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/*****************************************************************************
* layer2.c: MPEG Layer II audio decoder
*****************************************************************************
* Copyright (C) 1999-2001 VideoLAN
* $Id: layer2.c,v 1.4 2002/08/26 23:00:22 massiot Exp $
*
* Authors: Michel Kaempf <maxx@via.ecp.fr>
* Michel Lespinasse <walken@via.ecp.fr>
*
* 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 2 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
*****************************************************************************/
#include <stdlib.h> /* NULL */
#include <string.h> /* memcpy(), memset() */
#include <vlc/vlc.h>
#include <vlc/decoder.h>
#include <vlc/aout.h>
#include "generic.h"
#include "decoder.h"
#include "math.h" /* DCT32(), PCM() */
/**** wkn ****/
static float adec_scalefactor_table[64] =
{ /* 2 ^ (1 - i/3) */
2.0000000000000000, 1.5874010519681994, 1.2599210498948732,
1.0000000000000000, 0.7937005259840998, 0.6299605249474366,
0.5000000000000000, 0.3968502629920499, 0.3149802624737183,
0.2500000000000000, 0.1984251314960249, 0.1574901312368591,
0.1250000000000000, 0.0992125657480125, 0.0787450656184296,
0.0625000000000000, 0.0496062828740062, 0.0393725328092148,
0.0312500000000000, 0.0248031414370031, 0.0196862664046074,
0.0156250000000000, 0.0124015707185016, 0.0098431332023037,
0.0078125000000000, 0.0062007853592508, 0.0049215666011518,
0.0039062500000000, 0.0031003926796254, 0.0024607833005759,
0.0019531250000000, 0.0015501963398127, 0.0012303916502880,
0.0009765625000000, 0.0007750981699063, 0.0006151958251440,
0.0004882812500000, 0.0003875490849532, 0.0003075979125720,
0.0002441406250000, 0.0001937745424766, 0.0001537989562860,
0.0001220703125000, 0.0000968872712383, 0.0000768994781430,
0.0000610351562500, 0.0000484436356191, 0.0000384497390715,
0.0000305175781250, 0.0000242218178096, 0.0000192248695357,
0.0000152587890625, 0.0000121109089048, 0.0000096124347679,
0.0000076293945312, 0.0000060554544524, 0.0000048062173839,
0.0000038146972656, 0.0000030277272262, 0.0000024031086920,
0.0000019073486328, 0.0000015138636131, 0.0000012015543460,
0.0000009536743164 /* last element is not in the standard... invalid ??? */
};
static float adec_slope_table[15] =
{
0.6666666666666666, 0.2857142857142857, 0.1333333333333333,
0.0645161290322581, 0.0317460317460317, 0.0157480314960630,
0.0078431372549020, 0.0039138943248532, 0.0019550342130987,
0.0009770395701026, 0.0004884004884005, 0.0002441704309608,
0.0001220777635354, 0.0000610370189520, 0.0000305180437934
};
static float adec_offset_table[15] =
{
-0.6666666666666666, -0.8571428571428571, -0.9333333333333333,
-0.9677419354838710, -0.9841269841269841, -0.9921259842519685,
-0.9960784313725490, -0.9980430528375733, -0.9990224828934506,
-0.9995114802149487, -0.9997557997557998, -0.9998779147845196,
-0.9999389611182323, -0.9999694814905240, -0.9999847409781033
};
static int adec_bound_table[4] = { 4, 8, 12, 16 };
typedef struct
{
s8 nbal[32];
s8 * alloc[32];
} alloc_table_t;
#define L3 -1
#define L5 -2
#define L9 -3
static void adec_layer2_get_table( u32 header, u8 freq_table[15],
alloc_table_t ** alloc, int * sblimit )
{
static s8 table_ab0[16] =
{
0, L3, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
};
static s8 table_ab3[16] =
{
0, L3, L5, 3, L9, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 16
};
static s8 table_ab11[8] =
{
0, L3, L5, 3, L9, 4, 5, 16
};
static s8 table_ab23[8] =
{
0, L3, L5, 16
};
static alloc_table_t mpeg1_ab =
{
{4,4,4,4,4,4,4,4,4,4,4,3,3,3,3,3,3,3,3,3,3,3,3,2,2,2,2,2,2,2,0,0},
{table_ab0, table_ab0, table_ab0, table_ab3,
table_ab3, table_ab3, table_ab3, table_ab3,
table_ab3, table_ab3, table_ab3, table_ab11,
table_ab11, table_ab11, table_ab11, table_ab11,
table_ab11, table_ab11, table_ab11, table_ab11,
table_ab11, table_ab11, table_ab11, table_ab23,
table_ab23, table_ab23, table_ab23, table_ab23,
table_ab23, table_ab23, NULL, NULL}
};
static s8 table_cd[16] =
{
0, L3, L5, L9, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
};
static alloc_table_t mpeg1_cd =
{
{4,4,3,3,3,3,3,3,3,3,3,3,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
{table_cd, table_cd, table_cd, table_cd,
table_cd, table_cd, table_cd, table_cd,
table_cd, table_cd, table_cd, table_cd,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL}
};
static s8 table_0[16] =
{
0, L3, L5, 3, L9, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
};
static s8 table_4[8] =
{
0, L3, L5, L9, 4, 5, 6, 7
};
static alloc_table_t mpeg2 =
{
{4,4,4,4,3,3,3,3,3,3,3,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,0,0},
{table_0, table_0, table_0, table_0,
table_4, table_4, table_4, table_4,
table_4, table_4, table_4, table_4,
table_4, table_4, table_4, table_4,
table_4, table_4, table_4, table_4,
table_4, table_4, table_4, table_4,
table_4, table_4, table_4, table_4,
table_4, table_4, NULL, NULL}
};
static alloc_table_t * alloc_table [4] =
{
&mpeg2, &mpeg1_cd, &mpeg1_ab, &mpeg1_ab
};
static int sblimit_table[12] =
{
30, 8, 27, 30, 30, 8, 27, 27, 30, 12, 27, 30
};
int index;
if (!(header & 0x80000))
{
index = 0; /* mpeg2 */
}
else
{
index = (header >> 12) & 15; /* mpeg1, bitrate */
index = freq_table [index];
}
*alloc = alloc_table[index];
index |= (header >> 8) & 12;
*sblimit = sblimit_table[index];
}
int adec_layer2_mono( adec_thread_t * p_adec, float * buffer )
{
static u8 freq_table[15] = {2, 1, 1, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2};
static float L3_table[3] = {-2/3.0, 0, 2/3.0};
static float L5_table[5] = {-4/5.0, -2/5.0, 0, 2/5.0, 4/5.0};
static float L9_table[9] = {-8/9.0, -6/9.0, -4/9.0, -2/9.0, 0,
2/9.0, 4/9.0, 6/9.0, 8/9.0};
s8 allocation[32];
u8 scfsi[32];
float slope[3][32];
float offset[3][32];
float sample[3][32];
alloc_table_t * alloc_table;
int sblimit;
int sb;
int gr0, gr1;
int s;
int i_read_bits = 0;
/* get the right allocation table */
adec_layer2_get_table (p_adec->header, freq_table, &alloc_table, &sblimit);
/* parse allocation */
/*sblimit=27;*/
for (sb = 0; sb < sblimit; sb++)
{
int index;
index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
i_read_bits += alloc_table->nbal[sb];
allocation[sb] = alloc_table->alloc[sb][index];
}
/* parse scfsi */
for (sb = 0; sb < sblimit; sb++)
{
if (allocation[sb])
{
scfsi[sb] = GetBits (&p_adec->bit_stream, 2);
i_read_bits += 2;
}
}
/* parse scalefactors */
for (sb = 0; sb < sblimit; sb++)
{
if (allocation[sb])
{
int index_0, index_1, index_2;
switch (scfsi[sb])
{
case 0:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
index_2 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 18;
if (allocation[sb] < 0)
{
slope[0][sb] = adec_scalefactor_table[index_0];
slope[1][sb] = adec_scalefactor_table[index_1];
slope[2][sb] = adec_scalefactor_table[index_2];
}
else
{
float r_scalefactor;
float r_slope, r_offset;
r_slope = adec_slope_table[allocation[sb]-2];
r_offset = adec_offset_table[allocation[sb]-2];
r_scalefactor = adec_scalefactor_table[index_0];
slope[0][sb] = r_slope * r_scalefactor;
offset[0][sb] = r_offset * r_scalefactor;
r_scalefactor = adec_scalefactor_table[index_1];
slope[1][sb] = r_slope * r_scalefactor;
offset[1][sb] = r_offset * r_scalefactor;
r_scalefactor = adec_scalefactor_table[index_2];
slope[2][sb] = r_slope * r_scalefactor;
offset[2][sb] = r_offset * r_scalefactor;
}
break;
case 1:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 12;
if (allocation[sb] < 0)
{
slope[0][sb] = slope[1][sb] =
adec_scalefactor_table[index_0];
slope[2][sb] = adec_scalefactor_table[index_1];
}
else
{
float r_scalefactor;
float r_slope, r_offset;
r_slope = adec_slope_table[allocation[sb]-2];
r_offset = adec_offset_table[allocation[sb]-2];
r_scalefactor = adec_scalefactor_table[index_0];
slope[0][sb] = slope[1][sb] = r_slope * r_scalefactor;
offset[0][sb] = offset[1][sb] =
r_offset * r_scalefactor;
r_scalefactor = adec_scalefactor_table[index_1];
slope[2][sb] = r_slope * r_scalefactor;
offset[2][sb] = r_offset * r_scalefactor;
}
break;
case 2:
index_0 = GetBits( &p_adec->bit_stream, 6 );
i_read_bits += 6;
if (allocation[sb] < 0)
{
slope[0][sb] = slope[1][sb] = slope[2][sb] =
adec_scalefactor_table[index_0];
}
else
{
float r_scalefactor;
float r_slope, r_offset;
r_slope = adec_slope_table[allocation[sb]-2];
r_offset = adec_offset_table[allocation[sb]-2];
r_scalefactor = adec_scalefactor_table[index_0];
slope[0][sb] = slope[1][sb] = slope[2][sb] =
r_slope * r_scalefactor;
offset[0][sb] = offset[1][sb] = offset[2][sb] =
r_offset * r_scalefactor;
}
break;
case 3:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 12;
if (allocation[sb] < 0)
{
slope[0][sb] = adec_scalefactor_table[index_0];
slope[1][sb] = slope[2][sb] =
adec_scalefactor_table[index_1];
}
else
{
float r_scalefactor;
float r_slope, r_offset;
r_slope = adec_slope_table[allocation[sb]-2];
r_offset = adec_offset_table[allocation[sb]-2];
r_scalefactor = adec_scalefactor_table[index_0];
slope[0][sb] = r_slope * r_scalefactor;
offset[0][sb] = r_offset * r_scalefactor;
r_scalefactor = adec_scalefactor_table[index_1];
slope[1][sb] = slope[2][sb] = r_slope * r_scalefactor;
offset[1][sb] = offset[2][sb] =
r_offset * r_scalefactor;
}
break;
}
}
}
/* parse samples */
for (gr0 = 0; gr0 < 3; gr0++)
{
for (gr1 = 0; gr1 < 4; gr1++)
{
for (sb = 0; sb < sblimit; sb++)
{
int code;
switch (allocation[sb])
{
case 0:
sample[0][sb] = sample[1][sb] = sample[2][sb] = 0;
break;
case L3:
code = GetBits( &p_adec->bit_stream, 5 );
i_read_bits += 5;
sample[0][sb] = slope[gr0][sb] * L3_table[code % 3];
code /= 3;
sample[1][sb] = slope[gr0][sb] * L3_table[code % 3];
code /= 3;
sample[2][sb] = slope[gr0][sb] * L3_table[code];
break;
case L5:
code = GetBits( &p_adec->bit_stream, 7 );
i_read_bits += 7;
sample[0][sb] = slope[gr0][sb] * L5_table[code % 5];
code /= 5;
sample[1][sb] = slope[gr0][sb] * L5_table[code % 5];
code /= 5;
sample[2][sb] = slope[gr0][sb] * L5_table[code];
break;
case L9:
code = GetBits( &p_adec->bit_stream, 10 );
i_read_bits += 10;
sample[0][sb] = slope[gr0][sb] * L9_table[code % 9];
code /= 9;
sample[1][sb] = slope[gr0][sb] * L9_table[code % 9];
code /= 9;
sample[2][sb] = slope[gr0][sb] * L9_table[code];
break;
default:
for (s = 0; s < 3; s++)
{
code = GetBits( &p_adec->bit_stream,
allocation[sb] );
i_read_bits += allocation[sb];
sample[s][sb] =
slope[gr0][sb] * code + offset[gr0][sb];
}
}
}
for (; sb < 32; sb++)
{
sample[0][sb] = sample[1][sb] = sample[2][sb] = 0;
}
for (s = 0; s < 3; s++)
{
DCT32( &p_adec->bank_0, sample[s] );
PCM( &p_adec->bank_0, buffer, 1 );
buffer += 32;
}
}
}
p_adec->i_read_bits += i_read_bits;
return 0;
}
int adec_layer2_stereo( adec_thread_t * p_adec, float * buffer )
{
static u8 freq_table[15] = {3, 0, 0, 0, 1, 0, 1, 2, 2, 2, 3, 3, 3, 3, 3};
static float L3_table[3] = {-2/3.0, 0, 2/3.0};
static float L5_table[5] = {-4/5.0, -2/5.0, 0, 2/5.0, 4/5.0};
static float L9_table[9] = {-8/9.0, -6/9.0, -4/9.0, -2/9.0, 0,
2/9.0, 4/9.0, 6/9.0, 8/9.0};
s8 allocation_0[32], allocation_1[32];
u8 scfsi_0[32], scfsi_1[32];
float slope_0[3][32], slope_1[3][32];
float offset_0[3][32], offset_1[3][32];
float sample_0[3][32], sample_1[3][32];
alloc_table_t * alloc_table;
int sblimit;
int bound;
int sb;
int gr0, gr1;
int s;
int i_read_bits = 0;
/* get the right allocation table */
adec_layer2_get_table (p_adec->header, freq_table, &alloc_table, &sblimit);
/* calculate bound */
bound = sblimit;
if ((p_adec->header & 0xc0) == 0x40) { /* intensity stereo */
int index;
index = (p_adec->header >> 4) & 3;
if (adec_bound_table[index] < sblimit)
{
bound = adec_bound_table[index];
}
}
/* parse allocation */
for (sb = 0; sb < bound; sb++)
{
int index;
index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
allocation_0[sb] = alloc_table->alloc[sb][index];
index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
allocation_1[sb] = alloc_table->alloc[sb][index];
i_read_bits += alloc_table->nbal[sb] * 2;
}
for (; sb < sblimit; sb++)
{
int index;
index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
allocation_0[sb] = allocation_1[sb] = alloc_table->alloc[sb][index];
i_read_bits += alloc_table->nbal[sb];
}
/* parse scfsi */
for (sb = 0; sb < sblimit; sb++)
{
if (allocation_0[sb])
{
scfsi_0[sb] = GetBits (&p_adec->bit_stream, 2);
i_read_bits += 2;
}
if (allocation_1[sb])
{
scfsi_1[sb] = GetBits (&p_adec->bit_stream, 2);
i_read_bits += 2;
}
}
/* parse scalefactors */
for (sb = 0; sb < sblimit; sb++)
{
if (allocation_0[sb])
{
int index_0, index_1, index_2;
switch (scfsi_0[sb])
{
case 0:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
index_2 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 18;
if (allocation_0[sb] < 0)
{
slope_0[0][sb] = adec_scalefactor_table[index_0];
slope_0[1][sb] = adec_scalefactor_table[index_1];
slope_0[2][sb] = adec_scalefactor_table[index_2];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_0[sb]-2];
offset = adec_offset_table[allocation_0[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_0[0][sb] = slope * scalefactor;
offset_0[0][sb] = offset * scalefactor;
scalefactor = adec_scalefactor_table[index_1];
slope_0[1][sb] = slope * scalefactor;
offset_0[1][sb] = offset * scalefactor;
scalefactor = adec_scalefactor_table[index_2];
slope_0[2][sb] = slope * scalefactor;
offset_0[2][sb] = offset * scalefactor;
}
break;
case 1:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 12;
if (allocation_0[sb] < 0)
{
slope_0[0][sb] = slope_0[1][sb] =
adec_scalefactor_table[index_0];
slope_0[2][sb] = adec_scalefactor_table[index_1];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_0[sb]-2];
offset = adec_offset_table[allocation_0[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_0[0][sb] = slope_0[1][sb] = slope * scalefactor;
offset_0[0][sb] = offset_0[1][sb] =
offset * scalefactor;
scalefactor = adec_scalefactor_table[index_1];
slope_0[2][sb] = slope * scalefactor;
offset_0[2][sb] = offset * scalefactor;
}
break;
case 2:
index_0 = GetBits( &p_adec->bit_stream, 6 );
i_read_bits += 6;
if (allocation_0[sb] < 0)
{
slope_0[0][sb] = slope_0[1][sb] = slope_0[2][sb] =
adec_scalefactor_table[index_0];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_0[sb]-2];
offset = adec_offset_table[allocation_0[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_0[0][sb] = slope_0[1][sb] = slope_0[2][sb] =
slope * scalefactor;
offset_0[0][sb] = offset_0[1][sb] = offset_0[2][sb] =
offset * scalefactor;
}
break;
case 3:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 12;
if (allocation_0[sb] < 0)
{
slope_0[0][sb] = adec_scalefactor_table[index_0];
slope_0[1][sb] = slope_0[2][sb] =
adec_scalefactor_table[index_1];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_0[sb]-2];
offset = adec_offset_table[allocation_0[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_0[0][sb] = slope * scalefactor;
offset_0[0][sb] = offset * scalefactor;
scalefactor = adec_scalefactor_table[index_1];
slope_0[1][sb] = slope_0[2][sb] = slope * scalefactor;
offset_0[1][sb] = offset_0[2][sb] =
offset * scalefactor;
}
break;
}
}
if (allocation_1[sb])
{
int index_0, index_1, index_2;
switch (scfsi_1[sb])
{
case 0:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
index_2 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 18;
if (allocation_1[sb] < 0)
{
slope_1[0][sb] = adec_scalefactor_table[index_0];
slope_1[1][sb] = adec_scalefactor_table[index_1];
slope_1[2][sb] = adec_scalefactor_table[index_2];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_1[sb]-2];
offset = adec_offset_table[allocation_1[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_1[0][sb] = slope * scalefactor;
offset_1[0][sb] = offset * scalefactor;
scalefactor = adec_scalefactor_table[index_1];
slope_1[1][sb] = slope * scalefactor;
offset_1[1][sb] = offset * scalefactor;
scalefactor = adec_scalefactor_table[index_2];
slope_1[2][sb] = slope * scalefactor;
offset_1[2][sb] = offset * scalefactor;
}
break;
case 1:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 12;
if (allocation_1[sb] < 0)
{
slope_1[0][sb] = slope_1[1][sb] =
adec_scalefactor_table[index_0];
slope_1[2][sb] = adec_scalefactor_table[index_1];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_1[sb]-2];
offset = adec_offset_table[allocation_1[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_1[0][sb] = slope_1[1][sb] = slope * scalefactor;
offset_1[0][sb] = offset_1[1][sb] =
offset * scalefactor;
scalefactor = adec_scalefactor_table[index_1];
slope_1[2][sb] = slope * scalefactor;
offset_1[2][sb] = offset * scalefactor;
}
break;
case 2:
index_0 = GetBits( &p_adec->bit_stream, 6 );
i_read_bits += 6;
if (allocation_1[sb] < 0)
{
slope_1[0][sb] = slope_1[1][sb] = slope_1[2][sb] =
adec_scalefactor_table[index_0];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_1[sb]-2];
offset = adec_offset_table[allocation_1[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_1[0][sb] = slope_1[1][sb] = slope_1[2][sb] =
slope * scalefactor;
offset_1[0][sb] = offset_1[1][sb] = offset_1[2][sb] =
offset * scalefactor;
}
break;
case 3:
index_0 = GetBits(&p_adec->bit_stream,6);
index_1 = GetBits(&p_adec->bit_stream,6);
i_read_bits += 12;
if (allocation_1[sb] < 0)
{
slope_1[0][sb] = adec_scalefactor_table[index_0];
slope_1[1][sb] = slope_1[2][sb] =
adec_scalefactor_table[index_1];
}
else
{
float scalefactor;
float slope, offset;
slope = adec_slope_table[allocation_1[sb]-2];
offset = adec_offset_table[allocation_1[sb]-2];
scalefactor = adec_scalefactor_table[index_0];
slope_1[0][sb] = slope * scalefactor;
offset_1[0][sb] = offset * scalefactor;
scalefactor = adec_scalefactor_table[index_1];
slope_1[1][sb] = slope_1[2][sb] = slope * scalefactor;
offset_1[1][sb] = offset_1[2][sb] =
offset * scalefactor;
}
break;
}
}
}
/* parse samples */
for (gr0 = 0; gr0 < 3; gr0++)
{
for (gr1 = 0; gr1 < 4; gr1++)
{
for (sb = 0; sb < bound; sb++)
{
int code;
switch (allocation_0[sb])
{
case 0:
sample_0[0][sb] = sample_0[1][sb] = sample_0[2][sb] = 0;
break;
case L3:
code = GetBits( &p_adec->bit_stream, 5 );
i_read_bits += 5;
sample_0[0][sb] = slope_0[gr0][sb] * L3_table[code % 3];
code /= 3;
sample_0[1][sb] = slope_0[gr0][sb] * L3_table[code % 3];
code /= 3;
sample_0[2][sb] = slope_0[gr0][sb] * L3_table[code];
break;
case L5:
code = GetBits( &p_adec->bit_stream, 7 );
i_read_bits += 7;
sample_0[0][sb] = slope_0[gr0][sb] * L5_table[code % 5];
code /= 5;
sample_0[1][sb] = slope_0[gr0][sb] * L5_table[code % 5];
code /= 5;
sample_0[2][sb] = slope_0[gr0][sb] * L5_table[code];
break;
case L9:
code = GetBits( &p_adec->bit_stream, 10 );
i_read_bits += 10;
sample_0[0][sb] = slope_0[gr0][sb] * L9_table[code % 9];
code /= 9;
sample_0[1][sb] = slope_0[gr0][sb] * L9_table[code % 9];
code /= 9;
sample_0[2][sb] = slope_0[gr0][sb] * L9_table[code];
break;
default:
for (s = 0; s < 3; s++)
{
code = GetBits( &p_adec->bit_stream,
allocation_0[sb] );
i_read_bits += allocation_0[sb];
sample_0[s][sb] =
slope_0[gr0][sb] * code + offset_0[gr0][sb];
}
}
switch (allocation_1[sb])
{
case 0:
sample_1[0][sb] = sample_1[1][sb] = sample_1[2][sb] = 0;
break;
case L3:
code = GetBits( &p_adec->bit_stream, 5 );
i_read_bits += 5;
sample_1[0][sb] = slope_1[gr0][sb] * L3_table[code % 3];
code /= 3;
sample_1[1][sb] = slope_1[gr0][sb] * L3_table[code % 3];
code /= 3;
sample_1[2][sb] = slope_1[gr0][sb] * L3_table[code];
break;
case L5:
code = GetBits( &p_adec->bit_stream, 7 );
i_read_bits += 7;
sample_1[0][sb] = slope_1[gr0][sb] * L5_table[code % 5];
code /= 5;
sample_1[1][sb] = slope_1[gr0][sb] * L5_table[code % 5];
code /= 5;
sample_1[2][sb] = slope_1[gr0][sb] * L5_table[code];
break;
case L9:
code = GetBits( &p_adec->bit_stream, 10 );
i_read_bits += 10;
sample_1[0][sb] = slope_1[gr0][sb] * L9_table[code % 9];
code /= 9;
sample_1[1][sb] = slope_1[gr0][sb] * L9_table[code % 9];
code /= 9;
sample_1[2][sb] = slope_1[gr0][sb] * L9_table[code];
break;
default:
for (s = 0; s < 3; s++)
{
code = GetBits( &p_adec->bit_stream,
allocation_1[sb] );
i_read_bits += allocation_1[sb];
sample_1[s][sb] =
slope_1[gr0][sb] * code + offset_1[gr0][sb];
}
}
}
for (; sb < sblimit; sb++)
{
int code;
switch (allocation_0[sb])
{
case 0:
sample_0[0][sb] = sample_0[1][sb] = sample_0[2][sb] = 0;
sample_1[0][sb] = sample_1[1][sb] = sample_1[2][sb] = 0;
break;
case L3:
code = GetBits( &p_adec->bit_stream, 5 );
i_read_bits += 5;
sample_0[0][sb] = slope_0[gr0][sb] * L3_table[code % 3];
sample_1[0][sb] = slope_1[gr0][sb] * L3_table[code % 3];
code /= 3;
sample_0[1][sb] = slope_0[gr0][sb] * L3_table[code % 3];
sample_1[1][sb] = slope_1[gr0][sb] * L3_table[code % 3];
code /= 3;
sample_0[2][sb] = slope_0[gr0][sb] * L3_table[code];
sample_1[2][sb] = slope_1[gr0][sb] * L3_table[code];
break;
case L5:
code = GetBits( &p_adec->bit_stream, 7 );
i_read_bits += 7;
sample_0[0][sb] = slope_0[gr0][sb] * L5_table[code % 5];
sample_1[0][sb] = slope_1[gr0][sb] * L5_table[code % 5];
code /= 5;
sample_0[1][sb] = slope_0[gr0][sb] * L5_table[code % 5];
sample_1[1][sb] = slope_1[gr0][sb] * L5_table[code % 5];
code /= 5;
sample_0[2][sb] = slope_0[gr0][sb] * L5_table[code];
sample_1[2][sb] = slope_1[gr0][sb] * L5_table[code];
break;
case L9:
code = GetBits( &p_adec->bit_stream, 10 );
i_read_bits += 10;
sample_0[0][sb] = slope_0[gr0][sb] * L9_table[code % 9];
sample_1[0][sb] = slope_1[gr0][sb] * L9_table[code % 9];
code /= 9;
sample_0[1][sb] = slope_0[gr0][sb] * L9_table[code % 9];
sample_1[1][sb] = slope_1[gr0][sb] * L9_table[code % 9];
code /= 9;
sample_0[2][sb] = slope_0[gr0][sb] * L9_table[code];
sample_1[2][sb] = slope_1[gr0][sb] * L9_table[code];
break;
default:
for (s = 0; s < 3; s++)
{
code = GetBits( &p_adec->bit_stream,
allocation_0[sb] );
i_read_bits += allocation_0[sb];
sample_0[s][sb] =
slope_0[gr0][sb] * code + offset_0[gr0][sb];
sample_1[s][sb] =
slope_1[gr0][sb] * code + offset_1[gr0][sb];
}
}
}
for (; sb < 32; sb++)
{
sample_0[0][sb] = sample_0[1][sb] = sample_0[2][sb] = 0;
sample_1[0][sb] = sample_1[1][sb] = sample_1[2][sb] = 0;
}
for (s = 0; s < 3; s++)
{
DCT32( &p_adec->bank_0, sample_0[s] );
PCM( &p_adec->bank_0, buffer, 2 );
DCT32( &p_adec->bank_1, sample_1[s] );
PCM( &p_adec->bank_1, buffer + 1, 2 );
buffer += 64;
}
}
}
p_adec->i_read_bits += i_read_bits;
return 0;
}