/*  *  bit_allocate.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 <string.h>#include "ac3.h"static inline sint_16 logadd(sint_16 a,sint_16  b);static sint_16 calc_lowcomp(sint_16 a,sint_16 b0,sint_16 b1,sint_16 bin);static inline uint_16 min(sint_16 a,sint_16 b);static inline uint_16 max(sint_16 a,sint_16 b);static void ba_compute_psd(sint_16 start, sint_16 end, sint_16 exps[], 		sint_16 psd[], sint_16 bndpsd[]);static void ba_compute_excitation(sint_16 start, sint_16 end,sint_16 fgain,		sint_16 fastleak, sint_16 slowleak, sint_16 is_lfe, sint_16 bndpsd[],		sint_16 excite[]);static void ba_compute_mask(sint_16 start, sint_16 end, uint_16 fscod,		uint_16 deltbae, uint_16 deltnseg, uint_16 deltoffst[], uint_16 deltba[],		uint_16 deltlen[], sint_16 excite[], sint_16 mask[]);static void ba_compute_bap(sint_16 start, sint_16 end, sint_16 snroffset,		sint_16 psd[], sint_16 mask[], sint_16 bap[]);/* Misc LUTs for bit allocation process */static sint_16 slowdec[]  = { 0x0f,  0x11,  0x13,  0x15  };static sint_16 fastdec[]  = { 0x3f,  0x53,  0x67,  0x7b  };static sint_16 slowgain[] = { 0x540, 0x4d8, 0x478, 0x410 };static sint_16 dbpbtab[]  = { 0x000, 0x700, 0x900, 0xb00 };static uint_16 floortab[] = { 0x2f0, 0x2b0, 0x270, 0x230, 0x1f0, 0x170, 0x0f0, 0xf800 };static sint_16 fastgain[] = { 0x080, 0x100, 0x180, 0x200, 0x280, 0x300, 0x380, 0x400  };static sint_16 bndtab[] = {  0,  1,  2,   3,   4,   5,   6,   7,   8,   9,                      10, 11, 12,  13,  14,  15,  16,  17,  18,  19,                     20, 21, 22,  23,  24,  25,  26,  27,  28,  31,                     34, 37, 40,  43,  46,  49,  55,  61,  67,  73,                     79, 85, 97, 109, 121, 133, 157, 181, 205, 229 };static sint_16 bndsz[]  = { 1,  1,  1,  1,  1,  1,  1,  1,  1,  1,                     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,                     1,  1,  1,  1,  1,  1,  1,  1,  3,  3,                     3,  3,  3,  3,  3,  6,  6,  6,  6,  6,                     6, 12, 12, 12, 12, 24, 24, 24, 24, 24 };static sint_16 masktab[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,                     16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 28, 28, 29,                     29, 29, 30, 30, 30, 31, 31, 31, 32, 32, 32, 33, 33, 33, 34, 34,                     34, 35, 35, 35, 35, 35, 35, 36, 36, 36, 36, 36, 36, 37, 37, 37,                     37, 37, 37, 38, 38, 38, 38, 38, 38, 39, 39, 39, 39, 39, 39, 40,                     40, 40, 40, 40, 40, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41,                     41, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 43, 43, 43,                     43, 43, 43, 43, 43, 43, 43, 43, 43, 44, 44, 44, 44, 44, 44, 44,                     44, 44, 44, 44, 44, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45,                     45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 46, 46, 46,                     46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46,                     46, 46, 46, 46, 46, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47,                     47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 48, 48, 48,                     48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,                     48, 48, 48, 48, 48, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49,                     49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49,  0,  0,  0 };static sint_16 latab[] = { 0x0040, 0x003f, 0x003e, 0x003d, 0x003c, 0x003b, 0x003a, 0x0039,                    0x0038, 0x0037, 0x0036, 0x0035, 0x0034, 0x0034, 0x0033, 0x0032,                    0x0031, 0x0030, 0x002f, 0x002f, 0x002e, 0x002d, 0x002c, 0x002c,                    0x002b, 0x002a, 0x0029, 0x0029, 0x0028, 0x0027, 0x0026, 0x0026,                    0x0025, 0x0024, 0x0024, 0x0023, 0x0023, 0x0022, 0x0021, 0x0021,                    0x0020, 0x0020, 0x001f, 0x001e, 0x001e, 0x001d, 0x001d, 0x001c,                    0x001c, 0x001b, 0x001b, 0x001a, 0x001a, 0x0019, 0x0019, 0x0018,                    0x0018, 0x0017, 0x0017, 0x0016, 0x0016, 0x0015, 0x0015, 0x0015,                    0x0014, 0x0014, 0x0013, 0x0013, 0x0013, 0x0012, 0x0012, 0x0012,                    0x0011, 0x0011, 0x0011, 0x0010, 0x0010, 0x0010, 0x000f, 0x000f,                    0x000f, 0x000e, 0x000e, 0x000e, 0x000d, 0x000d, 0x000d, 0x000d,                    0x000c, 0x000c, 0x000c, 0x000c, 0x000b, 0x000b, 0x000b, 0x000b,                    0x000a, 0x000a, 0x000a, 0x000a, 0x000a, 0x0009, 0x0009, 0x0009,                    0x0009, 0x0009, 0x0008, 0x0008, 0x0008, 0x0008, 0x0008, 0x0008,                    0x0007, 0x0007, 0x0007, 0x0007, 0x0007, 0x0007, 0x0006, 0x0006,                    0x0006, 0x0006, 0x0006, 0x0006, 0x0006, 0x0006, 0x0005, 0x0005,                    0x0005, 0x0005, 0x0005, 0x0005, 0x0005, 0x0005, 0x0004, 0x0004,                    0x0004, 0x0004, 0x0004, 0x0004, 0x0004, 0x0004, 0x0004, 0x0004,                    0x0004, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003,                    0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0002,                    0x0002, 0x0002, 0x0002, 0x0002, 0x0002, 0x0002, 0x0002, 0x0002,                    0x0002, 0x0002, 0x0002, 0x0002, 0x0002, 0x0002, 0x0002, 0x0002,                    0x0002, 0x0002, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001,                    0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001,                    0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001,                    0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001, 0x0001,                    0x0001, 0x0001, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,                    0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,                    0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,                    0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,                    0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,                    0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,                    0x0000, 0x0000, 0x0000, 0x0000};static sint_16 hth[][50] = {{ 0x04d0, 0x04d0, 0x0440, 0x0400, 0x03e0, 0x03c0, 0x03b0, 0x03b0,                        0x03a0, 0x03a0, 0x03a0, 0x03a0, 0x03a0, 0x0390, 0x0390, 0x0390,                        0x0380, 0x0380, 0x0370, 0x0370, 0x0360, 0x0360, 0x0350, 0x0350,                        0x0340, 0x0340, 0x0330, 0x0320, 0x0310, 0x0300, 0x02f0, 0x02f0,                      0x02f0, 0x02f0, 0x0300, 0x0310, 0x0340, 0x0390, 0x03e0, 0x0420,                      0x0460, 0x0490, 0x04a0, 0x0460, 0x0440, 0x0440, 0x0520, 0x0800,                      0x0840, 0x0840 },                                          { 0x04f0, 0x04f0, 0x0460, 0x0410, 0x03e0, 0x03d0, 0x03c0, 0x03b0,                       0x03b0, 0x03a0, 0x03a0, 0x03a0, 0x03a0, 0x03a0, 0x0390, 0x0390,                       0x0390, 0x0380, 0x0380, 0x0380, 0x0370, 0x0370, 0x0360, 0x0360,                       0x0350, 0x0350, 0x0340, 0x0340, 0x0320, 0x0310, 0x0300, 0x02f0,                       0x02f0, 0x02f0, 0x02f0, 0x0300, 0x0320, 0x0350, 0x0390, 0x03e0,                       0x0420, 0x0450, 0x04a0, 0x0490, 0x0460, 0x0440, 0x0480, 0x0630,                       0x0840, 0x0840 },                                          { 0x0580, 0x0580, 0x04b0, 0x0450, 0x0420, 0x03f0, 0x03e0, 0x03d0,                       0x03c0, 0x03b0, 0x03b0, 0x03b0, 0x03a0, 0x03a0, 0x03a0, 0x03a0,                       0x03a0, 0x03a0, 0x03a0, 0x03a0, 0x0390, 0x0390, 0x0390, 0x0390,                       0x0380, 0x0380, 0x0380, 0x0370, 0x0360, 0x0350, 0x0340, 0x0330,                       0x0320, 0x0310, 0x0300, 0x02f0, 0x02f0, 0x02f0, 0x0300, 0x0310,                       0x0330, 0x0350, 0x03c0, 0x0410, 0x0470, 0x04a0, 0x0460, 0x0440,                       0x0450, 0x04e0 }};static sint_16 baptab[] = { 0,  1,  1,  1,  1,  1,  2,  2,  3,  3,  3,  4,  4,  5,  5,  6,                     6,  6,  6,  7,  7,  7,  7,  8,  8,  8,  8,  9,  9,  9,  9, 10,                      10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 13, 13, 14,                     14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15, 15 };static sint_16 sdecay;static sint_16 fdecay;static sint_16 sgain;static sint_16 dbknee;static sint_16 floor;static sint_16 psd[256];static sint_16 bndpsd[256];static sint_16 excite[256];static sint_16 mask[256];static inline uint_16max(sint_16 a,sint_16 b){	return (a > b ? a : b);}	static inline uint_16min(sint_16 a,sint_16 b){	return (a < b ? a : b);}static inline sint_16 logadd(sint_16 a,sint_16  b) { 	sint_16 c;	sint_16 address;	c = a - b; 	address = min((abs(c) >> 1), 255); 		if (c >= 0) 		return(a + latab[address]); 	else 		return(b + latab[address]); }void bit_allocate(uint_16 fscod, bsi_t *bsi, audblk_t *audblk){	uint_16 i;	sint_16 fgain;	sint_16 snroffset;	sint_16 start;	sint_16 end;	sint_16 fastleak;	sint_16 slowleak;	/* Only perform bit_allocation if the exponents have changed or we	 * have new sideband information */	if (audblk->chexpstr[0]  == 0 && audblk->chexpstr[1] == 0 &&			audblk->chexpstr[2]  == 0 && audblk->chexpstr[3] == 0 &&			audblk->chexpstr[4]  == 0 && audblk->cplexpstr   == 0 &&			audblk->lfeexpstr    == 0 && audblk->baie        == 0 &&			audblk->snroffste    == 0 && audblk->deltbaie    == 0)		return;	/* Do some setup before we do the bit alloc */	sdecay = slowdec[audblk->sdcycod]; 	fdecay = fastdec[audblk->fdcycod];	sgain = slowgain[audblk->sgaincod]; 	dbknee = dbpbtab[audblk->dbpbcod]; 	floor = floortab[audblk->floorcod]; 	/* if all the SNR offset constants are zero then the whole block is zero */	if(!audblk->csnroffst    && !audblk->fsnroffst[0] && 		 !audblk->fsnroffst[1] && !audblk->fsnroffst[2] && 		 !audblk->fsnroffst[3] && !audblk->fsnroffst[4] &&		 !audblk->cplfsnroffst && !audblk->lfefsnroffst)	{		memset(audblk->fbw_bap,0,sizeof(uint_16) * 256 * 5);		memset(audblk->cpl_bap,0,sizeof(uint_16) * 256);		memset(audblk->lfe_bap,0,sizeof(uint_16) * 7);		return;	}		 	for(i = 0; i < bsi->nfchans; i++)	{		start = 0;		end = audblk->endmant[i] ; 		fgain = fastgain[audblk->fgaincod[i]]; 		snroffset = (((audblk->csnroffst - 15) << 4) + audblk->fsnroffst[i]) << 2 ;		fastleak = 0;		slowleak = 0;		ba_compute_psd(start, end, (short int *)audblk->fbw_exp[i], psd, bndpsd);		ba_compute_excitation(start, end , fgain, fastleak, slowleak, 0, bndpsd, excite);		ba_compute_mask(start, end, fscod, audblk->deltbae[i], audblk->deltnseg[i], 				audblk->deltoffst[i], audblk->deltba[i], audblk->deltlen[i], excite, mask);		ba_compute_bap(start, end, snroffset, psd, mask, (short int *)audblk->fbw_bap[i]);	}	if(audblk->cplinu)	{