/* ----------------------------------------------------------- *//*                                                             *//*                          ___                                *//*                       |_| | |_/   SPEECH                    *//*                       | | | | \   RECOGNITION               *//*                       =========   SOFTWARE                  */ /*                                                             *//*                                                             *//* ----------------------------------------------------------- *//* developed at:                                               *//*                                                             *//*      Speech Vision and Robotics group                       *//*      Cambridge University Engineering Department            *//*      http://svr-www.eng.cam.ac.uk/                          *//*                                                             *//*      Entropic Cambridge Research Laboratory                 *//*      (now part of Microsoft)                                *//*                                                             *//* ----------------------------------------------------------- *//*         Copyright: Microsoft Corporation                    *//*          1995-2000 Redmond, Washington USA                  *//*                    http://www.microsoft.com                 *//*                                                             *//*          2001-2002 Cambridge University                     *//*                    Engineering Department                   *//*                                                             *//*   Use of this software is governed by a License Agreement   *//*    ** See the file License for the Conditions of Use  **    *//*    **     This banner notice must not be removed      **    *//*                                                             *//* ----------------------------------------------------------- *//*         File: HLM.h language model handling                 *//* ----------------------------------------------------------- *//* !HVER!HLM:   3.2 [CUED 09/12/02] */#ifndef _HLM_H_#define _HLM_H_#ifdef __cplusplusextern "C" {#endiftypedef enum { boNGram=1, matBigram, hlmModel } LMType;#define MAX_LMID 65534          /* Max number of words */typedef unsigned short lmId;    /* Type used by lm to id words  1..MAX_LMID */typedef unsigned short lmCnt;   /* Type used by lm to count wds 0..MAX_LMID */#define NSIZE 4                 /* Max length of ngram 2==bigram etc */typedef struct sentry {         /* HLM NGram probability */   lmId word;                   /* word id */   float prob;                  /* probability */} SEntry;typedef struct nentry {         /* HLM NGram history */   lmId word[NSIZE-1];          /* Word history representing this entry */   lmCnt nse;                   /* Number of ngrams for this entry */   float bowt;                  /* Back-off weight */   SEntry *se;                  /* Array[0..nse-1] of ngram probabilities */   struct nentry *link;         /* Next entry in hash table */   void *user;                  /* Accumulator or cache storage */} NEntry;typedef struct ngramlm {   int nsize;                   /* Unigram==1, Bigram==2, Trigram==3 */   unsigned int hashsize;       /* Size of hashtab (adjusted by lm counts) */   NEntry **hashtab;            /* Hash table for finding NEntries */   int counts[NSIZE+1];         /* Number of [n]grams */   int vocSize;                 /* Core LM size */   Vector unigrams;             /* Unigram probabilities */   LabId *wdlist;               /* Lookup table for words from lmId */   MemHeap *heap;               /* Pointer to heap */} NGramLM;typedef struct matbilm {   lmCnt numWords;              /* Number of words for language model */   Matrix bigMat;               /* Actual probs */   LabId *wdlist;               /* Lookup table for words from lmId */   MemHeap *heap;               /* Pointer to heap */} MatBiLM;typedef struct lmodel {   char *name;                  /* Name used for identifying lm */   LMType type;                 /* LM type */   LogFloat pen;                /* Word insertion penalty */   float scale;                 /* Language model scale */   union {      MatBiLM *matbi;      NGramLM *ngram;      void *hlmModel;   }   data;   MemHeap *heap;               /* Heap for allocating lm structs */} LModel;void InitLM(void);/*   Initialise the module*//* ---------------- Lower Level Routines ----------------- */NGramLM *CreateBoNGram(LModel *lm,int vocSize,int counts[NSIZE+1]);/*   Create backoff NGram language models with size defined by counts.    vocSize=number of words in vocabulary    counts[1]=number of unigrams    counts[2]=approximate number of bigrams    counts[3]=approximate number of trigrams               (approximate sizes are used to determine hash table size)*/MatBiLM *CreateMatBigram(LModel *lm,int nw);/*   Create matrix bigram language models of specified size.*/NEntry *GetNEntry(NGramLM *nglm,lmId ndx[NSIZE],Boolean create);/*   Find [create] ngram entry for word histories ...ndx[1] ndx[0].*//* --------------- Higher Level Routines ----------------- */float GetLMProb(LModel *lm, LabId prid[NSIZE], LabId wdid);/*   Calculate probability for wdid following prid*/LModel *ReadLModel(MemHeap *heap,char *fn);void WriteLModel(LModel *lm,char *fn,int flags);/*   Read/write language model from/to specified file.   Flags control format for writing.*/void ClearLModel(LModel *lm);/*    Clear LModel before deletion*/#ifndef NO_LAT_LMtypedef Ptr LMState;LogFloat LMTrans (LModel *lm, LMState src, LabId wdid, LMState *dest);#endif#ifdef __cplusplus}#endif#endif  /* _HLM_H_ *//* ---------------------- End of HLM.h ----------------------- */