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eac3dec.c
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1 /*
2  * E-AC-3 decoder
3  * Copyright (c) 2007 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com>
4  * Copyright (c) 2008 Justin Ruggles
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /*
24  * There are several features of E-AC-3 that this decoder does not yet support.
25  *
26  * Enhanced Coupling
27  * No known samples exist. If any ever surface, this feature should not be
28  * too difficult to implement.
29  *
30  * Reduced Sample Rates
31  * No known samples exist. The spec also does not give clear information
32  * on how this is to be implemented.
33  *
34  * Dependent Streams
35  * Only the independent stream is currently decoded. Any dependent
36  * streams are skipped. We have only come across two examples of this, and
37  * they are both just test streams, one for HD-DVD and the other for
38  * Blu-ray.
39  *
40  * Transient Pre-noise Processing
41  * This is side information which a decoder should use to reduce artifacts
42  * caused by transients. There are samples which are known to have this
43  * information, but this decoder currently ignores it.
44  */
45 
46 
47 #include "avcodec.h"
48 #include "internal.h"
49 #include "aac_ac3_parser.h"
50 #include "ac3.h"
51 #include "ac3dec.h"
52 #include "ac3dec_data.h"
53 #include "eac3_data.h"
54 
55 /** gain adaptive quantization mode */
56 typedef enum {
61 } EAC3GaqMode;
62 
63 #define EAC3_SR_CODE_REDUCED 3
64 
66 {
67  int bin, bnd, ch, i;
68  uint8_t wrapflag[SPX_MAX_BANDS]={1,0,}, num_copy_sections, copy_sizes[SPX_MAX_BANDS];
69  float rms_energy[SPX_MAX_BANDS];
70 
71  /* Set copy index mapping table. Set wrap flags to apply a notch filter at
72  wrap points later on. */
73  bin = s->spx_dst_start_freq;
74  num_copy_sections = 0;
75  for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
76  int copysize;
77  int bandsize = s->spx_band_sizes[bnd];
78  if (bin + bandsize > s->spx_src_start_freq) {
79  copy_sizes[num_copy_sections++] = bin - s->spx_dst_start_freq;
80  bin = s->spx_dst_start_freq;
81  wrapflag[bnd] = 1;
82  }
83  for (i = 0; i < bandsize; i += copysize) {
84  if (bin == s->spx_src_start_freq) {
85  copy_sizes[num_copy_sections++] = bin - s->spx_dst_start_freq;
86  bin = s->spx_dst_start_freq;
87  }
88  copysize = FFMIN(bandsize - i, s->spx_src_start_freq - bin);
89  bin += copysize;
90  }
91  }
92  copy_sizes[num_copy_sections++] = bin - s->spx_dst_start_freq;
93 
94  for (ch = 1; ch <= s->fbw_channels; ch++) {
95  if (!s->channel_uses_spx[ch])
96  continue;
97 
98  /* Copy coeffs from normal bands to extension bands */
99  bin = s->spx_src_start_freq;
100  for (i = 0; i < num_copy_sections; i++) {
101  memcpy(&s->transform_coeffs[ch][bin],
103  copy_sizes[i]*sizeof(INTFLOAT));
104  bin += copy_sizes[i];
105  }
106 
107  /* Calculate RMS energy for each SPX band. */
108  bin = s->spx_src_start_freq;
109  for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
110  int bandsize = s->spx_band_sizes[bnd];
111  float accum = 0.0f;
112  for (i = 0; i < bandsize; i++) {
113  float coeff = s->transform_coeffs[ch][bin++];
114  accum += coeff * coeff;
115  }
116  rms_energy[bnd] = sqrtf(accum / bandsize);
117  }
118 
119  /* Apply a notch filter at transitions between normal and extension
120  bands and at all wrap points. */
121  if (s->spx_atten_code[ch] >= 0) {
122  const float *atten_tab = ff_eac3_spx_atten_tab[s->spx_atten_code[ch]];
123  bin = s->spx_src_start_freq - 2;
124  for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
125  if (wrapflag[bnd]) {
126  INTFLOAT *coeffs = &s->transform_coeffs[ch][bin];
127  coeffs[0] *= atten_tab[0];
128  coeffs[1] *= atten_tab[1];
129  coeffs[2] *= atten_tab[2];
130  coeffs[3] *= atten_tab[1];
131  coeffs[4] *= atten_tab[0];
132  }
133  bin += s->spx_band_sizes[bnd];
134  }
135  }
136 
137  /* Apply noise-blended coefficient scaling based on previously
138  calculated RMS energy, blending factors, and SPX coordinates for
139  each band. */
140  bin = s->spx_src_start_freq;
141  for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
142  float nscale = s->spx_noise_blend[ch][bnd] * rms_energy[bnd] * (1.0f / INT32_MIN);
143  float sscale = s->spx_signal_blend[ch][bnd];
144 #if USE_FIXED
145  // spx_noise_blend and spx_signal_blend are both FP.23
146  nscale *= 1.0 / (1<<23);
147  sscale *= 1.0 / (1<<23);
148 #endif
149  for (i = 0; i < s->spx_band_sizes[bnd]; i++) {
150  float noise = nscale * (int32_t)av_lfg_get(&s->dith_state);
151  s->transform_coeffs[ch][bin] *= sscale;
152  s->transform_coeffs[ch][bin++] += noise;
153  }
154  }
155  }
156 }
157 
158 
159 /** lrint(M_SQRT2*cos(2*M_PI/12)*(1<<23)) */
160 #define COEFF_0 10273905LL
161 
162 /** lrint(M_SQRT2*cos(0*M_PI/12)*(1<<23)) = lrint(M_SQRT2*(1<<23)) */
163 #define COEFF_1 11863283LL
164 
165 /** lrint(M_SQRT2*cos(5*M_PI/12)*(1<<23)) */
166 #define COEFF_2 3070444LL
167 
168 /**
169  * Calculate 6-point IDCT of the pre-mantissas.
170  * All calculations are 24-bit fixed-point.
171  */
172 static void idct6(int pre_mant[6])
173 {
174  int tmp;
175  int even0, even1, even2, odd0, odd1, odd2;
176 
177  odd1 = pre_mant[1] - pre_mant[3] - pre_mant[5];
178 
179  even2 = ( pre_mant[2] * COEFF_0) >> 23;
180  tmp = ( pre_mant[4] * COEFF_1) >> 23;
181  odd0 = ((pre_mant[1] + pre_mant[5]) * COEFF_2) >> 23;
182 
183  even0 = pre_mant[0] + (tmp >> 1);
184  even1 = pre_mant[0] - tmp;
185 
186  tmp = even0;
187  even0 = tmp + even2;
188  even2 = tmp - even2;
189 
190  tmp = odd0;
191  odd0 = tmp + pre_mant[1] + pre_mant[3];
192  odd2 = tmp + pre_mant[5] - pre_mant[3];
193 
194  pre_mant[0] = even0 + odd0;
195  pre_mant[1] = even1 + odd1;
196  pre_mant[2] = even2 + odd2;
197  pre_mant[3] = even2 - odd2;
198  pre_mant[4] = even1 - odd1;
199  pre_mant[5] = even0 - odd0;
200 }
201 
203 {
204  int bin, blk, gs;
205  int end_bap, gaq_mode;
206  GetBitContext *gbc = &s->gbc;
207  int gaq_gain[AC3_MAX_COEFS];
208 
209  gaq_mode = get_bits(gbc, 2);
210  end_bap = (gaq_mode < 2) ? 12 : 17;
211 
212  /* if GAQ gain is used, decode gain codes for bins with hebap between
213  8 and end_bap */
214  gs = 0;
215  if (gaq_mode == EAC3_GAQ_12 || gaq_mode == EAC3_GAQ_14) {
216  /* read 1-bit GAQ gain codes */
217  for (bin = s->start_freq[ch]; bin < s->end_freq[ch]; bin++) {
218  if (s->bap[ch][bin] > 7 && s->bap[ch][bin] < end_bap)
219  gaq_gain[gs++] = get_bits1(gbc) << (gaq_mode-1);
220  }
221  } else if (gaq_mode == EAC3_GAQ_124) {
222  /* read 1.67-bit GAQ gain codes (3 codes in 5 bits) */
223  int gc = 2;
224  for (bin = s->start_freq[ch]; bin < s->end_freq[ch]; bin++) {
225  if (s->bap[ch][bin] > 7 && s->bap[ch][bin] < 17) {
226  if (gc++ == 2) {
227  int group_code = get_bits(gbc, 5);
228  if (group_code > 26) {
229  av_log(s->avctx, AV_LOG_WARNING, "GAQ gain group code out-of-range\n");
230  group_code = 26;
231  }
232  gaq_gain[gs++] = ff_ac3_ungroup_3_in_5_bits_tab[group_code][0];
233  gaq_gain[gs++] = ff_ac3_ungroup_3_in_5_bits_tab[group_code][1];
234  gaq_gain[gs++] = ff_ac3_ungroup_3_in_5_bits_tab[group_code][2];
235  gc = 0;
236  }
237  }
238  }
239  }
240 
241  gs=0;
242  for (bin = s->start_freq[ch]; bin < s->end_freq[ch]; bin++) {
243  int hebap = s->bap[ch][bin];
244  int bits = ff_eac3_bits_vs_hebap[hebap];
245  if (!hebap) {
246  /* zero-mantissa dithering */
247  for (blk = 0; blk < 6; blk++) {
248  s->pre_mantissa[ch][bin][blk] = (av_lfg_get(&s->dith_state) & 0x7FFFFF) - 0x400000;
249  }
250  } else if (hebap < 8) {
251  /* Vector Quantization */
252  int v = get_bits(gbc, bits);
253  for (blk = 0; blk < 6; blk++) {
254  s->pre_mantissa[ch][bin][blk] = ff_eac3_mantissa_vq[hebap][v][blk] * (1 << 8);
255  }
256  } else {
257  /* Gain Adaptive Quantization */
258  int gbits, log_gain;
259  if (gaq_mode != EAC3_GAQ_NO && hebap < end_bap) {
260  log_gain = gaq_gain[gs++];
261  } else {
262  log_gain = 0;
263  }
264  gbits = bits - log_gain;
265 
266  for (blk = 0; blk < 6; blk++) {
267  int mant = get_sbits(gbc, gbits);
268  if (log_gain && mant == -(1 << (gbits-1))) {
269  /* large mantissa */
270  int b;
271  int mbits = bits - (2 - log_gain);
272  mant = get_sbits(gbc, mbits);
273  mant = ((unsigned)mant) << (23 - (mbits - 1));
274  /* remap mantissa value to correct for asymmetric quantization */
275  if (mant >= 0)
276  b = 1 << (23 - log_gain);
277  else
278  b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1] * (1 << 8);
279  mant += ((ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] * (int64_t)mant) >> 15) + b;
280  } else {
281  /* small mantissa, no GAQ, or Gk=1 */
282  mant *= (1 << 24 - bits);
283  if (!log_gain) {
284  /* remap mantissa value for no GAQ or Gk=1 */
285  mant += (ff_eac3_gaq_remap_1[hebap-8] * (int64_t)mant) >> 15;
286  }
287  }
288  s->pre_mantissa[ch][bin][blk] = mant;
289  }
290  }
291  idct6(s->pre_mantissa[ch][bin]);
292  }
293 }
294 
296 {
297  int i, blk, ch;
298  int ac3_exponent_strategy, parse_aht_info, parse_spx_atten_data;
299  int parse_transient_proc_info;
300  int num_cpl_blocks;
301  GetBitContext *gbc = &s->gbc;
302 
303  /* An E-AC-3 stream can have multiple independent streams which the
304  application can select from. each independent stream can also contain
305  dependent streams which are used to add or replace channels. */
307  if (!s->eac3_frame_dependent_found) {
309  avpriv_request_sample(s->avctx, "Dependent substream decoding");
310  }
312  } else if (s->frame_type == EAC3_FRAME_TYPE_RESERVED) {
313  av_log(s->avctx, AV_LOG_ERROR, "Reserved frame type\n");
315  }
316 
317  /* The substream id indicates which substream this frame belongs to. each
318  independent stream has its own substream id, and the dependent streams
319  associated to an independent stream have matching substream id's. */
320  if (s->substreamid) {
321  /* only decode substream with id=0. skip any additional substreams. */
322  if (!s->eac3_subsbtreamid_found) {
324  avpriv_request_sample(s->avctx, "Additional substreams");
325  }
327  }
328 
330  /* The E-AC-3 specification does not tell how to handle reduced sample
331  rates in bit allocation. The best assumption would be that it is
332  handled like AC-3 DolbyNet, but we cannot be sure until we have a
333  sample which utilizes this feature. */
334  avpriv_request_sample(s->avctx, "Reduced sampling rate");
335  return AVERROR_PATCHWELCOME;
336  }
337  skip_bits(gbc, 5); // skip bitstream id
338 
339  /* volume control params */
340  for (i = 0; i < (s->channel_mode ? 1 : 2); i++) {
341  s->dialog_normalization[i] = -get_bits(gbc, 5);
342  if (s->dialog_normalization[i] == 0) {
343  s->dialog_normalization[i] = -31;
344  }
345  if (s->target_level != 0) {
346  s->level_gain[i] = powf(2.0f,
347  (float)(s->target_level - s->dialog_normalization[i])/6.0f);
348  }
349  s->compression_exists[i] = get_bits1(gbc);
350  if (s->compression_exists[i]) {
352  }
353  }
354 
355  /* dependent stream channel map */
357  if (get_bits1(gbc)) {
358  skip_bits(gbc, 16); // skip custom channel map
359  }
360  }
361 
362  /* mixing metadata */
363  if (get_bits1(gbc)) {
364  /* center and surround mix levels */
365  if (s->channel_mode > AC3_CHMODE_STEREO) {
366  s->preferred_downmix = get_bits(gbc, 2);
367  if (s->channel_mode & 1) {
368  /* if three front channels exist */
369  s->center_mix_level_ltrt = get_bits(gbc, 3);
370  s->center_mix_level = get_bits(gbc, 3);
371  }
372  if (s->channel_mode & 4) {
373  /* if a surround channel exists */
374  s->surround_mix_level_ltrt = av_clip(get_bits(gbc, 3), 3, 7);
375  s->surround_mix_level = av_clip(get_bits(gbc, 3), 3, 7);
376  }
377  }
378 
379  /* lfe mix level */
380  if (s->lfe_on && (s->lfe_mix_level_exists = get_bits1(gbc))) {
381  s->lfe_mix_level = get_bits(gbc, 5);
382  }
383 
384  /* info for mixing with other streams and substreams */
386  for (i = 0; i < (s->channel_mode ? 1 : 2); i++) {
387  // TODO: apply program scale factor
388  if (get_bits1(gbc)) {
389  skip_bits(gbc, 6); // skip program scale factor
390  }
391  }
392  if (get_bits1(gbc)) {
393  skip_bits(gbc, 6); // skip external program scale factor
394  }
395  /* skip mixing parameter data */
396  switch(get_bits(gbc, 2)) {
397  case 1: skip_bits(gbc, 5); break;
398  case 2: skip_bits(gbc, 12); break;
399  case 3: {
400  int mix_data_size = (get_bits(gbc, 5) + 2) << 3;
401  skip_bits_long(gbc, mix_data_size);
402  break;
403  }
404  }
405  /* skip pan information for mono or dual mono source */
406  if (s->channel_mode < AC3_CHMODE_STEREO) {
407  for (i = 0; i < (s->channel_mode ? 1 : 2); i++) {
408  if (get_bits1(gbc)) {
409  /* note: this is not in the ATSC A/52B specification
410  reference: ETSI TS 102 366 V1.1.1
411  section: E.1.3.1.25 */
412  skip_bits(gbc, 8); // skip pan mean direction index
413  skip_bits(gbc, 6); // skip reserved paninfo bits
414  }
415  }
416  }
417  /* skip mixing configuration information */
418  if (get_bits1(gbc)) {
419  for (blk = 0; blk < s->num_blocks; blk++) {
420  if (s->num_blocks == 1 || get_bits1(gbc)) {
421  skip_bits(gbc, 5);
422  }
423  }
424  }
425  }
426  }
427 
428  /* informational metadata */
429  if (get_bits1(gbc)) {
430  s->bitstream_mode = get_bits(gbc, 3);
431  skip_bits(gbc, 2); // skip copyright bit and original bitstream bit
432  if (s->channel_mode == AC3_CHMODE_STEREO) {
433  s->dolby_surround_mode = get_bits(gbc, 2);
434  s->dolby_headphone_mode = get_bits(gbc, 2);
435  }
436  if (s->channel_mode >= AC3_CHMODE_2F2R) {
437  s->dolby_surround_ex_mode = get_bits(gbc, 2);
438  }
439  for (i = 0; i < (s->channel_mode ? 1 : 2); i++) {
440  if (get_bits1(gbc)) {
441  skip_bits(gbc, 8); // skip mix level, room type, and A/D converter type
442  }
443  }
445  skip_bits1(gbc); // skip source sample rate code
446  }
447  }
448 
449  /* converter synchronization flag
450  If frames are less than six blocks, this bit should be turned on
451  once every 6 blocks to indicate the start of a frame set.
452  reference: RFC 4598, Section 2.1.3 Frame Sets */
453  if (s->frame_type == EAC3_FRAME_TYPE_INDEPENDENT && s->num_blocks != 6) {
454  skip_bits1(gbc); // skip converter synchronization flag
455  }
456 
457  /* original frame size code if this stream was converted from AC-3 */
459  (s->num_blocks == 6 || get_bits1(gbc))) {
460  skip_bits(gbc, 6); // skip frame size code
461  }
462 
463  /* additional bitstream info */
464  if (get_bits1(gbc)) {
465  int addbsil = get_bits(gbc, 6);
466  for (i = 0; i < addbsil + 1; i++) {
467  skip_bits(gbc, 8); // skip additional bit stream info
468  }
469  }
470 
471  /* audio frame syntax flags, strategy data, and per-frame data */
472 
473  if (s->num_blocks == 6) {
474  ac3_exponent_strategy = get_bits1(gbc);
475  parse_aht_info = get_bits1(gbc);
476  } else {
477  /* less than 6 blocks, so use AC-3-style exponent strategy syntax, and
478  do not use AHT */
479  ac3_exponent_strategy = 1;
480  parse_aht_info = 0;
481  }
482 
483  s->snr_offset_strategy = get_bits(gbc, 2);
484  parse_transient_proc_info = get_bits1(gbc);
485 
486  s->block_switch_syntax = get_bits1(gbc);
487  if (!s->block_switch_syntax)
488  memset(s->block_switch, 0, sizeof(s->block_switch));
489 
490  s->dither_flag_syntax = get_bits1(gbc);
491  if (!s->dither_flag_syntax) {
492  for (ch = 1; ch <= s->fbw_channels; ch++)
493  s->dither_flag[ch] = 1;
494  }
495  s->dither_flag[CPL_CH] = s->dither_flag[s->lfe_ch] = 0;
496 
498  if (!s->bit_allocation_syntax) {
499  /* set default bit allocation parameters */
505  }
506 
507  s->fast_gain_syntax = get_bits1(gbc);
508  s->dba_syntax = get_bits1(gbc);
509  s->skip_syntax = get_bits1(gbc);
510  parse_spx_atten_data = get_bits1(gbc);
511 
512  /* coupling strategy occurrence and coupling use per block */
513  num_cpl_blocks = 0;
514  if (s->channel_mode > 1) {
515  for (blk = 0; blk < s->num_blocks; blk++) {
516  s->cpl_strategy_exists[blk] = (!blk || get_bits1(gbc));
517  if (s->cpl_strategy_exists[blk]) {
518  s->cpl_in_use[blk] = get_bits1(gbc);
519  } else {
520  s->cpl_in_use[blk] = s->cpl_in_use[blk-1];
521  }
522  num_cpl_blocks += s->cpl_in_use[blk];
523  }
524  } else {
525  memset(s->cpl_in_use, 0, sizeof(s->cpl_in_use));
526  }
527 
528  /* exponent strategy data */
529  if (ac3_exponent_strategy) {
530  /* AC-3-style exponent strategy syntax */
531  for (blk = 0; blk < s->num_blocks; blk++) {
532  for (ch = !s->cpl_in_use[blk]; ch <= s->fbw_channels; ch++) {
533  s->exp_strategy[blk][ch] = get_bits(gbc, 2);
534  }
535  }
536  } else {
537  /* LUT-based exponent strategy syntax */
538  for (ch = !((s->channel_mode > 1) && num_cpl_blocks); ch <= s->fbw_channels; ch++) {
539  int frmchexpstr = get_bits(gbc, 5);
540  for (blk = 0; blk < 6; blk++) {
541  s->exp_strategy[blk][ch] = ff_eac3_frm_expstr[frmchexpstr][blk];
542  }
543  }
544  }
545  /* LFE exponent strategy */
546  if (s->lfe_on) {
547  for (blk = 0; blk < s->num_blocks; blk++) {
548  s->exp_strategy[blk][s->lfe_ch] = get_bits1(gbc);
549  }
550  }
551  /* original exponent strategies if this stream was converted from AC-3 */
553  (s->num_blocks == 6 || get_bits1(gbc))) {
554  skip_bits(gbc, 5 * s->fbw_channels); // skip converter channel exponent strategy
555  }
556 
557  /* determine which channels use AHT */
558  if (parse_aht_info) {
559  /* For AHT to be used, all non-zero blocks must reuse exponents from
560  the first block. Furthermore, for AHT to be used in the coupling
561  channel, all blocks must use coupling and use the same coupling
562  strategy. */
563  s->channel_uses_aht[CPL_CH]=0;
564  for (ch = (num_cpl_blocks != 6); ch <= s->channels; ch++) {
565  int use_aht = 1;
566  for (blk = 1; blk < 6; blk++) {
567  if ((s->exp_strategy[blk][ch] != EXP_REUSE) ||
568  (!ch && s->cpl_strategy_exists[blk])) {
569  use_aht = 0;
570  break;
571  }
572  }
573  s->channel_uses_aht[ch] = use_aht && get_bits1(gbc);
574  }
575  } else {
576  memset(s->channel_uses_aht, 0, sizeof(s->channel_uses_aht));
577  }
578 
579  /* per-frame SNR offset */
580  if (!s->snr_offset_strategy) {
581  int csnroffst = (get_bits(gbc, 6) - 15) << 4;
582  int snroffst = (csnroffst + get_bits(gbc, 4)) << 2;
583  for (ch = 0; ch <= s->channels; ch++)
584  s->snr_offset[ch] = snroffst;
585  }
586 
587  /* transient pre-noise processing data */
588  if (parse_transient_proc_info) {
589  for (ch = 1; ch <= s->fbw_channels; ch++) {
590  if (get_bits1(gbc)) { // channel in transient processing
591  skip_bits(gbc, 10); // skip transient processing location
592  skip_bits(gbc, 8); // skip transient processing length
593  }
594  }
595  }
596 
597  /* spectral extension attenuation data */
598  for (ch = 1; ch <= s->fbw_channels; ch++) {
599  if (parse_spx_atten_data && get_bits1(gbc)) {
600  s->spx_atten_code[ch] = get_bits(gbc, 5);
601  } else {
602  s->spx_atten_code[ch] = -1;
603  }
604  }
605 
606  /* block start information */
607  if (s->num_blocks > 1 && get_bits1(gbc)) {
608  /* reference: Section E2.3.2.27
609  nblkstrtbits = (numblks - 1) * (4 + ceiling(log2(words_per_frame)))
610  The spec does not say what this data is or what it's used for.
611  It is likely the offset of each block within the frame. */
612  int block_start_bits = (s->num_blocks-1) * (4 + av_log2(s->frame_size-2));
613  skip_bits_long(gbc, block_start_bits);
614  avpriv_request_sample(s->avctx, "Block start info");
615  }
616 
617  /* syntax state initialization */
618  for (ch = 1; ch <= s->fbw_channels; ch++) {
619  s->first_spx_coords[ch] = 1;
620  s->first_cpl_coords[ch] = 1;
621  }
622  s->first_cpl_leak = 1;
623 
624  return 0;
625 }
EAC3GaqMode
gain adaptive quantization mode
Definition: eac3dec.c:56
const char * s
Definition: avisynth_c.h:768
static int noise(AVBSFContext *ctx, AVPacket *out)
Definition: noise_bsf.c:38
const uint8_t ff_ac3_slow_decay_tab[4]
Definition: ac3tab.c:280
int dither_flag[AC3_MAX_CHANNELS]
dither flags (dithflg)
Definition: ac3dec.h:214
const float ff_eac3_spx_atten_tab[32][3]
Table E.25: Spectral Extension Attenuation Table ff_eac3_spx_atten_tab[code][bin]=pow(2.0,(bin+1)*(code+1)/-15.0);.
Definition: eac3_data.c:1101
int preferred_downmix
Preferred 2-channel downmix mode (dmixmod)
Definition: ac3dec.h:91
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:261
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
const uint8_t ff_ac3_ungroup_3_in_5_bits_tab[32][3]
Table used to ungroup 3 values stored in 5 bits.
Definition: ac3dec_data.c:35
static int ff_eac3_parse_header(AC3DecodeContext *s)
Definition: eac3dec.c:295
static void skip_bits_long(GetBitContext *s, int n)
Definition: get_bits.h:204
#define AC3_MAX_COEFS
Definition: ac3.h:34
const char * b
Definition: vf_curves.c:113
int channels
number of total channels
Definition: ac3dec.h:162
int av_log2(unsigned v)
Definition: intmath.c:26
#define EXP_REUSE
Definition: ac3.h:47
int exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS]
exponent strategies (expstr)
Definition: ac3dec.h:194
int lfe_on
lfe channel in use
Definition: ac3dec.h:86
const uint16_t ff_ac3_slow_gain_tab[4]
Definition: ac3tab.c:288
int block_switch[AC3_MAX_CHANNELS]
block switch flags (blksw)
Definition: ac3dec.h:219
#define blk(i)
Definition: sha.c:185
int dba_syntax
delta bit allocation syntax enabled (dbaflde)
Definition: ac3dec.h:120
int dialog_normalization[2]
dialog level in dBFS (dialnorm)
Definition: ac3dec.h:87
int spx_src_start_freq
spx start frequency bin
Definition: ac3dec.h:143
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:246
int lfe_mix_level_exists
indicates if lfemixlevcod is specified (lfemixlevcode)
Definition: ac3dec.h:96
float INTFLOAT
Definition: aac_defines.h:86
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
#define COEFF_0
lrint(M_SQRT2*cos(2*M_PI/12)*(1<<23))
Definition: eac3dec.c:160
uint8_t
int first_cpl_coords[AC3_MAX_CHANNELS]
first coupling coordinates states (firstcplcos)
Definition: ac3dec.h:134
INTFLOAT spx_noise_blend[AC3_MAX_CHANNELS][SPX_MAX_BANDS]
spx noise blending factor (nblendfact)
Definition: ac3dec.h:151
int bit_allocation_syntax
bit allocation model syntax enabled (bamode)
Definition: ac3dec.h:118
#define av_log(a,...)
Common code between the AC-3 and E-AC-3 decoders.
static void ff_eac3_decode_transform_coeffs_aht_ch(AC3DecodeContext *s, int ch)
Definition: eac3dec.c:202
int substreamid
substream identification
Definition: ac3dec.h:78
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
const uint8_t ff_ac3_fast_decay_tab[4]
Definition: ac3tab.c:284
int lfe_ch
index of LFE channel
Definition: ac3dec.h:163
uint8_t first_spx_coords[AC3_MAX_CHANNELS]
first spx coordinates states (firstspxcos)
Definition: ac3dec.h:150
AC3BitAllocParameters bit_alloc_params
bit allocation parameters
Definition: ac3dec.h:198
int dolby_surround_mode
dolby surround mode (dsurmod)
Definition: ac3dec.h:101
GetBitContext gbc
bitstream reader
Definition: ac3dec.h:73
int eac3_subsbtreamid_found
bitstream has E-AC-3 additional substream(s)
Definition: ac3dec.h:100
int dolby_headphone_mode
dolby headphone mode (dheadphonmod)
Definition: ac3dec.h:103
#define COEFF_2
lrint(M_SQRT2*cos(5*M_PI/12)*(1<<23))
Definition: eac3dec.c:166
int compression_exists[2]
compression field is valid for frame (compre)
Definition: ac3dec.h:88
INTFLOAT transform_coeffs[AC3_MAX_CHANNELS][AC3_MAX_COEFS]
transform coefficients
Definition: ac3dec.h:241
#define EAC3_SR_CODE_REDUCED
Definition: eac3dec.c:63
int block_switch_syntax
block switch syntax enabled (blkswe)
Definition: ac3dec.h:116
float level_gain[2]
Definition: ac3dec.h:112
int fast_gain_syntax
fast gain codes enabled (frmfgaincode)
Definition: ac3dec.h:119
uint8_t channel_uses_spx[AC3_MAX_CHANNELS]
channel uses spectral extension (chinspx)
Definition: ac3dec.h:141
#define powf(x, y)
Definition: libm.h:50
static void idct6(int pre_mant[6])
Calculate 6-point IDCT of the pre-mantissas.
Definition: eac3dec.c:172
#define AC3_HEAVY_RANGE(x)
Definition: ac3.h:90
int surround_mix_level_ltrt
Surround mix level index for Lt/Rt (ltrtsurmixlev)
Definition: ac3dec.h:95
#define FFMIN(a, b)
Definition: common.h:96
int dither_flag_syntax
dither flag syntax enabled (dithflage)
Definition: ac3dec.h:117
INTFLOAT heavy_dynamic_range[2]
heavy dynamic range compression
Definition: ac3dec.h:174
int32_t
const int16_t ff_eac3_gaq_remap_1[12]
Table E3.6, Gk=1 No gain (Gk=1) inverse quantization, remapping scale factors ff_eac3_gaq_remap[hebap...
Definition: eac3_data.c:40
const int16_t ff_eac3_gaq_remap_2_4_a[9][2]
Table E3.6, Gk=2 & Gk=4, A Large mantissa inverse quantization, remapping scale factors ff_eac3_gaq_r...
Definition: eac3_data.c:49
#define COEFF_1
lrint(M_SQRT2*cos(0*M_PI/12)*(1<<23)) = lrint(M_SQRT2*(1<<23))
Definition: eac3dec.c:163
AVCodecContext * avctx
parent context
Definition: ac3dec.h:72
const uint8_t ff_eac3_bits_vs_hebap[20]
Definition: eac3_data.c:30
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
int fbw_channels
number of full-bandwidth channels
Definition: ac3dec.h:161
int8_t spx_atten_code[AC3_MAX_CHANNELS]
spx attenuation code (spxattencod)
Definition: ac3dec.h:142
uint8_t bap[AC3_MAX_CHANNELS][AC3_MAX_COEFS]
bit allocation pointers
Definition: ac3dec.h:202
#define CPL_CH
coupling channel index
Definition: ac3.h:32
Libavcodec external API header.
const int16_t ff_eac3_gaq_remap_2_4_b[9][2]
Table E3.6, Gk=2 & Gk=4, B Large mantissa inverse quantization, negative mantissa remapping offsets f...
Definition: eac3_data.c:66
static void ff_eac3_apply_spectral_extension(AC3DecodeContext *s)
Definition: eac3dec.c:65
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:47
int num_spx_bands
number of spx bands (nspxbnds)
Definition: ac3dec.h:147
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:313
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:338
INTFLOAT spx_signal_blend[AC3_MAX_CHANNELS][SPX_MAX_BANDS]
spx signal blending factor (sblendfact)
Definition: ac3dec.h:152
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:306
int bitstream_mode
bitstream mode (bsmod)
Definition: ac3dec.h:84
int center_mix_level_ltrt
Center mix level index for Lt/Rt (ltrtcmixlev)
Definition: ac3dec.h:93
int frame_type
frame type (strmtyp)
Definition: ac3dec.h:77
int channel_uses_aht[AC3_MAX_CHANNELS]
channel AHT in use (chahtinu)
Definition: ac3dec.h:156
const int16_t ff_ac3_floor_tab[8]
Definition: ac3tab.c:296
int cpl_in_use[AC3_MAX_BLOCKS]
coupling in use (cplinu)
Definition: ac3dec.h:125
int first_cpl_leak
first coupling leak state (firstcplleak)
Definition: ac3dec.h:199
int surround_mix_level
Surround mix level index.
Definition: ac3dec.h:94
int snr_offset[AC3_MAX_CHANNELS]
signal-to-noise ratio offsets (snroffst)
Definition: ac3dec.h:200
common internal api header.
const uint8_t ff_eac3_frm_expstr[32][6]
Table E2.14 Frame Exponent Strategy Combinations.
Definition: eac3_data.c:1062
int num_blocks
number of audio blocks
Definition: ac3dec.h:82
#define SPX_MAX_BANDS
Definition: ac3dec.h:65
int target_level
target level in dBFS
Definition: ac3dec.h:111
int pre_mantissa[AC3_MAX_CHANNELS][AC3_MAX_COEFS][AC3_MAX_BLOCKS]
pre-IDCT mantissas
Definition: ac3dec.h:157
uint8_t spx_band_sizes[SPX_MAX_BANDS]
number of bins in each spx band
Definition: ac3dec.h:149
int lfe_mix_level
LFE mix level index (lfemixlevcod)
Definition: ac3dec.h:97
int snr_offset_strategy
SNR offset strategy (snroffststr)
Definition: ac3dec.h:115
static const int16_t coeffs[]
int start_freq[AC3_MAX_CHANNELS]
start frequency bin (strtmant)
Definition: ac3dec.h:178
int center_mix_level
Center mix level index.
Definition: ac3dec.h:92
static const double coeff[2][5]
Definition: vf_owdenoise.c:72
int frame_size
current frame size, in bytes
Definition: ac3dec.h:79
const int16_t(*const [8] ff_eac3_mantissa_vq)[6]
Definition: eac3_data.c:1048
int dolby_surround_ex_mode
dolby surround ex mode (dsurexmod)
Definition: ac3dec.h:102
AVLFG dith_state
for dither generation
Definition: ac3dec.h:215
int cpl_strategy_exists[AC3_MAX_BLOCKS]
coupling strategy exists (cplstre)
Definition: ac3dec.h:126
const uint16_t ff_ac3_db_per_bit_tab[4]
Definition: ac3tab.c:292
int eac3_frame_dependent_found
bitstream has E-AC-3 dependent frame(s)
Definition: ac3dec.h:99
Common code between the AC-3 encoder and decoder.
int channel_mode
channel mode (acmod)
Definition: ac3dec.h:85
int spx_dst_start_freq
spx starting frequency bin for copying (copystartmant) the copy region ends at the start of the spx r...
Definition: ac3dec.h:145
int skip_syntax
skip field syntax enabled (skipflde)
Definition: ac3dec.h:121
uint8_t pi<< 24) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_U8,(uint64_t)((*(constuint8_t *) pi-0x80U))<< 56) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_S16,(uint64_t)(*(constint16_t *) pi)<< 48) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_S32,(uint64_t)(*(constint32_t *) pi)<< 32) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S64,(*(constint64_t *) pi >>56)+0x80) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S64,*(constint64_t *) pi *(1.0f/(INT64_C(1)<< 63))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S64,*(constint64_t *) pi *(1.0/(INT64_C(1)<< 63))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_FLT, llrintf(*(constfloat *) pi *(INT64_C(1)<< 63))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31)))) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_DBL, llrint(*(constdouble *) pi *(INT64_C(1)<< 63)))#defineFMT_PAIR_FUNC(out, in) staticconv_func_type *constfmt_pair_to_conv_functions[AV_SAMPLE_FMT_NB *AV_SAMPLE_FMT_NB]={FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_S64),};staticvoidcpy1(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, len);}staticvoidcpy2(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, 2 *len);}staticvoidcpy4(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, 4 *len);}staticvoidcpy8(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, 8 *len);}AudioConvert *swri_audio_convert_alloc(enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, constint *ch_map, intflags){AudioConvert *ctx;conv_func_type *f=fmt_pair_to_conv_functions[av_get_packed_sample_fmt(out_fmt)+AV_SAMPLE_FMT_NB *av_get_packed_sample_fmt(in_fmt)];if(!f) returnNULL;ctx=av_mallocz(sizeof(*ctx));if(!ctx) returnNULL;if(channels==1){in_fmt=av_get_planar_sample_fmt(in_fmt);out_fmt=av_get_planar_sample_fmt(out_fmt);}ctx->channels=channels;ctx->conv_f=f;ctx->ch_map=ch_map;if(in_fmt==AV_SAMPLE_FMT_U8||in_fmt==AV_SAMPLE_FMT_U8P) memset(ctx->silence, 0x80, sizeof(ctx->silence));if(out_fmt==in_fmt &&!ch_map){switch(av_get_bytes_per_sample(in_fmt)){case1:ctx->simd_f=cpy1;break;case2:ctx->simd_f=cpy2;break;case4:ctx->simd_f=cpy4;break;case8:ctx->simd_f=cpy8;break;}}if(HAVE_X86ASM &&1) swri_audio_convert_init_x86(ctx, out_fmt, in_fmt, channels);if(ARCH_ARM) swri_audio_convert_init_arm(ctx, out_fmt, in_fmt, channels);if(ARCH_AARCH64) swri_audio_convert_init_aarch64(ctx, out_fmt, in_fmt, channels);returnctx;}voidswri_audio_convert_free(AudioConvert **ctx){av_freep(ctx);}intswri_audio_convert(AudioConvert *ctx, AudioData *out, AudioData *in, intlen){intch;intoff=0;constintos=(out->planar?1:out->ch_count)*out->bps;unsignedmisaligned=0;av_assert0(ctx->channels==out->ch_count);if(ctx->in_simd_align_mask){intplanes=in->planar?in->ch_count:1;unsignedm=0;for(ch=0;ch< planes;ch++) m|=(intptr_t) in->ch[ch];misaligned|=m &ctx->in_simd_align_mask;}if(ctx->out_simd_align_mask){intplanes=out->planar?out->ch_count:1;unsignedm=0;for(ch=0;ch< planes;ch++) m|=(intptr_t) out->ch[ch];misaligned|=m &ctx->out_simd_align_mask;}if(ctx->simd_f &&!ctx->ch_map &&!misaligned){off=len &~15;av_assert1(off >=0);av_assert1(off<=len);av_assert2(ctx->channels==SWR_CH_MAX||!in->ch[ctx->channels]);if(off >0){if(out->planar==in->planar){intplanes=out->planar?out->ch_count:1;for(ch=0;ch< planes;ch++){ctx->simd_f(out-> ch ch
Definition: audioconvert.c:56
static uint8_t tmp[11]
Definition: aes_ctr.c:26