annotate libtwamr/residu.c @ 556:18aca50d68df default tip

doc/Calypso-TCH-downlink: update for FR1 BFI-with-data
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 11 Oct 2024 01:54:00 +0000
parents a2351f2ad4f8
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
393
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 *
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 * R99 Version 3.3.0
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 * REL-4 Version 4.1.0
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 *
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 *
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 * File : residu.c
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 * Purpose : Computes the LP residual.
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 * Description : The LP residual is computed by filtering the input
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 * : speech through the LP inverse filter A(z).
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 *
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 /*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 * MODULE INCLUDE FILE AND VERSION ID
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 #include "namespace.h"
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23 #include "residu.h"
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
24
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 /*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27 * INCLUDE FILES
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30 #include "typedef.h"
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31 #include "basic_op.h"
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32 #include "no_count.h"
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 #include "cnst.h"
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
34
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
35 /*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
36 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
37 * LOCAL VARIABLES AND TABLES
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
38 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
39 */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
40 /*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
41 *--------------------------------------*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
42 * Constants (defined in cnst.h *
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
43 *--------------------------------------*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
44 * M : LPC order *
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
45 *--------------------------------------*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
46 */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
47
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
48 /*
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
49 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
50 * PUBLIC PROGRAM CODE
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
51 ********************************************************************************
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
52 */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
53 void Residu (
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
54 Word16 a[], /* (i) : prediction coefficients */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
55 Word16 x[], /* (i) : speech signal */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
56 Word16 y[], /* (o) : residual signal */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
57 Word16 lg /* (i) : size of filtering */
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
58 )
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
59 {
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
60 Word16 i, j;
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
61 Word32 s;
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
62
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
63 for (i = 0; i < lg; i++)
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
64 {
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
65 s = L_mult (x[i], a[0]);
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
66 for (j = 1; j <= M; j++)
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
67 {
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
68 s = L_mac (s, a[j], x[i - j]);
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
69 }
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
70 s = L_shl (s, 3);
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
71 y[i] = round (s); move16 ();
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
72 }
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
73 return;
a2351f2ad4f8 libtwamr: integrate residu.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
74 }