util.c

关于AMR-WB+语音压缩编码的实现代码

#include <math.h>
#include "../include/amr_plus.h"
/*-----------------------------------------------------------*
 * procedure set_zero                                        *
 * ~~~~~~~~~~~~~~~~~~                                        *
 * Set a vector x[] of dimension n to zero.                  *
 *-----------------------------------------------------------*/
void set_zero(float *x, int n)
{
  int i;
  for (i = 0; i < n; i++) {
    x[i] = 0.0;
  }
  return;
}
/*-----------------------------------------------------------*
 * procedure   mvr2r:                                        *
 *             ~~~~~~                                        *
 *  Transfer the contents of the vector x[] (real format)    *
 *  to the vector y[] (real format)                          *
 *-----------------------------------------------------------*/
void mvr2r(
  float x[],       /* input : input vector  */
  float y[],       /* output: output vector */
  int n            /* input : vector size   */
)
{
  int i;
  for (i = 0; i < n; i++) {
   y[i] = x[i];
  }
  return;
}
/*-----------------------------------------------------------*
 * procedure   mvs2s:                                        *
 *             ~~~~~~                                        *
 *  Transfer the contents of the vector x[] (short format)   *
 *  to the vector y[] (short format)                         *
 *-----------------------------------------------------------*/
void mvs2s(
  short x[],       /* input : input vector  */
  short y[],       /* output: output vector */
  int n            /* input : vector size   */
)
{
  int i;
  for (i = 0; i < n; i++) {
    y[i] = x[i];
  }
  return;
}
/*-----------------------------------------------------------*
 * procedure   mvs2s:                                        *
 *             ~~~~~~                                        *
 *  Transfer the contents of the vector x[] (short format)   *
 *  to the vector y[] (short format)                         *
 *-----------------------------------------------------------*/
void mvi2i(
  int x[],         /* input : input vector  */
  int y[],         /* output: output vector */
  int n            /* input : vector size   */
)
{
  int i;
  for (i = 0; i < n; i++) {
    y[i] = x[i];
  }
  return;
}
/*-----------------------------------------------------------*
 * procedure   mvr2s:                                        *
 *             ~~~~~~                                        *
 *  Transfer the contents of the vector x[] (real format)    *
 *  to the vector y[] (short format)                         *
 *-----------------------------------------------------------*/
void mvr2s(
  float x[],       /* input : input vector  */
  short y[],       /* output: output vector */
  int n            /* input : vector size   */
)
{
  int i;
  float temp;
  for (i = 0; i < n; i++) {
    temp = x[i];
    temp = (float)floor(temp + 0.5);
    if (temp >  32767.0 ) temp =  32767.0;
    if (temp < -32768.0 ) temp = -32768.0;
    y[i] = (short)temp;
  }
  return;
}
/*-----------------------------------------------------------*
 * procedure   mvs2r:                                        *
 *             ~~~~~~                                        *
 *  Transfer the contents of the vector x[] (short format)   *
 *  to the vector y[] (reel format)                          *
 *-----------------------------------------------------------*/
void mvs2r(
  short x[],       /* input : input vector  */
  float y[],       /* output: output vector */
  int n            /* input : vector size   */
)
{
  int i;
  for (i = 0; i < n; i++) {
    y[i] = (float)x[i];
  }
  return;
}

int get_nb_bits(short extension, short mode, short st_mode)
{
   int nb_bits;

   if (mode != 14 && mode != 15) /*prevent reading outside NBITS_CORE_AMR_WB buffer */
   {
     if(extension != 0)
     {
       nb_bits = NBITS_CORE[mode] + NBITS_BWE;
       if (st_mode >= 0)
       {
          nb_bits += (StereoNbits[st_mode] + NBITS_BWE);
       }
     }
     else
     {
        nb_bits = NBITS_CORE_AMR_WB[mode];
     }
   }
   else
   {
     nb_bits = 0;   
   }


   return nb_bits;
}
/*----------------------------------------------------------*
 * procedure pessimize:                                     *
 * A fake don-nothing routine to break program flow and     *
 * prevent optimisation                                     *
 *----------------------------------------------------------*/
void pessimize()
{
}