4 Revision 1.16 2004/06/26 03:50:14 markster
5 Merge source cleanups (bug #1911)
7 Revision 1.15 2003/11/23 22:14:32 markster
8 Various warning cleanups
10 Revision 1.14 2003/02/12 13:59:15 matteo
11 mer feb 12 14:56:57 CET 2003
13 Revision 1.1.1.1 2003/02/12 13:59:15 matteo
14 mer feb 12 14:56:57 CET 2003
16 Revision 1.2 2000/01/05 08:20:40 markster
17 Some OSS fixes and a few lpc changes to make it actually work
19 * Revision 1.2 1996/08/20 20:45:00 jaf
20 * Removed all static local variables that were SAVE'd in the Fortran
21 * code, and put them in struct lpc10_encoder_state that is passed as an
24 * Removed init function, since all initialization is now done in
25 * init_lpc10_encoder_state().
27 * Revision 1.1 1996/08/19 22:30:14 jaf
33 /* -- translated by f2c (version 19951025).
34 You must link the resulting object file with the libraries:
35 -lf2c -lm (in that order)
40 #ifdef P_R_O_T_O_T_Y_P_E_S
41 extern int voicin_(integer
*vwin
, real
*inbuf
, real
*lpbuf
, integer
*buflim
, integer
*half
, real
*minamd
, real
*maxamd
, integer
*mintau
, real
*ivrc
, integer
*obound
, integer
*voibuf
, integer
*af
, struct lpc10_encoder_state
*st
);
42 /* comlen contrl_ 12 */
43 /*:ref: vparms_ 14 14 4 6 6 4 4 6 4 4 4 4 6 6 6 6 */
46 /* Common Block Declarations */
49 integer order
, lframe
;
53 #define contrl_1 contrl_
55 /****************************************************************************/
57 /* VOICIN Version 52 */
60 * Revision 1.16 2004/06/26 03:50:14 markster
61 * Merge source cleanups (bug #1911)
63 * Revision 1.15 2003/11/23 22:14:32 markster
64 * Various warning cleanups
66 * Revision 1.14 2003/02/12 13:59:15 matteo
67 * mer feb 12 14:56:57 CET 2003
69 * Revision 1.1.1.1 2003/02/12 13:59:15 matteo
70 * mer feb 12 14:56:57 CET 2003
72 * Revision 1.2 2000/01/05 08:20:40 markster
73 * Some OSS fixes and a few lpc changes to make it actually work
75 * Revision 1.2 1996/08/20 20:45:00 jaf
76 * Removed all static local variables that were SAVE'd in the Fortran
77 * code, and put them in struct lpc10_encoder_state that is passed as an
80 * Removed init function, since all initialization is now done in
81 * init_lpc10_encoder_state().
83 * Revision 1.1 1996/08/19 22:30:14 jaf
86 /* Revision 1.10 1996/03/29 17:59:14 jaf */
87 /* Avoided using VALUE(9), although it shouldn't affect the function of */
88 /* the code at all, because it was always multiplied by VDC(9,SNRL), */
89 /* which is 0 for all values of SNRL. Still, if VALUE(9) had an initial */
90 /* value of IEEE NaN, it might cause trouble (I don't know how IEEE */
91 /* defines Nan * 0. It should either be NaN or 0.) */
93 /* Revision 1.9 1996/03/29 17:54:46 jaf */
94 /* Added a few comments about the accesses made to argument array VOIBUF */
95 /* and the local saved array VOICE. */
97 /* Revision 1.8 1996/03/27 18:19:54 jaf */
98 /* Added an assignment to VSTATE that does not affect the function of the */
99 /* program at all. The only reason I put it in was so that the tracing */
100 /* statements at the end, when enabled, will print a consistent value for */
101 /* VSTATE when HALF .EQ. 1, rather than a garbage value that could change */
102 /* from one call to the next. */
104 /* Revision 1.7 1996/03/26 20:00:06 jaf */
105 /* Removed the inclusion of the file "vcomm.fh", and put its contents */
106 /* into this file. It was included nowhere else but here. */
108 /* Revision 1.6 1996/03/26 19:38:09 jaf */
109 /* Commented out trace statements. */
111 /* Revision 1.5 1996/03/19 20:43:45 jaf */
112 /* Added comments about which indices of OBOUND and VOIBUF can be */
113 /* accessed, and whether they are read or written. VOIBUF is fairly */
116 /* Revision 1.4 1996/03/19 15:00:58 jaf */
117 /* Moved the DATA statements for the *VDC* variables later, as it is */
118 /* apparently illegal to have DATA statements before local variable */
121 /* Revision 1.3 1996/03/19 00:10:49 jaf */
122 /* Heavily commented the local variables that are saved from one */
123 /* invocation to the next, and how the local variable FIRST is used to */
124 /* avoid the need to assign most of them initial values with DATA */
127 /* A few should be initialized, but aren't. I've guessed initial values */
128 /* for two of these, SFBUE and SLBUE, and I've convinced myself that for */
129 /* VOICE, the effects of uninitialized values will die out after 2 or 3 */
130 /* frame times. It would still be good to choose initial values for */
131 /* these, but I don't know what reasonable values would be (0 comes to */
134 /* Revision 1.2 1996/03/13 16:09:28 jaf */
135 /* Comments added explaining which of the local variables of this */
136 /* subroutine need to be saved from one invocation to the next, and which */
139 /* WARNING! Some of them that should are never given initial values in */
140 /* this code. Hopefully, Fortran 77 defines initial values for them, but */
141 /* even so, giving them explicit initial values is preferable. */
143 /* WARNING! VALUE(9) is used, but never assigned a value. It should */
144 /* probably be eliminated from the code. */
146 /* Revision 1.1 1996/02/07 14:50:28 jaf */
147 /* Initial revision */
150 /****************************************************************************/
152 /* Voicing Detection (VOICIN) makes voicing decisions for each half */
153 /* frame of input speech. Tentative voicing decisions are made two frames*/
154 /* in the future (2F) for each half frame. These decisions are carried */
155 /* through one frame in the future (1F) to the present (P) frame where */
156 /* they are examined and smoothed, resulting in the final voicing */
157 /* decisions for each half frame. */
158 /* The voicing parameter (signal measurement) column vector (VALUE) */
159 /* is based on a rectangular window of speech samples determined by the */
160 /* window placement algorithm. The voicing parameter vector contains the*/
161 /* AMDF windowed maximum-to-minimum ratio, the zero crossing rate, energy*/
162 /* measures, reflection coefficients, and prediction gains. The voicing */
163 /* window is placed to avoid contamination of the voicing parameter vector*/
164 /* with speech onsets. */
165 /* The input signal is then classified as unvoiced (including */
166 /* silence) or voiced. This decision is made by a linear discriminant */
167 /* function consisting of a dot product of the voicing decision */
168 /* coefficient (VDC) row vector with the measurement column vector */
169 /* (VALUE). The VDC vector is 2-dimensional, each row vector is optimized*/
170 /* for a particular signal-to-noise ratio (SNR). So, before the dot */
171 /* product is performed, the SNR is estimated to select the appropriate */
173 /* The smoothing algorithm is a modified median smoother. The */
174 /* voicing discriminant function is used by the smoother to determine how*/
175 /* strongly voiced or unvoiced a signal is. The smoothing is further */
176 /* modified if a speech onset and a voicing decision transition occur */
177 /* within one half frame. In this case, the voicing decision transition */
178 /* is extended to the speech onset. For transmission purposes, there are*/
179 /* constraints on the duration and transition of voicing decisions. The */
180 /* smoother takes these constraints into account. */
181 /* Finally, the energy estimates are updated along with the dither */
182 /* threshold used to calculate the zero crossing rate (ZC). */
185 /* VWIN - Voicing window limits */
186 /* The indices read of arrays VWIN, INBUF, LPBUF, and BUFLIM */
187 /* are the same as those read by subroutine VPARMS. */
188 /* INBUF - Input speech buffer */
189 /* LPBUF - Low-pass filtered speech buffer */
190 /* BUFLIM - INBUF and LPBUF limits */
191 /* HALF - Present analysis half frame number */
192 /* MINAMD - Minimum value of the AMDF */
193 /* MAXAMD - Maximum value of the AMDF */
194 /* MINTAU - Pointer to the lag of the minimum AMDF value */
195 /* IVRC(2) - Inverse filter's RC's */
196 /* Only index 2 of array IVRC read under normal operation. */
197 /* (Index 1 is also read when debugging is turned on.) */
198 /* OBOUND - Onset boundary descriptions */
199 /* Indices 1 through 3 read if (HALF .NE. 1), otherwise untouched.
201 /* AF - The analysis frame number */
203 /* VOIBUF(2,0:AF) - Buffer of voicing decisions */
204 /* Index (HALF,3) written. */
205 /* If (HALF .EQ. 1), skip down to "Read (HALF,3)" below. */
206 /* Indices (1,2), (2,1), (1,2), and (2,2) read. */
207 /* One of the following is then done: */
208 /* read (1,3) and possibly write (1,2) */
209 /* read (1,3) and write (1,2) or (2,2) */
211 /* write (2,1) or (1,2) */
212 /* read (1,0) and (1,3) and then write (2,2) or (1,1) */
213 /* no reads or writes on VOIBUF */
214 /* Finally, read (HALF,3) */
216 /* QS - Ratio of preemphasized to full-band energies */
217 /* RC1 - First reflection coefficient */
218 /* AR_B - Product of the causal forward and reverse pitch prediction gain
220 /* AR_F - Product of the noncausal forward and rev. pitch prediction gain
222 /* ZC - Zero crossing rate */
223 /* DITHER - Zero crossing threshold level */
224 /* MAXMIN - AMDF's 1 octave windowed maximum-to-minimum ratio */
225 /* MINPTR - Location of minimum AMDF value */
226 /* NVDC - Number of elements in each VDC vector */
227 /* NVDCL - Number of VDC vectors */
228 /* VDCL - SNR values corresponding to the set of VDC's */
229 /* VDC - 2-D voicing decision coefficient vector */
230 /* VALUE(9) - Voicing Parameters */
231 /* VOICE(2,3)- History of LDA results */
232 /* On every call when (HALF .EQ. 1), VOICE(*,I+1) is */
233 /* shifted back to VOICE(*,I), for I=1,2. */
234 /* VOICE(HALF,3) is written on every call. */
235 /* Depending on several conditions, one or more of */
236 /* (1,1), (1,2), (2,1), and (2,2) might then be read. */
237 /* LBE - Ratio of low-band instantaneous to average energies */
238 /* FBE - Ratio of full-band instantaneous to average energies */
239 /* LBVE - Low band voiced energy */
240 /* LBUE - Low band unvoiced energy */
241 /* FBVE - Full band voiced energy */
242 /* FBUE - Full band unvoiced energy */
243 /* OFBUE - Previous full-band unvoiced energy */
244 /* OLBUE - Previous low-band unvoiced energy */
245 /* REF - Reference energy for initialization and DITHER threshold */
246 /* SNR - Estimate of signal-to-noise ratio */
247 /* SNR2 - Estimate of low-band signal-to-noise ratio */
248 /* SNRL - SNR level number */
249 /* OT - Onset transition present */
250 /* VSTATE - Decimal interpretation of binary voicing classifications */
251 /* FIRST - First call flag */
253 /* This subroutine maintains local state from one call to the next. If */
254 /* you want to switch to using a new audio stream for this filter, or */
255 /* reinitialize its state for any other reason, call the ENTRY */
258 /* Subroutine */ int voicin_(integer
*vwin
, real
*inbuf
, real
*
259 lpbuf
, integer
*buflim
, integer
*half
, real
*minamd
, real
*maxamd
,
260 integer
*mintau
, real
*ivrc
, integer
*obound
, integer
*voibuf
,
261 integer
*af
, struct lpc10_encoder_state
*st
)
263 /* Initialized data */
266 static real vdc
[100] /* was [10][10] */ = { 0.f
,1714.f
,-110.f
,
267 334.f
,-4096.f
,-654.f
,3752.f
,3769.f
,0.f
,1181.f
,0.f
,874.f
,-97.f
,
268 300.f
,-4096.f
,-1021.f
,2451.f
,2527.f
,0.f
,-500.f
,0.f
,510.f
,-70.f
,
269 250.f
,-4096.f
,-1270.f
,2194.f
,2491.f
,0.f
,-1500.f
,0.f
,500.f
,-10.f
,
270 200.f
,-4096.f
,-1300.f
,2e3f
,2e3f
,0.f
,-2e3f
,0.f
,500.f
,0.f
,0.f
,
271 -4096.f
,-1300.f
,2e3f
,2e3f
,0.f
,-2500.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,
272 0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,
273 0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,
274 0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
};
275 static integer nvdcl
= 5;
276 static real vdcl
[10] = { 600.f
,450.f
,300.f
,200.f
,0.f
,0.f
,0.f
,0.f
,0.f
,0.f
}
279 /* System generated locals */
280 integer inbuf_offset
= 0, lpbuf_offset
= 0, i__1
, i__2
;
283 /* Builtin functions */
284 integer
i_nint(real
*);
285 double sqrt(doublereal
);
287 /* Local variables */
289 integer
*lbve
, *lbue
, *fbve
, *fbue
;
291 integer
*ofbue
, *sfbue
;
293 integer
*olbue
, *slbue
;
301 extern /* Subroutine */ int vparms_(integer
*, real
*, real
*, integer
*,
302 integer
*, real
*, integer
*, integer
*, integer
*, integer
*,
303 real
*, real
*, real
*, real
*);
308 /* Global Variables: */
311 * Revision 1.16 2004/06/26 03:50:14 markster
312 * Merge source cleanups (bug #1911)
314 * Revision 1.15 2003/11/23 22:14:32 markster
315 * Various warning cleanups
317 * Revision 1.14 2003/02/12 13:59:15 matteo
318 * mer feb 12 14:56:57 CET 2003
320 * Revision 1.1.1.1 2003/02/12 13:59:15 matteo
321 * mer feb 12 14:56:57 CET 2003
323 * Revision 1.2 2000/01/05 08:20:40 markster
324 * Some OSS fixes and a few lpc changes to make it actually work
326 * Revision 1.2 1996/08/20 20:45:00 jaf
327 * Removed all static local variables that were SAVE'd in the Fortran
328 * code, and put them in struct lpc10_encoder_state that is passed as an
331 * Removed init function, since all initialization is now done in
332 * init_lpc10_encoder_state().
334 * Revision 1.1 1996/08/19 22:30:14 jaf
337 /* Revision 1.3 1996/03/29 22:05:55 jaf */
338 /* Commented out the common block variables that are not needed by the */
339 /* embedded version. */
341 /* Revision 1.2 1996/03/26 19:34:50 jaf */
342 /* Added comments indicating which constants are not needed in an */
343 /* application that uses the LPC-10 coder. */
345 /* Revision 1.1 1996/02/07 14:44:09 jaf */
346 /* Initial revision */
348 /* LPC Processing control variables: */
350 /* *** Read-only: initialized in setup */
352 /* Files for Speech, Parameter, and Bitstream Input & Output, */
353 /* and message and debug outputs. */
355 /* Here are the only files which use these variables: */
357 /* lpcsim.f setup.f trans.f error.f vqsetup.f */
359 /* Many files which use fdebug are not listed, since it is only used in */
360 /* those other files conditionally, to print trace statements. */
361 /* integer fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
362 /* LPC order, Frame size, Quantization rate, Bits per frame, */
363 /* Error correction */
364 /* Subroutine SETUP is the only place where order is assigned a value, */
365 /* and that value is 10. It could increase efficiency 1% or so to */
366 /* declare order as a constant (i.e., a Fortran PARAMETER) instead of as
368 /* a variable in a COMMON block, since it is used in many places in the */
369 /* core of the coding and decoding routines. Actually, I take that back.
371 /* At least when compiling with f2c, the upper bound of DO loops is */
372 /* stored in a local variable before the DO loop begins, and then that is
374 /* compared against on each iteration. */
375 /* Similarly for lframe, which is given a value of MAXFRM in SETUP. */
376 /* Similarly for quant, which is given a value of 2400 in SETUP. quant */
377 /* is used in only a few places, and never in the core coding and */
378 /* decoding routines, so it could be eliminated entirely. */
379 /* nbits is similar to quant, and is given a value of 54 in SETUP. */
380 /* corrp is given a value of .TRUE. in SETUP, and is only used in the */
381 /* subroutines ENCODE and DECODE. It doesn't affect the speed of the */
382 /* coder significantly whether it is .TRUE. or .FALSE., or whether it is
384 /* a constant or a variable, since it is only examined once per frame. */
385 /* Leaving it as a variable that is set to .TRUE. seems like a good */
386 /* idea, since it does enable some error-correction capability for */
387 /* unvoiced frames, with no change in the coding rate, and no noticeable
389 /* quality difference in the decoded speech. */
390 /* integer quant, nbits */
391 /* *** Read/write: variables for debugging, not needed for LPC algorithm
394 /* Current frame, Unstable frames, Output clip count, Max onset buffer,
396 /* Debug listing detail level, Line count on listing page */
398 /* nframe is not needed for an embedded LPC10 at all. */
399 /* nunsfm is initialized to 0 in SETUP, and incremented in subroutine */
400 /* ERROR, which is only called from RCCHK. When LPC10 is embedded into */
401 /* an application, I would recommend removing the call to ERROR in RCCHK,
403 /* and remove ERROR and nunsfm completely. */
404 /* iclip is initialized to 0 in SETUP, and incremented in entry SWRITE in
406 /* sread.f. When LPC10 is embedded into an application, one might want */
407 /* to cause it to be incremented in a routine that takes the output of */
408 /* SYNTHS and sends it to an audio device. It could be optionally */
409 /* displayed, for those that might want to know what it is. */
410 /* maxosp is never initialized to 0 in SETUP, although it probably should
412 /* be, and it is updated in subroutine ANALYS. I doubt that its value */
413 /* would be of much interest to an application in which LPC10 is */
415 /* listl and lincnt are not needed for an embedded LPC10 at all. */
416 /* integer nframe, nunsfm, iclip, maxosp, listl, lincnt */
417 /* common /contrl/ fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
418 /* common /contrl/ quant, nbits */
419 /* common /contrl/ nframe, nunsfm, iclip, maxosp, listl, lincnt */
420 /* Parameters/constants */
421 /* Voicing coefficient and Linear Discriminant Analysis variables:
423 /* Max number of VDC's and VDC levels */
424 /* The following are not Fortran PARAMETER's, but they are */
425 /* initialized with DATA statements, and never modified. */
426 /* Actual number of VDC's and levels */
427 /* Local variables that need not be saved */
430 /* VALUE(1) through VALUE(8) are assigned values, but VALUE(9) */
431 /* never is. Yet VALUE(9) is read in the loop that begins "DO I =
433 /* 1, 9" below. I believe that this doesn't cause any problems in
435 /* this subroutine, because all VDC(9,*) array elements are 0, and
437 /* this is what is multiplied by VALUE(9) in all cases. Still, it
439 /* would save a multiplication to change the loop to "DO I = 1, 8".
444 /* VOICE, SFBUE, and SLBUE should be saved from one invocation to */
445 /* the next, but they are never given an initial value. */
447 /* Does Fortran 77 specify some default initial value, like 0, or */
448 /* is it undefined? If it is undefined, then this code should be */
449 /* corrected to specify an initial value. */
451 /* For VOICE, note that it is "shifted" in the statement that */
452 /* begins "IF (HALF .EQ. 1) THEN" below. Also, uninitialized */
453 /* values in the VOICE array can only affect entries in the VOIBUF
455 /* array that are for the same frame, or for an older frame. Thus
457 /* the effects of uninitialized values in VOICE cannot linger on */
458 /* for more than 2 or 3 frame times. */
460 /* For SFBUE and SLBUE, the effects of uninitialized values can */
461 /* linger on for many frame times, because their previous values */
462 /* are exponentially decayed. Thus it is more important to choose
464 /* initial values for these variables. I would guess that a */
465 /* reasonable initial value for SFBUE is REF/16, the same as used */
466 /* for FBUE and OFBUE. Similarly, SLBUE can be initialized to */
467 /* REF/32, the same as for LBUE and OLBUE. */
469 /* These guessed initial values should be validated by re-running */
470 /* the modified program on some audio samples. */
472 /* Declare and initialize filters: */
474 dither
= (&st
->dither
);
476 maxmin
= (&st
->maxmin
);
477 voice
= (&st
->voice
[0]);
482 ofbue
= (&st
->ofbue
);
483 olbue
= (&st
->olbue
);
484 sfbue
= (&st
->sfbue
);
485 slbue
= (&st
->slbue
);
487 /* Parameter adjustments */
495 inbuf_offset
= buflim
[1];
496 inbuf
-= inbuf_offset
;
499 lpbuf_offset
= buflim
[3];
500 lpbuf
-= lpbuf_offset
;
514 /* The following variables are saved from one invocation to the */
515 /* next, but are not initialized with DATA statements. This is */
516 /* acceptable, because FIRST is initialized ot .TRUE., and the */
517 /* first time that this subroutine is then called, they are all */
518 /* given initial values. */
521 /* LBVE, LBUE, FBVE, FBUE, OFBUE, OLBUE */
523 /* MAXMIN is initialized on the first call, assuming that HALF */
524 /* .EQ. 1 on first call. This is how ANALYS calls this subroutine.
527 /* Voicing Decision Parameter vector (* denotes zero coefficient): */
537 /* * LOG(LBE/LBVE) */
538 /* Define 2-D voicing decision coefficient vector according to the voicin
540 /* parameter order above. Each row (VDC vector) is optimized for a speci
542 /* SNR. The last element of the vector is the constant. */
543 /* E ZC RC1 Qs IVRC2 aRb aRf c */
545 /* The VOICE array contains the result of the linear discriminant functio
547 /* (analog values). The VOIBUF array contains the hard-limited binary
549 /* voicing decisions. The VOICE and VOIBUF arrays, according to FORTRAN
551 /* memory allocation, are addressed as: */
553 /* (half-frame number, future-frame number) */
555 /* | Past | Present | Future1 | Future2 | */
556 /* | 1,0 | 2,0 | 1,1 | 2,1 | 1,2 | 2,2 | 1,3 | 2,3 | ---> time */
558 /* Update linear discriminant function history each frame: */
564 *maxmin
= *maxamd
/ max(*minamd
,1.f
);
566 /* Calculate voicing parameters twice per frame: */
567 vparms_(&vwin
[1], &inbuf
[inbuf_offset
], &lpbuf
[lpbuf_offset
], &buflim
[1],
568 half
, dither
, mintau
, &zc
, &lbe
, &fbe
, &qs
, &rc1
, &ar_b__
, &
570 /* Estimate signal-to-noise ratio to select the appropriate VDC vector.
572 /* The SNR is estimated as the running average of the ratio of the */
573 /* running average full-band voiced energy to the running average */
574 /* full-band unvoiced energy. SNR filter has gain of 63. */
575 r__1
= (*snr
+ *fbve
/ (real
) max(*fbue
,1)) * 63 / 64.f
;
576 *snr
= (real
) i_nint(&r__1
);
577 snr2
= *snr
* *fbue
/ max(*lbue
,1);
578 /* Quantize SNR to SNRL according to VDCL thresholds. */
581 for (snrl
= 1; snrl
<= i__1
; ++snrl
) {
582 if (snr2
> vdcl
[snrl
- 1]) {
586 /* (Note: SNRL = NVDCL here) */
588 /* Linear discriminant voicing parameters: */
590 value
[1] = (real
) lbe
/ max(*lbve
,1);
591 value
[2] = (real
) zc
;
597 /* Evaluation of linear discriminant function: */
598 voice
[*half
+ 3] = vdc
[snrl
* 10 - 1];
599 for (i__
= 1; i__
<= 8; ++i__
) {
600 voice
[*half
+ 3] += vdc
[i__
+ snrl
* 10 - 11] * value
[i__
- 1];
602 /* Classify as voiced if discriminant > 0, otherwise unvoiced */
603 /* Voicing decision for current half-frame: 1 = Voiced; 0 = Unvoiced */
604 if (voice
[*half
+ 3] > 0.f
) {
605 voibuf
[*half
+ 6] = 1;
607 voibuf
[*half
+ 6] = 0;
609 /* Skip voicing decision smoothing in first half-frame: */
610 /* Give a value to VSTATE, so that trace statements below will print
612 /* a consistent value from one call to the next when HALF .EQ. 1. */
613 /* The value of VSTATE is not used for any other purpose when this is
620 /* Voicing decision smoothing rules (override of linear combination): */
622 /* Unvoiced half-frames: At least two in a row. */
623 /* -------------------- */
625 /* Voiced half-frames: At least two in a row in one frame. */
626 /* ------------------- Otherwise at least three in a row. */
627 /* (Due to the way transition frames are encoded) */
629 /* In many cases, the discriminant function determines how to smooth. */
630 /* In the following chart, the decisions marked with a * may be overridden
633 /* Voicing override of transitions at onsets: */
634 /* If a V/UV or UV/V voicing decision transition occurs within one-half
636 /* frame of an onset bounding a voicing window, then the transition is */
637 /* moved to occur at the onset. */
642 /* 0 0 0* 1 (If there is an onset there) */
643 /* 0 0 1* 0* (Based on 2F and discriminant distance) */
645 /* 0 1* 0 0 (Always) */
646 /* 0 1* 0* 1 (Based on discriminant distance) */
647 /* 0* 1 1 0* (Based on past, 2F, and discriminant distance) */
648 /* 0 1* 1 1 (If there is an onset there) */
649 /* 1 0* 0 0 (If there is an onset there) */
651 /* 1 0* 1* 0 (Based on discriminant distance) */
652 /* 1 0* 1 1 (Always) */
654 /* 1 1 0* 1* (Based on 2F and discriminant distance) */
655 /* 1 1 1* 0 (If there is an onset there) */
658 /* Determine if there is an onset transition between P and 1F. */
659 /* OT (Onset Transition) is true if there is an onset between */
660 /* P and 1F but not after 1F. */
661 ot
= ((obound
[1] & 2) != 0 || obound
[2] == 1) && (obound
[3] & 1) == 0;
662 /* Multi-way dispatch on voicing decision history: */
663 vstate
= (voibuf
[3] << 3) + (voibuf
[4] << 2) + (voibuf
[5] << 1) + voibuf
[
665 switch (vstate
+ 1) {
684 if (ot
&& voibuf
[7] == 1) {
689 if (voibuf
[7] == 0 || voice
[2] < -voice
[3]) {
699 if (voice
[1] < -voice
[2]) {
705 /* VOIBUF(2,0) must be 0 */
707 if (voibuf
[1] == 1 || voibuf
[7] == 1 || voice
[3] > voice
[0]) {
724 if (voice
[2] < -voice
[1]) {
734 if (voibuf
[7] == 0 && voice
[3] < -voice
[2]) {
741 if (ot
&& voibuf
[7] == 0) {
746 /* Now update parameters: */
747 /* ---------------------- */
749 /* During unvoiced half-frames, update the low band and full band unvoice
751 /* energy estimates (LBUE and FBUE) and also the zero crossing */
752 /* threshold (DITHER). (The input to the unvoiced energy filters is */
753 /* restricted to be less than 10dB above the previous inputs of the */
755 /* During voiced half-frames, update the low-pass (LBVE) and all-pass */
756 /* (FBVE) voiced energy estimates. */
757 if (voibuf
[*half
+ 6] == 0) {
759 i__1
= fbe
, i__2
= *ofbue
* 3;
760 r__1
= (*sfbue
* 63 + (min(i__1
,i__2
) << 3)) / 64.f
;
761 *sfbue
= i_nint(&r__1
);
765 i__1
= lbe
, i__2
= *olbue
* 3;
766 r__1
= (*slbue
* 63 + (min(i__1
,i__2
) << 3)) / 64.f
;
767 *slbue
= i_nint(&r__1
);
771 r__1
= (*lbve
* 63 + lbe
) / 64.f
;
772 *lbve
= i_nint(&r__1
);
773 r__1
= (*fbve
* 63 + fbe
) / 64.f
;
774 *fbve
= i_nint(&r__1
);
776 /* Set dither threshold to yield proper zero crossing rates in the */
777 /* presence of low frequency noise and low level signal input. */
778 /* NOTE: The divisor is a function of REF, the expected energies. */
781 r__2
= (real
)(sqrt((real
) (*lbue
* *lbve
)) * 64 / 3000);
782 r__1
= max(r__2
,1.f
);
783 *dither
= min(r__1
,20.f
);
784 /* Voicing decisions are returned in VOIBUF. */