tbdm.c

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/*

$Log$
Revision 1.15 2004/06/26 03:50:14 markster
Merge source cleanups (bug #1911)

Revision 1.14 2003/02/12 13:59:15 matteo
mer feb 12 14:56:57 CET 2003

Revision 1.1.1.1 2003/02/12 13:59:15 matteo
mer feb 12 14:56:57 CET 2003

Revision 1.2 2000/01/05 08:20:40 markster
Some OSS fixes and a few lpc changes to make it actually work

 * Revision 1.1 1996/08/19 22:30:26 jaf
 * Initial revision
 *

*/

/* -- translated by f2c (version 19951025).
 You must link the resulting object file with the libraries:
 -lf2c -lm (in that order)
*/

#include "f2c.h"

#ifdef P_R_O_T_O_T_Y_P_E_S
extern int tbdm_(real *speech, integer *lpita, integer *tau, integer *ltau, real *amdf, integer *minptr, integer *maxptr, integer *mintau);
/*:ref: difmag_ 14 8 6 4 4 4 4 6 4 4 */
#endif

/* ********************************************************************** */

/* TBDM Version 49 */

/* $Log$
 * Revision 1.15 2004/06/26 03:50:14 markster
 * Merge source cleanups (bug #1911)
 *
 * Revision 1.14 2003/02/12 13:59:15 matteo
 * mer feb 12 14:56:57 CET 2003
 *
 * Revision 1.1.1.1 2003/02/12 13:59:15 matteo
 * mer feb 12 14:56:57 CET 2003
 *
 * Revision 1.2 2000/01/05 08:20:40 markster
 * Some OSS fixes and a few lpc changes to make it actually work
 *
 * Revision 1.1 1996/08/19 22:30:26 jaf
 * Initial revision
 * */
/* Revision 1.3 1996/03/18 22:14:00 jaf */
/* Just added a few comments about which array indices of the arguments */
/* are used, and mentioning that this subroutine has no local state. */

/* Revision 1.2 1996/03/13 14:48:37 jaf */
/* Comments added explaining that none of the local variables of this */
/* subroutine need to be saved from one invocation to the next. */

/* Revision 1.1 1996/02/07 14:49:54 jaf */
/* Initial revision */


/* ********************************************************************* */

/*TURBO DIFMAG: Compute High Resolution Average Magnitude Difference Function
*/

/* Note: There are several constants in here that appear to depend on a */
/* particular TAU table. That's not a problem for the LPC10 coder, but */
/* watch out if you change the contents of TAU in the subroutine ANALYS. */

/* Input: */
/* SPEECH - Low pass filtered speech */
/* Indices 1 through MAX+LPITA-1 are read, where: */
/* MAX = (TAU(LTAU)-TAU(1))/2+1 */
/* (If TAU(1) .LT. 39, then larger indices could be read */
/* by the last call to DIFMAG below.) */
/* LPITA - Length of speech buffer */
/* TAU - Table of lags, sorted in increasing order. */
/* Indices 1 through LTAU read. */
/* LTAU - Number of lag values to compute */
/* Output: */
/* AMDF - Average Magnitude Difference for each lag in TAU */
/* Indices 1 through LTAU written, and several might then be read.*/
/* MINPTR - Index of minimum AMDF value */
/* MAXPTR - Index of maximum AMDF value within +/- 1/2 octave of min */
/* MINTAU - Lag corresponding to minimum AMDF value */

/* This subroutine has no local state. */

/* Subroutine */ int tbdm_(real *speech, integer *lpita, integer *tau,
 integer *ltau, real *amdf, integer *minptr, integer *maxptr, integer *
 mintau)
{
 /* System generated locals */
 integer i__1, i__2, i__3, i__4;

 /* Local variables */
 real amdf2[6];
 integer minp2, ltau2, maxp2, i__;
 extern /* Subroutine */ int difmag_(real *, integer *, integer *, integer
 *, integer *, real *, integer *, integer *);
 integer minamd, ptr, tau2[6];

/* Arguments */
/* REAL SPEECH(LPITA+TAU(LTAU)), AMDF(LTAU) */
/* Stupid TOAST doesn't understand expressions */
/* Local variables that need not be saved */
/* Local state */
/* None */
/* Compute full AMDF using log spaced lags, find coarse minimum */
 /* Parameter adjustments */
 --speech;
 --amdf;
 --tau;

 /* Function Body */
 difmag_(&speech[1], lpita, &tau[1], ltau, &tau[*ltau], &amdf[1], minptr,
 maxptr);
 *mintau = tau[*minptr];
 minamd = (integer)amdf[*minptr];
/* Build table containing all lags within +/- 3 of the AMDF minimum */
/* excluding all that have already been computed */
 ltau2 = 0;
 ptr = *minptr - 2;
/* Computing MAX */
 i__1 = *mintau - 3;
/* Computing MIN */
 i__3 = *mintau + 3, i__4 = tau[*ltau] - 1;
 i__2 = min(i__3,i__4);
 for (i__ = max(i__1,41); i__ <= i__2; ++i__) {
 while(tau[ptr] < i__) {
 ++ptr;
 }
 if (tau[ptr] != i__) {
 ++ltau2;
 tau2[ltau2 - 1] = i__;
 }
 }
/* Compute AMDF of the new lags, if there are any, and choose one */
/* if it is better than the coarse minimum */
 if (ltau2 > 0) {
 difmag_(&speech[1], lpita, tau2, &ltau2, &tau[*ltau], amdf2, &minp2, &
 maxp2);
 if (amdf2[minp2 - 1] < (real) minamd) {
 *mintau = tau2[minp2 - 1];
 minamd = (integer)amdf2[minp2 - 1];
 }
 }
/* Check one octave up, if there are any lags not yet computed */
 if (*mintau >= 80) {
 i__ = *mintau / 2;
 if ((i__ & 1) == 0) {
 ltau2 = 2;
 tau2[0] = i__ - 1;
 tau2[1] = i__ + 1;
 } else {
 ltau2 = 1;
 tau2[0] = i__;
 }
 difmag_(&speech[1], lpita, tau2, &ltau2, &tau[*ltau], amdf2, &minp2, &
 maxp2);
 if (amdf2[minp2 - 1] < (real) minamd) {
 *mintau = tau2[minp2 - 1];
 minamd = (integer)amdf2[minp2 - 1];
 *minptr += -20;
 }
 }
/* Force minimum of the AMDF array to the high resolution minimum */
 amdf[*minptr] = (real) minamd;
/* Find maximum of AMDF within 1/2 octave of minimum */
/* Computing MAX */
 i__2 = *minptr - 5;
 *maxptr = max(i__2,1);
/* Computing MIN */
 i__1 = *minptr + 5;
 i__2 = min(i__1,*ltau);
 for (i__ = *maxptr + 1; i__ <= i__2; ++i__) {
 if (amdf[i__] > amdf[*maxptr]) {
 *maxptr = i__;
 }
 }
 return 0;
} /* tbdm_ */