libsent/src/wav2mfcc/wav2mfcc-buffer.c File Reference

Convert speech inputs into MFCC parameter vectors (per utterance). More...

#include <sent/stddefs.h>
#include <sent/mfcc.h>

Include dependency graph for wav2mfcc-buffer.c:

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Functions
int	Wav2MFCC (SP16 *wave, float **mfcc, Value para, int nSamples, float *ssbuf, int ssbuflen)
void	NormaliseLogE (float **mfcc, int frame_num, Value para)
void	Delta (float **c, int frame, Value para)
void	Accel (float **c, int frame, Value para)
void	CMN (float **mfcc, int frame_num, int dim)

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Detailed Description

Convert speech inputs into MFCC parameter vectors (per utterance).

Author:

Akinobu LEE

Date:

Thu Feb 17 17:43:35 2005

This file contains functions to convert the whole speech input to MFCC vector array. The frame-wise MFCC computation needed for real-time recognition is defined in wav2mfcc-pipe.c.

The supported format is MFCC[_0][_E][_D][_A][_Z].

Revision

1.6

Definition in file wav2mfcc-buffer.c.

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Function Documentation

int Wav2MFCC	(	SP16 *	wave,
		float **	mfcc,
		Value	para,
		int	nSamples,
		float *	ssbuf,
		int	ssbuflen
	)

Convert wave data to MFCC. Also does spectral subtraction if ssbuf specified.

Parameters:

	wave	[in] waveform data
	mfcc	[out] buffer to store the resulting MFCC parameter vector [t][0..veclen-1], should be already allocated
	para	[in] configuration parameters
	nSamples	[in] length of waveform data
	ssbuf	[in] buffer that holds noise spectrum to be subtracted from input, or NULL if not use spectral subtraction
	ssbuflen	[in] length of above, ignored when ssbuf is NULL

Returns:

the number of processed frames.

Definition at line 56 of file wav2mfcc-buffer.c.

Referenced by new_wav2mfcc().

void NormaliseLogE	(	float **	mfcc,
		int	frame_num,
		Value	para
	)

Normalise log energy

Parameters:

	mfcc	[i/o] array of MFCC vectors
	frame_num	[in] number of frames
	para	[in] configuration parameters

Definition at line 108 of file wav2mfcc-buffer.c.

void Delta	(	float **	c,
		int	frame,
		Value	para
	)

Calculate delta coefficients

Parameters:

	c	[i/o] MFCC vectors, in which the delta coeff. will be appended.
	frame	[in] number of frames
	para	[in] configuration parameters

Definition at line 140 of file wav2mfcc-buffer.c.

void Accel	(	float **	c,
		int	frame,
		Value	para
	)

Calculate acceleration coefficients.

Parameters:

	c	[i/o] MFCC vectors, in which the delta coeff. will be appended.
	frame	[in] number of frames
	para	[in] configuration parameters

Definition at line 188 of file wav2mfcc-buffer.c.

void CMN	(	float **	mfcc,
		int	frame_num,
		int	dim
	)

Cepstrum Mean Normalization (buffered) Cepstral mean will be computed within the given MFCC vectors.

Parameters:

	mfcc	[i/o] array of MFCC vectors
	frame_num	[in] number of frames
	dim	[in] total dimension of MFCC vectors

Definition at line 227 of file wav2mfcc-buffer.c.

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