mpegaudiodec.c
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1 /*
2  * MPEG Audio decoder
3  * Copyright (c) 2001, 2002 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 #include "libavutil/audioconvert.h"
28 #include "avcodec.h"
29 #include "internal.h"
30 #include "get_bits.h"
31 #include "mathops.h"
32 #include "mpegaudiodsp.h"
33 
34 /*
35  * TODO:
36  * - test lsf / mpeg25 extensively.
37  */
38 
39 #include "mpegaudio.h"
40 #include "mpegaudiodecheader.h"
41 
42 #define BACKSTEP_SIZE 512
43 #define EXTRABYTES 24
44 #define LAST_BUF_SIZE 2 * BACKSTEP_SIZE + EXTRABYTES
45 
46 /* layer 3 "granule" */
47 typedef struct GranuleDef {
48  uint8_t scfsi;
53  uint8_t block_type;
54  uint8_t switch_point;
55  int table_select[3];
56  int subblock_gain[3];
57  uint8_t scalefac_scale;
59  int region_size[3]; /* number of huffman codes in each region */
60  int preflag;
61  int short_start, long_end; /* long/short band indexes */
62  uint8_t scale_factors[40];
63  DECLARE_ALIGNED(16, INTFLOAT, sb_hybrid)[SBLIMIT * 18]; /* 576 samples */
64 } GranuleDef;
65 
66 typedef struct MPADecodeContext {
70  /* next header (used in free format parsing) */
77  INTFLOAT mdct_buf[MPA_MAX_CHANNELS][SBLIMIT * 18]; /* previous samples, for layer 3 MDCT */
78  GranuleDef granules[2][2]; /* Used in Layer 3 */
79  int adu_mode;
86 
87 #if CONFIG_FLOAT
88 # define SHR(a,b) ((a)*(1.0f/(1<<(b))))
89 # define FIXR_OLD(a) ((int)((a) * FRAC_ONE + 0.5))
90 # define FIXR(x) ((float)(x))
91 # define FIXHR(x) ((float)(x))
92 # define MULH3(x, y, s) ((s)*(y)*(x))
93 # define MULLx(x, y, s) ((y)*(x))
94 # define RENAME(a) a ## _float
95 # define OUT_FMT AV_SAMPLE_FMT_FLT
96 #else
97 # define SHR(a,b) ((a)>>(b))
98 /* WARNING: only correct for positive numbers */
99 # define FIXR_OLD(a) ((int)((a) * FRAC_ONE + 0.5))
100 # define FIXR(a) ((int)((a) * FRAC_ONE + 0.5))
101 # define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5))
102 # define MULH3(x, y, s) MULH((s)*(x), y)
103 # define MULLx(x, y, s) MULL(x,y,s)
104 # define RENAME(a) a ## _fixed
105 # define OUT_FMT AV_SAMPLE_FMT_S16
106 #endif
107 
108 /****************/
109 
110 #define HEADER_SIZE 4
111 
112 #include "mpegaudiodata.h"
113 #include "mpegaudiodectab.h"
114 
115 /* vlc structure for decoding layer 3 huffman tables */
116 static VLC huff_vlc[16];
118  0 + 128 + 128 + 128 + 130 + 128 + 154 + 166 +
119  142 + 204 + 190 + 170 + 542 + 460 + 662 + 414
120  ][2];
121 static const int huff_vlc_tables_sizes[16] = {
122  0, 128, 128, 128, 130, 128, 154, 166,
123  142, 204, 190, 170, 542, 460, 662, 414
124 };
125 static VLC huff_quad_vlc[2];
126 static VLC_TYPE huff_quad_vlc_tables[128+16][2];
127 static const int huff_quad_vlc_tables_sizes[2] = { 128, 16 };
128 /* computed from band_size_long */
129 static uint16_t band_index_long[9][23];
130 #include "mpegaudio_tablegen.h"
131 /* intensity stereo coef table */
132 static INTFLOAT is_table[2][16];
133 static INTFLOAT is_table_lsf[2][2][16];
134 static INTFLOAT csa_table[8][4];
135 
136 static int16_t division_tab3[1<<6 ];
137 static int16_t division_tab5[1<<8 ];
138 static int16_t division_tab9[1<<11];
139 
140 static int16_t * const division_tabs[4] = {
142 };
143 
144 /* lower 2 bits: modulo 3, higher bits: shift */
145 static uint16_t scale_factor_modshift[64];
146 /* [i][j]: 2^(-j/3) * FRAC_ONE * 2^(i+2) / (2^(i+2) - 1) */
147 static int32_t scale_factor_mult[15][3];
148 /* mult table for layer 2 group quantization */
149 
150 #define SCALE_GEN(v) \
151 { FIXR_OLD(1.0 * (v)), FIXR_OLD(0.7937005259 * (v)), FIXR_OLD(0.6299605249 * (v)) }
152 
153 static const int32_t scale_factor_mult2[3][3] = {
154  SCALE_GEN(4.0 / 3.0), /* 3 steps */
155  SCALE_GEN(4.0 / 5.0), /* 5 steps */
156  SCALE_GEN(4.0 / 9.0), /* 9 steps */
157 };
158 
164 {
165  int i, k, j = 0;
166  g->region_size[2] = 576 / 2;
167  for (i = 0; i < 3; i++) {
168  k = FFMIN(g->region_size[i], g->big_values);
169  g->region_size[i] = k - j;
170  j = k;
171  }
172 }
173 
175 {
176  if (g->block_type == 2)
177  g->region_size[0] = (36 / 2);
178  else {
179  if (s->sample_rate_index <= 2)
180  g->region_size[0] = (36 / 2);
181  else if (s->sample_rate_index != 8)
182  g->region_size[0] = (54 / 2);
183  else
184  g->region_size[0] = (108 / 2);
185  }
186  g->region_size[1] = (576 / 2);
187 }
188 
189 static void ff_init_long_region(MPADecodeContext *s, GranuleDef *g, int ra1, int ra2)
190 {
191  int l;
192  g->region_size[0] = band_index_long[s->sample_rate_index][ra1 + 1] >> 1;
193  /* should not overflow */
194  l = FFMIN(ra1 + ra2 + 2, 22);
195  g->region_size[1] = band_index_long[s->sample_rate_index][ l] >> 1;
196 }
197 
199 {
200  if (g->block_type == 2) {
201  if (g->switch_point) {
202  /* if switched mode, we handle the 36 first samples as
203  long blocks. For 8000Hz, we handle the 48 first
204  exponents as long blocks (XXX: check this!) */
205  if (s->sample_rate_index <= 2)
206  g->long_end = 8;
207  else if (s->sample_rate_index != 8)
208  g->long_end = 6;
209  else
210  g->long_end = 4; /* 8000 Hz */
211 
212  g->short_start = 3;
213  } else {
214  g->long_end = 0;
215  g->short_start = 0;
216  }
217  } else {
218  g->short_start = 13;
219  g->long_end = 22;
220  }
221 }
222 
223 /* layer 1 unscaling */
224 /* n = number of bits of the mantissa minus 1 */
225 static inline int l1_unscale(int n, int mant, int scale_factor)
226 {
227  int shift, mod;
228  int64_t val;
229 
230  shift = scale_factor_modshift[scale_factor];
231  mod = shift & 3;
232  shift >>= 2;
233  val = MUL64(mant + (-1 << n) + 1, scale_factor_mult[n-1][mod]);
234  shift += n;
235  /* NOTE: at this point, 1 <= shift >= 21 + 15 */
236  return (int)((val + (1LL << (shift - 1))) >> shift);
237 }
238 
239 static inline int l2_unscale_group(int steps, int mant, int scale_factor)
240 {
241  int shift, mod, val;
242 
243  shift = scale_factor_modshift[scale_factor];
244  mod = shift & 3;
245  shift >>= 2;
246 
247  val = (mant - (steps >> 1)) * scale_factor_mult2[steps >> 2][mod];
248  /* NOTE: at this point, 0 <= shift <= 21 */
249  if (shift > 0)
250  val = (val + (1 << (shift - 1))) >> shift;
251  return val;
252 }
253 
254 /* compute value^(4/3) * 2^(exponent/4). It normalized to FRAC_BITS */
255 static inline int l3_unscale(int value, int exponent)
256 {
257  unsigned int m;
258  int e;
259 
260  e = table_4_3_exp [4 * value + (exponent & 3)];
261  m = table_4_3_value[4 * value + (exponent & 3)];
262  e -= exponent >> 2;
263  assert(e >= 1);
264  if (e > 31)
265  return 0;
266  m = (m + (1 << (e - 1))) >> e;
267 
268  return m;
269 }
270 
271 static av_cold void decode_init_static(void)
272 {
273  int i, j, k;
274  int offset;
275 
276  /* scale factors table for layer 1/2 */
277  for (i = 0; i < 64; i++) {
278  int shift, mod;
279  /* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */
280  shift = i / 3;
281  mod = i % 3;
282  scale_factor_modshift[i] = mod | (shift << 2);
283  }
284 
285  /* scale factor multiply for layer 1 */
286  for (i = 0; i < 15; i++) {
287  int n, norm;
288  n = i + 2;
289  norm = ((INT64_C(1) << n) * FRAC_ONE) / ((1 << n) - 1);
290  scale_factor_mult[i][0] = MULLx(norm, FIXR(1.0 * 2.0), FRAC_BITS);
291  scale_factor_mult[i][1] = MULLx(norm, FIXR(0.7937005259 * 2.0), FRAC_BITS);
292  scale_factor_mult[i][2] = MULLx(norm, FIXR(0.6299605249 * 2.0), FRAC_BITS);
293  av_dlog(NULL, "%d: norm=%x s=%x %x %x\n", i, norm,
294  scale_factor_mult[i][0],
295  scale_factor_mult[i][1],
296  scale_factor_mult[i][2]);
297  }
298 
299  RENAME(ff_mpa_synth_init)(RENAME(ff_mpa_synth_window));
300 
301  /* huffman decode tables */
302  offset = 0;
303  for (i = 1; i < 16; i++) {
304  const HuffTable *h = &mpa_huff_tables[i];
305  int xsize, x, y;
306  uint8_t tmp_bits [512];
307  uint16_t tmp_codes[512];
308 
309  memset(tmp_bits , 0, sizeof(tmp_bits ));
310  memset(tmp_codes, 0, sizeof(tmp_codes));
311 
312  xsize = h->xsize;
313 
314  j = 0;
315  for (x = 0; x < xsize; x++) {
316  for (y = 0; y < xsize; y++) {
317  tmp_bits [(x << 5) | y | ((x&&y)<<4)]= h->bits [j ];
318  tmp_codes[(x << 5) | y | ((x&&y)<<4)]= h->codes[j++];
319  }
320  }
321 
322  /* XXX: fail test */
323  huff_vlc[i].table = huff_vlc_tables+offset;
324  huff_vlc[i].table_allocated = huff_vlc_tables_sizes[i];
325  init_vlc(&huff_vlc[i], 7, 512,
326  tmp_bits, 1, 1, tmp_codes, 2, 2,
328  offset += huff_vlc_tables_sizes[i];
329  }
330  assert(offset == FF_ARRAY_ELEMS(huff_vlc_tables));
331 
332  offset = 0;
333  for (i = 0; i < 2; i++) {
334  huff_quad_vlc[i].table = huff_quad_vlc_tables+offset;
335  huff_quad_vlc[i].table_allocated = huff_quad_vlc_tables_sizes[i];
336  init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16,
337  mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1,
339  offset += huff_quad_vlc_tables_sizes[i];
340  }
341  assert(offset == FF_ARRAY_ELEMS(huff_quad_vlc_tables));
342 
343  for (i = 0; i < 9; i++) {
344  k = 0;
345  for (j = 0; j < 22; j++) {
346  band_index_long[i][j] = k;
347  k += band_size_long[i][j];
348  }
349  band_index_long[i][22] = k;
350  }
351 
352  /* compute n ^ (4/3) and store it in mantissa/exp format */
353 
355 
356  for (i = 0; i < 4; i++) {
357  if (ff_mpa_quant_bits[i] < 0) {
358  for (j = 0; j < (1 << (-ff_mpa_quant_bits[i]+1)); j++) {
359  int val1, val2, val3, steps;
360  int val = j;
361  steps = ff_mpa_quant_steps[i];
362  val1 = val % steps;
363  val /= steps;
364  val2 = val % steps;
365  val3 = val / steps;
366  division_tabs[i][j] = val1 + (val2 << 4) + (val3 << 8);
367  }
368  }
369  }
370 
371 
372  for (i = 0; i < 7; i++) {
373  float f;
374  INTFLOAT v;
375  if (i != 6) {
376  f = tan((double)i * M_PI / 12.0);
377  v = FIXR(f / (1.0 + f));
378  } else {
379  v = FIXR(1.0);
380  }
381  is_table[0][ i] = v;
382  is_table[1][6 - i] = v;
383  }
384  /* invalid values */
385  for (i = 7; i < 16; i++)
386  is_table[0][i] = is_table[1][i] = 0.0;
387 
388  for (i = 0; i < 16; i++) {
389  double f;
390  int e, k;
391 
392  for (j = 0; j < 2; j++) {
393  e = -(j + 1) * ((i + 1) >> 1);
394  f = pow(2.0, e / 4.0);
395  k = i & 1;
396  is_table_lsf[j][k ^ 1][i] = FIXR(f);
397  is_table_lsf[j][k ][i] = FIXR(1.0);
398  av_dlog(NULL, "is_table_lsf %d %d: %f %f\n",
399  i, j, (float) is_table_lsf[j][0][i],
400  (float) is_table_lsf[j][1][i]);
401  }
402  }
403 
404  for (i = 0; i < 8; i++) {
405  float ci, cs, ca;
406  ci = ci_table[i];
407  cs = 1.0 / sqrt(1.0 + ci * ci);
408  ca = cs * ci;
409 #if !CONFIG_FLOAT
410  csa_table[i][0] = FIXHR(cs/4);
411  csa_table[i][1] = FIXHR(ca/4);
412  csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4);
413  csa_table[i][3] = FIXHR(ca/4) - FIXHR(cs/4);
414 #else
415  csa_table[i][0] = cs;
416  csa_table[i][1] = ca;
417  csa_table[i][2] = ca + cs;
418  csa_table[i][3] = ca - cs;
419 #endif
420  }
421 }
422 
423 static av_cold int decode_init(AVCodecContext * avctx)
424 {
425  static int initialized_tables = 0;
426  MPADecodeContext *s = avctx->priv_data;
427 
428  if (!initialized_tables) {
430  initialized_tables = 1;
431  }
432 
433  s->avctx = avctx;
434 
435  ff_mpadsp_init(&s->mpadsp);
436 
437  avctx->sample_fmt= OUT_FMT;
438  s->err_recognition = avctx->err_recognition;
439 
440  if (avctx->codec_id == CODEC_ID_MP3ADU)
441  s->adu_mode = 1;
442 
444  avctx->coded_frame = &s->frame;
445 
446  return 0;
447 }
448 
449 #define C3 FIXHR(0.86602540378443864676/2)
450 #define C4 FIXHR(0.70710678118654752439/2) //0.5 / cos(pi*(9)/36)
451 #define C5 FIXHR(0.51763809020504152469/2) //0.5 / cos(pi*(5)/36)
452 #define C6 FIXHR(1.93185165257813657349/4) //0.5 / cos(pi*(15)/36)
453 
454 /* 12 points IMDCT. We compute it "by hand" by factorizing obvious
455  cases. */
456 static void imdct12(INTFLOAT *out, INTFLOAT *in)
457 {
458  INTFLOAT in0, in1, in2, in3, in4, in5, t1, t2;
459 
460  in0 = in[0*3];
461  in1 = in[1*3] + in[0*3];
462  in2 = in[2*3] + in[1*3];
463  in3 = in[3*3] + in[2*3];
464  in4 = in[4*3] + in[3*3];
465  in5 = in[5*3] + in[4*3];
466  in5 += in3;
467  in3 += in1;
468 
469  in2 = MULH3(in2, C3, 2);
470  in3 = MULH3(in3, C3, 4);
471 
472  t1 = in0 - in4;
473  t2 = MULH3(in1 - in5, C4, 2);
474 
475  out[ 7] =
476  out[10] = t1 + t2;
477  out[ 1] =
478  out[ 4] = t1 - t2;
479 
480  in0 += SHR(in4, 1);
481  in4 = in0 + in2;
482  in5 += 2*in1;
483  in1 = MULH3(in5 + in3, C5, 1);
484  out[ 8] =
485  out[ 9] = in4 + in1;
486  out[ 2] =
487  out[ 3] = in4 - in1;
488 
489  in0 -= in2;
490  in5 = MULH3(in5 - in3, C6, 2);
491  out[ 0] =
492  out[ 5] = in0 - in5;
493  out[ 6] =
494  out[11] = in0 + in5;
495 }
496 
497 /* return the number of decoded frames */
499 {
500  int bound, i, v, n, ch, j, mant;
501  uint8_t allocation[MPA_MAX_CHANNELS][SBLIMIT];
502  uint8_t scale_factors[MPA_MAX_CHANNELS][SBLIMIT];
503 
504  if (s->mode == MPA_JSTEREO)
505  bound = (s->mode_ext + 1) * 4;
506  else
507  bound = SBLIMIT;
508 
509  /* allocation bits */
510  for (i = 0; i < bound; i++) {
511  for (ch = 0; ch < s->nb_channels; ch++) {
512  allocation[ch][i] = get_bits(&s->gb, 4);
513  }
514  }
515  for (i = bound; i < SBLIMIT; i++)
516  allocation[0][i] = get_bits(&s->gb, 4);
517 
518  /* scale factors */
519  for (i = 0; i < bound; i++) {
520  for (ch = 0; ch < s->nb_channels; ch++) {
521  if (allocation[ch][i])
522  scale_factors[ch][i] = get_bits(&s->gb, 6);
523  }
524  }
525  for (i = bound; i < SBLIMIT; i++) {
526  if (allocation[0][i]) {
527  scale_factors[0][i] = get_bits(&s->gb, 6);
528  scale_factors[1][i] = get_bits(&s->gb, 6);
529  }
530  }
531 
532  /* compute samples */
533  for (j = 0; j < 12; j++) {
534  for (i = 0; i < bound; i++) {
535  for (ch = 0; ch < s->nb_channels; ch++) {
536  n = allocation[ch][i];
537  if (n) {
538  mant = get_bits(&s->gb, n + 1);
539  v = l1_unscale(n, mant, scale_factors[ch][i]);
540  } else {
541  v = 0;
542  }
543  s->sb_samples[ch][j][i] = v;
544  }
545  }
546  for (i = bound; i < SBLIMIT; i++) {
547  n = allocation[0][i];
548  if (n) {
549  mant = get_bits(&s->gb, n + 1);
550  v = l1_unscale(n, mant, scale_factors[0][i]);
551  s->sb_samples[0][j][i] = v;
552  v = l1_unscale(n, mant, scale_factors[1][i]);
553  s->sb_samples[1][j][i] = v;
554  } else {
555  s->sb_samples[0][j][i] = 0;
556  s->sb_samples[1][j][i] = 0;
557  }
558  }
559  }
560  return 12;
561 }
562 
564 {
565  int sblimit; /* number of used subbands */
566  const unsigned char *alloc_table;
567  int table, bit_alloc_bits, i, j, ch, bound, v;
568  unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT];
569  unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];
570  unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3], *sf;
571  int scale, qindex, bits, steps, k, l, m, b;
572 
573  /* select decoding table */
574  table = ff_mpa_l2_select_table(s->bit_rate / 1000, s->nb_channels,
575  s->sample_rate, s->lsf);
576  sblimit = ff_mpa_sblimit_table[table];
577  alloc_table = ff_mpa_alloc_tables[table];
578 
579  if (s->mode == MPA_JSTEREO)
580  bound = (s->mode_ext + 1) * 4;
581  else
582  bound = sblimit;
583 
584  av_dlog(s->avctx, "bound=%d sblimit=%d\n", bound, sblimit);
585 
586  /* sanity check */
587  if (bound > sblimit)
588  bound = sblimit;
589 
590  /* parse bit allocation */
591  j = 0;
592  for (i = 0; i < bound; i++) {
593  bit_alloc_bits = alloc_table[j];
594  for (ch = 0; ch < s->nb_channels; ch++)
595  bit_alloc[ch][i] = get_bits(&s->gb, bit_alloc_bits);
596  j += 1 << bit_alloc_bits;
597  }
598  for (i = bound; i < sblimit; i++) {
599  bit_alloc_bits = alloc_table[j];
600  v = get_bits(&s->gb, bit_alloc_bits);
601  bit_alloc[0][i] = v;
602  bit_alloc[1][i] = v;
603  j += 1 << bit_alloc_bits;
604  }
605 
606  /* scale codes */
607  for (i = 0; i < sblimit; i++) {
608  for (ch = 0; ch < s->nb_channels; ch++) {
609  if (bit_alloc[ch][i])
610  scale_code[ch][i] = get_bits(&s->gb, 2);
611  }
612  }
613 
614  /* scale factors */
615  for (i = 0; i < sblimit; i++) {
616  for (ch = 0; ch < s->nb_channels; ch++) {
617  if (bit_alloc[ch][i]) {
618  sf = scale_factors[ch][i];
619  switch (scale_code[ch][i]) {
620  default:
621  case 0:
622  sf[0] = get_bits(&s->gb, 6);
623  sf[1] = get_bits(&s->gb, 6);
624  sf[2] = get_bits(&s->gb, 6);
625  break;
626  case 2:
627  sf[0] = get_bits(&s->gb, 6);
628  sf[1] = sf[0];
629  sf[2] = sf[0];
630  break;
631  case 1:
632  sf[0] = get_bits(&s->gb, 6);
633  sf[2] = get_bits(&s->gb, 6);
634  sf[1] = sf[0];
635  break;
636  case 3:
637  sf[0] = get_bits(&s->gb, 6);
638  sf[2] = get_bits(&s->gb, 6);
639  sf[1] = sf[2];
640  break;
641  }
642  }
643  }
644  }
645 
646  /* samples */
647  for (k = 0; k < 3; k++) {
648  for (l = 0; l < 12; l += 3) {
649  j = 0;
650  for (i = 0; i < bound; i++) {
651  bit_alloc_bits = alloc_table[j];
652  for (ch = 0; ch < s->nb_channels; ch++) {
653  b = bit_alloc[ch][i];
654  if (b) {
655  scale = scale_factors[ch][i][k];
656  qindex = alloc_table[j+b];
657  bits = ff_mpa_quant_bits[qindex];
658  if (bits < 0) {
659  int v2;
660  /* 3 values at the same time */
661  v = get_bits(&s->gb, -bits);
662  v2 = division_tabs[qindex][v];
663  steps = ff_mpa_quant_steps[qindex];
664 
665  s->sb_samples[ch][k * 12 + l + 0][i] =
666  l2_unscale_group(steps, v2 & 15, scale);
667  s->sb_samples[ch][k * 12 + l + 1][i] =
668  l2_unscale_group(steps, (v2 >> 4) & 15, scale);
669  s->sb_samples[ch][k * 12 + l + 2][i] =
670  l2_unscale_group(steps, v2 >> 8 , scale);
671  } else {
672  for (m = 0; m < 3; m++) {
673  v = get_bits(&s->gb, bits);
674  v = l1_unscale(bits - 1, v, scale);
675  s->sb_samples[ch][k * 12 + l + m][i] = v;
676  }
677  }
678  } else {
679  s->sb_samples[ch][k * 12 + l + 0][i] = 0;
680  s->sb_samples[ch][k * 12 + l + 1][i] = 0;
681  s->sb_samples[ch][k * 12 + l + 2][i] = 0;
682  }
683  }
684  /* next subband in alloc table */
685  j += 1 << bit_alloc_bits;
686  }
687  /* XXX: find a way to avoid this duplication of code */
688  for (i = bound; i < sblimit; i++) {
689  bit_alloc_bits = alloc_table[j];
690  b = bit_alloc[0][i];
691  if (b) {
692  int mant, scale0, scale1;
693  scale0 = scale_factors[0][i][k];
694  scale1 = scale_factors[1][i][k];
695  qindex = alloc_table[j+b];
696  bits = ff_mpa_quant_bits[qindex];
697  if (bits < 0) {
698  /* 3 values at the same time */
699  v = get_bits(&s->gb, -bits);
700  steps = ff_mpa_quant_steps[qindex];
701  mant = v % steps;
702  v = v / steps;
703  s->sb_samples[0][k * 12 + l + 0][i] =
704  l2_unscale_group(steps, mant, scale0);
705  s->sb_samples[1][k * 12 + l + 0][i] =
706  l2_unscale_group(steps, mant, scale1);
707  mant = v % steps;
708  v = v / steps;
709  s->sb_samples[0][k * 12 + l + 1][i] =
710  l2_unscale_group(steps, mant, scale0);
711  s->sb_samples[1][k * 12 + l + 1][i] =
712  l2_unscale_group(steps, mant, scale1);
713  s->sb_samples[0][k * 12 + l + 2][i] =
714  l2_unscale_group(steps, v, scale0);
715  s->sb_samples[1][k * 12 + l + 2][i] =
716  l2_unscale_group(steps, v, scale1);
717  } else {
718  for (m = 0; m < 3; m++) {
719  mant = get_bits(&s->gb, bits);
720  s->sb_samples[0][k * 12 + l + m][i] =
721  l1_unscale(bits - 1, mant, scale0);
722  s->sb_samples[1][k * 12 + l + m][i] =
723  l1_unscale(bits - 1, mant, scale1);
724  }
725  }
726  } else {
727  s->sb_samples[0][k * 12 + l + 0][i] = 0;
728  s->sb_samples[0][k * 12 + l + 1][i] = 0;
729  s->sb_samples[0][k * 12 + l + 2][i] = 0;
730  s->sb_samples[1][k * 12 + l + 0][i] = 0;
731  s->sb_samples[1][k * 12 + l + 1][i] = 0;
732  s->sb_samples[1][k * 12 + l + 2][i] = 0;
733  }
734  /* next subband in alloc table */
735  j += 1 << bit_alloc_bits;
736  }
737  /* fill remaining samples to zero */
738  for (i = sblimit; i < SBLIMIT; i++) {
739  for (ch = 0; ch < s->nb_channels; ch++) {
740  s->sb_samples[ch][k * 12 + l + 0][i] = 0;
741  s->sb_samples[ch][k * 12 + l + 1][i] = 0;
742  s->sb_samples[ch][k * 12 + l + 2][i] = 0;
743  }
744  }
745  }
746  }
747  return 3 * 12;
748 }
749 
750 #define SPLIT(dst,sf,n) \
751  if (n == 3) { \
752  int m = (sf * 171) >> 9; \
753  dst = sf - 3 * m; \
754  sf = m; \
755  } else if (n == 4) { \
756  dst = sf & 3; \
757  sf >>= 2; \
758  } else if (n == 5) { \
759  int m = (sf * 205) >> 10; \
760  dst = sf - 5 * m; \
761  sf = m; \
762  } else if (n == 6) { \
763  int m = (sf * 171) >> 10; \
764  dst = sf - 6 * m; \
765  sf = m; \
766  } else { \
767  dst = 0; \
768  }
769 
770 static av_always_inline void lsf_sf_expand(int *slen, int sf, int n1, int n2,
771  int n3)
772 {
773  SPLIT(slen[3], sf, n3)
774  SPLIT(slen[2], sf, n2)
775  SPLIT(slen[1], sf, n1)
776  slen[0] = sf;
777 }
778 
780  int16_t *exponents)
781 {
782  const uint8_t *bstab, *pretab;
783  int len, i, j, k, l, v0, shift, gain, gains[3];
784  int16_t *exp_ptr;
785 
786  exp_ptr = exponents;
787  gain = g->global_gain - 210;
788  shift = g->scalefac_scale + 1;
789 
790  bstab = band_size_long[s->sample_rate_index];
791  pretab = mpa_pretab[g->preflag];
792  for (i = 0; i < g->long_end; i++) {
793  v0 = gain - ((g->scale_factors[i] + pretab[i]) << shift) + 400;
794  len = bstab[i];
795  for (j = len; j > 0; j--)
796  *exp_ptr++ = v0;
797  }
798 
799  if (g->short_start < 13) {
800  bstab = band_size_short[s->sample_rate_index];
801  gains[0] = gain - (g->subblock_gain[0] << 3);
802  gains[1] = gain - (g->subblock_gain[1] << 3);
803  gains[2] = gain - (g->subblock_gain[2] << 3);
804  k = g->long_end;
805  for (i = g->short_start; i < 13; i++) {
806  len = bstab[i];
807  for (l = 0; l < 3; l++) {
808  v0 = gains[l] - (g->scale_factors[k++] << shift) + 400;
809  for (j = len; j > 0; j--)
810  *exp_ptr++ = v0;
811  }
812  }
813  }
814 }
815 
816 /* handle n = 0 too */
817 static inline int get_bitsz(GetBitContext *s, int n)
818 {
819  return n ? get_bits(s, n) : 0;
820 }
821 
822 
823 static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos,
824  int *end_pos2)
825 {
826  if (s->in_gb.buffer && *pos >= s->gb.size_in_bits) {
827  s->gb = s->in_gb;
828  s->in_gb.buffer = NULL;
829  assert((get_bits_count(&s->gb) & 7) == 0);
830  skip_bits_long(&s->gb, *pos - *end_pos);
831  *end_pos2 =
832  *end_pos = *end_pos2 + get_bits_count(&s->gb) - *pos;
833  *pos = get_bits_count(&s->gb);
834  }
835 }
836 
837 /* Following is a optimized code for
838  INTFLOAT v = *src
839  if(get_bits1(&s->gb))
840  v = -v;
841  *dst = v;
842 */
843 #if CONFIG_FLOAT
844 #define READ_FLIP_SIGN(dst,src) \
845  v = AV_RN32A(src) ^ (get_bits1(&s->gb) << 31); \
846  AV_WN32A(dst, v);
847 #else
848 #define READ_FLIP_SIGN(dst,src) \
849  v = -get_bits1(&s->gb); \
850  *(dst) = (*(src) ^ v) - v;
851 #endif
852 
854  int16_t *exponents, int end_pos2)
855 {
856  int s_index;
857  int i;
858  int last_pos, bits_left;
859  VLC *vlc;
860  int end_pos = FFMIN(end_pos2, s->gb.size_in_bits);
861 
862  /* low frequencies (called big values) */
863  s_index = 0;
864  for (i = 0; i < 3; i++) {
865  int j, k, l, linbits;
866  j = g->region_size[i];
867  if (j == 0)
868  continue;
869  /* select vlc table */
870  k = g->table_select[i];
871  l = mpa_huff_data[k][0];
872  linbits = mpa_huff_data[k][1];
873  vlc = &huff_vlc[l];
874 
875  if (!l) {
876  memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid) * 2 * j);
877  s_index += 2 * j;
878  continue;
879  }
880 
881  /* read huffcode and compute each couple */
882  for (; j > 0; j--) {
883  int exponent, x, y;
884  int v;
885  int pos = get_bits_count(&s->gb);
886 
887  if (pos >= end_pos){
888 // av_log(NULL, AV_LOG_ERROR, "pos: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
889  switch_buffer(s, &pos, &end_pos, &end_pos2);
890 // av_log(NULL, AV_LOG_ERROR, "new pos: %d %d\n", pos, end_pos);
891  if (pos >= end_pos)
892  break;
893  }
894  y = get_vlc2(&s->gb, vlc->table, 7, 3);
895 
896  if (!y) {
897  g->sb_hybrid[s_index ] =
898  g->sb_hybrid[s_index+1] = 0;
899  s_index += 2;
900  continue;
901  }
902 
903  exponent= exponents[s_index];
904 
905  av_dlog(s->avctx, "region=%d n=%d x=%d y=%d exp=%d\n",
906  i, g->region_size[i] - j, x, y, exponent);
907  if (y & 16) {
908  x = y >> 5;
909  y = y & 0x0f;
910  if (x < 15) {
911  READ_FLIP_SIGN(g->sb_hybrid + s_index, RENAME(expval_table)[exponent] + x)
912  } else {
913  x += get_bitsz(&s->gb, linbits);
914  v = l3_unscale(x, exponent);
915  if (get_bits1(&s->gb))
916  v = -v;
917  g->sb_hybrid[s_index] = v;
918  }
919  if (y < 15) {
920  READ_FLIP_SIGN(g->sb_hybrid + s_index + 1, RENAME(expval_table)[exponent] + y)
921  } else {
922  y += get_bitsz(&s->gb, linbits);
923  v = l3_unscale(y, exponent);
924  if (get_bits1(&s->gb))
925  v = -v;
926  g->sb_hybrid[s_index+1] = v;
927  }
928  } else {
929  x = y >> 5;
930  y = y & 0x0f;
931  x += y;
932  if (x < 15) {
933  READ_FLIP_SIGN(g->sb_hybrid + s_index + !!y, RENAME(expval_table)[exponent] + x)
934  } else {
935  x += get_bitsz(&s->gb, linbits);
936  v = l3_unscale(x, exponent);
937  if (get_bits1(&s->gb))
938  v = -v;
939  g->sb_hybrid[s_index+!!y] = v;
940  }
941  g->sb_hybrid[s_index + !y] = 0;
942  }
943  s_index += 2;
944  }
945  }
946 
947  /* high frequencies */
948  vlc = &huff_quad_vlc[g->count1table_select];
949  last_pos = 0;
950  while (s_index <= 572) {
951  int pos, code;
952  pos = get_bits_count(&s->gb);
953  if (pos >= end_pos) {
954  if (pos > end_pos2 && last_pos) {
955  /* some encoders generate an incorrect size for this
956  part. We must go back into the data */
957  s_index -= 4;
958  skip_bits_long(&s->gb, last_pos - pos);
959  av_log(s->avctx, AV_LOG_INFO, "overread, skip %d enddists: %d %d\n", last_pos - pos, end_pos-pos, end_pos2-pos);
961  s_index=0;
962  break;
963  }
964 // av_log(NULL, AV_LOG_ERROR, "pos2: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
965  switch_buffer(s, &pos, &end_pos, &end_pos2);
966 // av_log(NULL, AV_LOG_ERROR, "new pos2: %d %d %d\n", pos, end_pos, s_index);
967  if (pos >= end_pos)
968  break;
969  }
970  last_pos = pos;
971 
972  code = get_vlc2(&s->gb, vlc->table, vlc->bits, 1);
973  av_dlog(s->avctx, "t=%d code=%d\n", g->count1table_select, code);
974  g->sb_hybrid[s_index+0] =
975  g->sb_hybrid[s_index+1] =
976  g->sb_hybrid[s_index+2] =
977  g->sb_hybrid[s_index+3] = 0;
978  while (code) {
979  static const int idxtab[16] = { 3,3,2,2,1,1,1,1,0,0,0,0,0,0,0,0 };
980  int v;
981  int pos = s_index + idxtab[code];
982  code ^= 8 >> idxtab[code];
983  READ_FLIP_SIGN(g->sb_hybrid + pos, RENAME(exp_table)+exponents[pos])
984  }
985  s_index += 4;
986  }
987  /* skip extension bits */
988  bits_left = end_pos2 - get_bits_count(&s->gb);
989 //av_log(NULL, AV_LOG_ERROR, "left:%d buf:%p\n", bits_left, s->in_gb.buffer);
990  if (bits_left < 0 && (s->err_recognition & AV_EF_BUFFER)) {
991  av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);
992  s_index=0;
993  } else if (bits_left > 0 && (s->err_recognition & AV_EF_BUFFER)) {
994  av_log(s->avctx, AV_LOG_ERROR, "bits_left=%d\n", bits_left);
995  s_index = 0;
996  }
997  memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid) * (576 - s_index));
998  skip_bits_long(&s->gb, bits_left);
999 
1000  i = get_bits_count(&s->gb);
1001  switch_buffer(s, &i, &end_pos, &end_pos2);
1002 
1003  return 0;
1004 }
1005 
1006 /* Reorder short blocks from bitstream order to interleaved order. It
1007  would be faster to do it in parsing, but the code would be far more
1008  complicated */
1010 {
1011  int i, j, len;
1012  INTFLOAT *ptr, *dst, *ptr1;
1013  INTFLOAT tmp[576];
1014 
1015  if (g->block_type != 2)
1016  return;
1017 
1018  if (g->switch_point) {
1019  if (s->sample_rate_index != 8)
1020  ptr = g->sb_hybrid + 36;
1021  else
1022  ptr = g->sb_hybrid + 48;
1023  } else {
1024  ptr = g->sb_hybrid;
1025  }
1026 
1027  for (i = g->short_start; i < 13; i++) {
1028  len = band_size_short[s->sample_rate_index][i];
1029  ptr1 = ptr;
1030  dst = tmp;
1031  for (j = len; j > 0; j--) {
1032  *dst++ = ptr[0*len];
1033  *dst++ = ptr[1*len];
1034  *dst++ = ptr[2*len];
1035  ptr++;
1036  }
1037  ptr += 2 * len;
1038  memcpy(ptr1, tmp, len * 3 * sizeof(*ptr1));
1039  }
1040 }
1041 
1042 #define ISQRT2 FIXR(0.70710678118654752440)
1043 
1045 {
1046  int i, j, k, l;
1047  int sf_max, sf, len, non_zero_found;
1048  INTFLOAT (*is_tab)[16], *tab0, *tab1, tmp0, tmp1, v1, v2;
1049  int non_zero_found_short[3];
1050 
1051  /* intensity stereo */
1052  if (s->mode_ext & MODE_EXT_I_STEREO) {
1053  if (!s->lsf) {
1054  is_tab = is_table;
1055  sf_max = 7;
1056  } else {
1057  is_tab = is_table_lsf[g1->scalefac_compress & 1];
1058  sf_max = 16;
1059  }
1060 
1061  tab0 = g0->sb_hybrid + 576;
1062  tab1 = g1->sb_hybrid + 576;
1063 
1064  non_zero_found_short[0] = 0;
1065  non_zero_found_short[1] = 0;
1066  non_zero_found_short[2] = 0;
1067  k = (13 - g1->short_start) * 3 + g1->long_end - 3;
1068  for (i = 12; i >= g1->short_start; i--) {
1069  /* for last band, use previous scale factor */
1070  if (i != 11)
1071  k -= 3;
1072  len = band_size_short[s->sample_rate_index][i];
1073  for (l = 2; l >= 0; l--) {
1074  tab0 -= len;
1075  tab1 -= len;
1076  if (!non_zero_found_short[l]) {
1077  /* test if non zero band. if so, stop doing i-stereo */
1078  for (j = 0; j < len; j++) {
1079  if (tab1[j] != 0) {
1080  non_zero_found_short[l] = 1;
1081  goto found1;
1082  }
1083  }
1084  sf = g1->scale_factors[k + l];
1085  if (sf >= sf_max)
1086  goto found1;
1087 
1088  v1 = is_tab[0][sf];
1089  v2 = is_tab[1][sf];
1090  for (j = 0; j < len; j++) {
1091  tmp0 = tab0[j];
1092  tab0[j] = MULLx(tmp0, v1, FRAC_BITS);
1093  tab1[j] = MULLx(tmp0, v2, FRAC_BITS);
1094  }
1095  } else {
1096 found1:
1097  if (s->mode_ext & MODE_EXT_MS_STEREO) {
1098  /* lower part of the spectrum : do ms stereo
1099  if enabled */
1100  for (j = 0; j < len; j++) {
1101  tmp0 = tab0[j];
1102  tmp1 = tab1[j];
1103  tab0[j] = MULLx(tmp0 + tmp1, ISQRT2, FRAC_BITS);
1104  tab1[j] = MULLx(tmp0 - tmp1, ISQRT2, FRAC_BITS);
1105  }
1106  }
1107  }
1108  }
1109  }
1110 
1111  non_zero_found = non_zero_found_short[0] |
1112  non_zero_found_short[1] |
1113  non_zero_found_short[2];
1114 
1115  for (i = g1->long_end - 1;i >= 0;i--) {
1116  len = band_size_long[s->sample_rate_index][i];
1117  tab0 -= len;
1118  tab1 -= len;
1119  /* test if non zero band. if so, stop doing i-stereo */
1120  if (!non_zero_found) {
1121  for (j = 0; j < len; j++) {
1122  if (tab1[j] != 0) {
1123  non_zero_found = 1;
1124  goto found2;
1125  }
1126  }
1127  /* for last band, use previous scale factor */
1128  k = (i == 21) ? 20 : i;
1129  sf = g1->scale_factors[k];
1130  if (sf >= sf_max)
1131  goto found2;
1132  v1 = is_tab[0][sf];
1133  v2 = is_tab[1][sf];
1134  for (j = 0; j < len; j++) {
1135  tmp0 = tab0[j];
1136  tab0[j] = MULLx(tmp0, v1, FRAC_BITS);
1137  tab1[j] = MULLx(tmp0, v2, FRAC_BITS);
1138  }
1139  } else {
1140 found2:
1141  if (s->mode_ext & MODE_EXT_MS_STEREO) {
1142  /* lower part of the spectrum : do ms stereo
1143  if enabled */
1144  for (j = 0; j < len; j++) {
1145  tmp0 = tab0[j];
1146  tmp1 = tab1[j];
1147  tab0[j] = MULLx(tmp0 + tmp1, ISQRT2, FRAC_BITS);
1148  tab1[j] = MULLx(tmp0 - tmp1, ISQRT2, FRAC_BITS);
1149  }
1150  }
1151  }
1152  }
1153  } else if (s->mode_ext & MODE_EXT_MS_STEREO) {
1154  /* ms stereo ONLY */
1155  /* NOTE: the 1/sqrt(2) normalization factor is included in the
1156  global gain */
1157  tab0 = g0->sb_hybrid;
1158  tab1 = g1->sb_hybrid;
1159  for (i = 0; i < 576; i++) {
1160  tmp0 = tab0[i];
1161  tmp1 = tab1[i];
1162  tab0[i] = tmp0 + tmp1;
1163  tab1[i] = tmp0 - tmp1;
1164  }
1165  }
1166 }
1167 
1168 #if CONFIG_FLOAT
1169 #define AA(j) do { \
1170  float tmp0 = ptr[-1-j]; \
1171  float tmp1 = ptr[ j]; \
1172  ptr[-1-j] = tmp0 * csa_table[j][0] - tmp1 * csa_table[j][1]; \
1173  ptr[ j] = tmp0 * csa_table[j][1] + tmp1 * csa_table[j][0]; \
1174  } while (0)
1175 #else
1176 #define AA(j) do { \
1177  int tmp0 = ptr[-1-j]; \
1178  int tmp1 = ptr[ j]; \
1179  int tmp2 = MULH(tmp0 + tmp1, csa_table[j][0]); \
1180  ptr[-1-j] = 4 * (tmp2 - MULH(tmp1, csa_table[j][2])); \
1181  ptr[ j] = 4 * (tmp2 + MULH(tmp0, csa_table[j][3])); \
1182  } while (0)
1183 #endif
1184 
1186 {
1187  INTFLOAT *ptr;
1188  int n, i;
1189 
1190  /* we antialias only "long" bands */
1191  if (g->block_type == 2) {
1192  if (!g->switch_point)
1193  return;
1194  /* XXX: check this for 8000Hz case */
1195  n = 1;
1196  } else {
1197  n = SBLIMIT - 1;
1198  }
1199 
1200  ptr = g->sb_hybrid + 18;
1201  for (i = n; i > 0; i--) {
1202  AA(0);
1203  AA(1);
1204  AA(2);
1205  AA(3);
1206  AA(4);
1207  AA(5);
1208  AA(6);
1209  AA(7);
1210 
1211  ptr += 18;
1212  }
1213 }
1214 
1216  INTFLOAT *sb_samples, INTFLOAT *mdct_buf)
1217 {
1218  INTFLOAT *win, *out_ptr, *ptr, *buf, *ptr1;
1219  INTFLOAT out2[12];
1220  int i, j, mdct_long_end, sblimit;
1221 
1222  /* find last non zero block */
1223  ptr = g->sb_hybrid + 576;
1224  ptr1 = g->sb_hybrid + 2 * 18;
1225  while (ptr >= ptr1) {
1226  int32_t *p;
1227  ptr -= 6;
1228  p = (int32_t*)ptr;
1229  if (p[0] | p[1] | p[2] | p[3] | p[4] | p[5])
1230  break;
1231  }
1232  sblimit = ((ptr - g->sb_hybrid) / 18) + 1;
1233 
1234  if (g->block_type == 2) {
1235  /* XXX: check for 8000 Hz */
1236  if (g->switch_point)
1237  mdct_long_end = 2;
1238  else
1239  mdct_long_end = 0;
1240  } else {
1241  mdct_long_end = sblimit;
1242  }
1243 
1244  s->mpadsp.RENAME(imdct36_blocks)(sb_samples, mdct_buf, g->sb_hybrid,
1245  mdct_long_end, g->switch_point,
1246  g->block_type);
1247 
1248  buf = mdct_buf + 4*18*(mdct_long_end >> 2) + (mdct_long_end & 3);
1249  ptr = g->sb_hybrid + 18 * mdct_long_end;
1250 
1251  for (j = mdct_long_end; j < sblimit; j++) {
1252  /* select frequency inversion */
1253  win = RENAME(ff_mdct_win)[2 + (4 & -(j & 1))];
1254  out_ptr = sb_samples + j;
1255 
1256  for (i = 0; i < 6; i++) {
1257  *out_ptr = buf[4*i];
1258  out_ptr += SBLIMIT;
1259  }
1260  imdct12(out2, ptr + 0);
1261  for (i = 0; i < 6; i++) {
1262  *out_ptr = MULH3(out2[i ], win[i ], 1) + buf[4*(i + 6*1)];
1263  buf[4*(i + 6*2)] = MULH3(out2[i + 6], win[i + 6], 1);
1264  out_ptr += SBLIMIT;
1265  }
1266  imdct12(out2, ptr + 1);
1267  for (i = 0; i < 6; i++) {
1268  *out_ptr = MULH3(out2[i ], win[i ], 1) + buf[4*(i + 6*2)];
1269  buf[4*(i + 6*0)] = MULH3(out2[i + 6], win[i + 6], 1);
1270  out_ptr += SBLIMIT;
1271  }
1272  imdct12(out2, ptr + 2);
1273  for (i = 0; i < 6; i++) {
1274  buf[4*(i + 6*0)] = MULH3(out2[i ], win[i ], 1) + buf[4*(i + 6*0)];
1275  buf[4*(i + 6*1)] = MULH3(out2[i + 6], win[i + 6], 1);
1276  buf[4*(i + 6*2)] = 0;
1277  }
1278  ptr += 18;
1279  buf += (j&3) != 3 ? 1 : (4*18-3);
1280  }
1281  /* zero bands */
1282  for (j = sblimit; j < SBLIMIT; j++) {
1283  /* overlap */
1284  out_ptr = sb_samples + j;
1285  for (i = 0; i < 18; i++) {
1286  *out_ptr = buf[4*i];
1287  buf[4*i] = 0;
1288  out_ptr += SBLIMIT;
1289  }
1290  buf += (j&3) != 3 ? 1 : (4*18-3);
1291  }
1292 }
1293 
1294 /* main layer3 decoding function */
1296 {
1297  int nb_granules, main_data_begin;
1298  int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;
1299  GranuleDef *g;
1300  int16_t exponents[576]; //FIXME try INTFLOAT
1301 
1302  /* read side info */
1303  if (s->lsf) {
1304  main_data_begin = get_bits(&s->gb, 8);
1305  skip_bits(&s->gb, s->nb_channels);
1306  nb_granules = 1;
1307  } else {
1308  main_data_begin = get_bits(&s->gb, 9);
1309  if (s->nb_channels == 2)
1310  skip_bits(&s->gb, 3);
1311  else
1312  skip_bits(&s->gb, 5);
1313  nb_granules = 2;
1314  for (ch = 0; ch < s->nb_channels; ch++) {
1315  s->granules[ch][0].scfsi = 0;/* all scale factors are transmitted */
1316  s->granules[ch][1].scfsi = get_bits(&s->gb, 4);
1317  }
1318  }
1319 
1320  for (gr = 0; gr < nb_granules; gr++) {
1321  for (ch = 0; ch < s->nb_channels; ch++) {
1322  av_dlog(s->avctx, "gr=%d ch=%d: side_info\n", gr, ch);
1323  g = &s->granules[ch][gr];
1324  g->part2_3_length = get_bits(&s->gb, 12);
1325  g->big_values = get_bits(&s->gb, 9);
1326  if (g->big_values > 288) {
1327  av_log(s->avctx, AV_LOG_ERROR, "big_values too big\n");
1328  return AVERROR_INVALIDDATA;
1329  }
1330 
1331  g->global_gain = get_bits(&s->gb, 8);
1332  /* if MS stereo only is selected, we precompute the
1333  1/sqrt(2) renormalization factor */
1334  if ((s->mode_ext & (MODE_EXT_MS_STEREO | MODE_EXT_I_STEREO)) ==
1336  g->global_gain -= 2;
1337  if (s->lsf)
1338  g->scalefac_compress = get_bits(&s->gb, 9);
1339  else
1340  g->scalefac_compress = get_bits(&s->gb, 4);
1341  blocksplit_flag = get_bits1(&s->gb);
1342  if (blocksplit_flag) {
1343  g->block_type = get_bits(&s->gb, 2);
1344  if (g->block_type == 0) {
1345  av_log(s->avctx, AV_LOG_ERROR, "invalid block type\n");
1346  return AVERROR_INVALIDDATA;
1347  }
1348  g->switch_point = get_bits1(&s->gb);
1349  for (i = 0; i < 2; i++)
1350  g->table_select[i] = get_bits(&s->gb, 5);
1351  for (i = 0; i < 3; i++)
1352  g->subblock_gain[i] = get_bits(&s->gb, 3);
1353  ff_init_short_region(s, g);
1354  } else {
1355  int region_address1, region_address2;
1356  g->block_type = 0;
1357  g->switch_point = 0;
1358  for (i = 0; i < 3; i++)
1359  g->table_select[i] = get_bits(&s->gb, 5);
1360  /* compute huffman coded region sizes */
1361  region_address1 = get_bits(&s->gb, 4);
1362  region_address2 = get_bits(&s->gb, 3);
1363  av_dlog(s->avctx, "region1=%d region2=%d\n",
1364  region_address1, region_address2);
1365  ff_init_long_region(s, g, region_address1, region_address2);
1366  }
1369 
1370  g->preflag = 0;
1371  if (!s->lsf)
1372  g->preflag = get_bits1(&s->gb);
1373  g->scalefac_scale = get_bits1(&s->gb);
1374  g->count1table_select = get_bits1(&s->gb);
1375  av_dlog(s->avctx, "block_type=%d switch_point=%d\n",
1376  g->block_type, g->switch_point);
1377  }
1378  }
1379 
1380  if (!s->adu_mode) {
1381  int skip;
1382  const uint8_t *ptr = s->gb.buffer + (get_bits_count(&s->gb)>>3);
1383  int extrasize = av_clip(get_bits_left(&s->gb) >> 3, 0,
1384  FFMAX(0, LAST_BUF_SIZE - s->last_buf_size));
1385  assert((get_bits_count(&s->gb) & 7) == 0);
1386  /* now we get bits from the main_data_begin offset */
1387  av_dlog(s->avctx, "seekback: %d\n", main_data_begin);
1388  //av_log(NULL, AV_LOG_ERROR, "backstep:%d, lastbuf:%d\n", main_data_begin, s->last_buf_size);
1389 
1390  memcpy(s->last_buf + s->last_buf_size, ptr, extrasize);
1391  s->in_gb = s->gb;
1392  init_get_bits(&s->gb, s->last_buf, s->last_buf_size*8);
1393 #if !UNCHECKED_BITSTREAM_READER
1394  s->gb.size_in_bits_plus8 += extrasize * 8;
1395 #endif
1396  s->last_buf_size <<= 3;
1397  for (gr = 0; gr < nb_granules && (s->last_buf_size >> 3) < main_data_begin; gr++) {
1398  for (ch = 0; ch < s->nb_channels; ch++) {
1399  g = &s->granules[ch][gr];
1400  s->last_buf_size += g->part2_3_length;
1401  memset(g->sb_hybrid, 0, sizeof(g->sb_hybrid));
1402  }
1403  }
1404  skip = s->last_buf_size - 8 * main_data_begin;
1405  if (skip >= s->gb.size_in_bits && s->in_gb.buffer) {
1406  skip_bits_long(&s->in_gb, skip - s->gb.size_in_bits);
1407  s->gb = s->in_gb;
1408  s->in_gb.buffer = NULL;
1409  } else {
1410  skip_bits_long(&s->gb, skip);
1411  }
1412  } else {
1413  gr = 0;
1414  }
1415 
1416  for (; gr < nb_granules; gr++) {
1417  for (ch = 0; ch < s->nb_channels; ch++) {
1418  g = &s->granules[ch][gr];
1419  bits_pos = get_bits_count(&s->gb);
1420 
1421  if (!s->lsf) {
1422  uint8_t *sc;
1423  int slen, slen1, slen2;
1424 
1425  /* MPEG1 scale factors */
1426  slen1 = slen_table[0][g->scalefac_compress];
1427  slen2 = slen_table[1][g->scalefac_compress];
1428  av_dlog(s->avctx, "slen1=%d slen2=%d\n", slen1, slen2);
1429  if (g->block_type == 2) {
1430  n = g->switch_point ? 17 : 18;
1431  j = 0;
1432  if (slen1) {
1433  for (i = 0; i < n; i++)
1434  g->scale_factors[j++] = get_bits(&s->gb, slen1);
1435  } else {
1436  for (i = 0; i < n; i++)
1437  g->scale_factors[j++] = 0;
1438  }
1439  if (slen2) {
1440  for (i = 0; i < 18; i++)
1441  g->scale_factors[j++] = get_bits(&s->gb, slen2);
1442  for (i = 0; i < 3; i++)
1443  g->scale_factors[j++] = 0;
1444  } else {
1445  for (i = 0; i < 21; i++)
1446  g->scale_factors[j++] = 0;
1447  }
1448  } else {
1449  sc = s->granules[ch][0].scale_factors;
1450  j = 0;
1451  for (k = 0; k < 4; k++) {
1452  n = k == 0 ? 6 : 5;
1453  if ((g->scfsi & (0x8 >> k)) == 0) {
1454  slen = (k < 2) ? slen1 : slen2;
1455  if (slen) {
1456  for (i = 0; i < n; i++)
1457  g->scale_factors[j++] = get_bits(&s->gb, slen);
1458  } else {
1459  for (i = 0; i < n; i++)
1460  g->scale_factors[j++] = 0;
1461  }
1462  } else {
1463  /* simply copy from last granule */
1464  for (i = 0; i < n; i++) {
1465  g->scale_factors[j] = sc[j];
1466  j++;
1467  }
1468  }
1469  }
1470  g->scale_factors[j++] = 0;
1471  }
1472  } else {
1473  int tindex, tindex2, slen[4], sl, sf;
1474 
1475  /* LSF scale factors */
1476  if (g->block_type == 2)
1477  tindex = g->switch_point ? 2 : 1;
1478  else
1479  tindex = 0;
1480 
1481  sf = g->scalefac_compress;
1482  if ((s->mode_ext & MODE_EXT_I_STEREO) && ch == 1) {
1483  /* intensity stereo case */
1484  sf >>= 1;
1485  if (sf < 180) {
1486  lsf_sf_expand(slen, sf, 6, 6, 0);
1487  tindex2 = 3;
1488  } else if (sf < 244) {
1489  lsf_sf_expand(slen, sf - 180, 4, 4, 0);
1490  tindex2 = 4;
1491  } else {
1492  lsf_sf_expand(slen, sf - 244, 3, 0, 0);
1493  tindex2 = 5;
1494  }
1495  } else {
1496  /* normal case */
1497  if (sf < 400) {
1498  lsf_sf_expand(slen, sf, 5, 4, 4);
1499  tindex2 = 0;
1500  } else if (sf < 500) {
1501  lsf_sf_expand(slen, sf - 400, 5, 4, 0);
1502  tindex2 = 1;
1503  } else {
1504  lsf_sf_expand(slen, sf - 500, 3, 0, 0);
1505  tindex2 = 2;
1506  g->preflag = 1;
1507  }
1508  }
1509 
1510  j = 0;
1511  for (k = 0; k < 4; k++) {
1512  n = lsf_nsf_table[tindex2][tindex][k];
1513  sl = slen[k];
1514  if (sl) {
1515  for (i = 0; i < n; i++)
1516  g->scale_factors[j++] = get_bits(&s->gb, sl);
1517  } else {
1518  for (i = 0; i < n; i++)
1519  g->scale_factors[j++] = 0;
1520  }
1521  }
1522  /* XXX: should compute exact size */
1523  for (; j < 40; j++)
1524  g->scale_factors[j] = 0;
1525  }
1526 
1527  exponents_from_scale_factors(s, g, exponents);
1528 
1529  /* read Huffman coded residue */
1530  huffman_decode(s, g, exponents, bits_pos + g->part2_3_length);
1531  } /* ch */
1532 
1533  if (s->nb_channels == 2)
1534  compute_stereo(s, &s->granules[0][gr], &s->granules[1][gr]);
1535 
1536  for (ch = 0; ch < s->nb_channels; ch++) {
1537  g = &s->granules[ch][gr];
1538 
1539  reorder_block(s, g);
1540  compute_antialias(s, g);
1541  compute_imdct(s, g, &s->sb_samples[ch][18 * gr][0], s->mdct_buf[ch]);
1542  }
1543  } /* gr */
1544  if (get_bits_count(&s->gb) < 0)
1545  skip_bits_long(&s->gb, -get_bits_count(&s->gb));
1546  return nb_granules * 18;
1547 }
1548 
1550  const uint8_t *buf, int buf_size)
1551 {
1552  int i, nb_frames, ch, ret;
1553  OUT_INT *samples_ptr;
1554 
1555  init_get_bits(&s->gb, buf + HEADER_SIZE, (buf_size - HEADER_SIZE) * 8);
1556 
1557  /* skip error protection field */
1558  if (s->error_protection)
1559  skip_bits(&s->gb, 16);
1560 
1561  switch(s->layer) {
1562  case 1:
1563  s->avctx->frame_size = 384;
1564  nb_frames = mp_decode_layer1(s);
1565  break;
1566  case 2:
1567  s->avctx->frame_size = 1152;
1568  nb_frames = mp_decode_layer2(s);
1569  break;
1570  case 3:
1571  s->avctx->frame_size = s->lsf ? 576 : 1152;
1572  default:
1573  nb_frames = mp_decode_layer3(s);
1574 
1575  if (nb_frames < 0)
1576  return nb_frames;
1577 
1578  s->last_buf_size=0;
1579  if (s->in_gb.buffer) {
1580  align_get_bits(&s->gb);
1581  i = get_bits_left(&s->gb)>>3;
1582  if (i >= 0 && i <= BACKSTEP_SIZE) {
1583  memmove(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), i);
1584  s->last_buf_size=i;
1585  } else
1586  av_log(s->avctx, AV_LOG_ERROR, "invalid old backstep %d\n", i);
1587  s->gb = s->in_gb;
1588  s->in_gb.buffer = NULL;
1589  }
1590 
1591  align_get_bits(&s->gb);
1592  assert((get_bits_count(&s->gb) & 7) == 0);
1593  i = get_bits_left(&s->gb) >> 3;
1594 
1595  if (i < 0 || i > BACKSTEP_SIZE || nb_frames < 0) {
1596  if (i < 0)
1597  av_log(s->avctx, AV_LOG_ERROR, "invalid new backstep %d\n", i);
1598  i = FFMIN(BACKSTEP_SIZE, buf_size - HEADER_SIZE);
1599  }
1600  assert(i <= buf_size - HEADER_SIZE && i >= 0);
1601  memcpy(s->last_buf + s->last_buf_size, s->gb.buffer + buf_size - HEADER_SIZE - i, i);
1602  s->last_buf_size += i;
1603  }
1604 
1605  /* get output buffer */
1606  if (!samples) {
1607  s->frame.nb_samples = s->avctx->frame_size;
1608  if ((ret = ff_get_buffer(s->avctx, &s->frame)) < 0) {
1609  av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1610  return ret;
1611  }
1612  samples = (OUT_INT *)s->frame.data[0];
1613  }
1614 
1615  /* apply the synthesis filter */
1616  for (ch = 0; ch < s->nb_channels; ch++) {
1617  samples_ptr = samples + ch;
1618  for (i = 0; i < nb_frames; i++) {
1619  RENAME(ff_mpa_synth_filter)(
1620  &s->mpadsp,
1621  s->synth_buf[ch], &(s->synth_buf_offset[ch]),
1622  RENAME(ff_mpa_synth_window), &s->dither_state,
1623  samples_ptr, s->nb_channels,
1624  s->sb_samples[ch][i]);
1625  samples_ptr += 32 * s->nb_channels;
1626  }
1627  }
1628 
1629  return nb_frames * 32 * sizeof(OUT_INT) * s->nb_channels;
1630 }
1631 
1632 static int decode_frame(AVCodecContext * avctx, void *data, int *got_frame_ptr,
1633  AVPacket *avpkt)
1634 {
1635  const uint8_t *buf = avpkt->data;
1636  int buf_size = avpkt->size;
1637  MPADecodeContext *s = avctx->priv_data;
1638  uint32_t header;
1639  int ret;
1640 
1641  if (buf_size < HEADER_SIZE)
1642  return AVERROR_INVALIDDATA;
1643 
1644  header = AV_RB32(buf);
1645  if (ff_mpa_check_header(header) < 0) {
1646  av_log(avctx, AV_LOG_ERROR, "Header missing\n");
1647  return AVERROR_INVALIDDATA;
1648  }
1649 
1650  if (avpriv_mpegaudio_decode_header((MPADecodeHeader *)s, header) == 1) {
1651  /* free format: prepare to compute frame size */
1652  s->frame_size = -1;
1653  return AVERROR_INVALIDDATA;
1654  }
1655  /* update codec info */
1656  avctx->channels = s->nb_channels;
1657  avctx->channel_layout = s->nb_channels == 1 ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
1658  if (!avctx->bit_rate)
1659  avctx->bit_rate = s->bit_rate;
1660  avctx->sub_id = s->layer;
1661 
1662  if (s->frame_size <= 0 || s->frame_size > buf_size) {
1663  av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");
1664  return AVERROR_INVALIDDATA;
1665  } else if (s->frame_size < buf_size) {
1666  av_log(avctx, AV_LOG_ERROR, "incorrect frame size\n");
1667  buf_size= s->frame_size;
1668  }
1669 
1670  ret = mp_decode_frame(s, NULL, buf, buf_size);
1671  if (ret >= 0) {
1672  *got_frame_ptr = 1;
1673  *(AVFrame *)data = s->frame;
1674  avctx->sample_rate = s->sample_rate;
1675  //FIXME maybe move the other codec info stuff from above here too
1676  } else {
1677  av_log(avctx, AV_LOG_ERROR, "Error while decoding MPEG audio frame.\n");
1678  /* Only return an error if the bad frame makes up the whole packet or
1679  * the error is related to buffer management.
1680  * If there is more data in the packet, just consume the bad frame
1681  * instead of returning an error, which would discard the whole
1682  * packet. */
1683  *got_frame_ptr = 0;
1684  if (buf_size == avpkt->size || ret != AVERROR_INVALIDDATA)
1685  return ret;
1686  }
1687  s->frame_size = 0;
1688  return buf_size;
1689 }
1690 
1691 static void flush(AVCodecContext *avctx)
1692 {
1693  MPADecodeContext *s = avctx->priv_data;
1694  memset(s->synth_buf, 0, sizeof(s->synth_buf));
1695  s->last_buf_size = 0;
1696 }
1697 
1698 #if CONFIG_MP3ADU_DECODER || CONFIG_MP3ADUFLOAT_DECODER
1699 static int decode_frame_adu(AVCodecContext *avctx, void *data,
1700  int *got_frame_ptr, AVPacket *avpkt)
1701 {
1702  const uint8_t *buf = avpkt->data;
1703  int buf_size = avpkt->size;
1704  MPADecodeContext *s = avctx->priv_data;
1705  uint32_t header;
1706  int len, out_size, ret = 0;
1707 
1708  len = buf_size;
1709 
1710  // Discard too short frames
1711  if (buf_size < HEADER_SIZE) {
1712  av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
1713  return AVERROR_INVALIDDATA;
1714  }
1715 
1716 
1717  if (len > MPA_MAX_CODED_FRAME_SIZE)
1719 
1720  // Get header and restore sync word
1721  header = AV_RB32(buf) | 0xffe00000;
1722 
1723  if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame
1724  av_log(avctx, AV_LOG_ERROR, "Invalid frame header\n");
1725  return AVERROR_INVALIDDATA;
1726  }
1727 
1729  /* update codec info */
1730  avctx->sample_rate = s->sample_rate;
1731  avctx->channels = s->nb_channels;
1732  if (!avctx->bit_rate)
1733  avctx->bit_rate = s->bit_rate;
1734  avctx->sub_id = s->layer;
1735 
1736  s->frame_size = len;
1737 
1738 #if FF_API_PARSE_FRAME
1739  if (avctx->parse_only)
1740  out_size = buf_size;
1741  else
1742 #endif
1743  ret = mp_decode_frame(s, NULL, buf, buf_size);
1744  if (ret < 0) {
1745  av_log(avctx, AV_LOG_ERROR, "Error while decoding MPEG audio frame.\n");
1746  return ret;
1747  }
1748 
1749  *got_frame_ptr = 1;
1750  *(AVFrame *)data = s->frame;
1751 
1752  return buf_size;
1753 }
1754 #endif /* CONFIG_MP3ADU_DECODER || CONFIG_MP3ADUFLOAT_DECODER */
1755 
1756 #if CONFIG_MP3ON4_DECODER || CONFIG_MP3ON4FLOAT_DECODER
1757 
1761 typedef struct MP3On4DecodeContext {
1762  AVFrame *frame;
1763  int frames;
1764  int syncword;
1765  const uint8_t *coff;
1766  MPADecodeContext *mp3decctx[5];
1767  OUT_INT *decoded_buf;
1768 } MP3On4DecodeContext;
1769 
1770 #include "mpeg4audio.h"
1771 
1772 /* Next 3 arrays are indexed by channel config number (passed via codecdata) */
1773 
1774 /* number of mp3 decoder instances */
1775 static const uint8_t mp3Frames[8] = { 0, 1, 1, 2, 3, 3, 4, 5 };
1776 
1777 /* offsets into output buffer, assume output order is FL FR C LFE BL BR SL SR */
1778 static const uint8_t chan_offset[8][5] = {
1779  { 0 },
1780  { 0 }, // C
1781  { 0 }, // FLR
1782  { 2, 0 }, // C FLR
1783  { 2, 0, 3 }, // C FLR BS
1784  { 2, 0, 3 }, // C FLR BLRS
1785  { 2, 0, 4, 3 }, // C FLR BLRS LFE
1786  { 2, 0, 6, 4, 3 }, // C FLR BLRS BLR LFE
1787 };
1788 
1789 /* mp3on4 channel layouts */
1790 static const int16_t chan_layout[8] = {
1791  0,
1799 };
1800 
1801 static av_cold int decode_close_mp3on4(AVCodecContext * avctx)
1802 {
1803  MP3On4DecodeContext *s = avctx->priv_data;
1804  int i;
1805 
1806  for (i = 0; i < s->frames; i++)
1807  av_free(s->mp3decctx[i]);
1808 
1809  av_freep(&s->decoded_buf);
1810 
1811  return 0;
1812 }
1813 
1814 
1815 static int decode_init_mp3on4(AVCodecContext * avctx)
1816 {
1817  MP3On4DecodeContext *s = avctx->priv_data;
1818  MPEG4AudioConfig cfg;
1819  int i;
1820 
1821  if ((avctx->extradata_size < 2) || (avctx->extradata == NULL)) {
1822  av_log(avctx, AV_LOG_ERROR, "Codec extradata missing or too short.\n");
1823  return AVERROR_INVALIDDATA;
1824  }
1825 
1827  avctx->extradata_size * 8, 1);
1828  if (!cfg.chan_config || cfg.chan_config > 7) {
1829  av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");
1830  return AVERROR_INVALIDDATA;
1831  }
1832  s->frames = mp3Frames[cfg.chan_config];
1833  s->coff = chan_offset[cfg.chan_config];
1835  avctx->channel_layout = chan_layout[cfg.chan_config];
1836 
1837  if (cfg.sample_rate < 16000)
1838  s->syncword = 0xffe00000;
1839  else
1840  s->syncword = 0xfff00000;
1841 
1842  /* Init the first mp3 decoder in standard way, so that all tables get builded
1843  * We replace avctx->priv_data with the context of the first decoder so that
1844  * decode_init() does not have to be changed.
1845  * Other decoders will be initialized here copying data from the first context
1846  */
1847  // Allocate zeroed memory for the first decoder context
1848  s->mp3decctx[0] = av_mallocz(sizeof(MPADecodeContext));
1849  if (!s->mp3decctx[0])
1850  goto alloc_fail;
1851  // Put decoder context in place to make init_decode() happy
1852  avctx->priv_data = s->mp3decctx[0];
1853  decode_init(avctx);
1854  s->frame = avctx->coded_frame;
1855  // Restore mp3on4 context pointer
1856  avctx->priv_data = s;
1857  s->mp3decctx[0]->adu_mode = 1; // Set adu mode
1858 
1859  /* Create a separate codec/context for each frame (first is already ok).
1860  * Each frame is 1 or 2 channels - up to 5 frames allowed
1861  */
1862  for (i = 1; i < s->frames; i++) {
1863  s->mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));
1864  if (!s->mp3decctx[i])
1865  goto alloc_fail;
1866  s->mp3decctx[i]->adu_mode = 1;
1867  s->mp3decctx[i]->avctx = avctx;
1868  s->mp3decctx[i]->mpadsp = s->mp3decctx[0]->mpadsp;
1869  }
1870 
1871  /* Allocate buffer for multi-channel output if needed */
1872  if (s->frames > 1) {
1873  s->decoded_buf = av_malloc(MPA_FRAME_SIZE * MPA_MAX_CHANNELS *
1874  sizeof(*s->decoded_buf));
1875  if (!s->decoded_buf)
1876  goto alloc_fail;
1877  }
1878 
1879  return 0;
1880 alloc_fail:
1881  decode_close_mp3on4(avctx);
1882  return AVERROR(ENOMEM);
1883 }
1884 
1885 
1886 static void flush_mp3on4(AVCodecContext *avctx)
1887 {
1888  int i;
1889  MP3On4DecodeContext *s = avctx->priv_data;
1890 
1891  for (i = 0; i < s->frames; i++) {
1892  MPADecodeContext *m = s->mp3decctx[i];
1893  memset(m->synth_buf, 0, sizeof(m->synth_buf));
1894  m->last_buf_size = 0;
1895  }
1896 }
1897 
1898 
1899 static int decode_frame_mp3on4(AVCodecContext *avctx, void *data,
1900  int *got_frame_ptr, AVPacket *avpkt)
1901 {
1902  const uint8_t *buf = avpkt->data;
1903  int buf_size = avpkt->size;
1904  MP3On4DecodeContext *s = avctx->priv_data;
1905  MPADecodeContext *m;
1906  int fsize, len = buf_size, out_size = 0;
1907  uint32_t header;
1908  OUT_INT *out_samples;
1909  OUT_INT *outptr, *bp;
1910  int fr, j, n, ch, ret;
1911 
1912  /* get output buffer */
1913  s->frame->nb_samples = MPA_FRAME_SIZE;
1914  if ((ret = ff_get_buffer(avctx, s->frame)) < 0) {
1915  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1916  return ret;
1917  }
1918  out_samples = (OUT_INT *)s->frame->data[0];
1919 
1920  // Discard too short frames
1921  if (buf_size < HEADER_SIZE)
1922  return AVERROR_INVALIDDATA;
1923 
1924  // If only one decoder interleave is not needed
1925  outptr = s->frames == 1 ? out_samples : s->decoded_buf;
1926 
1927  avctx->bit_rate = 0;
1928 
1929  ch = 0;
1930  for (fr = 0; fr < s->frames; fr++) {
1931  fsize = AV_RB16(buf) >> 4;
1932  fsize = FFMIN3(fsize, len, MPA_MAX_CODED_FRAME_SIZE);
1933  m = s->mp3decctx[fr];
1934  assert(m != NULL);
1935 
1936  if (fsize < HEADER_SIZE) {
1937  av_log(avctx, AV_LOG_ERROR, "Frame size smaller than header size\n");
1938  return AVERROR_INVALIDDATA;
1939  }
1940  header = (AV_RB32(buf) & 0x000fffff) | s->syncword; // patch header
1941 
1942  if (ff_mpa_check_header(header) < 0) // Bad header, discard block
1943  break;
1944 
1946 
1947  if (ch + m->nb_channels > avctx->channels ||
1948  s->coff[fr] + m->nb_channels > avctx->channels) {
1949  av_log(avctx, AV_LOG_ERROR, "frame channel count exceeds codec "
1950  "channel count\n");
1951  return AVERROR_INVALIDDATA;
1952  }
1953  ch += m->nb_channels;
1954 
1955  if ((ret = mp_decode_frame(m, outptr, buf, fsize)) < 0)
1956  return ret;
1957 
1958  out_size += ret;
1959  buf += fsize;
1960  len -= fsize;
1961 
1962  if (s->frames > 1) {
1963  n = m->avctx->frame_size*m->nb_channels;
1964  /* interleave output data */
1965  bp = out_samples + s->coff[fr];
1966  if (m->nb_channels == 1) {
1967  for (j = 0; j < n; j++) {
1968  *bp = s->decoded_buf[j];
1969  bp += avctx->channels;
1970  }
1971  } else {
1972  for (j = 0; j < n; j++) {
1973  bp[0] = s->decoded_buf[j++];
1974  bp[1] = s->decoded_buf[j];
1975  bp += avctx->channels;
1976  }
1977  }
1978  }
1979  avctx->bit_rate += m->bit_rate;
1980  }
1981 
1982  /* update codec info */
1983  avctx->sample_rate = s->mp3decctx[0]->sample_rate;
1984 
1985  s->frame->nb_samples = out_size / (avctx->channels * sizeof(OUT_INT));
1986  *got_frame_ptr = 1;
1987  *(AVFrame *)data = *s->frame;
1988 
1989  return buf_size;
1990 }
1991 #endif /* CONFIG_MP3ON4_DECODER || CONFIG_MP3ON4FLOAT_DECODER */
1992 
1993 #if !CONFIG_FLOAT
1994 #if CONFIG_MP1_DECODER
1995 AVCodec ff_mp1_decoder = {
1996  .name = "mp1",
1997  .type = AVMEDIA_TYPE_AUDIO,
1998  .id = CODEC_ID_MP1,
1999  .priv_data_size = sizeof(MPADecodeContext),
2000  .init = decode_init,
2001  .decode = decode_frame,
2003  .capabilities = CODEC_CAP_PARSE_ONLY | CODEC_CAP_DR1,
2004 #else
2005  .capabilities = CODEC_CAP_DR1,
2006 #endif
2007  .flush = flush,
2008  .long_name = NULL_IF_CONFIG_SMALL("MP1 (MPEG audio layer 1)"),
2009 };
2010 #endif
2011 #if CONFIG_MP2_DECODER
2012 AVCodec ff_mp2_decoder = {
2013  .name = "mp2",
2014  .type = AVMEDIA_TYPE_AUDIO,
2015  .id = CODEC_ID_MP2,
2016  .priv_data_size = sizeof(MPADecodeContext),
2017  .init = decode_init,
2018  .decode = decode_frame,
2020  .capabilities = CODEC_CAP_PARSE_ONLY | CODEC_CAP_DR1,
2021 #else
2022  .capabilities = CODEC_CAP_DR1,
2023 #endif
2024  .flush = flush,
2025  .long_name = NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
2026 };
2027 #endif
2028 #if CONFIG_MP3_DECODER
2029 AVCodec ff_mp3_decoder = {
2030  .name = "mp3",
2031  .type = AVMEDIA_TYPE_AUDIO,
2032  .id = CODEC_ID_MP3,
2033  .priv_data_size = sizeof(MPADecodeContext),
2034  .init = decode_init,
2035  .decode = decode_frame,
2037  .capabilities = CODEC_CAP_PARSE_ONLY | CODEC_CAP_DR1,
2038 #else
2039  .capabilities = CODEC_CAP_DR1,
2040 #endif
2041  .flush = flush,
2042  .long_name = NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),
2043 };
2044 #endif
2045 #if CONFIG_MP3ADU_DECODER
2046 AVCodec ff_mp3adu_decoder = {
2047  .name = "mp3adu",
2048  .type = AVMEDIA_TYPE_AUDIO,
2049  .id = CODEC_ID_MP3ADU,
2050  .priv_data_size = sizeof(MPADecodeContext),
2051  .init = decode_init,
2052  .decode = decode_frame_adu,
2054  .capabilities = CODEC_CAP_PARSE_ONLY | CODEC_CAP_DR1,
2055 #else
2056  .capabilities = CODEC_CAP_DR1,
2057 #endif
2058  .flush = flush,
2059  .long_name = NULL_IF_CONFIG_SMALL("ADU (Application Data Unit) MP3 (MPEG audio layer 3)"),
2060 };
2061 #endif
2062 #if CONFIG_MP3ON4_DECODER
2063 AVCodec ff_mp3on4_decoder = {
2064  .name = "mp3on4",
2065  .type = AVMEDIA_TYPE_AUDIO,
2066  .id = CODEC_ID_MP3ON4,
2067  .priv_data_size = sizeof(MP3On4DecodeContext),
2068  .init = decode_init_mp3on4,
2069  .close = decode_close_mp3on4,
2070  .decode = decode_frame_mp3on4,
2071  .capabilities = CODEC_CAP_DR1,
2072  .flush = flush_mp3on4,
2073  .long_name = NULL_IF_CONFIG_SMALL("MP3onMP4"),
2074 };
2075 #endif
2076 #endif