Asterisk - The Open Source Telephony Project  18.5.0
dyptrk.c
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1 /*
2 
3 $Log$
4 Revision 1.15 2004/06/26 03:50:14 markster
5 Merge source cleanups (bug #1911)
6 
7 Revision 1.14 2003/02/12 13:59:15 matteo
8 mer feb 12 14:56:57 CET 2003
9 
10 Revision 1.1.1.1 2003/02/12 13:59:15 matteo
11 mer feb 12 14:56:57 CET 2003
12 
13 Revision 1.2 2000/01/05 08:20:39 markster
14 Some OSS fixes and a few lpc changes to make it actually work
15 
16  * Revision 1.2 1996/08/20 20:25:29 jaf
17  * Removed all static local variables that were SAVE'd in the Fortran
18  * code, and put them in struct lpc10_encoder_state that is passed as an
19  * argument.
20  *
21  * Removed init function, since all initialization is now done in
22  * init_lpc10_encoder_state().
23  *
24  * Revision 1.1 1996/08/19 22:32:26 jaf
25  * Initial revision
26  *
27 
28 */
29 
30 /* -- translated by f2c (version 19951025).
31  You must link the resulting object file with the libraries:
32  -lf2c -lm (in that order)
33 */
34 
35 #include "f2c.h"
36 
37 #ifdef P_R_O_T_O_T_Y_P_E_S
38 extern int dyptrk_(real *amdf, integer *ltau, integer *minptr, integer *voice, integer *pitch, integer *midx, struct lpc10_encoder_state *st);
39 /* comlen contrl_ 12 */
40 #endif
41 
42 /* Common Block Declarations */
43 
44 extern struct {
47 } contrl_;
48 
49 #define contrl_1 contrl_
50 
51 /* ********************************************************************* */
52 
53 /* DYPTRK Version 52 */
54 
55 /* $Log$
56  * Revision 1.15 2004/06/26 03:50:14 markster
57  * Merge source cleanups (bug #1911)
58  *
59  * Revision 1.14 2003/02/12 13:59:15 matteo
60  * mer feb 12 14:56:57 CET 2003
61  *
62  * Revision 1.1.1.1 2003/02/12 13:59:15 matteo
63  * mer feb 12 14:56:57 CET 2003
64  *
65  * Revision 1.2 2000/01/05 08:20:39 markster
66  * Some OSS fixes and a few lpc changes to make it actually work
67  *
68  * Revision 1.2 1996/08/20 20:25:29 jaf
69  * Removed all static local variables that were SAVE'd in the Fortran
70  * code, and put them in struct lpc10_encoder_state that is passed as an
71  * argument.
72  *
73  * Removed init function, since all initialization is now done in
74  * init_lpc10_encoder_state().
75  *
76  * Revision 1.1 1996/08/19 22:32:26 jaf
77  * Initial revision
78  * */
79 /* Revision 1.5 1996/03/26 19:35:35 jaf */
80 /* Commented out trace statements. */
81 
82 /* Revision 1.4 1996/03/19 18:03:22 jaf */
83 /* Replaced the initialization "DATA P/60*DEPTH*0/" with "DATA P/120*0/", */
84 /* because apparently Fortran (or at least f2c) can't handle expressions */
85 /* like that. */
86 
87 /* Revision 1.3 1996/03/19 17:38:32 jaf */
88 /* Added comments about the local variables that should be saved from one */
89 /* invocation to the next. None of them were given initial values in the */
90 /* original code, but from my testing, it appears that initializing them */
91 /* all to 0 works. */
92 
93 /* Added entry INITDYPTRK to reinitialize these local variables. */
94 
95 /* Revision 1.2 1996/03/13 16:32:17 jaf */
96 /* Comments added explaining which of the local variables of this */
97 /* subroutine need to be saved from one invocation to the next, and which */
98 /* do not. */
99 
100 /* WARNING! Some of them that should are never given initial values in */
101 /* this code. Hopefully, Fortran 77 defines initial values for them, but */
102 /* even so, giving them explicit initial values is preferable. */
103 
104 /* Revision 1.1 1996/02/07 14:45:14 jaf */
105 /* Initial revision */
106 
107 
108 /* ********************************************************************* */
109 
110 /* Dynamic Pitch Tracker */
111 
112 /* Input: */
113 /* AMDF - Average Magnitude Difference Function array */
114 /* Indices 1 through LTAU read, and MINPTR */
115 /* LTAU - Number of lags in AMDF */
116 /* MINPTR - Location of minimum AMDF value */
117 /* VOICE - Voicing decision */
118 /* Output: */
119 /* PITCH - Smoothed pitch value, 2 frames delayed */
120 /* MIDX - Initial estimate of current frame pitch */
121 /* Compile time constant: */
122 /* DEPTH - Number of frames to trace back */
123 
124 /* This subroutine maintains local state from one call to the next. If */
125 /* you want to switch to using a new audio stream for this filter, or */
126 /* reinitialize its state for any other reason, call the ENTRY */
127 /* INITDYPTRK. */
128 
129 /* Subroutine */ int dyptrk_(real *amdf, integer *ltau, integer *
130  minptr, integer *voice, integer *pitch, integer *midx,
131  struct lpc10_encoder_state *st)
132 {
133  /* Initialized data */
134 
135  real *s;
136  integer *p;
137  integer *ipoint;
138  real *alphax;
139 
140  /* System generated locals */
141  integer i__1;
142 
143  /* Local variables */
144  integer pbar;
145  real sbar;
146  integer iptr, i__, j;
147  real alpha, minsc, maxsc;
148 
149 /* Arguments */
150 /* $Log$
151  * Revision 1.15 2004/06/26 03:50:14 markster
152  * Merge source cleanups (bug #1911)
153  *
154  * Revision 1.14 2003/02/12 13:59:15 matteo
155  * mer feb 12 14:56:57 CET 2003
156  *
157  * Revision 1.1.1.1 2003/02/12 13:59:15 matteo
158  * mer feb 12 14:56:57 CET 2003
159  *
160  * Revision 1.2 2000/01/05 08:20:39 markster
161  * Some OSS fixes and a few lpc changes to make it actually work
162  *
163  * Revision 1.2 1996/08/20 20:25:29 jaf
164  * Removed all static local variables that were SAVE'd in the Fortran
165  * code, and put them in struct lpc10_encoder_state that is passed as an
166  * argument.
167  *
168  * Removed init function, since all initialization is now done in
169  * init_lpc10_encoder_state().
170  *
171  * Revision 1.1 1996/08/19 22:32:26 jaf
172  * Initial revision
173  * */
174 /* Revision 1.3 1996/03/29 22:05:55 jaf */
175 /* Commented out the common block variables that are not needed by the */
176 /* embedded version. */
177 
178 /* Revision 1.2 1996/03/26 19:34:50 jaf */
179 /* Added comments indicating which constants are not needed in an */
180 /* application that uses the LPC-10 coder. */
181 
182 /* Revision 1.1 1996/02/07 14:44:09 jaf */
183 /* Initial revision */
184 
185 /* LPC Processing control variables: */
186 
187 /* *** Read-only: initialized in setup */
188 
189 /* Files for Speech, Parameter, and Bitstream Input & Output, */
190 /* and message and debug outputs. */
191 
192 /* Here are the only files which use these variables: */
193 
194 /* lpcsim.f setup.f trans.f error.f vqsetup.f */
195 
196 /* Many files which use fdebug are not listed, since it is only used in */
197 /* those other files conditionally, to print trace statements. */
198 /* integer fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
199 /* LPC order, Frame size, Quantization rate, Bits per frame, */
200 /* Error correction */
201 /* Subroutine SETUP is the only place where order is assigned a value, */
202 /* and that value is 10. It could increase efficiency 1% or so to */
203 /* declare order as a constant (i.e., a Fortran PARAMETER) instead of as
204 */
205 /* a variable in a COMMON block, since it is used in many places in the */
206 /* core of the coding and decoding routines. Actually, I take that back.
207 */
208 /* At least when compiling with f2c, the upper bound of DO loops is */
209 /* stored in a local variable before the DO loop begins, and then that is
210 */
211 /* compared against on each iteration. */
212 /* Similarly for lframe, which is given a value of MAXFRM in SETUP. */
213 /* Similarly for quant, which is given a value of 2400 in SETUP. quant */
214 /* is used in only a few places, and never in the core coding and */
215 /* decoding routines, so it could be eliminated entirely. */
216 /* nbits is similar to quant, and is given a value of 54 in SETUP. */
217 /* corrp is given a value of .TRUE. in SETUP, and is only used in the */
218 /* subroutines ENCODE and DECODE. It doesn't affect the speed of the */
219 /* coder significantly whether it is .TRUE. or .FALSE., or whether it is
220 */
221 /* a constant or a variable, since it is only examined once per frame. */
222 /* Leaving it as a variable that is set to .TRUE. seems like a good */
223 /* idea, since it does enable some error-correction capability for */
224 /* unvoiced frames, with no change in the coding rate, and no noticeable
225 */
226 /* quality difference in the decoded speech. */
227 /* integer quant, nbits */
228 /* *** Read/write: variables for debugging, not needed for LPC algorithm
229 */
230 
231 /* Current frame, Unstable frames, Output clip count, Max onset buffer,
232 */
233 /* Debug listing detail level, Line count on listing page */
234 
235 /* nframe is not needed for an embedded LPC10 at all. */
236 /* nunsfm is initialized to 0 in SETUP, and incremented in subroutine */
237 /* ERROR, which is only called from RCCHK. When LPC10 is embedded into */
238 /* an application, I would recommend removing the call to ERROR in RCCHK,
239 */
240 /* and remove ERROR and nunsfm completely. */
241 /* iclip is initialized to 0 in SETUP, and incremented in entry SWRITE in
242 */
243 /* sread.f. When LPC10 is embedded into an application, one might want */
244 /* to cause it to be incremented in a routine that takes the output of */
245 /* SYNTHS and sends it to an audio device. It could be optionally */
246 /* displayed, for those that might want to know what it is. */
247 /* maxosp is never initialized to 0 in SETUP, although it probably should
248 */
249 /* be, and it is updated in subroutine ANALYS. I doubt that its value */
250 /* would be of much interest to an application in which LPC10 is */
251 /* embedded. */
252 /* listl and lincnt are not needed for an embedded LPC10 at all. */
253 /* integer nframe, nunsfm, iclip, maxosp, listl, lincnt */
254 /* common /contrl/ fsi, fso, fpi, fpo, fbi, fbo, pbin, fmsg, fdebug */
255 /* common /contrl/ quant, nbits */
256 /* common /contrl/ nframe, nunsfm, iclip, maxosp, listl, lincnt */
257 /* Parameters/constants */
258 /* Local variables that need not be saved */
259 /* Note that PATH is only used for debugging purposes, and can be */
260 /* removed. */
261 /* Local state */
262 /* It would be a bit more "general" to define S(LTAU), if Fortran */
263 /* allows the argument of a function to be used as the dimension of
264 */
265 /* a local array variable. */
266 /* IPOINT is always in the range 0 to DEPTH-1. */
267 /* WARNING! */
268 
269 /* In the original version of this subroutine, IPOINT, ALPHAX, */
270 /* every element of S, and potentially any element of P with the */
271 /* second index value .NE. IPTR were read without being given */
272 /* initial values (all indices of P with second index equal to */
273 /* IPTR are all written before being read in this subroutine). */
274 
275 /* From examining the code carefully, it appears that all of these
276 */
277 /* should be saved from one invocation to the next. */
278 
279 /* I've run lpcsim with the "-l 6" option to see all of the */
280 /* debugging information that is printed out by this subroutine */
281 /* below, and it appears that S, P, IPOINT, and ALPHAX are all */
282 /* initialized to 0 (these initial values would likely be different
283 */
284 /* on different platforms, compilers, etc.). Given that the output
285 */
286 /* of the coder sounds reasonable, I'm going to initialize these */
287 /* variables to 0 explicitly. */
288 
289  s = &(st->s[0]);
290  p = &(st->p[0]);
291  ipoint = &(st->ipoint);
292  alphax = &(st->alphax);
293 
294 
295  /* Parameter adjustments */
296  if (amdf) {
297  --amdf;
298  }
299 
300  /* Function Body */
301 
302 /* Calculate the confidence factor ALPHA, used as a threshold slope in
303 */
304 /* SEESAW. If unvoiced, set high slope so that every point in P array
305 */
306 /* is marked as a potential pitch frequency. A scaled up version (ALPHAX
307 )*/
308 /* is used to maintain arithmetic precision. */
309  if (*voice == 1) {
310  *alphax = *alphax * .75f + amdf[*minptr] / 2.f;
311  } else {
312  *alphax *= .984375f;
313  }
314  alpha = *alphax / 16;
315  if (*voice == 0 && *alphax < 128.f) {
316  alpha = 8.f;
317  }
318 /* SEESAW: Construct a pitch pointer array and intermediate winner functio
319 n*/
320 /* Left to right pass: */
321  iptr = *ipoint + 1;
322  p[iptr * 60 - 60] = 1;
323  i__ = 1;
324  pbar = 1;
325  sbar = s[0];
326  i__1 = *ltau;
327  for (i__ = 1; i__ <= i__1; ++i__) {
328  sbar += alpha;
329  if (sbar < s[i__ - 1]) {
330  s[i__ - 1] = sbar;
331  p[i__ + iptr * 60 - 61] = pbar;
332  } else {
333  sbar = s[i__ - 1];
334  p[i__ + iptr * 60 - 61] = i__;
335  pbar = i__;
336  }
337  }
338 /* Right to left pass: */
339  i__ = pbar - 1;
340  sbar = s[i__];
341  while(i__ >= 1) {
342  sbar += alpha;
343  if (sbar < s[i__ - 1]) {
344  s[i__ - 1] = sbar;
345  p[i__ + iptr * 60 - 61] = pbar;
346  } else {
347  pbar = p[i__ + iptr * 60 - 61];
348  i__ = pbar;
349  sbar = s[i__ - 1];
350  }
351  --i__;
352  }
353 /* Update S using AMDF */
354 /* Find maximum, minimum, and location of minimum */
355  s[0] += amdf[1] / 2;
356  minsc = s[0];
357  maxsc = minsc;
358  *midx = 1;
359  i__1 = *ltau;
360  for (i__ = 2; i__ <= i__1; ++i__) {
361  s[i__ - 1] += amdf[i__] / 2;
362  if (s[i__ - 1] > maxsc) {
363  maxsc = s[i__ - 1];
364  }
365  if (s[i__ - 1] < minsc) {
366  *midx = i__;
367  minsc = s[i__ - 1];
368  }
369  }
370 /* Subtract MINSC from S to prevent overflow */
371  i__1 = *ltau;
372  for (i__ = 1; i__ <= i__1; ++i__) {
373  s[i__ - 1] -= minsc;
374  }
375  maxsc -= minsc;
376 /* Use higher octave pitch if significant null there */
377  j = 0;
378  for (i__ = 20; i__ <= 40; i__ += 10) {
379  if (*midx > i__) {
380  if (s[*midx - i__ - 1] < maxsc / 4) {
381  j = i__;
382  }
383  }
384  }
385  *midx -= j;
386 /* TRACE: look back two frames to find minimum cost pitch estimate */
387  j = *ipoint;
388  *pitch = *midx;
389  for (i__ = 1; i__ <= 2; ++i__) {
390  j = j % 2 + 1;
391  *pitch = p[*pitch + j * 60 - 61];
392  }
393 
394 /* The following statement subtracts one from IPOINT, mod DEPTH. I
395 */
396 /* think the author chose to add DEPTH-1, instead of subtracting 1,
397 */
398 /* because then it will work even if MOD doesn't work as desired on
399 */
400 /* negative arguments. */
401 
402  *ipoint = (*ipoint + 1) % 2;
403  return 0;
404 } /* dyptrk_ */
logical corrp
Definition: dyptrk.c:46
struct @190 contrl_
integer p[120]
Definition: lpc10.h:139
float real
Definition: lpc10.h:79
int dyptrk_(real *amdf, integer *ltau, integer *minptr, integer *voice, integer *pitch, integer *midx, struct lpc10_encoder_state *st)
Definition: dyptrk.c:129
integer order
Definition: dyptrk.c:45
real s[60]
Definition: lpc10.h:138
INT32 logical
Definition: lpc10.h:81
integer ipoint
Definition: lpc10.h:140
INT32 integer
Definition: lpc10.h:80
integer lframe
Definition: dyptrk.c:45