1 /******************************************************************************
2 *
3 * Copyright 2022 Google LLC
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 ******************************************************************************/
18
19 #ifndef __LC3_TABLES_H
20 #define __LC3_TABLES_H
21
22 #include "common.h"
23 #include "bits.h"
24
25
26 /**
27 * Characteristics
28 *
29 * ns Number of temporal samples / frequency coefficients within a frame
30 *
31 * ne Number of encoded frequency coefficients
32 *
33 * nd Number of MDCT delayed samples, sum of half a frame and an ovelap
34 * of future by 1.25 ms (2.5ms, 5ms and 10ms frame durations),
35 * or 2 ms (7.5ms frame duration).
36 *
37 * nh Number of 18 ms samples of the history buffer, aligned on a frame
38 *
39 * nt Number of 1.25 ms previous samples
40 */
41
42 extern const int lc3_ns_2m5[LC3_NUM_SRATE];
43 extern const int lc3_ne_2m5[LC3_NUM_SRATE];
44 extern const int lc3_ns_4m [LC3_NUM_SRATE];
45
lc3_ns(enum lc3_dt dt,enum lc3_srate sr)46 static inline int lc3_ns(enum lc3_dt dt, enum lc3_srate sr) {
47 return lc3_ns_2m5[sr] * (1 + dt);
48 }
49
lc3_ne(enum lc3_dt dt,enum lc3_srate sr)50 static inline int lc3_ne(enum lc3_dt dt, enum lc3_srate sr) {
51 return lc3_ne_2m5[sr] * (1 + dt);
52 }
53
lc3_nd(enum lc3_dt dt,enum lc3_srate sr)54 static inline int lc3_nd(enum lc3_dt dt, enum lc3_srate sr) {
55 return ( lc3_ns(dt, sr) +
56 (dt == LC3_DT_7M5 ? lc3_ns_4m[sr] : lc3_ns_2m5[sr]) ) >> 1;
57 }
58
lc3_nh(enum lc3_dt dt,enum lc3_srate sr)59 static inline int lc3_nh(enum lc3_dt dt, enum lc3_srate sr) {
60 return sr > LC3_SRATE_48K_HR ? 0 :
61 (8 + (dt == LC3_DT_7M5)) * lc3_ns_2m5[sr];
62 }
63
lc3_nt(enum lc3_srate sr)64 static inline int lc3_nt(enum lc3_srate sr) {
65 return lc3_ns_2m5[sr] >> 1;
66 }
67
68 #define LC3_MAX_SRATE_HZ ( LC3_PLUS_HR ? 96000 : 48000 )
69
70 #define LC3_MAX_NS ( LC3_NS(10000, LC3_MAX_SRATE_HZ) )
71 #define LC3_MAX_NE ( LC3_PLUS_HR ? LC3_MAX_NS : LC3_NS(10000, 40000) )
72
73
74 /**
75 * Limits on size of frame
76 */
77
78 extern const int lc3_frame_bytes_hr_lim
79 [LC3_NUM_DT][LC3_NUM_SRATE - LC3_SRATE_48K_HR][2];
80
lc3_min_frame_bytes(enum lc3_dt dt,enum lc3_srate sr)81 static inline int lc3_min_frame_bytes(enum lc3_dt dt, enum lc3_srate sr) {
82 return !lc3_hr(sr) ? LC3_MIN_FRAME_BYTES :
83 lc3_frame_bytes_hr_lim[dt][sr - LC3_SRATE_48K_HR][0];
84 }
85
lc3_max_frame_bytes(enum lc3_dt dt,enum lc3_srate sr)86 static inline int lc3_max_frame_bytes(enum lc3_dt dt, enum lc3_srate sr) {
87 return !lc3_hr(sr) ? LC3_MAX_FRAME_BYTES :
88 lc3_frame_bytes_hr_lim[dt][sr - LC3_SRATE_48K_HR][1];
89 }
90
91
92 /**
93 * MDCT Twiddles and window coefficients
94 */
95
96 struct lc3_fft_bf3_twiddles { int n3; const struct lc3_complex (*t)[2]; };
97 struct lc3_fft_bf2_twiddles { int n2; const struct lc3_complex *t; };
98 struct lc3_mdct_rot_def { int n4; const struct lc3_complex *w; };
99
100 extern const struct lc3_fft_bf3_twiddles *lc3_fft_twiddles_bf3[];
101 extern const struct lc3_fft_bf2_twiddles *lc3_fft_twiddles_bf2[][3];
102 extern const struct lc3_mdct_rot_def *lc3_mdct_rot[LC3_NUM_DT][LC3_NUM_SRATE];
103
104 extern const float *lc3_mdct_win[LC3_NUM_DT][LC3_NUM_SRATE];
105
106
107 /**
108 * Limits of bands
109 */
110
111 #define LC3_MAX_BANDS 64
112
113 extern const int lc3_num_bands[LC3_NUM_DT][LC3_NUM_SRATE];
114 extern const int *lc3_band_lim[LC3_NUM_DT][LC3_NUM_SRATE];
115
116
117 /**
118 * SNS Quantization
119 */
120
121 extern const float lc3_sns_lfcb[32][8];
122 extern const float lc3_sns_hfcb[32][8];
123
124 struct lc3_sns_vq_gains {
125 int count; const float *v;
126 };
127
128 extern const struct lc3_sns_vq_gains lc3_sns_vq_gains[4];
129
130 extern const int32_t lc3_sns_mpvq_offsets[][11];
131
132
133 /**
134 * TNS Arithmetic Coding
135 */
136
137 extern const struct lc3_ac_model lc3_tns_order_models[];
138 extern const uint16_t lc3_tns_order_bits[][8];
139
140 extern const struct lc3_ac_model lc3_tns_coeffs_models[];
141 extern const uint16_t lc3_tns_coeffs_bits[][17];
142
143
144 /**
145 * Long Term Postfilter
146 */
147
148 extern const float *lc3_ltpf_cnum[LC3_NUM_SRATE][4];
149 extern const float *lc3_ltpf_cden[LC3_NUM_SRATE][4];
150
151
152 /**
153 * Spectral Data Arithmetic Coding
154 */
155
156 extern const uint8_t lc3_spectrum_lookup[2][2][256][4];
157 extern const struct lc3_ac_model lc3_spectrum_models[];
158 extern const uint16_t lc3_spectrum_bits[][17];
159
160
161 #endif /* __LC3_TABLES_H */
162
