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 */ 84struct sbc_frame { 85 uint8_t frequency; 86 uint8_t blocks; 87 enum { 88 MONO = SBC_MODE_MONO, 89 DUAL_CHANNEL = SBC_MODE_DUAL_CHANNEL, 90 STEREO = SBC_MODE_STEREO, 91 JOINT_STEREO = SBC_MODE_JOINT_STEREO 92 } mode; 93 uint8_t channels; 94 enum { 95 LOUDNESS = SBC_AM_LOUDNESS, 96 SNR = SBC_AM_SNR 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 */ 106 DECLARE_ALIGNED(SBC_ALIGN, uint32_t, scale_factor)[2][8]; 107 108 /* raw integer subband samples in the frame */ 109 DECLARE_ALIGNED(SBC_ALIGN, int32_t, sb_sample_f)[16][2][8]; 110 111 /* modified subband samples */ 112 DECLARE_ALIGNED(SBC_ALIGN, int32_t, sb_sample)[16][2][8]; 113 114 const AVCRC *crc_ctx; 115}; 116 117uint8_t ff_sbc_crc8(const AVCRC *crc_ctx, const uint8_t *data, size_t len); 118void ff_sbc_calculate_bits(const struct sbc_frame *frame, int (*bits)[8]); 119 120#endif /* AVCODEC_SBC_H */ 121