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|
/*
* most other tables are calculated on program start (which is (of course)
* not ISO-conform) ..
* Layer-3 huffman table is in huffman.h
*/
#include "mpeg3audio.h"
#include "../libmpeg3.h"
#include "../mpeg3protos.h"
#include "tables.h"
struct al_table alloc_0[] = {
{4,0},{5,3},{3,-3},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},{10,-511},
{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},{16,-32767},
{4,0},{5,3},{3,-3},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},{10,-511},
{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},{16,-32767},
{4,0},{5,3},{3,-3},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},{10,-511},
{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767} };
struct al_table alloc_1[] = {
{4,0},{5,3},{3,-3},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},{10,-511},
{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},{16,-32767},
{4,0},{5,3},{3,-3},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},{10,-511},
{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},{16,-32767},
{4,0},{5,3},{3,-3},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},{10,-511},
{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{3,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767},
{2,0},{5,3},{7,5},{16,-32767} };
struct al_table alloc_2[] = {
{4,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},
{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},
{4,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},
{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63} };
struct al_table alloc_3[] = {
{4,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},
{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},
{4,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},{9,-255},
{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},{15,-16383},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63} };
struct al_table alloc_4[] = {
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},
{4,0},{5,3},{7,5},{3,-3},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},{8,-127},
{9,-255},{10,-511},{11,-1023},{12,-2047},{13,-4095},{14,-8191},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{3,0},{5,3},{7,5},{10,9},{4,-7},{5,-15},{6,-31},{7,-63},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9},
{2,0},{5,3},{7,5},{10,9} };
int mpeg3audio_II_select_table(mpeg3audio_t *audio)
{
static int translate[3][2][16] =
{{{ 0,2,2,2,2,2,2,0,0,0,1,1,1,1,1,0},
{ 0,2,2,0,0,0,1,1,1,1,1,1,1,1,1,0}},
{{ 0,2,2,2,2,2,2,0,0,0,0,0,0,0,0,0},
{ 0,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0}},
{{ 0,3,3,3,3,3,3,0,0,0,1,1,1,1,1,0},
{ 0,3,3,0,0,0,1,1,1,1,1,1,1,1,1,0}}};
int table, sblim;
static struct al_table *tables[5] =
{alloc_0, alloc_1, alloc_2, alloc_3, alloc_4};
static int sblims[5] = {27, 30, 8, 12, 30};
if(audio->lsf)
table = 4;
else
table = translate[audio->sampling_frequency_code][2 - audio->channels][audio->bitrate_index];
sblim = sblims[table];
audio->alloc = tables[table];
audio->II_sblimit = sblim;
return 0;
}
int mpeg3audio_II_step_one(mpeg3audio_t *audio, unsigned int *bit_alloc, int *scale)
{
int stereo = audio->channels - 1;
int sblimit = audio->II_sblimit;
int jsbound = audio->jsbound;
int sblimit2 = audio->II_sblimit << stereo;
struct al_table *alloc1 = audio->alloc;
int i, result = 0;
unsigned int *scfsi_buf = audio->layer2_scfsi_buf;
unsigned int *scfsi, *bita;
int sc, step;
bita = bit_alloc;
if(stereo)
{
/* Stereo */
for(i = jsbound;i ; i--, alloc1 += (1 << step))
{
*bita++ = (char)mpeg3bits_getbits(audio->astream, step = alloc1->bits);
*bita++ = (char)mpeg3bits_getbits(audio->astream, step);
}
for(i = sblimit-jsbound; i; i--, alloc1 += (1 << step))
{
bita[0] = (char)mpeg3bits_getbits(audio->astream, step = alloc1->bits);
bita[1] = bita[0];
bita += 2;
}
bita = bit_alloc;
scfsi = scfsi_buf;
for(i = sblimit2; i; i--)
if(*bita++) *scfsi++ = (char)mpeg3bits_getbits(audio->astream, 2);
}
else
{
/* mono */
for(i = sblimit; i; i--, alloc1 += (1 << step))
*bita++ = (char)mpeg3bits_getbits(audio->astream, step = alloc1->bits);
bita = bit_alloc;
scfsi = scfsi_buf;
for(i = sblimit; i; i--) if (*bita++) *scfsi++ = (char)mpeg3bits_getbits(audio->astream, 2);
}
bita = bit_alloc;
scfsi = scfsi_buf;
for(i = sblimit2; i; i--)
{
if(*bita++)
switch(*scfsi++)
{
case 0:
*scale++ = mpeg3bits_getbits(audio->astream, 6);
*scale++ = mpeg3bits_getbits(audio->astream, 6);
*scale++ = mpeg3bits_getbits(audio->astream, 6);
break;
case 1 :
*scale++ = sc = mpeg3bits_getbits(audio->astream, 6);
*scale++ = sc;
*scale++ = mpeg3bits_getbits(audio->astream, 6);
break;
case 2:
*scale++ = sc = mpeg3bits_getbits(audio->astream, 6);
*scale++ = sc;
*scale++ = sc;
break;
default: /* case 3 */
*scale++ = mpeg3bits_getbits(audio->astream, 6);
*scale++ = sc = mpeg3bits_getbits(audio->astream, 6);
*scale++ = sc;
break;
}
}
return result | mpeg3bits_error(audio->astream);
}
int mpeg3audio_II_step_two(mpeg3audio_t *audio, unsigned int *bit_alloc, mpeg3_real_t fraction[2][4][SBLIMIT], int *scale, int x1)
{
int i, j, k, ba, result = 0;
int channels = audio->channels;
int sblimit = audio->II_sblimit;
int jsbound = audio->jsbound;
struct al_table *alloc2, *alloc1 = audio->alloc;
unsigned int *bita = bit_alloc;
int d1, step, test;
for(i = 0; i < jsbound; i++, alloc1 += (1 << step))
{
step = alloc1->bits;
for(j = 0; j < channels; j++)
{
if(ba = *bita++)
{
k = (alloc2 = alloc1 + ba)->bits;
if((d1 = alloc2->d) < 0)
{
mpeg3_real_t cm = mpeg3_muls[k][scale[x1]];
fraction[j][0][i] = ((mpeg3_real_t)((int)mpeg3bits_getbits(audio->astream, k) + d1)) * cm;
fraction[j][1][i] = ((mpeg3_real_t)((int)mpeg3bits_getbits(audio->astream, k) + d1)) * cm;
fraction[j][2][i] = ((mpeg3_real_t)((int)mpeg3bits_getbits(audio->astream, k) + d1)) * cm;
}
else
{
static int *table[] =
{0, 0, 0, mpeg3_grp_3tab, 0, mpeg3_grp_5tab, 0, 0, 0, mpeg3_grp_9tab};
unsigned int idx, *tab, m = scale[x1];
idx = (unsigned int)mpeg3bits_getbits(audio->astream, k);
tab = (unsigned int*)(table[d1] + idx + idx + idx);
fraction[j][0][i] = mpeg3_muls[*tab++][m];
fraction[j][1][i] = mpeg3_muls[*tab++][m];
fraction[j][2][i] = mpeg3_muls[*tab][m];
}
scale += 3;
}
else
fraction[j][0][i] = fraction[j][1][i] = fraction[j][2][i] = 0.0;
}
}
for(i = jsbound; i < sblimit; i++, alloc1 += (1 << step))
{
step = alloc1->bits;
/* channel 1 and channel 2 bitalloc are the same */
bita++;
if((ba = *bita++))
{
k=(alloc2 = alloc1+ba)->bits;
if((d1 = alloc2->d) < 0)
{
mpeg3_real_t cm;
cm = mpeg3_muls[k][scale[x1 + 3]];
fraction[1][0][i] = (fraction[0][0][i] = (mpeg3_real_t)((int)mpeg3bits_getbits(audio->astream, k) + d1)) * cm;
fraction[1][1][i] = (fraction[0][1][i] = (mpeg3_real_t)((int)mpeg3bits_getbits(audio->astream, k) + d1)) * cm;
fraction[1][2][i] = (fraction[0][2][i] = (mpeg3_real_t)((int)mpeg3bits_getbits(audio->astream, k) + d1)) * cm;
cm = mpeg3_muls[k][scale[x1]];
fraction[0][0][i] *= cm;
fraction[0][1][i] *= cm;
fraction[0][2][i] *= cm;
}
else
{
static int *table[] = {0, 0, 0, mpeg3_grp_3tab, 0, mpeg3_grp_5tab, 0, 0, 0, mpeg3_grp_9tab};
unsigned int idx, *tab, m1, m2;
m1 = scale[x1];
m2 = scale[x1+3];
idx = (unsigned int)mpeg3bits_getbits(audio->astream, k);
tab = (unsigned int*)(table[d1] + idx + idx + idx);
fraction[0][0][i] = mpeg3_muls[*tab][m1];
fraction[1][0][i] = mpeg3_muls[*tab++][m2];
fraction[0][1][i] = mpeg3_muls[*tab][m1];
fraction[1][1][i] = mpeg3_muls[*tab++][m2];
fraction[0][2][i] = mpeg3_muls[*tab][m1];
fraction[1][2][i] = mpeg3_muls[*tab][m2];
}
scale += 6;
}
else
{
fraction[0][0][i] = fraction[0][1][i] = fraction[0][2][i] =
fraction[1][0][i] = fraction[1][1][i] = fraction[1][2][i] = 0.0;
}
/*
should we use individual scalefac for channel 2 or
is the current way the right one , where we just copy channel 1 to
channel 2 ??
The current 'strange' thing is, that we throw away the scalefac
values for the second channel ...!!
-> changed .. now we use the scalefac values of channel one !!
*/
}
if(sblimit > SBLIMIT) sblimit = SBLIMIT;
for(i = sblimit; i < SBLIMIT; i++)
for(j = 0; j < channels; j++)
fraction[j][0][i] = fraction[j][1][i] = fraction[j][2][i] = 0.0;
return result | mpeg3bits_error(audio->astream);
}
int mpeg3audio_dolayer2(mpeg3audio_t *audio)
{
int i, j, result = 0;
int channels = audio->channels;
mpeg3_real_t fraction[2][4][SBLIMIT]; /* pick_table clears unused subbands */
unsigned int bit_alloc[64];
int scale[192];
int single = audio->single;
if(audio->error_protection)
mpeg3bits_getbits(audio->astream, 16);
mpeg3audio_II_select_table(audio);
audio->jsbound = (audio->mode == MPG_MD_JOINT_STEREO) ?
(audio->mode_ext << 2) + 4 : audio->II_sblimit;
if(channels == 1 || single == 3)
single = 0;
result |= mpeg3audio_II_step_one(audio, bit_alloc, scale);
for(i = 0; i < SCALE_BLOCK && !result; i++)
{
result |= mpeg3audio_II_step_two(audio, bit_alloc, fraction, scale, i >> 2);
for(j = 0; j < 3; j++)
{
if(single >= 0)
{
/* Monaural */
mpeg3audio_synth_mono(audio, fraction[single][j], audio->pcm_sample, &(audio->pcm_point));
}
else
{
/* Stereo */
int p1 = audio->pcm_point;
mpeg3audio_synth_stereo(audio, fraction[0][j], 0, audio->pcm_sample, &p1);
mpeg3audio_synth_stereo(audio, fraction[1][j], 1, audio->pcm_sample, &(audio->pcm_point));
}
if(audio->pcm_point / audio->channels >= audio->pcm_allocated - MPEG3AUDIO_PADDING * audio->channels)
{
/* Need more room */
mpeg3audio_replace_buffer(audio, audio->pcm_allocated + MPEG3AUDIO_PADDING * audio->channels);
}
}
}
return result;
}
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