ac3_equ.h

关于DVD的MPEG2用的DSP代码,在DSP的实现MPEG的压缩,解压算法.

#define	REVISION	8		/* bsid revision number */
#define	AC3I_REV	0x0300		/* AC-3 info revision */
#define	CRC_REV		0x0300		/* CRC calculator revision */
#define	AC3D_REV	0x0309		/* AC-3 decoder revision */

/**** General system equates ****/
#define	NCHANS		6		/* max # channels */
#define	NFCHANS		5		/* max # full bw channels */
#define	NPCMCHANS	6		/* max # output channels */
#define NKVARS          6               /*# of karaoke pan and mix param*/
/**** Filter bank equates ****/
#define	N		256		/* block size */
#define	FFTN		(N/2)		/* FFT transform size */
#define	FFTNLG2M3	4		/* log2(FFTN) - 3 */
#define	NMANTS		253		/* max # mantissas per channel */
#define	NLFEMANTS	7		/* # lfe mantissas */

/**** Exponent, mantissa equates ****/
#define	MAXEXP		32		/* max decoder exponent */
	
/**** Coupling equates ****/
#define	CPLBNDSZ	12		/* coupling band size */
#define	NCPLBNDS	18		/* max # coupling bands */

/**** Bit allocation equates ****/
#define	LATABSZ 	256		/* log adder table size */
#define	PVTABSZ		64		/* bit alloc pointer table size */
#define	NBABNDS		50		/* max # bit allocation bands */
#define	NLFEBABNDS	NLFEMANTS	/* # lfe bit allocation bands */
#define	NDELTS		8		/* max # delta bit alloc segments */
#define	BANDBUFSZ	24		/* max bit alloc band size */

/**** Random number generator equates ****/
#define	DITHSEED	1		/* random number generator seed */
#define	DITHMULT	47989		/* linear congruential multiplier */
#define	DITHSCALE	0.707106781	/* dither scale factor */

/**** Miscellaneous equates ****/
#define	SYNC_WD		0x0b77		/* AC-3 frame sync word */
#define	NFSCOD		3		/* # defined sample rates */
#define	NDATARATE	38		/* # defined data rates */
#define	NACMOD		8		/* # audio coding modes */
#define	NREMATBNDS	4		/* max # rematrixing bands */

#define	UNITY		1.0
#define	M3DB		0.707106781
#define	M6DB		0.5
	/* exponent strategy */
#define REUSE		0
#define  D15		1
#define  D25		2
#define  D45		3
	/* audio coding mode */
#define MODE11		0
#define MODE10		1
#define MODE20		2
#define MODE30		3
#define	MODE21		4
#define MODE31		5
#define MODE22		6
#define MODE32		7
	/* dual mono downmix mode */
#define	DUAL_STEREO	0
#define	DUAL_LEFTMONO	1
#define	DUAL_RGHTMONO	2
#define	DUAL_MIXMONO	3
	/* compression mode */
#define	COMP_CUSTOM_A	0
#define	COMP_CUSTOM_D	1	
#define	COMP_LINE	2
#define	 COMP_RF	3
	/* delta bit allocation strategy */
#define	DELTREUSE	0
#define DELTNEW		1
#define DELTSTOP	2

/**** Karaoke Mode Equate ****/
#define	KMODE		7
#define	RADFACT		1.57079633
#define	RADFACTD2	(RADFACT / 2)


/**** AC-3 channel ordering equates ****/

#define	LEFT			0	/* left channel */
#define	CNTR			1	/* center channel */
#define	RGHT			2	/* right channel */
#define	LSUR			3	/* left surround channel */
#define	RSUR			4	/* right surround channel */
#define	LFE			5	/* low frequency effects channel */
#define	MSUR			3	/* mono surround channel */
#define	NONE			-1	/* channel not in use */

// should be in usr_equ
#define	NBLOCKS			6