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/*
* ac3.h
*
* Copyright (C) Aaron Holtzman - May 1999
*
* This file is part of ac3dec, a free Dolby AC-3 stream decoder.
*
* ac3dec is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* ac3dec 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Make; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
*/
typedef struct ac3_ba_s {
uint16_t fsnroffst; // fine SNR offset
uint16_t fgaincod; // fast gain
uint16_t deltbae; // delta bit allocation exists
int8_t deltba[50]; // per-band delta bit allocation
} ac3_ba_t;
typedef struct ac3_state_s {
uint8_t fscod; // sample rate
uint8_t halfrate; // halfrate factor
uint8_t acmod; // coded channels
float clev; // centre channel mix level
float slev; // surround channels mix level
uint8_t lfeon; // coded lfe channel
int output; // type of output
float level; // output level
float bias; // output bias
uint16_t cplinu; // coupling in use
uint16_t chincpl[5]; // channel coupled
uint16_t phsflginu; // phase flags in use (stereo only)
uint16_t cplbndstrc[18]; // coupling band structure
uint16_t cplstrtmant; // coupling channel start mantissa
uint16_t cplendmant; // coupling channel end mantissa
float cplco[5][18]; // coupling coordinates
// derived information
uint16_t cplstrtbnd; // coupling start band (for bit allocation)
uint16_t ncplbnd; // number of coupling bands
uint16_t rematflg[4]; // stereo rematrixing
uint16_t endmant[5]; // channel end mantissa
uint8_t cpl_exp[256]; // decoded coupling channel exponents
uint8_t fbw_exp[5][256]; // decoded channel exponents
uint8_t lfe_exp[7]; // decoded lfe channel exponents
uint16_t sdcycod; // slow decay
uint16_t fdcycod; // fast decay
uint16_t sgaincod; // slow gain
uint16_t dbpbcod; // dB per bit - encodes the dbknee value
uint16_t floorcod; // masking floor
uint16_t csnroffst; // coarse SNR offset
ac3_ba_t cplba; // coupling bit allocation parameters
ac3_ba_t ba[5]; // channel bit allocation parameters
ac3_ba_t lfeba; // lfe bit allocation parameters
uint16_t cplfleak; // coupling fast leak init
uint16_t cplsleak; // coupling slow leak init
// derived bit allocation information
int8_t fbw_bap[5][256];
int8_t cpl_bap[256];
int8_t lfe_bap[7];
} ac3_state_t;
/* samples work structure */
typedef float stream_samples_t[6][256];
#define AC3_CHANNEL 0
#define AC3_MONO 1
#define AC3_STEREO 2
#define AC3_3F 3
#define AC3_2F1R 4
#define AC3_3F1R 5
#define AC3_2F2R 6
#define AC3_3F2R 7
#define AC3_CHANNEL1 8
#define AC3_CHANNEL2 9
#define AC3_DOLBY 10
#define AC3_CHANNEL_MASK 15
#define AC3_LFE 16
#define AC3_ADJUST_LEVEL 32
void ac3_init (void);
int ac3_syncinfo (uint8_t * buf, int * flags,
int * sample_rate, int * bit_rate);
int ac3_frame (ac3_state_t * state, uint8_t * buf, int * flags,
float * level, float bias);
int ac3_block (ac3_state_t * state);
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