csub.c

this the source code of addio compression standard CELP. Also, it is optimizied for the execution sp

/**************************************************************************
*
* ROUTINE
*               csub
*
* FUNCTION
*               control routine to find optimal excitation 
*		(adaptive and stochastic code book searches)
*
* SYNOPSIS
*               subroutine csub(s, v, l, lp)
*
*   formal
*
*                       data    I/O
*       name            type    type    function
*       -------------------------------------------------------------------
*       s[l]            float	i       speech or residual segment
*       v[l]            float	o       optimum excitation vector
*       l               int	i       stochastic analysis frame size
*	lp		int	i	adaptive (pitch) analysis frame size
*
*   external
*                       data    I/O
*       name            type    type    function
*       -------------------------------------------------------------------
*	idb		int	i
*	no		int	i
*	nseg		int	i
*	sg		int	i
*	e0[]		float	i/o
*	fndex_e0_vid	int	i
*	fndpp_e0_vid	int	i
*	mxsw		int	i	modified excitation switch
*	
***************************************************************************
*
*  Global
*
*	SPECTRUM VARIABLES:
*	d2a	real	memory 1/A(z)
*	d2b	real	memory 1/A(z)
*	d3a	real	memory A(z)
*	d3b	real	memory A(z)
*	d4a	real	memory 1/A(z/gamma)
*	d4b	real	memory 1/A(z/gamma)
*
*	PITCH VARIABLES:
*	d1a	real	memory 1/P(z)
*	d1b	real	memory 1/P(z)
***************************************************************************
*
* CALLED BY
*
*       celp
*
* CALLS
*
*       confg   cbsearch   psearch   movefr   save_sg   setr
*
*	mescite1   mexcite2
*
**************************************************************************/
#include "ccsub.h"
float d1a[MAXPA], d1b[MAXPA], d2a[MAXNO+1], d2b[MAXNO+1], d3a[MAXNO+1], d3b[MAXNO+1];
float d4a[MAXNO+1], d4b[MAXNO+1];

float selec_ad[MAXLP];   /* selected pitch ex. from ad codebook by psearch*/

extern int idb, no, nseg, sg, mxsw;
extern float e0[MAXLP];


csub(s, v, l, lp)
int l, lp;
float s[], v[];

{
    register int i;
  /* *find the intial error without pitch VQ		 	 */

  setr(l, 0.0, e0);
  confg(s, l, d2a, d3a, d4a);
/*
  movefr(no + 1, d2b, d2a);
  movefr(no + 1, d3b, d3a);
  movefr(no + 1, d4b, d4a);
*/
  for (i = 0; i <= no; i++)
  {
    d2a[i] = d2b[i];
    d3a[i] = d3b[i];
    d4a[i] = d4b[i];
  }

  /* *find impulse response (h) of perceptual weighting filter   */
 
   impulse(l);
 

  /* *pitch (adaptive code book) search						 */

    psearch(l);

  /* *find initial error with pitch VQ				 */

  confg_ad(s, l, d1a, d2a, d3a, d4a);

  /* *stochastic code book search 				 */

  cbsearch(l, v);

  /* *update filter states 					 */

  movefr(l, v, e0);
  confg_cb(s, l, d1a, d2b, d3b, d4b);

/*
  movefr(no + 1, d2b, d2a);
  movefr(no + 1, d3b, d3a);
  movefr(no + 1, d4b, d4a);
*/
  for (i = 0; i <= no; i++)
  {
    d2a[i] = d2b[i];
    d3a[i] = d3b[i];
    d4a[i] = d4b[i];
  }

}