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/*
* Common code between AC3 encoder and decoder
* Copyright (c) 2000, 2001, 2002 Fabrice Bellard.
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define AC3_MAX_CODED_FRAME_SIZE 3840 /* in bytes */
#define AC3_MAX_CHANNELS 6 /* including LFE channel */
#define NB_BLOCKS 6 /* number of PCM blocks inside an AC3 frame */
#define AC3_FRAME_SIZE (NB_BLOCKS * 256)
/* exponent encoding strategy */
#define EXP_REUSE 0
#define EXP_NEW 1
#define EXP_D15 1
#define EXP_D25 2
#define EXP_D45 3
typedef struct AC3BitAllocParameters {
int fscod; /* frequency */
int halfratecod;
int sgain, sdecay, fdecay, dbknee, floor;
int cplfleak, cplsleak;
} AC3BitAllocParameters;
extern const UINT16 ac3_freqs[3];
extern const UINT16 ac3_bitratetab[19];
extern const INT16 ac3_window[256];
extern const UINT8 sdecaytab[4];
extern const UINT8 fdecaytab[4];
extern const UINT16 sgaintab[4];
extern const UINT16 dbkneetab[4];
extern const UINT16 floortab[8];
extern const UINT16 fgaintab[8];
void ac3_common_init(void);
void ac3_parametric_bit_allocation(AC3BitAllocParameters *s, UINT8 *bap,
INT8 *exp, int start, int end,
int snroffset, int fgain, int is_lfe,
int deltbae,int deltnseg,
UINT8 *deltoffst, UINT8 *deltlen, UINT8 *deltba);
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