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winamp/Src/external_dependencies/openmpt-trunk/include/lame/mpglib/layer2.c
Jef 20d28e80a5 Initial community commit
2024-09-24 14:54:57 +02:00

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/*
* layer2.c: Mpeg Layer-2 audio decoder
*
* Copyright (C) 1999-2010 The L.A.M.E. project
*
* Initially written by Michael Hipp, see also AUTHORS and README.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/* $Id: layer2.c,v 1.34 2017/08/22 23:31:07 robert Exp $ */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "common.h"
#include "layer2.h"
#include "l2tables.h"
#include "decode_i386.h"
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif
#include <assert.h>
static int gd_are_hip_tables_layer2_initialized = 0;
static unsigned char grp_3tab[32 * 3] = { 0, }; /* used: 27 */
static unsigned char grp_5tab[128 * 3] = { 0, }; /* used: 125 */
static unsigned char grp_9tab[1024 * 3] = { 0, }; /* used: 729 */
void
hip_init_tables_layer2(void)
{
static const double mulmul[27] = {
0.0, -2.0 / 3.0, 2.0 / 3.0,
2.0 / 7.0, 2.0 / 15.0, 2.0 / 31.0, 2.0 / 63.0, 2.0 / 127.0, 2.0 / 255.0,
2.0 / 511.0, 2.0 / 1023.0, 2.0 / 2047.0, 2.0 / 4095.0, 2.0 / 8191.0,
2.0 / 16383.0, 2.0 / 32767.0, 2.0 / 65535.0,
-4.0 / 5.0, -2.0 / 5.0, 2.0 / 5.0, 4.0 / 5.0,
-8.0 / 9.0, -4.0 / 9.0, -2.0 / 9.0, 2.0 / 9.0, 4.0 / 9.0, 8.0 / 9.0
};
static const unsigned char base[3][9] = {
{1, 0, 2,},
{17, 18, 0, 19, 20,},
{21, 1, 22, 23, 0, 24, 25, 2, 26}
};
int i, j, k, l, len;
real *table;
static const int tablen[3] = { 3, 5, 9 };
static unsigned char *itable, *tables[3] = { grp_3tab, grp_5tab, grp_9tab };
if (gd_are_hip_tables_layer2_initialized) {
return;
}
gd_are_hip_tables_layer2_initialized = 1;
for (i = 0; i < 3; i++) {
itable = tables[i];
len = tablen[i];
for (j = 0; j < len; j++)
for (k = 0; k < len; k++)
for (l = 0; l < len; l++) {
*itable++ = base[i][l];
*itable++ = base[i][k];
*itable++ = base[i][j];
}
}
for (k = 0; k < 27; k++) {
double m = mulmul[k];
table = muls[k];
for (j = 3, i = 0; i < 63; i++, j--)
*table++ = (real) (m * pow(2.0, (double) j / 3.0));
*table++ = 0.0;
}
}
static unsigned char*
grp_table_select(short d1, unsigned int idx)
{
/* RH: it seems to be common, that idx is larger than the table's sizes.
is it OK to return a zero vector in this case? FIXME
/*/
static unsigned char dummy_table[] = { 0,0,0 };
unsigned int x;
switch (d1) {
case 3:
x = 3*3*3;
idx = idx < x ? idx : x;
return &grp_3tab[3 * idx];
case 5:
x = 5*5*5;
idx = idx < x ? idx : x;
return &grp_5tab[3 * idx];
case 9:
x = 9*9*9;
idx = idx < x ? idx : x;
return &grp_9tab[3 * idx];
default:
/* fatal error */
assert(0);
}
return &dummy_table[0];
}
typedef struct sideinfo_layer_II_struct
{
unsigned char allocation[SBLIMIT][2];
unsigned char scalefactor[SBLIMIT][2][3]; /* subband / channel / block */
} sideinfo_layer_II;
static void
II_step_one(PMPSTR mp, sideinfo_layer_II *si, struct frame *fr)
{
int nch = fr->stereo;
int sblimit = fr->II_sblimit;
int jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ? (fr->mode_ext << 2) + 4 : fr->II_sblimit;
struct al_table2 const *alloc1 = fr->alloc;
unsigned char scfsi[SBLIMIT][2];
int i, ch;
memset(si, 0, sizeof(*si));
if (jsbound > sblimit)
jsbound = sblimit;
if (nch == 2) {
for (i = 0; i < jsbound; ++i) {
short step = alloc1->bits;
unsigned char b0 = get_leq_8_bits(mp, step);
unsigned char b1 = get_leq_8_bits(mp, step);
alloc1 += ((size_t)1 << step);
si->allocation[i][0] = b0;
si->allocation[i][1] = b1;
}
for (i = jsbound; i < sblimit; ++i) {
short step = alloc1->bits;
unsigned char b0 = get_leq_8_bits(mp, step);
alloc1 += ((size_t)1 << step);
si->allocation[i][0] = b0;
si->allocation[i][1] = b0;
}
for (i = 0; i < sblimit; ++i) {
unsigned char n0 = si->allocation[i][0];
unsigned char n1 = si->allocation[i][1];
unsigned char b0 = n0 ? get_leq_8_bits(mp, 2) : 0;
unsigned char b1 = n1 ? get_leq_8_bits(mp, 2) : 0;
scfsi[i][0] = b0;
scfsi[i][1] = b1;
}
}
else { /* mono */
for (i = 0; i < sblimit; ++i) {
short step = alloc1->bits;
unsigned char b0 = get_leq_8_bits(mp, step);
alloc1 += ((size_t)1 << step);
si->allocation[i][0] = b0;
}
for (i = 0; i < sblimit; ++i) {
unsigned char n0 = si->allocation[i][0];
unsigned char b0 = n0 ? get_leq_8_bits(mp, 2) : 0;
scfsi[i][0] = b0;
}
}
for (i = 0; i < sblimit; ++i) {
for (ch = 0; ch < nch; ++ch) {
unsigned char s0 = 0, s1 = 0, s2 = 0;
if (si->allocation[i][ch]) {
switch (scfsi[i][ch]) {
case 0:
s0 = get_leq_8_bits(mp, 6);
s1 = get_leq_8_bits(mp, 6);
s2 = get_leq_8_bits(mp, 6);
break;
case 1:
s0 = get_leq_8_bits(mp, 6);
s1 = s0;
s2 = get_leq_8_bits(mp, 6);
break;
case 2:
s0 = get_leq_8_bits(mp, 6);
s1 = s0;
s2 = s0;
break;
case 3:
s0 = get_leq_8_bits(mp, 6);
s1 = get_leq_8_bits(mp, 6);
s2 = s1;
break;
default:
assert(0);
}
}
si->scalefactor[i][ch][0] = s0;
si->scalefactor[i][ch][1] = s1;
si->scalefactor[i][ch][2] = s2;
}
}
}
static void
II_step_two(PMPSTR mp, sideinfo_layer_II* si, struct frame *fr, int gr, real fraction[2][4][SBLIMIT])
{
struct al_table2 const *alloc1 = fr->alloc;
int sblimit = fr->II_sblimit;
int jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ? (fr->mode_ext << 2) + 4 : fr->II_sblimit;
int i, ch, nch = fr->stereo;
double cm, r0, r1, r2;
if (jsbound > sblimit)
jsbound = sblimit;
for (i = 0; i < jsbound; ++i) {
short step = alloc1->bits;
for (ch = 0; ch < nch; ++ch) {
unsigned char ba = si->allocation[i][ch];
if (ba) {
unsigned char x1 = si->scalefactor[i][ch][gr];
struct al_table2 const *alloc2 = alloc1 + ba;
short k = alloc2->bits;
short d1 = alloc2->d;
assert( k <= 16 );
k = (k <= 16) ? k : 16;
assert( x1 < 64 );
x1 = (x1 < 64) ? x1 : 63;
if (d1 < 0) {
int v0 = getbits(mp, k);
int v1 = getbits(mp, k);
int v2 = getbits(mp, k);
cm = muls[k][x1];
r0 = (v0 + d1) * cm;
r1 = (v1 + d1) * cm;
r2 = (v2 + d1) * cm;
}
else {
unsigned int idx = getbits(mp, k);
unsigned char *tab = grp_table_select(d1, idx);
unsigned char k0 = tab[0];
unsigned char k1 = tab[1];
unsigned char k2 = tab[2];
r0 = muls[k0][x1];
r1 = muls[k1][x1];
r2 = muls[k2][x1];
}
fraction[ch][0][i] = (real) r0;
fraction[ch][1][i] = (real) r1;
fraction[ch][2][i] = (real) r2;
}
else {
fraction[ch][0][i] = fraction[ch][1][i] = fraction[ch][2][i] = 0.0;
}
}
alloc1 += ((size_t)1 << step);
}
for (i = jsbound; i < sblimit; i++) {
short step = alloc1->bits;
unsigned char ba = si->allocation[i][0];
if (ba) {
struct al_table2 const *alloc2 = alloc1 + ba;
short k = alloc2->bits;
short d1 = alloc2->d;
assert( k <= 16 );
k = (k <= 16) ? k : 16;
if (d1 < 0) {
int v0 = getbits(mp, k);
int v1 = getbits(mp, k);
int v2 = getbits(mp, k);
for (ch = 0; ch < nch; ++ch) {
unsigned char x1 = si->scalefactor[i][ch][gr];
assert( x1 < 64 );
x1 = (x1 < 64) ? x1 : 63;
cm = muls[k][x1];
r0 = (v0 + d1) * cm;
r1 = (v1 + d1) * cm;
r2 = (v2 + d1) * cm;
fraction[ch][0][i] = (real) r0;
fraction[ch][1][i] = (real) r1;
fraction[ch][2][i] = (real) r2;
}
}
else {
unsigned int idx = getbits(mp, k);
unsigned char *tab = grp_table_select(d1, idx);
unsigned char k0 = tab[0];
unsigned char k1 = tab[1];
unsigned char k2 = tab[2];
for (ch = 0; ch < nch; ++ch) {
unsigned char x1 = si->scalefactor[i][ch][gr];
assert( x1 < 64 );
x1 = (x1 < 64) ? x1 : 63;
r0 = muls[k0][x1];
r1 = muls[k1][x1];
r2 = muls[k2][x1];
fraction[ch][0][i] = (real) r0;
fraction[ch][1][i] = (real) r1;
fraction[ch][2][i] = (real) r2;
}
}
}
else {
fraction[0][0][i] = fraction[0][1][i] = fraction[0][2][i] = 0.0;
fraction[1][0][i] = fraction[1][1][i] = fraction[1][2][i] = 0.0;
}
alloc1 += ((size_t)1 << step);
}
if (sblimit > fr->down_sample_sblimit) {
sblimit = fr->down_sample_sblimit;
}
for (ch = 0; ch < nch; ++ch) {
for (i = sblimit; i < SBLIMIT; ++i) {
fraction[ch][0][i] = fraction[ch][1][i] = fraction[ch][2][i] = 0.0;
}
}
}
static void
II_select_table(struct frame *fr)
{
/* *INDENT-OFF* */
static const 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 } } };
/* *INDENT-ON* */
int table, sblim;
static const struct al_table2 *tables[5] = { alloc_0, alloc_1, alloc_2, alloc_3, alloc_4 };
static const int sblims[5] = { 27, 30, 8, 12, 30 };
if (fr->lsf)
table = 4;
else
table = translate[fr->sampling_frequency][2 - fr->stereo][fr->bitrate_index];
sblim = sblims[table];
fr->alloc = (struct al_table2 const *) tables[table];
fr->II_sblimit = sblim;
}
int
decode_layer2_sideinfo(PMPSTR mp)
{
(void) mp;
/* FIXME: extract side information and check values */
return 0;
}
int
decode_layer2_frame(PMPSTR mp, unsigned char *pcm_sample, int *pcm_point)
{
real fraction[2][4][SBLIMIT]; /* pick_table clears unused subbands */
sideinfo_layer_II si;
struct frame *fr = &(mp->fr);
int single = fr->single;
int i, j, clip = 0;
II_select_table(fr);
II_step_one(mp, &si, fr);
if (fr->stereo == 1 || single == 3)
single = 0;
if (single >= 0) {
for (i = 0; i < SCALE_BLOCK; i++) {
II_step_two(mp, &si, fr, i >> 2, fraction);
for (j = 0; j < 3; j++) {
clip += synth_1to1_mono(mp, fraction[single][j], pcm_sample, pcm_point);
}
}
}
else {
for (i = 0; i < SCALE_BLOCK; i++) {
II_step_two(mp, &si, fr, i >> 2, fraction);
for (j = 0; j < 3; j++) {
int p1 = *pcm_point;
clip += synth_1to1(mp, fraction[0][j], 0, pcm_sample, &p1);
clip += synth_1to1(mp, fraction[1][j], 1, pcm_sample, pcm_point);
}
}
}
return clip;
}
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