ngrm_lm_0.cc

这是处理语音信号的程序

// file: ngrm_lm_0.cc
//

// isip include files
//
#include "ngram.h"
#include "ngram_constants.h"

// method: get_score_cc
//
// arguments:
//  int_4 num: (input) size of word array
//  Word** words: (input) pointers for words in list
//  
// return: a float_4 score represented by the ngram
//
// this method returns the score represented by the ngram
//
float_4 Ngram::get_score_cc(int_4 num_a, Word** words_a) {
  
  // define temporary variables used in function
  //
  logical_1 flag = ISIP_TRUE;
  float_4 score = NGRAM_NODE_DEFAULT_SCORE;
  Ngram_node** ngnode = (Ngram_node**)NULL;

  // get the correct ngram node
  //
  for (int_4 i = 0; i < num_a; i++) {

    // find the successive nodes
    //
    ngram_lists_d[i]->get_node_cc(words_a[i], ngnode);
    
    // if any of these ngram word sequences do not exist
    //
    if (ngnode == (Ngram_node**)NULL) {

      // set flag and break
      //
      flag = ISIP_FALSE;
      break;
    }
  } // end for loop

  // get lm score if ngram exists
  //
  if (flag == ISIP_TRUE) {
    score = (*ngnode)->get_lmscore_cc();
  }
  
  // else, use back-off to get ngram score
  //  
  else if (num_a - 1 > 0) {

    // get the backoff score
    //
    score = get_backoff_cc(num_a - 1, words_a);
    
    // add the lm score of the current word for a shorter history list
    //
    score += get_score_cc(num_a - 1, words_a + 1);
  }

  // otherwise this word sequence is invalid
  //
  else {
    fprintf(stdout, "The word sequence :: ");
    for (int_4 i = 0; i < num_a; i++) {
      fprintf(stdout, "%s ", words_a[i]->get_name_cc());
    }
    fprintf(stdout, ":: is not available in this language model\n");
  }
  
  // return score and exit gracefully
  //
  return score;
}