Xash3D FWGS engine.
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/*
layer3.c - compact version of famous library mpg123
Copyright (C) 2017 Uncle Mike
This program 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 3 of the License, or
(at your option) any later version.
This program 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.
*/
#include "mpg123.h"
#include "huffman.h"
#include "getbits.h"
#include <math.h>
// static one-time calculated tables... or so
float COS6_1; // dct12 wants to use that
float COS6_2; // dct12 wants to use that
float cos9[3]; // dct36 wants to use that
float cos18[3]; // dct36 wants to use that
float tfcos12[3]; // dct12 wants to use that
float tfcos36[9]; // dct36 wants to use that
static float ispow[8207];
static float COS9[9];
static float aa_ca[8];
static float aa_cs[8];
static float win[4][36];
static float win1[4][36];
static float tan1_1[16];
static float tan2_1[16];
static float tan1_2[16];
static float tan2_2[16];
static float pow1_1[2][16];
static float pow2_1[2][16];
static float pow1_2[2][16];
static float pow2_2[2][16];
static int mapbuf0[9][152];
static int mapbuf1[9][156];
static int mapbuf2[9][44];
static int *map[9][3];
static int *mapend[9][3];
static uint n_slen2[512]; // MPEG 2.0 slen for 'normal' mode
static uint i_slen2[256]; // MPEG 2.0 slen for intensity stereo
// Decoder state data, living on the stack of do_layer3.
typedef struct gr_info_s
{
int scfsi;
uint part2_3_length;
uint big_values;
uint scalefac_compress;
uint block_type;
uint mixed_block_flag;
uint table_select[3];
// making those two signed int as workaround for open64/pathscale/sun compilers,
// and also for consistency, since they're worked on together with other signed variables.
int maxband[3];
int maxbandl;
uint maxb;
uint region1start;
uint region2start;
uint preflag;
uint scalefac_scale;
uint count1table_select;
float *full_gain[3];
float *pow2gain;
} gr_info_t;
typedef struct
{
uint main_data_begin;
uint private_bits;
// hm, funny... struct inside struct...
struct
{
gr_info_t gr[2];
} ch[2];
} III_sideinfo;
typedef struct
{
word longIdx[23];
byte longDiff[22];
word shortIdx[14];
byte shortDiff[13];
} bandInfoStruct;
// techy details about our friendly MPEG data. Fairly constant over the years ;-)
static const bandInfoStruct bandInfo[9] =
{
{ // MPEG 1.0
{0,4,8,12,16,20,24,30,36,44,52,62,74, 90,110,134,162,196,238,288,342,418,576},
{4,4,4,4,4,4,6,6,8, 8,10,12,16,20,24,28,34,42,50,54, 76,158},
{0,4*3,8*3,12*3,16*3,22*3,30*3,40*3,52*3,66*3, 84*3,106*3,136*3,192*3},
{4,4,4,4,6,8,10,12,14,18,22,30,56}
},
{
{0,4,8,12,16,20,24,30,36,42,50,60,72, 88,106,128,156,190,230,276,330,384,576},
{4,4,4,4,4,4,6,6,6, 8,10,12,16,18,22,28,34,40,46,54, 54,192},
{0,4*3,8*3,12*3,16*3,22*3,28*3,38*3,50*3,64*3, 80*3,100*3,126*3,192*3},
{4,4,4,4,6,6,10,12,14,16,20,26,66}
},
{
{0,4,8,12,16,20,24,30,36,44,54,66,82,102,126,156,194,240,296,364,448,550,576},
{4,4,4,4,4,4,6,6,8,10,12,16,20,24,30,38,46,56,68,84,102, 26},
{0,4*3,8*3,12*3,16*3,22*3,30*3,42*3,58*3,78*3,104*3,138*3,180*3,192*3},
{4,4,4,4,6,8,12,16,20,26,34,42,12}
},
{ // MPEG 2.0
{0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
{6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54 } ,
{0,4*3,8*3,12*3,18*3,24*3,32*3,42*3,56*3,74*3,100*3,132*3,174*3,192*3} ,
{4,4,4,6,6,8,10,14,18,26,32,42,18 }
},
{ // twiddling 3 values here (not just 330->332!) fixed bug 1895025.
{0,6,12,18,24,30,36,44,54,66,80,96,114,136,162,194,232,278,332,394,464,540,576},
{6,6,6,6,6,6,8,10,12,14,16,18,22,26,32,38,46,54,62,70,76,36 },
{0,4*3,8*3,12*3,18*3,26*3,36*3,48*3,62*3,80*3,104*3,136*3,180*3,192*3},
{4,4,4,6,8,10,12,14,18,24,32,44,12 }
},
{
{0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
{6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54 },
{0,4*3,8*3,12*3,18*3,26*3,36*3,48*3,62*3,80*3,104*3,134*3,174*3,192*3},
{4,4,4,6,8,10,12,14,18,24,30,40,18 }
},
{ // MPEG 2.5
{0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
{6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54},
{0,12,24,36,54,78,108,144,186,240,312,402,522,576},
{4,4,4,6,8,10,12,14,18,24,30,40,18}
},
{
{0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
{6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54},
{0,12,24,36,54,78,108,144,186,240,312,402,522,576},
{4,4,4,6,8,10,12,14,18,24,30,40,18}
},
{
{0,12,24,36,48,60,72,88,108,132,160,192,232,280,336,400,476,566,568,570,572,574,576},
{12,12,12,12,12,12,16,20,24,28,32,40,48,56,64,76,90,2,2,2,2,2},
{0, 24, 48, 72,108,156,216,288,372,480,486,492,498,576},
{8,8,8,12,16,20,24,28,36,2,2,2,26}
}
};
static byte pretab_choice[2][22] =
{
{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,2,2,3,3,3,2,0}
};
// init tables for layer-3 ... specific with the downsampling...
void init_layer3( void )
{
int i, j, k, l;
for( i = 0; i < 8207; i++ )
ispow[i] = DOUBLE_TO_REAL_POW43( pow( (double)i, (double)4.0 / 3.0 ));
for( i = 0; i < 8; i++ )
{
const double Ci[8] = { -0.6, -0.535, -0.33, -0.185, -0.095, -0.041, -0.0142, -0.0037 };
double sq = sqrt( 1.0 + Ci[i] * Ci[i] );
aa_cs[i] = DOUBLE_TO_REAL( 1.0 / sq );
aa_ca[i] = DOUBLE_TO_REAL( Ci[i] / sq );
}
for( i = 0; i < 18; i++ )
{
win[0][i] = win[1][i] = DOUBLE_TO_REAL( 0.5 * sin( M_PI / 72.0 * (double)(2 * (i + 0) + 1)) / cos( M_PI * (double)(2 * (i + 0) + 19) / 72.0) );
win[0][i+18] = win[3][i+18] = DOUBLE_TO_REAL( 0.5 * sin( M_PI/72.0 * (double)(2 * (i + 18) + 1)) / cos( M_PI * (double)(2 * (i + 18) + 19) / 72.0) );
}
for( i = 0; i < 6; i++ )
{
win[1][i+18] = DOUBLE_TO_REAL( 0.5 / cos ( M_PI * (double)(2 * (i + 18) + 19) / 72.0 ));
win[3][i+12] = DOUBLE_TO_REAL( 0.5 / cos ( M_PI * (double)(2 * (i + 12) + 19) / 72.0 ));
win[1][i+24] = DOUBLE_TO_REAL( 0.5 * sin( M_PI / 24.0 * (double)(2 * i + 13)) / cos( M_PI * (double)(2 * (i + 24) + 19) / 72.0 ));
win[1][i+30] = win[3][i] = DOUBLE_TO_REAL( 0.0 );
win[3][i+6 ] = DOUBLE_TO_REAL( 0.5 * sin( M_PI / 24.0 * (double)(2 * i + 1)) / cos( M_PI * (double)(2 * (i + 6 ) + 19) / 72.0 ));
}
for( i = 0; i < 9; i++ )
COS9[i] = DOUBLE_TO_REAL( cos( M_PI / 18.0 * (double)i ));
for( i = 0; i < 9; i++ )
tfcos36[i] = DOUBLE_TO_REAL( 0.5 / cos( M_PI * (double)(i * 2 + 1) / 36.0 ));
for( i = 0; i < 3; i++ )
tfcos12[i] = DOUBLE_TO_REAL( 0.5 / cos( M_PI * (double)(i * 2 + 1) / 12.0 ));
COS6_1 = DOUBLE_TO_REAL( cos( M_PI / 6.0 * (double)1 ));
COS6_2 = DOUBLE_TO_REAL( cos( M_PI / 6.0 * (double)2 ));
cos9[0] = DOUBLE_TO_REAL( cos( 1.0 * M_PI / 9.0));
cos9[1] = DOUBLE_TO_REAL( cos( 5.0 * M_PI / 9.0));
cos9[2] = DOUBLE_TO_REAL( cos( 7.0 * M_PI / 9.0));
cos18[0] = DOUBLE_TO_REAL( cos( 1.0 * M_PI / 18.0));
cos18[1] = DOUBLE_TO_REAL( cos( 11.0 * M_PI / 18.0));
cos18[2] = DOUBLE_TO_REAL( cos( 13.0 * M_PI / 18.0));
for( i = 0; i < 12; i++ )
win[2][i] = DOUBLE_TO_REAL( 0.5 * sin( M_PI / 24.0 * (double)(2 * i + 1) ) / cos( M_PI * (double)(2 * i + 7) / 24.0 ));
for( i = 0; i < 16; i++ )
{
double t = tan((double)i * M_PI / 12.0 );
tan1_1[i] = DOUBLE_TO_REAL_15( t / (1.0 + t));
tan2_1[i] = DOUBLE_TO_REAL_15( 1.0 / (1.0 + t));
tan1_2[i] = DOUBLE_TO_REAL_15( M_SQRT2 * t / (1.0 + t));
tan2_2[i] = DOUBLE_TO_REAL_15( M_SQRT2 / (1.0 + t));
for( j = 0; j < 2; j++ )
{
double base = pow( 2.0, -0.25 * (j + 1.0));
double p1 = 1.0, p2 = 1.0;
if( i > 0 )
{
if( i & 1 ) p1 = pow( base,(i + 1.0) * 0.5);
else p2 = pow( base, i * 0.5 );
}
pow1_1[j][i] = DOUBLE_TO_REAL_15( p1 );
pow2_1[j][i] = DOUBLE_TO_REAL_15( p2 );
pow1_2[j][i] = DOUBLE_TO_REAL_15( M_SQRT2 * p1 );
pow2_2[j][i] = DOUBLE_TO_REAL_15( M_SQRT2 * p2 );
}
}
for( j = 0; j < 4; j++ )
{
const int len[4] = { 36, 36, 12, 36 };
for( i = 0; i < len[j]; i += 2 )
win1[j][i] = +win[j][i];
for( i = 1; i < len[j]; i += 2 )
win1[j][i] = -win[j][i];
}
for( j = 0; j < 9; j++ )
{
const bandInfoStruct *bi = &bandInfo[j];
int cb, lwin;
const byte *bdf;
int *mp;
mp = map[j][0] = mapbuf0[j];
bdf = bi->longDiff;
for( i = 0, cb = 0; cb < 8 ; cb++, i += *bdf++ )
{
*mp++ = (*bdf) >> 1;
*mp++ = i;
*mp++ = 3;
*mp++ = cb;
}
bdf = bi->shortDiff + 3;
for( cb = 3;cb < 13; cb++ )
{
int l = (*bdf++) >> 1;
for( lwin = 0; lwin < 3; lwin++ )
{
*mp++ = l;
*mp++ = i + lwin;
*mp++ = lwin;
*mp++ = cb;
}
i += 6 * l;
}
mapend[j][0] = mp;
mp = map[j][1] = mapbuf1[j];
bdf = bi->shortDiff + 0;
for( i = 0, cb = 0; cb < 13; cb++ )
{
int l = (*bdf++) >> 1;
for( lwin = 0; lwin < 3; lwin++ )
{
*mp++ = l;
*mp++ = i + lwin;
*mp++ = lwin;
*mp++ = cb;
}
i += 6 * l;
}
mapend[j][1] = mp;
mp = map[j][2] = mapbuf2[j];
bdf = bi->longDiff;
for( cb = 0; cb < 22; cb++ )
{
*mp++ = (*bdf++) >> 1;
*mp++ = cb;
}
mapend[j][2] = mp;
}
// now for some serious loopings!
for( i = 0; i < 5; i++ )
{
for( j = 0; j < 6; j++ )
{
for( k = 0; k < 6; k++ )
{
int n = k + j * 6 + i * 36;
i_slen2[n] = i|(j<<3)|(k<<6)|(3<<12);
}
}
}
for( i = 0; i < 4; i++ )
{
for( j = 0; j < 4; j++ )
{
for( k = 0; k < 4; k++ )
{
int n = k + j * 4 + i * 16;
i_slen2[n+180] = i|(j<<3)|(k<<6)|(4<<12);
}
}
}
for( i = 0; i < 4; i++ )
{
for( j = 0; j < 3; j++ )
{
int n = j + i * 3;
i_slen2[n+244] = i|(j<<3) | (5<<12);
n_slen2[n+500] = i|(j<<3) | (2<<12) | (1<<15);
}
}
for( i = 0; i < 5; i++ )
{
for( j = 0; j < 5; j++ )
{
for( k = 0; k < 4; k++ )
{
for( l = 0; l < 4; l++ )
{
int n = l + k * 4 + j * 16 + i * 80;
n_slen2[n] = i|(j<<3)|(k<<6)|(l<<9)|(0<<12);
}
}
}
}
for( i = 0; i < 5; i++ )
{
for( j = 0; j < 5; j++ )
{
for( k = 0; k < 4; k++ )
{
int n = k + j * 4 + i * 20;
n_slen2[n+400] = i|(j<<3)|(k<<6)|(1<<12);
}
}
}
}
void init_layer3_stuff( mpg123_handle_t *fr )
{
int i,j;
for( i = -256; i < 118 + 4; i++ )
fr->gainpow2[i+256] = DOUBLE_TO_REAL_SCALE_LAYER3( pow((double)2.0, -0.25 * (double)(i + 210)), i + 256 );
for( j = 0; j < 9; j++ )
{
for( i = 0; i < 23; i++ )
{
fr->longLimit[j][i] = (bandInfo[j].longIdx[i] - 1 + 8) / 18 + 1;
if( fr->longLimit[j][i] > fr->down_sample_sblimit )
fr->longLimit[j][i] = fr->down_sample_sblimit;
}
for( i = 0; i < 14; i++ )
{
fr->shortLimit[j][i] = (bandInfo[j].shortIdx[i] - 1) / 18 + 1;
if( fr->shortLimit[j][i] > fr->down_sample_sblimit )
fr->shortLimit[j][i] = fr->down_sample_sblimit;
}
}
}
// read additional side information (for MPEG 1 and MPEG 2)
static int III_get_side_info( mpg123_handle_t *fr, III_sideinfo *si, int stereo, int ms_stereo, long sfreq, int single )
{
int powdiff = (single == SINGLE_MIX) ? 4 : 0;
const int tabs[2][5] = { { 2,9,5,3,4 } , { 1,8,1,2,9 } };
const int *tab = tabs[fr->lsf];
int ch, gr;
si->main_data_begin = getbits( fr, tab[1] );
if( si->main_data_begin > fr->bitreservoir )
{
// overwrite main_data_begin for the floatly available bit reservoir
backbits( fr, tab[1] );
if( fr->lsf == 0 )
{
fr->wordpointer[0] = (byte)(fr->bitreservoir >> 1);
fr->wordpointer[1] = (byte)((fr->bitreservoir & 1) << 7);
}
else fr->wordpointer[0] = (byte)fr->bitreservoir;
// zero "side-info" data for a silence-frame
// without touching audio data used as bit reservoir for following frame
memset( fr->wordpointer + 2, 0, fr->ssize - 2 );
// reread the new bit reservoir offset
si->main_data_begin = getbits( fr, tab[1] );
}
// keep track of the available data bytes for the bit reservoir.
// think: Substract the 2 crc bytes in parser already?
fr->bitreservoir = fr->bitreservoir + fr->framesize - fr->ssize - (fr->error_protection ? 2 : 0);
// limit the reservoir to the max for MPEG 1.0 or 2.x.
if( fr->bitreservoir > (uint)(fr->lsf == 0 ? 511 : 255 ))
fr->bitreservoir = (fr->lsf == 0 ? 511 : 255);
// now back into less commented territory. It's code. It works.
if( stereo == 1 ) si->private_bits = getbits_fast( fr, tab[2] );
else si->private_bits = getbits_fast( fr, tab[3] );
if( !fr->lsf )
{
for( ch = 0; ch < stereo; ch++ )
{
si->ch[ch].gr[0].scfsi = -1;
si->ch[ch].gr[1].scfsi = getbits_fast( fr, 4 );
}
}
for( gr = 0; gr < tab[0]; gr++ )
{
for( ch = 0; ch < stereo; ch++ )
{
register gr_info_t *gr_info = &( si->ch[ch].gr[gr] );
gr_info->part2_3_length = getbits( fr, 12 );
gr_info->big_values = getbits( fr, 9 );
if( gr_info->big_values > 288 )
gr_info->big_values = 288;
gr_info->pow2gain = fr->gainpow2 + 256 - getbits_fast( fr, 8 ) + powdiff;
if( ms_stereo ) gr_info->pow2gain += 2;
gr_info->scalefac_compress = getbits( fr, tab[4] );
if( get1bit( fr ))
{
int i;
// window switch flag
gr_info->block_type = getbits_fast( fr, 2 );
gr_info->mixed_block_flag = get1bit( fr );
gr_info->table_select[0] = getbits_fast( fr, 5 );
gr_info->table_select[1] = getbits_fast( fr, 5 );
// table_select[2] not needed, because there is no region2,
// but to satisfy some verification tools we set it either.
gr_info->table_select[2] = 0;
for( i = 0; i < 3; i++ )
gr_info->full_gain[i] = gr_info->pow2gain + (getbits_fast( fr, 3 ) << 3);
if( gr_info->block_type == 0 )
return 1;
// region_count/start parameters are implicit in this case.
if(( !fr->lsf || ( gr_info->block_type == 2 )) && !fr->mpeg25 )
{
gr_info->region1start = 36 >> 1;
gr_info->region2start = 576 >> 1;
}
else
{
if( fr->mpeg25 )
{
int r0c, r1c;
if(( gr_info->block_type == 2 ) && ( !gr_info->mixed_block_flag ))
r0c = 5;
else r0c = 7;
// r0c + 1 + r1c + 1 == 22, always.
r1c = 20 - r0c;
gr_info->region1start = bandInfo[sfreq].longIdx[r0c+1] >> 1 ;
gr_info->region2start = bandInfo[sfreq].longIdx[r0c+1+r1c+1] >> 1;
}
else
{
gr_info->region1start = 54 >> 1;
gr_info->region2start = 576 >> 1;
}
}
}
else
{
int i, r0c, r1c;
for( i = 0; i < 3; i++ )
gr_info->table_select[i] = getbits_fast( fr, 5 );
r0c = getbits_fast( fr, 4 ); // 0 .. 15
r1c = getbits_fast( fr, 3 ); // 0 .. 7
gr_info->region1start = bandInfo[sfreq].longIdx[r0c+1] >> 1 ;
// max( r0c + r1c + 2 ) = 15 + 7 + 2 = 24
if( r0c + 1 + r1c + 1 > 22 )
gr_info->region2start = 576 >> 1;
else gr_info->region2start = bandInfo[sfreq].longIdx[r0c+1+r1c+1] >> 1;
gr_info->block_type = 0;
gr_info->mixed_block_flag = 0;
}
if( !fr->lsf )
gr_info->preflag = get1bit( fr );
gr_info->scalefac_scale = get1bit( fr );
gr_info->count1table_select = get1bit( fr );
}
}
return 0;
}
// read scalefactors
static int III_get_scale_factors_1( mpg123_handle_t *fr, int *scf, gr_info_t *gr_info )
{
const byte slen[2][16] =
{
{ 0, 0, 0, 0, 3, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4 },
{ 0, 1, 2, 3, 0, 1, 2, 3, 1, 2, 3, 1, 2, 3, 2, 3 }
};
int num0 = slen[0][gr_info->scalefac_compress];
int num1 = slen[1][gr_info->scalefac_compress];
int numbits;
if( gr_info->block_type == 2 )
{
int i = 18;
numbits = (num0 + num1) * 18;
if( gr_info->mixed_block_flag )
{
for( i = 8; i; i-- )
*scf++ = getbits_fast( fr, num0 );
i = 9;
numbits -= num0; // num0 * 17 + num1 * 18
}
for( ; i; i-- )
*scf++ = getbits_fast( fr, num0 );
for( i = 18; i; i-- )
*scf++ = getbits_fast( fr, num1 );
// short[13][0..2] = 0
*scf++ = 0;
*scf++ = 0;
*scf++ = 0;
}
else
{
int i, scfsi = gr_info->scfsi;
if( scfsi < 0 )
{
// scfsi < 0 => granule == 0
for( i = 11; i; i-- )
*scf++ = getbits_fast( fr, num0 );
for( i = 10; i; i-- )
*scf++ = getbits_fast( fr, num1 );
numbits = (num0 + num1) * 10 + num0;
*scf++ = 0;
}
else
{
numbits = 0;
if(!( scfsi & 0x8 ))
{
for( i = 0; i < 6; i++ )
*scf++ = getbits_fast( fr, num0 );
numbits += num0 * 6;
}
else scf += 6;
if(!( scfsi & 0x4 ))
{
for( i = 0; i < 5; i++ )
*scf++ = getbits_fast( fr, num0 );
numbits += num0 * 5;
}
else scf += 5;
if(!( scfsi & 0x2 ))
{
for( i = 0; i < 5; i++ )
*scf++ = getbits_fast( fr, num1 );
numbits += num1 * 5;
}
else scf += 5;
if(!( scfsi & 0x1 ))
{
for( i = 0; i < 5; i++ )
*scf++ = getbits_fast( fr, num1 );
numbits += num1 * 5;
}
else scf += 5;
// no l[21] in original sources
*scf++ = 0;
}
}
return numbits;
}
static int III_get_scale_factors_2( mpg123_handle_t *fr, int *scf, gr_info_t *gr_info, int i_stereo )
{
const byte *pnt;
int i, j, n = 0;
int numbits = 0;
uint slen;
const byte stab[3][6][4] =
{
{
{ 6, 5, 5,5 } , { 6, 5, 7,3 } , { 11,10,0,0},
{ 7, 7, 7,0 } , { 6, 6, 6,3 } , { 8, 8,5,0}
},
{
{ 9, 9, 9,9 } , { 9, 9,12,6 } , { 18,18,0,0},
{12,12,12,0 } , {12, 9, 9,6 } , { 15,12,9,0}
},
{
{ 6, 9, 9,9 } , { 6, 9,12,6 } , { 15,18,0,0},
{ 6,15,12,0 } , { 6,12, 9,6 } , { 6,18,9,0}
}
};
// i_stereo AND second channel -> do_layer3() checks this
if( i_stereo ) slen = i_slen2[gr_info->scalefac_compress>>1];
else slen = n_slen2[gr_info->scalefac_compress];
gr_info->preflag = (slen >> 15) & 0x1;
n = 0;
if( gr_info->block_type == 2 )
{
if( gr_info->mixed_block_flag )
n++;
n++;
}
pnt = stab[n][(slen>>12)&0x7];
for( i = 0; i < 4; i++ )
{
int num = slen & 0x7;
slen >>= 3;
if( num )
{
for( j = 0; j < (int)(pnt[i]); j++ )
*scf++ = getbits_fast( fr, num );
numbits += pnt[i] * num;
}
else
{
for( j = 0; j < (int)(pnt[i]); j++ )
*scf++ = 0;
}
}
n = (n << 1) + 1;
for( i = 0; i < n; i++ )
*scf++ = 0;
return numbits;
}
static int III_dequantize_sample( mpg123_handle_t *fr, float xr[SBLIMIT][SSLIMIT], int *scf, gr_info_t *gr_info, int sfreq, int part2bits )
{
int shift = 1 + gr_info->scalefac_scale;
int part2remain = gr_info->part2_3_length - part2bits;
int region1 = gr_info->region1start;
int region2 = gr_info->region2start;
int bv = gr_info->big_values;
int num = getbitoffset( fr );
float *xrpnt = (float *)xr;
int l[3], l3;
long mask;
int *me;
// we must split this, because for num == 0 the shift is undefined if you do it in one step.
mask = ((ulong)getbits( fr, num )) << BITSHIFT;
mask <<= 8 - num;
part2remain -= num;
l3 = ((576>>1)-bv)>>1;
// we may lose the 'odd' bit here !! check this later again
if( bv <= region1 )
{
l[0] = bv;
l[1] = 0;
l[2] = 0;
}
else
{
l[0] = region1;
if( bv <= region2 )
{
l[1] = bv - l[0];
l[2] = 0;
}
else
{
l[1] = region2 - l[0];
l[2] = bv - region2;
}
}
if( gr_info->block_type == 2 )
{
int i, max[4];
int step = 0;
int lwin = 3;
register float v = 0.0f;
int cb = 0;
register int *m, mc;
int rmax;
// decoding with short or mixed mode BandIndex table
if( gr_info->mixed_block_flag )
{
max[3] = -1;
max[0] = max[1] = max[2] = 2;
m = map[sfreq][0];
me = mapend[sfreq][0];
}
else
{
max[0] = max[1] = max[2] = max[3] = -1;
// max[3] not floatly needed in this case
m = map[sfreq][1];
me = mapend[sfreq][1];
}
mc = 0;
for( i = 0; i < 2; i++ )
{
const struct newhuff *h = ht + gr_info->table_select[i];
int lp = l[i];
for( ; lp; lp--, mc-- )
{
register long x, y;
if( (!mc) )
{
mc = *m++;
xrpnt = ((float *)xr) + (*m++);
lwin = *m++;
cb = *m++;
if( lwin == 3 )
{
v = gr_info->pow2gain[(*scf++) << shift];
step = 1;
}
else
{
v = gr_info->full_gain[lwin][(*scf++) << shift];
step = 3;
}
}
{
const short *val = h->table;
REFRESH_MASK;
while(( y = *val++ ) < 0 )
{
if( mask < 0 )
val -= y;
num--;
mask <<= 1;
}
x = y >> 4;
y &= 0xf;
}
if( x == 15 && h->linbits )
{
max[lwin] = cb;
REFRESH_MASK;
x += ((ulong)mask) >> (BITSHIFT + 8 - h->linbits);
num -= h->linbits + 1;
mask <<= h->linbits;
if( mask < 0 ) *xrpnt = REAL_MUL_SCALE_LAYER3( -ispow[x], v );
else *xrpnt = REAL_MUL_SCALE_LAYER3( ispow[x], v );
mask <<= 1;
}
else if( x )
{
max[lwin] = cb;
if( mask < 0 ) *xrpnt = REAL_MUL_SCALE_LAYER3( -ispow[x], v );
else *xrpnt = REAL_MUL_SCALE_LAYER3( ispow[x], v );
num--;
mask <<= 1;
}
else *xrpnt = DOUBLE_TO_REAL(0.0);
xrpnt += step;
if( y == 15 && h->linbits )
{
max[lwin] = cb;
REFRESH_MASK;
y += ((ulong) mask) >> (BITSHIFT + 8 - h->linbits);
num -= h->linbits + 1;
mask <<= h->linbits;
if( mask < 0 ) *xrpnt = REAL_MUL_SCALE_LAYER3( -ispow[y], v );
else *xrpnt = REAL_MUL_SCALE_LAYER3( ispow[y], v );
mask <<= 1;
}
else if( y )
{
max[lwin] = cb;
if( mask < 0 ) *xrpnt = REAL_MUL_SCALE_LAYER3( -ispow[y], v );
else *xrpnt = REAL_MUL_SCALE_LAYER3( ispow[y], v );
num--;
mask <<= 1;
}
else *xrpnt = DOUBLE_TO_REAL(0.0);
xrpnt += step;
}
}
for( ; l3 && (part2remain + num > 0); l3-- )
{
const struct newhuff *h;
const short *val;
register short a;
// this is only a humble hack to prevent a special segfault.
// more insight into the float workings is still needed.
// especially why there are (valid?) files that make xrpnt exceed the array with 4 bytes without segfaulting
// more seems to be floatly bad, though.
if(!( xrpnt < &xr[SBLIMIT][0] + 5 ))
return 2;
h = htc + gr_info->count1table_select;
val = h->table;
REFRESH_MASK;
while(( a = *val++ ) < 0 )
{
if( mask < 0 )
val -= a;
num--;
mask <<= 1;
}
if( part2remain + num <= 0 )
{
num -= part2remain + num;
break;
}
for( i = 0; i < 4; i++ )
{
if(!( i & 1 ))
{
if( !mc )
{
mc = *m++;
xrpnt = ((float *)xr) + (*m++);
lwin = *m++;
cb = *m++;
if( lwin == 3 )
{
v = gr_info->pow2gain[(*scf++) << shift];
step = 1;
}
else
{
v = gr_info->full_gain[lwin][(*scf++) << shift];
step = 3;
}
}
mc--;
}
if(( a & ( 0x8 >> i )))
{
max[lwin] = cb;
if( part2remain + num <= 0 )
break;
if( mask < 0 ) *xrpnt = -REAL_SCALE_LAYER3( v );
else *xrpnt = REAL_SCALE_LAYER3( v );
num--;
mask <<= 1;
}
else *xrpnt = DOUBLE_TO_REAL( 0.0 );
xrpnt += step;
}
}
if( lwin < 3 )
{
// short band?
while( 1 )
{
for( ; mc > 0; mc-- )
{
*xrpnt = DOUBLE_TO_REAL( 0.0 );
xrpnt += 3; // short band -> step = 3
*xrpnt = DOUBLE_TO_REAL( 0.0 );
xrpnt += 3;
}
if( m >= me ) break;
mc = *m++;
xrpnt = ((float *)xr) + *m++;
if( *m++ == 0 ) break; // optimize: field will be set to zero at the end of the function
m++; // cb
}
}
gr_info->maxband[0] = max[0]+1;
gr_info->maxband[1] = max[1]+1;
gr_info->maxband[2] = max[2]+1;
gr_info->maxbandl = max[3]+1;
rmax = max[0] > max[1] ? max[0] : max[1];
rmax = (rmax > max[2] ? rmax : max[2]) + 1;
gr_info->maxb = rmax ? fr->shortLimit[sfreq][rmax] : fr->longLimit[sfreq][max[3]+1];
}
else
{
// decoding with 'long' BandIndex table (block_type != 2)
const byte *pretab = pretab_choice[gr_info->preflag];
int *m = map[sfreq][2];
int i,max = -1;
int cb = 0;
register float v = 0.0;
int mc = 0;
// long hash table values
for( i = 0; i < 3; i++ )
{
const struct newhuff *h = ht + gr_info->table_select[i];
int lp = l[i];
for( ; lp; lp--, mc-- )
{
long x, y;
if( !mc )
{
mc = *m++;
cb = *m++;
v = gr_info->pow2gain[(*(scf++) + (*pretab++)) << shift];
}
{
const short *val = h->table;
REFRESH_MASK;
while(( y = *val++ ) < 0 )
{
if( mask < 0 )
val -= y;
num--;
mask <<= 1;
}
x = y >> 4;
y &= 0xf;
}
if( x == 15 && h->linbits )
{
max = cb;
REFRESH_MASK;
x += ((ulong)mask) >> (BITSHIFT + 8 - h->linbits);
num -= h->linbits+1;
mask <<= h->linbits;
if( mask < 0 ) *xrpnt++ = REAL_MUL_SCALE_LAYER3(-ispow[x], v );
else *xrpnt++ = REAL_MUL_SCALE_LAYER3( ispow[x], v );
mask <<= 1;
}
else if( x )
{
max = cb;
if( mask < 0 ) *xrpnt++ = REAL_MUL_SCALE_LAYER3( -ispow[x], v );
else *xrpnt++ = REAL_MUL_SCALE_LAYER3( ispow[x], v );
num--;
mask <<= 1;
}
else *xrpnt++ = DOUBLE_TO_REAL( 0.0 );
if( y == 15 && h->linbits )
{
max = cb;
REFRESH_MASK;
y += ((ulong)mask) >> (BITSHIFT + 8 - h->linbits);
num -= h->linbits+1;
mask <<= h->linbits;
if( mask < 0 ) *xrpnt++ = REAL_MUL_SCALE_LAYER3( -ispow[y], v );
else *xrpnt++ = REAL_MUL_SCALE_LAYER3( ispow[y], v );
mask <<= 1;
}
else if( y )
{
max = cb;
if( mask < 0 ) *xrpnt++ = REAL_MUL_SCALE_LAYER3( -ispow[y], v );
else *xrpnt++ = REAL_MUL_SCALE_LAYER3( ispow[y], v );
num--;
mask <<= 1;
}
else *xrpnt++ = DOUBLE_TO_REAL( 0.0 );
}
}
// short (count1table) values
for( ; l3 && (part2remain + num > 0); l3-- )
{
const struct newhuff *h = htc+gr_info->count1table_select;
const short *val = h->table;
register short a;
REFRESH_MASK;
while(( a = *val++ ) < 0 )
{
if( mask < 0 )
val -= a;
num--;
mask <<= 1;
}
if( part2remain + num <= 0 )
{
num -= part2remain + num;
break;
}
for( i = 0; i < 4; i++ )
{
if(!( i & 1 ))
{
if( !mc )
{
mc = *m++;
cb = *m++;
v = gr_info->pow2gain[((*scf++) + (*pretab++)) << shift];
}
mc--;
}
if(( a & (0x8 >> i)))
{
max = cb;
if( part2remain + num <= 0 )
break;
if( mask < 0 ) *xrpnt++ = -REAL_SCALE_LAYER3( v );
else *xrpnt++ = REAL_SCALE_LAYER3( v );
num--;
mask <<= 1;
}
else *xrpnt++ = DOUBLE_TO_REAL( 0.0 );
}
}
gr_info->maxbandl = max+1;
gr_info->maxb = fr->longLimit[sfreq][gr_info->maxbandl];
}
part2remain += num;
backbits( fr, num );
num = 0;
while( xrpnt < &xr[SBLIMIT][0] )
*xrpnt++ = DOUBLE_TO_REAL( 0.0 );
while( part2remain > 16 )
{
skipbits( fr, 16 ); // dismiss stuffing Bits
part2remain -= 16;
}
if( part2remain > 0 )
{
skipbits( fr, part2remain );
}
else if( part2remain < 0 )
{
// error
return 1;
}
return 0;
}
// calculate float channel values for Joint-I-Stereo-mode
static void III_i_stereo( float xr_buf[2][SBLIMIT][SSLIMIT], int *scalefac, gr_info_t *gr_info, int sfreq, int ms_stereo, int lsf )
{
float (*xr)[SBLIMIT*SSLIMIT] = (float(*)[SBLIMIT*SSLIMIT])xr_buf;
const bandInfoStruct *bi = &bandInfo[sfreq];
const float *tab1, *tab2;
int tab;
// TODO: optimize as static
const float *tabs[3][2][2] =
{
{ { tan1_1,tan2_1 } , { tan1_2,tan2_2 } },
{ { pow1_1[0],pow2_1[0] } , { pow1_2[0],pow2_2[0] } },
{ { pow1_1[1],pow2_1[1] } , { pow1_2[1],pow2_2[1] } }
};
tab = lsf + (gr_info->scalefac_compress & lsf);
tab1 = tabs[tab][ms_stereo][0];
tab2 = tabs[tab][ms_stereo][1];
if( gr_info->block_type == 2 )
{
int lwin, do_l = 0;
if( gr_info->mixed_block_flag )
do_l = 1;
for( lwin = 0; lwin < 3; lwin++ )
{
int is_p, sb, idx;
int sfb = gr_info->maxband[lwin]; // sfb is minimal 3 for mixed mode
if( sfb > 3 ) do_l = 0;
// process each window
// get first band with zero values
for( ; sfb < 12; sfb++ )
{
is_p = scalefac[sfb * 3 + lwin - gr_info->mixed_block_flag]; // scale: 0-15
if( is_p != 7 )
{
float t1, t2;
sb = bi->shortDiff[sfb];
idx = bi->shortIdx[sfb] + lwin;
t1 = tab1[is_p];
t2 = tab2[is_p];
for( ; sb > 0; sb--, idx += 3 )
{
float v = xr[0][idx];
xr[0][idx] = REAL_MUL_15( v, t1 );
xr[1][idx] = REAL_MUL_15( v, t2 );
}
}
}
// in the original: copy 10 to 11 , here: copy 11 to 12
// maybe still wrong??? (copy 12 to 13?)
is_p = scalefac[11 * 3 + lwin - gr_info->mixed_block_flag]; // scale: 0-15
sb = bi->shortDiff[12];
idx = bi->shortIdx[12] + lwin;
if( is_p != 7 )
{
float t1, t2;
t1 = tab1[is_p];
t2 = tab2[is_p];
for( ; sb > 0; sb--, idx += 3 )
{
float v = xr[0][idx];
xr[0][idx] = REAL_MUL_15( v, t1 );
xr[1][idx] = REAL_MUL_15( v, t2 );
}
}
}
// also check l-part, if ALL bands in the three windows are 'empty' and mode = mixed_mode
if( do_l )
{
int idx, sfb = gr_info->maxbandl;
if( sfb > 21 ) return; // similarity fix related to CVE-2006-1655
idx = bi->longIdx[sfb];
for( ; sfb < 8; sfb++ )
{
int sb = bi->longDiff[sfb];
int is_p = scalefac[sfb]; // scale: 0-15
if( is_p != 7 )
{
float t1, t2;
t1 = tab1[is_p];
t2 = tab2[is_p];
for( ; sb > 0; sb--, idx++ )
{
float v = xr[0][idx];
xr[0][idx] = REAL_MUL_15( v, t1 );
xr[1][idx] = REAL_MUL_15( v, t2 );
}
}
else idx += sb;
}
}
}
else
{
int sfb = gr_info->maxbandl;
int is_p, idx;
if( sfb > 21 ) return; // tightened fix for CVE-2006-1655
idx = bi->longIdx[sfb];
for( ; sfb < 21; sfb++ )
{
int sb = bi->longDiff[sfb];
is_p = scalefac[sfb]; // scale: 0-15
if( is_p != 7 )
{
float t1, t2;
t1 = tab1[is_p];
t2 = tab2[is_p];
for( ; sb > 0; sb--, idx++ )
{
float v = xr[0][idx];
xr[0][idx] = REAL_MUL_15( v, t1 );
xr[1][idx] = REAL_MUL_15( v, t2 );
}
}
else idx += sb;
}
is_p = scalefac[20];
if( is_p != 7 )
{
float t1, t2;
int sb;
t1 = tab1[is_p],
t2 = tab2[is_p];
// copy l-band 20 to l-band 21
for( sb = bi->longDiff[21]; sb > 0; sb--, idx++ )
{
float v = xr[0][idx];
xr[0][idx] = REAL_MUL_15( v, t1 );
xr[1][idx] = REAL_MUL_15( v, t2 );
}
}
}
}
static void III_antialias( float xr[SBLIMIT][SSLIMIT], gr_info_t *gr_info )
{
int sblim, sb;
float *xr1;
if( gr_info->block_type == 2 )
{
if( !gr_info->mixed_block_flag )
return;
sblim = 1;
}
else
{
sblim = gr_info->maxb-1;
}
// 31 alias-reduction operations between each pair of sub-bands
// with 8 butterflies between each pair
xr1 = (float *)xr[1];
for( sb = sblim; sb; sb--, xr1 += 10 )
{
float *cs = aa_cs;
float *ca = aa_ca;
float *xr2 = xr1;
int ss;
for( ss = 7; ss >= 0; ss-- )
{
// upper and lower butterfly inputs
register float bu = *--xr2;
register float bd = *xr1;
*xr2 = REAL_MUL( bu, *cs ) - REAL_MUL( bd, *ca );
*xr1++ = REAL_MUL( bd, *cs++ ) + REAL_MUL( bu, *ca++ );
}
}
}
static void III_hybrid( float fsIn[SBLIMIT][SSLIMIT], float tsOut[SSLIMIT][SBLIMIT], int ch, gr_info_t *gr_info, mpg123_handle_t *fr )
{
float (*block)[2][SBLIMIT*SSLIMIT] = fr->hybrid_block;
int *blc = fr->hybrid_blc;
float *tspnt = (float *)tsOut;
float *rawout1, *rawout2;
int bt = 0, b, i;
size_t sb = 0;
b = blc[ch];
rawout1 = block[b][ch];
b=-b + 1;
rawout2 = block[b][ch];
blc[ch] = b;
if( gr_info->mixed_block_flag )
{
sb = 2;
dct36( fsIn[0], rawout1, rawout2, win[0], tspnt );
dct36( fsIn[1], rawout1+18, rawout2+18, win1[0], tspnt + 1 );
rawout1 += 36; rawout2 += 36; tspnt += 2;
}
bt = gr_info->block_type;
if( bt == 2 )
{
for( ; sb < gr_info->maxb; sb += 2, tspnt += 2, rawout1 += 36, rawout2 += 36 )
{
dct12( fsIn[sb], rawout1, rawout2, win[2], tspnt );
dct12( fsIn[sb+1], rawout1 + 18, rawout2 + 18, win1[2], tspnt + 1 );
}
}
else
{
for( ; sb < gr_info->maxb; sb += 2, tspnt += 2, rawout1 += 36, rawout2 += 36 )
{
dct36( fsIn[sb], rawout1, rawout2, win[bt], tspnt );
dct36( fsIn[sb+1], rawout1 + 18, rawout2 + 18, win1[bt], tspnt + 1 );
}
}
for( ; sb < SBLIMIT; sb++, tspnt++ )
{
for( i = 0; i < SSLIMIT; i++ )
{
tspnt[i*SBLIMIT] = *rawout1++;
*rawout2++ = DOUBLE_TO_REAL( 0.0 );
}
}
}
// and at the end... the main layer3 handler
int do_layer3( mpg123_handle_t *fr )
{
int gr, ch, ss, clip = 0;
int stereo = fr->stereo;
int single = fr->single;
int ms_stereo, i_stereo;
int sfreq = fr->sampling_frequency;
int scalefacs[2][39]; // max 39 for short[13][3] mode, mixed: 38, long: 22
int stereo1, granules;
III_sideinfo sideinfo;
if( stereo == 1 )
{
// stream is mono
stereo1 = 1;
single = SINGLE_LEFT;
}
else if( single != SINGLE_STEREO )
{
// stream is stereo, but force to mono
stereo1 = 1;
}
else
{
stereo1 = 2;
}
if( fr->mode == MPG_MD_JOINT_STEREO )
{
ms_stereo = (fr->mode_ext & 0x2) >> 1;
i_stereo = fr->mode_ext & 0x1;
}
else
{
ms_stereo = i_stereo = 0;
}
granules = fr->lsf ? 1 : 2;
// quick hack to keep the music playing
// after having seen this nasty test file...
if( III_get_side_info( fr, &sideinfo, stereo, ms_stereo, sfreq, single ))
return clip;
set_pointer( fr, sideinfo.main_data_begin );
for( gr = 0; gr < granules; gr++ )
{
float (*hybridIn)[SBLIMIT][SSLIMIT] = fr->layer3.hybrid_in; // hybridIn[2][SBLIMIT][SSLIMIT]
float (*hybridOut)[SSLIMIT][SBLIMIT] = fr->layer3.hybrid_out; // hybridOut[2][SSLIMIT][SBLIMIT]
gr_info_t *gr_info = &(sideinfo.ch[0].gr[gr]);
long part2bits;
if( fr->lsf ) part2bits = III_get_scale_factors_2( fr, scalefacs[0], gr_info, 0 );
else part2bits = III_get_scale_factors_1( fr, scalefacs[0], gr_info );
if( III_dequantize_sample( fr, hybridIn[0], scalefacs[0], gr_info, sfreq, part2bits ))
return clip;
if( stereo == 2 )
{
register float *in0, *in1;
register int i;
gr_info = &(sideinfo.ch[1].gr[gr]);
if( fr->lsf ) part2bits = III_get_scale_factors_2( fr, scalefacs[1], gr_info, i_stereo );
else part2bits = III_get_scale_factors_1( fr, scalefacs[1], gr_info );
if( III_dequantize_sample( fr, hybridIn[1], scalefacs[1], gr_info, sfreq, part2bits ))
return clip;
if( ms_stereo )
{
uint maxb = sideinfo.ch[0].gr[gr].maxb;
int i;
if( sideinfo.ch[1].gr[gr].maxb > maxb )
maxb = sideinfo.ch[1].gr[gr].maxb;
for( i = 0; i < SSLIMIT * (int)maxb; i++ )
{
float tmp0 = ((float *)hybridIn[0])[i];
float tmp1 = ((float *)hybridIn[1])[i];
((float *)hybridIn[0])[i] = tmp0 + tmp1;
((float *)hybridIn[1])[i] = tmp0 - tmp1;
}
}
if( i_stereo )
III_i_stereo( hybridIn, scalefacs[1], gr_info, sfreq, ms_stereo, fr->lsf );
if( ms_stereo || i_stereo || ( single == SINGLE_MIX ))
{
if( gr_info->maxb > sideinfo.ch[0].gr[gr].maxb )
sideinfo.ch[0].gr[gr].maxb = gr_info->maxb;
else gr_info->maxb = sideinfo.ch[0].gr[gr].maxb;
}
switch( single )
{
case SINGLE_MIX:
in0 = (float *)hybridIn[0];
in1 = (float *)hybridIn[1];
for( i = 0; i < SSLIMIT * (int)gr_info->maxb; i++, in0++ )
*in0 = (*in0 + *in1++); // *0.5 done by pow-scale
break;
case SINGLE_RIGHT:
in0 = (float *)hybridIn[0];
in1 = (float *)hybridIn[1];
for( i = 0; i < SSLIMIT * (int)gr_info->maxb; i++ )
*in0++ = *in1++;
break;
}
}
for( ch = 0; ch < stereo1; ch++ )
{
gr_info = &(sideinfo.ch[ch].gr[gr]);
III_antialias( hybridIn[ch], gr_info );
III_hybrid( hybridIn[ch], hybridOut[ch], ch,gr_info, fr );
}
for( ss = 0; ss < SSLIMIT; ss++ )
{
if( single != SINGLE_STEREO )
clip += (fr->synth_mono)(hybridOut[0][ss], fr );
else clip += (fr->synth_stereo)(hybridOut[0][ss], hybridOut[1][ss], fr );
}
}
return clip;
}