#ifndef AC3_H
#define AC3_H
#define MAX_AC3_FRAMESIZE 1920 * 2 + 512
//extern int mpeg3_ac3_samplerates[3];
/* Exponent strategy constants */
#define MPEG3_EXP_REUSE (0)
#define MPEG3_EXP_D15 (1)
#define MPEG3_EXP_D25 (2)
#define MPEG3_EXP_D45 (3)
/* Delta bit allocation constants */
#define DELTA_BIT_REUSE (0)
#define DELTA_BIT_NEW (1)
#define DELTA_BIT_NONE (2)
#define DELTA_BIT_RESERVED (3)
typedef float mpeg3ac3_stream_samples_t[6][256];
typedef struct
{
/* Bit stream identification == 0x8 */
int bsid;
/* Bit stream mode */
int bsmod;
/* Audio coding mode */
int acmod;
/* If we're using the centre channel then */
/* centre mix level */
int cmixlev;
/* If we're using the surround channel then */
/* surround mix level */
int surmixlev;
/* If we're in 2/0 mode then */
/* Dolby surround mix level - NOT USED - */
int dsurmod;
/* Low frequency effects on */
int lfeon;
/* Dialogue Normalization level */
int dialnorm;
/* Compression exists */
int compre;
/* Compression level */
int compr;
/* Language code exists */
int langcode;
/* Language code */
int langcod;
/* Audio production info exists*/
unsigned int audprodie;
int mixlevel;
int roomtyp;
/* If we're in dual mono mode (acmod == 0) then extra stuff */
int dialnorm2;
int compr2e;
int compr2;
int langcod2e;
int langcod2;
int audprodi2e;
int mixlevel2;
int roomtyp2;
/* Copyright bit */
int copyrightb;
/* Original bit */
int origbs;
/* Timecode 1 exists */
int timecod1e;
/* Timecode 1 */
unsigned int timecod1;
/* Timecode 2 exists */
int timecod2e;
/* Timecode 2 */
unsigned int timecod2;
/* Additional bit stream info exists */
int addbsie;
/* Additional bit stream length - 1 (in bytes) */
int addbsil;
/* Additional bit stream information (max 64 bytes) */
unsigned char addbsi[64];
/* Information not in the AC-3 bitstream, but derived */
/* Number of channels (excluding LFE)
* Derived from acmod */
int nfchans;
} mpeg3_ac3bsi_t;
typedef struct
{
/* block switch bit indexed by channel num */
unsigned short blksw[5];
/* dither enable bit indexed by channel num */
unsigned short dithflag[5];
/* dynamic range gain exists */
int dynrnge;
/* dynamic range gain */
int dynrng;
/* if acmod==0 then */
/* dynamic range 2 gain exists */
int dynrng2e;
/* dynamic range 2 gain */
int dynrng2;
/* coupling strategy exists */
int cplstre;
/* coupling in use */
int cplinu;
/* channel coupled */
unsigned short chincpl[5];
/* if acmod==2 then */
/* Phase flags in use */
int phsflginu;
/* coupling begin frequency code */
int cplbegf;
/* coupling end frequency code */
int cplendf;
/* coupling band structure bits */
unsigned short cplbndstrc[18];
/* Do coupling co-ords exist for this channel? */
unsigned short cplcoe[5];
/* Master coupling co-ordinate */
unsigned short mstrcplco[5];
/* Per coupling band coupling co-ordinates */
unsigned short cplcoexp[5][18];
unsigned short cplcomant[5][18];
/* Phase flags for dual mono */
unsigned short phsflg[18];
/* Is there a rematrixing strategy */
unsigned int rematstr;
/* Rematrixing bits */
unsigned short rematflg[4];
/* Coupling exponent strategy */
int cplexpstr;
/* Exponent strategy for full bandwidth channels */
unsigned short chexpstr[5];
/* Exponent strategy for lfe channel */
int lfeexpstr;
/* Channel bandwidth for independent channels */
unsigned short chbwcod[5];
/* The absolute coupling exponent */
int cplabsexp;
/* Coupling channel exponents (D15 mode gives 18 * 12 /3 encoded exponents */
unsigned short cplexps[18 * 12 / 3];
/* fbw channel exponents */
unsigned short exps[5][252 / 3];
/* channel gain range */
unsigned short gainrng[5];
/* low frequency exponents */
unsigned short lfeexps[3];
/* Bit allocation info */
int baie;
/* Slow decay code */
int sdcycod;
/* Fast decay code */
int fdcycod;
/* Slow gain code */
int sgaincod;
/* dB per bit code */
int dbpbcod;
/* masking floor code */
int floorcod;
/* SNR offset info */
int snroffste;
/* coarse SNR offset */
int csnroffst;
/* coupling fine SNR offset */
int cplfsnroffst;
/* coupling fast gain code */
int cplfgaincod;
/* fbw fine SNR offset */
unsigned short fsnroffst[5];
/* fbw fast gain code */
unsigned short fgaincod[5];
/* lfe fine SNR offset */
int lfefsnroffst;
/* lfe fast gain code */
int lfefgaincod;
/* Coupling leak info */
int cplleake;
/* coupling fast leak initialization */
int cplfleak;
/* coupling slow leak initialization */
int cplsleak;
/* delta bit allocation info */
int deltbaie;
/* coupling delta bit allocation exists */
int cpldeltbae;
/* fbw delta bit allocation exists */
unsigned short deltbae[5];
/* number of cpl delta bit segments */
int cpldeltnseg;
/* coupling delta bit allocation offset */
unsigned short cpldeltoffst[8];
/* coupling delta bit allocation length */
unsigned short cpldeltlen[8];
/* coupling delta bit allocation length */
unsigned short cpldeltba[8];
/* number of delta bit segments */
unsigned short deltnseg[5];
/* fbw delta bit allocation offset */
unsigned short deltoffst[5][8];
/* fbw delta bit allocation length */
unsigned short deltlen[5][8];
/* fbw delta bit allocation length */
unsigned short deltba[5][8];
/* skip length exists */
int skiple;
/* skip length */
int skipl;
/* channel mantissas */
short chmant[5][256];
/* coupling mantissas */
unsigned short cplmant[256];
/* coupling mantissas */
unsigned short lfemant[7];
/* -- Information not in the bitstream, but derived thereof -- */
/* Number of coupling sub-bands */
int ncplsubnd;
/* Number of combined coupling sub-bands
* Derived from ncplsubnd and cplbndstrc */
int ncplbnd;
/* Number of exponent groups by channel
* Derived from strmant, endmant */
int nchgrps[5];
/* Number of coupling exponent groups
* Derived from cplbegf, cplendf, cplexpstr */
int ncplgrps;
/* End mantissa numbers of fbw channels */
unsigned short endmant[5];
/* Start and end mantissa numbers for the coupling channel */
int cplstrtmant;
int cplendmant;
/* Decoded exponent info */
unsigned short fbw_exp[5][256];
unsigned short cpl_exp[256];
unsigned short lfe_exp[7];
/* Bit allocation pointer results */
unsigned short fbw_bap[5][256];
/*FIXME figure out exactly how many entries there should be (253-37?) */
unsigned short cpl_bap[256];
unsigned short lfe_bap[7];
} mpeg3_ac3audblk_t;
/* Bit allocation data */
typedef struct
{
int sdecay;
int fdecay;
int sgain;
int dbknee;
int floor;
short psd[256];
short bndpsd[256];
short excite[256];
short mask[256];
} mpeg3_ac3_bitallocation_t;
/* Mantissa data */
typedef struct
{
unsigned short m_1[3];
unsigned short m_2[3];
unsigned short m_4[2];
unsigned short m_1_pointer;
unsigned short m_2_pointer;
unsigned short m_4_pointer;
} mpeg3_ac3_mantissa_t;
#endif
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