FFmpeg
sbc.h
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1 /*
2  * Bluetooth low-complexity, subband codec (SBC)
3  *
4  * Copyright (C) 2017 Aurelien Jacobs <aurel@gnuage.org>
5  * Copyright (C) 2012-2014 Intel Corporation
6  * Copyright (C) 2008-2010 Nokia Corporation
7  * Copyright (C) 2004-2010 Marcel Holtmann <marcel@holtmann.org>
8  * Copyright (C) 2004-2005 Henryk Ploetz <henryk@ploetzli.ch>
9  * Copyright (C) 2005-2006 Brad Midgley <bmidgley@xmission.com>
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * SBC common definitions for the encoder and decoder
31  */
32 
33 #ifndef AVCODEC_SBC_H
34 #define AVCODEC_SBC_H
35 
36 #include <stddef.h>
37 #include <stdint.h>
38 #include "libavutil/crc.h"
39 #include "libavutil/mem_internal.h"
40 
41 #define MSBC_BLOCKS 15
42 
43 /* sampling frequency */
44 #define SBC_FREQ_16000 0x00
45 #define SBC_FREQ_32000 0x01
46 #define SBC_FREQ_44100 0x02
47 #define SBC_FREQ_48000 0x03
48 
49 /* blocks */
50 #define SBC_BLK_4 0x00
51 #define SBC_BLK_8 0x01
52 #define SBC_BLK_12 0x02
53 #define SBC_BLK_16 0x03
54 
55 /* channel mode */
56 #define SBC_MODE_MONO 0x00
57 #define SBC_MODE_DUAL_CHANNEL 0x01
58 #define SBC_MODE_STEREO 0x02
59 #define SBC_MODE_JOINT_STEREO 0x03
60 
61 /* allocation method */
62 #define SBC_AM_LOUDNESS 0x00
63 #define SBC_AM_SNR 0x01
64 
65 /* subbands */
66 #define SBC_SB_4 0x00
67 #define SBC_SB_8 0x01
68 
69 /* synchronisation words */
70 #define SBC_SYNCWORD 0x9C
71 #define MSBC_SYNCWORD 0xAD
72 
73 /* extra bits of precision for the synthesis filter input data */
74 #define SBCDEC_FIXED_EXTRA_BITS 2
75 
76 /*
77  * Enforce 16 byte alignment for the data, which is supposed to be used
78  * with SIMD optimized code.
79  */
80 #define SBC_ALIGN 16
81 
82 /* This structure contains an unpacked SBC frame.
83  Yes, there is probably quite some unused space herein */
84 struct sbc_frame {
85  uint8_t frequency;
86  uint8_t blocks;
87  enum {
92  } mode;
93  uint8_t channels;
94  enum {
97  } allocation;
98  uint8_t subbands;
99  uint8_t bitpool;
100  uint16_t codesize;
101 
102  /* bit number x set means joint stereo has been used in subband x */
103  uint8_t joint;
104 
105  /* only the lower 4 bits of every element are to be used */
107 
108  /* raw integer subband samples in the frame */
110 
111  /* modified subband samples */
113 
114  const AVCRC *crc_ctx;
115 };
116 
117 uint8_t ff_sbc_crc8(const AVCRC *crc_ctx, const uint8_t *data, size_t len);
118 void ff_sbc_calculate_bits(const struct sbc_frame *frame, int (*bits)[8]);
119 
120 #endif /* AVCODEC_SBC_H */
mem_internal.h
AVCRC
uint32_t AVCRC
Definition: crc.h:46
sbc_frame::DUAL_CHANNEL
@ DUAL_CHANNEL
Definition: sbc.h:89
sbc_frame::allocation
enum sbc_frame::@153 allocation
data
const char data[16]
Definition: mxf.c:148
sbc_frame::subbands
uint8_t subbands
Definition: sbc.h:98
sbc_frame::SNR
@ SNR
Definition: sbc.h:96
crc.h
sbc_frame::scale_factor
uint32_t scale_factor[2][8]
Definition: sbc.h:106
sbc_frame::JOINT_STEREO
@ JOINT_STEREO
Definition: sbc.h:91
sbc_frame::mode
enum sbc_frame::@152 mode
sbc_frame::LOUDNESS
@ LOUDNESS
Definition: sbc.h:95
sbc_frame::bitpool
uint8_t bitpool
Definition: sbc.h:99
bits
uint8_t bits
Definition: vp3data.h:128
frame
static AVFrame * frame
Definition: demux_decode.c:54
SBC_AM_SNR
#define SBC_AM_SNR
Definition: sbc.h:63
SBC_MODE_STEREO
#define SBC_MODE_STEREO
Definition: sbc.h:58
SBC_AM_LOUDNESS
#define SBC_AM_LOUDNESS
Definition: sbc.h:62
SBC_ALIGN
#define SBC_ALIGN
Definition: sbc.h:80
DECLARE_ALIGNED
#define DECLARE_ALIGNED(n, t, v)
Definition: mem_internal.h:87
sbc_frame::channels
uint8_t channels
Definition: sbc.h:93
SBC_MODE_MONO
#define SBC_MODE_MONO
Definition: sbc.h:56
sbc_frame::MONO
@ MONO
Definition: sbc.h:88
sbc_frame
Definition: sbc.h:84
sbc_frame::joint
uint8_t joint
Definition: sbc.h:103
ff_sbc_calculate_bits
void ff_sbc_calculate_bits(const struct sbc_frame *frame, int(*bits)[8])
Definition: sbc.c:78
len
int len
Definition: vorbis_enc_data.h:426
sbc_frame::STEREO
@ STEREO
Definition: sbc.h:90
sbc_frame::crc_ctx
const AVCRC * crc_ctx
Definition: sbc.h:114
sbc_frame::frequency
uint8_t frequency
Definition: sbc.h:85
ff_sbc_crc8
uint8_t ff_sbc_crc8(const AVCRC *crc_ctx, const uint8_t *data, size_t len)
Definition: sbc.c:54
sbc_frame::blocks
uint8_t blocks
Definition: sbc.h:86
SBC_MODE_DUAL_CHANNEL
#define SBC_MODE_DUAL_CHANNEL
Definition: sbc.h:57
int32_t
int32_t
Definition: audioconvert.c:56
sbc_frame::sb_sample
int32_t sb_sample[16][2][8]
Definition: sbc.h:112
SBC_MODE_JOINT_STEREO
#define SBC_MODE_JOINT_STEREO
Definition: sbc.h:59
sbc_frame::sb_sample_f
int32_t sb_sample_f[16][2][8]
Definition: sbc.h:109
sbc_frame::codesize
uint16_t codesize
Definition: sbc.h:100