www.pudn.com > mediator15src.zip > a52_internal.h

/* 
 * a52_internal.h 
 * Copyright (C) 2000-2002 Michel Lespinasse  
 * Copyright (C) 1999-2000 Aaron Holtzman  
 * 
 * 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);