Libav
ac3enc.c
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1 /*
2  * The simplest AC-3 encoder
3  * Copyright (c) 2000 Fabrice Bellard
4  * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
5  * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
6  *
7  * This file is part of Libav.
8  *
9  * Libav is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * Libav is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with Libav; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
29 #include <stdint.h>
30 
31 #include "libavutil/attributes.h"
32 #include "libavutil/avassert.h"
33 #include "libavutil/avstring.h"
35 #include "libavutil/crc.h"
36 #include "libavutil/internal.h"
37 #include "libavutil/opt.h"
38 #include "avcodec.h"
39 #include "put_bits.h"
40 #include "ac3dsp.h"
41 #include "ac3.h"
42 #include "fft.h"
43 #include "ac3enc.h"
44 #include "eac3enc.h"
45 
46 typedef struct AC3Mant {
49 } AC3Mant;
50 
51 #define CMIXLEV_NUM_OPTIONS 3
52 static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
54 };
55 
56 #define SURMIXLEV_NUM_OPTIONS 3
59 };
60 
61 #define EXTMIXLEV_NUM_OPTIONS 8
65 };
66 
67 
72 static uint8_t exponent_group_tab[2][3][256];
73 
74 
78 const uint64_t ff_ac3_channel_layouts[19] = {
89  (AV_CH_LAYOUT_STEREO | AV_CH_LOW_FREQUENCY),
90  (AV_CH_LAYOUT_2_1 | AV_CH_LOW_FREQUENCY),
91  (AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY),
92  (AV_CH_LAYOUT_2_2 | AV_CH_LOW_FREQUENCY),
93  (AV_CH_LAYOUT_QUAD | AV_CH_LOW_FREQUENCY),
94  (AV_CH_LAYOUT_4POINT0 | AV_CH_LOW_FREQUENCY),
97  0
98 };
99 
100 
106 static const uint8_t ac3_bandwidth_tab[5][3][19] = {
107 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
108 
109  { { 0, 0, 0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
110  { 0, 0, 0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
111  { 0, 0, 0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
112 
113  { { 0, 0, 0, 0, 0, 0, 0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
114  { 0, 0, 0, 0, 0, 0, 4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
115  { 0, 0, 0, 0, 0, 0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
116 
117  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
118  { 0, 0, 0, 0, 0, 0, 0, 0, 4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
119  { 0, 0, 0, 0, 0, 0, 0, 0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
120 
121  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
122  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
123  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
124 
125  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 20, 32, 40, 48, 48, 48, 48 },
126  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 36, 44, 56, 56, 56, 56 },
127  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28, 44, 60, 60, 60, 60, 60, 60 } }
128 };
129 
130 
139 static const int8_t ac3_coupling_start_tab[6][3][19] = {
140 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
141 
142  // 2/0
143  { { 0, 0, 0, 0, 0, 0, 0, 1, 1, 7, 8, 11, 12, -1, -1, -1, -1, -1, -1 },
144  { 0, 0, 0, 0, 0, 0, 1, 3, 5, 7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
145  { 0, 0, 0, 0, 1, 2, 2, 9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
146 
147  // 3/0
148  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
149  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
150  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
151 
152  // 2/1 - untested
153  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
154  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
155  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
156 
157  // 3/1
158  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
159  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
160  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
161 
162  // 2/2 - untested
163  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
164  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
165  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
166 
167  // 3/2
168  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
169  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
170  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
171 };
172 
173 
181 {
182  while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
183  s->bits_written -= s->bit_rate;
184  s->samples_written -= s->sample_rate;
185  }
186  s->frame_size = s->frame_size_min +
187  2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
188  s->bits_written += s->frame_size * 8;
190 }
191 
192 
199 {
200  int blk, ch;
201  int got_cpl_snr;
202  int num_cpl_blocks;
203 
204  /* set coupling use flags for each block/channel */
205  /* TODO: turn coupling on/off and adjust start band based on bit usage */
206  for (blk = 0; blk < s->num_blocks; blk++) {
207  AC3Block *block = &s->blocks[blk];
208  for (ch = 1; ch <= s->fbw_channels; ch++)
209  block->channel_in_cpl[ch] = s->cpl_on;
210  }
211 
212  /* enable coupling for each block if at least 2 channels have coupling
213  enabled for that block */
214  got_cpl_snr = 0;
215  num_cpl_blocks = 0;
216  for (blk = 0; blk < s->num_blocks; blk++) {
217  AC3Block *block = &s->blocks[blk];
218  block->num_cpl_channels = 0;
219  for (ch = 1; ch <= s->fbw_channels; ch++)
220  block->num_cpl_channels += block->channel_in_cpl[ch];
221  block->cpl_in_use = block->num_cpl_channels > 1;
222  num_cpl_blocks += block->cpl_in_use;
223  if (!block->cpl_in_use) {
224  block->num_cpl_channels = 0;
225  for (ch = 1; ch <= s->fbw_channels; ch++)
226  block->channel_in_cpl[ch] = 0;
227  }
228 
229  block->new_cpl_strategy = !blk;
230  if (blk) {
231  for (ch = 1; ch <= s->fbw_channels; ch++) {
232  if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
233  block->new_cpl_strategy = 1;
234  break;
235  }
236  }
237  }
238  block->new_cpl_leak = block->new_cpl_strategy;
239 
240  if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
241  block->new_snr_offsets = 1;
242  if (block->cpl_in_use)
243  got_cpl_snr = 1;
244  } else {
245  block->new_snr_offsets = 0;
246  }
247  }
248  if (!num_cpl_blocks)
249  s->cpl_on = 0;
250 
251  /* set bandwidth for each channel */
252  for (blk = 0; blk < s->num_blocks; blk++) {
253  AC3Block *block = &s->blocks[blk];
254  for (ch = 1; ch <= s->fbw_channels; ch++) {
255  if (block->channel_in_cpl[ch])
256  block->end_freq[ch] = s->start_freq[CPL_CH];
257  else
258  block->end_freq[ch] = s->bandwidth_code * 3 + 73;
259  }
260  }
261 }
262 
263 
270 {
271  int nb_coefs;
272  int blk, bnd, i;
273  int start, end;
274  uint8_t *flags;
275 
276  if (!s->rematrixing_enabled)
277  return;
278 
279  for (blk = 0; blk < s->num_blocks; blk++) {
280  AC3Block *block = &s->blocks[blk];
281  if (block->new_rematrixing_strategy)
282  flags = block->rematrixing_flags;
283  nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
284  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
285  if (flags[bnd]) {
286  start = ff_ac3_rematrix_band_tab[bnd];
287  end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
288  for (i = start; i < end; i++) {
289  int32_t lt = block->fixed_coef[1][i];
290  int32_t rt = block->fixed_coef[2][i];
291  block->fixed_coef[1][i] = (lt + rt) >> 1;
292  block->fixed_coef[2][i] = (lt - rt) >> 1;
293  }
294  }
295  }
296  }
297 }
298 
299 
300 /*
301  * Initialize exponent tables.
302  */
304 {
305  int expstr, i, grpsize;
306 
307  for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
308  grpsize = 3 << expstr;
309  for (i = 12; i < 256; i++) {
310  exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
311  exponent_group_tab[1][expstr][i] = (i ) / grpsize;
312  }
313  }
314  /* LFE */
315  exponent_group_tab[0][0][7] = 2;
316 
317  if (CONFIG_EAC3_ENCODER && s->eac3)
319 }
320 
321 
322 /*
323  * Extract exponents from the MDCT coefficients.
324  */
326 {
327  int ch = !s->cpl_on;
328  int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
329  AC3Block *block = &s->blocks[0];
330 
331  s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
332 }
333 
334 
339 #define EXP_DIFF_THRESHOLD 500
340 
344 static const uint8_t exp_strategy_reuse_tab[4][6] = {
345  { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
346  { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
347  { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
348  { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 }
349 };
350 
351 /*
352  * Calculate exponent strategies for all channels.
353  * Array arrangement is reversed to simplify the per-channel calculation.
354  */
356 {
357  int ch, blk, blk1;
358 
359  for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
360  uint8_t *exp_strategy = s->exp_strategy[ch];
361  uint8_t *exp = s->blocks[0].exp[ch];
362  int exp_diff;
363 
364  /* estimate if the exponent variation & decide if they should be
365  reused in the next frame */
366  exp_strategy[0] = EXP_NEW;
367  exp += AC3_MAX_COEFS;
368  for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
369  if (ch == CPL_CH) {
370  if (!s->blocks[blk-1].cpl_in_use) {
371  exp_strategy[blk] = EXP_NEW;
372  continue;
373  } else if (!s->blocks[blk].cpl_in_use) {
374  exp_strategy[blk] = EXP_REUSE;
375  continue;
376  }
377  } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
378  exp_strategy[blk] = EXP_NEW;
379  continue;
380  }
381  exp_diff = s->dsp.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
382  exp_strategy[blk] = EXP_REUSE;
383  if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
384  exp_strategy[blk] = EXP_NEW;
385  else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
386  exp_strategy[blk] = EXP_NEW;
387  }
388 
389  /* now select the encoding strategy type : if exponents are often
390  recoded, we use a coarse encoding */
391  blk = 0;
392  while (blk < s->num_blocks) {
393  blk1 = blk + 1;
394  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
395  blk1++;
396  exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
397  blk = blk1;
398  }
399  }
400  if (s->lfe_on) {
401  ch = s->lfe_channel;
402  s->exp_strategy[ch][0] = EXP_D15;
403  for (blk = 1; blk < s->num_blocks; blk++)
404  s->exp_strategy[ch][blk] = EXP_REUSE;
405  }
406 
407  /* for E-AC-3, determine frame exponent strategy */
408  if (CONFIG_EAC3_ENCODER && s->eac3)
410 }
411 
412 
421 static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
422  int cpl)
423 {
424  int nb_groups, i, k;
425 
426  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
427 
428  /* for each group, compute the minimum exponent */
429  switch(exp_strategy) {
430  case EXP_D25:
431  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
432  uint8_t exp_min = exp[k];
433  if (exp[k+1] < exp_min)
434  exp_min = exp[k+1];
435  exp[i-cpl] = exp_min;
436  k += 2;
437  }
438  break;
439  case EXP_D45:
440  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
441  uint8_t exp_min = exp[k];
442  if (exp[k+1] < exp_min)
443  exp_min = exp[k+1];
444  if (exp[k+2] < exp_min)
445  exp_min = exp[k+2];
446  if (exp[k+3] < exp_min)
447  exp_min = exp[k+3];
448  exp[i-cpl] = exp_min;
449  k += 4;
450  }
451  break;
452  }
453 
454  /* constraint for DC exponent */
455  if (!cpl && exp[0] > 15)
456  exp[0] = 15;
457 
458  /* decrease the delta between each groups to within 2 so that they can be
459  differentially encoded */
460  for (i = 1; i <= nb_groups; i++)
461  exp[i] = FFMIN(exp[i], exp[i-1] + 2);
462  i--;
463  while (--i >= 0)
464  exp[i] = FFMIN(exp[i], exp[i+1] + 2);
465 
466  if (cpl)
467  exp[-1] = exp[0] & ~1;
468 
469  /* now we have the exponent values the decoder will see */
470  switch (exp_strategy) {
471  case EXP_D25:
472  for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
473  uint8_t exp1 = exp[i-cpl];
474  exp[k--] = exp1;
475  exp[k--] = exp1;
476  }
477  break;
478  case EXP_D45:
479  for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
480  exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
481  k -= 4;
482  }
483  break;
484  }
485 }
486 
487 
488 /*
489  * Encode exponents from original extracted form to what the decoder will see.
490  * This copies and groups exponents based on exponent strategy and reduces
491  * deltas between adjacent exponent groups so that they can be differentially
492  * encoded.
493  */
495 {
496  int blk, blk1, ch, cpl;
497  uint8_t *exp, *exp_strategy;
498  int nb_coefs, num_reuse_blocks;
499 
500  for (ch = !s->cpl_on; ch <= s->channels; ch++) {
501  exp = s->blocks[0].exp[ch] + s->start_freq[ch];
502  exp_strategy = s->exp_strategy[ch];
503 
504  cpl = (ch == CPL_CH);
505  blk = 0;
506  while (blk < s->num_blocks) {
507  AC3Block *block = &s->blocks[blk];
508  if (cpl && !block->cpl_in_use) {
509  exp += AC3_MAX_COEFS;
510  blk++;
511  continue;
512  }
513  nb_coefs = block->end_freq[ch] - s->start_freq[ch];
514  blk1 = blk + 1;
515 
516  /* count the number of EXP_REUSE blocks after the current block
517  and set exponent reference block numbers */
518  s->exp_ref_block[ch][blk] = blk;
519  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
520  s->exp_ref_block[ch][blk1] = blk;
521  blk1++;
522  }
523  num_reuse_blocks = blk1 - blk - 1;
524 
525  /* for the EXP_REUSE case we select the min of the exponents */
526  s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
527  AC3_MAX_COEFS);
528 
529  encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
530 
531  exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
532  blk = blk1;
533  }
534  }
535 
536  /* reference block numbers have been changed, so reset ref_bap_set */
537  s->ref_bap_set = 0;
538 }
539 
540 
541 /*
542  * Count exponent bits based on bandwidth, coupling, and exponent strategies.
543  */
545 {
546  int blk, ch;
547  int nb_groups, bit_count;
548 
549  bit_count = 0;
550  for (blk = 0; blk < s->num_blocks; blk++) {
551  AC3Block *block = &s->blocks[blk];
552  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
553  int exp_strategy = s->exp_strategy[ch][blk];
554  int cpl = (ch == CPL_CH);
555  int nb_coefs = block->end_freq[ch] - s->start_freq[ch];
556 
557  if (exp_strategy == EXP_REUSE)
558  continue;
559 
560  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
561  bit_count += 4 + (nb_groups * 7);
562  }
563  }
564 
565  return bit_count;
566 }
567 
568 
577 {
578  int blk, ch, i, cpl;
579  int group_size, nb_groups;
580  uint8_t *p;
581  int delta0, delta1, delta2;
582  int exp0, exp1;
583 
584  for (blk = 0; blk < s->num_blocks; blk++) {
585  AC3Block *block = &s->blocks[blk];
586  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
587  int exp_strategy = s->exp_strategy[ch][blk];
588  if (exp_strategy == EXP_REUSE)
589  continue;
590  cpl = (ch == CPL_CH);
591  group_size = exp_strategy + (exp_strategy == EXP_D45);
592  nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
593  p = block->exp[ch] + s->start_freq[ch] - cpl;
594 
595  /* DC exponent */
596  exp1 = *p++;
597  block->grouped_exp[ch][0] = exp1;
598 
599  /* remaining exponents are delta encoded */
600  for (i = 1; i <= nb_groups; i++) {
601  /* merge three delta in one code */
602  exp0 = exp1;
603  exp1 = p[0];
604  p += group_size;
605  delta0 = exp1 - exp0 + 2;
606  av_assert2(delta0 >= 0 && delta0 <= 4);
607 
608  exp0 = exp1;
609  exp1 = p[0];
610  p += group_size;
611  delta1 = exp1 - exp0 + 2;
612  av_assert2(delta1 >= 0 && delta1 <= 4);
613 
614  exp0 = exp1;
615  exp1 = p[0];
616  p += group_size;
617  delta2 = exp1 - exp0 + 2;
618  av_assert2(delta2 >= 0 && delta2 <= 4);
619 
620  block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
621  }
622  }
623  }
624 }
625 
626 
635 {
637 
639 
640  encode_exponents(s);
641 
642  emms_c();
643 }
644 
645 
646 /*
647  * Count frame bits that are based solely on fixed parameters.
648  * This only has to be run once when the encoder is initialized.
649  */
651 {
652  static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
653  int blk;
654  int frame_bits;
655 
656  /* assumptions:
657  * no dynamic range codes
658  * bit allocation parameters do not change between blocks
659  * no delta bit allocation
660  * no skipped data
661  * no auxiliary data
662  * no E-AC-3 metadata
663  */
664 
665  /* header */
666  frame_bits = 16; /* sync info */
667  if (s->eac3) {
668  /* bitstream info header */
669  frame_bits += 35;
670  frame_bits += 1 + 1;
671  if (s->num_blocks != 0x6)
672  frame_bits++;
673  frame_bits++;
674  /* audio frame header */
675  if (s->num_blocks == 6)
676  frame_bits += 2;
677  frame_bits += 10;
678  /* exponent strategy */
679  if (s->use_frame_exp_strategy)
680  frame_bits += 5 * s->fbw_channels;
681  else
682  frame_bits += s->num_blocks * 2 * s->fbw_channels;
683  if (s->lfe_on)
684  frame_bits += s->num_blocks;
685  /* converter exponent strategy */
686  if (s->num_blks_code != 0x3)
687  frame_bits++;
688  else
689  frame_bits += s->fbw_channels * 5;
690  /* snr offsets */
691  frame_bits += 10;
692  /* block start info */
693  if (s->num_blocks != 1)
694  frame_bits++;
695  } else {
696  frame_bits += 49;
697  frame_bits += frame_bits_inc[s->channel_mode];
698  }
699 
700  /* audio blocks */
701  for (blk = 0; blk < s->num_blocks; blk++) {
702  if (!s->eac3) {
703  /* block switch flags */
704  frame_bits += s->fbw_channels;
705 
706  /* dither flags */
707  frame_bits += s->fbw_channels;
708  }
709 
710  /* dynamic range */
711  frame_bits++;
712 
713  /* spectral extension */
714  if (s->eac3)
715  frame_bits++;
716 
717  if (!s->eac3) {
718  /* exponent strategy */
719  frame_bits += 2 * s->fbw_channels;
720  if (s->lfe_on)
721  frame_bits++;
722 
723  /* bit allocation params */
724  frame_bits++;
725  if (!blk)
726  frame_bits += 2 + 2 + 2 + 2 + 3;
727  }
728 
729  /* converter snr offset */
730  if (s->eac3)
731  frame_bits++;
732 
733  if (!s->eac3) {
734  /* delta bit allocation */
735  frame_bits++;
736 
737  /* skipped data */
738  frame_bits++;
739  }
740  }
741 
742  /* auxiliary data */
743  frame_bits++;
744 
745  /* CRC */
746  frame_bits += 1 + 16;
747 
748  s->frame_bits_fixed = frame_bits;
749 }
750 
751 
752 /*
753  * Initialize bit allocation.
754  * Set default parameter codes and calculate parameter values.
755  */
757 {
758  int ch;
759 
760  /* init default parameters */
761  s->slow_decay_code = 2;
762  s->fast_decay_code = 1;
763  s->slow_gain_code = 1;
764  s->db_per_bit_code = s->eac3 ? 2 : 3;
765  s->floor_code = 7;
766  for (ch = 0; ch <= s->channels; ch++)
767  s->fast_gain_code[ch] = 4;
768 
769  /* initial snr offset */
770  s->coarse_snr_offset = 40;
771 
772  /* compute real values */
773  /* currently none of these values change during encoding, so we can just
774  set them once at initialization */
780  s->bit_alloc.cpl_fast_leak = 0;
781  s->bit_alloc.cpl_slow_leak = 0;
782 
784 }
785 
786 
787 /*
788  * Count the bits used to encode the frame, minus exponents and mantissas.
789  * Bits based on fixed parameters have already been counted, so now we just
790  * have to add the bits based on parameters that change during encoding.
791  */
793 {
794  AC3EncOptions *opt = &s->options;
795  int blk, ch;
796  int frame_bits = 0;
797 
798  /* header */
799  if (s->eac3) {
800  if (opt->eac3_mixing_metadata) {
802  frame_bits += 2;
803  if (s->has_center)
804  frame_bits += 6;
805  if (s->has_surround)
806  frame_bits += 6;
807  frame_bits += s->lfe_on;
808  frame_bits += 1 + 1 + 2;
810  frame_bits++;
811  frame_bits++;
812  }
813  if (opt->eac3_info_metadata) {
814  frame_bits += 3 + 1 + 1;
816  frame_bits += 2 + 2;
817  if (s->channel_mode >= AC3_CHMODE_2F2R)
818  frame_bits += 2;
819  frame_bits++;
820  if (opt->audio_production_info)
821  frame_bits += 5 + 2 + 1;
822  frame_bits++;
823  }
824  /* coupling */
825  if (s->channel_mode > AC3_CHMODE_MONO) {
826  frame_bits++;
827  for (blk = 1; blk < s->num_blocks; blk++) {
828  AC3Block *block = &s->blocks[blk];
829  frame_bits++;
830  if (block->new_cpl_strategy)
831  frame_bits++;
832  }
833  }
834  /* coupling exponent strategy */
835  if (s->cpl_on) {
836  if (s->use_frame_exp_strategy) {
837  frame_bits += 5 * s->cpl_on;
838  } else {
839  for (blk = 0; blk < s->num_blocks; blk++)
840  frame_bits += 2 * s->blocks[blk].cpl_in_use;
841  }
842  }
843  } else {
844  if (opt->audio_production_info)
845  frame_bits += 7;
846  if (s->bitstream_id == 6) {
847  if (opt->extended_bsi_1)
848  frame_bits += 14;
849  if (opt->extended_bsi_2)
850  frame_bits += 14;
851  }
852  }
853 
854  /* audio blocks */
855  for (blk = 0; blk < s->num_blocks; blk++) {
856  AC3Block *block = &s->blocks[blk];
857 
858  /* coupling strategy */
859  if (!s->eac3)
860  frame_bits++;
861  if (block->new_cpl_strategy) {
862  if (!s->eac3)
863  frame_bits++;
864  if (block->cpl_in_use) {
865  if (s->eac3)
866  frame_bits++;
867  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
868  frame_bits += s->fbw_channels;
870  frame_bits++;
871  frame_bits += 4 + 4;
872  if (s->eac3)
873  frame_bits++;
874  else
875  frame_bits += s->num_cpl_subbands - 1;
876  }
877  }
878 
879  /* coupling coordinates */
880  if (block->cpl_in_use) {
881  for (ch = 1; ch <= s->fbw_channels; ch++) {
882  if (block->channel_in_cpl[ch]) {
883  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
884  frame_bits++;
885  if (block->new_cpl_coords[ch]) {
886  frame_bits += 2;
887  frame_bits += (4 + 4) * s->num_cpl_bands;
888  }
889  }
890  }
891  }
892 
893  /* stereo rematrixing */
894  if (s->channel_mode == AC3_CHMODE_STEREO) {
895  if (!s->eac3 || blk > 0)
896  frame_bits++;
897  if (s->blocks[blk].new_rematrixing_strategy)
898  frame_bits += block->num_rematrixing_bands;
899  }
900 
901  /* bandwidth codes & gain range */
902  for (ch = 1; ch <= s->fbw_channels; ch++) {
903  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
904  if (!block->channel_in_cpl[ch])
905  frame_bits += 6;
906  frame_bits += 2;
907  }
908  }
909 
910  /* coupling exponent strategy */
911  if (!s->eac3 && block->cpl_in_use)
912  frame_bits += 2;
913 
914  /* snr offsets and fast gain codes */
915  if (!s->eac3) {
916  frame_bits++;
917  if (block->new_snr_offsets)
918  frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
919  }
920 
921  /* coupling leak info */
922  if (block->cpl_in_use) {
923  if (!s->eac3 || block->new_cpl_leak != 2)
924  frame_bits++;
925  if (block->new_cpl_leak)
926  frame_bits += 3 + 3;
927  }
928  }
929 
930  s->frame_bits = s->frame_bits_fixed + frame_bits;
931 }
932 
933 
934 /*
935  * Calculate masking curve based on the final exponents.
936  * Also calculate the power spectral densities to use in future calculations.
937  */
939 {
940  int blk, ch;
941 
942  for (blk = 0; blk < s->num_blocks; blk++) {
943  AC3Block *block = &s->blocks[blk];
944  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
945  /* We only need psd and mask for calculating bap.
946  Since we currently do not calculate bap when exponent
947  strategy is EXP_REUSE we do not need to calculate psd or mask. */
948  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
949  ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
950  block->end_freq[ch], block->psd[ch],
951  block->band_psd[ch]);
953  s->start_freq[ch], block->end_freq[ch],
955  ch == s->lfe_channel,
956  DBA_NONE, 0, NULL, NULL, NULL,
957  block->mask[ch]);
958  }
959  }
960  }
961 }
962 
963 
964 /*
965  * Ensure that bap for each block and channel point to the current bap_buffer.
966  * They may have been switched during the bit allocation search.
967  */
969 {
970  int blk, ch;
971  uint8_t *ref_bap;
972 
973  if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
974  return;
975 
976  ref_bap = s->bap_buffer;
977  for (ch = 0; ch <= s->channels; ch++) {
978  for (blk = 0; blk < s->num_blocks; blk++)
979  s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
980  ref_bap += AC3_MAX_COEFS * s->num_blocks;
981  }
982  s->ref_bap_set = 1;
983 }
984 
985 
993 static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
994 {
995  int blk;
996 
997  for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
998  memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
999  mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
1000  mant_cnt[blk][4] = 1;
1001  }
1002 }
1003 
1004 
1016  uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
1017  int start, int end)
1018 {
1019  int blk;
1020 
1021  for (blk = 0; blk < s->num_blocks; blk++) {
1022  AC3Block *block = &s->blocks[blk];
1023  if (ch == CPL_CH && !block->cpl_in_use)
1024  continue;
1025  s->ac3dsp.update_bap_counts(mant_cnt[blk],
1026  s->ref_bap[ch][blk] + start,
1027  FFMIN(end, block->end_freq[ch]) - start);
1028  }
1029 }
1030 
1031 
1032 /*
1033  * Count the number of mantissa bits in the frame based on the bap values.
1034  */
1036 {
1037  int ch, max_end_freq;
1038  LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
1039 
1040  count_mantissa_bits_init(mant_cnt);
1041 
1042  max_end_freq = s->bandwidth_code * 3 + 73;
1043  for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
1044  count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
1045  max_end_freq);
1046 
1047  return s->ac3dsp.compute_mantissa_size(mant_cnt);
1048 }
1049 
1050 
1061 static int bit_alloc(AC3EncodeContext *s, int snr_offset)
1062 {
1063  int blk, ch;
1064 
1065  snr_offset = (snr_offset - 240) << 2;
1066 
1067  reset_block_bap(s);
1068  for (blk = 0; blk < s->num_blocks; blk++) {
1069  AC3Block *block = &s->blocks[blk];
1070 
1071  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1072  /* Currently the only bit allocation parameters which vary across
1073  blocks within a frame are the exponent values. We can take
1074  advantage of that by reusing the bit allocation pointers
1075  whenever we reuse exponents. */
1076  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1077  s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
1078  s->start_freq[ch], block->end_freq[ch],
1079  snr_offset, s->bit_alloc.floor,
1080  ff_ac3_bap_tab, s->ref_bap[ch][blk]);
1081  }
1082  }
1083  }
1084  return count_mantissa_bits(s);
1085 }
1086 
1087 
1088 /*
1089  * Constant bitrate bit allocation search.
1090  * Find the largest SNR offset that will allow data to fit in the frame.
1091  */
1093 {
1094  int ch;
1095  int bits_left;
1096  int snr_offset, snr_incr;
1097 
1098  bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
1099  if (bits_left < 0)
1100  return AVERROR(EINVAL);
1101 
1102  snr_offset = s->coarse_snr_offset << 4;
1103 
1104  /* if previous frame SNR offset was 1023, check if current frame can also
1105  use SNR offset of 1023. if so, skip the search. */
1106  if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
1107  if (bit_alloc(s, 1023) <= bits_left)
1108  return 0;
1109  }
1110 
1111  while (snr_offset >= 0 &&
1112  bit_alloc(s, snr_offset) > bits_left) {
1113  snr_offset -= 64;
1114  }
1115  if (snr_offset < 0)
1116  return AVERROR(EINVAL);
1117 
1118  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1119  for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
1120  while (snr_offset + snr_incr <= 1023 &&
1121  bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
1122  snr_offset += snr_incr;
1123  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1124  }
1125  }
1126  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1127  reset_block_bap(s);
1128 
1129  s->coarse_snr_offset = snr_offset >> 4;
1130  for (ch = !s->cpl_on; ch <= s->channels; ch++)
1131  s->fine_snr_offset[ch] = snr_offset & 0xF;
1132 
1133  return 0;
1134 }
1135 
1136 
1137 /*
1138  * Perform bit allocation search.
1139  * Finds the SNR offset value that maximizes quality and fits in the specified
1140  * frame size. Output is the SNR offset and a set of bit allocation pointers
1141  * used to quantize the mantissas.
1142  */
1144 {
1145  count_frame_bits(s);
1146 
1148 
1149  bit_alloc_masking(s);
1150 
1151  return cbr_bit_allocation(s);
1152 }
1153 
1154 
1163 static inline int sym_quant(int c, int e, int levels)
1164 {
1165  int v = (((levels * c) >> (24 - e)) + levels) >> 1;
1166  av_assert2(v >= 0 && v < levels);
1167  return v;
1168 }
1169 
1170 
1179 static inline int asym_quant(int c, int e, int qbits)
1180 {
1181  int m;
1182 
1183  c = (((c << e) >> (24 - qbits)) + 1) >> 1;
1184  m = (1 << (qbits-1));
1185  if (c >= m)
1186  c = m - 1;
1187  av_assert2(c >= -m);
1188  return c;
1189 }
1190 
1191 
1203 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
1204  uint8_t *exp, uint8_t *bap,
1205  int16_t *qmant, int start_freq,
1206  int end_freq)
1207 {
1208  int i;
1209 
1210  for (i = start_freq; i < end_freq; i++) {
1211  int v;
1212  int c = fixed_coef[i];
1213  int e = exp[i];
1214  int b = bap[i];
1215  switch (b) {
1216  case 0:
1217  v = 0;
1218  break;
1219  case 1:
1220  v = sym_quant(c, e, 3);
1221  switch (s->mant1_cnt) {
1222  case 0:
1223  s->qmant1_ptr = &qmant[i];
1224  v = 9 * v;
1225  s->mant1_cnt = 1;
1226  break;
1227  case 1:
1228  *s->qmant1_ptr += 3 * v;
1229  s->mant1_cnt = 2;
1230  v = 128;
1231  break;
1232  default:
1233  *s->qmant1_ptr += v;
1234  s->mant1_cnt = 0;
1235  v = 128;
1236  break;
1237  }
1238  break;
1239  case 2:
1240  v = sym_quant(c, e, 5);
1241  switch (s->mant2_cnt) {
1242  case 0:
1243  s->qmant2_ptr = &qmant[i];
1244  v = 25 * v;
1245  s->mant2_cnt = 1;
1246  break;
1247  case 1:
1248  *s->qmant2_ptr += 5 * v;
1249  s->mant2_cnt = 2;
1250  v = 128;
1251  break;
1252  default:
1253  *s->qmant2_ptr += v;
1254  s->mant2_cnt = 0;
1255  v = 128;
1256  break;
1257  }
1258  break;
1259  case 3:
1260  v = sym_quant(c, e, 7);
1261  break;
1262  case 4:
1263  v = sym_quant(c, e, 11);
1264  switch (s->mant4_cnt) {
1265  case 0:
1266  s->qmant4_ptr = &qmant[i];
1267  v = 11 * v;
1268  s->mant4_cnt = 1;
1269  break;
1270  default:
1271  *s->qmant4_ptr += v;
1272  s->mant4_cnt = 0;
1273  v = 128;
1274  break;
1275  }
1276  break;
1277  case 5:
1278  v = sym_quant(c, e, 15);
1279  break;
1280  case 14:
1281  v = asym_quant(c, e, 14);
1282  break;
1283  case 15:
1284  v = asym_quant(c, e, 16);
1285  break;
1286  default:
1287  v = asym_quant(c, e, b - 1);
1288  break;
1289  }
1290  qmant[i] = v;
1291  }
1292 }
1293 
1294 
1301 {
1302  int blk, ch, ch0=0, got_cpl;
1303 
1304  for (blk = 0; blk < s->num_blocks; blk++) {
1305  AC3Block *block = &s->blocks[blk];
1306  AC3Mant m = { 0 };
1307 
1308  got_cpl = !block->cpl_in_use;
1309  for (ch = 1; ch <= s->channels; ch++) {
1310  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1311  ch0 = ch - 1;
1312  ch = CPL_CH;
1313  got_cpl = 1;
1314  }
1315  quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
1316  s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
1317  s->ref_bap[ch][blk], block->qmant[ch],
1318  s->start_freq[ch], block->end_freq[ch]);
1319  if (ch == CPL_CH)
1320  ch = ch0;
1321  }
1322  }
1323 }
1324 
1325 
1326 /*
1327  * Write the AC-3 frame header to the output bitstream.
1328  */
1330 {
1331  AC3EncOptions *opt = &s->options;
1332 
1333  put_bits(&s->pb, 16, 0x0b77); /* frame header */
1334  put_bits(&s->pb, 16, 0); /* crc1: will be filled later */
1335  put_bits(&s->pb, 2, s->bit_alloc.sr_code);
1336  put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
1337  put_bits(&s->pb, 5, s->bitstream_id);
1338  put_bits(&s->pb, 3, s->bitstream_mode);
1339  put_bits(&s->pb, 3, s->channel_mode);
1340  if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
1341  put_bits(&s->pb, 2, s->center_mix_level);
1342  if (s->channel_mode & 0x04)
1343  put_bits(&s->pb, 2, s->surround_mix_level);
1344  if (s->channel_mode == AC3_CHMODE_STEREO)
1345  put_bits(&s->pb, 2, opt->dolby_surround_mode);
1346  put_bits(&s->pb, 1, s->lfe_on); /* LFE */
1347  put_bits(&s->pb, 5, -opt->dialogue_level);
1348  put_bits(&s->pb, 1, 0); /* no compression control word */
1349  put_bits(&s->pb, 1, 0); /* no lang code */
1350  put_bits(&s->pb, 1, opt->audio_production_info);
1351  if (opt->audio_production_info) {
1352  put_bits(&s->pb, 5, opt->mixing_level - 80);
1353  put_bits(&s->pb, 2, opt->room_type);
1354  }
1355  put_bits(&s->pb, 1, opt->copyright);
1356  put_bits(&s->pb, 1, opt->original);
1357  if (s->bitstream_id == 6) {
1358  /* alternate bit stream syntax */
1359  put_bits(&s->pb, 1, opt->extended_bsi_1);
1360  if (opt->extended_bsi_1) {
1361  put_bits(&s->pb, 2, opt->preferred_stereo_downmix);
1362  put_bits(&s->pb, 3, s->ltrt_center_mix_level);
1363  put_bits(&s->pb, 3, s->ltrt_surround_mix_level);
1364  put_bits(&s->pb, 3, s->loro_center_mix_level);
1365  put_bits(&s->pb, 3, s->loro_surround_mix_level);
1366  }
1367  put_bits(&s->pb, 1, opt->extended_bsi_2);
1368  if (opt->extended_bsi_2) {
1369  put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);
1370  put_bits(&s->pb, 2, opt->dolby_headphone_mode);
1371  put_bits(&s->pb, 1, opt->ad_converter_type);
1372  put_bits(&s->pb, 9, 0); /* xbsi2 and encinfo : reserved */
1373  }
1374  } else {
1375  put_bits(&s->pb, 1, 0); /* no time code 1 */
1376  put_bits(&s->pb, 1, 0); /* no time code 2 */
1377  }
1378  put_bits(&s->pb, 1, 0); /* no additional bit stream info */
1379 }
1380 
1381 
1382 /*
1383  * Write one audio block to the output bitstream.
1384  */
1386 {
1387  int ch, i, baie, bnd, got_cpl, ch0;
1388  AC3Block *block = &s->blocks[blk];
1389 
1390  /* block switching */
1391  if (!s->eac3) {
1392  for (ch = 0; ch < s->fbw_channels; ch++)
1393  put_bits(&s->pb, 1, 0);
1394  }
1395 
1396  /* dither flags */
1397  if (!s->eac3) {
1398  for (ch = 0; ch < s->fbw_channels; ch++)
1399  put_bits(&s->pb, 1, 1);
1400  }
1401 
1402  /* dynamic range codes */
1403  put_bits(&s->pb, 1, 0);
1404 
1405  /* spectral extension */
1406  if (s->eac3)
1407  put_bits(&s->pb, 1, 0);
1408 
1409  /* channel coupling */
1410  if (!s->eac3)
1411  put_bits(&s->pb, 1, block->new_cpl_strategy);
1412  if (block->new_cpl_strategy) {
1413  if (!s->eac3)
1414  put_bits(&s->pb, 1, block->cpl_in_use);
1415  if (block->cpl_in_use) {
1416  int start_sub, end_sub;
1417  if (s->eac3)
1418  put_bits(&s->pb, 1, 0); /* enhanced coupling */
1419  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
1420  for (ch = 1; ch <= s->fbw_channels; ch++)
1421  put_bits(&s->pb, 1, block->channel_in_cpl[ch]);
1422  }
1423  if (s->channel_mode == AC3_CHMODE_STEREO)
1424  put_bits(&s->pb, 1, 0); /* phase flags in use */
1425  start_sub = (s->start_freq[CPL_CH] - 37) / 12;
1426  end_sub = (s->cpl_end_freq - 37) / 12;
1427  put_bits(&s->pb, 4, start_sub);
1428  put_bits(&s->pb, 4, end_sub - 3);
1429  /* coupling band structure */
1430  if (s->eac3) {
1431  put_bits(&s->pb, 1, 0); /* use default */
1432  } else {
1433  for (bnd = start_sub+1; bnd < end_sub; bnd++)
1435  }
1436  }
1437  }
1438 
1439  /* coupling coordinates */
1440  if (block->cpl_in_use) {
1441  for (ch = 1; ch <= s->fbw_channels; ch++) {
1442  if (block->channel_in_cpl[ch]) {
1443  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1444  put_bits(&s->pb, 1, block->new_cpl_coords[ch]);
1445  if (block->new_cpl_coords[ch]) {
1446  put_bits(&s->pb, 2, block->cpl_master_exp[ch]);
1447  for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
1448  put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);
1449  put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]);
1450  }
1451  }
1452  }
1453  }
1454  }
1455 
1456  /* stereo rematrixing */
1457  if (s->channel_mode == AC3_CHMODE_STEREO) {
1458  if (!s->eac3 || blk > 0)
1459  put_bits(&s->pb, 1, block->new_rematrixing_strategy);
1460  if (block->new_rematrixing_strategy) {
1461  /* rematrixing flags */
1462  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
1463  put_bits(&s->pb, 1, block->rematrixing_flags[bnd]);
1464  }
1465  }
1466 
1467  /* exponent strategy */
1468  if (!s->eac3) {
1469  for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
1470  put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
1471  if (s->lfe_on)
1472  put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
1473  }
1474 
1475  /* bandwidth */
1476  for (ch = 1; ch <= s->fbw_channels; ch++) {
1477  if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
1478  put_bits(&s->pb, 6, s->bandwidth_code);
1479  }
1480 
1481  /* exponents */
1482  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1483  int nb_groups;
1484  int cpl = (ch == CPL_CH);
1485 
1486  if (s->exp_strategy[ch][blk] == EXP_REUSE)
1487  continue;
1488 
1489  /* DC exponent */
1490  put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl);
1491 
1492  /* exponent groups */
1493  nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
1494  for (i = 1; i <= nb_groups; i++)
1495  put_bits(&s->pb, 7, block->grouped_exp[ch][i]);
1496 
1497  /* gain range info */
1498  if (ch != s->lfe_channel && !cpl)
1499  put_bits(&s->pb, 2, 0);
1500  }
1501 
1502  /* bit allocation info */
1503  if (!s->eac3) {
1504  baie = (blk == 0);
1505  put_bits(&s->pb, 1, baie);
1506  if (baie) {
1507  put_bits(&s->pb, 2, s->slow_decay_code);
1508  put_bits(&s->pb, 2, s->fast_decay_code);
1509  put_bits(&s->pb, 2, s->slow_gain_code);
1510  put_bits(&s->pb, 2, s->db_per_bit_code);
1511  put_bits(&s->pb, 3, s->floor_code);
1512  }
1513  }
1514 
1515  /* snr offset */
1516  if (!s->eac3) {
1517  put_bits(&s->pb, 1, block->new_snr_offsets);
1518  if (block->new_snr_offsets) {
1519  put_bits(&s->pb, 6, s->coarse_snr_offset);
1520  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1521  put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
1522  put_bits(&s->pb, 3, s->fast_gain_code[ch]);
1523  }
1524  }
1525  } else {
1526  put_bits(&s->pb, 1, 0); /* no converter snr offset */
1527  }
1528 
1529  /* coupling leak */
1530  if (block->cpl_in_use) {
1531  if (!s->eac3 || block->new_cpl_leak != 2)
1532  put_bits(&s->pb, 1, block->new_cpl_leak);
1533  if (block->new_cpl_leak) {
1534  put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak);
1535  put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak);
1536  }
1537  }
1538 
1539  if (!s->eac3) {
1540  put_bits(&s->pb, 1, 0); /* no delta bit allocation */
1541  put_bits(&s->pb, 1, 0); /* no data to skip */
1542  }
1543 
1544  /* mantissas */
1545  got_cpl = !block->cpl_in_use;
1546  for (ch = 1; ch <= s->channels; ch++) {
1547  int b, q;
1548 
1549  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1550  ch0 = ch - 1;
1551  ch = CPL_CH;
1552  got_cpl = 1;
1553  }
1554  for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
1555  q = block->qmant[ch][i];
1556  b = s->ref_bap[ch][blk][i];
1557  switch (b) {
1558  case 0: break;
1559  case 1: if (q != 128) put_bits (&s->pb, 5, q); break;
1560  case 2: if (q != 128) put_bits (&s->pb, 7, q); break;
1561  case 3: put_sbits(&s->pb, 3, q); break;
1562  case 4: if (q != 128) put_bits (&s->pb, 7, q); break;
1563  case 14: put_sbits(&s->pb, 14, q); break;
1564  case 15: put_sbits(&s->pb, 16, q); break;
1565  default: put_sbits(&s->pb, b-1, q); break;
1566  }
1567  }
1568  if (ch == CPL_CH)
1569  ch = ch0;
1570  }
1571 }
1572 
1573 
1575 #define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
1576 
1577 
1578 static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
1579 {
1580  unsigned int c;
1581 
1582  c = 0;
1583  while (a) {
1584  if (a & 1)
1585  c ^= b;
1586  a = a >> 1;
1587  b = b << 1;
1588  if (b & (1 << 16))
1589  b ^= poly;
1590  }
1591  return c;
1592 }
1593 
1594 
1595 static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
1596 {
1597  unsigned int r;
1598  r = 1;
1599  while (n) {
1600  if (n & 1)
1601  r = mul_poly(r, a, poly);
1602  a = mul_poly(a, a, poly);
1603  n >>= 1;
1604  }
1605  return r;
1606 }
1607 
1608 
1609 /*
1610  * Fill the end of the frame with 0's and compute the two CRCs.
1611  */
1613 {
1614  const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
1615  int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv;
1616  uint8_t *frame;
1617 
1618  frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
1619 
1620  /* pad the remainder of the frame with zeros */
1621  av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18);
1622  flush_put_bits(&s->pb);
1623  frame = s->pb.buf;
1624  pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
1625  av_assert2(pad_bytes >= 0);
1626  if (pad_bytes > 0)
1627  memset(put_bits_ptr(&s->pb), 0, pad_bytes);
1628 
1629  if (s->eac3) {
1630  /* compute crc2 */
1631  crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5);
1632  } else {
1633  /* compute crc1 */
1634  /* this is not so easy because it is at the beginning of the data... */
1635  crc1 = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
1636  crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
1637  crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
1638  AV_WB16(frame + 2, crc1);
1639 
1640  /* compute crc2 */
1641  crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58,
1642  s->frame_size - frame_size_58 - 3);
1643  }
1644  crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1645  /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
1646  if (crc2 == 0x770B) {
1647  frame[s->frame_size - 3] ^= 0x1;
1648  crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1649  }
1650  crc2 = av_bswap16(crc2);
1651  AV_WB16(frame + s->frame_size - 2, crc2);
1652 }
1653 
1654 
1661 void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
1662 {
1663  int blk;
1664 
1666 
1667  s->output_frame_header(s);
1668 
1669  for (blk = 0; blk < s->num_blocks; blk++)
1670  output_audio_block(s, blk);
1671 
1672  output_frame_end(s);
1673 }
1674 
1675 
1677 {
1678 #ifdef DEBUG
1679  AVCodecContext *avctx = s->avctx;
1680  AC3EncOptions *opt = &s->options;
1681  char strbuf[32];
1682 
1683  switch (s->bitstream_id) {
1684  case 6: av_strlcpy(strbuf, "AC-3 (alt syntax)", 32); break;
1685  case 8: av_strlcpy(strbuf, "AC-3 (standard)", 32); break;
1686  case 9: av_strlcpy(strbuf, "AC-3 (dnet half-rate)", 32); break;
1687  case 10: av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break;
1688  case 16: av_strlcpy(strbuf, "E-AC-3 (enhanced)", 32); break;
1689  default: snprintf(strbuf, 32, "ERROR");
1690  }
1691  av_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id);
1692  av_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
1693  av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout);
1694  av_dlog(avctx, "channel_layout: %s\n", strbuf);
1695  av_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
1696  av_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
1697  av_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
1698  if (s->cutoff)
1699  av_dlog(avctx, "cutoff: %d\n", s->cutoff);
1700 
1701  av_dlog(avctx, "per_frame_metadata: %s\n",
1702  opt->allow_per_frame_metadata?"on":"off");
1703  if (s->has_center)
1704  av_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
1705  s->center_mix_level);
1706  else
1707  av_dlog(avctx, "center_mixlev: {not written}\n");
1708  if (s->has_surround)
1709  av_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
1710  s->surround_mix_level);
1711  else
1712  av_dlog(avctx, "surround_mixlev: {not written}\n");
1713  if (opt->audio_production_info) {
1714  av_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
1715  switch (opt->room_type) {
1716  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1717  case AC3ENC_OPT_LARGE_ROOM: av_strlcpy(strbuf, "large", 32); break;
1718  case AC3ENC_OPT_SMALL_ROOM: av_strlcpy(strbuf, "small", 32); break;
1719  default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type);
1720  }
1721  av_dlog(avctx, "room_type: %s\n", strbuf);
1722  } else {
1723  av_dlog(avctx, "mixing_level: {not written}\n");
1724  av_dlog(avctx, "room_type: {not written}\n");
1725  }
1726  av_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
1727  av_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
1728  if (s->channel_mode == AC3_CHMODE_STEREO) {
1729  switch (opt->dolby_surround_mode) {
1730  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1731  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1732  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1733  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode);
1734  }
1735  av_dlog(avctx, "dsur_mode: %s\n", strbuf);
1736  } else {
1737  av_dlog(avctx, "dsur_mode: {not written}\n");
1738  }
1739  av_dlog(avctx, "original: %s\n", opt->original?"on":"off");
1740 
1741  if (s->bitstream_id == 6) {
1742  if (opt->extended_bsi_1) {
1743  switch (opt->preferred_stereo_downmix) {
1744  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1745  case AC3ENC_OPT_DOWNMIX_LTRT: av_strlcpy(strbuf, "ltrt", 32); break;
1746  case AC3ENC_OPT_DOWNMIX_LORO: av_strlcpy(strbuf, "loro", 32); break;
1747  default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix);
1748  }
1749  av_dlog(avctx, "dmix_mode: %s\n", strbuf);
1750  av_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
1752  av_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
1754  av_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
1756  av_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
1758  } else {
1759  av_dlog(avctx, "extended bitstream info 1: {not written}\n");
1760  }
1761  if (opt->extended_bsi_2) {
1762  switch (opt->dolby_surround_ex_mode) {
1763  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1764  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1765  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1766  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode);
1767  }
1768  av_dlog(avctx, "dsurex_mode: %s\n", strbuf);
1769  switch (opt->dolby_headphone_mode) {
1770  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1771  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1772  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1773  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode);
1774  }
1775  av_dlog(avctx, "dheadphone_mode: %s\n", strbuf);
1776 
1777  switch (opt->ad_converter_type) {
1778  case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break;
1779  case AC3ENC_OPT_ADCONV_HDCD: av_strlcpy(strbuf, "hdcd", 32); break;
1780  default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type);
1781  }
1782  av_dlog(avctx, "ad_conv_type: %s\n", strbuf);
1783  } else {
1784  av_dlog(avctx, "extended bitstream info 2: {not written}\n");
1785  }
1786  }
1787 #endif
1788 }
1789 
1790 
1791 #define FLT_OPTION_THRESHOLD 0.01
1792 
1793 static int validate_float_option(float v, const float *v_list, int v_list_size)
1794 {
1795  int i;
1796 
1797  for (i = 0; i < v_list_size; i++) {
1798  if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
1799  v > (v_list[i] - FLT_OPTION_THRESHOLD))
1800  break;
1801  }
1802  if (i == v_list_size)
1803  return -1;
1804 
1805  return i;
1806 }
1807 
1808 
1809 static void validate_mix_level(void *log_ctx, const char *opt_name,
1810  float *opt_param, const float *list,
1811  int list_size, int default_value, int min_value,
1812  int *ctx_param)
1813 {
1814  int mixlev = validate_float_option(*opt_param, list, list_size);
1815  if (mixlev < min_value) {
1816  mixlev = default_value;
1817  if (*opt_param >= 0.0) {
1818  av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
1819  "default value: %0.3f\n", opt_name, list[mixlev]);
1820  }
1821  }
1822  *opt_param = list[mixlev];
1823  *ctx_param = mixlev;
1824 }
1825 
1826 
1834 {
1835  AVCodecContext *avctx = s->avctx;
1836  AC3EncOptions *opt = &s->options;
1837 
1838  opt->audio_production_info = 0;
1839  opt->extended_bsi_1 = 0;
1840  opt->extended_bsi_2 = 0;
1841  opt->eac3_mixing_metadata = 0;
1842  opt->eac3_info_metadata = 0;
1843 
1844  /* determine mixing metadata / xbsi1 use */
1846  opt->extended_bsi_1 = 1;
1847  opt->eac3_mixing_metadata = 1;
1848  }
1849  if (s->has_center &&
1850  (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
1851  opt->extended_bsi_1 = 1;
1852  opt->eac3_mixing_metadata = 1;
1853  }
1854  if (s->has_surround &&
1855  (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
1856  opt->extended_bsi_1 = 1;
1857  opt->eac3_mixing_metadata = 1;
1858  }
1859 
1860  if (s->eac3) {
1861  /* determine info metadata use */
1863  opt->eac3_info_metadata = 1;
1864  if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
1865  opt->eac3_info_metadata = 1;
1866  if (s->channel_mode == AC3_CHMODE_STEREO &&
1868  opt->eac3_info_metadata = 1;
1870  opt->eac3_info_metadata = 1;
1871  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
1873  opt->audio_production_info = 1;
1874  opt->eac3_info_metadata = 1;
1875  }
1876  } else {
1877  /* determine audio production info use */
1878  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
1879  opt->audio_production_info = 1;
1880 
1881  /* determine xbsi2 use */
1883  opt->extended_bsi_2 = 1;
1885  opt->extended_bsi_2 = 1;
1886  if (opt->ad_converter_type != AC3ENC_OPT_NONE)
1887  opt->extended_bsi_2 = 1;
1888  }
1889 
1890  /* validate AC-3 mixing levels */
1891  if (!s->eac3) {
1892  if (s->has_center) {
1893  validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
1895  &s->center_mix_level);
1896  }
1897  if (s->has_surround) {
1898  validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
1900  &s->surround_mix_level);
1901  }
1902  }
1903 
1904  /* validate extended bsi 1 / mixing metadata */
1905  if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
1906  /* default preferred stereo downmix */
1909  if (!s->eac3 || s->has_center) {
1910  /* validate Lt/Rt center mix level */
1911  validate_mix_level(avctx, "ltrt_center_mix_level",
1913  EXTMIXLEV_NUM_OPTIONS, 5, 0,
1914  &s->ltrt_center_mix_level);
1915  /* validate Lo/Ro center mix level */
1916  validate_mix_level(avctx, "loro_center_mix_level",
1918  EXTMIXLEV_NUM_OPTIONS, 5, 0,
1919  &s->loro_center_mix_level);
1920  }
1921  if (!s->eac3 || s->has_surround) {
1922  /* validate Lt/Rt surround mix level */
1923  validate_mix_level(avctx, "ltrt_surround_mix_level",
1925  EXTMIXLEV_NUM_OPTIONS, 6, 3,
1927  /* validate Lo/Ro surround mix level */
1928  validate_mix_level(avctx, "loro_surround_mix_level",
1930  EXTMIXLEV_NUM_OPTIONS, 6, 3,
1932  }
1933  }
1934 
1935  /* validate audio service type / channels combination */
1937  avctx->channels == 1) ||
1941  && avctx->channels > 1)) {
1942  av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
1943  "specified number of channels\n");
1944  return AVERROR(EINVAL);
1945  }
1946 
1947  /* validate extended bsi 2 / info metadata */
1948  if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
1949  /* default dolby headphone mode */
1952  /* default dolby surround ex mode */
1955  /* default A/D converter type */
1956  if (opt->ad_converter_type == AC3ENC_OPT_NONE)
1958  }
1959 
1960  /* copyright & original defaults */
1961  if (!s->eac3 || opt->eac3_info_metadata) {
1962  /* default copyright */
1963  if (opt->copyright == AC3ENC_OPT_NONE)
1964  opt->copyright = AC3ENC_OPT_OFF;
1965  /* default original */
1966  if (opt->original == AC3ENC_OPT_NONE)
1967  opt->original = AC3ENC_OPT_ON;
1968  }
1969 
1970  /* dolby surround mode default */
1971  if (!s->eac3 || opt->eac3_info_metadata) {
1974  }
1975 
1976  /* validate audio production info */
1977  if (opt->audio_production_info) {
1978  if (opt->mixing_level == AC3ENC_OPT_NONE) {
1979  av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
1980  "room_type is set\n");
1981  return AVERROR(EINVAL);
1982  }
1983  if (opt->mixing_level < 80) {
1984  av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
1985  "80dB and 111dB\n");
1986  return AVERROR(EINVAL);
1987  }
1988  /* default room type */
1989  if (opt->room_type == AC3ENC_OPT_NONE)
1991  }
1992 
1993  /* set bitstream id for alternate bitstream syntax */
1994  if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {
1995  if (s->bitstream_id > 8 && s->bitstream_id < 11) {
1996  static int warn_once = 1;
1997  if (warn_once) {
1998  av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "
1999  "not compatible with reduced samplerates. writing of "
2000  "extended bitstream information will be disabled.\n");
2001  warn_once = 0;
2002  }
2003  } else {
2004  s->bitstream_id = 6;
2005  }
2006  }
2007 
2008  return 0;
2009 }
2010 
2011 
2018 {
2019  int blk, ch;
2020  AC3EncodeContext *s = avctx->priv_data;
2021 
2023  for (ch = 0; ch < s->channels; ch++)
2024  av_freep(&s->planar_samples[ch]);
2025  av_freep(&s->planar_samples);
2026  av_freep(&s->bap_buffer);
2027  av_freep(&s->bap1_buffer);
2030  av_freep(&s->exp_buffer);
2032  av_freep(&s->psd_buffer);
2034  av_freep(&s->mask_buffer);
2035  av_freep(&s->qmant_buffer);
2038  for (blk = 0; blk < s->num_blocks; blk++) {
2039  AC3Block *block = &s->blocks[blk];
2040  av_freep(&block->mdct_coef);
2041  av_freep(&block->fixed_coef);
2042  av_freep(&block->exp);
2043  av_freep(&block->grouped_exp);
2044  av_freep(&block->psd);
2045  av_freep(&block->band_psd);
2046  av_freep(&block->mask);
2047  av_freep(&block->qmant);
2048  av_freep(&block->cpl_coord_exp);
2049  av_freep(&block->cpl_coord_mant);
2050  }
2051 
2052  s->mdct_end(s);
2053 
2054  return 0;
2055 }
2056 
2057 
2058 /*
2059  * Set channel information during initialization.
2060  */
2061 static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
2062  uint64_t *channel_layout)
2063 {
2064  int ch_layout;
2065 
2066  if (channels < 1 || channels > AC3_MAX_CHANNELS)
2067  return AVERROR(EINVAL);
2068  if (*channel_layout > 0x7FF)
2069  return AVERROR(EINVAL);
2070  ch_layout = *channel_layout;
2071  if (!ch_layout)
2072  ch_layout = av_get_default_channel_layout(channels);
2073 
2074  s->lfe_on = !!(ch_layout & AV_CH_LOW_FREQUENCY);
2075  s->channels = channels;
2076  s->fbw_channels = channels - s->lfe_on;
2077  s->lfe_channel = s->lfe_on ? s->fbw_channels + 1 : -1;
2078  if (s->lfe_on)
2079  ch_layout -= AV_CH_LOW_FREQUENCY;
2080 
2081  switch (ch_layout) {
2083  case AV_CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;
2084  case AV_CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;
2085  case AV_CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;
2086  case AV_CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;
2087  case AV_CH_LAYOUT_QUAD:
2088  case AV_CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;
2089  case AV_CH_LAYOUT_5POINT0:
2090  case AV_CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;
2091  default:
2092  return AVERROR(EINVAL);
2093  }
2094  s->has_center = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
2095  s->has_surround = s->channel_mode & 0x04;
2096 
2098  *channel_layout = ch_layout;
2099  if (s->lfe_on)
2100  *channel_layout |= AV_CH_LOW_FREQUENCY;
2101 
2102  return 0;
2103 }
2104 
2105 
2107 {
2108  AVCodecContext *avctx = s->avctx;
2109  int i, ret, max_sr;
2110 
2111  /* validate channel layout */
2112  if (!avctx->channel_layout) {
2113  av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "
2114  "encoder will guess the layout, but it "
2115  "might be incorrect.\n");
2116  }
2117  ret = set_channel_info(s, avctx->channels, &avctx->channel_layout);
2118  if (ret) {
2119  av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");
2120  return ret;
2121  }
2122 
2123  /* validate sample rate */
2124  /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a
2125  decoder that supports half sample rate so we can validate that
2126  the generated files are correct. */
2127  max_sr = s->eac3 ? 2 : 8;
2128  for (i = 0; i <= max_sr; i++) {
2129  if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)
2130  break;
2131  }
2132  if (i > max_sr) {
2133  av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
2134  return AVERROR(EINVAL);
2135  }
2136  s->sample_rate = avctx->sample_rate;
2137  s->bit_alloc.sr_shift = i / 3;
2138  s->bit_alloc.sr_code = i % 3;
2139  s->bitstream_id = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;
2140 
2141  /* select a default bit rate if not set by the user */
2142  if (!avctx->bit_rate) {
2143  switch (s->fbw_channels) {
2144  case 1: avctx->bit_rate = 96000; break;
2145  case 2: avctx->bit_rate = 192000; break;
2146  case 3: avctx->bit_rate = 320000; break;
2147  case 4: avctx->bit_rate = 384000; break;
2148  case 5: avctx->bit_rate = 448000; break;
2149  }
2150  }
2151 
2152  /* validate bit rate */
2153  if (s->eac3) {
2154  int max_br, min_br, wpf, min_br_dist, min_br_code;
2155  int num_blks_code, num_blocks, frame_samples;
2156 
2157  /* calculate min/max bitrate */
2158  /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
2159  found use either 6 blocks or 1 block, even though 2 or 3 blocks
2160  would work as far as the bit rate is concerned. */
2161  for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
2162  num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
2163  frame_samples = AC3_BLOCK_SIZE * num_blocks;
2164  max_br = 2048 * s->sample_rate / frame_samples * 16;
2165  min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
2166  if (avctx->bit_rate <= max_br)
2167  break;
2168  }
2169  if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
2170  av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
2171  "for this sample rate\n", min_br, max_br);
2172  return AVERROR(EINVAL);
2173  }
2174  s->num_blks_code = num_blks_code;
2175  s->num_blocks = num_blocks;
2176 
2177  /* calculate words-per-frame for the selected bitrate */
2178  wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
2179  av_assert1(wpf > 0 && wpf <= 2048);
2180 
2181  /* find the closest AC-3 bitrate code to the selected bitrate.
2182  this is needed for lookup tables for bandwidth and coupling
2183  parameter selection */
2184  min_br_code = -1;
2185  min_br_dist = INT_MAX;
2186  for (i = 0; i < 19; i++) {
2187  int br_dist = abs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
2188  if (br_dist < min_br_dist) {
2189  min_br_dist = br_dist;
2190  min_br_code = i;
2191  }
2192  }
2193 
2194  /* make sure the minimum frame size is below the average frame size */
2195  s->frame_size_code = min_br_code << 1;
2196  while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
2197  wpf--;
2198  s->frame_size_min = 2 * wpf;
2199  } else {
2200  int best_br = 0, best_code = 0, best_diff = INT_MAX;
2201  for (i = 0; i < 19; i++) {
2202  int br = (ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift) * 1000;
2203  int diff = abs(br - avctx->bit_rate);
2204  if (diff < best_diff) {
2205  best_br = br;
2206  best_code = i;
2207  best_diff = diff;
2208  }
2209  if (!best_diff)
2210  break;
2211  }
2212  avctx->bit_rate = best_br;
2213  s->frame_size_code = best_code << 1;
2215  s->num_blks_code = 0x3;
2216  s->num_blocks = 6;
2217  }
2218  s->bit_rate = avctx->bit_rate;
2219  s->frame_size = s->frame_size_min;
2220 
2221  /* validate cutoff */
2222  if (avctx->cutoff < 0) {
2223  av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
2224  return AVERROR(EINVAL);
2225  }
2226  s->cutoff = avctx->cutoff;
2227  if (s->cutoff > (s->sample_rate >> 1))
2228  s->cutoff = s->sample_rate >> 1;
2229 
2230  ret = ff_ac3_validate_metadata(s);
2231  if (ret)
2232  return ret;
2233 
2236 
2239 
2240  return 0;
2241 }
2242 
2243 
2244 /*
2245  * Set bandwidth for all channels.
2246  * The user can optionally supply a cutoff frequency. Otherwise an appropriate
2247  * default value will be used.
2248  */
2250 {
2251  int blk, ch, cpl_start;
2252 
2253  if (s->cutoff) {
2254  /* calculate bandwidth based on user-specified cutoff frequency */
2255  int fbw_coeffs;
2256  fbw_coeffs = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
2257  s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
2258  } else {
2259  /* use default bandwidth setting */
2260  s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
2261  }
2262 
2263  /* set number of coefficients for each channel */
2264  for (ch = 1; ch <= s->fbw_channels; ch++) {
2265  s->start_freq[ch] = 0;
2266  for (blk = 0; blk < s->num_blocks; blk++)
2267  s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
2268  }
2269  /* LFE channel always has 7 coefs */
2270  if (s->lfe_on) {
2271  s->start_freq[s->lfe_channel] = 0;
2272  for (blk = 0; blk < s->num_blocks; blk++)
2273  s->blocks[blk].end_freq[ch] = 7;
2274  }
2275 
2276  /* initialize coupling strategy */
2277  if (s->cpl_enabled) {
2278  if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
2279  cpl_start = s->options.cpl_start;
2280  } else {
2281  cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
2282  if (cpl_start < 0) {
2284  s->cpl_enabled = 0;
2285  else
2286  cpl_start = 15;
2287  }
2288  }
2289  }
2290  if (s->cpl_enabled) {
2291  int i, cpl_start_band, cpl_end_band;
2292  uint8_t *cpl_band_sizes = s->cpl_band_sizes;
2293 
2294  cpl_end_band = s->bandwidth_code / 4 + 3;
2295  cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
2296 
2297  s->num_cpl_subbands = cpl_end_band - cpl_start_band;
2298 
2299  s->num_cpl_bands = 1;
2300  *cpl_band_sizes = 12;
2301  for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
2303  *cpl_band_sizes += 12;
2304  } else {
2305  s->num_cpl_bands++;
2306  cpl_band_sizes++;
2307  *cpl_band_sizes = 12;
2308  }
2309  }
2310 
2311  s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
2312  s->cpl_end_freq = cpl_end_band * 12 + 37;
2313  for (blk = 0; blk < s->num_blocks; blk++)
2314  s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
2315  }
2316 }
2317 
2318 
2320 {
2321  AVCodecContext *avctx = s->avctx;
2322  int blk, ch;
2323  int channels = s->channels + 1; /* includes coupling channel */
2324  int channel_blocks = channels * s->num_blocks;
2325  int total_coefs = AC3_MAX_COEFS * channel_blocks;
2326 
2327  if (s->allocate_sample_buffers(s))
2328  goto alloc_fail;
2329 
2330  FF_ALLOC_OR_GOTO(avctx, s->bap_buffer, total_coefs *
2331  sizeof(*s->bap_buffer), alloc_fail);
2332  FF_ALLOC_OR_GOTO(avctx, s->bap1_buffer, total_coefs *
2333  sizeof(*s->bap1_buffer), alloc_fail);
2334  FF_ALLOCZ_OR_GOTO(avctx, s->mdct_coef_buffer, total_coefs *
2335  sizeof(*s->mdct_coef_buffer), alloc_fail);
2336  FF_ALLOC_OR_GOTO(avctx, s->exp_buffer, total_coefs *
2337  sizeof(*s->exp_buffer), alloc_fail);
2338  FF_ALLOC_OR_GOTO(avctx, s->grouped_exp_buffer, channel_blocks * 128 *
2339  sizeof(*s->grouped_exp_buffer), alloc_fail);
2340  FF_ALLOC_OR_GOTO(avctx, s->psd_buffer, total_coefs *
2341  sizeof(*s->psd_buffer), alloc_fail);
2342  FF_ALLOC_OR_GOTO(avctx, s->band_psd_buffer, channel_blocks * 64 *
2343  sizeof(*s->band_psd_buffer), alloc_fail);
2344  FF_ALLOC_OR_GOTO(avctx, s->mask_buffer, channel_blocks * 64 *
2345  sizeof(*s->mask_buffer), alloc_fail);
2346  FF_ALLOC_OR_GOTO(avctx, s->qmant_buffer, total_coefs *
2347  sizeof(*s->qmant_buffer), alloc_fail);
2348  if (s->cpl_enabled) {
2349  FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_exp_buffer, channel_blocks * 16 *
2350  sizeof(*s->cpl_coord_exp_buffer), alloc_fail);
2351  FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_mant_buffer, channel_blocks * 16 *
2352  sizeof(*s->cpl_coord_mant_buffer), alloc_fail);
2353  }
2354  for (blk = 0; blk < s->num_blocks; blk++) {
2355  AC3Block *block = &s->blocks[blk];
2356  FF_ALLOCZ_OR_GOTO(avctx, block->mdct_coef, channels * sizeof(*block->mdct_coef),
2357  alloc_fail);
2358  FF_ALLOCZ_OR_GOTO(avctx, block->exp, channels * sizeof(*block->exp),
2359  alloc_fail);
2360  FF_ALLOCZ_OR_GOTO(avctx, block->grouped_exp, channels * sizeof(*block->grouped_exp),
2361  alloc_fail);
2362  FF_ALLOCZ_OR_GOTO(avctx, block->psd, channels * sizeof(*block->psd),
2363  alloc_fail);
2364  FF_ALLOCZ_OR_GOTO(avctx, block->band_psd, channels * sizeof(*block->band_psd),
2365  alloc_fail);
2366  FF_ALLOCZ_OR_GOTO(avctx, block->mask, channels * sizeof(*block->mask),
2367  alloc_fail);
2368  FF_ALLOCZ_OR_GOTO(avctx, block->qmant, channels * sizeof(*block->qmant),
2369  alloc_fail);
2370  if (s->cpl_enabled) {
2371  FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_exp, channels * sizeof(*block->cpl_coord_exp),
2372  alloc_fail);
2373  FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_mant, channels * sizeof(*block->cpl_coord_mant),
2374  alloc_fail);
2375  }
2376 
2377  for (ch = 0; ch < channels; ch++) {
2378  /* arrangement: block, channel, coeff */
2379  block->grouped_exp[ch] = &s->grouped_exp_buffer[128 * (blk * channels + ch)];
2380  block->psd[ch] = &s->psd_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2381  block->band_psd[ch] = &s->band_psd_buffer [64 * (blk * channels + ch)];
2382  block->mask[ch] = &s->mask_buffer [64 * (blk * channels + ch)];
2383  block->qmant[ch] = &s->qmant_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2384  if (s->cpl_enabled) {
2385  block->cpl_coord_exp[ch] = &s->cpl_coord_exp_buffer [16 * (blk * channels + ch)];
2386  block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16 * (blk * channels + ch)];
2387  }
2388 
2389  /* arrangement: channel, block, coeff */
2390  block->exp[ch] = &s->exp_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2391  block->mdct_coef[ch] = &s->mdct_coef_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2392  }
2393  }
2394 
2395  if (!s->fixed_point) {
2396  FF_ALLOCZ_OR_GOTO(avctx, s->fixed_coef_buffer, total_coefs *
2397  sizeof(*s->fixed_coef_buffer), alloc_fail);
2398  for (blk = 0; blk < s->num_blocks; blk++) {
2399  AC3Block *block = &s->blocks[blk];
2400  FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
2401  sizeof(*block->fixed_coef), alloc_fail);
2402  for (ch = 0; ch < channels; ch++)
2403  block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2404  }
2405  } else {
2406  for (blk = 0; blk < s->num_blocks; blk++) {
2407  AC3Block *block = &s->blocks[blk];
2408  FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
2409  sizeof(*block->fixed_coef), alloc_fail);
2410  for (ch = 0; ch < channels; ch++)
2411  block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
2412  }
2413  }
2414 
2415  return 0;
2416 alloc_fail:
2417  return AVERROR(ENOMEM);
2418 }
2419 
2420 
2422 {
2423  AC3EncodeContext *s = avctx->priv_data;
2424  int ret, frame_size_58;
2425 
2426  s->avctx = avctx;
2427 
2428  s->eac3 = avctx->codec_id == AV_CODEC_ID_EAC3;
2429 
2431 
2432  ret = validate_options(s);
2433  if (ret)
2434  return ret;
2435 
2436  avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
2437  avctx->delay = AC3_BLOCK_SIZE;
2438 
2439  s->bitstream_mode = avctx->audio_service_type;
2441  s->bitstream_mode = 0x7;
2442 
2443  s->bits_written = 0;
2444  s->samples_written = 0;
2445 
2446  /* calculate crc_inv for both possible frame sizes */
2447  frame_size_58 = (( s->frame_size >> 2) + ( s->frame_size >> 4)) << 1;
2448  s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2449  if (s->bit_alloc.sr_code == 1) {
2450  frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
2451  s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2452  }
2453 
2454  /* set function pointers */
2459  } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {
2463  }
2464  if (CONFIG_EAC3_ENCODER && s->eac3)
2466  else
2468 
2469  set_bandwidth(s);
2470 
2471  exponent_init(s);
2472 
2473  bit_alloc_init(s);
2474 
2475  ret = s->mdct_init(s);
2476  if (ret)
2477  goto init_fail;
2478 
2479  ret = allocate_buffers(s);
2480  if (ret)
2481  goto init_fail;
2482 
2483  ff_dsputil_init(&s->dsp, avctx);
2486 
2487  dprint_options(s);
2488 
2489  return 0;
2490 init_fail:
2491  ff_ac3_encode_close(avctx);
2492  return ret;
2493 }
#define CONFIG_EAC3_ENCODER
Definition: config.h:931
static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
Initialize mantissa counts.
Definition: ac3enc.c:993
uint64_t av_get_default_channel_layout(int nb_channels)
Return default channel layout for a given number of channels.
uint8_t new_rematrixing_strategy
send new rematrixing flags in this block
Definition: ac3enc.h:140
uint8_t exp_strategy[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]
exponent strategies
Definition: ac3enc.h:245
uint32_t poly
Definition: crc.c:217
int eac3_mixing_metadata
Definition: ac3enc.h:115
const uint8_t ff_ac3_bap_tab[64]
Definition: ac3tab.c:268
#define CONFIG_AC3_ENCODER
Definition: config.h:928
av_cold void ff_dsputil_init(DSPContext *c, AVCodecContext *avctx)
Definition: dsputil.c:2440
#define AC3_MAX_CODED_FRAME_SIZE
Definition: ac3.h:30
int dialogue_level
Definition: ac3enc.h:95
static av_cold int set_channel_info(AC3EncodeContext *s, int channels, uint64_t *channel_layout)
Definition: ac3enc.c:2061
static void ac3_output_frame_header(AC3EncodeContext *s)
Definition: ac3enc.c:1329
int db_per_bit_code
dB/bit code (dbpbcod)
Definition: ac3enc.h:220
static const uint8_t exp_strategy_reuse_tab[4][6]
Table used to select exponent strategy based on exponent reuse block interval.
Definition: ac3enc.c:344
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:275
int slow_decay_code
slow decay code (sdcycod)
Definition: ac3enc.h:218
Encoding Options used by AVOption.
Definition: ac3enc.h:93
const uint8_t ff_ac3_slow_decay_tab[4]
Definition: ac3tab.c:278
int ff_ac3_fixed_allocate_sample_buffers(AC3EncodeContext *s)
float loro_surround_mix_level
Definition: ac3enc.h:110
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:177
static void compute_exp_strategy(AC3EncodeContext *s)
Definition: ac3enc.c:355
int channel_coupling
Definition: ac3enc.h:121
static int asym_quant(int c, int e, int qbits)
Asymmetric quantization on 2^qbits levels.
Definition: ac3enc.c:1179
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
int dolby_surround_ex_mode
Definition: ac3enc.h:112
static uint8_t exponent_group_tab[2][3][256]
LUT for number of exponent groups.
Definition: ac3enc.c:72
#define AV_CH_LAYOUT_SURROUND
uint8_t ** cpl_coord_exp
coupling coord exponents (cplcoexp)
Definition: ac3enc.h:137
#define AC3_MAX_COEFS
Definition: ac3.h:34
int bandwidth_code
bandwidth code (0 to 60) (chbwcod)
Definition: ac3enc.h:204
const uint16_t ff_ac3_frame_size_tab[38][3]
Possible frame sizes.
Definition: ac3tab.c:35
uint8_t * grouped_exp_buffer
Definition: ac3enc.h:237
static av_cold int allocate_buffers(AC3EncodeContext *s)
Definition: ac3enc.c:2319
av_cold void ff_ac3_common_init(void)
Initialize some tables.
Definition: ac3.c:220
#define LEVEL_PLUS_1POINT5DB
Definition: ac3.h:54
int16_t ** psd
psd per frequency bin
Definition: ac3enc.h:133
int frame_size_code
frame size code (frmsizecod)
Definition: ac3enc.h:182
void(* mdct_end)(struct AC3EncodeContext *s)
Definition: ac3enc.h:253
int frame_bits
all frame bits except exponents and mantissas
Definition: ac3enc.h:227
#define av_bswap16
Definition: bswap.h:31
void ff_ac3_process_exponents(AC3EncodeContext *s)
Calculate final exponents from the supplied MDCT coefficients and exponent shift. ...
Definition: ac3enc.c:634
#define EXP_REUSE
Definition: ac3.h:45
const uint16_t ff_ac3_sample_rate_tab[3]
Definition: ac3tab.c:127
#define AV_CH_LAYOUT_4POINT0
uint8_t ** cpl_coord_mant
coupling coord mantissas (cplcomant)
Definition: ac3enc.h:138
uint16_t ** qmant
quantized mantissas
Definition: ac3enc.h:136
av_dlog(ac->avr,"%d samples - audio_convert: %s to %s (%s)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic?ac->func_descr_generic:ac->func_descr)
int start_freq[AC3_MAX_CHANNELS]
start frequency bin (strtmant)
Definition: ac3enc.h:205
#define AV_CH_LAYOUT_STEREO
const uint16_t ff_ac3_slow_gain_tab[4]
Definition: ac3tab.c:286
PutBitContext pb
bitstream writer context
Definition: ac3enc.h:161
#define blk(i)
Definition: sha.c:173
#define EXP_D25
Definition: ac3.h:49
static const float cmixlev_options[CMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:52
int num_cpl_channels
number of channels in coupling
Definition: ac3enc.h:146
AC3BitAllocParameters bit_alloc
bit allocation parameters
Definition: ac3enc.h:222
#define AV_CH_LAYOUT_5POINT0
static int count_exponent_bits(AC3EncodeContext *s)
Definition: ac3enc.c:544
static void extract_exponents(AC3EncodeContext *s)
Definition: ac3enc.c:325
Macro definitions for various function/variable attributes.
int ff_ac3_float_allocate_sample_buffers(AC3EncodeContext *s)
DSPContext dsp
Definition: ac3enc.h:162
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1854
int ff_ac3_validate_metadata(AC3EncodeContext *s)
Validate metadata options as set by AVOption system.
Definition: ac3enc.c:1833
float ltrt_surround_mix_level
Definition: ac3enc.h:108
int new_cpl_leak
send new coupling leak info
Definition: ac3enc.h:150
int rematrixing_enabled
stereo rematrixing enabled
Definition: ac3enc.h:214
void ff_eac3_get_frame_exp_strategy(AC3EncodeContext *s)
Determine frame exponent strategy use and indices.
Definition: eac3enc.c:64
int channel_mode
channel mode (acmod)
Definition: ac3enc.h:193
int num_cpl_subbands
number of coupling subbands (ncplsubnd)
Definition: ac3enc.h:210
float surround_mix_level
Definition: ac3enc.h:98
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1787
uint8_t
int(* allocate_sample_buffers)(struct AC3EncodeContext *s)
Definition: ac3enc.h:257
#define av_cold
Definition: attributes.h:66
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:63
static void count_frame_bits(AC3EncodeContext *s)
Definition: ac3enc.c:792
AVOptions.
static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:62
uint8_t rematrixing_flags[4]
rematrixing flags
Definition: ac3enc.h:142
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:261
#define EXP_D15
Definition: ac3.h:48
int fbw_channels
number of full-bandwidth channels (nfchans)
Definition: ac3enc.h:187
uint8_t new_cpl_coords[AC3_MAX_CHANNELS]
send new coupling coordinates (cplcoe)
Definition: ac3enc.h:147
static av_cold void set_bandwidth(AC3EncodeContext *s)
Definition: ac3enc.c:2249
#define b
Definition: input.c:52
const uint8_t ff_ac3_enc_channel_map[8][2][6]
Table to remap channels from SMPTE order to AC-3 order.
Definition: ac3tab.c:110
#define emms_c()
Definition: internal.h:46
av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
Finalize encoding and free any memory allocated by the encoder.
Definition: ac3enc.c:2017
uint8_t * bap1_buffer
Definition: ac3enc.h:233
#define AV_CH_LOW_FREQUENCY
int slow_gain_code
slow gain code (sgaincod)
Definition: ac3enc.h:217
uint8_t cpl_master_exp[AC3_MAX_CHANNELS]
coupling coord master exponents (mstrcplco)
Definition: ac3enc.h:148
static int flags
Definition: log.c:44
#define CRC16_POLY
CRC-16 Polynomial.
Definition: ac3enc.c:1575
uint8_t ** exp
original exponents
Definition: ac3enc.h:131
#define CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition: avcodec.h:685
int num_rematrixing_bands
number of rematrixing bands
Definition: ac3enc.h:141
static av_cold int validate_options(AC3EncodeContext *s)
Definition: ac3enc.c:2106
AC3DSPContext ac3dsp
AC-3 optimized functions.
Definition: ac3enc.h:164
int loro_center_mix_level
Lo/Ro center mix level code.
Definition: ac3enc.h:200
int num_cpl_bands
number of coupling bands (ncplbnd)
Definition: ac3enc.h:211
static int bit_alloc(AC3EncodeContext *s, int snr_offset)
Run the bit allocation with a given SNR offset.
Definition: ac3enc.c:1061
void ff_ac3_fixed_mdct_end(AC3EncodeContext *s)
static void dprint_options(AC3EncodeContext *s)
Definition: ac3enc.c:1676
int lfe_channel
channel index of the LFE channel
Definition: ac3enc.h:190
int mant2_cnt
Definition: ac3enc.c:48
#define CONFIG_AC3_FIXED_ENCODER
Definition: config.h:929
int ref_bap_set
indicates if ref_bap pointers have been set
Definition: ac3enc.h:250
#define EXP_DIFF_THRESHOLD
Exponent Difference Threshold.
Definition: ac3enc.c:339
static av_cold void exponent_init(AC3EncodeContext *s)
Definition: ac3enc.c:303
static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef, uint8_t *exp, uint8_t *bap, int16_t *qmant, int start_freq, int end_freq)
Quantize a set of mantissas for a single channel in a single block.
Definition: ac3enc.c:1203
int new_snr_offsets
send new SNR offsets
Definition: ac3enc.h:149
#define r
Definition: input.c:51
int loro_surround_mix_level
Lo/Ro surround mix level code.
Definition: ac3enc.h:201
CoefType ** mdct_coef
MDCT coefficients.
Definition: ac3enc.h:129
int16_t * qmant4_ptr
mantissa pointers for bap=1,2,4
Definition: ac3enc.c:47
#define AV_CH_LAYOUT_5POINT1
uint8_t channel_in_cpl[AC3_MAX_CHANNELS]
channel in coupling (chincpl)
Definition: ac3enc.h:145
int16_t * qmant1_ptr
Definition: ac3enc.c:47
int eac3_info_metadata
Definition: ac3enc.h:116
int mixing_level
Definition: ac3enc.h:101
#define AC3ENC_OPT_SMALL_ROOM
Definition: ac3enc.h:83
int num_blks_code
number of blocks code (numblkscod)
Definition: ac3enc.h:178
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
const uint64_t ff_ac3_channel_layouts[19]
List of supported channel layouts.
Definition: ac3enc.c:78
static uint8_t * put_bits_ptr(PutBitContext *s)
Return the pointer to the byte where the bitstream writer will put the next bit.
Definition: put_bits.h:204
static int sym_quant(int c, int e, int levels)
Symmetric quantization on 'levels' levels.
Definition: ac3enc.c:1163
const uint8_t ff_ac3_fast_decay_tab[4]
Definition: ac3tab.c:282
AC3EncOptions options
encoding options
Definition: ac3enc.h:159
int16_t ** band_psd
psd per critical band
Definition: ac3enc.h:134
float ltrt_center_mix_level
Definition: ac3enc.h:107
#define AVERROR(e)
Definition: error.h:43
static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy, int cpl)
Update the exponents so that they are the ones the decoder will decode.
Definition: ac3enc.c:421
int channels
total number of channels (nchans)
Definition: ac3enc.h:188
#define AC3_MAX_CHANNELS
maximum number of channels, including coupling channel
Definition: ac3.h:31
int flags
CODEC_FLAG_*.
Definition: avcodec.h:1142
int ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *band_psd, int start, int end, int fast_gain, int is_lfe, int dba_mode, int dba_nsegs, uint8_t *dba_offsets, uint8_t *dba_lengths, uint8_t *dba_values, int16_t *mask)
Calculate the masking curve.
Definition: ac3.c:123
uint8_t * buf
Definition: put_bits.h:43
uint16_t crc_inv[2]
Definition: ac3enc.h:183
int cpl_on
coupling turned on for this frame
Definition: ac3enc.h:208
simple assert() macros that are a bit more flexible than ISO C assert().
#define AV_CH_LAYOUT_QUAD
int16_t * mask_buffer
Definition: ac3enc.h:240
int16_t * psd_buffer
Definition: ac3enc.h:238
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:148
int fixed_point
indicates if fixed-point encoder is being used
Definition: ac3enc.h:170
int ltrt_surround_mix_level
Lt/Rt surround mix level code.
Definition: ac3enc.h:199
static void put_bits(PutBitContext *s, int n, unsigned int value)
Write up to 31 bits into a bitstream.
Definition: put_bits.h:139
int new_cpl_strategy
send new coupling strategy
Definition: ac3enc.h:143
int surround_mix_level
surround mix level code
Definition: ac3enc.h:197
#define LEVEL_MINUS_3DB
Definition: ac3.h:56
int cpl_in_use
coupling in use for this block (cplinu)
Definition: ac3enc.h:144
size_t av_strlcpy(char *dst, const char *src, size_t size)
Copy the string src to dst, but no more than size - 1 bytes, and null-terminate dst.
Definition: avstring.c:81
int cpl_enabled
coupling enabled for all frames
Definition: ac3enc.h:209
static void output_frame_end(AC3EncodeContext *s)
Definition: ac3enc.c:1612
#define EXTMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:61
Definition: ac3enc.c:46
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1840
#define LEVEL_MINUS_4POINT5DB
Definition: ac3.h:57
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:72
#define AC3_BLOCK_SIZE
Definition: ac3.h:35
static void output_audio_block(AC3EncodeContext *s, int blk)
Definition: ac3enc.c:1385
const uint16_t ff_ac3_bitrate_tab[19]
Definition: ac3tab.c:130
static int count_mantissa_bits(AC3EncodeContext *s)
Definition: ac3enc.c:1035
#define AV_CH_LAYOUT_2_1
#define AV_CH_LAYOUT_2_2
Data for a single audio block.
Definition: ac3enc.h:128
#define AC3ENC_OPT_ON
Definition: ac3enc.h:76
common internal API header
int(* mdct_init)(struct AC3EncodeContext *s)
Definition: ac3enc.h:254
int floor_code
floor code (floorcod)
Definition: ac3enc.h:221
int ff_ac3_compute_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1143
#define AC3ENC_OPT_DOWNMIX_LORO
Definition: ac3enc.h:85
int bitstream_mode
bitstream mode (bsmod)
Definition: ac3enc.h:173
#define AC3ENC_OPT_ADCONV_STANDARD
Definition: ac3enc.h:86
int has_surround
indicates if there are one or more surround channels
Definition: ac3enc.h:192
int bit_rate
the average bitrate
Definition: avcodec.h:1112
audio channel layout utility functions
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
#define FFMIN(a, b)
Definition: common.h:57
int eac3
indicates if this is E-AC-3 vs. AC-3
Definition: ac3enc.h:171
static const uint8_t ac3_bandwidth_tab[5][3][19]
LUT to select the bandwidth code based on the bit rate, sample rate, and number of full-bandwidth cha...
Definition: ac3enc.c:106
float loro_center_mix_level
Definition: ac3enc.h:109
av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
Definition: ac3dsp.c:213
int mant4_cnt
mantissa counts for bap=1,2,4
Definition: ac3enc.c:48
int ff_ac3_float_mdct_init(AC3EncodeContext *s)
Initialize MDCT tables.
Definition: ac3enc_float.c:64
int32_t
const uint16_t ff_ac3_fast_gain_tab[8]
Definition: ac3tab.c:298
int ad_converter_type
Definition: ac3enc.h:114
void ff_ac3_adjust_frame_size(AC3EncodeContext *s)
Adjust the frame size to make the average bit rate match the target bit rate.
Definition: ac3enc.c:180
#define AC3ENC_OPT_AUTO
Definition: ac3enc.h:74
int exponent_bits
number of bits used for exponents
Definition: ac3enc.h:228
int stereo_rematrixing
Definition: ac3enc.h:120
#define AV_CH_LAYOUT_5POINT1_BACK
int coarse_snr_offset
coarse SNR offsets (csnroffst)
Definition: ac3enc.h:223
Definition: ac3.h:67
const char * av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
Definition: samplefmt.c:47
int16_t ** mask
masking curve
Definition: ac3enc.h:135
void(* extract_exponents)(uint8_t *exp, int32_t *coef, int nb_coefs)
Definition: ac3dsp.h:127
AVFloatDSPContext fdsp
Definition: ac3enc.h:163
if(ac->has_optimized_func)
SampleType ** planar_samples
Definition: ac3enc.h:231
int fast_decay_code
fast decay code (fdcycod)
Definition: ac3enc.h:219
int16_t * qmant_buffer
Definition: ac3enc.h:241
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1799
#define AC3ENC_OPT_MODE_OFF
Definition: ac3enc.h:79
void(* bit_alloc_calc_bap)(int16_t *mask, int16_t *psd, int start, int end, int snr_offset, int floor, const uint8_t *bap_tab, uint8_t *bap)
Calculate bit allocation pointers.
Definition: ac3dsp.h:106
NULL
Definition: eval.c:55
#define AC3ENC_OPT_ADCONV_HDCD
Definition: ac3enc.h:87
void(* output_frame_header)(struct AC3EncodeContext *s)
Definition: ac3enc.h:260
#define CPL_CH
coupling channel index
Definition: ac3.h:32
const uint8_t ff_eac3_default_cpl_band_struct[18]
Table E2.16 Default Coupling Banding Structure.
Definition: ac3tab.c:144
uint8_t * ref_bap[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]
bit allocation pointers (bap)
Definition: ac3enc.h:249
void ff_eac3_output_frame_header(AC3EncodeContext *s)
Write the E-AC-3 frame header to the output bitstream.
Definition: eac3enc.c:124
Libavcodec external API header.
int audio_production_info
Definition: ac3enc.h:100
enum AVCodecID codec_id
Definition: avcodec.h:1065
int sample_rate
samples per second
Definition: avcodec.h:1779
int dolby_surround_mode
Definition: ac3enc.h:99
static const int8_t ac3_coupling_start_tab[6][3][19]
LUT to select the coupling start band based on the bit rate, sample rate, and number of full-bandwidt...
Definition: ac3enc.c:139
main external API structure.
Definition: avcodec.h:1054
int fast_gain_code[AC3_MAX_CHANNELS]
fast gain codes (signal-to-mask ratio) (fgaincod)
Definition: ac3enc.h:224
int sample_rate
sampling frequency, in Hz
Definition: ac3enc.h:176
CoefType * mdct_coef_buffer
Definition: ac3enc.h:234
#define LEVEL_ZERO
Definition: ac3.h:60
#define LEVEL_ONE
Definition: ac3.h:61
int has_center
indicates if there is a center channel
Definition: ac3enc.h:191
int bit_rate
target bit rate, in bits-per-second
Definition: ac3enc.h:175
static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
Definition: ac3enc.c:1578
const uint8_t * channel_map
channel map used to reorder channels
Definition: ac3enc.h:194
uint8_t * exp_buffer
Definition: ac3enc.h:236
int frame_bits_fixed
number of non-coefficient bits for fixed parameters
Definition: ac3enc.h:226
int end_freq[AC3_MAX_CHANNELS]
end frequency bin (endmant)
Definition: ac3enc.h:151
#define FLT_OPTION_THRESHOLD
Definition: ac3enc.c:1791
static int validate_float_option(float v, const float *v_list, int v_list_size)
Definition: ac3enc.c:1793
int cpl_start
Definition: ac3enc.h:122
uint8_t * cpl_coord_exp_buffer
Definition: ac3enc.h:242
int ltrt_center_mix_level
Lt/Rt center mix level code.
Definition: ac3enc.h:198
#define AV_WB16(p, d)
Definition: intreadwrite.h:213
#define AV_CH_LAYOUT_5POINT0_BACK
av_cold void ff_eac3_exponent_init(void)
Initialize E-AC-3 exponent tables.
Definition: eac3enc.c:48
int center_mix_level
center mix level code
Definition: ac3enc.h:196
#define AC3_MAX_BLOCKS
Definition: ac3.h:36
AC-3 encoder private context.
Definition: ac3enc.h:157
void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
Write the frame to the output bitstream.
Definition: ac3enc.c:1661
static void count_frame_bits_fixed(AC3EncodeContext *s)
Definition: ac3enc.c:650
AC3Block blocks[AC3_MAX_BLOCKS]
per-block info
Definition: ac3enc.h:168
const int16_t ff_ac3_floor_tab[8]
Definition: ac3tab.c:294
SampleType * windowed_samples
Definition: ac3enc.h:230
int mant1_cnt
Definition: ac3enc.c:48
int preferred_stereo_downmix
Definition: ac3enc.h:106
void ff_ac3_quantize_mantissas(AC3EncodeContext *s)
Quantize mantissas using coefficients, exponents, and bit allocation pointers.
Definition: ac3enc.c:1300
int(* compute_mantissa_size)(uint16_t mant_cnt[6][16])
Calculate the number of bits needed to encode a set of mantissas.
Definition: ac3dsp.h:125
int num_blocks
number of blocks per frame
Definition: ac3enc.h:179
static void encode_exponents(AC3EncodeContext *s)
Definition: ac3enc.c:494
#define CMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:51
av_cold void avpriv_float_dsp_init(AVFloatDSPContext *fdsp, int bit_exact)
Initialize a float DSP context.
Definition: float_dsp.c:115
float center_mix_level
Definition: ac3enc.h:97
#define EXP_NEW
Definition: ac3.h:46
static void reset_block_bap(AC3EncodeContext *s)
Definition: ac3enc.c:968
static av_cold void bit_alloc_init(AC3EncodeContext *s)
Definition: ac3enc.c:756
int extended_bsi_2
Definition: ac3enc.h:111
#define AC3_FRAME_SIZE
Definition: ac3.h:37
int frame_size
current frame size in bytes
Definition: ac3enc.h:181
#define SURMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:56
int room_type
Definition: ac3enc.h:102
void(* update_bap_counts)(uint16_t mant_cnt[16], uint8_t *bap, int len)
Update bap counts using the supplied array of bap.
Definition: ac3dsp.h:117
uint8_t ** grouped_exp
grouped exponents
Definition: ac3enc.h:132
int cpl_end_freq
coupling channel end frequency bin
Definition: ac3enc.h:206
#define AC3ENC_OPT_LARGE_ROOM
Definition: ac3enc.h:82
uint8_t cpl_band_sizes[AC3_MAX_CPL_BANDS]
number of coeffs in each coupling band
Definition: ac3enc.h:212
#define AC3ENC_OPT_MODE_ON
Definition: ac3enc.h:78
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:88
static void validate_mix_level(void *log_ctx, const char *opt_name, float *opt_param, const float *list, int list_size, int default_value, int min_value, int *ctx_param)
Definition: ac3enc.c:1809
#define FF_ALLOC_OR_GOTO(ctx, p, size, label)
Definition: internal.h:109
me_cmp_func sad[6]
Definition: dsputil.h:148
static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:57
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:53
int64_t bits_written
bit count (used to avg. bitrate)
Definition: ac3enc.h:184
uint32_t AVCRC
Definition: crc.h:28
#define AC3ENC_OPT_NONE
Definition: ac3enc.h:73
void(* ac3_exponent_min)(uint8_t *exp, int num_reuse_blocks, int nb_coefs)
Set each encoded exponent in a block to the minimum of itself and the exponents in the same frequency...
Definition: ac3dsp.h:43
int bitstream_id
bitstream id (bsid)
Definition: ac3enc.h:172
int16_t * band_psd_buffer
Definition: ac3enc.h:239
int dolby_headphone_mode
Definition: ac3enc.h:113
AVCodecContext * avctx
parent AVCodecContext
Definition: ac3enc.h:160
uint8_t exp_ref_block[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]
reference blocks for EXP_REUSE
Definition: ac3enc.h:248
void * priv_data
Definition: avcodec.h:1090
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1823
int allow_per_frame_metadata
Definition: ac3enc.h:119
void ff_ac3_bit_alloc_calc_psd(int8_t *exp, int start, int end, int16_t *psd, int16_t *band_psd)
Calculate the log power-spectral density of the input signal.
Definition: ac3.c:97
static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch, uint16_t mant_cnt[AC3_MAX_BLOCKS][16], int start, int end)
Update mantissa bit counts for all blocks in 1 channel in a given bandwidth range.
Definition: ac3enc.c:1015
int original
Definition: ac3enc.h:104
#define LEVEL_PLUS_3DB
Definition: ac3.h:53
#define AC3ENC_OPT_DOWNMIX_LTRT
Definition: ac3enc.h:84
int channels
number of audio channels
Definition: avcodec.h:1780
#define AC3ENC_OPT_NOT_INDICATED
Definition: ac3enc.h:77
static int cbr_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1092
uint8_t * bap_buffer
Definition: ac3enc.h:232
int frame_size_min
minimum frame size in case rounding is necessary
Definition: ac3enc.h:180
#define LEVEL_MINUS_6DB
Definition: ac3.h:58
void ff_ac3_float_mdct_end(AC3EncodeContext *s)
Finalize MDCT and free allocated memory.
Definition: ac3enc_float.c:51
AC-3 encoder & E-AC-3 encoder common header.
static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
Definition: ac3enc.c:1595
#define LOCAL_ALIGNED_16(t, v,...)
Definition: internal.h:106
void ff_ac3_apply_rematrixing(AC3EncodeContext *s)
Apply stereo rematrixing to coefficients based on rematrixing flags.
Definition: ac3enc.c:269
const uint8_t ff_ac3_rematrix_band_tab[5]
Table of bin locations for rematrixing bands reference: Section 7.5.2 Rematrixing : Frequency Band De...
Definition: ac3tab.c:139
int64_t samples_written
sample count (used to avg. bitrate)
Definition: ac3enc.h:185
uint8_t * cpl_coord_mant_buffer
Definition: ac3enc.h:243
int use_frame_exp_strategy
indicates use of frame exp strategy
Definition: ac3enc.h:247
#define FFSWAP(type, a, b)
Definition: common.h:60
static void bit_alloc_masking(AC3EncodeContext *s)
Definition: ac3enc.c:938
int ff_ac3_fixed_mdct_init(AC3EncodeContext *s)
void ff_ac3_group_exponents(AC3EncodeContext *s)
Group exponents.
Definition: ac3enc.c:576
const uint16_t ff_ac3_db_per_bit_tab[4]
Definition: ac3tab.c:290
int16_t * qmant2_ptr
Definition: ac3enc.c:47
#define AV_CH_LAYOUT_MONO
void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
Set the initial coupling strategy parameters prior to coupling analysis.
Definition: ac3enc.c:198
int cutoff
user-specified cutoff frequency, in Hz
Definition: ac3enc.h:203
E-AC-3 encoder.
int lfe_on
indicates if there is an LFE channel (lfeon)
Definition: ac3enc.h:189
int fine_snr_offset[AC3_MAX_CHANNELS]
fine SNR offsets (fsnroffst)
Definition: ac3enc.h:225
#define AC3ENC_OPT_OFF
Definition: ac3enc.h:75
int delay
Codec delay.
Definition: avcodec.h:1205
Common code between the AC-3 encoder and decoder.
int32_t * fixed_coef_buffer
Definition: ac3enc.h:235
#define EXP_D45
Definition: ac3.h:50
#define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)
Definition: internal.h:118
int extended_bsi_1
Definition: ac3enc.h:105
int copyright
Definition: ac3enc.h:103
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
Return a description of a channel layout.
int32_t ** fixed_coef
fixed-point MDCT coefficients
Definition: ac3enc.h:130
av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
Definition: ac3enc.c:2421
bitstream writer API
static int16_t block[64]
Definition: dct-test.c:170