FFmpeg  4.0
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 "avcodec.h"
37 #include "libavutil/crc.h"
38 
39 #define MSBC_BLOCKS 15
40 
41 /* sampling frequency */
42 #define SBC_FREQ_16000 0x00
43 #define SBC_FREQ_32000 0x01
44 #define SBC_FREQ_44100 0x02
45 #define SBC_FREQ_48000 0x03
46 
47 /* blocks */
48 #define SBC_BLK_4 0x00
49 #define SBC_BLK_8 0x01
50 #define SBC_BLK_12 0x02
51 #define SBC_BLK_16 0x03
52 
53 /* channel mode */
54 #define SBC_MODE_MONO 0x00
55 #define SBC_MODE_DUAL_CHANNEL 0x01
56 #define SBC_MODE_STEREO 0x02
57 #define SBC_MODE_JOINT_STEREO 0x03
58 
59 /* allocation method */
60 #define SBC_AM_LOUDNESS 0x00
61 #define SBC_AM_SNR 0x01
62 
63 /* subbands */
64 #define SBC_SB_4 0x00
65 #define SBC_SB_8 0x01
66 
67 /* synchronisation words */
68 #define SBC_SYNCWORD 0x9C
69 #define MSBC_SYNCWORD 0xAD
70 
71 /* extra bits of precision for the synthesis filter input data */
72 #define SBCDEC_FIXED_EXTRA_BITS 2
73 
74 /*
75  * Enforce 16 byte alignment for the data, which is supposed to be used
76  * with SIMD optimized code.
77  */
78 #define SBC_ALIGN 16
79 
80 /* This structure contains an unpacked SBC frame.
81  Yes, there is probably quite some unused space herein */
82 struct sbc_frame {
85  enum {
90  } mode;
92  enum {
95  } allocation;
98  uint16_t codesize;
99 
100  /* bit number x set means joint stereo has been used in subband x */
102 
103  /* only the lower 4 bits of every element are to be used */
105 
106  /* raw integer subband samples in the frame */
108 
109  /* modified subband samples */
111 
112  const AVCRC *crc_ctx;
113 };
114 
115 uint8_t ff_sbc_crc8(const AVCRC *crc_ctx, const uint8_t *data, size_t len);
116 void ff_sbc_calculate_bits(const struct sbc_frame *frame, int (*bits)[8]);
117 
118 #endif /* AVCODEC_SBC_H */
uint8_t ff_sbc_crc8(const AVCRC *crc_ctx, const uint8_t *data, size_t len)
Definition: sbc.c:55
uint16_t codesize
Definition: sbc.h:98
int32_t sb_sample_f[16][2][8]
Definition: sbc.h:107
#define SBC_AM_LOUDNESS
Definition: sbc.h:60
uint8_t
static AVFrame * frame
Public header for CRC hash function implementation.
const char data[16]
Definition: mxf.c:90
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:112
#define SBC_MODE_MONO
Definition: sbc.h:54
uint32_t scale_factor[2][8]
Definition: sbc.h:104
uint8_t bitpool
Definition: sbc.h:97
uint8_t channels
Definition: sbc.h:91
int32_t
#define SBC_MODE_JOINT_STEREO
Definition: sbc.h:57
Libavcodec external API header.
#define SBC_MODE_DUAL_CHANNEL
Definition: sbc.h:55
enum sbc_frame::@119 mode
uint8_t frequency
Definition: sbc.h:83
#define SBC_ALIGN
Definition: sbc.h:78
uint8_t joint
Definition: sbc.h:101
const AVCRC * crc_ctx
Definition: sbc.h:112
#define SBC_MODE_STEREO
Definition: sbc.h:56
void ff_sbc_calculate_bits(const struct sbc_frame *frame, int(*bits)[8])
Definition: sbc.c:79
int len
enum sbc_frame::@120 allocation
Definition: sbc.h:82
#define SBC_AM_SNR
Definition: sbc.h:61
uint8_t subbands
Definition: sbc.h:96
uint32_t AVCRC
Definition: crc.h:47
int32_t sb_sample[16][2][8]
Definition: sbc.h:110
uint8_t blocks
Definition: sbc.h:84