1 /*
2
3 * Revision 1.1 1996/08/19 22:32:31 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 difmag_(real *speech, integer *lpita, integer *tau, integer *ltau, integer *maxlag, real *amdf, integer *minptr, integer *maxptr);
17
18 /* ********************************************************************** */
19
20 /* DIFMAG Version 49 */
21
22 /*
23 * Revision 1.1 1996/08/19 22:32:31 jaf
24 * Initial revision
25 * */
26 /* Revision 1.3 1996/03/15 23:09:39 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 14:41:31 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 14:45:04 jaf */
35 /* Initial revision */
36
37
38 /* ********************************************************************* */
39
40 /* Compute Average Magnitude Difference Function */
41
42 /* Inputs: */
43 /* SPEECH - Low pass filtered speech */
44 /* Indices MIN_N1 through MAX_N1+LPITA-1 are read, where */
45 /* MIN_N1 = (MAXLAG - MAX_TAU)/2+1 MAX_TAU = max of TAU(I) for I=1,LTAU
46 */
47 /* MAX_N1 = (MAXLAG - MIN_TAU)/2+1 MIN_TAU = min of TAU(I) for I=1,LTAU
48 */
49 /* LPITA - Length of speech buffer */
50 /* TAU - Table of lags */
51 /* Indices 1 through LTAU read. */
52 /* LTAU - Number of lag values to compute */
53 /* MAXLAG - Maximum possible lag value */
54 /* Outputs: */
55 /* (All of these outputs are also read, but only after being written.) */
56 /* AMDF - Average Magnitude Difference for each lag in TAU */
57 /* Indices 1 through LTAU written */
58 /* MINPTR - Index of minimum AMDF value */
59 /* MAXPTR - Index of maximum AMDF value */
60
61 /* This subroutine has no local state. */
62
difmag_(real * speech,integer * lpita,integer * tau,integer * ltau,integer * maxlag,real * amdf,integer * minptr,integer * maxptr)63 /* Subroutine */ int difmag_(real *speech, integer *lpita, integer *tau,
64 integer *ltau, integer *maxlag, real *amdf, integer *minptr, integer *
65 maxptr)
66 {
67 /* System generated locals */
68 integer i__1, i__2;
69 real r__1;
70
71 /* Local variables */
72 integer i__, j, n1, n2;
73 real sum;
74
75 /* Arguments */
76 /* Local variables that need not be saved */
77 /* Local state */
78 /* None */
79 /* Parameter adjustments */
80 --amdf;
81 --tau;
82 --speech;
83
84 /* Function Body */
85 *minptr = 1;
86 *maxptr = 1;
87 i__1 = *ltau;
88 for (i__ = 1; i__ <= i__1; ++i__) {
89 n1 = (*maxlag - tau[i__]) / 2 + 1;
90 n2 = n1 + *lpita - 1;
91 sum = 0.f;
92 i__2 = n2;
93 for (j = n1; j <= i__2; j += 4) {
94 sum += (r__1 = speech[j] - speech[j + tau[i__]], abs(r__1));
95 }
96 amdf[i__] = sum;
97 if (amdf[i__] < amdf[*minptr]) {
98 *minptr = i__;
99 }
100 if (amdf[i__] > amdf[*maxptr]) {
101 *maxptr = i__;
102 }
103 }
104 return 0;
105 } /* difmag_ */
106
107