/*

 * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische

 * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for

 * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.

 */

#include <stdio.h>

#include  "gsm610_priv.h"

/*

 *  4.3 FIXED POINT IMPLEMENTATION OF THE RPE-LTP DECODER

 */

static void Postprocessing (

  struct gsm_state  * S,

  register int16_t    * s)

{

  register int    k ;

  register int16_t    msr = S->msr ;

  register int16_t    tmp ;

  for (k = 160 ; k-- ; s++)

  { tmp = GSM_MULT_R (msr, 28180) ;

    msr = GSM_ADD (*s, tmp) ;     /* Deemphasis        */

    *s = GSM_ADD (msr, msr) & 0xFFF8 ;  /* Truncation & Upscaling */

    }

  S->msr = msr ;

}

void Gsm_Decoder (

  struct gsm_state  * S,

  int16_t   * LARcr,  /* [0..7]   IN  */

  int16_t   * Ncr,    /* [0..3]     IN  */

  int16_t   * bcr,    /* [0..3]   IN  */

  int16_t   * Mcr,    /* [0..3]     IN  */

  int16_t   * xmaxcr, /* [0..3]   IN  */

  int16_t   * xMcr,   /* [0..13*4]    IN  */

  int16_t   * s)    /* [0..159]   OUT   */

{

  int   j, k ;

  int16_t   erp [40], wt [160] ;

  int16_t   *drp = S->dp0 + 120 ;

  for (j = 0 ; j <= 3 ; j++, xmaxcr++, bcr++, Ncr++, Mcr++, xMcr += 13)

  { Gsm_RPE_Decoding (/*-S,-*/ *xmaxcr, *Mcr, xMcr, erp) ;

    Gsm_Long_Term_Synthesis_Filtering (S, *Ncr, *bcr, erp, drp) ;

    for (k = 0 ; k <= 39 ; k++) wt [j * 40 + k] = drp [k] ;

    }

  Gsm_Short_Term_Synthesis_Filter (S, LARcr, wt, s) ;

  Postprocessing (S, s) ;

}