1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
/******************************************************************************
*
* Copyright 2022 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************/
/**
* LC3 - Spectral coefficients encoding/decoding
*
* Reference : Low Complexity Communication Codec (LC3)
* Bluetooth Specification v1.0
*/
#ifndef __LC3_SPEC_H
#define __LC3_SPEC_H
#include "common.h"
#include "tables.h"
#include "bwdet.h"
#include "ltpf.h"
#include "tns.h"
#include "sns.h"
/**
* Spectral quantization side data
*/
typedef struct lc3_spec_side {
int g_idx, nq;
bool lsb_mode;
} lc3_spec_side_t;
/* ----------------------------------------------------------------------------
* Encoding
* -------------------------------------------------------------------------- */
/**
* Spectrum analysis
* dt, sr, nbytes Duration, samplerate and size of the frame
* pitch, tns Pitch present indication and TNS bistream data
* spec Context of analysis
* x Spectral coefficients, scaled as output
* xq, side Return quantization data
*
* The spectral coefficients `xq` storage is :
* b0 0:positive or zero 1:negative
* b15..b1 Absolute value
*/
void lc3_spec_analyze(enum lc3_dt dt, enum lc3_srate sr,
int nbytes, bool pitch, const lc3_tns_data_t *tns,
lc3_spec_analysis_t *spec, float *x, uint16_t *xq, lc3_spec_side_t *side);
/**
* Put spectral quantization side data
* bits Bitstream context
* dt, sr Duration and samplerate of the frame
* side Spectral quantization side data
*/
void lc3_spec_put_side(lc3_bits_t *bits,
enum lc3_dt dt, enum lc3_srate sr, const lc3_spec_side_t *side);
/**
* Encode spectral coefficients
* bits Bitstream context
* dt, sr, bw Duration, samplerate, bandwidth
* nbytes and size of the frame
* xq, side Quantization data
* x Scaled spectral coefficients
*
* The spectral coefficients `xq` storage is :
* b0 0:positive or zero 1:negative
* b15..b1 Absolute value
*/
void lc3_spec_encode(lc3_bits_t *bits,
enum lc3_dt dt, enum lc3_srate sr, enum lc3_bandwidth bw, int nbytes,
const uint16_t *xq, const lc3_spec_side_t *side, const float *x);
/* ----------------------------------------------------------------------------
* Decoding
* -------------------------------------------------------------------------- */
/**
* Get spectral quantization side data
* bits Bitstream context
* dt, sr Duration and samplerate of the frame
* side Return quantization side data
* return 0: Ok -1: Invalid bandwidth indication
*/
int lc3_spec_get_side(lc3_bits_t *bits,
enum lc3_dt dt, enum lc3_srate sr, lc3_spec_side_t *side);
/**
* Decode spectral coefficients
* bits Bitstream context
* dt, sr, bw Duration, samplerate, bandwidth
* nbytes and size of the frame
* side Quantization side data
* x Spectral coefficients
* return 0: Ok -1: Invalid bitstream data
*/
int lc3_spec_decode(lc3_bits_t *bits, enum lc3_dt dt, enum lc3_srate sr,
enum lc3_bandwidth bw, int nbytes, const lc3_spec_side_t *side, float *x);
#endif /* __LC3_SPEC_H */
|
