FreeCalypso > hg > gsm-codec-lib
annotate libgsmfr2/long_term.c @ 472:d80ccb3c3970
gsmefr-dlcap-sync: use DHF datum in the library
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Tue, 14 May 2024 07:30:48 +0000 |
parents | 65d3304502bd |
children |
rev | line source |
---|---|
267
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
1 /* |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
2 * This C source file has been adapted from TU-Berlin libgsm source, |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
3 * original notice follows: |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
4 * |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
5 * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
6 * Universitaet Berlin. See the accompanying file "COPYRIGHT" for |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
7 * details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE. |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
8 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
9 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
10 #include <stdint.h> |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
11 #include <assert.h> |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
12 #include "tw_gsmfr.h" |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
13 #include "typedef.h" |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
14 #include "ed_state.h" |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
15 #include "ed_internal.h" |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
16 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
17 /* |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
18 * 4.2.11 .. 4.2.12 LONG TERM PREDICTOR (LTP) SECTION |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
19 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
20 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
21 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
22 /* |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
23 * This module computes the LTP gain (bc) and the LTP lag (Nc) |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
24 * for the long term analysis filter. This is done by calculating a |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
25 * maximum of the cross-correlation function between the current |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
26 * sub-segment short term residual signal d[0..39] (output of |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
27 * the short term analysis filter; for simplification the index |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
28 * of this array begins at 0 and ends at 39 for each sub-segment of the |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
29 * RPE-LTP analysis) and the previous reconstructed short term |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
30 * residual signal dp[ -120 .. -1 ]. A dynamic scaling must be |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
31 * performed to avoid overflow. |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
32 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
33 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
34 static void Calculation_of_the_LTP_parameters ( |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
35 register word * d, /* [0..39] IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
36 register word * dp, /* [-120..-1] IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
37 word * bc_out, /* OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
38 word * Nc_out /* OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
39 ) |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
40 { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
41 register int k, lambda; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
42 word Nc, bc; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
43 word wt[40]; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
44 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
45 longword L_max, L_power; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
46 word R, S, dmax, scal; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
47 register word temp; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
48 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
49 /* Search of the optimum scaling of d[0..39]. |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
50 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
51 dmax = 0; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
52 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
53 for (k = 0; k <= 39; k++) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
54 temp = d[k]; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
55 temp = GSM_ABS( temp ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
56 if (temp > dmax) dmax = temp; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
57 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
58 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
59 temp = 0; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
60 if (dmax == 0) scal = 0; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
61 else { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
62 assert(dmax > 0); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
63 temp = gsm_norm( (longword)dmax << 16 ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
64 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
65 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
66 if (temp > 6) scal = 0; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
67 else scal = 6 - temp; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
68 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
69 assert(scal >= 0); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
70 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
71 /* Initialization of a working array wt |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
72 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
73 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
74 for (k = 0; k <= 39; k++) wt[k] = SASR( d[k], scal ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
75 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
76 /* Search for the maximum cross-correlation and coding of the LTP lag |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
77 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
78 L_max = 0; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
79 Nc = 40; /* index for the maximum cross-correlation */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
80 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
81 for (lambda = 40; lambda <= 120; lambda++) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
82 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
83 # undef STEP |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
84 # define STEP(k) (longword)wt[k] * dp[k - lambda] |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
85 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
86 register longword L_result; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
87 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
88 L_result = STEP(0) ; L_result += STEP(1) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
89 L_result += STEP(2) ; L_result += STEP(3) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
90 L_result += STEP(4) ; L_result += STEP(5) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
91 L_result += STEP(6) ; L_result += STEP(7) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
92 L_result += STEP(8) ; L_result += STEP(9) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
93 L_result += STEP(10) ; L_result += STEP(11) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
94 L_result += STEP(12) ; L_result += STEP(13) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
95 L_result += STEP(14) ; L_result += STEP(15) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
96 L_result += STEP(16) ; L_result += STEP(17) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
97 L_result += STEP(18) ; L_result += STEP(19) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
98 L_result += STEP(20) ; L_result += STEP(21) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
99 L_result += STEP(22) ; L_result += STEP(23) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
100 L_result += STEP(24) ; L_result += STEP(25) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
101 L_result += STEP(26) ; L_result += STEP(27) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
102 L_result += STEP(28) ; L_result += STEP(29) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
103 L_result += STEP(30) ; L_result += STEP(31) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
104 L_result += STEP(32) ; L_result += STEP(33) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
105 L_result += STEP(34) ; L_result += STEP(35) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
106 L_result += STEP(36) ; L_result += STEP(37) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
107 L_result += STEP(38) ; L_result += STEP(39) ; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
108 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
109 if (L_result > L_max) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
110 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
111 Nc = lambda; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
112 L_max = L_result; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
113 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
114 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
115 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
116 *Nc_out = Nc; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
117 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
118 L_max <<= 1; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
119 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
120 /* Rescaling of L_max |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
121 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
122 assert(scal <= 100 && scal >= -100); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
123 L_max = L_max >> (6 - scal); /* sub(6, scal) */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
124 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
125 assert( Nc <= 120 && Nc >= 40); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
126 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
127 /* Compute the power of the reconstructed short term residual |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
128 * signal dp[..] |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
129 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
130 L_power = 0; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
131 for (k = 0; k <= 39; k++) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
132 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
133 register longword L_temp; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
134 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
135 L_temp = SASR( dp[k - Nc], 3 ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
136 L_power += L_temp * L_temp; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
137 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
138 L_power <<= 1; /* from L_MULT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
139 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
140 /* Normalization of L_max and L_power |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
141 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
142 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
143 if (L_max <= 0) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
144 *bc_out = 0; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
145 return; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
146 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
147 if (L_max >= L_power) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
148 *bc_out = 3; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
149 return; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
150 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
151 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
152 temp = gsm_norm( L_power ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
153 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
154 R = SASR( L_max << temp, 16 ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
155 S = SASR( L_power << temp, 16 ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
156 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
157 /* Coding of the LTP gain |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
158 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
159 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
160 /* Table 4.3a must be used to obtain the level DLB[i] for the |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
161 * quantization of the LTP gain b to get the coded version bc. |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
162 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
163 for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
164 *bc_out = bc; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
165 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
166 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
167 /* 4.2.12 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
168 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
169 static void Long_term_analysis_filtering ( |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
170 word bc, /* IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
171 word Nc, /* IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
172 register word * dp, /* previous d [-120..-1] IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
173 register word * d, /* d [0..39] IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
174 register word * dpp, /* estimate [0..39] OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
175 register word * e /* long term res. signal [0..39] OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
176 ) |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
177 /* |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
178 * In this part, we have to decode the bc parameter to compute |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
179 * the samples of the estimate dpp[0..39]. The decoding of bc needs the |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
180 * use of table 4.3b. The long term residual signal e[0..39] |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
181 * is then calculated to be fed to the RPE encoding section. |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
182 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
183 { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
184 register int k; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
185 register longword ltmp; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
186 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
187 # undef STEP |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
188 # define STEP(BP) \ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
189 for (k = 0; k <= 39; k++) { \ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
190 dpp[k] = GSM_MULT_R( BP, dp[k - Nc]); \ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
191 e[k] = GSM_SUB( d[k], dpp[k] ); \ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
192 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
193 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
194 switch (bc) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
195 case 0: STEP( 3277 ); break; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
196 case 1: STEP( 11469 ); break; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
197 case 2: STEP( 21299 ); break; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
198 case 3: STEP( 32767 ); break; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
199 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
200 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
201 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
202 void Gsm_Long_Term_Predictor ( /* 4x for 160 samples */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
203 struct gsmfr_0610_state * S, |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
204 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
205 word * d, /* [0..39] residual signal IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
206 word * dp, /* [-120..-1] d' IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
207 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
208 word * e, /* [0..39] OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
209 word * dpp, /* [0..39] OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
210 word * Nc, /* correlation lag OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
211 word * bc /* gain factor OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
212 ) |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
213 { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
214 assert( d ); assert( dp ); assert( e ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
215 assert( dpp); assert( Nc ); assert( bc ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
216 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
217 Calculation_of_the_LTP_parameters(d, dp, bc, Nc); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
218 Long_term_analysis_filtering( *bc, *Nc, dp, d, dpp, e ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
219 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
220 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
221 /* 4.3.2 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
222 void Gsm_Long_Term_Synthesis_Filtering ( |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
223 struct gsmfr_0610_state * S, |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
224 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
225 word Ncr, |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
226 word bcr, |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
227 register word * erp, /* [0..39] IN */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
228 register word * drp /* [-120..-1] IN, [-120..40] OUT */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
229 ) |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
230 /* |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
231 * This procedure uses the bcr and Ncr parameter to realize the |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
232 * long term synthesis filtering. The decoding of bcr needs |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
233 * table 4.3b. |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
234 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
235 { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
236 register longword ltmp; /* for ADD */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
237 register int k; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
238 word brp, drpp, Nr; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
239 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
240 /* Check the limits of Nr. |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
241 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
242 Nr = Ncr < 40 || Ncr > 120 ? S->nrp : Ncr; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
243 S->nrp = Nr; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
244 assert(Nr >= 40 && Nr <= 120); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
245 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
246 /* Decoding of the LTP gain bcr |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
247 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
248 brp = gsm_QLB[ bcr ]; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
249 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
250 /* Computation of the reconstructed short term residual |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
251 * signal drp[0..39] |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
252 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
253 assert(brp != MIN_WORD); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
254 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
255 for (k = 0; k <= 39; k++) { |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
256 drpp = GSM_MULT_R( brp, drp[ k - Nr ] ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
257 drp[k] = GSM_ADD( erp[k], drpp ); |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
258 } |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
259 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
260 /* |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
261 * Update of the reconstructed short term residual signal |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
262 * drp[ -1..-120 ] |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
263 */ |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
264 |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
265 for (k = 0; k <= 119; k++) drp[ -120 + k ] = drp[ -80 + k ]; |
65d3304502bd
libgsmfr2: integrate long_term.c from libgsm
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
|
266 } |