1 /*
2
3 * Revision 1.2 1996/08/20 20:20:24 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 * Revision 1.1 1996/08/19 22:40:31 jaf
9 * Initial revision
10 *
11
12 */
13
14 /* -- translated by f2c (version 19951025).
15 You must link the resulting object file with the libraries:
16 -lf2c -lm (in that order)
17 */
18
19 #include "f2c.h"
20
21 int chanwr_(integer *order, integer *ipitv, integer *irms, integer *irc, integer *ibits, struct lpc10_encoder_state *st);
22 int chanrd_(integer *order, integer *ipitv, integer *irms, integer *irc, integer *ibits);
23
24 /* *********************************************************************** */
25
26 /* CHANL Version 49 */
27
28 /*
29 * Revision 1.2 1996/08/20 20:20:24 jaf
30 * Removed all static local variables that were SAVE'd in the Fortran
31 * code, and put them in struct lpc10_encoder_state that is passed as an
32 * argument.
33 *
34 * Revision 1.1 1996/08/19 22:40:31 jaf
35 * Initial revision
36 * */
37 /* Revision 1.3 1996/03/21 15:14:57 jaf */
38 /* Added comments about which indices of argument arrays are read or */
39 /* written, and about the one bit of local state in CHANWR. CHANRD */
40 /* has no local state. */
41
42 /* Revision 1.2 1996/03/13 18:55:10 jaf */
43 /* Comments added explaining which of the local variables of this */
44 /* subroutine need to be saved from one invocation to the next, and which */
45 /* do not. */
46
47 /* Revision 1.1 1996/02/07 14:43:31 jaf */
48 /* Initial revision */
49
50
51 /* *********************************************************************** */
52
53 /* CHANWR: */
54 /* Place quantized parameters into bitstream */
55
56 /* Input: */
57 /* ORDER - Number of reflection coefficients (not really variable) */
58 /* IPITV - Quantized pitch/voicing parameter */
59 /* IRMS - Quantized energy parameter */
60 /* IRC - Quantized reflection coefficients */
61 /* Indices 1 through ORDER read. */
62 /* Output: */
63 /* IBITS - Serial bitstream */
64 /* Indices 1 through 54 written. */
65 /* Bit 54, the SYNC bit, alternates from one call to the next. */
66
67 /* Subroutine CHANWR maintains one bit of local state from one call to */
68 /* the next, in the variable ISYNC. I believe that this one bit is only */
69 /* intended to allow a receiver to resynchronize its interpretation of */
70 /* the bit stream, by looking for which of the 54 bits alternates every */
71 /* frame time. This is just a simple framing mechanism that is not */
72 /* useful when other, higher overhead framing mechanisms are used to */
73 /* transmit the coded frames. */
74
75 /* I'm not going to make an entry to reinitialize this bit, since it */
76 /* doesn't help a receiver much to know whether the first sync bit is a 0 */
77 /* or a 1. It needs to examine several frames in sequence to have */
78 /* reasonably good assurance that its framing is correct. */
79
80
81 /* CHANRD: */
82 /* Reconstruct parameters from bitstream */
83
84 /* Input: */
85 /* ORDER - Number of reflection coefficients (not really variable) */
86 /* IBITS - Serial bitstream */
87 /* Indices 1 through 53 read (SYNC bit is ignored). */
88 /* Output: */
89 /* IPITV - Quantized pitch/voicing parameter */
90 /* IRMS - Quantized energy parameter */
91 /* IRC - Quantized reflection coefficients */
92 /* Indices 1 through ORDER written */
93
94 /* Entry CHANRD has no local state. */
95
96
97
98 /* IBITS is 54 bits of LPC data ordered as follows: */
99 /* R1-0, R2-0, R3-0, P-0, A-0, */
100 /* R1-1, R2-1, R3-1, P-1, A-1, */
101 /* R1-2, R4-0, R3-2, A-2, P-2, R4-1, */
102 /* R1-3, R2-2, R3-3, R4-2, A-3, */
103 /* R1-4, R2-3, R3-4, R4-3, A-4, */
104 /* P-3, R2-4, R7-0, R8-0, P-4, R4-4, */
105 /* R5-0, R6-0, R7-1,R10-0, R8-1, */
106 /* R5-1, R6-1, R7-2, R9-0, P-5, */
107 /* R5-2, R6-2,R10-1, R8-2, P-6, R9-1, */
108 /* R5-3, R6-3, R7-3, R9-2, R8-3, SYNC */
chanwr_0_(int n__,integer * order,integer * ipitv,integer * irms,integer * irc,integer * ibits,struct lpc10_encoder_state * st)109 static int chanwr_0_(int n__, integer *order, integer *ipitv,
110 integer *irms, integer *irc, integer *ibits,
111 struct lpc10_encoder_state *st)
112 {
113 /* Initialized data */
114
115 integer *isync;
116 static integer bit[10] = { 2,4,8,8,8,8,16,16,16,16 };
117 static integer iblist[53] = { 13,12,11,1,2,13,12,11,1,2,13,10,11,2,1,10,
118 13,12,11,10,2,13,12,11,10,2,1,12,7,6,1,10,9,8,7,4,6,9,8,7,5,1,9,8,
119 4,6,1,5,9,8,7,5,6 };
120
121 /* System generated locals */
122 integer i__1;
123
124 /* Local variables */
125 integer itab[13], i__;
126
127 /* Arguments */
128 /* Parameters/constants */
129 /* These arrays are not Fortran PARAMETER's, but they are defined */
130 /* by DATA statements below, and their contents are never altered.
131 */
132 /* Local variables that need not be saved */
133 /* Local state */
134 /* ISYNC is only used by CHANWR, not by ENTRY CHANRD. */
135
136 /* Parameter adjustments */
137 --irc;
138 --ibits;
139
140 /* Function Body */
141 switch(n__) {
142 case 1: goto L_chanrd;
143 }
144
145 isync = &(st->isync);
146
147 /* ***********************************************************************
148 */
149 /* Place quantized parameters into bitstream */
150 /* ***********************************************************************
151 */
152 /* Place parameters into ITAB */
153 itab[0] = *ipitv;
154 itab[1] = *irms;
155 itab[2] = 0;
156 i__1 = *order;
157 for (i__ = 1; i__ <= i__1; ++i__) {
158 itab[i__ + 2] = irc[*order + 1 - i__] & 32767;
159 }
160 /* Put 54 bits into IBITS array */
161 for (i__ = 1; i__ <= 53; ++i__) {
162 ibits[i__] = itab[iblist[i__ - 1] - 1] & 1;
163 itab[iblist[i__ - 1] - 1] /= 2;
164 }
165 ibits[54] = *isync & 1;
166 *isync = 1 - *isync;
167 return 0;
168 /* ***********************************************************************
169 */
170 /* Reconstruct parameters from bitstream */
171 /* ***********************************************************************
172 */
173
174 L_chanrd:
175 /* Reconstruct ITAB */
176 for (i__ = 1; i__ <= 13; ++i__) {
177 itab[i__ - 1] = 0;
178 }
179 for (i__ = 1; i__ <= 53; ++i__) {
180 itab[iblist[54 - i__ - 1] - 1] = (itab[iblist[54 - i__ - 1] - 1] << 1)
181 + ibits[54 - i__];
182 }
183 /* Sign extend RC's */
184 i__1 = *order;
185 for (i__ = 1; i__ <= i__1; ++i__) {
186 if ((itab[i__ + 2] & bit[i__ - 1]) != 0) {
187 itab[i__ + 2] -= bit[i__ - 1] << 1;
188 }
189 }
190 /* Restore variables */
191 *ipitv = itab[0];
192 *irms = itab[1];
193 i__1 = *order;
194 for (i__ = 1; i__ <= i__1; ++i__) {
195 irc[i__] = itab[*order + 4 - i__ - 1];
196 }
197 return 0;
198 } /* chanwr_ */
199
chanwr_(integer * order,integer * ipitv,integer * irms,integer * irc,integer * ibits,struct lpc10_encoder_state * st)200 /* Subroutine */ int chanwr_(integer *order, integer *ipitv, integer *irms,
201 integer *irc, integer *ibits, struct lpc10_encoder_state *st)
202 {
203 return chanwr_0_(0, order, ipitv, irms, irc, ibits, st);
204 }
205
chanrd_(integer * order,integer * ipitv,integer * irms,integer * irc,integer * ibits)206 /* Subroutine */ int chanrd_(integer *order, integer *ipitv, integer *irms,
207 integer *irc, integer *ibits)
208 {
209 return chanwr_0_(1, order, ipitv, irms, irc, ibits, 0);
210 }
211