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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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