/* * Bluetooth low-complexity, subband codec (SBC) * * Copyright (C) 2017 Aurelien Jacobs <aurel@gnuage.org> * Copyright (C) 2012-2014 Intel Corporation * Copyright (C) 2008-2010 Nokia Corporation * Copyright (C) 2004-2010 Marcel Holtmann <marcel@holtmann.org> * Copyright (C) 2004-2005 Henryk Ploetz <henryk@ploetzli.ch> * Copyright (C) 2005-2006 Brad Midgley <bmidgley@xmission.com> * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * SBC common definitions for the encoder and decoder */ #ifndef AVCODEC_SBC_H #define AVCODEC_SBC_H #include "avcodec.h" #include "libavutil/crc.h" #define MSBC_BLOCKS 15 /* sampling frequency */ #define SBC_FREQ_16000 0x00 #define SBC_FREQ_32000 0x01 #define SBC_FREQ_44100 0x02 #define SBC_FREQ_48000 0x03 /* blocks */ #define SBC_BLK_4 0x00 #define SBC_BLK_8 0x01 #define SBC_BLK_12 0x02 #define SBC_BLK_16 0x03 /* channel mode */ #define SBC_MODE_MONO 0x00 #define SBC_MODE_DUAL_CHANNEL 0x01 #define SBC_MODE_STEREO 0x02 #define SBC_MODE_JOINT_STEREO 0x03 /* allocation method */ #define SBC_AM_LOUDNESS 0x00 #define SBC_AM_SNR 0x01 /* subbands */ #define SBC_SB_4 0x00 #define SBC_SB_8 0x01 /* synchronisation words */ #define SBC_SYNCWORD 0x9C #define MSBC_SYNCWORD 0xAD /* extra bits of precision for the synthesis filter input data */ #define SBCDEC_FIXED_EXTRA_BITS 2 /* * Enforce 16 byte alignment for the data, which is supposed to be used * with SIMD optimized code. */ #define SBC_ALIGN 16 /* This structure contains an unpacked SBC frame. Yes, there is probably quite some unused space herein */ struct sbc_frame { uint8_t frequency; uint8_t blocks; enum { MONO = SBC_MODE_MONO, DUAL_CHANNEL = SBC_MODE_DUAL_CHANNEL, STEREO = SBC_MODE_STEREO, JOINT_STEREO = SBC_MODE_JOINT_STEREO } mode; uint8_t channels; enum { LOUDNESS = SBC_AM_LOUDNESS, SNR = SBC_AM_SNR } allocation; uint8_t subbands; uint8_t bitpool; uint16_t codesize; /* bit number x set means joint stereo has been used in subband x */ uint8_t joint; /* only the lower 4 bits of every element are to be used */ DECLARE_ALIGNED(SBC_ALIGN, uint32_t, scale_factor)[2][8]; /* raw integer subband samples in the frame */ DECLARE_ALIGNED(SBC_ALIGN, int32_t, sb_sample_f)[16][2][8]; /* modified subband samples */ DECLARE_ALIGNED(SBC_ALIGN, int32_t, sb_sample)[16][2][8]; const AVCRC *crc_ctx; }; uint8_t ff_sbc_crc8(const AVCRC *crc_ctx, const uint8_t *data, size_t len); void ff_sbc_calculate_bits(const struct sbc_frame *frame, int (*bits)[8]); #endif /* AVCODEC_SBC_H */