lpc10/voicin.c

   1 /*
   2
   3  * Revision 1.2  1996/08/20  20:45:00  jaf
   4  * Removed all static local variables that were SAVE'd in the Fortran
   5  * code, and put them in struct lpc10_encoder_state that is passed as an
   6  * argument.
   7  *
   8  * Removed init function, since all initialization is now done in
   9  * init_lpc10_encoder_state().
  10  *
  11  * Revision 1.1  1996/08/19  22:30:14  jaf
  12  * Initial revision
  13  *
  14
  15 */
  16
  17 /*  -- translated by f2c (version 19951025).
  18    You must link the resulting object file with the libraries:
  19         -lf2c -lm   (in that order)
  20 */
  21
  22 #include "f2c.h"
  23
  24 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);
  25
  26 /* Common Block Declarations */
  27
  28 extern struct {
  29     integer order, lframe;
  30     logical corrp;
  31 } contrl_;
  32
  33 #define contrl_1 contrl_
  34
  35 /****************************************************************************/
  36
  37 /*      VOICIN Version 52 */
  38
  39 /*
  40  * Revision 1.2  1996/08/20  20:45:00  jaf
  41  * Removed all static local variables that were SAVE'd in the Fortran
  42  * code, and put them in struct lpc10_encoder_state that is passed as an
  43  * argument.
  44  *
  45  * Removed init function, since all initialization is now done in
  46  * init_lpc10_encoder_state().
  47  *
  48  * Revision 1.1  1996/08/19  22:30:14  jaf
  49  * Initial revision
  50  * */
  51 /* Revision 1.10  1996/03/29  17:59:14  jaf */
  52 /* Avoided using VALUE(9), although it shouldn't affect the function of */
  53 /* the code at all, because it was always multiplied by VDC(9,SNRL), */
  54 /* which is 0 for all values of SNRL.  Still, if VALUE(9) had an initial */
  55 /* value of IEEE NaN, it might cause trouble (I don't know how IEEE */
  56 /* defines Nan * 0.  It should either be NaN or 0.) */
  57
  58 /* Revision 1.9  1996/03/29  17:54:46  jaf */
  59 /* Added a few comments about the accesses made to argument array VOIBUF */
  60 /* and the local saved array VOICE. */
  61
  62 /* Revision 1.8  1996/03/27  18:19:54  jaf */
  63 /* Added an assignment to VSTATE that does not affect the function of the */
  64 /* program at all.  The only reason I put it in was so that the tracing */
  65 /* statements at the end, when enabled, will print a consistent value for */
  66 /* VSTATE when HALF .EQ. 1, rather than a garbage value that could change */
  67 /* from one call to the next. */
  68
  69 /* Revision 1.7  1996/03/26  20:00:06  jaf */
  70 /* Removed the inclusion of the file "vcomm.fh", and put its contents */
  71 /* into this file.  It was included nowhere else but here. */
  72
  73 /* Revision 1.6  1996/03/26  19:38:09  jaf */
  74 /* Commented out trace statements. */
  75
  76 /* Revision 1.5  1996/03/19  20:43:45  jaf */
  77 /* Added comments about which indices of OBOUND and VOIBUF can be */
  78 /* accessed, and whether they are read or written.  VOIBUF is fairly */
  79 /* messy. */
  80
  81 /* Revision 1.4  1996/03/19  15:00:58  jaf */
  82 /* Moved the DATA statements for the *VDC* variables later, as it is */
  83 /* apparently illegal to have DATA statements before local variable */
  84 /* declarations. */
  85
  86 /* Revision 1.3  1996/03/19  00:10:49  jaf */
  87 /* Heavily commented the local variables that are saved from one */
  88 /* invocation to the next, and how the local variable FIRST is used to */
  89 /* avoid the need to assign most of them initial values with DATA */
  90 /* statements. */
  91
  92 /* A few should be initialized, but aren't.  I've guessed initial values */
  93 /* for two of these, SFBUE and SLBUE, and I've convinced myself that for */
  94 /* VOICE, the effects of uninitialized values will die out after 2 or 3 */
  95 /* frame times.  It would still be good to choose initial values for */
  96 /* these, but I don't know what reasonable values would be (0 comes to */
  97 /* mind). */
  98
  99 /* Revision 1.2  1996/03/13  16:09:28  jaf */
 100 /* Comments added explaining which of the local variables of this */
 101 /* subroutine need to be saved from one invocation to the next, and which */
 102 /* do not. */
 103
 104 /* WARNING!  Some of them that should are never given initial values in */
 105 /* this code.  Hopefully, Fortran 77 defines initial values for them, but */
 106 /* even so, giving them explicit initial values is preferable. */
 107
 108 /* WARNING!  VALUE(9) is used, but never assigned a value.  It should */
 109 /* probably be eliminated from the code. */
 110
 111 /* Revision 1.1  1996/02/07 14:50:28  jaf */
 112 /* Initial revision */
 113
 114
 115 /****************************************************************************/
 116
 117 /*        Voicing Detection (VOICIN) makes voicing decisions for each half */
 118 /*  frame of input speech.  Tentative voicing decisions are made two frames*/
 119 /*   in the future (2F) for each half frame.  These decisions are carried */
 120 /*   through one frame in the future (1F) to the present (P) frame where */
 121 /*   they are examined and smoothed, resulting in the final voicing */
 122 /*   decisions for each half frame. */
 123 /*        The voicing parameter (signal measurement) column vector (VALUE) */
 124 /*   is based on a rectangular window of speech samples determined by the */
 125 /*  window placement algorithm.  The voicing parameter vector contains the*/
 126 /*  AMDF windowed maximum-to-minimum ratio, the zero crossing rate, energy*/
 127 /*   measures, reflection coefficients, and prediction gains.  The voicing */
 128 /*  window is placed to avoid contamination of the voicing parameter vector*/
 129 /*   with speech onsets. */
 130 /*        The input signal is then classified as unvoiced (including */
 131 /*   silence) or voiced.  This decision is made by a linear discriminant */
 132 /*   function consisting of a dot product of the voicing decision */
 133 /*   coefficient (VDC) row vector with the measurement column vector */
 134 /*  (VALUE).  The VDC vector is 2-dimensional, each row vector is optimized*/
 135 /*   for a particular signal-to-noise ratio (SNR).  So, before the dot */
 136 /*   product is performed, the SNR is estimated to select the appropriate */
 137 /*   VDC vector. */
 138 /*        The smoothing algorithm is a modified median smoother.  The */
 139 /*  voicing discriminant function is used by the smoother to determine how*/
 140 /*   strongly voiced or unvoiced a signal is.  The smoothing is further */
 141 /*   modified if a speech onset and a voicing decision transition occur */
 142 /*   within one half frame.  In this case, the voicing decision transition */
 143 /*  is extended to the speech onset.  For transmission purposes, there are*/
 144 /*   constraints on the duration and transition of voicing decisions.  The */
 145 /*   smoother takes these constraints into account. */
 146 /*        Finally, the energy estimates are updated along with the dither */
 147 /*   threshold used to calculate the zero crossing rate (ZC). */
 148
 149 /* Inputs: */
 150 /*  VWIN      - Voicing window limits */
 151 /*              The indices read of arrays VWIN, INBUF, LPBUF, and BUFLIM */
 152 /*              are the same as those read by subroutine VPARMS. */
 153 /*  INBUF     - Input speech buffer */
 154 /*  LPBUF     - Low-pass filtered speech buffer */
 155 /*  BUFLIM    - INBUF and LPBUF limits */
 156 /*  HALF      - Present analysis half frame number */
 157 /*  MINAMD    - Minimum value of the AMDF */
 158 /*  MAXAMD    - Maximum value of the AMDF */
 159 /*  MINTAU    - Pointer to the lag of the minimum AMDF value */
 160 /*  IVRC(2)   - Inverse filter's RC's */
 161 /*              Only index 2 of array IVRC read under normal operation. */
 162 /*              (Index 1 is also read when debugging is turned on.) */
 163 /*  OBOUND    - Onset boundary descriptions */
 164 /*             Indices 1 through 3 read if (HALF .NE. 1), otherwise untouched.
 165 */
 166 /*  AF        - The analysis frame number */
 167 /* Output: */
 168 /*  VOIBUF(2,0:AF) - Buffer of voicing decisions */
 169 /*              Index (HALF,3) written. */
 170 /*              If (HALF .EQ. 1), skip down to "Read (HALF,3)" below. */
 171 /*              Indices (1,2), (2,1), (1,2), and (2,2) read. */
 172 /*              One of the following is then done: */
 173 /*                 read (1,3) and possibly write (1,2) */
 174 /*                 read (1,3) and write (1,2) or (2,2) */
 175 /*                 write (2,1) */
 176 /*                 write (2,1) or (1,2) */
 177 /*                 read (1,0) and (1,3) and then write (2,2) or (1,1) */
 178 /*                 no reads or writes on VOIBUF */
 179 /*              Finally, read (HALF,3) */
 180 /* Internal: */
 181 /*  QS        - Ratio of preemphasized to full-band energies */
 182 /*  RC1       - First reflection coefficient */
 183 /* AR_B      - Product of the causal forward and reverse pitch prediction gain
 184 s*/
 185 /* AR_F      - Product of the noncausal forward and rev. pitch prediction gain
 186 s*/
 187 /*  ZC        - Zero crossing rate */
 188 /*  DITHER    - Zero crossing threshold level */
 189 /*  MAXMIN    - AMDF's 1 octave windowed maximum-to-minimum ratio */
 190 /*  MINPTR    - Location  of minimum AMDF value */
 191 /*  NVDC      - Number of elements in each VDC vector */
 192 /*  NVDCL     - Number of VDC vectors */
 193 /*  VDCL      - SNR values corresponding to the set of VDC's */
 194 /*  VDC       - 2-D voicing decision coefficient vector */
 195 /*  VALUE(9)  - Voicing Parameters */
 196 /*  VOICE(2,3)- History of LDA results */
 197 /*              On every call when (HALF .EQ. 1), VOICE(*,I+1) is */
 198 /*              shifted back to VOICE(*,I), for I=1,2. */
 199 /*              VOICE(HALF,3) is written on every call. */
 200 /*              Depending on several conditions, one or more of */
 201 /*              (1,1), (1,2), (2,1), and (2,2) might then be read. */
 202 /*  LBE       - Ratio of low-band instantaneous to average energies */
 203 /*  FBE       - Ratio of full-band instantaneous to average energies */
 204 /*  LBVE      - Low band voiced energy */
 205 /*  LBUE      - Low band unvoiced energy */
 206 /*  FBVE      - Full band voiced energy */
 207 /*  FBUE      - Full band unvoiced energy */
 208 /*  OFBUE     - Previous full-band unvoiced energy */
 209 /*  OLBUE     - Previous low-band unvoiced energy */
 210 /*  REF       - Reference energy for initialization and DITHER threshold */
 211 /*  SNR       - Estimate of signal-to-noise ratio */
 212 /*  SNR2      - Estimate of low-band signal-to-noise ratio */
 213 /*  SNRL      - SNR level number */
 214 /*  OT        - Onset transition present */
 215 /*  VSTATE    - Decimal interpretation of binary voicing classifications */
 216 /*  FIRST     - First call flag */
 217
 218 /* This subroutine maintains local state from one call to the next.  If */
 219 /* you want to switch to using a new audio stream for this filter, or */
 220 /* reinitialize its state for any other reason, call the ENTRY */
 221 /* INITVOICIN. */
 222
 223 /* Subroutine */ int voicin_(integer *vwin, real *inbuf, real *
 224         lpbuf, integer *buflim, integer *half, real *minamd, real *maxamd,
 225         integer *mintau, real *ivrc, integer *obound, integer *voibuf,
 226         integer *af, struct lpc10_encoder_state *st)
 227 {
 228     /* Initialized data */
 229
 230     real *dither;
 231     static real vdc[100]        /* was [10][10] */ = { 0.f,1714.f,-110.f,
 232             334.f,-4096.f,-654.f,3752.f,3769.f,0.f,1181.f,0.f,874.f,-97.f,
 233             300.f,-4096.f,-1021.f,2451.f,2527.f,0.f,-500.f,0.f,510.f,-70.f,
 234             250.f,-4096.f,-1270.f,2194.f,2491.f,0.f,-1500.f,0.f,500.f,-10.f,
 235             200.f,-4096.f,-1300.f,2e3f,2e3f,0.f,-2e3f,0.f,500.f,0.f,0.f,
 236             -4096.f,-1300.f,2e3f,2e3f,0.f,-2500.f,0.f,0.f,0.f,0.f,0.f,0.f,0.f,
 237             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,
 238             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,
 239             0.f,0.f,0.f,0.f,0.f,0.f,0.f,0.f,0.f,0.f,0.f };
 240     static integer nvdcl = 5;
 241     static real vdcl[10] = { 600.f,450.f,300.f,200.f,0.f,0.f,0.f,0.f,0.f,0.f }
 242             ;
 243
 244     /* System generated locals */
 245     integer inbuf_offset = 0, lpbuf_offset = 0, i__1, i__2;
 246     real r__1, r__2;
 247
 248     /* Builtin functions */
 249     integer i_nint(real *);
 250     double sqrt(doublereal);
 251
 252     /* Local variables */
 253     real ar_b__, ar_f__;
 254     integer *lbve, *lbue, *fbve, *fbue;
 255     integer snrl, i__;
 256     integer *ofbue, *sfbue;
 257     real *voice;
 258     integer *olbue, *slbue;
 259     real value[9];
 260     integer zc;
 261     logical ot;
 262     real qs;
 263     real *maxmin;
 264     integer vstate;
 265     real rc1;
 266     extern /* Subroutine */ int vparms_(integer *, real *, real *, integer *,
 267             integer *, real *, integer *, integer *, integer *, integer *,
 268             real *, real *, real *, real *);
 269     integer fbe, lbe;
 270     real *snr;
 271     real snr2;
 272
 273     (void)af;
 274 /*      Global Variables: */
 275 /*       Arguments */
 276
 277 /*   LPC Processing control variables: */
 278
 279 /* *** Read-only: initialized in setup */
 280
 281 /*  Files for Speech, Parameter, and Bitstream Input & Output, */
 282 /*    and message and debug outputs. */
 283
 284 /* Here are the only files which use these variables: */
 285
 286 /* lpcsim.f setup.f trans.f error.f vqsetup.f */
 287
 288 /* Many files which use fdebug are not listed, since it is only used in */
 289 /* those other files conditionally, to print trace statements. */
 290 /*      integer fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
 291 /*  LPC order, Frame size, Quantization rate, Bits per frame, */
 292 /*    Error correction */
 293 /* Subroutine SETUP is the only place where order is assigned a value, */
 294 /* and that value is 10.  It could increase efficiency 1% or so to */
 295 /* declare order as a constant (i.e., a Fortran PARAMETER) instead of as
 296 */
 297 /* a variable in a COMMON block, since it is used in many places in the */
 298 /* core of the coding and decoding routines.  Actually, I take that back.
 299 */
 300 /* At least when compiling with f2c, the upper bound of DO loops is */
 301 /* stored in a local variable before the DO loop begins, and then that is
 302 */
 303 /* compared against on each iteration. */
 304 /* Similarly for lframe, which is given a value of MAXFRM in SETUP. */
 305 /* Similarly for quant, which is given a value of 2400 in SETUP.  quant */
 306 /* is used in only a few places, and never in the core coding and */
 307 /* decoding routines, so it could be eliminated entirely. */
 308 /* nbits is similar to quant, and is given a value of 54 in SETUP. */
 309 /* corrp is given a value of .TRUE. in SETUP, and is only used in the */
 310 /* subroutines ENCODE and DECODE.  It doesn't affect the speed of the */
 311 /* coder significantly whether it is .TRUE. or .FALSE., or whether it is
 312 */
 313 /* a constant or a variable, since it is only examined once per frame. */
 314 /* Leaving it as a variable that is set to .TRUE.  seems like a good */
 315 /* idea, since it does enable some error-correction capability for */
 316 /* unvoiced frames, with no change in the coding rate, and no noticeable
 317 */
 318 /* quality difference in the decoded speech. */
 319 /*      integer quant, nbits */
 320 /* *** Read/write: variables for debugging, not needed for LPC algorithm
 321 */
 322
 323 /*  Current frame, Unstable frames, Output clip count, Max onset buffer,
 324 */
 325 /*    Debug listing detail level, Line count on listing page */
 326
 327 /* nframe is not needed for an embedded LPC10 at all. */
 328 /* nunsfm is initialized to 0 in SETUP, and incremented in subroutine */
 329 /* ERROR, which is only called from RCCHK.  When LPC10 is embedded into */
 330 /* an application, I would recommend removing the call to ERROR in RCCHK,
 331 */
 332 /* and remove ERROR and nunsfm completely. */
 333 /* iclip is initialized to 0 in SETUP, and incremented in entry SWRITE in
 334 */
 335 /* sread.f.  When LPC10 is embedded into an application, one might want */
 336 /* to cause it to be incremented in a routine that takes the output of */
 337 /* SYNTHS and sends it to an audio device.  It could be optionally */
 338 /* displayed, for those that might want to know what it is. */
 339 /* maxosp is never initialized to 0 in SETUP, although it probably should
 340 */
 341 /* be, and it is updated in subroutine ANALYS.  I doubt that its value */
 342 /* would be of much interest to an application in which LPC10 is */
 343 /* embedded. */
 344 /* listl and lincnt are not needed for an embedded LPC10 at all. */
 345 /*      integer nframe, nunsfm, iclip, maxosp, listl, lincnt */
 346 /*      common /contrl/ fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
 347 /*      common /contrl/ quant, nbits */
 348 /*      common /contrl/ nframe, nunsfm, iclip, maxosp, listl, lincnt */
 349 /*      Parameters/constants */
 350 /*       Voicing coefficient and Linear Discriminant Analysis variables:
 351 */
 352 /*       Max number of VDC's and VDC levels */
 353 /*       The following are not Fortran PARAMETER's, but they are */
 354 /*       initialized with DATA statements, and never modified. */
 355 /*       Actual number of VDC's and levels */
 356 /*       Local variables that need not be saved */
 357 /*       Note: */
 358
 359 /*       VALUE(1) through VALUE(8) are assigned values, but VALUE(9) */
 360 /*       never is.  Yet VALUE(9) is read in the loop that begins "DO I =
 361 */
 362 /*       1, 9" below.  I believe that this doesn't cause any problems in
 363 */
 364 /*       this subroutine, because all VDC(9,*) array elements are 0, and
 365 */
 366 /*       this is what is multiplied by VALUE(9) in all cases.  Still, it
 367 */
 368 /*       would save a multiplication to change the loop to "DO I = 1, 8".
 369 */
 370 /*       Local state */
 371 /*       WARNING! */
 372
 373 /*       VOICE, SFBUE, and SLBUE should be saved from one invocation to */
 374 /*       the next, but they are never given an initial value. */
 375
 376 /*       Does Fortran 77 specify some default initial value, like 0, or */
 377 /*       is it undefined?  If it is undefined, then this code should be */
 378 /*       corrected to specify an initial value. */
 379
 380 /*       For VOICE, note that it is "shifted" in the statement that */
 381 /*       begins "IF (HALF .EQ. 1) THEN" below.  Also, uninitialized */
 382 /*       values in the VOICE array can only affect entries in the VOIBUF
 383 */
 384 /*       array that are for the same frame, or for an older frame.  Thus
 385 */
 386 /*       the effects of uninitialized values in VOICE cannot linger on */
 387 /*       for more than 2 or 3 frame times. */
 388
 389 /*       For SFBUE and SLBUE, the effects of uninitialized values can */
 390 /*       linger on for many frame times, because their previous values */
 391 /*       are exponentially decayed.  Thus it is more important to choose
 392 */
 393 /*       initial values for these variables.  I would guess that a */
 394 /*       reasonable initial value for SFBUE is REF/16, the same as used */
 395 /*       for FBUE and OFBUE.  Similarly, SLBUE can be initialized to */
 396 /*       REF/32, the same as for LBUE and OLBUE. */
 397
 398 /*       These guessed initial values should be validated by re-running */
 399 /*       the modified program on some audio samples. */
 400
 401 /*   Declare and initialize filters: */
 402
 403     dither = (&st->dither);
 404     snr = (&st->snr);
 405     maxmin = (&st->maxmin);
 406     voice = (&st->voice[0]);
 407     lbve = (&st->lbve);
 408     lbue = (&st->lbue);
 409     fbve = (&st->fbve);
 410     fbue = (&st->fbue);
 411     ofbue = (&st->ofbue);
 412     olbue = (&st->olbue);
 413     sfbue = (&st->sfbue);
 414     slbue = (&st->slbue);
 415
 416     /* Parameter adjustments */
 417     if (vwin) {
 418         --vwin;
 419         }
 420     if (buflim) {
 421         --buflim;
 422         }
 423     if (inbuf) {
 424         inbuf_offset = buflim[1];
 425         inbuf -= inbuf_offset;
 426         }
 427     if (lpbuf) {
 428         lpbuf_offset = buflim[3];
 429         lpbuf -= lpbuf_offset;
 430         }
 431     if (ivrc) {
 432         --ivrc;
 433         }
 434     if (obound) {
 435         --obound;
 436         }
 437     if (voibuf) {
 438         --voibuf;
 439         }
 440
 441     /* Function Body */
 442
 443 /*       The following variables are saved from one invocation to the */
 444 /*       next, but are not initialized with DATA statements.  This is */
 445 /*       acceptable, because FIRST is initialized ot .TRUE., and the */
 446 /*       first time that this subroutine is then called, they are all */
 447 /*       given initial values. */
 448
 449 /*       SNR */
 450 /*       LBVE, LBUE, FBVE, FBUE, OFBUE, OLBUE */
 451
 452 /*       MAXMIN is initialized on the first call, assuming that HALF */
 453 /*       .EQ. 1 on first call.  This is how ANALYS calls this subroutine.
 454 */
 455
 456 /*   Voicing Decision Parameter vector (* denotes zero coefficient): */
 457
 458 /*      * MAXMIN */
 459 /*        LBE/LBVE */
 460 /*        ZC */
 461 /*        RC1 */
 462 /*        QS */
 463 /*        IVRC2 */
 464 /*        aR_B */
 465 /*        aR_F */
 466 /*      * LOG(LBE/LBVE) */
 467 /*  Define 2-D voicing decision coefficient vector according to the voicin
 468 g*/
 469 /*  parameter order above.  Each row (VDC vector) is optimized for a speci
 470 fic*/
 471 /*   SNR.  The last element of the vector is the constant. */
 472 /*               E    ZC    RC1    Qs   IVRC2  aRb   aRf        c */
 473
 474 /*  The VOICE array contains the result of the linear discriminant functio
 475 n*/
 476 /*   (analog values).  The VOIBUF array contains the hard-limited binary
 477 */
 478 /*   voicing decisions.  The VOICE and VOIBUF arrays, according to FORTRAN
 479  */
 480 /*   memory allocation, are addressed as: */
 481
 482 /*         (half-frame number, future-frame number) */
 483
 484 /*         |   Past    |  Present  |  Future1  |  Future2  | */
 485 /*         | 1,0 | 2,0 | 1,1 | 2,1 | 1,2 | 2,2 | 1,3 | 2,3 |  --->  time */
 486
 487 /*   Update linear discriminant function history each frame: */
 488     if (*half == 1) {
 489         voice[0] = voice[2];
 490         voice[1] = voice[3];
 491         voice[2] = voice[4];
 492         voice[3] = voice[5];
 493         *maxmin = *maxamd / max(*minamd,1.f);
 494     }
 495 /*   Calculate voicing parameters twice per frame: */
 496     vparms_(&vwin[1], &inbuf[inbuf_offset], &lpbuf[lpbuf_offset], &buflim[1],
 497             half, dither, mintau, &zc, &lbe, &fbe, &qs, &rc1, &ar_b__, &
 498             ar_f__);
 499 /*   Estimate signal-to-noise ratio to select the appropriate VDC vector.
 500 */
 501 /*   The SNR is estimated as the running average of the ratio of the */
 502 /*   running average full-band voiced energy to the running average */
 503 /*   full-band unvoiced energy. SNR filter has gain of 63. */
 504     r__1 = (*snr + *fbve / (real) max(*fbue,1)) * 63 / 64.f;
 505     *snr = (real) i_nint(&r__1);
 506     snr2 = *snr * *fbue / max(*lbue,1);
 507 /*   Quantize SNR to SNRL according to VDCL thresholds. */
 508     snrl = 1;
 509     i__1 = nvdcl - 1;
 510     for (snrl = 1; snrl <= i__1; ++snrl) {
 511         if (snr2 > vdcl[snrl - 1]) {
 512             goto L69;
 513         }
 514     }
 515 /*      (Note:  SNRL = NVDCL here) */
 516 L69:
 517 /*   Linear discriminant voicing parameters: */
 518     value[0] = *maxmin;
 519     value[1] = (real) lbe / max(*lbve,1);
 520     value[2] = (real) zc;
 521     value[3] = rc1;
 522     value[4] = qs;
 523     value[5] = ivrc[2];
 524     value[6] = ar_b__;
 525     value[7] = ar_f__;
 526 /*   Evaluation of linear discriminant function: */
 527     voice[*half + 3] = vdc[snrl * 10 - 1];
 528     for (i__ = 1; i__ <= 8; ++i__) {
 529         voice[*half + 3] += vdc[i__ + snrl * 10 - 11] * value[i__ - 1];
 530     }
 531 /*   Classify as voiced if discriminant > 0, otherwise unvoiced */
 532 /*   Voicing decision for current half-frame:  1 = Voiced; 0 = Unvoiced */
 533     if (voice[*half + 3] > 0.f) {
 534         voibuf[*half + 6] = 1;
 535     } else {
 536         voibuf[*half + 6] = 0;
 537     }
 538 /*   Skip voicing decision smoothing in first half-frame: */
 539 /*     Give a value to VSTATE, so that trace statements below will print
 540 */
 541 /*     a consistent value from one call to the next when HALF .EQ. 1. */
 542 /*     The value of VSTATE is not used for any other purpose when this is
 543 */
 544 /*     true. */
 545     vstate = -1;
 546     if (*half == 1) {
 547         goto L99;
 548     }
 549 /*   Voicing decision smoothing rules (override of linear combination): */
 550
 551 /*      Unvoiced half-frames:  At least two in a row. */
 552 /*      -------------------- */
 553
 554 /*      Voiced half-frames:    At least two in a row in one frame. */
 555 /*      -------------------    Otherwise at least three in a row. */
 556 /*                             (Due to the way transition frames are encoded) */
 557
 558 /*      In many cases, the discriminant function determines how to smooth. */
 559 /*      In the following chart, the decisions marked with a * may be overridden
 560 .*/
 561
 562 /*   Voicing override of transitions at onsets: */
 563 /*      If a V/UV or UV/V voicing decision transition occurs within one-half
 564 */
 565 /*      frame of an onset bounding a voicing window, then the transition is */
 566 /*      moved to occur at the onset. */
 567
 568 /*      P       1F */
 569 /*      -----   ----- */
 570 /*      0   0   0   0 */
 571 /*      0   0   0*  1   (If there is an onset there) */
 572 /*      0   0   1*  0*  (Based on 2F and discriminant distance) */
 573 /*      0   0   1   1 */
 574 /*      0   1*  0   0   (Always) */
 575 /*      0   1*  0*  1   (Based on discriminant distance) */
 576 /*      0*  1   1   0*  (Based on past, 2F, and discriminant distance) */
 577 /*      0   1*  1   1   (If there is an onset there) */
 578 /*      1   0*  0   0   (If there is an onset there) */
 579 /*      1   0   0   1 */
 580 /*      1   0*  1*  0   (Based on discriminant distance) */
 581 /*      1   0*  1   1   (Always) */
 582 /*      1   1   0   0 */
 583 /*      1   1   0*  1*  (Based on 2F and discriminant distance) */
 584 /*      1   1   1*  0   (If there is an onset there) */
 585 /*      1   1   1   1 */
 586
 587 /*   Determine if there is an onset transition between P and 1F. */
 588 /*   OT (Onset Transition) is true if there is an onset between */
 589 /*   P and 1F but not after 1F. */
 590     ot = ((obound[1] & 2) != 0 || obound[2] == 1) && (obound[3] & 1) == 0;
 591 /*   Multi-way dispatch on voicing decision history: */
 592     vstate = (voibuf[3] << 3) + (voibuf[4] << 2) + (voibuf[5] << 1) + voibuf[
 593             6];
 594     switch (vstate + 1) {
 595         case 1:  goto L99;
 596         case 2:  goto L1;
 597         case 3:  goto L2;
 598         case 4:  goto L99;
 599         case 5:  goto L4;
 600         case 6:  goto L5;
 601         case 7:  goto L6;
 602         case 8:  goto L7;
 603         case 9:  goto L8;
 604         case 10:  goto L99;
 605         case 11:  goto L10;
 606         case 12:  goto L11;
 607         case 13:  goto L99;
 608         case 14:  goto L13;
 609         case 15:  goto L14;
 610         case 16:  goto L99;
 611     }
 612 L1:
 613     if (ot && voibuf[7] == 1) {
 614         voibuf[5] = 1;
 615     }
 616     goto L99;
 617 L2:
 618     if (voibuf[7] == 0 || voice[2] < -voice[3]) {
 619         voibuf[5] = 0;
 620     } else {
 621         voibuf[6] = 1;
 622     }
 623     goto L99;
 624 L4:
 625     voibuf[4] = 0;
 626     goto L99;
 627 L5:
 628     if (voice[1] < -voice[2]) {
 629         voibuf[4] = 0;
 630     } else {
 631         voibuf[5] = 1;
 632     }
 633     goto L99;
 634 /*   VOIBUF(2,0) must be 0 */
 635 L6:
 636     if (voibuf[1] == 1 || voibuf[7] == 1 || voice[3] > voice[0]) {
 637         voibuf[6] = 1;
 638     } else {
 639         voibuf[3] = 1;
 640     }
 641     goto L99;
 642 L7:
 643     if (ot) {
 644         voibuf[4] = 0;
 645     }
 646     goto L99;
 647 L8:
 648     if (ot) {
 649         voibuf[4] = 1;
 650     }
 651     goto L99;
 652 L10:
 653     if (voice[2] < -voice[1]) {
 654         voibuf[5] = 0;
 655     } else {
 656         voibuf[4] = 1;
 657     }
 658     goto L99;
 659 L11:
 660     voibuf[4] = 1;
 661     goto L99;
 662 L13:
 663     if (voibuf[7] == 0 && voice[3] < -voice[2]) {
 664         voibuf[6] = 0;
 665     } else {
 666         voibuf[5] = 1;
 667     }
 668     goto L99;
 669 L14:
 670     if (ot && voibuf[7] == 0) {
 671         voibuf[5] = 0;
 672     }
 673 /*      GOTO 99 */
 674 L99:
 675 /*   Now update parameters: */
 676 /*   ---------------------- */
 677
 678 /*  During unvoiced half-frames, update the low band and full band unvoice
 679 d*/
 680 /*   energy estimates (LBUE and FBUE) and also the zero crossing */
 681 /*   threshold (DITHER).  (The input to the unvoiced energy filters is */
 682 /*   restricted to be less than 10dB above the previous inputs of the */
 683 /*   filters.) */
 684 /*   During voiced half-frames, update the low-pass (LBVE) and all-pass */
 685 /*   (FBVE) voiced energy estimates. */
 686     if (voibuf[*half + 6] == 0) {
 687 /* Computing MIN */
 688         i__1 = fbe, i__2 = *ofbue * 3;
 689         r__1 = (*sfbue * 63 + (min(i__1,i__2) << 3)) / 64.f;
 690         *sfbue = i_nint(&r__1);
 691         *fbue = *sfbue / 8;
 692         *ofbue = fbe;
 693 /* Computing MIN */
 694         i__1 = lbe, i__2 = *olbue * 3;
 695         r__1 = (*slbue * 63 + (min(i__1,i__2) << 3)) / 64.f;
 696         *slbue = i_nint(&r__1);
 697         *lbue = *slbue / 8;
 698         *olbue = lbe;
 699     } else {
 700         r__1 = (*lbve * 63 + lbe) / 64.f;
 701         *lbve = i_nint(&r__1);
 702         r__1 = (*fbve * 63 + fbe) / 64.f;
 703         *fbve = i_nint(&r__1);
 704     }
 705 /*   Set dither threshold to yield proper zero crossing rates in the */
 706 /*   presence of low frequency noise and low level signal input. */
 707 /*   NOTE: The divisor is a function of REF, the expected energies. */
 708 /* Computing MIN */
 709 /* Computing MAX */
 710     r__2 = sqrt((real) (*lbue * *lbve)) * 64 / 3000;
 711     r__1 = max(r__2,1.f);
 712     *dither = min(r__1,20.f);
 713 /*   Voicing decisions are returned in VOIBUF. */
 714     return 0;
 715 } /* voicin_ */