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author | Sean Bartell <wingedtachikoma@gmail.com> | 2011-06-25 21:32:25 -0400 |
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committer | Nils Wallménius <nils@rockbox.org> | 2012-04-25 22:13:20 +0200 |
commit | f40bfc9267b13b54e6379dfe7539447662879d24 (patch) | |
tree | 9b20069d5e62809ff434061ad730096836f916f2 /lib/rbcodec/codecs/libwmavoice/lsp.c | |
parent | a0009907de7a0107d49040d8a180f140e2eff299 (diff) | |
download | rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.tar.gz rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.zip |
Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
Diffstat (limited to 'lib/rbcodec/codecs/libwmavoice/lsp.c')
-rw-r--r-- | lib/rbcodec/codecs/libwmavoice/lsp.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libwmavoice/lsp.c b/lib/rbcodec/codecs/libwmavoice/lsp.c new file mode 100644 index 0000000000..4dba9c1df9 --- /dev/null +++ b/lib/rbcodec/codecs/libwmavoice/lsp.c | |||
@@ -0,0 +1,174 @@ | |||
1 | /* | ||
2 | * LSP routines for ACELP-based codecs | ||
3 | * | ||
4 | * Copyright (c) 2007 Reynaldo H. Verdejo Pinochet (QCELP decoder) | ||
5 | * Copyright (c) 2008 Vladimir Voroshilov | ||
6 | * | ||
7 | * This file is part of FFmpeg. | ||
8 | * | ||
9 | * FFmpeg is free software; you can redistribute it and/or | ||
10 | * modify it under the terms of the GNU Lesser General Public | ||
11 | * License as published by the Free Software Foundation; either | ||
12 | * version 2.1 of the License, or (at your option) any later version. | ||
13 | * | ||
14 | * FFmpeg is distributed in the hope that it will be useful, | ||
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
17 | * Lesser General Public License for more details. | ||
18 | * | ||
19 | * You should have received a copy of the GNU Lesser General Public | ||
20 | * License along with FFmpeg; if not, write to the Free Software | ||
21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
22 | */ | ||
23 | |||
24 | #include <inttypes.h> | ||
25 | |||
26 | #include "avcodec.h" | ||
27 | #define FRAC_BITS 14 | ||
28 | #include "mathops.h" | ||
29 | #include "lsp.h" | ||
30 | #include "celp_math.h" | ||
31 | |||
32 | void ff_acelp_reorder_lsf(int16_t* lsfq, int lsfq_min_distance, int lsfq_min, int lsfq_max, int lp_order) | ||
33 | { | ||
34 | int i, j; | ||
35 | |||
36 | /* sort lsfq in ascending order. float bubble agorithm, | ||
37 | O(n) if data already sorted, O(n^2) - otherwise */ | ||
38 | for(i=0; i<lp_order-1; i++) | ||
39 | for(j=i; j>=0 && lsfq[j] > lsfq[j+1]; j--) | ||
40 | FFSWAP(int16_t, lsfq[j], lsfq[j+1]); | ||
41 | |||
42 | for(i=0; i<lp_order; i++) | ||
43 | { | ||
44 | lsfq[i] = FFMAX(lsfq[i], lsfq_min); | ||
45 | lsfq_min = lsfq[i] + lsfq_min_distance; | ||
46 | } | ||
47 | lsfq[lp_order-1] = FFMIN(lsfq[lp_order-1], lsfq_max);//Is warning required ? | ||
48 | } | ||
49 | |||
50 | void ff_set_min_dist_lsf(float *lsf, double min_spacing, int size) | ||
51 | { | ||
52 | int i; | ||
53 | float prev = 0.0; | ||
54 | for (i = 0; i < size; i++) | ||
55 | prev = lsf[i] = FFMAX(lsf[i], prev + min_spacing); | ||
56 | } | ||
57 | |||
58 | void ff_acelp_lsf2lsp(int16_t *lsp, const int16_t *lsf, int lp_order) | ||
59 | { | ||
60 | int i; | ||
61 | |||
62 | /* Convert LSF to LSP, lsp=cos(lsf) */ | ||
63 | for(i=0; i<lp_order; i++) | ||
64 | // 20861 = 2.0 / PI in (0.15) | ||
65 | lsp[i] = ff_cos(lsf[i] * 20861 >> 15); // divide by PI and (0,13) -> (0,14) | ||
66 | } | ||
67 | |||
68 | /** | ||
69 | * \brief decodes polynomial coefficients from LSP | ||
70 | * \param f [out] decoded polynomial coefficients (-0x20000000 <= (3.22) <= 0x1fffffff) | ||
71 | * \param lsp LSP coefficients (-0x8000 <= (0.15) <= 0x7fff) | ||
72 | */ | ||
73 | static void lsp2poly(int* f, const int16_t* lsp, int lp_half_order) | ||
74 | { | ||
75 | int i, j; | ||
76 | |||
77 | f[0] = 0x400000; // 1.0 in (3.22) | ||
78 | f[1] = -lsp[0] << 8; // *2 and (0.15) -> (3.22) | ||
79 | |||
80 | for(i=2; i<=lp_half_order; i++) | ||
81 | { | ||
82 | f[i] = f[i-2]; | ||
83 | for(j=i; j>1; j--) | ||
84 | f[j] -= MULL(f[j-1], lsp[2*i-2], FRAC_BITS) - f[j-2]; | ||
85 | |||
86 | f[1] -= lsp[2*i-2] << 8; | ||
87 | } | ||
88 | } | ||
89 | |||
90 | void ff_acelp_lsp2lpc(int16_t* lp, const int16_t* lsp, int lp_half_order) | ||
91 | { | ||
92 | int i; | ||
93 | int f1[MAX_LP_HALF_ORDER+1]; // (3.22) | ||
94 | int f2[MAX_LP_HALF_ORDER+1]; // (3.22) | ||
95 | |||
96 | lsp2poly(f1, lsp , lp_half_order); | ||
97 | lsp2poly(f2, lsp+1, lp_half_order); | ||
98 | |||
99 | /* 3.2.6 of G.729, Equations 25 and 26*/ | ||
100 | lp[0] = 4096; | ||
101 | for(i=1; i<lp_half_order+1; i++) | ||
102 | { | ||
103 | int ff1 = f1[i] + f1[i-1]; // (3.22) | ||
104 | int ff2 = f2[i] - f2[i-1]; // (3.22) | ||
105 | |||
106 | ff1 += 1 << 10; // for rounding | ||
107 | lp[i] = (ff1 + ff2) >> 11; // divide by 2 and (3.22) -> (3.12) | ||
108 | lp[(lp_half_order << 1) + 1 - i] = (ff1 - ff2) >> 11; // divide by 2 and (3.22) -> (3.12) | ||
109 | } | ||
110 | } | ||
111 | |||
112 | void ff_acelp_lp_decode(int16_t* lp_1st, int16_t* lp_2nd, const int16_t* lsp_2nd, const int16_t* lsp_prev, int lp_order) | ||
113 | { | ||
114 | int16_t lsp_1st[MAX_LP_ORDER]; // (0.15) | ||
115 | int i; | ||
116 | |||
117 | /* LSP values for first subframe (3.2.5 of G.729, Equation 24)*/ | ||
118 | for(i=0; i<lp_order; i++) | ||
119 | #ifdef G729_BITEXACT | ||
120 | lsp_1st[i] = (lsp_2nd[i] >> 1) + (lsp_prev[i] >> 1); | ||
121 | #else | ||
122 | lsp_1st[i] = (lsp_2nd[i] + lsp_prev[i]) >> 1; | ||
123 | #endif | ||
124 | |||
125 | ff_acelp_lsp2lpc(lp_1st, lsp_1st, lp_order >> 1); | ||
126 | |||
127 | /* LSP values for second subframe (3.2.5 of G.729)*/ | ||
128 | ff_acelp_lsp2lpc(lp_2nd, lsp_2nd, lp_order >> 1); | ||
129 | } | ||
130 | |||
131 | void ff_lsp2polyf(const double *lsp, double *f, int lp_half_order) | ||
132 | { | ||
133 | int i, j; | ||
134 | |||
135 | f[0] = 1.0; | ||
136 | f[1] = -2 * lsp[0]; | ||
137 | lsp -= 2; | ||
138 | for(i=2; i<=lp_half_order; i++) | ||
139 | { | ||
140 | double val = -2 * lsp[2*i]; | ||
141 | f[i] = val * f[i-1] + 2*f[i-2]; | ||
142 | for(j=i-1; j>1; j--) | ||
143 | f[j] += f[j-1] * val + f[j-2]; | ||
144 | f[1] += val; | ||
145 | } | ||
146 | } | ||
147 | |||
148 | void ff_acelp_lspd2lpc(const double *lsp, float *lpc, int lp_half_order) | ||
149 | { | ||
150 | double pa[MAX_LP_HALF_ORDER+1], qa[MAX_LP_HALF_ORDER+1]; | ||
151 | float *lpc2 = lpc + (lp_half_order << 1) - 1; | ||
152 | |||
153 | //assert(lp_half_order <= MAX_LP_HALF_ORDER); | ||
154 | |||
155 | ff_lsp2polyf(lsp, pa, lp_half_order); | ||
156 | ff_lsp2polyf(lsp + 1, qa, lp_half_order); | ||
157 | |||
158 | while (lp_half_order--) { | ||
159 | double paf = pa[lp_half_order+1] + pa[lp_half_order]; | ||
160 | double qaf = qa[lp_half_order+1] - qa[lp_half_order]; | ||
161 | |||
162 | lpc [ lp_half_order] = 0.5*(paf+qaf); | ||
163 | lpc2[-lp_half_order] = 0.5*(paf-qaf); | ||
164 | } | ||
165 | } | ||
166 | |||
167 | void ff_sort_nearly_sorted_floats(float *vals, int len) | ||
168 | { | ||
169 | int i,j; | ||
170 | |||
171 | for (i = 0; i < len - 1; i++) | ||
172 | for (j = i; j >= 0 && vals[j] > vals[j+1]; j--) | ||
173 | FFSWAP(float, vals[j], vals[j+1]); | ||
174 | } | ||