Asterisk - The Open Source Telephony Project  18.5.0
table.c
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1 /*
2  * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
3  * Universitaet Berlin. See the accompanying file "COPYRIGHT" for
4  * details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
5  */
6 
7 /* $Header$ */
8 
9 /* Most of these tables are inlined at their point of use.
10  */
11 
12 /* 4.4 TABLES USED IN THE FIXED POINT IMPLEMENTATION OF THE RPE-LTP
13  * CODER AND DECODER
14  *
15  * (Most of them inlined, so watch out.)
16  */
17 
18 #define GSM_TABLE_C
19 #include "private.h"
20 #include "gsm.h"
21 
22 /* Table 4.1 Quantization of the Log.-Area Ratios
23  */
24 /* i 1 2 3 4 5 6 7 8 */
25 word gsm_A[8] = {20480, 20480, 20480, 20480, 13964, 15360, 8534, 9036};
26 word gsm_B[8] = { 0, 0, 2048, -2560, 94, -1792, -341, -1144};
27 word gsm_MIC[8] = { -32, -32, -16, -16, -8, -8, -4, -4 };
28 word gsm_MAC[8] = { 31, 31, 15, 15, 7, 7, 3, 3 };
29 
30 
31 /* Table 4.2 Tabulation of 1/A[1..8]
32  */
33 word gsm_INVA[8]={ 13107, 13107, 13107, 13107, 19223, 17476, 31454, 29708 };
34 
35 
36 /* Table 4.3a Decision level of the LTP gain quantizer
37  */
38 /* bc 0 1 2 3 */
39 word gsm_DLB[4] = { 6554, 16384, 26214, 32767 };
40 
41 
42 /* Table 4.3b Quantization levels of the LTP gain quantizer
43  */
44 /* bc 0 1 2 3 */
45 word gsm_QLB[4] = { 3277, 11469, 21299, 32767 };
46 
47 
48 /* Table 4.4 Coefficients of the weighting filter
49  */
50 /* i 0 1 2 3 4 5 6 7 8 9 10 */
51 word gsm_H[11] = {-134, -374, 0, 2054, 5741, 8192, 5741, 2054, 0, -374, -134 };
52 
53 
54 /* Table 4.5 Normalized inverse mantissa used to compute xM/xmax
55  */
56 /* i 0 1 2 3 4 5 6 7 */
57 word gsm_NRFAC[8] = { 29128, 26215, 23832, 21846, 20165, 18725, 17476, 16384 };
58 
59 
60 /* Table 4.6 Normalized direct mantissa used to compute xM/xmax
61  */
62 /* i 0 1 2 3 4 5 6 7 */
63 word gsm_FAC[8] = { 18431, 20479, 22527, 24575, 26623, 28671, 30719, 32767 };
word gsm_INVA[8]
Definition: table.c:33
word gsm_QLB[4]
Definition: table.c:45
word gsm_DLB[4]
Definition: table.c:39
word gsm_MIC[8]
Definition: table.c:27
word gsm_FAC[8]
Definition: table.c:63
word gsm_B[8]
Definition: table.c:26
word gsm_MAC[8]
Definition: table.c:28
word gsm_NRFAC[8]
Definition: table.c:57
word gsm_A[8]
Definition: table.c:25
word gsm_H[11]
Definition: table.c:51
short word