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/*
* a52_internal.h
* Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org>
* Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
*
* This file is part of a52dec, a free ATSC A-52 stream decoder.
* See http://liba52.sourceforge.net/ for updates.
*
* a52dec 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 of the License, or
* (at your option) any later version.
*
* a52dec 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
typedef struct {
uint8_t bai; /* fine SNR offset, fast gain */
uint8_t deltbae; /* delta bit allocation exists */
int8_t deltba[50]; /* per-band delta bit allocation */
} ba_t;
typedef struct {
uint8_t exp[256]; /* decoded channel exponents */
int8_t bap[256]; /* derived channel bit allocation */
} expbap_t;
struct a52_state_s {
uint8_t fscod; /* sample rate */
uint8_t halfrate; /* halfrate factor */
uint8_t acmod; /* coded channels */
uint8_t lfeon; /* coded lfe channel */
sample_t clev; /* centre channel mix level */
sample_t slev; /* surround channels mix level */
int output; /* type of output */
sample_t level; /* output level */
sample_t bias; /* output bias */
int dynrnge; /* apply dynamic range */
sample_t dynrng; /* dynamic range */
void * dynrngdata; /* dynamic range callback funtion and data */
sample_t (* dynrngcall) (sample_t range, void * dynrngdata);
uint8_t chincpl; /* channel coupled */
uint8_t phsflginu; /* phase flags in use (stereo only) */
uint8_t cplstrtmant; /* coupling channel start mantissa */
uint8_t cplendmant; /* coupling channel end mantissa */
uint32_t cplbndstrc; /* coupling band structure */
sample_t cplco[5][18]; /* coupling coordinates */
/* derived information */
uint8_t cplstrtbnd; /* coupling start band (for bit allocation) */
uint8_t ncplbnd; /* number of coupling bands */
uint8_t rematflg; /* stereo rematrixing */
uint8_t endmant[5]; /* channel end mantissa */
uint16_t bai; /* bit allocation information */
uint8_t csnroffst; /* coarse SNR offset */
ba_t cplba; /* coupling bit allocation parameters */
ba_t ba[5]; /* channel bit allocation parameters */
ba_t lfeba; /* lfe bit allocation parameters */
uint8_t cplfleak; /* coupling fast leak init */
uint8_t cplsleak; /* coupling slow leak init */
expbap_t cpl_expbap;
expbap_t fbw_expbap[5];
expbap_t lfe_expbap;
sample_t * samples;
int downmixed;
};
#define LEVEL_PLUS6DB 2.0
#define LEVEL_PLUS3DB 1.4142135623730951
#define LEVEL_3DB 0.7071067811865476
#define LEVEL_45DB 0.5946035575013605
#define LEVEL_6DB 0.5
#define EXP_REUSE (0)
#define EXP_D15 (1)
#define EXP_D25 (2)
#define EXP_D45 (3)
#define DELTA_BIT_REUSE (0)
#define DELTA_BIT_NEW (1)
#define DELTA_BIT_NONE (2)
#define DELTA_BIT_RESERVED (3)
void a52_bit_allocate (a52_state_t * state, ba_t * ba, int bndstart,
int start, int end, int fastleak, int slowleak,
expbap_t * expbap);
int a52_downmix_init (int input, int flags, sample_t * level,
sample_t clev, sample_t slev);
int a52_downmix_coeff (sample_t * coeff, int acmod, int output, sample_t level,
sample_t clev, sample_t slev);
void a52_downmix (sample_t * samples, int acmod, int output, sample_t bias,
sample_t clev, sample_t slev);
void a52_upmix (sample_t * samples, int acmod, int output);
void a52_imdct_init (uint32_t mm_accel);
void a52_imdct_256 (sample_t * data, sample_t * delay, sample_t bias);
void a52_imdct_512 (sample_t * data, sample_t * delay, sample_t bias);
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