1 /*
2
3 * Revision 1.1 1996/08/19 22:30:26 jaf
4 * Initial revision
5 *
6
7 */
8
9 /* -- translated by f2c (version 19951025).
10 You must link the resulting object file with the libraries:
11 -lf2c -lm (in that order)
12 */
13
14 #include "f2c.h"
15
16 extern int tbdm_(real *speech, integer *lpita, integer *tau, integer *ltau, real *amdf, integer *minptr, integer *maxptr, integer *mintau);
17
18 /* ********************************************************************** */
19
20 /* TBDM Version 49 */
21
22 /*
23 * Revision 1.1 1996/08/19 22:30:26 jaf
24 * Initial revision
25 * */
26 /* Revision 1.3 1996/03/18 22:14:00 jaf */
27 /* Just added a few comments about which array indices of the arguments */
28 /* are used, and mentioning that this subroutine has no local state. */
29
30 /* Revision 1.2 1996/03/13 14:48:37 jaf */
31 /* Comments added explaining that none of the local variables of this */
32 /* subroutine need to be saved from one invocation to the next. */
33
34 /* Revision 1.1 1996/02/07 14:49:54 jaf */
35 /* Initial revision */
36
37
38 /* ********************************************************************* */
39
40 /*TURBO DIFMAG: Compute High Resolution Average Magnitude Difference Function
41 */
42
43 /* Note: There are several constants in here that appear to depend on a */
44 /* particular TAU table. That's not a problem for the LPC10 coder, but */
45 /* watch out if you change the contents of TAU in the subroutine ANALYS. */
46
47 /* Input: */
48 /* SPEECH - Low pass filtered speech */
49 /* Indices 1 through MAX+LPITA-1 are read, where: */
50 /* MAX = (TAU(LTAU)-TAU(1))/2+1 */
51 /* (If TAU(1) .LT. 39, then larger indices could be read */
52 /* by the last call to DIFMAG below.) */
53 /* LPITA - Length of speech buffer */
54 /* TAU - Table of lags, sorted in increasing order. */
55 /* Indices 1 through LTAU read. */
56 /* LTAU - Number of lag values to compute */
57 /* Output: */
58 /* AMDF - Average Magnitude Difference for each lag in TAU */
59 /* Indices 1 through LTAU written, and several might then be read.*/
60 /* MINPTR - Index of minimum AMDF value */
61 /* MAXPTR - Index of maximum AMDF value within +/- 1/2 octave of min */
62 /* MINTAU - Lag corresponding to minimum AMDF value */
63
64 /* This subroutine has no local state. */
65
tbdm_(real * speech,integer * lpita,integer * tau,integer * ltau,real * amdf,integer * minptr,integer * maxptr,integer * mintau)66 /* Subroutine */ int tbdm_(real *speech, integer *lpita, integer *tau,
67 integer *ltau, real *amdf, integer *minptr, integer *maxptr, integer *
68 mintau)
69 {
70 /* System generated locals */
71 integer i__1, i__2, i__3, i__4;
72
73 /* Local variables */
74 real amdf2[6];
75 integer minp2, ltau2, maxp2, i__;
76 extern /* Subroutine */ int difmag_(real *, integer *, integer *, integer
77 *, integer *, real *, integer *, integer *);
78 integer minamd, ptr, tau2[6];
79
80 /* Arguments */
81 /* REAL SPEECH(LPITA+TAU(LTAU)), AMDF(LTAU) */
82 /* Stupid TOAST doesn't understand expressions */
83 /* Local variables that need not be saved */
84 /* Local state */
85 /* None */
86 /* Compute full AMDF using log spaced lags, find coarse minimum */
87 /* Parameter adjustments */
88 --speech;
89 --amdf;
90 --tau;
91
92 /* Function Body */
93 difmag_(&speech[1], lpita, &tau[1], ltau, &tau[*ltau], &amdf[1], minptr,
94 maxptr);
95 *mintau = tau[*minptr];
96 minamd = amdf[*minptr];
97 /* Build table containing all lags within +/- 3 of the AMDF minimum */
98 /* excluding all that have already been computed */
99 ltau2 = 0;
100 ptr = *minptr - 2;
101 /* Computing MAX */
102 i__1 = *mintau - 3;
103 /* Computing MIN */
104 i__3 = *mintau + 3, i__4 = tau[*ltau] - 1;
105 i__2 = min(i__3,i__4);
106 for (i__ = max(i__1,41); i__ <= i__2; ++i__) {
107 while(tau[ptr] < i__) {
108 ++ptr;
109 }
110 if (tau[ptr] != i__) {
111 ++ltau2;
112 tau2[ltau2 - 1] = i__;
113 }
114 }
115 /* Compute AMDF of the new lags, if there are any, and choose one */
116 /* if it is better than the coarse minimum */
117 if (ltau2 > 0) {
118 difmag_(&speech[1], lpita, tau2, <au2, &tau[*ltau], amdf2, &minp2, &
119 maxp2);
120 if (amdf2[minp2 - 1] < (real) minamd) {
121 *mintau = tau2[minp2 - 1];
122 minamd = amdf2[minp2 - 1];
123 }
124 }
125 /* Check one octave up, if there are any lags not yet computed */
126 if (*mintau >= 80) {
127 i__ = *mintau / 2;
128 if ((i__ & 1) == 0) {
129 ltau2 = 2;
130 tau2[0] = i__ - 1;
131 tau2[1] = i__ + 1;
132 } else {
133 ltau2 = 1;
134 tau2[0] = i__;
135 }
136 difmag_(&speech[1], lpita, tau2, <au2, &tau[*ltau], amdf2, &minp2, &
137 maxp2);
138 if (amdf2[minp2 - 1] < (real) minamd) {
139 *mintau = tau2[minp2 - 1];
140 minamd = amdf2[minp2 - 1];
141 *minptr += -20;
142 }
143 }
144 /* Force minimum of the AMDF array to the high resolution minimum */
145 amdf[*minptr] = (real) minamd;
146 /* Find maximum of AMDF within 1/2 octave of minimum */
147 /* Computing MAX */
148 i__2 = *minptr - 5;
149 *maxptr = max(i__2,1);
150 /* Computing MIN */
151 i__1 = *minptr + 5;
152 i__2 = min(i__1,*ltau);
153 for (i__ = *maxptr + 1; i__ <= i__2; ++i__) {
154 if (amdf[i__] > amdf[*maxptr]) {
155 *maxptr = i__;
156 }
157 }
158 return 0;
159 } /* tbdm_ */
160
161