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

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

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

Include dependency graph for wav2mfcc-pipe.c:

Go to the source code of this file.

Data Structures
struct	CMEAN
Defines
#define	CPMAX   500
	Maximum number of frames to store ceptral mean for CMN update.
#define	CPSTEP   5
	clist allocate step
Functions
void	WMP_init (Value para, float **bf, float *ssbuf, int ssbuflen)
DeltaBuf *	WMP_deltabuf_new (int veclen, int windowlen)
void	WMP_deltabuf_free (DeltaBuf *db)
void	WMP_deltabuf_prepare (DeltaBuf *db)
static void	WMP_deltabuf_calc (DeltaBuf *db, int cur)
boolean	WMP_deltabuf_proceed (DeltaBuf *db, float *new_mfcc)
boolean	WMP_deltabuf_flush (DeltaBuf *db)
void	CMN_realtime_init (int dimension, float weight)
void	CMN_realtime_prepare ()
void	CMN_realtime (float *mfcc, int dim)
void	CMN_realtime_update ()
static boolean	myread (void *buf, size_t unitbyte, int unitnum, FILE *fp)
static boolean	mywrite (void *buf, size_t unitbyte, int unitnum, int fd)
boolean	CMN_load_from_file (char *filename, int dim)
boolean	CMN_save_to_file (char *filename)
void	energy_max_init ()
void	energy_max_prepare (Value *para)
LOGPROB	energy_max_normalize (LOGPROB f, Value *para)
Variables
static CMEAN *	clist
	List of MFCC sum for previous inputs.
static int	clist_max
	Allocated number of CMEAN in clist.
static int	clist_num
	Currentlly filled CMEAN in clist.
static int	dim
	Local workarea to store the number of MFCC dimension.
static float	cweight
	Weight of initial cepstral mean.
static float *	cmean_init
	Initial cepstral mean for each input.
static boolean	cmean_init_set
	TRUE if cmean_init was set.
static CMEAN	now
	Work area to hold current cepstral mean.
static LOGPROB	energy_max_last
	Maximum energy value of last input.
static LOGPROB	energy_min_last
	Minimum floored energy value of last input.
static LOGPROB	energy_max
	Maximum energy value of current input.

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Detailed Description

Convert speech inputs into MFCC parameter vectors (per input frame).

Author:

Akinobu LEE

Date:

Thu Feb 17 18:12:30 2005

There are functions are derived from wav2mfcc.c, to compute MFCC vectors in per-frame basis. When performing on-line recognition, these functions will be used instead of ones in wav2mfcc.c

Revision

1.9

Definition in file wav2mfcc-pipe.c.

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Function Documentation

void WMP_init	(	Value	para,
		float **	bf,
		float *	ssbuf,
		int	ssbuflen
	)

initialize and setup buffers for a MFCC computataion.

Parameters:

	para	[in] configuration parameters
	bf	[out] pointer to the entry point of workspace for FFT
	ssbuf	[in] noise spectrum, or NULL if not using spectral subtraction
	ssbuflen	[in] length of above, ignoredwhen ssbuf is NULL

Definition at line 57 of file wav2mfcc-pipe.c.

Referenced by RealTimeInit(), and Wav2MFCC().

DeltaBuf* WMP_deltabuf_new	(	int	veclen,
		int	windowlen
	)

Allocate a new delta cycle buffer.

Parameters:

	veclen	[in] length of a vector
	windowlen	[in] window width for computing delta

Returns:

pointer to newly allocated delta cycle buffer structure.

Definition at line 83 of file wav2mfcc-pipe.c.

Referenced by RealTimeInit().

void WMP_deltabuf_free

(

DeltaBuf *

db

)

Destroy the delta cycle buffer.

Parameters:

db

[i/o] delta cycle buffer

Definition at line 110 of file wav2mfcc-pipe.c.

void WMP_deltabuf_prepare

(

DeltaBuf *

db

)

Reset and clear the delta cycle buffer.

Parameters:

db

[i/o] delta cycle buffer

Definition at line 128 of file wav2mfcc-pipe.c.

Referenced by RealTimePipeLinePrepare().

static void WMP_deltabuf_calc	(	DeltaBuf *	db,
		int	cur
	)			[static]

Calculate delta coefficients of the specified point in the cycle buffer.

Parameters:

	db	[i/o] delta cycle buffer
	cur	[in] target point to calculate the delta coefficients

Definition at line 144 of file wav2mfcc-pipe.c.

Referenced by WMP_deltabuf_flush(), and WMP_deltabuf_proceed().

boolean WMP_deltabuf_proceed	(	DeltaBuf *	db,
		float *	new_mfcc
	)

Store the given MFCC vector into the delta cycle buffer, and compute the latest delta coefficients.

Parameters:

	db	[i/o] delta cycle buffer
	new_mfcc	[in] MFCC vector

Returns:

TRUE if next delta coeff. computed, in that case it is saved in db->delta[], or FALSE if delta is not yet computed by short of data.

Definition at line 187 of file wav2mfcc-pipe.c.

Referenced by RealTimeParam(), and RealTimePipeLine().

boolean WMP_deltabuf_flush

(

DeltaBuf *

db

)

Flush the delta cycle buffer the delta coefficients left in the cycle buffer.

Parameters:

db

[i/o] delta cycle buffer

Returns:

TRUE if next delta coeff. computed, in that case it is saved in db->delta[], or FALSE if all delta computation has been flushed and no data is available.

Definition at line 229 of file wav2mfcc-pipe.c.

Referenced by RealTimeParam().

void CMN_realtime_init	(	int	dimension,
		float	weight
	)

Initialize MAP-CMN at startup.

Parameters:

	dimension	[in] vector dimension
	weight	[in] initial cepstral mean weight

Definition at line 290 of file wav2mfcc-pipe.c.

Referenced by RealTimeInit().

void CMN_realtime_prepare

(

)

Prepare for MAP-CMN at start of each input

Definition at line 317 of file wav2mfcc-pipe.c.

Referenced by RealTimePipeLinePrepare().

void CMN_realtime	(	float *	mfcc,
		int	dim
	)

Perform MAP-CMN for incoming MFCC vectors

Parameters:

	mfcc	[in] MFCC vector
	dim	[in] dimension

Definition at line 332 of file wav2mfcc-pipe.c.

Referenced by RealTimeParam(), and RealTimePipeLine().

void CMN_realtime_update

(

)

Update initial cepstral mean from previous utterances for next input.

Definition at line 360 of file wav2mfcc-pipe.c.

Referenced by RealTimeCMNUpdate().

static boolean myread	(	void *	buf,
		size_t	unitbyte,
		int	unitnum,
		FILE *	fp
	)			[static]

Read binary with byte swap (assume file is Big Endian)

Parameters:

	buf	[out] data buffer
	unitbyte	[in] size of unit in bytes
	unitnum	[in] number of units to be read
	fp	[in] file pointer

Returns:

TRUE if required number of units are fully read, FALSE if failed.

Definition at line 414 of file wav2mfcc-pipe.c.

static boolean mywrite	(	void *	buf,
		size_t	unitbyte,
		int	unitnum,
		int	fd
	)			[static]

Write binary with byte swap (assume data is Big Endian)

Parameters:

	buf	[in] data buffer
	unitbyte	[in] size of unit in bytes
	unitnum	[in] number of units to write
	fd	[in] file descriptor

Returns:

TRUE if required number of units are fully written, FALSE if failed.

Definition at line 436 of file wav2mfcc-pipe.c.

boolean CMN_load_from_file	(	char *	filename,
		int	dim
	)

Load CMN parameter from file. If the number of MFCC dimension in the file does not match the specified one, an error will occur.

Parameters:

	filename	[in] file name
	dim	[in] required number of MFCC dimensions

Returns:

TRUE on success, FALSE on failure.

Definition at line 460 of file wav2mfcc-pipe.c.

Referenced by RealTimeInit().

boolean CMN_save_to_file

(

char *

filename

)

Save the current CMN vector to a file.

Parameters:

filename

[in] filename to save the data.

Returns:

TRUE on success, FALSE on failure.

Definition at line 504 of file wav2mfcc-pipe.c.

Referenced by RealTimeCMNUpdate().

void energy_max_init

(

)

Initialize work area for energy normalization on live input. This should be called once on startup.

Definition at line 543 of file wav2mfcc-pipe.c.

Referenced by RealTimeInit().

void energy_max_prepare

(

Value *

para

)

Prepare values for energy normalization on live input. This should be called before each input segment.

Parameters:

para

[in] MFCC computation configuration parameter

Definition at line 555 of file wav2mfcc-pipe.c.

Referenced by RealTimePipeLinePrepare().

LOGPROB energy_max_normalize	(	LOGPROB	f,
		Value *	para
	)

Peform energy normalization using maximum of last input.

Parameters:

	f	[in] raw energy
	para	[in] MFCC computation configuration parameter

Returns:

value of the normalized log energy.

Definition at line 571 of file wav2mfcc-pipe.c.

Referenced by RealTimePipeLine().

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