Implementation of HMM base structure. More...
#include <stdio.h>
#include <fixpoint.h>
#include <listelem_alloc.h>
Go to the source code of this file.
Data Structures | |
struct | hmm_context_s |
struct | hmm_state_t |
A single state in the HMM. More... | |
struct | hmm_s |
Defines | |
#define | SENSCR_SHIFT 10 |
Shift count for senone scores. | |
#define | WORST_SCORE ((int)0xE0000000) |
Large negative number. | |
#define | HMM_MAX_NSTATE 5 |
Hard-coded limit on the number of emitting states. | |
#define | hmm_context(h) (h)->ctx |
Access macros. | |
#define | hmm_is_mpx(h) (h)->mpx |
#define | hmm_state(h, st) (h)->state[st] |
#define | hmm_in_score(h) hmm_state(h,0).score |
#define | hmm_score(h, st) hmm_state(h,st).score |
#define | hmm_out_score(h) (h)->out.score |
#define | hmm_in_history(h) hmm_state(h,0).history |
#define | hmm_history(h, st) hmm_state(h,st).history |
#define | hmm_out_history(h) (h)->out.history |
#define | hmm_bestscore(h) (h)->bestscore |
#define | hmm_frame(h) (h)->frame |
#define | hmm_mpx_ssid(h, st) (h)->s.mpx_ssid[st] |
#define | hmm_nonmpx_ssid(h) (h)->s.ssid |
#define | hmm_ssid(h, st) |
#define | hmm_senid(h, st) |
#define | hmm_senscr(h, st) |
#define | hmm_tmatid(h) (h)->tmatid |
#define | hmm_tprob(h, i, j) (h)->ctx->tp[hmm_tmatid(h)][i][j] |
#define | hmm_n_emit_state(h) ((h)->n_emit_state) |
#define | hmm_n_state(h) ((h)->n_emit_state + 1) |
#define | hmm_context_set_senscore(ctx, senscr) ((ctx)->senscore = (senscr)) |
Change the senone score array for a context. | |
Typedefs | |
typedef float32 | mean_t |
typedef float32 | var_t |
typedef struct hmm_context_s | hmm_context_t |
typedef struct hmm_s | hmm_t |
Functions | |
hmm_context_t * | hmm_context_init (int32 n_emit_state, int32 **const *tp, int16 const *senscore, int16 *const *sseq) |
Create an HMM context. | |
void | hmm_context_free (hmm_context_t *ctx) |
Free an HMM context. | |
void | hmm_init (hmm_context_t *ctx, hmm_t *hmm, int mpx, int ssid, int tmatid) |
Populate a previously-allocated HMM structure, allocating internal data. | |
void | hmm_deinit (hmm_t *hmm) |
Free an HMM structure, releasing internal data (but not the HMM structure itself). | |
void | hmm_clear (hmm_t *h) |
Reset the states of the HMM to the invalid condition. | |
void | hmm_clear_scores (hmm_t *h) |
Reset the scores of the HMM. | |
void | hmm_normalize (hmm_t *h, int32 bestscr) |
Renormalize the scores in this HMM based on the given best score. | |
void | hmm_enter (hmm_t *h, int32 score, int32 histid, int frame) |
Enter an HMM with the given path score and history ID. | |
int32 | hmm_vit_eval (hmm_t *hmm) |
Viterbi evaluation of given HMM. | |
int32 | hmm_dump_vit_eval (hmm_t *hmm, FILE *fp) |
Like hmm_vit_eval, but dump HMM state and relevant senscr to fp first, for debugging;. | |
void | hmm_dump (hmm_t *h, FILE *fp) |
For debugging, dump the whole HMM out. |
Implementation of HMM base structure.
HMM data structure and operation.
Hidden Markov Model base structures.
For efficiency, this version is hardwired for two possible HMM topologies, but will fall back to others:
5-state left-to-right HMMs: (0 is the *emitting* entry state and E is a non-emitting exit state; the x's indicate allowed transitions between source and destination states):
0 1 2 3 4 E (destination-states) 0 x x x 1 x x x 2 x x x 3 x x x 4 x x (source-states)
5-state topologies that contain a subset of the above transitions should work as well.
3-state left-to-right HMMs (similar notation as the 5-state topology above):
0 1 2 E (destination-states) 0 x x x 1 x x x 2 x x (source-states)
3-state topologies that contain a subset of the above transitions should work as well.
Definition in file hmm.h.
#define hmm_senid | ( | h, | ||
st | ||||
) |
#define hmm_senscr | ( | h, | ||
st | ||||
) |
(hmm_ssid(h,st) == -1 \ ? WORST_SCORE \ : -(h)->ctx->senscore[hmm_senid(h,st)] << SENSCR_SHIFT)
#define hmm_ssid | ( | h, | ||
st | ||||
) |
#define SENSCR_SHIFT 10 |
#define WORST_SCORE ((int)0xE0000000) |
Large negative number.
This number must be small enough so that 4 times WORST_SCORE will not overflow. The reason for this is that the search doesn't check the scores in a model before evaluating the model and it may require as many was 4 plies before the new 'good' score can wipe out the initial WORST_SCORE initialization.
Definition at line 72 of file hmm.h.
Referenced by ngram_compute_seg_scores(), ngram_fwdflat_search(), ngram_fwdtree_search(), and ngram_search_lattice().
void hmm_clear | ( | hmm_t * | h | ) |
void hmm_context_free | ( | hmm_context_t * | ctx | ) |
void hmm_dump | ( | hmm_t * | h, | |
FILE * | fp | |||
) |
int32 hmm_dump_vit_eval | ( | hmm_t * | hmm, | |
FILE * | fp | |||
) |
int32 hmm_vit_eval | ( | hmm_t * | hmm | ) |
Viterbi evaluation of given HMM.