/*  *    parse.c * *	Copyright (C) Aaron Holtzman - May 1999 * *  This file is part of ac3dec, a free Dolby AC-3 stream decoder. *	 *  ac3dec 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, or (at your option) *  any later version. *    *  ac3dec 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 GNU Make; see the file COPYING.  If not, write to *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  * * */#include <stdlib.h>#include <stdio.h>#include "ac3.h"#include "decode.h"#include "bitstream.h"#include "stats.h"#include "debug.h"#include "parse.h"/* Misc LUT */static	uint_16 nfchans[] = {2,1,2,3,3,4,4,5};struct frmsize_s{	uint_16 bit_rate;	uint_16 frm_size[3];};struct frmsize_s frmsizecod_tbl[] = {      { 32  ,{64   ,69   ,96   } },      { 32  ,{64   ,70   ,96   } },      { 40  ,{80   ,87   ,120  } },      { 40  ,{80   ,88   ,120  } },      { 48  ,{96   ,104  ,144  } },      { 48  ,{96   ,105  ,144  } },      { 56  ,{112  ,121  ,168  } },      { 56  ,{112  ,122  ,168  } },      { 64  ,{128  ,139  ,192  } },      { 64  ,{128  ,140  ,192  } },      { 80  ,{160  ,174  ,240  } },      { 80  ,{160  ,175  ,240  } },      { 96  ,{192  ,208  ,288  } },      { 96  ,{192  ,209  ,288  } },      { 112 ,{224  ,243  ,336  } },      { 112 ,{224  ,244  ,336  } },      { 128 ,{256  ,278  ,384  } },      { 128 ,{256  ,279  ,384  } },      { 160 ,{320  ,348  ,480  } },      { 160 ,{320  ,349  ,480  } },      { 192 ,{384  ,417  ,576  } },      { 192 ,{384  ,418  ,576  } },      { 224 ,{448  ,487  ,672  } },      { 224 ,{448  ,488  ,672  } },      { 256 ,{512  ,557  ,768  } },      { 256 ,{512  ,558  ,768  } },      { 320 ,{640  ,696  ,960  } },      { 320 ,{640  ,697  ,960  } },      { 384 ,{768  ,835  ,1152 } },      { 384 ,{768  ,836  ,1152 } },      { 448 ,{896  ,975  ,1344 } },      { 448 ,{896  ,976  ,1344 } },      { 512 ,{1024 ,1114 ,1536 } },      { 512 ,{1024 ,1115 ,1536 } },      { 576 ,{1152 ,1253 ,1728 } },      { 576 ,{1152 ,1254 ,1728 } },      { 640 ,{1280 ,1393 ,1920 } },      { 640 ,{1280 ,1394 ,1920 } }};/* Parse a syncinfo structure, minus the sync word */voidparse_syncinfo(syncinfo_t *syncinfo,bitstream_t *bs){#ifdef DO_NIST        inputstream->read_frame(3);#endif	/* Get crc1 - we don't actually use this data though */	bitstream_get(bs,16);	/* Get the sampling rate */	syncinfo->fscod  = bitstream_get(bs,2);	/* Get the frame size code */	syncinfo->frmsizecod = bitstream_get(bs,6);	syncinfo->bit_rate = frmsizecod_tbl[syncinfo->frmsizecod].bit_rate;	syncinfo->frame_size = frmsizecod_tbl[syncinfo->frmsizecod].frm_size[syncinfo->fscod];#ifdef DO_NIST        inputstream->read_frame(syncinfo->frame_size*2-5);#endif	stats_printf_syncinfo(syncinfo);}/* * This routine fills a bsi struct from the AC3 stream */voidparse_bsi(bsi_t *bsi,bitstream_t *bs){	uint_32 i;	/* Check the AC-3 version number */	bsi->bsid = bitstream_get(bs,5);	/* Get the audio service provided by the steram */	bsi->bsmod = bitstream_get(bs,3);	/* Get the audio coding mode (ie how many channels)*/	bsi->acmod = bitstream_get(bs,3);	/* Predecode the number of full bandwidth channels as we use this	 * number a lot */	bsi->nfchans = nfchans[bsi->acmod];	/* If it is in use, get the centre channel mix level */	if ((bsi->acmod & 0x1) && (bsi->acmod != 0x1))		bsi->cmixlev = bitstream_get(bs,2);	/* If it is in use, get the surround channel mix level */	if (bsi->acmod & 0x4)		bsi->surmixlev = bitstream_get(bs,2);	/* Get the dolby surround mode if in 2/0 mode */	if(bsi->acmod == 0x2)		bsi->dsurmod= bitstream_get(bs,2);	/* Is the low frequency effects channel on? */	bsi->lfeon = bitstream_get(bs,1);	/* Get the dialogue normalization level */	bsi->dialnorm = bitstream_get(bs,5);	/* Does compression gain exist? */	bsi->compre = bitstream_get(bs,1);	if (bsi->compre)	{		/* Get compression gain */		bsi->compr = bitstream_get(bs,8);	}	/* Does language code exist? */	bsi->langcode = bitstream_get(bs,1);	if (bsi->langcode)	{		/* Get langauge code */		bsi->langcod = bitstream_get(bs,8);	}	/* Does audio production info exist? */	bsi->audprodie = bitstream_get(bs,1);	if (bsi->audprodie)	{		/* Get mix level */		bsi->mixlevel = bitstream_get(bs,5);		/* Get room type */		bsi->roomtyp = bitstream_get(bs,2);	}	/* If we're in dual mono mode then get some extra info */	if (bsi->acmod ==0)	{		/* Get the dialogue normalization level two */		bsi->dialnorm2 = bitstream_get(bs,5);		/* Does compression gain two exist? */		bsi->compr2e = bitstream_get(bs,1);		if (bsi->compr2e)		{			/* Get compression gain two */			bsi->compr2 = bitstream_get(bs,8);		}		/* Does language code two exist? */		bsi->langcod2e = bitstream_get(bs,1);		if (bsi->langcod2e)		{			/* Get langauge code two */			bsi->langcod2 = bitstream_get(bs,8);		}		/* Does audio production info two exist? */		bsi->audprodi2e = bitstream_get(bs,1);		if (bsi->audprodi2e)		{			/* Get mix level two */			bsi->mixlevel2 = bitstream_get(bs,5);			/* Get room type two */			bsi->roomtyp2 = bitstream_get(bs,2);		}	}	/* Get the copyright bit */	bsi->copyrightb = bitstream_get(bs,1);	/* Get the original bit */	bsi->origbs = bitstream_get(bs,1);		/* Does timecode one exist? */	bsi->timecod1e = bitstream_get(bs,1);	if(bsi->timecod1e)		bsi->timecod1 = bitstream_get(bs,14);	/* Does timecode two exist? */	bsi->timecod2e = bitstream_get(bs,1);	if(bsi->timecod2e)		bsi->timecod2 = bitstream_get(bs,14);	/* Does addition info exist? */	bsi->addbsie = bitstream_get(bs,1);	if(bsi->addbsie)	{		/* Get how much info is there */		bsi->addbsil = bitstream_get(bs,6);		/* Get the additional info */		for(i=0;i<(bsi->addbsil + 1);i++)			bsi->addbsi[i] = bitstream_get(bs,8);	}	stats_printf_bsi(bsi);}/* More pain inducing parsing */voidparse_audblk(bsi_t *bsi,audblk_t *audblk,bitstream_t *bs){	int i,j;	for (i=0;i < bsi->nfchans; i++)	{		/* Is this channel an interleaved 256 + 256 block ? */		audblk->blksw[i] = bitstream_get(bs,1);	}	for (i=0;i < bsi->nfchans; i++)	{		/* Should we dither this channel? */		audblk->dithflag[i] = bitstream_get(bs,1);	}	/* Does dynamic range control exist? */	audblk->dynrnge = bitstream_get(bs,1);	if (audblk->dynrnge)	{		/* Get dynamic range info */		audblk->dynrng = bitstream_get(bs,8);	}	/* If we're in dual mono mode then get the second channel DR info */	if (bsi->acmod == 0)	{		/* Does dynamic range control two exist? */		audblk->dynrng2e = bitstream_get(bs,1);		if (audblk->dynrng2e)		{			/* Get dynamic range info */			audblk->dynrng2 = bitstream_get(bs,8);		}	}	/* Does coupling strategy exist? */	audblk->cplstre = bitstream_get(bs,1);	if (audblk->cplstre)	{		/* Is coupling turned on? */		audblk->cplinu = bitstream_get(bs,1);		if(audblk->cplinu)		{			for(i=0;i < bsi->nfchans; i++)				audblk->chincpl[i] = bitstream_get(bs,1);			if(bsi->acmod == 0x2)				audblk->phsflginu = bitstream_get(bs,1);			audblk->cplbegf = bitstream_get(bs,4);			audblk->cplendf = bitstream_get(bs,4);			audblk->ncplsubnd = (audblk->cplendf + 2) - audblk->cplbegf + 1;			/* Calculate the start and end bins of the coupling channel */			audblk->cplstrtmant = (audblk->cplbegf * 12) + 37 ; 			audblk->cplendmant =  ((audblk->cplendf + 3) * 12) + 37;			/* The number of combined subbands is ncplsubnd minus each combined			 * band */			audblk->ncplbnd = audblk->ncplsubnd; 			for(i=1; i< audblk->ncplsubnd; i++)			{				audblk->cplbndstrc[i] = bitstream_get(bs,1);				audblk->ncplbnd -= audblk->cplbndstrc[i];			}		}	}	if(audblk->cplinu)	{		/* Loop through all the channels and get their coupling co-ords */			for(i=0;i < bsi->nfchans;i++)		{			if(!audblk->chincpl[i])				continue;			/* Is there new coupling co-ordinate info? */			audblk->cplcoe[i] = bitstream_get(bs,1);			if(audblk->cplcoe[i])			{				audblk->mstrcplco[i] = bitstream_get(bs,2); 				for(j=0;j < audblk->ncplbnd; j++)				{					audblk->cplcoexp[i][j] = bitstream_get(bs,4); 					audblk->cplcomant[i][j] = bitstream_get(bs,4); 				}			}		}		/* If we're in dual mono mode, there's going to be some phase info */		if( (bsi->acmod == 0x2) && audblk->phsflginu && 				(audblk->cplcoe[0] || audblk->cplcoe[1]))		{			for(j=0;j < audblk->ncplbnd; j++)				audblk->phsflg[j] = bitstream_get(bs,1); 		}	}	/* If we're in dual mono mode, there may be a rematrix strategy */	if(bsi->acmod == 0x2)	{		audblk->rematstr = bitstream_get(bs,1);		if(audblk->rematstr)		{			if (audblk->cplinu == 0) 			{ 				for(i = 0; i < 4; i++) 					audblk->rematflg[i] = bitstream_get(bs,1);			}			if((audblk->cplbegf > 2) && audblk->cplinu) 			{				for(i = 0; i < 4; i++) 					audblk->rematflg[i] = bitstream_get(bs,1);			}			if((audblk->cplbegf <= 2) && audblk->cplinu) 			{ 				for(i = 0; i < 3; i++) 					audblk->rematflg[i] = bitstream_get(bs,1);			} 			if((audblk->cplbegf == 0) && audblk->cplinu) 				for(i = 0; i < 2; i++) 					audblk->rematflg[i] = bitstream_get(bs,1);		}	}	if (audblk->cplinu)	{		/* Get the coupling channel exponent strategy */		audblk->cplexpstr = bitstream_get(bs,2);		audblk->ncplgrps = (audblk->cplendmant - audblk->cplstrtmant) / 				(3 << (audblk->cplexpstr-1));	}	for(i = 0; i < bsi->nfchans; i++)		audblk->chexpstr[i] = bitstream_get(bs,2);	/* Get the exponent strategy for lfe channel */	if(bsi->lfeon) 		audblk->lfeexpstr = bitstream_get(bs,1);	/* Determine the bandwidths of all the fbw channels */	for(i = 0; i < bsi->nfchans; i++) 	{ 		uint_16 grp_size;		if(audblk->chexpstr[i] != EXP_REUSE) 		{ 			if (audblk->cplinu && audblk->chincpl[i]) 			{				audblk->endmant[i] = audblk->cplstrtmant;			}			else			{				audblk->chbwcod[i] = bitstream_get(bs,6); 				audblk->endmant[i] = ((audblk->chbwcod[i] + 12) * 3) + 37;			}			/* Calculate the number of exponent groups to fetch */			grp_size =  3 * (1 << (audblk->chexpstr[i] - 1));			audblk->nchgrps[i] = (audblk->endmant[i] - 1 + (grp_size - 3)) / grp_size;		}	}	/* Get the coupling exponents if they exist */	if(audblk->cplinu && (audblk->cplexpstr != EXP_REUSE))	{		audblk->cplabsexp = bitstream_get(bs,4);		for(i=0;i< audblk->ncplgrps;i++)			audblk->cplexps[i] = bitstream_get(bs,7);	}	/* Get the fwb channel exponents */	for(i=0;i < bsi->nfchans; i++)	{		if(audblk->chexpstr[i] != EXP_REUSE)		{			audblk->exps[i][0] = bitstream_get(bs,4);						for(j=1;j<=audblk->nchgrps[i];j++)				audblk->exps[i][j] = bitstream_get(bs,7);			audblk->gainrng[i] = bitstream_get(bs,2);		}	}	/* Get the lfe channel exponents */	if(bsi->lfeon && (audblk->lfeexpstr != EXP_REUSE))	{		audblk->lfeexps[0] = bitstream_get(bs,4);		audblk->lfeexps[1] = bitstream_get(bs,7);		audblk->lfeexps[2] = bitstream_get(bs,7);	}	/* Get the parametric bit allocation parameters */	audblk->baie = bitstream_get(bs,1);	if(audblk->baie)	{		audblk->sdcycod = bitstream_get(bs,2);		audblk->fdcycod = bitstream_get(bs,2);		audblk->sgaincod = bitstream_get(bs,2);		audblk->dbpbcod = bitstream_get(bs,2);		audblk->floorcod = bitstream_get(bs,3);	}	/* Get the SNR off set info if it exists */	audblk->snroffste = bitstream_get(bs,1);	if(audblk->snroffste)	{		audblk->csnroffst = bitstream_get(bs,6);		if(audblk->cplinu)		{			audblk->cplfsnroffst = bitstream_get(bs,4);			audblk->cplfgaincod = bitstream_get(bs,3);		}		for(i = 0;i < bsi->nfchans; i++)		{			audblk->fsnroffst[i] = bitstream_get(bs,4);			audblk->fgaincod[i] = bitstream_get(bs,3);		}		if(bsi->lfeon)		{			audblk->lfefsnroffst = bitstream_get(bs,4);			audblk->lfefgaincod = bitstream_get(bs,3);		}	}	/* Get coupling leakage info if it exists */	if(audblk->cplinu)	{		audblk->cplleake = bitstream_get(bs,1);					if(audblk->cplleake)		{			audblk->cplfleak = bitstream_get(bs,3);			audblk->cplsleak = bitstream_get(bs,3);		}	}		/* Get the delta bit alloaction info */	audblk->deltbaie = bitstream_get(bs,1);			if(audblk->deltbaie)	{		if(audblk->cplinu)			audblk->cpldeltbae = bitstream_get(bs,2);		for(i = 0;i < bsi->nfchans; i++)			audblk->deltbae[i] = bitstream_get(bs,2);		if (audblk->cplinu && (audblk->cpldeltbae == DELTA_BIT_NEW))		{			audblk->cpldeltnseg = bitstream_get(bs,3);			for(i = 0;i < audblk->cpldeltnseg + 1; i++)			{				audblk->cpldeltoffst[i] = bitstream_get(bs,5);				audblk->cpldeltlen[i] = bitstream_get(bs,4);				audblk->cpldeltba[i] = bitstream_get(bs,3);			}		}		for(i = 0;i < bsi->nfchans; i++)		{			if (audblk->deltbae[i] == DELTA_BIT_NEW)			{				audblk->deltnseg[i] = bitstream_get(bs,3);				for(j = 0; j < audblk->deltnseg[i] + 1; j++)				{					audblk->deltoffst[i][j] = bitstream_get(bs,5);					audblk->deltlen[i][j] = bitstream_get(bs,4);					audblk->deltba[i][j] = bitstream_get(bs,3);				}			}		}	}	/* Check to see if there's any dummy info to get */	if((audblk->skiple =  bitstream_get(bs,1)))	{		uint_16 skip_data;		audblk->skipl = bitstream_get(bs,9);		//XXX remove		//fprintf(stderr,"(parse) skipping %d bytes\n",audblk->skipl);		for(i = 0; i < audblk->skipl ; i++)		{			skip_data = bitstream_get(bs,8);			//XXX remove			//fprintf(stderr,"skipped data %2x\n",skip_data);			//if(skip_data != 0)			//{					//dprintf("(parse) Invalid skipped data %2x\n",skip_data);				//exit(1);			//}		}	}	stats_printf_audblk(audblk);}voidparse_auxdata(syncinfo_t *syncinfo,bitstream_t *bs){	int i;	int skip_length;	uint_16 crc;	uint_16 auxdatae;	skip_length = (syncinfo->frame_size * 16)  - bs->total_bits_read - 17 - 1;	//XXX remove	//dprintf("(auxdata) skipping %d auxbits\n",skip_length);		for(i=0; i <  skip_length; i++)		//printf("Skipped bit %i\n",(uint_16)bitstream_get(bs,1));		bitstream_get(bs,1);	//get the auxdata exists bit	auxdatae = bitstream_get(bs,1);		//XXX remove	//dprintf("auxdatae = %i\n",auxdatae);	//Skip the CRC reserved bit	bitstream_get(bs,1);	//Get the crc	crc = bitstream_get(bs,16);}