SphinxBase 5prealpha
ngram_model_internal.h
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37/*
38 * \file ngram_model_internal.h Internal structures for N-Gram models
39 *
40 * Author: David Huggins-Daines <dhuggins@cs.cmu.edu>
41 */
42
43#ifndef __NGRAM_MODEL_INTERNAL_H__
44#define __NGRAM_MODEL_INTERNAL_H__
45
48
57 uint32 *n_counts;
58 int32 n_1g_alloc;
59 int32 n_words;
62 uint8 n;
63 uint8 n_classes;
64 uint8 writable;
65 uint8 flags;
68 float32 lw;
69 int32 log_wip;
70 int32 log_zero;
71 char **word_str;
73 int32 *tmp_wids;
76};
77
82 int32 tag_wid;
83 int32 start_wid;
84 int32 n_words;
85 int32 *prob1;
89 struct ngram_hash_s {
90 int32 wid;
91 int32 prob1;
92 int32 next;
93 } *nword_hash;
94 int32 n_hash;
96};
97
98#define NGRAM_MAX_ORDER 5
99
100#define NGRAM_HASH_SIZE 128
101
102#define NGRAM_BASEWID(wid) ((wid)&0xffffff)
103#define NGRAM_CLASSID(wid) (((wid)>>24) & 0x7f)
104#define NGRAM_CLASSWID(wid,classid) (((classid)<<24) | 0x80000000 | (wid))
105#define NGRAM_IS_CLASSWID(wid) ((wid)&0x80000000)
106
107#define UG_ALLOC_STEP 10
108
110typedef struct ngram_funcs_s {
114 void (*free) (ngram_model_t * model);
118 int (*apply_weights) (ngram_model_t * model, float32 lw, float32 wip);
122 int32(*score) (ngram_model_t * model,
123 int32 wid,
124 int32 * history, int32 n_hist, int32 * n_used);
129 int32(*raw_score) (ngram_model_t * model,
130 int32 wid,
131 int32 * history, int32 n_hist, int32 * n_used);
143 int32(*add_ug) (ngram_model_t * model, int32 wid, int32 lweight);
144
148 void (*flush) (ngram_model_t * model);
150
154typedef struct classdef_s {
155 char **words;
156 float32 *weights;
157 int32 n_words;
158} classdef_t;
159
163int32
164ngram_model_init(ngram_model_t * model,
165 ngram_funcs_t * funcs,
166 logmath_t * lmath, int32 n, int32 n_unigram);
167
171int32 read_classdef_file(hash_table_t * classes,
172 const char *classdef_file);
173
177void classdef_free(classdef_t * classdef);
178
182ngram_class_t *ngram_class_new(ngram_model_t * model, int32 tag_wid,
183 int32 start_wid, glist_t classwords);
184
188void ngram_class_free(ngram_class_t * lmclass);
189
195int32 ngram_class_prob(ngram_class_t * lmclass, int32 wid);
196
197#endif /* __NGRAM_MODEL_INTERNAL_H__ */
Hash table implementation.
N-Gram language models.
One class definition from a classdef file.
A node in a generic list.
Definition glist.h:100
Custom hash table for additional words.
int32 prob1
Probability for this word.
int32 next
Index of next bucket (or -1 for no collision)
int32 wid
Word ID of this bucket.
Implementation of ngram_class_t.
int32 start_wid
Starting base word ID for this class' words.
int32 * prob1
Probability table for base words.
int32 n_hash_inuse
Number of words in nword_hash.
int32 n_hash
Number of buckets in nword_hash (power of 2)
int32 tag_wid
Base word ID for this class tag.
int32 n_words
Number of base words for this class.
Implementation-specific functions for operating on ngram_model_t objects.
int32(* raw_score)(ngram_model_t *model, int32 wid, int32 *history, int32 n_hist, int32 *n_used)
Implementation-specific function for querying raw language model probability.
int32(* score)(ngram_model_t *model, int32 wid, int32 *history, int32 n_hist, int32 *n_used)
Implementation-specific function for querying language model score.
void(* free)(ngram_model_t *model)
Implementation-specific function for freeing an ngram_model_t.
int(* apply_weights)(ngram_model_t *model, float32 lw, float32 wip)
Implementation-specific function for applying language model weights.
int32(* add_ug)(ngram_model_t *model, int32 wid, int32 lweight)
Implementation-specific function for adding unigrams.
void(* flush)(ngram_model_t *model)
Implementation-specific function for purging N-Gram cache.
Common implementation of ngram_model_t.
logmath_t * lmath
Log-math object.
struct ngram_class_s ** classes
Word class definitions.
int refcount
Reference count.
uint8 n
This is an n-gram model (1, 2, 3, ...).
int32 log_wip
Log of word insertion penalty.
int32 n_1g_alloc
Number of allocated word strings (for new word addition)
int32 * tmp_wids
Temporary array of word IDs for ngram_model_get_ngram()
int32 log_zero
Zero probability, cached here for quick lookup.
uint32 * n_counts
Counts for 1, 2, 3, ... grams.
int32 n_words
Number of actual word strings (NOT the same as the number of unigrams, due to class words).
hash_table_t * wid
Mapping of unigram names to word IDs.
float32 lw
Language model scaling factor.
uint8 writable
Are word strings writable?
uint8 flags
Any other flags we might care about (FIXME: Merge this and writable)
struct ngram_funcs_s * funcs
Implementation-specific methods.
uint8 n_classes
Number of classes (maximum 128)
char ** word_str
Unigram names.