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/* ITU-T G.729 Software Package Release 2 (November 2006) */ 
/* 
   ITU-T G.729 Annex C - Reference C code for floating point 
                         implementation of G.729 
                         Version 1.01 of 15.September.98 
*/ 
 
/* 
---------------------------------------------------------------------- 
                    COPYRIGHT NOTICE 
---------------------------------------------------------------------- 
   ITU-T G.729 Annex C ANSI C source code 
   Copyright (C) 1998, AT&T, France Telecom, NTT, University of 
   Sherbrooke.  All rights reserved. 
 
---------------------------------------------------------------------- 
*/ 
 
/* 
 File : PRED_LT3.C 
 Used for the floating point version of both 
 G.729 main body and G.729A 
*/ 
 
#include "typedef.h" 
#include "version.h" 
#ifdef VER_G729A 
 #include "ld8a.h" 
 #include "tab_ld8a.h" 
#else 
 #include "ld8k.h" 
 #include "tab_ld8k.h" 
#endif 
 
/*-------------------------------------------------------------------* 
 * Function  Pred_lt_3()                                             * 
 *           ~~~~~~~~~~~                                             * 
 *-------------------------------------------------------------------* 
 * Compute the result of long term prediction with fractional        * 
 * interpolation of resolution 1/3.                                  * 
 *                                                                   * 
 * On return exc[0..L_subfr-1] contains the interpolated signal      * 
 *   (adaptive codebook excitation)                                  * 
 *-------------------------------------------------------------------*/ 
 
void pred_lt_3(         /* Compute adaptive codebook                       */ 
  FLOAT exc[],          /* in/out: excitation vector, exc[0:l_sub-1] = out */ 
  int t0,               /* input : pitch lag                               */ 
  int frac,             /* input : Fraction of pitch lag (-1, 0, 1)  / 3   */ 
  int l_subfr           /* input : length of subframe.                     */ 
) 
{ 
 
  int   i, j, k; 
  FLOAT s, *x0, *x1, *x2, *c1, *c2; 
 
 
  x0 = &exc[-t0]; 
 
  frac = -frac; 
  if (frac < 0) { 
    frac += UP_SAMP; 
    x0--; 
  } 
 
  for (j=0; j