3
* Copyright (c) 2001, 2002 Fabrice Bellard.
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* This library is free software; you can redistribute it and/or
6
* modify it under the terms of the GNU Lesser General Public
7
* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13
* Lesser General Public License for more details.
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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* @file mpegaudiodec.c
27
#include "bitstream.h"
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* - in low precision mode, use more 16 bit multiplies in synth filter
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* - test lsf / mpeg25 extensively.
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/* define USE_HIGHPRECISION to have a bit exact (but slower) mpeg
38
#ifdef CONFIG_MPEGAUDIO_HP
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#define USE_HIGHPRECISION
42
#include "mpegaudio.h"
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#define FRAC_ONE (1 << FRAC_BITS)
46
#define MULL(a,b) (((int64_t)(a) * (int64_t)(b)) >> FRAC_BITS)
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#define MUL64(a,b) ((int64_t)(a) * (int64_t)(b))
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#define FIX(a) ((int)((a) * FRAC_ONE))
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/* WARNING: only correct for posititive numbers */
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#define FIXR(a) ((int)((a) * FRAC_ONE + 0.5))
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#define FRAC_RND(a) (((a) + (FRAC_ONE/2)) >> FRAC_BITS)
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#define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5))
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//#define MULH(a,b) (((int64_t)(a) * (int64_t)(b))>>32) //gcc 3.4 creates an incredibly bloated mess out of this
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static always_inline int MULH(int a, int b){
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return ((int64_t)(a) * (int64_t)(b))>>32;
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#define BACKSTEP_SIZE 512
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typedef struct MPADecodeContext {
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uint8_t inbuf1[2][MPA_MAX_CODED_FRAME_SIZE + BACKSTEP_SIZE]; /* input buffer */
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uint8_t *inbuf_ptr, *inbuf;
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int free_format_frame_size; /* frame size in case of free format
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(zero if currently unknown) */
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/* next header (used in free format parsing) */
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uint32_t free_format_next_header;
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int sample_rate_index; /* between 0 and 8 */
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MPA_INT synth_buf[MPA_MAX_CHANNELS][512 * 2] __attribute__((aligned(16)));
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int synth_buf_offset[MPA_MAX_CHANNELS];
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int32_t sb_samples[MPA_MAX_CHANNELS][36][SBLIMIT] __attribute__((aligned(16)));
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int32_t mdct_buf[MPA_MAX_CHANNELS][SBLIMIT * 18]; /* previous samples, for layer 3 MDCT */
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void (*compute_antialias)(struct MPADecodeContext *s, struct GranuleDef *g);
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int adu_mode; ///< 0 for standard mp3, 1 for adu formatted mp3
95
unsigned int dither_state;
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* Context for MP3On4 decoder
101
typedef struct MP3On4DecodeContext {
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int frames; ///< number of mp3 frames per block (number of mp3 decoder instances)
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int chan_cfg; ///< channel config number
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MPADecodeContext *mp3decctx[5]; ///< MPADecodeContext for every decoder instance
105
} MP3On4DecodeContext;
107
/* layer 3 "granule" */
108
typedef struct GranuleDef {
113
int scalefac_compress;
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uint8_t switch_point;
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int subblock_gain[3];
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uint8_t scalefac_scale;
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uint8_t count1table_select;
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int region_size[3]; /* number of huffman codes in each region */
122
int short_start, long_end; /* long/short band indexes */
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uint8_t scale_factors[40];
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int32_t sb_hybrid[SBLIMIT * 18]; /* 576 samples */
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#define MODE_EXT_MS_STEREO 2
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#define MODE_EXT_I_STEREO 1
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/* layer 3 huffman tables */
131
typedef struct HuffTable {
134
const uint16_t *codes;
137
#include "mpegaudiodectab.h"
139
static void compute_antialias_integer(MPADecodeContext *s, GranuleDef *g);
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static void compute_antialias_float(MPADecodeContext *s, GranuleDef *g);
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/* vlc structure for decoding layer 3 huffman tables */
143
static VLC huff_vlc[16];
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static uint8_t *huff_code_table[16];
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static VLC huff_quad_vlc[2];
146
/* computed from band_size_long */
147
static uint16_t band_index_long[9][23];
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/* XXX: free when all decoders are closed */
149
#define TABLE_4_3_SIZE (8191 + 16)*4
150
static int8_t *table_4_3_exp;
151
static uint32_t *table_4_3_value;
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/* intensity stereo coef table */
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static int32_t is_table[2][16];
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static int32_t is_table_lsf[2][2][16];
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static int32_t csa_table[8][4];
156
static float csa_table_float[8][4];
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static int32_t mdct_win[8][36];
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/* lower 2 bits: modulo 3, higher bits: shift */
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static uint16_t scale_factor_modshift[64];
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/* [i][j]: 2^(-j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2) - 1) */
162
static int32_t scale_factor_mult[15][3];
163
/* mult table for layer 2 group quantization */
165
#define SCALE_GEN(v) \
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{ FIXR(1.0 * (v)), FIXR(0.7937005259 * (v)), FIXR(0.6299605249 * (v)) }
168
static const int32_t scale_factor_mult2[3][3] = {
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SCALE_GEN(4.0 / 3.0), /* 3 steps */
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SCALE_GEN(4.0 / 5.0), /* 5 steps */
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SCALE_GEN(4.0 / 9.0), /* 9 steps */
174
void ff_mpa_synth_init(MPA_INT *window);
175
static MPA_INT window[512] __attribute__((aligned(16)));
177
/* layer 1 unscaling */
178
/* n = number of bits of the mantissa minus 1 */
179
static inline int l1_unscale(int n, int mant, int scale_factor)
184
shift = scale_factor_modshift[scale_factor];
187
val = MUL64(mant + (-1 << n) + 1, scale_factor_mult[n-1][mod]);
189
/* NOTE: at this point, 1 <= shift >= 21 + 15 */
190
return (int)((val + (1LL << (shift - 1))) >> shift);
193
static inline int l2_unscale_group(int steps, int mant, int scale_factor)
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shift = scale_factor_modshift[scale_factor];
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val = (mant - (steps >> 1)) * scale_factor_mult2[steps >> 2][mod];
202
/* NOTE: at this point, 0 <= shift <= 21 */
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val = (val + (1 << (shift - 1))) >> shift;
208
/* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */
209
static inline int l3_unscale(int value, int exponent)
214
e = table_4_3_exp [4*value + (exponent&3)];
215
m = table_4_3_value[4*value + (exponent&3)];
216
e -= (exponent >> 2);
220
m = (m + (1 << (e-1))) >> e;
225
/* all integer n^(4/3) computation code */
228
#define POW_FRAC_BITS 24
229
#define POW_FRAC_ONE (1 << POW_FRAC_BITS)
230
#define POW_FIX(a) ((int)((a) * POW_FRAC_ONE))
231
#define POW_MULL(a,b) (((int64_t)(a) * (int64_t)(b)) >> POW_FRAC_BITS)
233
static int dev_4_3_coefs[DEV_ORDER];
236
static int pow_mult3[3] = {
238
POW_FIX(1.25992104989487316476),
239
POW_FIX(1.58740105196819947474),
243
static void int_pow_init(void)
248
for(i=0;i<DEV_ORDER;i++) {
249
a = POW_MULL(a, POW_FIX(4.0 / 3.0) - i * POW_FIX(1.0)) / (i + 1);
250
dev_4_3_coefs[i] = a;
254
#if 0 /* unused, remove? */
255
/* return the mantissa and the binary exponent */
256
static int int_pow(int i, int *exp_ptr)
264
while (a < (1 << (POW_FRAC_BITS - 1))) {
268
a -= (1 << POW_FRAC_BITS);
270
for(j = DEV_ORDER - 1; j >= 0; j--)
271
a1 = POW_MULL(a, dev_4_3_coefs[j] + a1);
272
a = (1 << POW_FRAC_BITS) + a1;
273
/* exponent compute (exact) */
277
a = POW_MULL(a, pow_mult3[er]);
278
while (a >= 2 * POW_FRAC_ONE) {
282
/* convert to float */
283
while (a < POW_FRAC_ONE) {
287
/* now POW_FRAC_ONE <= a < 2 * POW_FRAC_ONE */
288
#if POW_FRAC_BITS > FRAC_BITS
289
a = (a + (1 << (POW_FRAC_BITS - FRAC_BITS - 1))) >> (POW_FRAC_BITS - FRAC_BITS);
290
/* correct overflow */
291
if (a >= 2 * (1 << FRAC_BITS)) {
301
static int decode_init(AVCodecContext * avctx)
303
MPADecodeContext *s = avctx->priv_data;
307
#if defined(USE_HIGHPRECISION) && defined(CONFIG_AUDIO_NONSHORT)
308
avctx->sample_fmt= SAMPLE_FMT_S32;
310
avctx->sample_fmt= SAMPLE_FMT_S16;
313
if(avctx->antialias_algo != FF_AA_FLOAT)
314
s->compute_antialias= compute_antialias_integer;
316
s->compute_antialias= compute_antialias_float;
318
if (!init && !avctx->parse_only) {
319
/* scale factors table for layer 1/2 */
322
/* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */
325
scale_factor_modshift[i] = mod | (shift << 2);
328
/* scale factor multiply for layer 1 */
332
norm = ((int64_t_C(1) << n) * FRAC_ONE) / ((1 << n) - 1);
333
scale_factor_mult[i][0] = MULL(FIXR(1.0 * 2.0), norm);
334
scale_factor_mult[i][1] = MULL(FIXR(0.7937005259 * 2.0), norm);
335
scale_factor_mult[i][2] = MULL(FIXR(0.6299605249 * 2.0), norm);
336
dprintf("%d: norm=%x s=%x %x %x\n",
338
scale_factor_mult[i][0],
339
scale_factor_mult[i][1],
340
scale_factor_mult[i][2]);
343
ff_mpa_synth_init(window);
345
/* huffman decode tables */
346
huff_code_table[0] = NULL;
348
const HuffTable *h = &mpa_huff_tables[i];
356
init_vlc(&huff_vlc[i], 8, n,
357
h->bits, 1, 1, h->codes, 2, 2, 1);
359
code_table = av_mallocz(n);
361
for(x=0;x<xsize;x++) {
363
code_table[j++] = (x << 4) | y;
365
huff_code_table[i] = code_table;
368
init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16,
369
mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1, 1);
375
band_index_long[i][j] = k;
376
k += band_size_long[i][j];
378
band_index_long[i][22] = k;
381
/* compute n ^ (4/3) and store it in mantissa/exp format */
382
table_4_3_exp= av_mallocz_static(TABLE_4_3_SIZE * sizeof(table_4_3_exp[0]));
385
table_4_3_value= av_mallocz_static(TABLE_4_3_SIZE * sizeof(table_4_3_value[0]));
390
for(i=1;i<TABLE_4_3_SIZE;i++) {
393
f = pow((double)(i/4), 4.0 / 3.0) * pow(2, (i&3)*0.25);
395
m = (uint32_t)(fm*(1LL<<31) + 0.5);
396
e+= FRAC_BITS - 31 + 5;
398
/* normalized to FRAC_BITS */
399
table_4_3_value[i] = m;
400
// av_log(NULL, AV_LOG_DEBUG, "%d %d %f\n", i, m, pow((double)i, 4.0 / 3.0));
401
table_4_3_exp[i] = -e;
408
f = tan((double)i * M_PI / 12.0);
409
v = FIXR(f / (1.0 + f));
414
is_table[1][6 - i] = v;
418
is_table[0][i] = is_table[1][i] = 0.0;
425
e = -(j + 1) * ((i + 1) >> 1);
426
f = pow(2.0, e / 4.0);
428
is_table_lsf[j][k ^ 1][i] = FIXR(f);
429
is_table_lsf[j][k][i] = FIXR(1.0);
430
dprintf("is_table_lsf %d %d: %x %x\n",
431
i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]);
438
cs = 1.0 / sqrt(1.0 + ci * ci);
440
csa_table[i][0] = FIXHR(cs/4);
441
csa_table[i][1] = FIXHR(ca/4);
442
csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4);
443
csa_table[i][3] = FIXHR(ca/4) - FIXHR(cs/4);
444
csa_table_float[i][0] = cs;
445
csa_table_float[i][1] = ca;
446
csa_table_float[i][2] = ca + cs;
447
csa_table_float[i][3] = ca - cs;
448
// printf("%d %d %d %d\n", FIX(cs), FIX(cs-1), FIX(ca), FIX(cs)-FIX(ca));
449
// av_log(NULL, AV_LOG_DEBUG,"%f %f %f %f\n", cs, ca, ca+cs, ca-cs);
452
/* compute mdct windows */
460
d= sin(M_PI * (i + 0.5) / 36.0);
463
else if(i>=24) d= sin(M_PI * (i - 18 + 0.5) / 12.0);
467
else if(i< 12) d= sin(M_PI * (i - 6 + 0.5) / 12.0);
470
//merge last stage of imdct into the window coefficients
471
d*= 0.5 / cos(M_PI*(2*i + 19)/72);
474
mdct_win[j][i/3] = FIXHR((d / (1<<5)));
476
mdct_win[j][i ] = FIXHR((d / (1<<5)));
477
// av_log(NULL, AV_LOG_DEBUG, "%2d %d %f\n", i,j,d / (1<<5));
481
/* NOTE: we do frequency inversion adter the MDCT by changing
482
the sign of the right window coefs */
485
mdct_win[j + 4][i] = mdct_win[j][i];
486
mdct_win[j + 4][i + 1] = -mdct_win[j][i + 1];
492
av_log(avctx, AV_LOG_DEBUG, "win%d=\n", j);
494
av_log(avctx, AV_LOG_DEBUG, "%f, ", (double)mdct_win[j][i] / FRAC_ONE);
495
av_log(avctx, AV_LOG_DEBUG, "\n");
502
s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE];
503
s->inbuf_ptr = s->inbuf;
507
if (avctx->codec_id == CODEC_ID_MP3ADU)
512
/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6 - j))) */
516
#define COS0_0 FIXR(0.50060299823519630134)
517
#define COS0_1 FIXR(0.50547095989754365998)
518
#define COS0_2 FIXR(0.51544730992262454697)
519
#define COS0_3 FIXR(0.53104259108978417447)
520
#define COS0_4 FIXR(0.55310389603444452782)
521
#define COS0_5 FIXR(0.58293496820613387367)
522
#define COS0_6 FIXR(0.62250412303566481615)
523
#define COS0_7 FIXR(0.67480834145500574602)
524
#define COS0_8 FIXR(0.74453627100229844977)
525
#define COS0_9 FIXR(0.83934964541552703873)
526
#define COS0_10 FIXR(0.97256823786196069369)
527
#define COS0_11 FIXR(1.16943993343288495515)
528
#define COS0_12 FIXR(1.48416461631416627724)
529
#define COS0_13 FIXR(2.05778100995341155085)
530
#define COS0_14 FIXR(3.40760841846871878570)
531
#define COS0_15 FIXR(10.19000812354805681150)
533
#define COS1_0 FIXR(0.50241928618815570551)
534
#define COS1_1 FIXR(0.52249861493968888062)
535
#define COS1_2 FIXR(0.56694403481635770368)
536
#define COS1_3 FIXR(0.64682178335999012954)
537
#define COS1_4 FIXR(0.78815462345125022473)
538
#define COS1_5 FIXR(1.06067768599034747134)
539
#define COS1_6 FIXR(1.72244709823833392782)
540
#define COS1_7 FIXR(5.10114861868916385802)
542
#define COS2_0 FIXR(0.50979557910415916894)
543
#define COS2_1 FIXR(0.60134488693504528054)
544
#define COS2_2 FIXR(0.89997622313641570463)
545
#define COS2_3 FIXR(2.56291544774150617881)
547
#define COS3_0 FIXR(0.54119610014619698439)
548
#define COS3_1 FIXR(1.30656296487637652785)
550
#define COS4_0 FIXR(0.70710678118654752439)
552
/* butterfly operator */
555
tmp0 = tab[a] + tab[b];\
556
tmp1 = tab[a] - tab[b];\
558
tab[b] = MULL(tmp1, c);\
561
#define BF1(a, b, c, d)\
568
#define BF2(a, b, c, d)\
578
#define ADD(a, b) tab[a] += tab[b]
580
/* DCT32 without 1/sqrt(2) coef zero scaling. */
581
static void dct32(int32_t *out, int32_t *tab)
713
out[ 1] = tab[16] + tab[24];
714
out[17] = tab[17] + tab[25];
715
out[ 9] = tab[18] + tab[26];
716
out[25] = tab[19] + tab[27];
717
out[ 5] = tab[20] + tab[28];
718
out[21] = tab[21] + tab[29];
719
out[13] = tab[22] + tab[30];
720
out[29] = tab[23] + tab[31];
721
out[ 3] = tab[24] + tab[20];
722
out[19] = tab[25] + tab[21];
723
out[11] = tab[26] + tab[22];
724
out[27] = tab[27] + tab[23];
725
out[ 7] = tab[28] + tab[18];
726
out[23] = tab[29] + tab[19];
727
out[15] = tab[30] + tab[17];
733
static inline int round_sample(int *sum)
736
sum1 = (*sum) >> OUT_SHIFT;
737
*sum &= (1<<OUT_SHIFT)-1;
740
else if (sum1 > OUT_MAX)
745
#if defined(ARCH_POWERPC_405)
747
/* signed 16x16 -> 32 multiply add accumulate */
748
#define MACS(rt, ra, rb) \
749
asm ("maclhw %0, %2, %3" : "=r" (rt) : "0" (rt), "r" (ra), "r" (rb));
751
/* signed 16x16 -> 32 multiply */
752
#define MULS(ra, rb) \
753
({ int __rt; asm ("mullhw %0, %1, %2" : "=r" (__rt) : "r" (ra), "r" (rb)); __rt; })
757
/* signed 16x16 -> 32 multiply add accumulate */
758
#define MACS(rt, ra, rb) rt += (ra) * (rb)
760
/* signed 16x16 -> 32 multiply */
761
#define MULS(ra, rb) ((ra) * (rb))
767
static inline int round_sample(int64_t *sum)
770
sum1 = (int)((*sum) >> OUT_SHIFT);
771
*sum &= (1<<OUT_SHIFT)-1;
774
else if (sum1 > OUT_MAX)
779
#define MULS(ra, rb) MUL64(ra, rb)
783
#define SUM8(sum, op, w, p) \
785
sum op MULS((w)[0 * 64], p[0 * 64]);\
786
sum op MULS((w)[1 * 64], p[1 * 64]);\
787
sum op MULS((w)[2 * 64], p[2 * 64]);\
788
sum op MULS((w)[3 * 64], p[3 * 64]);\
789
sum op MULS((w)[4 * 64], p[4 * 64]);\
790
sum op MULS((w)[5 * 64], p[5 * 64]);\
791
sum op MULS((w)[6 * 64], p[6 * 64]);\
792
sum op MULS((w)[7 * 64], p[7 * 64]);\
795
#define SUM8P2(sum1, op1, sum2, op2, w1, w2, p) \
799
sum1 op1 MULS((w1)[0 * 64], tmp);\
800
sum2 op2 MULS((w2)[0 * 64], tmp);\
802
sum1 op1 MULS((w1)[1 * 64], tmp);\
803
sum2 op2 MULS((w2)[1 * 64], tmp);\
805
sum1 op1 MULS((w1)[2 * 64], tmp);\
806
sum2 op2 MULS((w2)[2 * 64], tmp);\
808
sum1 op1 MULS((w1)[3 * 64], tmp);\
809
sum2 op2 MULS((w2)[3 * 64], tmp);\
811
sum1 op1 MULS((w1)[4 * 64], tmp);\
812
sum2 op2 MULS((w2)[4 * 64], tmp);\
814
sum1 op1 MULS((w1)[5 * 64], tmp);\
815
sum2 op2 MULS((w2)[5 * 64], tmp);\
817
sum1 op1 MULS((w1)[6 * 64], tmp);\
818
sum2 op2 MULS((w2)[6 * 64], tmp);\
820
sum1 op1 MULS((w1)[7 * 64], tmp);\
821
sum2 op2 MULS((w2)[7 * 64], tmp);\
824
void ff_mpa_synth_init(MPA_INT *window)
828
/* max = 18760, max sum over all 16 coefs : 44736 */
833
v = (v + (1 << (16 - WFRAC_BITS - 1))) >> (16 - WFRAC_BITS);
843
/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:
845
/* XXX: optimize by avoiding ring buffer usage */
846
void ff_mpa_synth_filter(MPA_INT *synth_buf_ptr, int *synth_buf_offset,
847
MPA_INT *window, int *dither_state,
848
OUT_INT *samples, int incr,
849
int32_t sb_samples[SBLIMIT])
852
register MPA_INT *synth_buf;
853
register const MPA_INT *w, *w2, *p;
862
dct32(tmp, sb_samples);
864
offset = *synth_buf_offset;
865
synth_buf = synth_buf_ptr + offset;
870
/* NOTE: can cause a loss in precision if very high amplitude
879
/* copy to avoid wrap */
880
memcpy(synth_buf + 512, synth_buf, 32 * sizeof(MPA_INT));
882
samples2 = samples + 31 * incr;
890
SUM8(sum, -=, w + 32, p);
891
*samples = round_sample(&sum);
895
/* we calculate two samples at the same time to avoid one memory
896
access per two sample */
899
p = synth_buf + 16 + j;
900
SUM8P2(sum, +=, sum2, -=, w, w2, p);
901
p = synth_buf + 48 - j;
902
SUM8P2(sum, -=, sum2, -=, w + 32, w2 + 32, p);
904
*samples = round_sample(&sum);
907
*samples2 = round_sample(&sum);
914
SUM8(sum, -=, w + 32, p);
915
*samples = round_sample(&sum);
918
offset = (offset - 32) & 511;
919
*synth_buf_offset = offset;
922
#define C3 FIXHR(0.86602540378443864676/2)
924
/* 0.5 / cos(pi*(2*i+1)/36) */
925
static const int icos36[9] = {
926
FIXR(0.50190991877167369479),
927
FIXR(0.51763809020504152469), //0
928
FIXR(0.55168895948124587824),
929
FIXR(0.61038729438072803416),
930
FIXR(0.70710678118654752439), //1
931
FIXR(0.87172339781054900991),
932
FIXR(1.18310079157624925896),
933
FIXR(1.93185165257813657349), //2
934
FIXR(5.73685662283492756461),
937
/* 12 points IMDCT. We compute it "by hand" by factorizing obvious
939
static void imdct12(int *out, int *in)
941
int in0, in1, in2, in3, in4, in5, t1, t2;
944
in1= in[1*3] + in[0*3];
945
in2= in[2*3] + in[1*3];
946
in3= in[3*3] + in[2*3];
947
in4= in[4*3] + in[3*3];
948
in5= in[5*3] + in[4*3];
952
in2= MULH(2*in2, C3);
953
in3= MULH(2*in3, C3);
956
t2 = MULL(in1 - in5, icos36[4]);
966
in5 = MULL(in1 + in3, icos36[1]);
973
in1 = MULL(in1 - in3, icos36[7]);
981
#define C1 FIXHR(0.98480775301220805936/2)
982
#define C2 FIXHR(0.93969262078590838405/2)
983
#define C3 FIXHR(0.86602540378443864676/2)
984
#define C4 FIXHR(0.76604444311897803520/2)
985
#define C5 FIXHR(0.64278760968653932632/2)
986
#define C6 FIXHR(0.5/2)
987
#define C7 FIXHR(0.34202014332566873304/2)
988
#define C8 FIXHR(0.17364817766693034885/2)
991
/* using Lee like decomposition followed by hand coded 9 points DCT */
992
static void imdct36(int *out, int *buf, int *in, int *win)
994
int i, j, t0, t1, t2, t3, s0, s1, s2, s3;
995
int tmp[18], *tmp1, *in1;
1006
//more accurate but slower
1007
int64_t t0, t1, t2, t3;
1008
t2 = in1[2*4] + in1[2*8] - in1[2*2];
1010
t3 = (in1[2*0] + (int64_t)(in1[2*6]>>1))<<32;
1011
t1 = in1[2*0] - in1[2*6];
1012
tmp1[ 6] = t1 - (t2>>1);
1015
t0 = MUL64(2*(in1[2*2] + in1[2*4]), C2);
1016
t1 = MUL64( in1[2*4] - in1[2*8] , -2*C8);
1017
t2 = MUL64(2*(in1[2*2] + in1[2*8]), -C4);
1019
tmp1[10] = (t3 - t0 - t2) >> 32;
1020
tmp1[ 2] = (t3 + t0 + t1) >> 32;
1021
tmp1[14] = (t3 + t2 - t1) >> 32;
1023
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7] - in1[2*1]), -C3);
1024
t2 = MUL64(2*(in1[2*1] + in1[2*5]), C1);
1025
t3 = MUL64( in1[2*5] - in1[2*7] , -2*C7);
1026
t0 = MUL64(2*in1[2*3], C3);
1028
t1 = MUL64(2*(in1[2*1] + in1[2*7]), -C5);
1030
tmp1[ 0] = (t2 + t3 + t0) >> 32;
1031
tmp1[12] = (t2 + t1 - t0) >> 32;
1032
tmp1[ 8] = (t3 - t1 - t0) >> 32;
1034
t2 = in1[2*4] + in1[2*8] - in1[2*2];
1036
t3 = in1[2*0] + (in1[2*6]>>1);
1037
t1 = in1[2*0] - in1[2*6];
1038
tmp1[ 6] = t1 - (t2>>1);
1041
t0 = MULH(2*(in1[2*2] + in1[2*4]), C2);
1042
t1 = MULH( in1[2*4] - in1[2*8] , -2*C8);
1043
t2 = MULH(2*(in1[2*2] + in1[2*8]), -C4);
1045
tmp1[10] = t3 - t0 - t2;
1046
tmp1[ 2] = t3 + t0 + t1;
1047
tmp1[14] = t3 + t2 - t1;
1049
tmp1[ 4] = MULH(2*(in1[2*5] + in1[2*7] - in1[2*1]), -C3);
1050
t2 = MULH(2*(in1[2*1] + in1[2*5]), C1);
1051
t3 = MULH( in1[2*5] - in1[2*7] , -2*C7);
1052
t0 = MULH(2*in1[2*3], C3);
1054
t1 = MULH(2*(in1[2*1] + in1[2*7]), -C5);
1056
tmp1[ 0] = t2 + t3 + t0;
1057
tmp1[12] = t2 + t1 - t0;
1058
tmp1[ 8] = t3 - t1 - t0;
1071
s1 = MULL(t3 + t2, icos36[j]);
1072
s3 = MULL(t3 - t2, icos36[8 - j]);
1076
out[(9 + j)*SBLIMIT] = MULH(t1, win[9 + j]) + buf[9 + j];
1077
out[(8 - j)*SBLIMIT] = MULH(t1, win[8 - j]) + buf[8 - j];
1078
buf[9 + j] = MULH(t0, win[18 + 9 + j]);
1079
buf[8 - j] = MULH(t0, win[18 + 8 - j]);
1083
out[(9 + 8 - j)*SBLIMIT] = MULH(t1, win[9 + 8 - j]) + buf[9 + 8 - j];
1084
out[( j)*SBLIMIT] = MULH(t1, win[ j]) + buf[ j];
1085
buf[9 + 8 - j] = MULH(t0, win[18 + 9 + 8 - j]);
1086
buf[ + j] = MULH(t0, win[18 + j]);
1091
s1 = MULL(tmp[17], icos36[4]);
1094
out[(9 + 4)*SBLIMIT] = MULH(t1, win[9 + 4]) + buf[9 + 4];
1095
out[(8 - 4)*SBLIMIT] = MULH(t1, win[8 - 4]) + buf[8 - 4];
1096
buf[9 + 4] = MULH(t0, win[18 + 9 + 4]);
1097
buf[8 - 4] = MULH(t0, win[18 + 8 - 4]);
1100
/* header decoding. MUST check the header before because no
1101
consistency check is done there. Return 1 if free format found and
1102
that the frame size must be computed externally */
1103
static int decode_header(MPADecodeContext *s, uint32_t header)
1105
int sample_rate, frame_size, mpeg25, padding;
1106
int sample_rate_index, bitrate_index;
1107
if (header & (1<<20)) {
1108
s->lsf = (header & (1<<19)) ? 0 : 1;
1115
s->layer = 4 - ((header >> 17) & 3);
1116
/* extract frequency */
1117
sample_rate_index = (header >> 10) & 3;
1118
sample_rate = mpa_freq_tab[sample_rate_index] >> (s->lsf + mpeg25);
1119
sample_rate_index += 3 * (s->lsf + mpeg25);
1120
s->sample_rate_index = sample_rate_index;
1121
s->error_protection = ((header >> 16) & 1) ^ 1;
1122
s->sample_rate = sample_rate;
1124
bitrate_index = (header >> 12) & 0xf;
1125
padding = (header >> 9) & 1;
1126
//extension = (header >> 8) & 1;
1127
s->mode = (header >> 6) & 3;
1128
s->mode_ext = (header >> 4) & 3;
1129
//copyright = (header >> 3) & 1;
1130
//original = (header >> 2) & 1;
1131
//emphasis = header & 3;
1133
if (s->mode == MPA_MONO)
1138
if (bitrate_index != 0) {
1139
frame_size = mpa_bitrate_tab[s->lsf][s->layer - 1][bitrate_index];
1140
s->bit_rate = frame_size * 1000;
1143
frame_size = (frame_size * 12000) / sample_rate;
1144
frame_size = (frame_size + padding) * 4;
1147
frame_size = (frame_size * 144000) / sample_rate;
1148
frame_size += padding;
1152
frame_size = (frame_size * 144000) / (sample_rate << s->lsf);
1153
frame_size += padding;
1156
s->frame_size = frame_size;
1158
/* if no frame size computed, signal it */
1159
if (!s->free_format_frame_size)
1161
/* free format: compute bitrate and real frame size from the
1162
frame size we extracted by reading the bitstream */
1163
s->frame_size = s->free_format_frame_size;
1166
s->frame_size += padding * 4;
1167
s->bit_rate = (s->frame_size * sample_rate) / 48000;
1170
s->frame_size += padding;
1171
s->bit_rate = (s->frame_size * sample_rate) / 144000;
1175
s->frame_size += padding;
1176
s->bit_rate = (s->frame_size * (sample_rate << s->lsf)) / 144000;
1182
dprintf("layer%d, %d Hz, %d kbits/s, ",
1183
s->layer, s->sample_rate, s->bit_rate);
1184
if (s->nb_channels == 2) {
1185
if (s->layer == 3) {
1186
if (s->mode_ext & MODE_EXT_MS_STEREO)
1188
if (s->mode_ext & MODE_EXT_I_STEREO)
1200
/* useful helper to get mpeg audio stream infos. Return -1 if error in
1201
header, otherwise the coded frame size in bytes */
1202
int mpa_decode_header(AVCodecContext *avctx, uint32_t head)
1204
MPADecodeContext s1, *s = &s1;
1205
memset( s, 0, sizeof(MPADecodeContext) );
1207
if (ff_mpa_check_header(head) != 0)
1210
if (decode_header(s, head) != 0) {
1216
avctx->frame_size = 384;
1219
avctx->frame_size = 1152;
1224
avctx->frame_size = 576;
1226
avctx->frame_size = 1152;
1230
avctx->sample_rate = s->sample_rate;
1231
avctx->channels = s->nb_channels;
1232
avctx->bit_rate = s->bit_rate;
1233
avctx->sub_id = s->layer;
1234
return s->frame_size;
1237
/* return the number of decoded frames */
1238
static int mp_decode_layer1(MPADecodeContext *s)
1240
int bound, i, v, n, ch, j, mant;
1241
uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT];
1242
uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT];
1244
if (s->mode == MPA_JSTEREO)
1245
bound = (s->mode_ext + 1) * 4;
1249
/* allocation bits */
1250
for(i=0;i<bound;i++) {
1251
for(ch=0;ch<s->nb_channels;ch++) {
1252
allocation[ch][i] = get_bits(&s->gb, 4);
1255
for(i=bound;i<SBLIMIT;i++) {
1256
allocation[0][i] = get_bits(&s->gb, 4);
1260
for(i=0;i<bound;i++) {
1261
for(ch=0;ch<s->nb_channels;ch++) {
1262
if (allocation[ch][i])
1263
scale_factors[ch][i] = get_bits(&s->gb, 6);
1266
for(i=bound;i<SBLIMIT;i++) {
1267
if (allocation[0][i]) {
1268
scale_factors[0][i] = get_bits(&s->gb, 6);
1269
scale_factors[1][i] = get_bits(&s->gb, 6);
1273
/* compute samples */
1275
for(i=0;i<bound;i++) {
1276
for(ch=0;ch<s->nb_channels;ch++) {
1277
n = allocation[ch][i];
1279
mant = get_bits(&s->gb, n + 1);
1280
v = l1_unscale(n, mant, scale_factors[ch][i]);
1284
s->sb_samples[ch][j][i] = v;
1287
for(i=bound;i<SBLIMIT;i++) {
1288
n = allocation[0][i];
1290
mant = get_bits(&s->gb, n + 1);
1291
v = l1_unscale(n, mant, scale_factors[0][i]);
1292
s->sb_samples[0][j][i] = v;
1293
v = l1_unscale(n, mant, scale_factors[1][i]);
1294
s->sb_samples[1][j][i] = v;
1296
s->sb_samples[0][j][i] = 0;
1297
s->sb_samples[1][j][i] = 0;
1304
/* bitrate is in kb/s */
1305
int l2_select_table(int bitrate, int nb_channels, int freq, int lsf)
1307
int ch_bitrate, table;
1309
ch_bitrate = bitrate / nb_channels;
1311
if ((freq == 48000 && ch_bitrate >= 56) ||
1312
(ch_bitrate >= 56 && ch_bitrate <= 80))
1314
else if (freq != 48000 && ch_bitrate >= 96)
1316
else if (freq != 32000 && ch_bitrate <= 48)
1326
static int mp_decode_layer2(MPADecodeContext *s)
1328
int sblimit; /* number of used subbands */
1329
const unsigned char *alloc_table;
1330
int table, bit_alloc_bits, i, j, ch, bound, v;
1331
unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT];
1332
unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];
1333
unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf;
1334
int scale, qindex, bits, steps, k, l, m, b;
1336
/* select decoding table */
1337
table = l2_select_table(s->bit_rate / 1000, s->nb_channels,
1338
s->sample_rate, s->lsf);
1339
sblimit = sblimit_table[table];
1340
alloc_table = alloc_tables[table];
1342
if (s->mode == MPA_JSTEREO)
1343
bound = (s->mode_ext + 1) * 4;
1347
dprintf("bound=%d sblimit=%d\n", bound, sblimit);
1350
if( bound > sblimit ) bound = sblimit;
1352
/* parse bit allocation */
1354
for(i=0;i<bound;i++) {
1355
bit_alloc_bits = alloc_table[j];
1356
for(ch=0;ch<s->nb_channels;ch++) {
1357
bit_alloc[ch][i] = get_bits(&s->gb, bit_alloc_bits);
1359
j += 1 << bit_alloc_bits;
1361
for(i=bound;i<sblimit;i++) {
1362
bit_alloc_bits = alloc_table[j];
1363
v = get_bits(&s->gb, bit_alloc_bits);
1364
bit_alloc[0][i] = v;
1365
bit_alloc[1][i] = v;
1366
j += 1 << bit_alloc_bits;
1371
for(ch=0;ch<s->nb_channels;ch++) {
1372
for(i=0;i<sblimit;i++)
1373
dprintf(" %d", bit_alloc[ch][i]);
1380
for(i=0;i<sblimit;i++) {
1381
for(ch=0;ch<s->nb_channels;ch++) {
1382
if (bit_alloc[ch][i])
1383
scale_code[ch][i] = get_bits(&s->gb, 2);
1388
for(i=0;i<sblimit;i++) {
1389
for(ch=0;ch<s->nb_channels;ch++) {
1390
if (bit_alloc[ch][i]) {
1391
sf = scale_factors[ch][i];
1392
switch(scale_code[ch][i]) {
1395
sf[0] = get_bits(&s->gb, 6);
1396
sf[1] = get_bits(&s->gb, 6);
1397
sf[2] = get_bits(&s->gb, 6);
1400
sf[0] = get_bits(&s->gb, 6);
1405
sf[0] = get_bits(&s->gb, 6);
1406
sf[2] = get_bits(&s->gb, 6);
1410
sf[0] = get_bits(&s->gb, 6);
1411
sf[2] = get_bits(&s->gb, 6);
1420
for(ch=0;ch<s->nb_channels;ch++) {
1421
for(i=0;i<sblimit;i++) {
1422
if (bit_alloc[ch][i]) {
1423
sf = scale_factors[ch][i];
1424
dprintf(" %d %d %d", sf[0], sf[1], sf[2]);
1435
for(l=0;l<12;l+=3) {
1437
for(i=0;i<bound;i++) {
1438
bit_alloc_bits = alloc_table[j];
1439
for(ch=0;ch<s->nb_channels;ch++) {
1440
b = bit_alloc[ch][i];
1442
scale = scale_factors[ch][i][k];
1443
qindex = alloc_table[j+b];
1444
bits = quant_bits[qindex];
1446
/* 3 values at the same time */
1447
v = get_bits(&s->gb, -bits);
1448
steps = quant_steps[qindex];
1449
s->sb_samples[ch][k * 12 + l + 0][i] =
1450
l2_unscale_group(steps, v % steps, scale);
1452
s->sb_samples[ch][k * 12 + l + 1][i] =
1453
l2_unscale_group(steps, v % steps, scale);
1455
s->sb_samples[ch][k * 12 + l + 2][i] =
1456
l2_unscale_group(steps, v, scale);
1459
v = get_bits(&s->gb, bits);
1460
v = l1_unscale(bits - 1, v, scale);
1461
s->sb_samples[ch][k * 12 + l + m][i] = v;
1465
s->sb_samples[ch][k * 12 + l + 0][i] = 0;
1466
s->sb_samples[ch][k * 12 + l + 1][i] = 0;
1467
s->sb_samples[ch][k * 12 + l + 2][i] = 0;
1470
/* next subband in alloc table */
1471
j += 1 << bit_alloc_bits;
1473
/* XXX: find a way to avoid this duplication of code */
1474
for(i=bound;i<sblimit;i++) {
1475
bit_alloc_bits = alloc_table[j];
1476
b = bit_alloc[0][i];
1478
int mant, scale0, scale1;
1479
scale0 = scale_factors[0][i][k];
1480
scale1 = scale_factors[1][i][k];
1481
qindex = alloc_table[j+b];
1482
bits = quant_bits[qindex];
1484
/* 3 values at the same time */
1485
v = get_bits(&s->gb, -bits);
1486
steps = quant_steps[qindex];
1489
s->sb_samples[0][k * 12 + l + 0][i] =
1490
l2_unscale_group(steps, mant, scale0);
1491
s->sb_samples[1][k * 12 + l + 0][i] =
1492
l2_unscale_group(steps, mant, scale1);
1495
s->sb_samples[0][k * 12 + l + 1][i] =
1496
l2_unscale_group(steps, mant, scale0);
1497
s->sb_samples[1][k * 12 + l + 1][i] =
1498
l2_unscale_group(steps, mant, scale1);
1499
s->sb_samples[0][k * 12 + l + 2][i] =
1500
l2_unscale_group(steps, v, scale0);
1501
s->sb_samples[1][k * 12 + l + 2][i] =
1502
l2_unscale_group(steps, v, scale1);
1505
mant = get_bits(&s->gb, bits);
1506
s->sb_samples[0][k * 12 + l + m][i] =
1507
l1_unscale(bits - 1, mant, scale0);
1508
s->sb_samples[1][k * 12 + l + m][i] =
1509
l1_unscale(bits - 1, mant, scale1);
1513
s->sb_samples[0][k * 12 + l + 0][i] = 0;
1514
s->sb_samples[0][k * 12 + l + 1][i] = 0;
1515
s->sb_samples[0][k * 12 + l + 2][i] = 0;
1516
s->sb_samples[1][k * 12 + l + 0][i] = 0;
1517
s->sb_samples[1][k * 12 + l + 1][i] = 0;
1518
s->sb_samples[1][k * 12 + l + 2][i] = 0;
1520
/* next subband in alloc table */
1521
j += 1 << bit_alloc_bits;
1523
/* fill remaining samples to zero */
1524
for(i=sblimit;i<SBLIMIT;i++) {
1525
for(ch=0;ch<s->nb_channels;ch++) {
1526
s->sb_samples[ch][k * 12 + l + 0][i] = 0;
1527
s->sb_samples[ch][k * 12 + l + 1][i] = 0;
1528
s->sb_samples[ch][k * 12 + l + 2][i] = 0;
1537
* Seek back in the stream for backstep bytes (at most 511 bytes)
1539
static void seek_to_maindata(MPADecodeContext *s, unsigned int backstep)
1543
/* compute current position in stream */
1544
ptr = (uint8_t *)(s->gb.buffer + (get_bits_count(&s->gb)>>3));
1546
/* copy old data before current one */
1548
memcpy(ptr, s->inbuf1[s->inbuf_index ^ 1] +
1549
BACKSTEP_SIZE + s->old_frame_size - backstep, backstep);
1550
/* init get bits again */
1551
init_get_bits(&s->gb, ptr, (s->frame_size + backstep)*8);
1553
/* prepare next buffer */
1554
s->inbuf_index ^= 1;
1555
s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE];
1556
s->old_frame_size = s->frame_size;
1559
static inline void lsf_sf_expand(int *slen,
1560
int sf, int n1, int n2, int n3)
1579
static void exponents_from_scale_factors(MPADecodeContext *s,
1583
const uint8_t *bstab, *pretab;
1584
int len, i, j, k, l, v0, shift, gain, gains[3];
1587
exp_ptr = exponents;
1588
gain = g->global_gain - 210;
1589
shift = g->scalefac_scale + 1;
1591
bstab = band_size_long[s->sample_rate_index];
1592
pretab = mpa_pretab[g->preflag];
1593
for(i=0;i<g->long_end;i++) {
1594
v0 = gain - ((g->scale_factors[i] + pretab[i]) << shift);
1600
if (g->short_start < 13) {
1601
bstab = band_size_short[s->sample_rate_index];
1602
gains[0] = gain - (g->subblock_gain[0] << 3);
1603
gains[1] = gain - (g->subblock_gain[1] << 3);
1604
gains[2] = gain - (g->subblock_gain[2] << 3);
1606
for(i=g->short_start;i<13;i++) {
1609
v0 = gains[l] - (g->scale_factors[k++] << shift);
1617
/* handle n = 0 too */
1618
static inline int get_bitsz(GetBitContext *s, int n)
1623
return get_bits(s, n);
1626
static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
1627
int16_t *exponents, int end_pos)
1630
int linbits, code, x, y, l, v, i, j, k, pos;
1631
GetBitContext last_gb;
1633
uint8_t *code_table;
1635
/* low frequencies (called big values) */
1638
j = g->region_size[i];
1641
/* select vlc table */
1642
k = g->table_select[i];
1643
l = mpa_huff_data[k][0];
1644
linbits = mpa_huff_data[k][1];
1646
code_table = huff_code_table[l];
1648
/* read huffcode and compute each couple */
1650
if (get_bits_count(&s->gb) >= end_pos)
1653
code = get_vlc2(&s->gb, vlc->table, 8, 3);
1656
y = code_table[code];
1663
dprintf("region=%d n=%d x=%d y=%d exp=%d\n",
1664
i, g->region_size[i] - j, x, y, exponents[s_index]);
1667
x += get_bitsz(&s->gb, linbits);
1668
v = l3_unscale(x, exponents[s_index]);
1669
if (get_bits1(&s->gb))
1674
g->sb_hybrid[s_index++] = v;
1677
y += get_bitsz(&s->gb, linbits);
1678
v = l3_unscale(y, exponents[s_index]);
1679
if (get_bits1(&s->gb))
1684
g->sb_hybrid[s_index++] = v;
1688
/* high frequencies */
1689
vlc = &huff_quad_vlc[g->count1table_select];
1690
last_gb.buffer = NULL;
1691
while (s_index <= 572) {
1692
pos = get_bits_count(&s->gb);
1693
if (pos >= end_pos) {
1694
if (pos > end_pos && last_gb.buffer != NULL) {
1695
/* some encoders generate an incorrect size for this
1696
part. We must go back into the data */
1704
code = get_vlc2(&s->gb, vlc->table, vlc->bits, 2);
1705
dprintf("t=%d code=%d\n", g->count1table_select, code);
1709
if (code & (8 >> i)) {
1710
/* non zero value. Could use a hand coded function for
1712
v = l3_unscale(1, exponents[s_index]);
1713
if(get_bits1(&s->gb))
1718
g->sb_hybrid[s_index++] = v;
1721
while (s_index < 576)
1722
g->sb_hybrid[s_index++] = 0;
1726
/* Reorder short blocks from bitstream order to interleaved order. It
1727
would be faster to do it in parsing, but the code would be far more
1729
static void reorder_block(MPADecodeContext *s, GranuleDef *g)
1732
int32_t *ptr, *dst, *ptr1;
1735
if (g->block_type != 2)
1738
if (g->switch_point) {
1739
if (s->sample_rate_index != 8) {
1740
ptr = g->sb_hybrid + 36;
1742
ptr = g->sb_hybrid + 48;
1748
for(i=g->short_start;i<13;i++) {
1749
len = band_size_short[s->sample_rate_index][i];
1753
for(j=len;j>0;j--) {
1758
memcpy(ptr1, tmp, len * 3 * sizeof(int32_t));
1762
#define ISQRT2 FIXR(0.70710678118654752440)
1764
static void compute_stereo(MPADecodeContext *s,
1765
GranuleDef *g0, GranuleDef *g1)
1769
int sf_max, tmp0, tmp1, sf, len, non_zero_found;
1770
int32_t (*is_tab)[16];
1771
int32_t *tab0, *tab1;
1772
int non_zero_found_short[3];
1774
/* intensity stereo */
1775
if (s->mode_ext & MODE_EXT_I_STEREO) {
1780
is_tab = is_table_lsf[g1->scalefac_compress & 1];
1784
tab0 = g0->sb_hybrid + 576;
1785
tab1 = g1->sb_hybrid + 576;
1787
non_zero_found_short[0] = 0;
1788
non_zero_found_short[1] = 0;
1789
non_zero_found_short[2] = 0;
1790
k = (13 - g1->short_start) * 3 + g1->long_end - 3;
1791
for(i = 12;i >= g1->short_start;i--) {
1792
/* for last band, use previous scale factor */
1795
len = band_size_short[s->sample_rate_index][i];
1799
if (!non_zero_found_short[l]) {
1800
/* test if non zero band. if so, stop doing i-stereo */
1801
for(j=0;j<len;j++) {
1803
non_zero_found_short[l] = 1;
1807
sf = g1->scale_factors[k + l];
1813
for(j=0;j<len;j++) {
1815
tab0[j] = MULL(tmp0, v1);
1816
tab1[j] = MULL(tmp0, v2);
1820
if (s->mode_ext & MODE_EXT_MS_STEREO) {
1821
/* lower part of the spectrum : do ms stereo
1823
for(j=0;j<len;j++) {
1826
tab0[j] = MULL(tmp0 + tmp1, ISQRT2);
1827
tab1[j] = MULL(tmp0 - tmp1, ISQRT2);
1834
non_zero_found = non_zero_found_short[0] |
1835
non_zero_found_short[1] |
1836
non_zero_found_short[2];
1838
for(i = g1->long_end - 1;i >= 0;i--) {
1839
len = band_size_long[s->sample_rate_index][i];
1842
/* test if non zero band. if so, stop doing i-stereo */
1843
if (!non_zero_found) {
1844
for(j=0;j<len;j++) {
1850
/* for last band, use previous scale factor */
1851
k = (i == 21) ? 20 : i;
1852
sf = g1->scale_factors[k];
1857
for(j=0;j<len;j++) {
1859
tab0[j] = MULL(tmp0, v1);
1860
tab1[j] = MULL(tmp0, v2);
1864
if (s->mode_ext & MODE_EXT_MS_STEREO) {
1865
/* lower part of the spectrum : do ms stereo
1867
for(j=0;j<len;j++) {
1870
tab0[j] = MULL(tmp0 + tmp1, ISQRT2);
1871
tab1[j] = MULL(tmp0 - tmp1, ISQRT2);
1876
} else if (s->mode_ext & MODE_EXT_MS_STEREO) {
1877
/* ms stereo ONLY */
1878
/* NOTE: the 1/sqrt(2) normalization factor is included in the
1880
tab0 = g0->sb_hybrid;
1881
tab1 = g1->sb_hybrid;
1882
for(i=0;i<576;i++) {
1885
tab0[i] = tmp0 + tmp1;
1886
tab1[i] = tmp0 - tmp1;
1891
static void compute_antialias_integer(MPADecodeContext *s,
1897
/* we antialias only "long" bands */
1898
if (g->block_type == 2) {
1899
if (!g->switch_point)
1901
/* XXX: check this for 8000Hz case */
1907
ptr = g->sb_hybrid + 18;
1908
for(i = n;i > 0;i--) {
1909
int tmp0, tmp1, tmp2;
1910
csa = &csa_table[0][0];
1914
tmp2= MULH(tmp0 + tmp1, csa[0+4*j]);\
1915
ptr[-1-j] = 4*(tmp2 - MULH(tmp1, csa[2+4*j]));\
1916
ptr[ j] = 4*(tmp2 + MULH(tmp0, csa[3+4*j]));
1931
static void compute_antialias_float(MPADecodeContext *s,
1937
/* we antialias only "long" bands */
1938
if (g->block_type == 2) {
1939
if (!g->switch_point)
1941
/* XXX: check this for 8000Hz case */
1947
ptr = g->sb_hybrid + 18;
1948
for(i = n;i > 0;i--) {
1950
float *csa = &csa_table_float[0][0];
1951
#define FLOAT_AA(j)\
1954
ptr[-1-j] = lrintf(tmp0 * csa[0+4*j] - tmp1 * csa[1+4*j]);\
1955
ptr[ j] = lrintf(tmp0 * csa[1+4*j] + tmp1 * csa[0+4*j]);
1970
static void compute_imdct(MPADecodeContext *s,
1972
int32_t *sb_samples,
1975
int32_t *ptr, *win, *win1, *buf, *out_ptr, *ptr1;
1977
int i, j, mdct_long_end, v, sblimit;
1979
/* find last non zero block */
1980
ptr = g->sb_hybrid + 576;
1981
ptr1 = g->sb_hybrid + 2 * 18;
1982
while (ptr >= ptr1) {
1984
v = ptr[0] | ptr[1] | ptr[2] | ptr[3] | ptr[4] | ptr[5];
1988
sblimit = ((ptr - g->sb_hybrid) / 18) + 1;
1990
if (g->block_type == 2) {
1991
/* XXX: check for 8000 Hz */
1992
if (g->switch_point)
1997
mdct_long_end = sblimit;
2002
for(j=0;j<mdct_long_end;j++) {
2003
/* apply window & overlap with previous buffer */
2004
out_ptr = sb_samples + j;
2006
if (g->switch_point && j < 2)
2009
win1 = mdct_win[g->block_type];
2010
/* select frequency inversion */
2011
win = win1 + ((4 * 36) & -(j & 1));
2012
imdct36(out_ptr, buf, ptr, win);
2013
out_ptr += 18*SBLIMIT;
2017
for(j=mdct_long_end;j<sblimit;j++) {
2018
/* select frequency inversion */
2019
win = mdct_win[2] + ((4 * 36) & -(j & 1));
2020
out_ptr = sb_samples + j;
2026
imdct12(out2, ptr + 0);
2028
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*1];
2029
buf[i + 6*2] = MULH(out2[i + 6], win[i + 6]);
2032
imdct12(out2, ptr + 1);
2034
*out_ptr = MULH(out2[i], win[i]) + buf[i + 6*2];
2035
buf[i + 6*0] = MULH(out2[i + 6], win[i + 6]);
2038
imdct12(out2, ptr + 2);
2040
buf[i + 6*0] = MULH(out2[i], win[i]) + buf[i + 6*0];
2041
buf[i + 6*1] = MULH(out2[i + 6], win[i + 6]);
2048
for(j=sblimit;j<SBLIMIT;j++) {
2050
out_ptr = sb_samples + j;
2061
void sample_dump(int fnum, int32_t *tab, int n)
2063
static FILE *files[16], *f;
2070
snprintf(buf, sizeof(buf), "/tmp/out%d.%s.pcm",
2072
#ifdef USE_HIGHPRECISION
2078
f = fopen(buf, "w");
2086
av_log(NULL, AV_LOG_DEBUG, "pos=%d\n", pos);
2088
av_log(NULL, AV_LOG_DEBUG, " %0.4f", (double)tab[i] / FRAC_ONE);
2090
av_log(NULL, AV_LOG_DEBUG, "\n");
2095
/* normalize to 23 frac bits */
2096
v = tab[i] << (23 - FRAC_BITS);
2097
fwrite(&v, 1, sizeof(int32_t), f);
2103
/* main layer3 decoding function */
2104
static int mp_decode_layer3(MPADecodeContext *s)
2106
int nb_granules, main_data_begin, private_bits;
2107
int gr, ch, blocksplit_flag, i, j, k, n, bits_pos, bits_left;
2108
GranuleDef granules[2][2], *g;
2109
int16_t exponents[576];
2111
/* read side info */
2113
main_data_begin = get_bits(&s->gb, 8);
2114
if (s->nb_channels == 2)
2115
private_bits = get_bits(&s->gb, 2);
2117
private_bits = get_bits(&s->gb, 1);
2120
main_data_begin = get_bits(&s->gb, 9);
2121
if (s->nb_channels == 2)
2122
private_bits = get_bits(&s->gb, 3);
2124
private_bits = get_bits(&s->gb, 5);
2126
for(ch=0;ch<s->nb_channels;ch++) {
2127
granules[ch][0].scfsi = 0; /* all scale factors are transmitted */
2128
granules[ch][1].scfsi = get_bits(&s->gb, 4);
2132
for(gr=0;gr<nb_granules;gr++) {
2133
for(ch=0;ch<s->nb_channels;ch++) {
2134
dprintf("gr=%d ch=%d: side_info\n", gr, ch);
2135
g = &granules[ch][gr];
2136
g->part2_3_length = get_bits(&s->gb, 12);
2137
g->big_values = get_bits(&s->gb, 9);
2138
g->global_gain = get_bits(&s->gb, 8);
2139
/* if MS stereo only is selected, we precompute the
2140
1/sqrt(2) renormalization factor */
2141
if ((s->mode_ext & (MODE_EXT_MS_STEREO | MODE_EXT_I_STEREO)) ==
2143
g->global_gain -= 2;
2145
g->scalefac_compress = get_bits(&s->gb, 9);
2147
g->scalefac_compress = get_bits(&s->gb, 4);
2148
blocksplit_flag = get_bits(&s->gb, 1);
2149
if (blocksplit_flag) {
2150
g->block_type = get_bits(&s->gb, 2);
2151
if (g->block_type == 0)
2153
g->switch_point = get_bits(&s->gb, 1);
2155
g->table_select[i] = get_bits(&s->gb, 5);
2157
g->subblock_gain[i] = get_bits(&s->gb, 3);
2158
/* compute huffman coded region sizes */
2159
if (g->block_type == 2)
2160
g->region_size[0] = (36 / 2);
2162
if (s->sample_rate_index <= 2)
2163
g->region_size[0] = (36 / 2);
2164
else if (s->sample_rate_index != 8)
2165
g->region_size[0] = (54 / 2);
2167
g->region_size[0] = (108 / 2);
2169
g->region_size[1] = (576 / 2);
2171
int region_address1, region_address2, l;
2173
g->switch_point = 0;
2175
g->table_select[i] = get_bits(&s->gb, 5);
2176
/* compute huffman coded region sizes */
2177
region_address1 = get_bits(&s->gb, 4);
2178
region_address2 = get_bits(&s->gb, 3);
2179
dprintf("region1=%d region2=%d\n",
2180
region_address1, region_address2);
2182
band_index_long[s->sample_rate_index][region_address1 + 1] >> 1;
2183
l = region_address1 + region_address2 + 2;
2184
/* should not overflow */
2188
band_index_long[s->sample_rate_index][l] >> 1;
2190
/* convert region offsets to region sizes and truncate
2191
size to big_values */
2192
g->region_size[2] = (576 / 2);
2195
k = g->region_size[i];
2196
if (k > g->big_values)
2198
g->region_size[i] = k - j;
2202
/* compute band indexes */
2203
if (g->block_type == 2) {
2204
if (g->switch_point) {
2205
/* if switched mode, we handle the 36 first samples as
2206
long blocks. For 8000Hz, we handle the 48 first
2207
exponents as long blocks (XXX: check this!) */
2208
if (s->sample_rate_index <= 2)
2210
else if (s->sample_rate_index != 8)
2213
g->long_end = 4; /* 8000 Hz */
2215
if (s->sample_rate_index != 8)
2224
g->short_start = 13;
2230
g->preflag = get_bits(&s->gb, 1);
2231
g->scalefac_scale = get_bits(&s->gb, 1);
2232
g->count1table_select = get_bits(&s->gb, 1);
2233
dprintf("block_type=%d switch_point=%d\n",
2234
g->block_type, g->switch_point);
2239
/* now we get bits from the main_data_begin offset */
2240
dprintf("seekback: %d\n", main_data_begin);
2241
seek_to_maindata(s, main_data_begin);
2244
for(gr=0;gr<nb_granules;gr++) {
2245
for(ch=0;ch<s->nb_channels;ch++) {
2246
g = &granules[ch][gr];
2248
bits_pos = get_bits_count(&s->gb);
2252
int slen, slen1, slen2;
2254
/* MPEG1 scale factors */
2255
slen1 = slen_table[0][g->scalefac_compress];
2256
slen2 = slen_table[1][g->scalefac_compress];
2257
dprintf("slen1=%d slen2=%d\n", slen1, slen2);
2258
if (g->block_type == 2) {
2259
n = g->switch_point ? 17 : 18;
2262
g->scale_factors[j++] = get_bitsz(&s->gb, slen1);
2264
g->scale_factors[j++] = get_bitsz(&s->gb, slen2);
2266
g->scale_factors[j++] = 0;
2268
sc = granules[ch][0].scale_factors;
2271
n = (k == 0 ? 6 : 5);
2272
if ((g->scfsi & (0x8 >> k)) == 0) {
2273
slen = (k < 2) ? slen1 : slen2;
2275
g->scale_factors[j++] = get_bitsz(&s->gb, slen);
2277
/* simply copy from last granule */
2279
g->scale_factors[j] = sc[j];
2284
g->scale_factors[j++] = 0;
2288
dprintf("scfsi=%x gr=%d ch=%d scale_factors:\n",
2291
dprintf(" %d", g->scale_factors[i]);
2296
int tindex, tindex2, slen[4], sl, sf;
2298
/* LSF scale factors */
2299
if (g->block_type == 2) {
2300
tindex = g->switch_point ? 2 : 1;
2304
sf = g->scalefac_compress;
2305
if ((s->mode_ext & MODE_EXT_I_STEREO) && ch == 1) {
2306
/* intensity stereo case */
2309
lsf_sf_expand(slen, sf, 6, 6, 0);
2311
} else if (sf < 244) {
2312
lsf_sf_expand(slen, sf - 180, 4, 4, 0);
2315
lsf_sf_expand(slen, sf - 244, 3, 0, 0);
2321
lsf_sf_expand(slen, sf, 5, 4, 4);
2323
} else if (sf < 500) {
2324
lsf_sf_expand(slen, sf - 400, 5, 4, 0);
2327
lsf_sf_expand(slen, sf - 500, 3, 0, 0);
2335
n = lsf_nsf_table[tindex2][tindex][k];
2338
g->scale_factors[j++] = get_bitsz(&s->gb, sl);
2340
/* XXX: should compute exact size */
2342
g->scale_factors[j] = 0;
2345
dprintf("gr=%d ch=%d scale_factors:\n",
2348
dprintf(" %d", g->scale_factors[i]);
2354
exponents_from_scale_factors(s, g, exponents);
2356
/* read Huffman coded residue */
2357
if (huffman_decode(s, g, exponents,
2358
bits_pos + g->part2_3_length) < 0)
2361
sample_dump(0, g->sb_hybrid, 576);
2364
/* skip extension bits */
2365
bits_left = g->part2_3_length - (get_bits_count(&s->gb) - bits_pos);
2366
if (bits_left < 0) {
2367
dprintf("bits_left=%d\n", bits_left);
2370
while (bits_left >= 16) {
2371
skip_bits(&s->gb, 16);
2375
skip_bits(&s->gb, bits_left);
2378
if (s->nb_channels == 2)
2379
compute_stereo(s, &granules[0][gr], &granules[1][gr]);
2381
for(ch=0;ch<s->nb_channels;ch++) {
2382
g = &granules[ch][gr];
2384
reorder_block(s, g);
2386
sample_dump(0, g->sb_hybrid, 576);
2388
s->compute_antialias(s, g);
2390
sample_dump(1, g->sb_hybrid, 576);
2392
compute_imdct(s, g, &s->sb_samples[ch][18 * gr][0], s->mdct_buf[ch]);
2394
sample_dump(2, &s->sb_samples[ch][18 * gr][0], 576);
2398
return nb_granules * 18;
2401
static int mp_decode_frame(MPADecodeContext *s,
2404
int i, nb_frames, ch;
2405
OUT_INT *samples_ptr;
2407
init_get_bits(&s->gb, s->inbuf + HEADER_SIZE,
2408
(s->inbuf_ptr - s->inbuf - HEADER_SIZE)*8);
2410
/* skip error protection field */
2411
if (s->error_protection)
2412
get_bits(&s->gb, 16);
2414
dprintf("frame %d:\n", s->frame_count);
2417
nb_frames = mp_decode_layer1(s);
2420
nb_frames = mp_decode_layer2(s);
2424
nb_frames = mp_decode_layer3(s);
2428
for(i=0;i<nb_frames;i++) {
2429
for(ch=0;ch<s->nb_channels;ch++) {
2431
dprintf("%d-%d:", i, ch);
2432
for(j=0;j<SBLIMIT;j++)
2433
dprintf(" %0.6f", (double)s->sb_samples[ch][i][j] / FRAC_ONE);
2438
/* apply the synthesis filter */
2439
for(ch=0;ch<s->nb_channels;ch++) {
2440
samples_ptr = samples + ch;
2441
for(i=0;i<nb_frames;i++) {
2442
ff_mpa_synth_filter(s->synth_buf[ch], &(s->synth_buf_offset[ch]),
2443
window, &s->dither_state,
2444
samples_ptr, s->nb_channels,
2445
s->sb_samples[ch][i]);
2446
samples_ptr += 32 * s->nb_channels;
2452
return nb_frames * 32 * sizeof(OUT_INT) * s->nb_channels;
2455
static int decode_frame(AVCodecContext * avctx,
2456
void *data, int *data_size,
2457
uint8_t * buf, int buf_size)
2459
MPADecodeContext *s = avctx->priv_data;
2463
OUT_INT *out_samples = data;
2466
while (buf_size > 0) {
2467
len = s->inbuf_ptr - s->inbuf;
2468
if (s->frame_size == 0) {
2469
/* special case for next header for first frame in free
2470
format case (XXX: find a simpler method) */
2471
if (s->free_format_next_header != 0) {
2472
s->inbuf[0] = s->free_format_next_header >> 24;
2473
s->inbuf[1] = s->free_format_next_header >> 16;
2474
s->inbuf[2] = s->free_format_next_header >> 8;
2475
s->inbuf[3] = s->free_format_next_header;
2476
s->inbuf_ptr = s->inbuf + 4;
2477
s->free_format_next_header = 0;
2480
/* no header seen : find one. We need at least HEADER_SIZE
2481
bytes to parse it */
2482
len = HEADER_SIZE - len;
2486
memcpy(s->inbuf_ptr, buf_ptr, len);
2489
s->inbuf_ptr += len;
2491
if ((s->inbuf_ptr - s->inbuf) >= HEADER_SIZE) {
2493
header = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
2494
(s->inbuf[2] << 8) | s->inbuf[3];
2496
if (ff_mpa_check_header(header) < 0) {
2497
/* no sync found : move by one byte (inefficient, but simple!) */
2498
memmove(s->inbuf, s->inbuf + 1, s->inbuf_ptr - s->inbuf - 1);
2500
dprintf("skip %x\n", header);
2501
/* reset free format frame size to give a chance
2502
to get a new bitrate */
2503
s->free_format_frame_size = 0;
2505
if (decode_header(s, header) == 1) {
2506
/* free format: prepare to compute frame size */
2509
/* update codec info */
2510
avctx->sample_rate = s->sample_rate;
2511
avctx->channels = s->nb_channels;
2512
avctx->bit_rate = s->bit_rate;
2513
avctx->sub_id = s->layer;
2516
avctx->frame_size = 384;
2519
avctx->frame_size = 1152;
2523
avctx->frame_size = 576;
2525
avctx->frame_size = 1152;
2530
} else if (s->frame_size == -1) {
2531
/* free format : find next sync to compute frame size */
2532
len = MPA_MAX_CODED_FRAME_SIZE - len;
2536
/* frame too long: resync */
2538
memmove(s->inbuf, s->inbuf + 1, s->inbuf_ptr - s->inbuf - 1);
2545
memcpy(s->inbuf_ptr, buf_ptr, len);
2546
/* check for header */
2547
p = s->inbuf_ptr - 3;
2548
pend = s->inbuf_ptr + len - 4;
2550
header = (p[0] << 24) | (p[1] << 16) |
2552
header1 = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
2553
(s->inbuf[2] << 8) | s->inbuf[3];
2554
/* check with high probability that we have a
2556
if ((header & SAME_HEADER_MASK) ==
2557
(header1 & SAME_HEADER_MASK)) {
2558
/* header found: update pointers */
2559
len = (p + 4) - s->inbuf_ptr;
2563
/* compute frame size */
2564
s->free_format_next_header = header;
2565
s->free_format_frame_size = s->inbuf_ptr - s->inbuf;
2566
padding = (header1 >> 9) & 1;
2568
s->free_format_frame_size -= padding * 4;
2570
s->free_format_frame_size -= padding;
2571
dprintf("free frame size=%d padding=%d\n",
2572
s->free_format_frame_size, padding);
2573
decode_header(s, header1);
2578
/* not found: simply increase pointers */
2580
s->inbuf_ptr += len;
2583
} else if (len < s->frame_size) {
2584
if (s->frame_size > MPA_MAX_CODED_FRAME_SIZE)
2585
s->frame_size = MPA_MAX_CODED_FRAME_SIZE;
2586
len = s->frame_size - len;
2589
memcpy(s->inbuf_ptr, buf_ptr, len);
2591
s->inbuf_ptr += len;
2595
if (s->frame_size > 0 &&
2596
(s->inbuf_ptr - s->inbuf) >= s->frame_size) {
2597
if (avctx->parse_only) {
2598
/* simply return the frame data */
2599
*(uint8_t **)data = s->inbuf;
2600
out_size = s->inbuf_ptr - s->inbuf;
2602
out_size = mp_decode_frame(s, out_samples);
2604
s->inbuf_ptr = s->inbuf;
2607
*data_size = out_size;
2609
av_log(avctx, AV_LOG_DEBUG, "Error while decoding mpeg audio frame\n"); //FIXME return -1 / but also return the number of bytes consumed
2613
return buf_ptr - buf;
2617
static int decode_frame_adu(AVCodecContext * avctx,
2618
void *data, int *data_size,
2619
uint8_t * buf, int buf_size)
2621
MPADecodeContext *s = avctx->priv_data;
2624
OUT_INT *out_samples = data;
2628
// Discard too short frames
2629
if (buf_size < HEADER_SIZE) {
2635
if (len > MPA_MAX_CODED_FRAME_SIZE)
2636
len = MPA_MAX_CODED_FRAME_SIZE;
2638
memcpy(s->inbuf, buf, len);
2639
s->inbuf_ptr = s->inbuf + len;
2641
// Get header and restore sync word
2642
header = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
2643
(s->inbuf[2] << 8) | s->inbuf[3] | 0xffe00000;
2645
if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame
2650
decode_header(s, header);
2651
/* update codec info */
2652
avctx->sample_rate = s->sample_rate;
2653
avctx->channels = s->nb_channels;
2654
avctx->bit_rate = s->bit_rate;
2655
avctx->sub_id = s->layer;
2657
avctx->frame_size=s->frame_size = len;
2659
if (avctx->parse_only) {
2660
/* simply return the frame data */
2661
*(uint8_t **)data = s->inbuf;
2662
out_size = s->inbuf_ptr - s->inbuf;
2664
out_size = mp_decode_frame(s, out_samples);
2667
*data_size = out_size;
2672
/* Next 3 arrays are indexed by channel config number (passed via codecdata) */
2673
static int mp3Frames[16] = {0,1,1,2,3,3,4,5,2}; /* number of mp3 decoder instances */
2674
static int mp3Channels[16] = {0,1,2,3,4,5,6,8,4}; /* total output channels */
2675
/* offsets into output buffer, assume output order is FL FR BL BR C LFE */
2676
static int chan_offset[9][5] = {
2681
{2,0,3}, // C FLR BS
2682
{4,0,2}, // C FLR BLRS
2683
{4,0,2,5}, // C FLR BLRS LFE
2684
{4,0,2,6,5}, // C FLR BLRS BLR LFE
2689
static int decode_init_mp3on4(AVCodecContext * avctx)
2691
MP3On4DecodeContext *s = avctx->priv_data;
2694
if ((avctx->extradata_size < 2) || (avctx->extradata == NULL)) {
2695
av_log(avctx, AV_LOG_ERROR, "Codec extradata missing or too short.\n");
2699
s->chan_cfg = (((unsigned char *)avctx->extradata)[1] >> 3) & 0x0f;
2700
s->frames = mp3Frames[s->chan_cfg];
2702
av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");
2705
avctx->channels = mp3Channels[s->chan_cfg];
2707
/* Init the first mp3 decoder in standard way, so that all tables get builded
2708
* We replace avctx->priv_data with the context of the first decoder so that
2709
* decode_init() does not have to be changed.
2710
* Other decoders will be inited here copying data from the first context
2712
// Allocate zeroed memory for the first decoder context
2713
s->mp3decctx[0] = av_mallocz(sizeof(MPADecodeContext));
2714
// Put decoder context in place to make init_decode() happy
2715
avctx->priv_data = s->mp3decctx[0];
2717
// Restore mp3on4 context pointer
2718
avctx->priv_data = s;
2719
s->mp3decctx[0]->adu_mode = 1; // Set adu mode
2721
/* Create a separate codec/context for each frame (first is already ok).
2722
* Each frame is 1 or 2 channels - up to 5 frames allowed
2724
for (i = 1; i < s->frames; i++) {
2725
s->mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));
2726
s->mp3decctx[i]->compute_antialias = s->mp3decctx[0]->compute_antialias;
2727
s->mp3decctx[i]->inbuf = &s->mp3decctx[i]->inbuf1[0][BACKSTEP_SIZE];
2728
s->mp3decctx[i]->inbuf_ptr = s->mp3decctx[i]->inbuf;
2729
s->mp3decctx[i]->adu_mode = 1;
2736
static int decode_close_mp3on4(AVCodecContext * avctx)
2738
MP3On4DecodeContext *s = avctx->priv_data;
2741
for (i = 0; i < s->frames; i++)
2742
if (s->mp3decctx[i])
2743
av_free(s->mp3decctx[i]);
2749
static int decode_frame_mp3on4(AVCodecContext * avctx,
2750
void *data, int *data_size,
2751
uint8_t * buf, int buf_size)
2753
MP3On4DecodeContext *s = avctx->priv_data;
2754
MPADecodeContext *m;
2755
int len, out_size = 0;
2757
OUT_INT *out_samples = data;
2758
OUT_INT decoded_buf[MPA_FRAME_SIZE * MPA_MAX_CHANNELS];
2759
OUT_INT *outptr, *bp;
2761
unsigned char *start2 = buf, *start;
2763
int off = avctx->channels;
2764
int *coff = chan_offset[s->chan_cfg];
2768
// Discard too short frames
2769
if (buf_size < HEADER_SIZE) {
2774
// If only one decoder interleave is not needed
2775
outptr = s->frames == 1 ? out_samples : decoded_buf;
2777
for (fr = 0; fr < s->frames; fr++) {
2779
fsize = (start[0] << 4) | (start[1] >> 4);
2784
if (fsize > MPA_MAX_CODED_FRAME_SIZE)
2785
fsize = MPA_MAX_CODED_FRAME_SIZE;
2786
m = s->mp3decctx[fr];
2788
/* copy original to new */
2789
m->inbuf_ptr = m->inbuf + fsize;
2790
memcpy(m->inbuf, start, fsize);
2793
header = (m->inbuf[0] << 24) | (m->inbuf[1] << 16) |
2794
(m->inbuf[2] << 8) | m->inbuf[3] | 0xfff00000;
2796
if (ff_mpa_check_header(header) < 0) { // Bad header, discard block
2801
decode_header(m, header);
2802
mp_decode_frame(m, decoded_buf);
2804
n = MPA_FRAME_SIZE * m->nb_channels;
2805
out_size += n * sizeof(OUT_INT);
2807
/* interleave output data */
2808
bp = out_samples + coff[fr];
2809
if(m->nb_channels == 1) {
2810
for(j = 0; j < n; j++) {
2811
*bp = decoded_buf[j];
2815
for(j = 0; j < n; j++) {
2816
bp[0] = decoded_buf[j++];
2817
bp[1] = decoded_buf[j];
2824
/* update codec info */
2825
avctx->sample_rate = s->mp3decctx[0]->sample_rate;
2826
avctx->frame_size= buf_size;
2827
avctx->bit_rate = 0;
2828
for (i = 0; i < s->frames; i++)
2829
avctx->bit_rate += s->mp3decctx[i]->bit_rate;
2831
*data_size = out_size;
2836
AVCodec mp2_decoder =
2841
sizeof(MPADecodeContext),
2846
CODEC_CAP_PARSE_ONLY,
2849
AVCodec mp3_decoder =
2854
sizeof(MPADecodeContext),
2859
CODEC_CAP_PARSE_ONLY,
2862
AVCodec mp3adu_decoder =
2867
sizeof(MPADecodeContext),
2872
CODEC_CAP_PARSE_ONLY,
2875
AVCodec mp3on4_decoder =
2880
sizeof(MP3On4DecodeContext),
2883
decode_close_mp3on4,
2884
decode_frame_mp3on4,