

bool

takeLog = true

)

[pure virtual]

Take logarithm of energies at the output from Mel-banks.

Parameters:

takeLog

true to enable logarithm at the output from Mel-banks

virtual void BSAPI_METHOD SMelBanksI::SetUsePower

(

bool

usePower = true

)

[pure virtual]

Use power spectra instead of magnitude spectra.

Parameters:

usePower

true to use power spectra instead of magnitude spectra

virtual void BSAPI_METHOD SMelBanksI::SetUseRawEnergy

(

bool

useRawEnergy = false

)

[pure virtual]

Calculate energy after mean removal instead of after Hamming windowing.

This is for the additional energy parameter. See the SMelBanksI description for signal processing steps.

Parameters:

useRawEnergy

true to use raw energy

virtual void BSAPI_METHOD SMelBanksI::SetVectorSize

(

int

vectorSize = 200

)

[pure virtual]

Set vector size.

Parameters:

vectorSize

vector size or frame size in samples

virtual void BSAPI_METHOD SMelBanksI::SetWaitForWarpingFactor

(

bool

waitForWarpingFactor = false

)

[pure virtual]

Wait for warping factor.

This is a synchronization mechanism. If the waiting for warping factor is enabled, the object only stores a pointer to waveform when it comes and the waveform is is processed after the warping facor have been received. This synchronization works in the offline processing mode only.

Parameters:

waitForWarpingFactor

true if waiting for warping factor is enabled.

virtual bool BSAPI_METHOD SMelBanksI::SetWarpAlpha

(

float

alpha = 1.0f

)

[pure virtual]

Set warping factor for WTLN.

Parameters:

alpha

VTLN warping factor

Returns:

true if the new Mel-bank was dessigned correctly

virtual void BSAPI_METHOD SMelBanksI::SetZMeanSource

(

bool

zMeanSource = false

)

[pure virtual]

Remove mean value from each frame.

Parameters:

zMeanSource

true to enable the mean removal

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

• bsapi.h