blob: 822228edbde3f81be1a2a2ee715bedc3267b40fb [file] [log] [blame]
/*
* MPEG Audio decoder
* Copyright (c) 2001, 2002 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file libavcodec/mpegaudiodec.c
* MPEG Audio decoder.
*/
#include "avcodec.h"
#include "bitstream.h"
#include "dsputil.h"
/*
* TODO:
* - in low precision mode, use more 16 bit multiplies in synth filter
* - test lsf / mpeg25 extensively.
*/
#include "mpegaudio.h"
#include "mpegaudiodecheader.h"
#include "mathops.h"
/* WARNING: only correct for posititive numbers */
#define FIXR(a) ((int)((a) * FRAC_ONE + 0.5))
#define FRAC_RND(a) (((a) + (FRAC_ONE/2)) >> FRAC_BITS)
#define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5))
/****************/
#define HEADER_SIZE 4
/* layer 3 "granule" */
typedef struct GranuleDef {
uint8_t scfsi;
int part2_3_length;
int big_values;
int global_gain;
int scalefac_compress;
uint8_t block_type;
uint8_t switch_point;
int table_select[3];
int subblock_gain[3];
uint8_t scalefac_scale;
uint8_t count1table_select;
int region_size[3]; /* number of huffman codes in each region */
int preflag;
int short_start, long_end; /* long/short band indexes */
uint8_t scale_factors[40];
int32_t sb_hybrid[SBLIMIT * 18]; /* 576 samples */
} GranuleDef;
#include "mpegaudiodata.h"
#include "mpegaudiodectab.h"
static void compute_antialias_integer(MPADecodeContext *s, GranuleDef *g);
static void compute_antialias_float(MPADecodeContext *s, GranuleDef *g);
/* vlc structure for decoding layer 3 huffman tables */
static VLC huff_vlc[16];
static VLC_TYPE huff_vlc_tables[
0+128+128+128+130+128+154+166+
142+204+190+170+542+460+662+414
][2];
static const int huff_vlc_tables_sizes[16] = {
0, 128, 128, 128, 130, 128, 154, 166,
142, 204, 190, 170, 542, 460, 662, 414
};
static VLC huff_quad_vlc[2];
static VLC_TYPE huff_quad_vlc_tables[128+16][2];
static const int huff_quad_vlc_tables_sizes[2] = {
128, 16
};
/* computed from band_size_long */
static uint16_t band_index_long[9][23];
/* XXX: free when all decoders are closed */
#define TABLE_4_3_SIZE (8191 + 16)*4
#ifdef EM8622
#include "mp3table.h"
#else
static int8_t table_4_3_exp[TABLE_4_3_SIZE];
static uint32_t table_4_3_value[TABLE_4_3_SIZE];
static uint32_t exp_table[512];
static uint32_t expval_table[512][16];
#endif
/* intensity stereo coef table */
static int32_t is_table[2][16];
static int32_t is_table_lsf[2][2][16];
static int32_t csa_table[8][4];
static float csa_table_float[8][4];
static int32_t mdct_win[8][36];
/* lower 2 bits: modulo 3, higher bits: shift */
static uint16_t scale_factor_modshift[64];
/* [i][j]: 2^(-j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2) - 1) */
static int32_t scale_factor_mult[15][3];
/* mult table for layer 2 group quantization */
#define SCALE_GEN(v) \
{ FIXR(1.0 * (v)), FIXR(0.7937005259 * (v)), FIXR(0.6299605249 * (v)) }
static const int32_t scale_factor_mult2[3][3] = {
SCALE_GEN(4.0 / 3.0), /* 3 steps */
SCALE_GEN(4.0 / 5.0), /* 5 steps */
SCALE_GEN(4.0 / 9.0), /* 9 steps */
};
static DECLARE_ALIGNED_16(MPA_INT, window[512]);
/**
* Convert region offsets to region sizes and truncate
* size to big_values.
*/
void ff_region_offset2size(GranuleDef *g){
int i, k, j=0;
g->region_size[2] = (576 / 2);
for(i=0;i<3;i++) {
k = FFMIN(g->region_size[i], g->big_values);
g->region_size[i] = k - j;
j = k;
}
}
void ff_init_short_region(MPADecodeContext *s, GranuleDef *g){
if (g->block_type == 2)
g->region_size[0] = (36 / 2);
else {
if (s->sample_rate_index <= 2)
g->region_size[0] = (36 / 2);
else if (s->sample_rate_index != 8)
g->region_size[0] = (54 / 2);
else
g->region_size[0] = (108 / 2);
}
g->region_size[1] = (576 / 2);
}
void ff_init_long_region(MPADecodeContext *s, GranuleDef *g, int ra1, int ra2){
int l;
g->region_size[0] =
band_index_long[s->sample_rate_index][ra1 + 1] >> 1;
/* should not overflow */
l = FFMIN(ra1 + ra2 + 2, 22);
g->region_size[1] =
band_index_long[s->sample_rate_index][l] >> 1;
}
void ff_compute_band_indexes(MPADecodeContext *s, GranuleDef *g){
if (g->block_type == 2) {
if (g->switch_point) {
/* if switched mode, we handle the 36 first samples as
long blocks. For 8000Hz, we handle the 48 first
exponents as long blocks (XXX: check this!) */
if (s->sample_rate_index <= 2)
g->long_end = 8;
else if (s->sample_rate_index != 8)
g->long_end = 6;
else
g->long_end = 4; /* 8000 Hz */
g->short_start = 2 + (s->sample_rate_index != 8);
} else {
g->long_end = 0;
g->short_start = 0;
}
} else {
g->short_start = 13;
g->long_end = 22;
}
}
/* layer 1 unscaling */
/* n = number of bits of the mantissa minus 1 */
static inline int l1_unscale(int n, int mant, int scale_factor)
{
int shift, mod;
int64_t val;
shift = scale_factor_modshift[scale_factor];
mod = shift & 3;
shift >>= 2;
val = MUL64(mant + (-1 << n) + 1, scale_factor_mult[n-1][mod]);
shift += n;
/* NOTE: at this point, 1 <= shift >= 21 + 15 */
return (int)((val + (1LL << (shift - 1))) >> shift);
}
static inline int l2_unscale_group(int steps, int mant, int scale_factor)
{
int shift, mod, val;
shift = scale_factor_modshift[scale_factor];
mod = shift & 3;
shift >>= 2;
val = (mant - (steps >> 1)) * scale_factor_mult2[steps >> 2][mod];
/* NOTE: at this point, 0 <= shift <= 21 */
if (shift > 0)
val = (val + (1 << (shift - 1))) >> shift;
return val;
}
/* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */
static inline int l3_unscale(int value, int exponent)
{
unsigned int m;
int e;
e = table_4_3_exp [4*value + (exponent&3)];
m = table_4_3_value[4*value + (exponent&3)];
e -= (exponent >> 2);
assert(e>=1);
if (e > 31)
return 0;
m = (m + (1 << (e-1))) >> e;
return m;
}
/* all integer n^(4/3) computation code */
#define DEV_ORDER 13
#define POW_FRAC_BITS 24
#define POW_FRAC_ONE (1 << POW_FRAC_BITS)
#define POW_FIX(a) ((int)((a) * POW_FRAC_ONE))
#define POW_MULL(a,b) (((int64_t)(a) * (int64_t)(b)) >> POW_FRAC_BITS)
static int dev_4_3_coefs[DEV_ORDER];
#if 0 /* unused */
static int pow_mult3[3] = {
POW_FIX(1.0),
POW_FIX(1.25992104989487316476),
POW_FIX(1.58740105196819947474),
};
#endif
static av_cold void int_pow_init(void)
{
int i, a;
a = POW_FIX(1.0);
for(i=0;i<DEV_ORDER;i++) {
a = POW_MULL(a, POW_FIX(4.0 / 3.0) - i * POW_FIX(1.0)) / (i + 1);
dev_4_3_coefs[i] = a;
}
}
#if 0 /* unused, remove? */
/* return the mantissa and the binary exponent */
static int int_pow(int i, int *exp_ptr)
{
int e, er, eq, j;
int a, a1;
/* renormalize */
a = i;
e = POW_FRAC_BITS;
while (a < (1 << (POW_FRAC_BITS - 1))) {
a = a << 1;
e--;
}
a -= (1 << POW_FRAC_BITS);
a1 = 0;
for(j = DEV_ORDER - 1; j >= 0; j--)
a1 = POW_MULL(a, dev_4_3_coefs[j] + a1);
a = (1 << POW_FRAC_BITS) + a1;
/* exponent compute (exact) */
e = e * 4;
er = e % 3;
eq = e / 3;
a = POW_MULL(a, pow_mult3[er]);
while (a >= 2 * POW_FRAC_ONE) {
a = a >> 1;
eq++;
}
/* convert to float */
while (a < POW_FRAC_ONE) {
a = a << 1;
eq--;
}
/* now POW_FRAC_ONE <= a < 2 * POW_FRAC_ONE */
#if POW_FRAC_BITS > FRAC_BITS
a = (a + (1 << (POW_FRAC_BITS - FRAC_BITS - 1))) >> (POW_FRAC_BITS - FRAC_BITS);
/* correct overflow */
if (a >= 2 * (1 << FRAC_BITS)) {
a = a >> 1;
eq++;
}
#endif
*exp_ptr = eq;
return a;
}
#endif
#ifdef EM8622
#include <sys/time.h>
static long long inittime=0;
static long long get_timebase()
{
struct timeval tm;
gettimeofday(&tm, 0);
return tm.tv_sec * 1000000LL + (tm.tv_usec);
}
#endif
static av_cold int decode_init(AVCodecContext * avctx)
{
MPADecodeContext *s = avctx->priv_data;
static int init=0;
int i, j, k;
#ifdef EM8622
long long startinittime = get_timebase();
#endif
s->avctx = avctx;
avctx->sample_fmt= OUT_FMT;
s->error_recognition= avctx->error_recognition;
if(avctx->antialias_algo != FF_AA_FLOAT)
s->compute_antialias= compute_antialias_integer;
else
s->compute_antialias= compute_antialias_float;
if (!init && !avctx->parse_only) {
int offset;
/* scale factors table for layer 1/2 */
for(i=0;i<64;i++) {
int shift, mod;
/* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */
shift = (i / 3);
mod = i % 3;
scale_factor_modshift[i] = mod | (shift << 2);
}
/* scale factor multiply for layer 1 */
for(i=0;i<15;i++) {
int n, norm;
n = i + 2;
norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n) - 1);
scale_factor_mult[i][0] = MULL(FIXR(1.0 * 2.0), norm, FRAC_BITS);
scale_factor_mult[i][1] = MULL(FIXR(0.7937005259 * 2.0), norm, FRAC_BITS);
scale_factor_mult[i][2] = MULL(FIXR(0.6299605249 * 2.0), norm, FRAC_BITS);
dprintf(avctx, "%d: norm=%x s=%x %x %x\n",
i, norm,
scale_factor_mult[i][0],
scale_factor_mult[i][1],
scale_factor_mult[i][2]);
}
ff_mpa_synth_init(window);
/* huffman decode tables */
offset = 0;
for(i=1;i<16;i++) {
const HuffTable *h = &mpa_huff_tables[i];
int xsize, x, y;
unsigned int n;
uint8_t tmp_bits [512];
uint16_t tmp_codes[512];
memset(tmp_bits , 0, sizeof(tmp_bits ));
memset(tmp_codes, 0, sizeof(tmp_codes));
xsize = h->xsize;
n = xsize * xsize;
j = 0;
for(x=0;x<xsize;x++) {
for(y=0;y<xsize;y++){
tmp_bits [(x << 5) | y | ((x&&y)<<4)]= h->bits [j ];
tmp_codes[(x << 5) | y | ((x&&y)<<4)]= h->codes[j++];
}
}
/* XXX: fail test */
huff_vlc[i].table = huff_vlc_tables+offset;
huff_vlc[i].table_allocated = huff_vlc_tables_sizes[i];
init_vlc(&huff_vlc[i], 7, 512,
tmp_bits, 1, 1, tmp_codes, 2, 2,
INIT_VLC_USE_NEW_STATIC);
offset += huff_vlc_tables_sizes[i];
}
assert(offset == FF_ARRAY_ELEMS(huff_vlc_tables));
offset = 0;
for(i=0;i<2;i++) {
huff_quad_vlc[i].table = huff_quad_vlc_tables+offset;
huff_quad_vlc[i].table_allocated = huff_quad_vlc_tables_sizes[i];
init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16,
mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1,
INIT_VLC_USE_NEW_STATIC);
offset += huff_quad_vlc_tables_sizes[i];
}
assert(offset == FF_ARRAY_ELEMS(huff_quad_vlc_tables));
for(i=0;i<9;i++) {
k = 0;
for(j=0;j<22;j++) {
band_index_long[i][j] = k;
k += band_size_long[i][j];
}
band_index_long[i][22] = k;
}
/* compute n ^ (4/3) and store it in mantissa/exp format */
int_pow_init();
#ifndef EM8622
for(i=1;i<TABLE_4_3_SIZE;i++) {
double f, fm;
int e, m;
f = pow((double)(i/4), 4.0 / 3.0) * pow(2, (i&3)*0.25);
fm = frexp(f, &e);
m = (uint32_t)(fm*(1LL<<31) + 0.5);
e+= FRAC_BITS - 31 + 5 - 100;
/* normalized to FRAC_BITS */
table_4_3_value[i] = m;
table_4_3_exp[i] = -e;
}
for(i=0; i<512*16; i++){
int exponent= (i>>4);
double f= pow(i&15, 4.0 / 3.0) * pow(2, (exponent-400)*0.25 + FRAC_BITS + 5);
expval_table[exponent][i&15]= llrint(f);
if((i&15)==1)
exp_table[exponent]= llrint(f);
}
#else
// Linking problem...
{
double f, fm;
int e, m;
f=1.0f;
fm = frexp(f, &e);
}
#endif
for(i=0;i<7;i++) {
float f;
int v;
if (i != 6) {
f = tan((double)i * M_PI / 12.0);
v = FIXR(f / (1.0 + f));
} else {
v = FIXR(1.0);
}
is_table[0][i] = v;
is_table[1][6 - i] = v;
}
/* invalid values */
for(i=7;i<16;i++)
is_table[0][i] = is_table[1][i] = 0.0;
for(i=0;i<16;i++) {
double f;
int e, k;
for(j=0;j<2;j++) {
e = -(j + 1) * ((i + 1) >> 1);
f = pow(2.0, e / 4.0);
k = i & 1;
is_table_lsf[j][k ^ 1][i] = FIXR(f);
is_table_lsf[j][k][i] = FIXR(1.0);
dprintf(avctx, "is_table_lsf %d %d: %x %x\n",
i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]);
}
}
for(i=0;i<8;i++) {
float ci, cs, ca;
ci = ci_table[i];
cs = 1.0 / sqrt(1.0 + ci * ci);
ca = cs * ci;
csa_table[i][0] = FIXHR(cs/4);
csa_table[i][1] = FIXHR(ca/4);
csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4);
csa_table[i][3] = FIXHR(ca/4) - FIXHR(cs/4);
csa_table_float[i][0] = cs;
csa_table_float[i][1] = ca;
csa_table_float[i][2] = ca + cs;
csa_table_float[i][3] = ca - cs;
}
/* compute mdct windows */
for(i=0;i<36;i++) {
for(j=0; j<4; j++){
double d;
if(j==2 && i%3 != 1)
continue;
d= sin(M_PI * (i + 0.5) / 36.0);
if(j==1){
if (i>=30) d= 0;
else if(i>=24) d= sin(M_PI * (i - 18 + 0.5) / 12.0);
else if(i>=18) d= 1;
}else if(j==3){
if (i< 6) d= 0;
else if(i< 12) d= sin(M_PI * (i - 6 + 0.5) / 12.0);
else if(i< 18) d= 1;
}
//merge last stage of imdct into the window coefficients
d*= 0.5 / cos(M_PI*(2*i + 19)/72);
if(j==2)
mdct_win[j][i/3] = FIXHR((d / (1<<5)));
else
mdct_win[j][i ] = FIXHR((d / (1<<5)));
}
}
/* NOTE: we do frequency inversion adter the MDCT by changing
the sign of the right window coefs */
for(j=0;j<4;j++) {
for(i=0;i<36;i+=2) {
mdct_win[j + 4][i] = mdct_win[j][i];
mdct_win[j + 4][i + 1] = -mdct_win[j][i + 1];
}
}
init = 1;
#ifdef EM8622
#undef fprintf
fprintf(stderr,"mp3 init time %lld\n",get_timebase()-startinittime);
#endif
}
if (avctx->codec_id == CODEC_ID_MP3ADU)
s->adu_mode = 1;
return 0;
}
/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6 - j))) */
/* cos(i*pi/64) */
#define COS0_0 FIXHR(0.50060299823519630134/2)
#define COS0_1 FIXHR(0.50547095989754365998/2)
#define COS0_2 FIXHR(0.51544730992262454697/2)
#define COS0_3 FIXHR(0.53104259108978417447/2)
#define COS0_4 FIXHR(0.55310389603444452782/2)
#define COS0_5 FIXHR(0.58293496820613387367/2)
#define COS0_6 FIXHR(0.62250412303566481615/2)
#define COS0_7 FIXHR(0.67480834145500574602/2)
#define COS0_8 FIXHR(0.74453627100229844977/2)
#define COS0_9 FIXHR(0.83934964541552703873/2)
#define COS0_10 FIXHR(0.97256823786196069369/2)
#define COS0_11 FIXHR(1.16943993343288495515/4)
#define COS0_12 FIXHR(1.48416461631416627724/4)
#define COS0_13 FIXHR(2.05778100995341155085/8)
#define COS0_14 FIXHR(3.40760841846871878570/8)
#define COS0_15 FIXHR(10.19000812354805681150/32)
#define COS1_0 FIXHR(0.50241928618815570551/2)
#define COS1_1 FIXHR(0.52249861493968888062/2)
#define COS1_2 FIXHR(0.56694403481635770368/2)
#define COS1_3 FIXHR(0.64682178335999012954/2)
#define COS1_4 FIXHR(0.78815462345125022473/2)
#define COS1_5 FIXHR(1.06067768599034747134/4)
#define COS1_6 FIXHR(1.72244709823833392782/4)
#define COS1_7 FIXHR(5.10114861868916385802/16)
#define COS2_0 FIXHR(0.50979557910415916894/2)
#define COS2_1 FIXHR(0.60134488693504528054/2)
#define COS2_2 FIXHR(0.89997622313641570463/2)
#define COS2_3 FIXHR(2.56291544774150617881/8)
#define COS3_0 FIXHR(0.54119610014619698439/2)
#define COS3_1 FIXHR(1.30656296487637652785/4)
#define COS4_0 FIXHR(0.70710678118654752439/2)
/* butterfly operator */
#define BF(a, b, c, s)\
{\
tmp0 = tab[a] + tab[b];\
tmp1 = tab[a] - tab[b];\
tab[a] = tmp0;\
tab[b] = MULH(tmp1<<(s), c);\
}
#define BF1(a, b, c, d)\
{\
BF(a, b, COS4_0, 1);\
BF(c, d,-COS4_0, 1);\
tab[c] += tab[d];\
}
#define BF2(a, b, c, d)\
{\
BF(a, b, COS4_0, 1);\
BF(c, d,-COS4_0, 1);\
tab[c] += tab[d];\
tab[a] += tab[c];\
tab[c] += tab[b];\
tab[b] += tab[d];\
}
#define ADD(a, b) tab[a] += tab[b]
/* DCT32 without 1/sqrt(2) coef zero scaling. */
static void dct32(int32_t *out, int32_t *tab)
{
int tmp0, tmp1;
/* pass 1 */
BF( 0, 31, COS0_0 , 1);
BF(15, 16, COS0_15, 5);
/* pass 2 */
BF( 0, 15, COS1_0 , 1);
BF(16, 31,-COS1_0 , 1);
/* pass 1 */
BF( 7, 24, COS0_7 , 1);
BF( 8, 23, COS0_8 , 1);
/* pass 2 */
BF( 7, 8, COS1_7 , 4);
BF(23, 24,-COS1_7 , 4);
/* pass 3 */
BF( 0, 7, COS2_0 , 1);
BF( 8, 15,-COS2_0 , 1);
BF(16, 23, COS2_0 , 1);
BF(24, 31,-COS2_0 , 1);
/* pass 1 */
BF( 3, 28, COS0_3 , 1);
BF(12, 19, COS0_12, 2);
/* pass 2 */
BF( 3, 12, COS1_3 , 1);
BF(19, 28,-COS1_3 , 1);
/* pass 1 */
BF( 4, 27, COS0_4 , 1);
BF(11, 20, COS0_11, 2);
/* pass 2 */
BF( 4, 11, COS1_4 , 1);
BF(20, 27,-COS1_4 , 1);
/* pass 3 */
BF( 3, 4, COS2_3 , 3);
BF(11, 12,-COS2_3 , 3);
BF(19, 20, COS2_3 , 3);
BF(27, 28,-COS2_3 , 3);
/* pass 4 */
BF( 0, 3, COS3_0 , 1);
BF( 4, 7,-COS3_0 , 1);
BF( 8, 11, COS3_0 , 1);
BF(12, 15,-COS3_0 , 1);
BF(16, 19, COS3_0 , 1);
BF(20, 23,-COS3_0 , 1);
BF(24, 27, COS3_0 , 1);
BF(28, 31,-COS3_0 , 1);
/* pass 1 */
BF( 1, 30, COS0_1 , 1);
BF(14, 17, COS0_14, 3);
/* pass 2 */
BF( 1, 14, COS1_1 , 1);
BF(17, 30,-COS1_1 , 1);
/* pass 1 */
BF( 6, 25, COS0_6 , 1);
BF( 9, 22, COS0_9 , 1);
/* pass 2 */
BF( 6, 9, COS1_6 , 2);
BF(22, 25,-COS1_6 , 2);
/* pass 3 */
BF( 1, 6, COS2_1 , 1);
BF( 9, 14,-COS2_1 , 1);
BF(17, 22, COS2_1 , 1);
BF(25, 30,-COS2_1 , 1);
/* pass 1 */
BF( 2, 29, COS0_2 , 1);
BF(13, 18, COS0_13, 3);
/* pass 2 */
BF( 2, 13, COS1_2 , 1);
BF(18, 29,-COS1_2 , 1);
/* pass 1 */
BF( 5, 26, COS0_5 , 1);
BF(10, 21, COS0_10, 1);
/* pass 2 */
BF( 5, 10, COS1_5 , 2);
BF(21, 26,-COS1_5 , 2);
/* pass 3 */
BF( 2, 5, COS2_2 , 1);
BF(10, 13,-COS2_2 , 1);
BF(18, 21, COS2_2 , 1);
BF(26, 29,-COS2_2 , 1);
/* pass 4 */
BF( 1, 2, COS3_1 , 2);
BF( 5, 6,-COS3_1 , 2);
BF( 9, 10, COS3_1 , 2);
BF(13, 14,-COS3_1 , 2);
BF(17, 18, COS3_1 , 2);
BF(21, 22,-COS3_1 , 2);
BF(25, 26, COS3_1 , 2);
BF(29, 30,-COS3_1 , 2);
/* pass 5 */
BF1( 0, 1, 2, 3);
BF2( 4, 5, 6, 7);
BF1( 8, 9, 10, 11);
BF2(12, 13, 14, 15);
BF1(16, 17, 18, 19);
BF2(20, 21, 22, 23);
BF1(24, 25, 26, 27);
BF2(28, 29, 30, 31);
/* pass 6 */
ADD( 8, 12);
ADD(12, 10);
ADD(10, 14);
ADD(14, 9);
ADD( 9, 13);
ADD(13, 11);
ADD(11, 15);
out[ 0] = tab[0];
out[16] = tab[1];
out[ 8] = tab[2];
out[24] = tab[3];
out[ 4] = tab[4];
out[20] = tab[5];
out[12] = tab[6];
out[28] = tab[7];
out[ 2] = tab[8];
out[18] = tab[9];
out[10] = tab[10];
out[26] = tab[11];
out[ 6] = tab[12];
out[22] = tab[13];
out[14] = tab[14];
out[30] = tab[15];
ADD(24, 28);
ADD(28, 26);
ADD(26, 30);
ADD(30, 25);
ADD(25, 29);
ADD(29, 27);
ADD(27, 31);
out[ 1] = tab[16] + tab[24];
out[17] = tab[17] + tab[25];
out[ 9] = tab[18] + tab[26];
out[25] = tab[19] + tab[27];
out[ 5] = tab[20] + tab[28];
out[21] = tab[21] + tab[29];
out[13] = tab[22] + tab[30];
out[29] = tab[23] + tab[31];
out[ 3] = tab[24] + tab[20];
out[19] = tab[25] + tab[21];
out[11] = tab[26] + tab[22];
out[27] = tab[27] + tab[23];
out[ 7] = tab[28] + tab[18];
out[23] = tab[29] + tab[19];
out[15] = tab[30] + tab[17];
out[31] = tab[31];
}
#if FRAC_BITS <= 15
static inline int round_sample(int *sum)
{
int sum1;
sum1 = (*sum) >> OUT_SHIFT;
*sum &= (1<<OUT_SHIFT)-1;
if (sum1 < OUT_MIN)
sum1 = OUT_MIN;
else if (sum1 > OUT_MAX)
sum1 = OUT_MAX;
return sum1;
}
/* signed 16x16 -> 32 multiply add accumulate */
#define MACS(rt, ra, rb) MAC16(rt, ra, rb)
/* signed 16x16 -> 32 multiply */
#define MULS(ra, rb) MUL16(ra, rb)
#define MLSS(rt, ra, rb) MLS16(rt, ra, rb)
#else
static inline int round_sample(int64_t *sum)
{
int sum1;
sum1 = (int)((*sum) >> OUT_SHIFT);
*sum &= (1<<OUT_SHIFT)-1;
if (sum1 < OUT_MIN)
sum1 = OUT_MIN;
else if (sum1 > OUT_MAX)
sum1 = OUT_MAX;
return sum1;
}
# define MULS(ra, rb) MUL64(ra, rb)
# define MACS(rt, ra, rb) MAC64(rt, ra, rb)
# define MLSS(rt, ra, rb) MLS64(rt, ra, rb)
#endif
#define SUM8(op, sum, w, p) \
{ \
op(sum, (w)[0 * 64], p[0 * 64]); \
op(sum, (w)[1 * 64], p[1 * 64]); \
op(sum, (w)[2 * 64], p[2 * 64]); \
op(sum, (w)[3 * 64], p[3 * 64]); \
op(sum, (w)[4 * 64], p[4 * 64]); \
op(sum, (w)[5 * 64], p[5 * 64]); \
op(sum, (w)[6 * 64], p[6 * 64]); \
op(sum, (w)[7 * 64], p[7 * 64]); \
}
#define SUM8P2(sum1, op1, sum2, op2, w1, w2, p) \
{ \
int tmp;\
tmp = p[0 * 64];\
op1(sum1, (w1)[0 * 64], tmp);\
op2(sum2, (w2)[0 * 64], tmp);\
tmp = p[1 * 64];\
op1(sum1, (w1)[1 * 64], tmp);\
op2(sum2, (w2)[1 * 64], tmp);\
tmp = p[2 * 64];\
op1(sum1, (w1)[2 * 64], tmp);\
op2(sum2, (w2)[2 * 64], tmp);\
tmp = p[3 * 64];\
op1(sum1, (w1)[3 * 64], tmp);\
op2(sum2, (w2)[3 * 64], tmp);\
tmp = p[4 * 64];\
op1(sum1, (w1)[4 * 64], tmp);\
op2(sum2, (w2)[4 * 64], tmp);\
tmp = p[5 * 64];\
op1(sum1, (w1)[5 * 64], tmp);\
op2(sum2, (w2)[5 * 64], tmp);\
tmp = p[6 * 64];\
op1(sum1, (w1)[6 * 64], tmp);\
op2(sum2, (w2)[6 * 64], tmp);\
tmp = p[7 * 64];\
op1(sum1, (w1)[7 * 64], tmp);\
op2(sum2, (w2)[7 * 64], tmp);\
}
void av_cold ff_mpa_synth_init(MPA_INT *window)
{
int i;
/* max = 18760, max sum over all 16 coefs : 44736 */
for(i=0;i<257;i++) {
int v;
v = ff_mpa_enwindow[i];
#if WFRAC_BITS < 16
v = (v + (1 << (16 - WFRAC_BITS - 1))) >> (16 - WFRAC_BITS);
#endif
window[i] = v;
if ((i & 63) != 0)
v = -v;
if (i != 0)
window[512 - i] = v;
}
}
/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:
32 samples. */
/* XXX: optimize by avoiding ring buffer usage */
void ff_mpa_synth_filter(MPA_INT *synth_buf_ptr, int *synth_buf_offset,
MPA_INT *window, int *dither_state,
OUT_INT *samples, int incr,
int32_t sb_samples[SBLIMIT])
{
int32_t tmp[32];
register MPA_INT *synth_buf;
register const MPA_INT *w, *w2, *p;
int j, offset, v;
OUT_INT *samples2;
#if FRAC_BITS <= 15
int sum, sum2;
#else
int64_t sum, sum2;
#endif
dct32(tmp, sb_samples);
offset = *synth_buf_offset;
synth_buf = synth_buf_ptr + offset;
for(j=0;j<32;j++) {
v = tmp[j];
#if FRAC_BITS <= 15
/* NOTE: can cause a loss in precision if very high amplitude
sound */
v = av_clip_int16(v);
#endif
synth_buf[j] = v;
}
/* copy to avoid wrap */
memcpy(synth_buf + 512, synth_buf, 32 * sizeof(MPA_INT));
samples2 = samples + 31 * incr;
w = window;
w2 = window + 31;
sum = *dither_state;
p = synth_buf + 16;
SUM8(MACS, sum, w, p);
p = synth_buf + 48;
SUM8(MLSS, sum, w + 32, p);
*samples = round_sample(&sum);
samples += incr;
w++;
/* we calculate two samples at the same time to avoid one memory
access per two sample */
for(j=1;j<16;j++) {
sum2 = 0;
p = synth_buf + 16 + j;
SUM8P2(sum, MACS, sum2, MLSS, w, w2, p);
p = synth_buf + 48 - j;
SUM8P2(sum, MLSS, sum2, MLSS, w + 32, w2 + 32, p);
*samples = round_sample(&sum);
samples += incr;
sum += sum2;
*samples2 = round_sample(&sum);
samples2 -= incr;
w++;
w2--;
}
p = synth_buf + 32;
SUM8(MLSS, sum, w + 32, p);
*samples = round_sample(&sum);
*dither_state= sum;
offset = (offset - 32) & 511;
*synth_buf_offset = offset;
}
#define C3 FIXHR(0.86602540378443864676/2)
/* 0.5 / cos(pi*(2*i+1)/36) */
static const int icos36[9] = {
FIXR(0.50190991877167369479),
FIXR(0.51763809020504152469), //0
FIXR(0.55168895948124587824),
FIXR(0.61038729438072803416),
FIXR(0.70710678118654752439), //1
FIXR(0.87172339781054900991),
FIXR(1.18310079157624925896),
FIXR(1.93185165257813657349), //2
FIXR(5.73685662283492756461),
};
/* 0.5 / cos(pi*(2*i+1)/36) */
static const int icos36h[9] = {
FIXHR(0.50190991877167369479/2),
FIXHR(0.51763809020504152469/2), //0
FIXHR(0.55168895948124587824/2),
FIXHR(0.61038729438072803416/2),
FIXHR(0.70710678118654752439/2), //1
FIXHR(0.87172339781054900991/2),
FIXHR(1.18310079157624925896/4),
FIXHR(1.93185165257813657349/4), //2
// FIXHR(5.73685662283492756461),
};
/* 12 points IMDCT. We compute it "by hand" by factorizing obvious
cases. */
static void imdct12(int *out, int *in)
{
int in0, in1, in2, in3, in4, in5, t1, t2;
in0= in[0*3];
in1= in[1*3] + in[0*3];
in2= in[2*3] + in[1*3];
in3= in[3*3] + in[2*3];
in4= in[4*3] + in[3*3];
in5= in[5*3] + in[4*3];
in5 += in3;
in3 += in1;
in2= MULH(2*in2, C3);
in3= MULH(4*in3, C3);
t1 = in0 - in4;
t2 = MULH(2*(in1 - in5), icos36h[4]);
out[ 7]=
out[10]= t1 + t2;
out[ 1]=
out[ 4]= t1 - t2;
in0 += in4>>1;
in4 = in0 + in2;
in5 += 2*in1;
in1 = MULH(in5 + in3, icos36h[1]);
out[ 8]=
out[ 9]= in4 + in1;
out[ 2]=
out[ 3]= in4 - in1;
in0 -= in2;
in5 = MULH(2*(in5 - in3), icos36h[7]);
out[ 0]=
out[ 5]= in0 - in5;
out[ 6]=
out[11]= in0 + in5;
}
/* cos(pi*i/18) */
#define C1 FIXHR(0.98480775301220805936/2)
#define C2 FIXHR(0.93969262078590838405/2)
#define C3 FIXHR(0.86602540378443864676/2)
#define C4 FIXHR(0.76604444311897803520/2)
#define C5 FIXHR(0.64278760968653932632/2)
#define C6 FIXHR(0.5/2)
#define C7 FIXHR(0.34202014332566873304/2)
#define C8 FIXHR(0.17364817766693034885/2)
/* using Lee like decomposition followed by hand coded 9 points DCT */
static void imdct36(int *out, int *buf, int *in, int *win)
{
int i, j, t0, t1, t2, t3, s0, s1, s2, s3;
int tmp[18], *tmp1, *in1;
for(i=17;i>=1;i--)
in[i] += in[i-1];
for(i=17;i>=3;i-=2)
in[i] += in[i-2];
for(j=0;j<2;j++) {
tmp1 = tmp + j;
in1 = in + j;
#if 0
//more accurate but slower
int64_t t0, t1, t2, t3;
t2 = in1[2*4] + in1[2*8] - in1[2*2];
t3 = (in1[2*0] + (int64_t)(in1[2*6]>>1))<<32;
t1 = in1[2*0] - in1[2*6];
tmp1[ 6] = t1 - (t2>>1);
tmp1[16] = t1 + t2;
t0 = MUL64(2*(in1[2*2] + in1[2*4]), C2);
t1 = MUL64( in1[2*4] - in1[2*8] , -2*C8);
t2 = MUL64(2*(in1[2*2] + in1[2*8]), -C4);
tmp1[10] = (t3 - t0 - t2) >> 32;
tmp1[ 2] = (t3 + t0 + t1) >> 32;
tmp1[14] = (t3 + t2 - t1) >> 32;
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7] - in1[2*1]), -C3);
t2 = MUL64(2*(in1[2*1] + in1[2*5]), C1);
t3 = MUL64( in1[2*5] - in1[2*7] , -2*C7);
t0 = MUL64(2*in1[2*3], C3);
t1 = MUL64(2*(in1[2*1] + in1[2*7]), -C5);
tmp1[ 0] = (t2 + t3 + t0) >> 32;
tmp1[12] = (t2 + t1 - t0) >> 32;
tmp1[ 8] = (t3 - t1 - t0) >> 32;
#else
t2 = in1[2*4] + in1[2*8] - in1[2*2];
t3 = in1[2*0] + (in1[2*6]>>1);
t1 = in1[2*0] - in1[2*6];
tmp1[ 6] = t1 - (t2>>1);
tmp1[16] = t1 + t2;
t0 = MULH(2*(in1[2*2] + in1[2*4]), C2);
t1 = MULH( in1[2*4] - in1[2*8] , -2*C8);
t2 = MULH(2*(in1[2*2] + in1[2*8]), -C4);
tmp1[10] = t3 - t0 - t2;
tmp1[ 2] = t3 + t0 + t1;
tmp1[14] = t3 + t2 - t1;
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7] - in1[2*1]), -C3);
t2 = MULH(2*(in1[2*1] + in1[2*5]), C1);
t3 = MULH( in1[2*5] - in1[2*7] , -2*C7);
t0 = MULH(2*in1[2*3], C3);
t1 = MULH(2*(in1[2*1] + in1[2*7]), -C5);
tmp1[ 0] = t2 + t3 + t0;
tmp1[12] = t2 + t1 - t0;
tmp1[ 8] = t3 - t1 - t0;
#endif
}
i = 0;
for(j=0;j<4;j++) {
t0 = tmp[i];
t1 = tmp[i + 2];
s0 = t1 + t0;
s2 = t1 - t0;
t2 = tmp[i + 1];
t3 = tmp[i + 3];
s1 = MULH(2*(t3 + t2), icos36h[j]);
s3 = MULL(t3 - t2, icos36[8 - j], FRAC_BITS);
t0 = s0 + s1;
t1 = s0 - s1;
out[(9 + j)*SBLIMIT] = MULH(t1, win[9 + j]) + buf[9 + j];
out[(8 - j)*SBLIMIT] = MULH(t1, win[8 - j]) + buf[8 - j];
buf[9 + j] = MULH(t0, win[18 + 9 + j]);
buf[8 - j] = MULH(t0, win[18 + 8 - j]);
t0 = s2 + s3;
t1 = s2 - s3;
out[(9 + 8 - j)*SBLIMIT] = MULH(t1, win[9 + 8 - j]) + buf[9 + 8 - j];
out[( j)*SBLIMIT] = MULH(t1, win[ j]) + buf[ j];
buf[9 + 8 - j] = MULH(t0, win[18 + 9 + 8 - j]);
buf[ + j] = MULH(t0, win[18 + j]);
i += 4;
}
s0 = tmp[16];
s1 = MULH(2*tmp[17], icos36h[4]);
t0 = s0 + s1;
t1 = s0 - s1;
out[(9 + 4)*SBLIMIT] = MULH(t1, win[9 + 4]) + buf[9 + 4];
out[(8 - 4)*SBLIMIT] = MULH(t1, win[8 - 4]) + buf[8 - 4];
buf[9 + 4] = MULH(t0, win[18 + 9 + 4]);
buf[8 - 4] = MULH(t0, win[18 + 8 - 4]);
}
/* return the number of decoded frames */
static int mp_decode_layer1(MPADecodeContext *s)
{
int bound, i, v, n, ch, j, mant;
uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT];
uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT];
if (s->mode == MPA_JSTEREO)
bound = (s->mode_ext + 1) * 4;
else
bound = SBLIMIT;
/* allocation bits */
for(i=0;i<bound;i++) {
for(ch=0;ch<s->nb_channels;ch++) {
allocation[ch][i] = get_bits(&s->gb, 4);
}
}
for(i=bound;i<SBLIMIT;i++) {
allocation[0][i] = get_bits(&s->gb, 4);
}
/* scale factors */
for(i=0;i<bound;i++) {
for(ch=0;ch<s->nb_channels;ch++) {
if (allocation[ch][i])
scale_factors[ch][i] = get_bits(&s->gb, 6);
}
}
for(i=bound;i<SBLIMIT;i++) {
if (allocation[0][i]) {
scale_factors[0][i] = get_bits(&s->gb, 6);
scale_factors[1][i] = get_bits(&s->gb, 6);
}
}
/* compute samples */
for(j=0;j<12;j++) {
for(i=0;i<bound;i++) {
for(ch=0;ch<s->nb_channels;ch++) {
n = allocation[ch][i];
if (n) {
mant = get_bits(&s->gb, n + 1);
v = l1_unscale(n, mant, scale_factors[ch][i]);
} else {
v = 0;
}
s->sb_samples[ch][j][i] = v;
}
}
for(i=bound;i<SBLIMIT;i++) {
n = allocation[0][i];
if (n) {
mant = get_bits(&s->gb, n + 1);
v = l1_unscale(n, mant, scale_factors[0][i]);
s->sb_samples[0][j][i] = v;
v = l1_unscale(n, mant, scale_factors[1][i]);
s->sb_samples[1][j][i] = v;
} else {
s->sb_samples[0][j][i] = 0;
s->sb_samples[1][j][i] = 0;
}
}
}
return 12;
}
static int mp_decode_layer2(MPADecodeContext *s)
{
int sblimit; /* number of used subbands */
const unsigned char *alloc_table;
int table, bit_alloc_bits, i, j, ch, bound, v;
unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT];
unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];
unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf;
int scale, qindex, bits, steps, k, l, m, b;
/* select decoding table */
table = ff_mpa_l2_select_table(s->bit_rate / 1000, s->nb_channels,
s->sample_rate, s->lsf);
sblimit = ff_mpa_sblimit_table[table];
alloc_table = ff_mpa_alloc_tables[table];
if (s->mode == MPA_JSTEREO)
bound = (s->mode_ext + 1) * 4;
else
bound = sblimit;
dprintf(s->avctx, "bound=%d sblimit=%d\n", bound, sblimit);
/* sanity check */
if( bound > sblimit ) bound = sblimit;
/* parse bit allocation */
j = 0;
for(i=0;i<bound;i++) {
bit_alloc_bits = alloc_table[j];
for(ch=0;ch<s->nb_channels;ch++) {
bit_alloc[ch][i] = get_bits(&s->gb, bit_alloc_bits);
}
j += 1 << bit_alloc_bits;
}
for(i=bound;i<sblimit;i++) {
bit_alloc_bits = alloc_table[j];
v = get_bits(&s->gb, bit_alloc_bits);
bit_alloc[0][i] = v;
bit_alloc[1][i] = v;
j += 1 << bit_alloc_bits;
}
/* scale codes */
for(i=0;i<sblimit;i++) {
for(ch=0;ch<s->nb_channels;ch++) {
if (bit_alloc[ch][i])
scale_code[ch][i] = get_bits(&s->gb, 2);
}
}
/* scale factors */
for(i=0;i<sblimit;i++) {
for(ch=0;ch<s->nb_channels;ch++) {
if (bit_alloc[ch][i]) {
sf = scale_factors[ch][i];
switch(scale_code[ch][i]) {
default:
case 0:
sf[0] = get_bits(&s->gb, 6);
sf[1] = get_bits(&s->gb, 6);
sf[2] = get_bits(&s->gb, 6);
break;
case 2:
sf[0] = get_bits(&s->gb, 6);
sf[1] = sf[0];
sf[2] = sf[0];
break;
case 1:
sf[0] = get_bits(&s->gb, 6);
sf[2] = get_bits(&s->gb, 6);
sf[1] = sf[0];
break;
case 3:
sf[0] = get_bits(&s->gb, 6);
sf[2] = get_bits(&s->gb, 6);
sf[1] = sf[2];
break;
}
}
}
}
/* samples */
for(k=0;k<3;k++) {
for(l=0;l<12;l+=3) {
j = 0;
for(i=0;i<bound;i++) {
bit_alloc_bits = alloc_table[j];
for(ch=0;ch<s->nb_channels;ch++) {
b = bit_alloc[ch][i];
if (b) {
scale = scale_factors[ch][i][k];
qindex = alloc_table[j+b];
bits = ff_mpa_quant_bits[qindex];
if (bits < 0) {
/* 3 values at the same time */
v = get_bits(&s->gb, -bits);
steps = ff_mpa_quant_steps[qindex];
s->sb_samples[ch][k * 12 + l + 0][i] =
l2_unscale_group(steps, v % steps, scale);
v = v / steps;
s->sb_samples[ch][k * 12 + l + 1][i] =
l2_unscale_group(steps, v % steps, scale);
v = v / steps;
s->sb_samples[ch][k * 12 + l + 2][i] =
l2_unscale_group(steps, v, scale);
} else {
for(m=0;m<3;m++) {
v = get_bits(&s->gb, bits);
v = l1_unscale(bits - 1, v, scale);
s->sb_samples[ch][k * 12 + l + m][i] = v;
}
}
} else {
s->sb_samples[ch][k * 12 + l + 0][i] = 0;
s->sb_samples[ch][k * 12 + l + 1][i] = 0;
s->sb_samples[ch][k * 12 + l + 2][i] = 0;
}
}
/* next subband in alloc table */
j += 1 << bit_alloc_bits;
}
/* XXX: find a way to avoid this duplication of code */
for(i=bound;i<sblimit;i++) {
bit_alloc_bits = alloc_table[j];
b = bit_alloc[0][i];
if (b) {
int mant, scale0, scale1;
scale0 = scale_factors[0][i][k];
scale1 = scale_factors[1][i][k];
qindex = alloc_table[j+b];
bits = ff_mpa_quant_bits[qindex];
if (bits < 0) {
/* 3 values at the same time */
v = get_bits(&s->gb, -bits);
steps = ff_mpa_quant_steps[qindex];
mant = v % steps;
v = v / steps;
s->sb_samples[0][k * 12 + l + 0][i] =
l2_unscale_group(steps, mant, scale0);
s->sb_samples[1][k * 12 + l + 0][i] =
l2_unscale_group(steps, mant, scale1);
mant = v % steps;
v = v / steps;
s->sb_samples[0][k * 12 + l + 1][i] =
l2_unscale_group(steps, mant, scale0);
s->sb_samples[1][k * 12 + l + 1][i] =
l2_unscale_group(steps, mant, scale1);
s->sb_samples[0][k * 12 + l + 2][i] =
l2_unscale_group(steps, v, scale0);
s->sb_samples[1][k * 12 + l + 2][i] =
l2_unscale_group(steps, v, scale1);
} else {
for(m=0;m<3;m++) {
mant = get_bits(&s->gb, bits);
s->sb_samples[0][k * 12 + l + m][i] =
l1_unscale(bits - 1, mant, scale0);
s->sb_samples[1][k * 12 + l + m][i] =
l1_unscale(bits - 1, mant, scale1);
}
}
} else {
s->sb_samples[0][k * 12 + l + 0][i] = 0;
s->sb_samples[0][k * 12 + l + 1][i] = 0;
s->sb_samples[0][k * 12 + l + 2][i] = 0;
s->sb_samples[1][k * 12 + l + 0][i] = 0;
s->sb_samples[1][k * 12 + l + 1][i] = 0;
s->sb_samples[1][k * 12 + l + 2][i] = 0;
}
/* next subband in alloc table */
j += 1 << bit_alloc_bits;
}
/* fill remaining samples to zero */
for(i=sblimit;i<SBLIMIT;i++) {
for(ch=0;ch<s->nb_channels;ch++) {
s->sb_samples[ch][k * 12 + l + 0][i] = 0;
s->sb_samples[ch][k * 12 + l + 1][i] = 0;
s->sb_samples[ch][k * 12 + l + 2][i] = 0;
}
}
}
}
return 3 * 12;
}
static inline void lsf_sf_expand(int *slen,
int sf, int n1, int n2, int n3)
{
if (n3) {
slen[3] = sf % n3;
sf /= n3;
} else {
slen[3] = 0;
}
if (n2) {
slen[2] = sf % n2;
sf /= n2;
} else {
slen[2] = 0;
}
slen[1] = sf % n1;
sf /= n1;
slen[0] = sf;
}
static void exponents_from_scale_factors(MPADecodeContext *s,
GranuleDef *g,
int16_t *exponents)
{
const uint8_t *bstab, *pretab;
int len, i, j, k, l, v0, shift, gain, gains[3];
int16_t *exp_ptr;
exp_ptr = exponents;
gain = g->global_gain - 210;
shift = g->scalefac_scale + 1;
bstab = band_size_long[s->sample_rate_index];
pretab = mpa_pretab[g->preflag];
for(i=0;i<g->long_end;i++) {
v0 = gain - ((g->scale_factors[i] + pretab[i]) << shift) + 400;
len = bstab[i];
for(j=len;j>0;j--)
*exp_ptr++ = v0;
}
if (g->short_start < 13) {
bstab = band_size_short[s->sample_rate_index];
gains[0] = gain - (g->subblock_gain[0] << 3);
gains[1] = gain - (g->subblock_gain[1] << 3);
gains[2] = gain - (g->subblock_gain[2] << 3);
k = g->long_end;
for(i=g->short_start;i<13;i++) {
len = bstab[i];
for(l=0;l<3;l++) {
v0 = gains[l] - (g->scale_factors[k++] << shift) + 400;
for(j=len;j>0;j--)
*exp_ptr++ = v0;
}
}
}
}
/* handle n = 0 too */
static inline int get_bitsz(GetBitContext *s, int n)
{
if (n == 0)
return 0;
else
return get_bits(s, n);
}
static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos, int *end_pos2){
if(s->in_gb.buffer && *pos >= s->gb.size_in_bits){
s->gb= s->in_gb;
s->in_gb.buffer=NULL;
assert((get_bits_count(&s->gb) & 7) == 0);
skip_bits_long(&s->gb, *pos - *end_pos);
*end_pos2=
*end_pos= *end_pos2 + get_bits_count(&s->gb) - *pos;
*pos= get_bits_count(&s->gb);
}
}
static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
int16_t *exponents, int end_pos2)
{
int s_index;
int i;
int last_pos, bits_left;
VLC *vlc;
int end_pos= FFMIN(end_pos2, s->gb.size_in_bits);
/* low frequencies (called big values) */
s_index = 0;
for(i=0;i<3;i++) {
int j, k, l, linbits;
j = g->region_size[i];
if (j == 0)
continue;
/* select vlc table */
k = g->table_select[i];
l = mpa_huff_data[k][0];
linbits = mpa_huff_data[k][1];
vlc = &huff_vlc[l];
if(!l){
memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid)*2*j);
s_index += 2*j;
continue;
}
/* read huffcode and compute each couple */
for(;j>0;j--) {
int exponent, x, y, v;
int pos= get_bits_count(&s->gb);
if (pos >= end_pos){
// av_log(NULL, AV_LOG_ERROR, "pos: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
switch_buffer(s, &pos, &end_pos, &end_pos2);
// av_log(NULL, AV_LOG_ERROR, "new pos: %d %d\n", pos, end_pos);
if(pos >= end_pos)
break;
}
y = get_vlc2(&s->gb, vlc->table, 7, 3);
if(!y){
g->sb_hybrid[s_index ] =
g->sb_hybrid[s_index+1] = 0;
s_index += 2;
continue;
}
exponent= exponents[s_index];
dprintf(s->avctx, "region=%d n=%d x=%d y=%d exp=%d\n",
i, g->region_size[i] - j, x, y, exponent);
if(y&16){
x = y >> 5;
y = y & 0x0f;
if (x < 15){
v = expval_table[ exponent ][ x ];
// v = expval_table[ (exponent&3) ][ x ] >> FFMIN(0 - (exponent>>2), 31);
}else{
x += get_bitsz(&s->gb, linbits);
v = l3_unscale(x, exponent);
}
if (get_bits1(&s->gb))
v = -v;
g->sb_hybrid[s_index] = v;
if (y < 15){
v = expval_table[ exponent ][ y ];
}else{
y += get_bitsz(&s->gb, linbits);
v = l3_unscale(y, exponent);
}
if (get_bits1(&s->gb))
v = -v;
g->sb_hybrid[s_index+1] = v;
}else{
x = y >> 5;
y = y & 0x0f;
x += y;
if (x < 15){
v = expval_table[ exponent ][ x ];
}else{
x += get_bitsz(&s->gb, linbits);
v = l3_unscale(x, exponent);
}
if (get_bits1(&s->gb))
v = -v;
g->sb_hybrid[s_index+!!y] = v;
g->sb_hybrid[s_index+ !y] = 0;
}
s_index+=2;
}
}
/* high frequencies */
vlc = &huff_quad_vlc[g->count1table_select];
last_pos=0;
while (s_index <= 572) {
int pos, code;
pos = get_bits_count(&s->gb);
if (pos >= end_pos) {
if (pos > end_pos2 && last_pos){
/* some encoders generate an incorrect size for this
part. We must go back into the data */
s_index -= 4;
skip_bits_long(&s->gb, last_pos - pos);
av_log(s->avctx, AV_LOG_INFO, "overread, skip %d enddists: %d %d\n", last_pos - pos, end_pos-pos, end_pos2-pos);
if(s->error_recognition >= FF_ER_COMPLIANT)
s_index=0;
break;
}
// av_log(NULL, AV_LOG_ERROR, "pos2: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
switch_buffer(s, &pos, &end_pos, &end_pos2);
// av_log(NULL, AV_LOG_ERROR, "new pos2: %d %d %d\n", pos, end_pos, s_index);
if(pos >= end_pos)
break;
}
last_pos= pos;
code = get_vlc2(&s->gb, vlc->table, vlc->bits, 1);
dprintf(s->avctx, "t=%d code=%d\n", g->count1table_select, code);
g->sb_hybrid[s_index+0]=
g->sb_hybrid[s_index+1]=
g->sb_hybrid[s_index+2]=
g->sb_hybrid[s_index+3]= 0;
while(code){
static const int idxtab[16]={3,3,2,2,1,1,1,1,0,0,0,0,0,0,0,0};
int v;
int pos= s_index+idxtab[code];
code ^= 8>>idxtab[code];
v = exp_table[ exponents[pos] ];
// v = exp_table[ (exponents[pos]&3) ] >> FFMIN(0 - (exponents[pos]>>2), 31);
if(get_bits1(&s->gb))
v = -v;
g->sb_hybrid[pos] = v;
}
s_index+=4;
}
/* skip extension bits */
bits_left = end_pos2 - get_bits_count(&s->gb);
//av_log(NULL, AV_LOG_ERROR, "left:%d buf:%p\n", bits_left, s->in_gb.buffer);
if (bits_left < 0 && s->error_recognition >= FF_ER_COMPLIANT) {
av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);
s_index=0;
}else if(bits_left > 0 && s->error_recognition >= FF_ER_AGGRESSIVE){
av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);
s_index=0;
}
memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid)*(576 - s_index));
skip_bits_long(&s->gb, bits_left);
i= get_bits_count(&s->gb);
switch_buffer(s, &i, &end_pos, &end_pos2);
return 0;
}
/* Reorder short blocks from bitstream order to interleaved order. It
would be faster to do it in parsing, but the code would be far more
complicated */
static void reorder_block(MPADecodeContext *s, GranuleDef *g)
{
int i, j, len;
int32_t *ptr, *dst, *ptr1;
int32_t tmp[576];
if (g->block_type != 2)
return;
if (g->switch_point) {
if (s->sample_rate_index != 8) {
ptr = g->sb_hybrid + 36;
} else {
ptr = g->sb_hybrid + 48;
}
} else {
ptr = g->sb_hybrid;
}
for(i=g->short_start;i<13;i++) {
len = band_size_short[s->sample_rate_index][i];
ptr1 = ptr;
dst = tmp;
for(j=len;j>0;j--) {
*dst++ = ptr[0*len];
*dst++ = ptr[1*len];
*dst++ = ptr[2*len];
ptr++;
}
ptr+=2*len;
memcpy(ptr1, tmp, len * 3 * sizeof(*ptr1));
}
}
#define ISQRT2 FIXR(0.70710678118654752440)
static void compute_stereo(MPADecodeContext *s,
GranuleDef *g0, GranuleDef *g1)
{
int i, j, k, l;
int32_t v1, v2;
int sf_max, tmp0, tmp1, sf, len, non_zero_found;
int32_t (*is_tab)[16];
int32_t *tab0, *tab1;
int non_zero_found_short[3];
/* intensity stereo */
if (s->mode_ext & MODE_EXT_I_STEREO) {
if (!s->lsf) {
is_tab = is_table;
sf_max = 7;
} else {
is_tab = is_table_lsf[g1->scalefac_compress & 1];
sf_max = 16;
}
tab0 = g0->sb_hybrid + 576;
tab1 = g1->sb_hybrid + 576;
non_zero_found_short[0] = 0;
non_zero_found_short[1] = 0;
non_zero_found_short[2] = 0;
k = (13 - g1->short_start) * 3 + g1->long_end - 3;
for(i = 12;i >= g1->short_start;i--) {
/* for last band, use previous scale factor */
if (i != 11)
k -= 3;
len = band_size_short[s->sample_rate_index][i];
for(l=2;l>=0;l--) {
tab0 -= len;
tab1 -= len;
if (!non_zero_found_short[l]) {
/* test if non zero band. if so, stop doing i-stereo */
for(j=0;j<len;j++) {
if (tab1[j] != 0) {
non_zero_found_short[l] = 1;
goto found1;
}
}
sf = g1->scale_factors[k + l];
if (sf >= sf_max)
goto found1;
v1 = is_tab[0][sf];
v2 = is_tab[1][sf];
for(j=0;j<len;j++) {
tmp0 = tab0[j];
tab0[j] = MULL(tmp0, v1, FRAC_BITS);
tab1[j] = MULL(tmp0, v2, FRAC_BITS);
}
} else {
found1:
if (s->mode_ext & MODE_EXT_MS_STEREO) {
/* lower part of the spectrum : do ms stereo
if enabled */
for(j=0;j<len;j++) {
tmp0 = tab0[j];
tmp1 = tab1[j];
tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS);
tab1[j] = MULL(tmp0 - tmp1, ISQRT2, FRAC_BITS);
}
}
}
}
}
non_zero_found = non_zero_found_short[0] |
non_zero_found_short[1] |
non_zero_found_short[2];
for(i = g1->long_end - 1;i >= 0;i--) {
len = band_size_long[s->sample_rate_index][i];
tab0 -= len;
tab1 -= len;
/* test if non zero band. if so, stop doing i-stereo */
if (!non_zero_found) {
for(j=0;j<len;j++) {
if (tab1[j] != 0) {
non_zero_found = 1;
goto found2;
}
}
/* for last band, use previous scale factor */
k = (i == 21) ? 20 : i;
sf = g1->scale_factors[k];
if (sf >= sf_max)
goto found2;
v1 = is_tab[0][sf];
v2 = is_tab[1][sf];
for(j=0;j<len;j++) {
tmp0 = tab0[j];
tab0[j] = MULL(tmp0, v1, FRAC_BITS);
tab1[j] = MULL(tmp0, v2, FRAC_BITS);
}
} else {
found2:
if (s->mode_ext & MODE_EXT_MS_STEREO) {
/* lower part of the spectrum : do ms stereo
if enabled */
for(j=0;j<len;j++) {
tmp0 = tab0[j];
tmp1 = tab1[j];
tab0[j] = MULL(tmp0 + tmp1, ISQRT2, FRAC_BITS);
tab1[j] = MULL(tmp0 - tmp1, ISQRT2, FRAC_BITS);
}
}
}
}
} else if (s->mode_ext & MODE_EXT_MS_STEREO) {
/* ms stereo ONLY */
/* NOTE: the 1/sqrt(2) normalization factor is included in the
global gain */
tab0 = g0->sb_hybrid;
tab1 = g1->sb_hybrid;
for(i=0;i<576;i++) {
tmp0 = tab0[i];
tmp1 = tab1[i];
tab0[i] = tmp0 + tmp1;
tab1[i] = tmp0 - tmp1;
}
}
}
static void compute_antialias_integer(MPADecodeContext *s,
GranuleDef *g)
{
int32_t *ptr, *csa;
int n, i;
/* we antialias only "long" bands */
if (g->block_type == 2) {
if (!g->switch_point)
return;
/* XXX: check this for 8000Hz case */
n = 1;
} else {
n = SBLIMIT - 1;
}
ptr = g->sb_hybrid + 18;
for(i = n;i > 0;i--) {
int tmp0, tmp1, tmp2;
csa = &csa_table[0][0];
#define INT_AA(j) \
tmp0 = ptr[-1-j];\
tmp1 = ptr[ j];\
tmp2= MULH(tmp0 + tmp1, csa[0+4*j]);\
ptr[-1-j] = 4*(tmp2 - MULH(tmp1, csa[2+4*j]));\
ptr[ j] = 4*(tmp2 + MULH(tmp0, csa[3+4*j]));
INT_AA(0)
INT_AA(1)
INT_AA(2)
INT_AA(3)
INT_AA(4)
INT_AA(5)
INT_AA(6)
INT_AA(7)
ptr += 18;
}
}
static void compute_antialias_float(MPADecodeContext *s,
GranuleDef *g)
{
int32_t *ptr;
int n, i;
/* we antialias only "long" bands */
if (g->block_type == 2) {
if (!g->switch_point)
return;
/* XXX: check this for 8000Hz case */
n = 1;
} else {
n = SBLIMIT - 1;
}
ptr = g->sb_hybrid + 18;
for(i = n;i > 0;i--) {
float tmp0, tmp1;
float *csa = &csa_table_float[0][0];
#define FLOAT_AA(j)\
tmp0= ptr[-1-j];\
tmp1= ptr[ j];\
ptr[-1-j] = lrintf(tmp0 * csa[0+4*j] - tmp1 * csa[1+4*j]);\
ptr[ j] = lrintf(tmp0 * csa[1+4*j] + tmp1 * csa[0+4*j]);
FLOAT_AA(0)
FLOAT_AA(1)
FLOAT_AA(2)
FLOAT_AA(3)
FLOAT_AA(4)
FLOAT_AA(5)
FLOAT_AA(6)
FLOAT_AA(7)
ptr += 18;
}
}
static void compute_imdct(MPADecodeContext *s,
GranuleDef *g,
int32_t *sb_samples,
int32_t *mdct_buf)
{
int32_t *ptr, *win, *win1, *buf, *out_ptr, *ptr1;
int32_t out2[12];
int i, j, mdct_long_end, v, sblimit;
/* find last non zero block */
ptr = g->sb_hybrid + 576;
ptr1 = g->sb_hybrid + 2 * 18;
while (ptr >= ptr1) {
ptr -= 6;
v = ptr[0] | ptr[1] | ptr[2] | ptr[3] | ptr[4] | ptr[5];
if (v != 0)
break;
}
sblimit = ((ptr - g->sb_hybrid) / 18) + 1;
if (g->block_type == 2) {
/* XXX: check for 8000 Hz */
if (g->switch_point)
mdct_long_end = 2;
else
mdct_long_end = 0;
} else {
mdct_long_end = sblimit;
}
buf = mdct_buf;
ptr = g->sb_hybrid;
for(j=0;j<mdct_long_end;j++) {
/* apply window & overlap with previous buffer */
out_ptr = sb_samples + j;
/* select window */
if (g->switch_point && j < 2)
win1 = mdct_win[0];
else
win1 = mdct_win[g->block_type];
/* select frequency inversion */
win = win1 + ((4 * 36) & -(j & 1));
imdct36(out_ptr, buf, ptr, win);
out_ptr += 18*SBLIMIT;
ptr += 18;
buf += 18;
}
for(j=mdct_long_end;j<sblimit;j++) {
/* select frequency inversion */
win = mdct_win[2] + ((4 * 36) & -(j & 1));
out_ptr = sb_samples + j;
for(i=0; i<6; i++){
*out_ptr = buf[i];
out_ptr += SBLIMIT;
}
imdct12(out2, ptr + 0);
for(i=0;i<6;i++) {
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*1];
buf[i + 6*2] = MULH(out2[i + 6], win[i + 6]);
out_ptr += SBLIMIT;
}
imdct12(out2, ptr + 1);
for(i=0;i<6;i++) {
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*2];
buf[i + 6*0] = MULH(out2[i + 6], win[i + 6]);
out_ptr += SBLIMIT;
}
imdct12(out2, ptr + 2);
for(i=0;i<6;i++) {
buf[i + 6*0] = MULH(out2[i], win[i]) + buf[i + 6*0];
buf[i + 6*1] = MULH(out2[i + 6], win[i + 6]);
buf[i + 6*2] = 0;
}
ptr += 18;
buf += 18;
}
/* zero bands */
for(j=sblimit;j<SBLIMIT;j++) {
/* overlap */
out_ptr = sb_samples + j;
for(i=0;i<18;i++) {
*out_ptr = buf[i];
buf[i] = 0;
out_ptr += SBLIMIT;
}
buf += 18;
}
}
/* main layer3 decoding function */
static int mp_decode_layer3(MPADecodeContext *s)
{
int nb_granules, main_data_begin, private_bits;
int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;
GranuleDef granules[2][2], *g;
int16_t exponents[576];
/* read side info */
if (s->lsf) {
main_data_begin = get_bits(&s->gb, 8);
private_bits = get_bits(&s->gb, s->nb_channels);
nb_granules = 1;
} else {
main_data_begin = get_bits(&s->gb, 9);
if (s->nb_channels == 2)
private_bits = get_bits(&s->gb, 3);
else
private_bits = get_bits(&s->gb, 5);
nb_granules = 2;
for(ch=0;ch<s->nb_channels;ch++) {
granules[ch][0].scfsi = 0; /* all scale factors are transmitted */
granules[ch][1].scfsi = get_bits(&s->gb, 4);
}
}
for(gr=0;gr<nb_granules;gr++) {
for(ch=0;ch<s->nb_channels;ch++) {
dprintf(s->avctx, "gr=%d ch=%d: side_info\n", gr, ch);
g = &granules[ch][gr];
g->part2_3_length = get_bits(&s->gb, 12);
g->big_values = get_bits(&s->gb, 9);
if(g->big_values > 288){
av_log(s->avctx, AV_LOG_ERROR, "big_values too big\n");
return -1;
}
g->global_gain = get_bits(&s->gb, 8);
/* if MS stereo only is selected, we precompute the
1/sqrt(2) renormalization factor */
if ((s->mode_ext & (MODE_EXT_MS_STEREO | MODE_EXT_I_STEREO)) ==
MODE_EXT_MS_STEREO)
g->global_gain -= 2;
if (s->lsf)
g->scalefac_compress = get_bits(&s->gb, 9);
else
g->scalefac_compress = get_bits(&s->gb, 4);
blocksplit_flag = get_bits1(&s->gb);
if (blocksplit_flag) {
g->block_type = get_bits(&s->gb, 2);
if (g->block_type == 0){
av_log(s->avctx, AV_LOG_ERROR, "invalid block type\n");
return -1;
}
g->switch_point = get_bits1(&s->gb);
for(i=0;i<2;i++)
g->table_select[i] = get_bits(&s->gb, 5);
for(i=0;i<3;i++)
g->subblock_gain[i] = get_bits(&s->gb, 3);
ff_init_short_region(s, g);
} else {
int region_address1, region_address2;
g->block_type = 0;
g->switch_point = 0;
for(i=0;i<3;i++)
g->table_select[i] = get_bits(&s->gb, 5);
/* compute huffman coded region sizes */
region_address1 = get_bits(&s->gb, 4);
region_address2 = get_bits(&s->gb, 3);
dprintf(s->avctx, "region1=%d region2=%d\n",
region_address1, region_address2);
ff_init_long_region(s, g, region_address1, region_address2);
}
ff_region_offset2size(g);
ff_compute_band_indexes(s, g);
g->preflag = 0;
if (!s->lsf)
g->preflag = get_bits1(&s->gb);
g->scalefac_scale = get_bits1(&s->gb);
g->count1table_select = get_bits1(&s->gb);
dprintf(s->avctx, "block_type=%d switch_point=%d\n",
g->block_type, g->switch_point);
}
}
if (!s->adu_mode) {
const uint8_t *ptr = s->gb.buffer + (get_bits_count(&s->gb)>>3);
assert((get_bits_count(&s->gb) & 7) == 0);
/* now we get bits from the main_data_begin offset */
dprintf(s->avctx, "seekback: %d\n", main_data_begin);
//av_log(NULL, AV_LOG_ERROR, "backstep:%d, lastbuf:%d\n", main_data_begin, s->last_buf_size);
memcpy(s->last_buf + s->last_buf_size, ptr, EXTRABYTES);
s->in_gb= s->gb;
init_get_bits(&s->gb, s->last_buf, s->last_buf_size*8);
skip_bits_long(&s->gb, 8*(s->last_buf_size - main_data_begin));
}
for(gr=0;gr<nb_granules;gr++) {
for(ch=0;ch<s->nb_channels;ch++) {
g = &granules[ch][gr];
if(get_bits_count(&s->gb)<0){
av_log(s->avctx, AV_LOG_ERROR, "mdb:%d, lastbuf:%d skipping granule %d\n",
main_data_begin, s->last_buf_size, gr);
skip_bits_long(&s->gb, g->part2_3_length);
memset(g->sb_hybrid, 0, sizeof(g->sb_hybrid));
if(get_bits_count(&s->gb) >= s->gb.size_in_bits && s->in_gb.buffer){
skip_bits_long(&s->in_gb, get_bits_count(&s->gb) - s->gb.size_in_bits);
s->gb= s->in_gb;
s->in_gb.buffer=NULL;
}
continue;
}
bits_pos = get_bits_count(&s->gb);
if (!s->lsf) {
uint8_t *sc;
int slen, slen1, slen2;
/* MPEG1 scale factors */
slen1 = slen_table[0][g->scalefac_compress];
slen2 = slen_table[1][g->scalefac_compress];
dprintf(s->avctx, "slen1=%d slen2=%d\n", slen1, slen2);
if (g->block_type == 2) {
n = g->switch_point ? 17 : 18;
j = 0;
if(slen1){
for(i=0;i<n;i++)
g->scale_factors[j++] = get_bits(&s->gb, slen1);
}else{
for(i=0;i<n;i++)
g->scale_factors[j++] = 0;
}
if(slen2){
for(i=0;i<18;i++)
g->scale_factors[j++] = get_bits(&s->gb, slen2);
for(i=0;i<3;i++)
g->scale_factors[j++] = 0;
}else{
for(i=0;i<21;i++)
g->scale_factors[j++] = 0;
}
} else {
sc = granules[ch][0].scale_factors;
j = 0;
for(k=0;k<4;k++) {
n = (k == 0 ? 6 : 5);
if ((g->scfsi & (0x8 >> k)) == 0) {
slen = (k < 2) ? slen1 : slen2;
if(slen){
for(i=0;i<n;i++)
g->scale_factors[j++] = get_bits(&s->gb, slen);
}else{
for(i=0;i<n;i++)
g->scale_factors[j++] = 0;
}
} else {
/* simply copy from last granule */
for(i=0;i<n;i++) {
g->scale_factors[j] = sc[j];
j++;
}
}
}
g->scale_factors[j++] = 0;
}
} else {
int tindex, tindex2, slen[4], sl, sf;
/* LSF scale factors */
if (g->block_type == 2) {
tindex = g->switch_point ? 2 : 1;
} else {
tindex = 0;
}
sf = g->scalefac_compress;
if ((s->mode_ext & MODE_EXT_I_STEREO) && ch == 1) {
/* intensity stereo case */
sf >>= 1;
if (sf < 180) {
lsf_sf_expand(slen, sf, 6, 6, 0);
tindex2 = 3;
} else if (sf < 244) {
lsf_sf_expand(slen, sf - 180, 4, 4, 0);
tindex2 = 4;
} else {
lsf_sf_expand(slen, sf - 244, 3, 0, 0);
tindex2 = 5;
}
} else {
/* normal case */
if (sf < 400) {
lsf_sf_expand(slen, sf, 5, 4, 4);
tindex2 = 0;
} else if (sf < 500) {
lsf_sf_expand(slen, sf - 400, 5, 4, 0);
tindex2 = 1;
} else {
lsf_sf_expand(slen, sf - 500, 3, 0, 0);
tindex2 = 2;
g->preflag = 1;
}
}
j = 0;
for(k=0;k<4;k++) {
n = lsf_nsf_table[tindex2][tindex][k];
sl = slen[k];
if(sl){
for(i=0;i<n;i++)
g->scale_factors[j++] = get_bits(&s->gb, sl);
}else{
for(i=0;i<n;i++)
g->scale_factors[j++] = 0;
}
}
/* XXX: should compute exact size */
for(;j<40;j++)
g->scale_factors[j] = 0;
}
exponents_from_scale_factors(s, g, exponents);
/* read Huffman coded residue */
huffman_decode(s, g, exponents, bits_pos + g->part2_3_length);
} /* ch */
if (s->nb_channels == 2)
compute_stereo(s, &granules[0][gr], &granules[1][gr]);
for(ch=0;ch<s->nb_channels;ch++) {
g = &granules[ch][gr];
reorder_block(s, g);
s->compute_antialias(s, g);
compute_imdct(s, g, &s->sb_samples[ch][18 * gr][0], s->mdct_buf[ch]);
}
} /* gr */
if(get_bits_count(&s->gb)<0)
skip_bits_long(&s->gb, -get_bits_count(&s->gb));
return nb_granules * 18;
}
static int mp_decode_frame(MPADecodeContext *s,
OUT_INT *samples, const uint8_t *buf, int buf_size)
{
int i, nb_frames, ch;
OUT_INT *samples_ptr;
init_get_bits(&s->gb, buf + HEADER_SIZE, (buf_size - HEADER_SIZE)*8);
/* skip error protection field */
if (s->error_protection)
skip_bits(&s->gb, 16);
dprintf(s->avctx, "frame %d:\n", s->frame_count);
switch(s->layer) {
case 1:
s->avctx->frame_size = 384;
nb_frames = mp_decode_layer1(s);
break;
case 2:
s->avctx->frame_size = 1152;
nb_frames = mp_decode_layer2(s);
break;
case 3:
s->avctx->frame_size = s->lsf ? 576 : 1152;
default:
nb_frames = mp_decode_layer3(s);
s->last_buf_size=0;
if(s->in_gb.buffer){
align_get_bits(&s->gb);
i= (s->gb.size_in_bits - get_bits_count(&s->gb))>>3;
if(i >= 0 && i <= BACKSTEP_SIZE){
memmove(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), i);
s->last_buf_size=i;
}else
av_log(s->avctx, AV_LOG_ERROR, "invalid old backstep %d\n", i);
s->gb= s->in_gb;
s->in_gb.buffer= NULL;
}
align_get_bits(&s->gb);
assert((get_bits_count(&s->gb) & 7) == 0);
i= (s->gb.size_in_bits - get_bits_count(&s->gb))>>3;
if(i<0 || i > BACKSTEP_SIZE || nb_frames<0){
if(i<0)
av_log(s->avctx, AV_LOG_ERROR, "invalid new backstep %d\n", i);
i= FFMIN(BACKSTEP_SIZE, buf_size - HEADER_SIZE);
}
assert(i <= buf_size - HEADER_SIZE && i>= 0);
memcpy(s->last_buf + s->last_buf_size, s->gb.buffer + buf_size - HEADER_SIZE - i, i);
s->last_buf_size += i;
break;
}
/* apply the synthesis filter */
for(ch=0;ch<s->nb_channels;ch++) {
samples_ptr = samples + ch;
for(i=0;i<nb_frames;i++) {
ff_mpa_synth_filter(s->synth_buf[ch], &(s->synth_buf_offset[ch]),
window, &s->dither_state,
samples_ptr, s->nb_channels,
s->sb_samples[ch][i]);
samples_ptr += 32 * s->nb_channels;
}
}
return nb_frames * 32 * sizeof(OUT_INT) * s->nb_channels;
}
static int decode_frame(AVCodecContext * avctx,
void *data, int *data_size,
const uint8_t * buf, int buf_size)
{
MPADecodeContext *s = avctx->priv_data;
uint32_t header;
int out_size;
OUT_INT *out_samples = data;
retry: