pitsyn.c,v

lpc10-15为美军2400bps语音压缩标准的C语音源代码。

/* 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 = r__1 + .5f;
		if (uvpit != 0.f) {
		    ip = 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 = log((rco[j - 1] + 1) / (1 - rco[j - 1]));
			alrn = log((rc[j] + 1) / (1 - rc[j]));
			xxy = alro + prop * (alrn - alro);
			xxy = exp(xxy);
			rci[j + *nout * rci_dim1] = (xxy - 1) / (xxy + 1);
		    }
		    rmsi[*nout] = log(*rmso) + prop * (log(*rms) - log(*rmso));
		    rmsi[*nout] = 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_ */
@


1.1
log
@Initial revision
@
text
@d3 4
a6 1
$Log$
d11 1
a11 2
extern 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);
extern int initpitsyn_(void);
d25 4
a28 1
/* $Log: pitsyn.f,v $ */
d86 1
a86 1
/* Subroutine */ int pitsyn_0_(int n__, integer *order, integer *voice, 
d88 2
a89 1
	integer *ipiti, real *rmsi, real *rci, integer *nout, real *ratio)
d93 2
a94 2
    static real rmso = 1.f;
    static logical first = TRUE_;
d106 1
a106 1
    static integer jsamp;
d108 1
a108 1
    static integer ipito;
d111 1
a111 1
    static integer ivoico;
d113 1
a113 1
    static real rco[10];
d117 4
a120 1
/* $Log: config.fh,v $ */
d187 6
a192 3
    switch(n__) {
	case 1: goto L_initpitsyn;
	}
d197 2
a198 2
    if (rmso < 1.f) {
	rmso = 1.f;
d201 2
a202 2
    *ratio = *rms / (rmso + 8.f);
    if (first) {
d209 1
a209 1
	jsamp = *lframe - *nout * *pitch;
d230 1
a230 1
	first = FALSE_;
d233 2
a234 2
	lsamp = *lframe + jsamp;
	slope = (*pitch - ipito) / (real) lsamp;
d238 1
a238 1
	if (voice[1] == ivoico && voice[2] == voice[1]) {
d242 1
a242 1
		ipito = *pitch;
d244 1
a244 1
		    rmso = *rms;
d248 1
a248 1
	    slope = (*pitch - ipito) / (real) lsamp;
d251 2
a252 2
	    if (ivoico != 1) {
		if (ivoico == voice[1]) {
d263 2
a264 2
		rmsi[1] = rmso;
		rmsi[2] = rmso;
d273 1
a273 1
		ipito = *pitch;
d278 1
a278 1
		if (ivoico != voice[1]) {
d280 1
a280 1
		    lsamp = *lframe / 4 + jsamp;
d283 1
a283 1
		    lsamp = *lframe * 3 / 4 + jsamp;
d398 1
a398 1
		r__1 = ipito + slope * i__;
d427 1
a427 1
		    rmsi[*nout] = log(rmso) + prop * (log(*rms) - log(rmso));
d483 1
a483 1
	    lsamp = *lframe + jsamp;
d490 1
a490 1
	    rmso = *rms;
d498 1
a498 1
	jsamp = lsamp - jused;
d505 3
a507 3
	ivoico = voice[2];
	ipito = *pitch;
	rmso = *rms;
a513 5

L_initpitsyn:
    rmso = 1.f;
    first = TRUE_;
    return 0;
a514 16

/* Subroutine */ 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)
{
    return pitsyn_0_(0, order, voice, pitch, rms, rc, lframe, ivuv, ipiti, 
	    rmsi, rci, nout, ratio);
    }

/* Subroutine */ int initpitsyn_(void)
{
    return pitsyn_0_(1, (integer *)0, (integer *)0, (integer *)0, (real *)0, (
	    real *)0, (integer *)0, (integer *)0, (integer *)0, (real *)0, (
	    real *)0, (integer *)0, (real *)0);
    }

@