pitsyn.c File Reference

#include "f2c.h"

Include dependency graph for pitsyn.c:

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Functions
int	pitsyn_ (integer *order, integer *voice, integer *pitch, real *rms, real *rc, integer *lframe, integer *ivuv, integer *ipiti, real *rmsi, real *rci, integer *nout, real *ratio, struct lpc10_decoder_state *st)

Function Documentation

pitsyn_()

int pitsyn_	(	integer *	order,
		integer *	voice,
		integer *	pitch,
		real *	rms,
		real *	rc,
		integer *	lframe,
		integer *	ivuv,
		integer *	ipiti,
		real *	rmsi,
		real *	rci,
		integer *	nout,
		real *	ratio,
		struct lpc10_decoder_state *	st
	)

Definition at line 132 of file pitsyn.c.

References FALSE_, first, lpc10_decoder_state::first_pitsyn, lpc10_decoder_state::ipito, lpc10_decoder_state::ivoico, lpc10_decoder_state::jsamp, order, lpc10_decoder_state::rco, lpc10_decoder_state::rmso, and TRUE_.

Referenced by synths_().

{
    /* Initialized data */

    real *rmso;
    logical *first;

    /* System generated locals */
    integer rci_dim1 = 0, rci_offset, i__1, i__2;
    real r__1;

    /* Builtin functions */
    double log(doublereal), exp(doublereal);

    /* Local variables */
    real alrn, alro, yarc[10], prop;
    integer i__, j, vflag, jused, lsamp;
    integer *jsamp;
    real slope;
    integer *ipito;
    real uvpit;
    integer ip, nl, ivoice;
    integer *ivoico;
    integer istart;
    real *rco;
    real xxy;

/*       Arguments */
/* $Log$
 * Revision 1.16  2004/06/26 03:50:14  markster
 * Merge source cleanups (bug #1911)
 *
 * Revision 1.15  2003/11/23 22:14:32  markster
 * Various warning cleanups
 *
 * 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 08:20:39  markster
 * Some OSS fixes and a few lpc changes to make it actually work
 *
 * Revision 1.2  1996/08/20  20:40:12  jaf
 * Removed all static local variables that were SAVE'd in the Fortran
 * code, and put them in struct lpc10_decoder_state that is passed as an
 * argument.
 *
 * Removed init function, since all initialization is now done in
 * init_lpc10_decoder_state().
 *
 * Revision 1.1  1996/08/19  22:31:12  jaf
 * Initial revision
 * */
/* Revision 1.3  1996/03/29  22:03:47  jaf */
/* Removed definitions for any constants that were no longer used. */

/* Revision 1.2  1996/03/26  19:34:33  jaf */
/* Added comments indicating which constants are not needed in an */
/* application that uses the LPC-10 coder. */

/* Revision 1.1  1996/02/07  14:43:51  jaf */
/* Initial revision */

/*   LPC Configuration parameters: */
/* Frame size, Prediction order, Pitch period */
/*       Local variables that need not be saved */
/*       LSAMP is initialized in the IF (FIRST) THEN clause, but it is */
/*       not used the first time through, and it is given a value before
*/
/*       use whenever FIRST is .FALSE., so it appears unnecessary to */
/*       assign it a value when FIRST is .TRUE. */
/*       Local state */
/* FIRST  - .TRUE. only on first call to PITSYN. */
/* IVOICO - Previous VOICE(2) value. */
/* IPITO  - Previous PITCH value. */
/* RMSO   - Previous RMS value. */
/* RCO    - Previous RC values. */

/* JSAMP  - If this routine is called N times with identical values of */
/*          LFRAME, then the total length of all pitch periods returned */
/*          is always N*LFRAME-JSAMP, and JSAMP is always in the range 0
*/
/*          to MAXPIT-1 (see below for why this is so).  Thus JSAMP is */
/*          the number of samples "left over" from the previous call to */
/*          PITSYN, that haven't been "used" in a pitch period returned */
/*          from this subroutine.  Every time this subroutine is called,
*/
/*          it returns pitch periods with a total length of at most */
/*          LFRAME+JSAMP. */

/* IVOICO, IPITO, RCO, and JSAMP need not be assigned an initial value */
/* with a DATA statement, because they are always initialized on the */
/* first call to PITSYN. */

/* FIRST and RMSO should be initialized with DATA statements, because */
/* even on the first call, they are used before being initialized. */
    /* Parameter adjustments */
    if (rc) {
   --rc;
   }
    if (rci) {
   rci_dim1 = *order;
   rci_offset = rci_dim1 + 1;
   rci -= rci_offset;
   }
    if (voice) {
   --voice;
   }
    if (ivuv) {
   --ivuv;
   }
    if (ipiti) {
   --ipiti;
   }
    if (rmsi) {
   --rmsi;
   }

    /* Function Body */
    ivoico = &(st->ivoico);
    ipito = &(st->ipito);
    rmso = &(st->rmso);
    rco = &(st->rco[0]);
    jsamp = &(st->jsamp);
    first = &(st->first_pitsyn);

    if (*rms < 1.f) {
   *rms = 1.f;
    }
    if (*rmso < 1.f) {
   *rmso = 1.f;
    }
    uvpit = 0.f;
    *ratio = *rms / (*rmso + 8.f);
    if (*first) {
   lsamp = 0;
   ivoice = voice[2];
   if (ivoice == 0) {
       *pitch = *lframe / 4;
   }
   *nout = *lframe / *pitch;
   *jsamp = *lframe - *nout * *pitch;

/*          SYNTHS only calls this subroutine with PITCH in the range
20 */
/*          to 156.  LFRAME = MAXFRM = 180, so NOUT is somewhere in th
e */
/*          range 1 to 9. */

/*          JSAMP is "LFRAME mod PITCH", so it is in the range 0 to */
/*          (PITCH-1), or 0 to MAXPIT-1=155, after the first call. */

   i__1 = *nout;
   for (i__ = 1; i__ <= i__1; ++i__) {
       i__2 = *order;
       for (j = 1; j <= i__2; ++j) {
      rci[j + i__ * rci_dim1] = rc[j];
       }
       ivuv[i__] = ivoice;
       ipiti[i__] = *pitch;
       rmsi[i__] = *rms;
   }
   *first = FALSE_;
    } else {
   vflag = 0;
   lsamp = *lframe + *jsamp;
   slope = (*pitch - *ipito) / (real) lsamp;
   *nout = 0;
   jused = 0;
   istart = 1;
   if (voice[1] == *ivoico && voice[2] == voice[1]) {
       if (voice[2] == 0) {
/* SSUV - -   0  ,  0  ,  0 */
      *pitch = *lframe / 4;
      *ipito = *pitch;
      if (*ratio > 8.f) {
          *rmso = *rms;
      }
       }
/* SSVC - -   1  ,  1  ,  1 */
       slope = (*pitch - *ipito) / (real) lsamp;
       ivoice = voice[2];
   } else {
       if (*ivoico != 1) {
      if (*ivoico == voice[1]) {
/* UV2VC2 - -  0  ,  0  ,  1 */
          nl = lsamp - *lframe / 4;
      } else {
/* UV2VC1 - -  0  ,  1  ,  1 */
          nl = lsamp - *lframe * 3 / 4;
      }
      ipiti[1] = nl / 2;
      ipiti[2] = nl - ipiti[1];
      ivuv[1] = 0;
      ivuv[2] = 0;
      rmsi[1] = *rmso;
      rmsi[2] = *rmso;
      i__1 = *order;
      for (i__ = 1; i__ <= i__1; ++i__) {
          rci[i__ + rci_dim1] = rco[i__ - 1];
          rci[i__ + (rci_dim1 << 1)] = rco[i__ - 1];
          rco[i__ - 1] = rc[i__];
      }
      slope = 0.f;
      *nout = 2;
      *ipito = *pitch;
      jused = nl;
      istart = nl + 1;
      ivoice = 1;
       } else {
      if (*ivoico != voice[1]) {
/* VC2UV1 - -   1  ,  0  ,  0 */
          lsamp = *lframe / 4 + *jsamp;
      } else {
/* VC2UV2 - -   1  ,  1  ,  0 */
          lsamp = *lframe * 3 / 4 + *jsamp;
      }
      i__1 = *order;
      for (i__ = 1; i__ <= i__1; ++i__) {
          yarc[i__ - 1] = rc[i__];
          rc[i__] = rco[i__ - 1];
      }
      ivoice = 1;
      slope = 0.f;
      vflag = 1;
       }
   }
/* Here is the value of most variables that are used below, depending
on */
/* the values of IVOICO, VOICE(1), and VOICE(2).  VOICE(1) and VOICE(2
) */
/* are input arguments, and IVOICO is the value of VOICE(2) on the */
/* previous call (see notes for the IF (NOUT .NE. 0) statement near th
e */
/* end).  Each of these three values is either 0 or 1.  These three */
/* values below are given as 3-bit long strings, in the order IVOICO,
*/
/* VOICE(1), and VOICE(2).  It appears that the code above assumes tha
t */
/* the bit sequences 010 and 101 never occur, but I wonder whether a
*/
/* large enough number of bit errors in the channel could cause such a
 */
/* thing to happen, and if so, could that cause NOUT to ever go over 1
1? */

/* Note that all of the 180 values in the table are really LFRAME, but
 */
/* 180 has fewer characters, and it makes the table a little more */
/* concrete.  If LFRAME is ever changed, keep this in mind.  Similarly
, */
/* 135's are 3*LFRAME/4, and 45's are LFRAME/4.  If LFRAME is not a */
/* multiple of 4, then the 135 for NL-JSAMP is actually LFRAME-LFRAME/
4, */
/* and the 45 for NL-JSAMP is actually LFRAME-3*LFRAME/4. */

/* Note that LSAMP-JSAMP is given as the variable.  This was just for
*/
/* brevity, to avoid adding "+JSAMP" to all of the column entries. */
/* Similarly for NL-JSAMP. */

/* Variable    | 000  001    011,010  111       110       100,101 */
/* ------------+-------------------------------------------------- */
/* ISTART      | 1    NL+1   NL+1     1         1         1 */
/* LSAMP-JSAMP | 180  180    180      180       135       45 */
/* IPITO       | 45   PITCH  PITCH    oldPITCH  oldPITCH  oldPITCH */
/* SLOPE       | 0    0      0        seebelow  0         0 */
/* JUSED       | 0    NL     NL       0         0         0 */
/* PITCH       | 45   PITCH  PITCH    PITCH     PITCH     PITCH */
/* NL-JSAMP    | --   135    45       --        --        -- */
/* VFLAG       | 0    0      0        0         1         1 */
/* NOUT        | 0    2      2        0         0         0 */
/* IVOICE      | 0    1      1        1         1         1 */

/* while_loop  | once once   once     once      twice     twice */

/* ISTART      | --   --     --       --        JUSED+1   JUSED+1 */
/* LSAMP-JSAMP | --   --     --       --        180       180 */
/* IPITO       | --   --     --       --        oldPITCH  oldPITCH */
/* SLOPE       | --   --     --       --        0         0 */
/* JUSED       | --   --     --       --        ??        ?? */
/* PITCH       | --   --     --       --        PITCH     PITCH */
/* NL-JSAMP    | --   --     --       --        --        -- */
/* VFLAG       | --   --     --       --        0         0 */
/* NOUT        | --   --     --       --        ??        ?? */
/* IVOICE      | --   --     --       --        0         0 */


/* UVPIT is always 0.0 on the first pass through the DO WHILE (.TRUE.)
 */
/* loop below. */

/* The only possible non-0 value of SLOPE (in column 111) is */
/* (PITCH-IPITO)/FLOAT(LSAMP) */

/* Column 101 is identical to 100.  Any good properties we can prove
*/
/* for 100 will also hold for 101.  Similarly for 010 and 011. */

/* SYNTHS calls this subroutine with PITCH restricted to the range 20
to */
/* 156.  IPITO is similarly restricted to this range, after the first
*/
/* call.  IP below is also restricted to this range, given the */
/* definitions of IPITO, SLOPE, UVPIT, and that I is in the range ISTA
RT */
/* to LSAMP. */

   while(TRUE_) {

/*             JUSED is the total length of all pitch periods curr
ently */
/*             in the output arrays, in samples. */

/*             An invariant of the DO I = ISTART,LSAMP loop below,
 under */
/*             the condition that IP is always in the range 1 thro
ugh */
/*             MAXPIT, is: */

/*             (I - MAXPIT) .LE. JUSED .LE. (I-1) */

/*             Note that the final value of I is LSAMP+1, so that
after */
/*             the DO loop is complete, we know: */

/*             (LSAMP - MAXPIT + 1) .LE. JUSED .LE. LSAMP */

       i__1 = lsamp;
       for (i__ = istart; i__ <= i__1; ++i__) {
      r__1 = *ipito + slope * i__;
      ip = (integer)(r__1 + .5f);
      if (uvpit != 0.f) {
          ip = (integer)uvpit;
      }
      if (ip <= i__ - jused) {
          ++(*nout);

/*                   The following check is no longer nece
ssary, now that */
/*                   we can prove that NOUT will never go
over 16. */

/*           IF (NOUT .GT. 16) STOP 'PITSYN: too many epochs'
*/

          ipiti[*nout] = ip;
          *pitch = ip;
          ivuv[*nout] = ivoice;
          jused += ip;
          prop = (jused - ip / 2) / (real) lsamp;
          i__2 = *order;
          for (j = 1; j <= i__2; ++j) {
         alro = (real)log((rco[j - 1] + 1) / (1 - rco[j - 1]));
         alrn = (real)log((rc[j] + 1) / (1 - rc[j]));
         xxy = alro + prop * (alrn - alro);
         xxy = (real)exp(xxy);
         rci[j + *nout * rci_dim1] = (xxy - 1) / (xxy + 1);
          }
          rmsi[*nout] = (real)(log(*rmso) + prop * (log(*rms) - log(*rmso)));
          rmsi[*nout] = (real)exp(rmsi[*nout]);
      }
       }
       if (vflag != 1) {
      goto L100;
       }

/*             I want to prove what range UVPIT must lie in after
the */
/*             assignments to it below.  To do this, I must determ
ine */
/*             what range (LSAMP-ISTART) must lie in, after the */
/*             assignments to ISTART and LSAMP below. */

/*             Let oldLSAMP be the value of LSAMP at this point in
 the */
/*             execution.  This is 135+JSAMP in state 110, or 45+J
SAMP in */
/*             states 100 or 101. */

/*             Given the loop invariant on JUSED above, we know th
at: */

/*             (oldLSAMP - MAXPIT + 1) .LE. JUSED .LE. oldLSAMP */

/*             ISTART is one more than this. */

/*             Let newLSAMP be the value assigned to LSAMP below.
 This */
/*             is 180+JSAMP.  Thus (newLSAMP-oldLSAMP) is either 4
5 or */
/*             135, depending on the state. */

/*             Thus, the range of newLSAMP-ISTART is: */

/*             (newLSAMP-(oldLSAMP+1)) .LE. newLSAMP-ISTART */
/*             .LE. (newLSAMP-(oldLSAMP - MAXPIT + 2)) */

/*             or: */

/*             46 .LE. newLSAMP-ISTART .LE. 133+MAXPIT .EQ. 289 */

/*             Therefore, UVPIT is in the range 23 to 144 after th
e first */
/*             assignment to UVPIT below, and after the conditiona
l */
/*             assignment, it is in the range 23 to 90. */

/*             The important thing is that it is in the range 20 t
o 156, */
/*             so that in the loop above, IP is always in this ran
ge. */

       vflag = 0;
       istart = jused + 1;
       lsamp = *lframe + *jsamp;
       slope = 0.f;
       ivoice = 0;
       uvpit = (real) ((lsamp - istart) / 2);
       if (uvpit > 90.f) {
      uvpit /= 2;
       }
       *rmso = *rms;
       i__1 = *order;
       for (i__ = 1; i__ <= i__1; ++i__) {
      rc[i__] = yarc[i__ - 1];
      rco[i__ - 1] = yarc[i__ - 1];
       }
   }
L100:
   *jsamp = lsamp - jused;
    }
/*       Given that the maximum pitch period MAXPIT .LT. LFRAME (this is
*/
/*       currently true on every call, since SYNTHS always sets */
/*       LFRAME=180), NOUT will always be .GE. 1 at this point. */
    if (*nout != 0) {
   *ivoico = voice[2];
   *ipito = *pitch;
   *rmso = *rms;
   i__1 = *order;
   for (i__ = 1; i__ <= i__1; ++i__) {
       rco[i__ - 1] = rc[i__];
   }
    }
    return 0;
} /* pitsyn_ */