/* $Log: pitsyn.c,v $ Revision 1.1.1.1 2001/11/19 19:50:16 smorlat First cvs. Revision 1.1.1.1 2001/08/08 21:29:08 simon First import * 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 * */ #ifdef P_R_O_T_O_T_Y_P_E_S 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, struct lpc10_decoder_state *st); #endif /* -- translated by f2c (version 19951025). You must link the resulting object file with the libraries: -lf2c -lm (in that order) */ #include "f2c.h" /* ***************************************************************** */ /* PITSYN Version 53 */ /* $Log: pitsyn.c,v $ /* Revision 1.1.1.1 2001/11/19 19:50:16 smorlat /* First cvs. /* /* Revision 1.1.1.1 2001/08/08 21:29:08 simon /* First import /* * 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 1.2 1996/03/25 18:49:07 jaf */ /* Added commments about which indices of array arguments are read or */ /* written. */ /* Rearranged local variable declarations to indicate which need to be */ /* saved from one invocation to the next. Added entry INITPITSYN to */ /* reinitialize local state variables, if desired. */ /* Added lots of comments about proving that the maximum number of pitch */ /* periods (NOUT) that can be returned is 16. The call to STOP that */ /* could happen if NOUT got too large was removed as a result. */ /* Also proved that the total number of samples returned from N calls, */ /* each with identical values of LFRAME, will always be in the range */ /* N*LFRAME-MAXPIT+1 to N*LFRAME. */ /* Revision 1.1 1996/02/07 14:48:18 jaf */ /* Initial revision */ /* ***************************************************************** */ /* Synthesize a single pitch epoch */ /* Input: */ /* ORDER - Synthesis order (number of RC's) */ /* VOICE - Half frame voicing decisions */ /* Indices 1 through 2 read. */ /* LFRAME - Length of speech buffer */ /* Input/Output: */ /* PITCH - Pitch */ /* This value should be in the range MINPIT (20) to MAXPIT */ /* (156), inclusive. */ /* PITCH can be modified under some conditions. */ /* RMS - Energy (can be modified) */ /* RMS is changed to 1 if the value passed in is less than 1. */ /* RC - Reflection coefficients */ /* Indices 1 through ORDER can be temporarily overwritten with */ /* RCO, and then replaced with original values, under some */ /* conditions. */ /* Output: */ /* IVUV - Pitch epoch voicing decisions */ /* Indices (I) of IVUV, IPITI, and RMSI are written, */ /* and indices (J,I) of RCI are written, */ /* where I ranges from 1 to NOUT, and J ranges from 1 to ORDER. */ /* IPITI - Pitch epoch length */ /* RMSI - Pitch epoch energy */ /* RCI - Pitch epoch RC's */ /* NOUT - Number of pitch periods in this frame */ /* This is at least 0, at least 1 if MAXPIT .LT. LFRAME (this */ /* is currently true on every call), and can never be more than */ /* (LFRAME+MAXPIT-1)/PITCH, which is currently 16 with */ /* LFRAME=180, MAXPIT=156, and PITCH .GE. 20, as SYNTHS */ /* guarantees when it calls this subroutine. */ /* RATIO - Previous to present energy ratio */ /* Always assigned a value. */ /* 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, struct lpc10_decoder_state *st) { /* Initialized data */ real *rmso; logical *first; /* System generated locals */ integer rci_dim1, 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: pitsyn.c,v $ /* Revision 1.1.1.1 2001/11/19 19:50:16 smorlat /* First cvs. /* /* Revision 1.1.1.1 2001/08/08 21:29:08 simon /* First import /* * 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 = 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_ */

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