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_SPEC_H
20 #define __LC3_SPEC_H
21 
22 #include "common.h"
23 #include "tables.h"
24 #include "bwdet.h"
25 #include "ltpf.h"
26 #include "tns.h"
27 #include "sns.h"
28 
29 
30 /**
31  * Spectral quantization side data
32  */
33 typedef struct lc3_spec_side {
34     int g_idx, nq;
35     bool lsb_mode;
36 } lc3_spec_side_t;
37 
38 
39 /* ----------------------------------------------------------------------------
40  *  Encoding
41  * -------------------------------------------------------------------------- */
42 
43 /**
44  * Spectrum analysis
45  * dt, sr, nbytes  Duration, samplerate and size of the frame
46  * pitch, tns      Pitch present indication and TNS bistream data
47  * spec            Context of analysis
48  * x               Spectral coefficients, scaled as output
49  * side            Return quantization data
50  */
51 void lc3_spec_analyze(
52     enum lc3_dt dt, enum lc3_srate sr, int nbytes,
53     bool pitch, const lc3_tns_data_t *tns, lc3_spec_analysis_t *spec,
54     float *x, lc3_spec_side_t *side);
55 
56 /**
57  * Put spectral quantization side data
58  * bits            Bitstream context
59  * dt, sr          Duration and samplerate of the frame
60  * side            Spectral quantization side data
61  */
62 void lc3_spec_put_side(lc3_bits_t *bits,
63     enum lc3_dt dt, enum lc3_srate sr, const lc3_spec_side_t *side);
64 
65 /**
66  * Encode spectral coefficients
67  * bits            Bitstream context
68  * dt, sr, bw      Duration, samplerate, bandwidth
69  * nbytes          and size of the frame
70  * side, x         Quantization data, and scaled coefficients
71  */
72 void lc3_spec_encode(lc3_bits_t *bits,
73     enum lc3_dt dt, enum lc3_srate sr, enum lc3_bandwidth bw,
74     int nbytes, const lc3_spec_side_t *side, float *x);
75 
76 
77 /* ----------------------------------------------------------------------------
78  *  Decoding
79  * -------------------------------------------------------------------------- */
80 
81 /**
82  * Get spectral quantization side data
83  * bits            Bitstream context
84  * dt, sr          Duration and samplerate of the frame
85  * side            Return quantization side data
86  * return          0: Ok  -1: Invalid bandwidth indication
87  */
88 int lc3_spec_get_side(lc3_bits_t *bits,
89     enum lc3_dt dt, enum lc3_srate sr, lc3_spec_side_t *side);
90 
91 /**
92  * Decode spectral coefficients
93  * bits            Bitstream context
94  * dt, sr, bw      Duration, samplerate, bandwidth
95  * nbytes          and size of the frame
96  * side            Quantization side data
97  * x               Spectral coefficients
98  * return          0: Ok  -1: Invalid bitstream data
99  */
100 int lc3_spec_decode(lc3_bits_t *bits,
101     enum lc3_dt dt, enum lc3_srate sr, enum lc3_bandwidth bw,
102     int nbytes, const lc3_spec_side_t *side, float *x);
103 
104 
105 #endif /* __LC3_SPEC_H */
106