Acoustic model structures for PocketSphinx. More...

#include <assert.h>
#include <prim_type.h>
#include <err.h>
#include <cmd_ln.h>
#include <strfuncs.h>
#include <string.h>
#include <byteorder.h>
#include <feat.h>
#include "cmdln_macro.h"
#include "acmod.h"
#include "s2_semi_mgau.h"
#include "ptm_mgau.h"
#include "ms_mgau.h"

Defines
#define	WORDS_BIGENDIAN 1
#define	MPX_BITVEC_SET(a, h, i)
#define	NONMPX_BITVEC_SET(a, h, i)
Functions
int	acmod_fe_mismatch (acmod_t acmod, fe_t fe)
int	acmod_feat_mismatch (acmod_t acmod, feat_t fcb)
acmod_t *	acmod_init (cmd_ln_t config, logmath_t lmath, fe_t fe, feat_t fcb)
	Initialize an acoustic model.
void	acmod_free (acmod_t *acmod)
	Finalize an acoustic model.
ps_mllr_t *	acmod_update_mllr (acmod_t acmod, ps_mllr_t mllr)
	Adapt acoustic model using a linear transform.
int	acmod_set_mfcfh (acmod_t acmod, FILE logfh)
	Start logging MFCCs to a filehandle.
int	acmod_set_rawfh (acmod_t acmod, FILE logfh)
	Start logging raw audio to a filehandle.
void	acmod_grow_feat_buf (acmod_t *acmod, int nfr)
int	acmod_set_grow (acmod_t *acmod, int grow_feat)
	Set memory allocation policy for utterance processing.
int	acmod_start_utt (acmod_t *acmod)
	Mark the start of an utterance.
int	acmod_end_utt (acmod_t *acmod)
	Mark the end of an utterance.
int	acmod_process_raw (acmod_t acmod, int16 const inout_raw, size_t inout_n_samps, int full_utt)
	TODO: Set queue length for utterance processing.
int	acmod_process_cep (acmod_t acmod, mfcc_t *inout_cep, int inout_n_frames, int full_utt)
	Feed acoustic feature data into the acoustic model for scoring.
int	acmod_process_feat (acmod_t acmod, mfcc_t *feat)
	Feed dynamic feature data into the acoustic model for scoring.
int	acmod_rewind (acmod_t *acmod)
	Rewind the current utterance, allowing it to be rescored.
int	acmod_advance (acmod_t *acmod)
	Advance the frame index.
int16 const *	acmod_score (acmod_t acmod, int inout_frame_idx)
	Score one frame of data.
int	acmod_best_score (acmod_t acmod, int out_best_senid)
	Get best score and senone index for current frame.
void	acmod_clear_active (acmod_t *acmod)
	Clear set of active senones.
void	acmod_activate_hmm (acmod_t acmod, hmm_t hmm)
	Activate senones associated with an HMM.

Detailed Description

Acoustic model structures for PocketSphinx.

Author:: David Huggins-Daines <dhuggins@cs.cmu.edu>

Definition in file acmod.c.

Define Documentation

#define MPX_BITVEC_SET	(	a,
		h,
		i
	)

Value:

if (hmm_mpx_ssid(h,i) != BAD_SSID)                          \
        bitvec_set((a)->senone_active_vec, hmm_mpx_senid(h,i))

Definition at line 879 of file acmod.c.

#define NONMPX_BITVEC_SET	(	a,
		h,
		i
	)

Value:

bitvec_set((a)->senone_active_vec,                                  \
               hmm_nonmpx_senid(h,i))

Definition at line 882 of file acmod.c.

Function Documentation

int acmod_advance ( acmod_t * acmod )

Advance the frame index.

This function moves to the next frame of input data. Subsequent calls to acmod_score() will return scores for that frame, until the next call to acmod_advance().

Returns:: New frame index.

Definition at line 781 of file acmod.c.

References acmod_s::feat_outidx, ps_mgau_s::frame_idx, acmod_s::mgau, acmod_s::n_feat_alloc, acmod_s::n_feat_frame, and acmod_s::output_frame.

acmod_t* acmod_init	(	cmd_ln_t *	config,
		logmath_t *	lmath,
		fe_t *	fe,
		feat_t *	fcb
	)

Initialize an acoustic model.

Parameters:

	config	a command-line object containing parameters. This pointer is not retained by this object.
	lmath	global log-math parameters.
	fe	a previously-initialized acoustic feature module to use, or NULL to create one automatically. If this is supplied and its parameters do not match those in the acoustic model, this function will fail. This pointer is not retained.
	fe	a previously-initialized dynamic feature module to use, or NULL to create one automatically. If this is supplied and its parameters do not match those in the acoustic model, this function will fail. This pointer is not retained.

Returns:: a newly initialized acmod_t, or NULL on failure.

Definition at line 225 of file acmod.c.

References acmod_free(), acmod_s::compallsen, acmod_s::config, acmod_s::fcb, acmod_s::fe, acmod_s::feat_buf, acmod_s::lmath, acmod_s::log_zero, acmod_s::mdef, acmod_s::mfc_buf, acmod_s::n_feat_alloc, acmod_s::n_mfc_alloc, acmod_s::senone_active, acmod_s::senone_active_vec, acmod_s::senone_scores, and acmod_s::state.

Referenced by ps_reinit().

int acmod_process_cep	(	acmod_t *	acmod,
		mfcc_t ***	inout_cep,
		int *	inout_n_frames,
		int	full_utt
	)

Feed acoustic feature data into the acoustic model for scoring.

Parameters:

	inout_cep	In: Pointer to buffer of features Out: Pointer to next frame to be read
	inout_n_frames	In: Number of frames available Out: Number of frames remaining
	full_utt	If non-zero, this block represents a full utterance and should be processed as such.

Returns:: Number of frames of data processed.

Definition at line 647 of file acmod.c.

References ACMOD_ENDED, ACMOD_STARTED, acmod_s::fcb, acmod_s::feat_buf, acmod_s::feat_outidx, acmod_s::grow_feat, acmod_s::mfcfh, acmod_s::n_feat_alloc, acmod_s::n_feat_frame, and acmod_s::state.

int acmod_process_feat	(	acmod_t *	acmod,
		mfcc_t **	feat
	)

Feed dynamic feature data into the acoustic model for scoring.

Unlike acmod_process_raw() and acmod_process_cep(), this function accepts a single frame at a time. This is because there is no need to do buffering when using dynamic features as input. However, if the dynamic feature buffer is full, this function will fail, so you should either always check the return value, or always pair a call to it with a call to acmod_score().

Parameters:

feat

Pointer to one frame of dynamic features.

Returns:: Number of frames processed (either 0 or 1).

Definition at line 739 of file acmod.c.

References acmod_s::fcb, acmod_s::feat_buf, acmod_s::feat_outidx, acmod_s::grow_feat, acmod_s::n_feat_alloc, and acmod_s::n_feat_frame.

int acmod_process_raw	(	acmod_t *	acmod,
		int16 const **	inout_raw,
		size_t *	inout_n_samps,
		int	full_utt
	)

TODO: Set queue length for utterance processing.

This function allows multiple concurrent passes of search to operate on different parts of the utterance. Feed raw audio data to the acoustic model for scoring.

Parameters:

	inout_raw	In: Pointer to buffer of raw samples Out: Pointer to next sample to be read
	inout_n_samps	In: Number of samples available Out: Number of samples remaining
	full_utt	If non-zero, this block represents a full utterance and should be processed as such.

Returns:: Number of frames of data processed.

Definition at line 578 of file acmod.c.

References acmod_s::fe, acmod_s::mfc_buf, acmod_s::mfc_outidx, acmod_s::n_mfc_alloc, acmod_s::n_mfc_frame, and acmod_s::rawfh.

Referenced by ps_process_raw().

int acmod_rewind ( acmod_t * acmod )

Rewind the current utterance, allowing it to be rescored.

After calling this function, the internal frame index is reset, and acmod_score() will return scores starting at the first frame of the current utterance. Currently, acmod_set_grow() must have been called to enable growing the feature buffer in order for this to work. In the future, senone scores may be cached instead.

Returns:: 0 for success, <0 for failure (if the utterance can't be rewound due to no feature or score data available)

Definition at line 762 of file acmod.c.

References acmod_s::feat_outidx, ps_mgau_s::frame_idx, acmod_s::mgau, acmod_s::n_feat_alloc, acmod_s::n_feat_frame, acmod_s::output_frame, and acmod_s::senscr_frame.

int16 const* acmod_score	(	acmod_t *	acmod,
		int *	inout_frame_idx
	)

Score one frame of data.

Parameters:

inout_frame_idx

Input: frame index to score, or -1 or NULL to obtain scores for the most recent frame. Output: frame index corresponding to this set of scores.

Returns:: Array of senone scores for this frame, or NULL if no frame is available for scoring (such as if a frame index is requested that is not yet or no longer available). The data pointed to persists only until the next call to acmod_score() or acmod_advance().

Definition at line 793 of file acmod.c.

References acmod_s::compallsen, acmod_s::feat_buf, acmod_s::feat_outidx, acmod_s::mgau, acmod_s::n_feat_alloc, acmod_s::n_feat_frame, acmod_s::n_senone_active, acmod_s::output_frame, acmod_s::senone_active, acmod_s::senone_scores, and acmod_s::senscr_frame.

Referenced by ngram_fwdflat_search(), and ngram_fwdtree_search().

int acmod_set_grow	(	acmod_t *	acmod,
		int	grow_feat
	)

Set memory allocation policy for utterance processing.

Parameters:

grow_feat

If non-zero, the internal dynamic feature buffer will expand as necessary to encompass any amount of data fed to the model.

Returns:: previous allocation policy.

Definition at line 384 of file acmod.c.

References acmod_s::grow_feat, and acmod_s::n_feat_alloc.

Referenced by ps_process_raw(), and ps_reinit().

int acmod_set_mfcfh	(	acmod_t *	acmod,
		FILE *	logfh
	)

Start logging MFCCs to a filehandle.

Parameters:

	acmod	Acoustic model object.
	logfh	Filehandle to log to.

Returns:: 0 for success, <0 on error.

Definition at line 346 of file acmod.c.

References acmod_s::mfcfh.

Referenced by ps_start_utt().

int acmod_set_rawfh	(	acmod_t *	acmod,
		FILE *	logfh
	)

Start logging raw audio to a filehandle.

Parameters:

	acmod	Acoustic model object.
	logfh	Filehandle to log to.

Returns:: 0 for success, <0 on error.

Definition at line 358 of file acmod.c.

References acmod_s::rawfh.

Referenced by ps_start_utt().

ps_mllr_t* acmod_update_mllr	(	acmod_t *	acmod,
		ps_mllr_t *	mllr
	)

Adapt acoustic model using a linear transform.

Parameters:

mllr

The new transform to use, or NULL to update the existing transform. The decoder retains ownership of this pointer, so you should not attempt to free it manually. Use ps_mllr_retain() if you wish to reuse it elsewhere.

Returns:: The updated transform object for this decoder, or NULL on failure.

Definition at line 335 of file acmod.c.

References acmod_s::mgau, acmod_s::mllr, and ps_mllr_free().

Referenced by ps_update_mllr().

src/libpocketsphinx/acmod.c File Reference

Defines

Functions

Detailed Description

Define Documentation

Function Documentation