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 //#define ASSERT_LEVEL 2
30 
31 #include <stdint.h>
32 
33 #include "libavutil/avassert.h"
34 #include "libavutil/avstring.h"
36 #include "libavutil/crc.h"
37 #include "libavutil/opt.h"
38 #include "avcodec.h"
39 #include "put_bits.h"
40 #include "dsputil.h"
41 #include "ac3dsp.h"
42 #include "ac3.h"
43 #include "fft.h"
44 #include "ac3enc.h"
45 #include "eac3enc.h"
46 
47 typedef struct AC3Mant {
50 } AC3Mant;
51 
52 #define CMIXLEV_NUM_OPTIONS 3
53 static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
55 };
56 
57 #define SURMIXLEV_NUM_OPTIONS 3
60 };
61 
62 #define EXTMIXLEV_NUM_OPTIONS 8
66 };
67 
68 
73 static uint8_t exponent_group_tab[2][3][256];
74 
75 
79 const uint64_t ff_ac3_channel_layouts[19] = {
90  (AV_CH_LAYOUT_STEREO | AV_CH_LOW_FREQUENCY),
91  (AV_CH_LAYOUT_2_1 | AV_CH_LOW_FREQUENCY),
92  (AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY),
93  (AV_CH_LAYOUT_2_2 | AV_CH_LOW_FREQUENCY),
94  (AV_CH_LAYOUT_QUAD | AV_CH_LOW_FREQUENCY),
95  (AV_CH_LAYOUT_4POINT0 | AV_CH_LOW_FREQUENCY),
98  0
99 };
100 
101 
107 static const uint8_t ac3_bandwidth_tab[5][3][19] = {
108 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
109 
110  { { 0, 0, 0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
111  { 0, 0, 0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
112  { 0, 0, 0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
113 
114  { { 0, 0, 0, 0, 0, 0, 0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
115  { 0, 0, 0, 0, 0, 0, 4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
116  { 0, 0, 0, 0, 0, 0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
117 
118  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
119  { 0, 0, 0, 0, 0, 0, 0, 0, 4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
120  { 0, 0, 0, 0, 0, 0, 0, 0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
121 
122  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
123  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
124  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
125 
126  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 20, 32, 40, 48, 48, 48, 48 },
127  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 36, 44, 56, 56, 56, 56 },
128  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28, 44, 60, 60, 60, 60, 60, 60 } }
129 };
130 
131 
140 static const int8_t ac3_coupling_start_tab[6][3][19] = {
141 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
142 
143  // 2/0
144  { { 0, 0, 0, 0, 0, 0, 0, 1, 1, 7, 8, 11, 12, -1, -1, -1, -1, -1, -1 },
145  { 0, 0, 0, 0, 0, 0, 1, 3, 5, 7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
146  { 0, 0, 0, 0, 1, 2, 2, 9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
147 
148  // 3/0
149  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
150  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
151  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
152 
153  // 2/1 - untested
154  { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
155  { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
156  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
157 
158  // 3/1
159  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
160  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
161  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
162 
163  // 2/2 - untested
164  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
165  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
166  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
167 
168  // 3/2
169  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
170  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
171  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
172 };
173 
174 
182 {
183  while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
184  s->bits_written -= s->bit_rate;
185  s->samples_written -= s->sample_rate;
186  }
187  s->frame_size = s->frame_size_min +
188  2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
189  s->bits_written += s->frame_size * 8;
191 }
192 
193 
200 {
201  int blk, ch;
202  int got_cpl_snr;
203  int num_cpl_blocks;
204 
205  /* set coupling use flags for each block/channel */
206  /* TODO: turn coupling on/off and adjust start band based on bit usage */
207  for (blk = 0; blk < s->num_blocks; blk++) {
208  AC3Block *block = &s->blocks[blk];
209  for (ch = 1; ch <= s->fbw_channels; ch++)
210  block->channel_in_cpl[ch] = s->cpl_on;
211  }
212 
213  /* enable coupling for each block if at least 2 channels have coupling
214  enabled for that block */
215  got_cpl_snr = 0;
216  num_cpl_blocks = 0;
217  for (blk = 0; blk < s->num_blocks; blk++) {
218  AC3Block *block = &s->blocks[blk];
219  block->num_cpl_channels = 0;
220  for (ch = 1; ch <= s->fbw_channels; ch++)
221  block->num_cpl_channels += block->channel_in_cpl[ch];
222  block->cpl_in_use = block->num_cpl_channels > 1;
223  num_cpl_blocks += block->cpl_in_use;
224  if (!block->cpl_in_use) {
225  block->num_cpl_channels = 0;
226  for (ch = 1; ch <= s->fbw_channels; ch++)
227  block->channel_in_cpl[ch] = 0;
228  }
229 
230  block->new_cpl_strategy = !blk;
231  if (blk) {
232  for (ch = 1; ch <= s->fbw_channels; ch++) {
233  if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
234  block->new_cpl_strategy = 1;
235  break;
236  }
237  }
238  }
239  block->new_cpl_leak = block->new_cpl_strategy;
240 
241  if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
242  block->new_snr_offsets = 1;
243  if (block->cpl_in_use)
244  got_cpl_snr = 1;
245  } else {
246  block->new_snr_offsets = 0;
247  }
248  }
249  if (!num_cpl_blocks)
250  s->cpl_on = 0;
251 
252  /* set bandwidth for each channel */
253  for (blk = 0; blk < s->num_blocks; blk++) {
254  AC3Block *block = &s->blocks[blk];
255  for (ch = 1; ch <= s->fbw_channels; ch++) {
256  if (block->channel_in_cpl[ch])
257  block->end_freq[ch] = s->start_freq[CPL_CH];
258  else
259  block->end_freq[ch] = s->bandwidth_code * 3 + 73;
260  }
261  }
262 }
263 
264 
271 {
272  int nb_coefs;
273  int blk, bnd, i;
274  int start, end;
275  uint8_t *flags;
276 
277  if (!s->rematrixing_enabled)
278  return;
279 
280  for (blk = 0; blk < s->num_blocks; blk++) {
281  AC3Block *block = &s->blocks[blk];
282  if (block->new_rematrixing_strategy)
283  flags = block->rematrixing_flags;
284  nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
285  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
286  if (flags[bnd]) {
287  start = ff_ac3_rematrix_band_tab[bnd];
288  end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
289  for (i = start; i < end; i++) {
290  int32_t lt = block->fixed_coef[1][i];
291  int32_t rt = block->fixed_coef[2][i];
292  block->fixed_coef[1][i] = (lt + rt) >> 1;
293  block->fixed_coef[2][i] = (lt - rt) >> 1;
294  }
295  }
296  }
297  }
298 }
299 
300 
301 /*
302  * Initialize exponent tables.
303  */
305 {
306  int expstr, i, grpsize;
307 
308  for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
309  grpsize = 3 << expstr;
310  for (i = 12; i < 256; i++) {
311  exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
312  exponent_group_tab[1][expstr][i] = (i ) / grpsize;
313  }
314  }
315  /* LFE */
316  exponent_group_tab[0][0][7] = 2;
317 
318  if (CONFIG_EAC3_ENCODER && s->eac3)
320 }
321 
322 
323 /*
324  * Extract exponents from the MDCT coefficients.
325  */
327 {
328  int ch = !s->cpl_on;
329  int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
330  AC3Block *block = &s->blocks[0];
331 
332  s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
333 }
334 
335 
340 #define EXP_DIFF_THRESHOLD 500
341 
345 static const uint8_t exp_strategy_reuse_tab[4][6] = {
346  { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
347  { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
348  { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
349  { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 }
350 };
351 
352 /*
353  * Calculate exponent strategies for all channels.
354  * Array arrangement is reversed to simplify the per-channel calculation.
355  */
357 {
358  int ch, blk, blk1;
359 
360  for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
361  uint8_t *exp_strategy = s->exp_strategy[ch];
362  uint8_t *exp = s->blocks[0].exp[ch];
363  int exp_diff;
364 
365  /* estimate if the exponent variation & decide if they should be
366  reused in the next frame */
367  exp_strategy[0] = EXP_NEW;
368  exp += AC3_MAX_COEFS;
369  for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
370  if (ch == CPL_CH) {
371  if (!s->blocks[blk-1].cpl_in_use) {
372  exp_strategy[blk] = EXP_NEW;
373  continue;
374  } else if (!s->blocks[blk].cpl_in_use) {
375  exp_strategy[blk] = EXP_REUSE;
376  continue;
377  }
378  } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
379  exp_strategy[blk] = EXP_NEW;
380  continue;
381  }
382  exp_diff = s->dsp.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
383  exp_strategy[blk] = EXP_REUSE;
384  if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
385  exp_strategy[blk] = EXP_NEW;
386  else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
387  exp_strategy[blk] = EXP_NEW;
388  }
389 
390  /* now select the encoding strategy type : if exponents are often
391  recoded, we use a coarse encoding */
392  blk = 0;
393  while (blk < s->num_blocks) {
394  blk1 = blk + 1;
395  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
396  blk1++;
397  exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
398  blk = blk1;
399  }
400  }
401  if (s->lfe_on) {
402  ch = s->lfe_channel;
403  s->exp_strategy[ch][0] = EXP_D15;
404  for (blk = 1; blk < s->num_blocks; blk++)
405  s->exp_strategy[ch][blk] = EXP_REUSE;
406  }
407 
408  /* for E-AC-3, determine frame exponent strategy */
409  if (CONFIG_EAC3_ENCODER && s->eac3)
411 }
412 
413 
422 static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
423  int cpl)
424 {
425  int nb_groups, i, k;
426 
427  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
428 
429  /* for each group, compute the minimum exponent */
430  switch(exp_strategy) {
431  case EXP_D25:
432  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
433  uint8_t exp_min = exp[k];
434  if (exp[k+1] < exp_min)
435  exp_min = exp[k+1];
436  exp[i-cpl] = exp_min;
437  k += 2;
438  }
439  break;
440  case EXP_D45:
441  for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
442  uint8_t exp_min = exp[k];
443  if (exp[k+1] < exp_min)
444  exp_min = exp[k+1];
445  if (exp[k+2] < exp_min)
446  exp_min = exp[k+2];
447  if (exp[k+3] < exp_min)
448  exp_min = exp[k+3];
449  exp[i-cpl] = exp_min;
450  k += 4;
451  }
452  break;
453  }
454 
455  /* constraint for DC exponent */
456  if (!cpl && exp[0] > 15)
457  exp[0] = 15;
458 
459  /* decrease the delta between each groups to within 2 so that they can be
460  differentially encoded */
461  for (i = 1; i <= nb_groups; i++)
462  exp[i] = FFMIN(exp[i], exp[i-1] + 2);
463  i--;
464  while (--i >= 0)
465  exp[i] = FFMIN(exp[i], exp[i+1] + 2);
466 
467  if (cpl)
468  exp[-1] = exp[0] & ~1;
469 
470  /* now we have the exponent values the decoder will see */
471  switch (exp_strategy) {
472  case EXP_D25:
473  for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
474  uint8_t exp1 = exp[i-cpl];
475  exp[k--] = exp1;
476  exp[k--] = exp1;
477  }
478  break;
479  case EXP_D45:
480  for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
481  exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
482  k -= 4;
483  }
484  break;
485  }
486 }
487 
488 
489 /*
490  * Encode exponents from original extracted form to what the decoder will see.
491  * This copies and groups exponents based on exponent strategy and reduces
492  * deltas between adjacent exponent groups so that they can be differentially
493  * encoded.
494  */
496 {
497  int blk, blk1, ch, cpl;
498  uint8_t *exp, *exp_strategy;
499  int nb_coefs, num_reuse_blocks;
500 
501  for (ch = !s->cpl_on; ch <= s->channels; ch++) {
502  exp = s->blocks[0].exp[ch] + s->start_freq[ch];
503  exp_strategy = s->exp_strategy[ch];
504 
505  cpl = (ch == CPL_CH);
506  blk = 0;
507  while (blk < s->num_blocks) {
508  AC3Block *block = &s->blocks[blk];
509  if (cpl && !block->cpl_in_use) {
510  exp += AC3_MAX_COEFS;
511  blk++;
512  continue;
513  }
514  nb_coefs = block->end_freq[ch] - s->start_freq[ch];
515  blk1 = blk + 1;
516 
517  /* count the number of EXP_REUSE blocks after the current block
518  and set exponent reference block numbers */
519  s->exp_ref_block[ch][blk] = blk;
520  while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
521  s->exp_ref_block[ch][blk1] = blk;
522  blk1++;
523  }
524  num_reuse_blocks = blk1 - blk - 1;
525 
526  /* for the EXP_REUSE case we select the min of the exponents */
527  s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
528  AC3_MAX_COEFS);
529 
530  encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
531 
532  exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
533  blk = blk1;
534  }
535  }
536 
537  /* reference block numbers have been changed, so reset ref_bap_set */
538  s->ref_bap_set = 0;
539 }
540 
541 
542 /*
543  * Count exponent bits based on bandwidth, coupling, and exponent strategies.
544  */
546 {
547  int blk, ch;
548  int nb_groups, bit_count;
549 
550  bit_count = 0;
551  for (blk = 0; blk < s->num_blocks; blk++) {
552  AC3Block *block = &s->blocks[blk];
553  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
554  int exp_strategy = s->exp_strategy[ch][blk];
555  int cpl = (ch == CPL_CH);
556  int nb_coefs = block->end_freq[ch] - s->start_freq[ch];
557 
558  if (exp_strategy == EXP_REUSE)
559  continue;
560 
561  nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
562  bit_count += 4 + (nb_groups * 7);
563  }
564  }
565 
566  return bit_count;
567 }
568 
569 
578 {
579  int blk, ch, i, cpl;
580  int group_size, nb_groups;
581  uint8_t *p;
582  int delta0, delta1, delta2;
583  int exp0, exp1;
584 
585  for (blk = 0; blk < s->num_blocks; blk++) {
586  AC3Block *block = &s->blocks[blk];
587  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
588  int exp_strategy = s->exp_strategy[ch][blk];
589  if (exp_strategy == EXP_REUSE)
590  continue;
591  cpl = (ch == CPL_CH);
592  group_size = exp_strategy + (exp_strategy == EXP_D45);
593  nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
594  p = block->exp[ch] + s->start_freq[ch] - cpl;
595 
596  /* DC exponent */
597  exp1 = *p++;
598  block->grouped_exp[ch][0] = exp1;
599 
600  /* remaining exponents are delta encoded */
601  for (i = 1; i <= nb_groups; i++) {
602  /* merge three delta in one code */
603  exp0 = exp1;
604  exp1 = p[0];
605  p += group_size;
606  delta0 = exp1 - exp0 + 2;
607  av_assert2(delta0 >= 0 && delta0 <= 4);
608 
609  exp0 = exp1;
610  exp1 = p[0];
611  p += group_size;
612  delta1 = exp1 - exp0 + 2;
613  av_assert2(delta1 >= 0 && delta1 <= 4);
614 
615  exp0 = exp1;
616  exp1 = p[0];
617  p += group_size;
618  delta2 = exp1 - exp0 + 2;
619  av_assert2(delta2 >= 0 && delta2 <= 4);
620 
621  block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
622  }
623  }
624  }
625 }
626 
627 
636 {
638 
640 
641  encode_exponents(s);
642 
643  emms_c();
644 }
645 
646 
647 /*
648  * Count frame bits that are based solely on fixed parameters.
649  * This only has to be run once when the encoder is initialized.
650  */
652 {
653  static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
654  int blk;
655  int frame_bits;
656 
657  /* assumptions:
658  * no dynamic range codes
659  * bit allocation parameters do not change between blocks
660  * no delta bit allocation
661  * no skipped data
662  * no auxiliary data
663  * no E-AC-3 metadata
664  */
665 
666  /* header */
667  frame_bits = 16; /* sync info */
668  if (s->eac3) {
669  /* bitstream info header */
670  frame_bits += 35;
671  frame_bits += 1 + 1;
672  if (s->num_blocks != 0x6)
673  frame_bits++;
674  frame_bits++;
675  /* audio frame header */
676  if (s->num_blocks == 6)
677  frame_bits += 2;
678  frame_bits += 10;
679  /* exponent strategy */
680  if (s->use_frame_exp_strategy)
681  frame_bits += 5 * s->fbw_channels;
682  else
683  frame_bits += s->num_blocks * 2 * s->fbw_channels;
684  if (s->lfe_on)
685  frame_bits += s->num_blocks;
686  /* converter exponent strategy */
687  if (s->num_blks_code != 0x3)
688  frame_bits++;
689  else
690  frame_bits += s->fbw_channels * 5;
691  /* snr offsets */
692  frame_bits += 10;
693  /* block start info */
694  if (s->num_blocks != 1)
695  frame_bits++;
696  } else {
697  frame_bits += 49;
698  frame_bits += frame_bits_inc[s->channel_mode];
699  }
700 
701  /* audio blocks */
702  for (blk = 0; blk < s->num_blocks; blk++) {
703  if (!s->eac3) {
704  /* block switch flags */
705  frame_bits += s->fbw_channels;
706 
707  /* dither flags */
708  frame_bits += s->fbw_channels;
709  }
710 
711  /* dynamic range */
712  frame_bits++;
713 
714  /* spectral extension */
715  if (s->eac3)
716  frame_bits++;
717 
718  if (!s->eac3) {
719  /* exponent strategy */
720  frame_bits += 2 * s->fbw_channels;
721  if (s->lfe_on)
722  frame_bits++;
723 
724  /* bit allocation params */
725  frame_bits++;
726  if (!blk)
727  frame_bits += 2 + 2 + 2 + 2 + 3;
728  }
729 
730  /* converter snr offset */
731  if (s->eac3)
732  frame_bits++;
733 
734  if (!s->eac3) {
735  /* delta bit allocation */
736  frame_bits++;
737 
738  /* skipped data */
739  frame_bits++;
740  }
741  }
742 
743  /* auxiliary data */
744  frame_bits++;
745 
746  /* CRC */
747  frame_bits += 1 + 16;
748 
749  s->frame_bits_fixed = frame_bits;
750 }
751 
752 
753 /*
754  * Initialize bit allocation.
755  * Set default parameter codes and calculate parameter values.
756  */
758 {
759  int ch;
760 
761  /* init default parameters */
762  s->slow_decay_code = 2;
763  s->fast_decay_code = 1;
764  s->slow_gain_code = 1;
765  s->db_per_bit_code = s->eac3 ? 2 : 3;
766  s->floor_code = 7;
767  for (ch = 0; ch <= s->channels; ch++)
768  s->fast_gain_code[ch] = 4;
769 
770  /* initial snr offset */
771  s->coarse_snr_offset = 40;
772 
773  /* compute real values */
774  /* currently none of these values change during encoding, so we can just
775  set them once at initialization */
781  s->bit_alloc.cpl_fast_leak = 0;
782  s->bit_alloc.cpl_slow_leak = 0;
783 
785 }
786 
787 
788 /*
789  * Count the bits used to encode the frame, minus exponents and mantissas.
790  * Bits based on fixed parameters have already been counted, so now we just
791  * have to add the bits based on parameters that change during encoding.
792  */
794 {
795  AC3EncOptions *opt = &s->options;
796  int blk, ch;
797  int frame_bits = 0;
798 
799  /* header */
800  if (s->eac3) {
801  if (opt->eac3_mixing_metadata) {
803  frame_bits += 2;
804  if (s->has_center)
805  frame_bits += 6;
806  if (s->has_surround)
807  frame_bits += 6;
808  frame_bits += s->lfe_on;
809  frame_bits += 1 + 1 + 2;
811  frame_bits++;
812  frame_bits++;
813  }
814  if (opt->eac3_info_metadata) {
815  frame_bits += 3 + 1 + 1;
817  frame_bits += 2 + 2;
818  if (s->channel_mode >= AC3_CHMODE_2F2R)
819  frame_bits += 2;
820  frame_bits++;
821  if (opt->audio_production_info)
822  frame_bits += 5 + 2 + 1;
823  frame_bits++;
824  }
825  /* coupling */
826  if (s->channel_mode > AC3_CHMODE_MONO) {
827  frame_bits++;
828  for (blk = 1; blk < s->num_blocks; blk++) {
829  AC3Block *block = &s->blocks[blk];
830  frame_bits++;
831  if (block->new_cpl_strategy)
832  frame_bits++;
833  }
834  }
835  /* coupling exponent strategy */
836  if (s->cpl_on) {
837  if (s->use_frame_exp_strategy) {
838  frame_bits += 5 * s->cpl_on;
839  } else {
840  for (blk = 0; blk < s->num_blocks; blk++)
841  frame_bits += 2 * s->blocks[blk].cpl_in_use;
842  }
843  }
844  } else {
845  if (opt->audio_production_info)
846  frame_bits += 7;
847  if (s->bitstream_id == 6) {
848  if (opt->extended_bsi_1)
849  frame_bits += 14;
850  if (opt->extended_bsi_2)
851  frame_bits += 14;
852  }
853  }
854 
855  /* audio blocks */
856  for (blk = 0; blk < s->num_blocks; blk++) {
857  AC3Block *block = &s->blocks[blk];
858 
859  /* coupling strategy */
860  if (!s->eac3)
861  frame_bits++;
862  if (block->new_cpl_strategy) {
863  if (!s->eac3)
864  frame_bits++;
865  if (block->cpl_in_use) {
866  if (s->eac3)
867  frame_bits++;
868  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
869  frame_bits += s->fbw_channels;
871  frame_bits++;
872  frame_bits += 4 + 4;
873  if (s->eac3)
874  frame_bits++;
875  else
876  frame_bits += s->num_cpl_subbands - 1;
877  }
878  }
879 
880  /* coupling coordinates */
881  if (block->cpl_in_use) {
882  for (ch = 1; ch <= s->fbw_channels; ch++) {
883  if (block->channel_in_cpl[ch]) {
884  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
885  frame_bits++;
886  if (block->new_cpl_coords[ch]) {
887  frame_bits += 2;
888  frame_bits += (4 + 4) * s->num_cpl_bands;
889  }
890  }
891  }
892  }
893 
894  /* stereo rematrixing */
895  if (s->channel_mode == AC3_CHMODE_STEREO) {
896  if (!s->eac3 || blk > 0)
897  frame_bits++;
898  if (s->blocks[blk].new_rematrixing_strategy)
899  frame_bits += block->num_rematrixing_bands;
900  }
901 
902  /* bandwidth codes & gain range */
903  for (ch = 1; ch <= s->fbw_channels; ch++) {
904  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
905  if (!block->channel_in_cpl[ch])
906  frame_bits += 6;
907  frame_bits += 2;
908  }
909  }
910 
911  /* coupling exponent strategy */
912  if (!s->eac3 && block->cpl_in_use)
913  frame_bits += 2;
914 
915  /* snr offsets and fast gain codes */
916  if (!s->eac3) {
917  frame_bits++;
918  if (block->new_snr_offsets)
919  frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
920  }
921 
922  /* coupling leak info */
923  if (block->cpl_in_use) {
924  if (!s->eac3 || block->new_cpl_leak != 2)
925  frame_bits++;
926  if (block->new_cpl_leak)
927  frame_bits += 3 + 3;
928  }
929  }
930 
931  s->frame_bits = s->frame_bits_fixed + frame_bits;
932 }
933 
934 
935 /*
936  * Calculate masking curve based on the final exponents.
937  * Also calculate the power spectral densities to use in future calculations.
938  */
940 {
941  int blk, ch;
942 
943  for (blk = 0; blk < s->num_blocks; blk++) {
944  AC3Block *block = &s->blocks[blk];
945  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
946  /* We only need psd and mask for calculating bap.
947  Since we currently do not calculate bap when exponent
948  strategy is EXP_REUSE we do not need to calculate psd or mask. */
949  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
950  ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
951  block->end_freq[ch], block->psd[ch],
952  block->band_psd[ch]);
954  s->start_freq[ch], block->end_freq[ch],
956  ch == s->lfe_channel,
957  DBA_NONE, 0, NULL, NULL, NULL,
958  block->mask[ch]);
959  }
960  }
961  }
962 }
963 
964 
965 /*
966  * Ensure that bap for each block and channel point to the current bap_buffer.
967  * They may have been switched during the bit allocation search.
968  */
970 {
971  int blk, ch;
972  uint8_t *ref_bap;
973 
974  if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
975  return;
976 
977  ref_bap = s->bap_buffer;
978  for (ch = 0; ch <= s->channels; ch++) {
979  for (blk = 0; blk < s->num_blocks; blk++)
980  s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
981  ref_bap += AC3_MAX_COEFS * s->num_blocks;
982  }
983  s->ref_bap_set = 1;
984 }
985 
986 
994 static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
995 {
996  int blk;
997 
998  for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
999  memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
1000  mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
1001  mant_cnt[blk][4] = 1;
1002  }
1003 }
1004 
1005 
1017  uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
1018  int start, int end)
1019 {
1020  int blk;
1021 
1022  for (blk = 0; blk < s->num_blocks; blk++) {
1023  AC3Block *block = &s->blocks[blk];
1024  if (ch == CPL_CH && !block->cpl_in_use)
1025  continue;
1026  s->ac3dsp.update_bap_counts(mant_cnt[blk],
1027  s->ref_bap[ch][blk] + start,
1028  FFMIN(end, block->end_freq[ch]) - start);
1029  }
1030 }
1031 
1032 
1033 /*
1034  * Count the number of mantissa bits in the frame based on the bap values.
1035  */
1037 {
1038  int ch, max_end_freq;
1039  LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
1040 
1041  count_mantissa_bits_init(mant_cnt);
1042 
1043  max_end_freq = s->bandwidth_code * 3 + 73;
1044  for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
1045  count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
1046  max_end_freq);
1047 
1048  return s->ac3dsp.compute_mantissa_size(mant_cnt);
1049 }
1050 
1051 
1062 static int bit_alloc(AC3EncodeContext *s, int snr_offset)
1063 {
1064  int blk, ch;
1065 
1066  snr_offset = (snr_offset - 240) << 2;
1067 
1068  reset_block_bap(s);
1069  for (blk = 0; blk < s->num_blocks; blk++) {
1070  AC3Block *block = &s->blocks[blk];
1071 
1072  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1073  /* Currently the only bit allocation parameters which vary across
1074  blocks within a frame are the exponent values. We can take
1075  advantage of that by reusing the bit allocation pointers
1076  whenever we reuse exponents. */
1077  if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1078  s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
1079  s->start_freq[ch], block->end_freq[ch],
1080  snr_offset, s->bit_alloc.floor,
1081  ff_ac3_bap_tab, s->ref_bap[ch][blk]);
1082  }
1083  }
1084  }
1085  return count_mantissa_bits(s);
1086 }
1087 
1088 
1089 /*
1090  * Constant bitrate bit allocation search.
1091  * Find the largest SNR offset that will allow data to fit in the frame.
1092  */
1094 {
1095  int ch;
1096  int bits_left;
1097  int snr_offset, snr_incr;
1098 
1099  bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
1100  if (bits_left < 0)
1101  return AVERROR(EINVAL);
1102 
1103  snr_offset = s->coarse_snr_offset << 4;
1104 
1105  /* if previous frame SNR offset was 1023, check if current frame can also
1106  use SNR offset of 1023. if so, skip the search. */
1107  if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
1108  if (bit_alloc(s, 1023) <= bits_left)
1109  return 0;
1110  }
1111 
1112  while (snr_offset >= 0 &&
1113  bit_alloc(s, snr_offset) > bits_left) {
1114  snr_offset -= 64;
1115  }
1116  if (snr_offset < 0)
1117  return AVERROR(EINVAL);
1118 
1119  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1120  for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
1121  while (snr_offset + snr_incr <= 1023 &&
1122  bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
1123  snr_offset += snr_incr;
1124  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1125  }
1126  }
1127  FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1128  reset_block_bap(s);
1129 
1130  s->coarse_snr_offset = snr_offset >> 4;
1131  for (ch = !s->cpl_on; ch <= s->channels; ch++)
1132  s->fine_snr_offset[ch] = snr_offset & 0xF;
1133 
1134  return 0;
1135 }
1136 
1137 
1138 /*
1139  * Perform bit allocation search.
1140  * Finds the SNR offset value that maximizes quality and fits in the specified
1141  * frame size. Output is the SNR offset and a set of bit allocation pointers
1142  * used to quantize the mantissas.
1143  */
1145 {
1146  count_frame_bits(s);
1147 
1149 
1150  bit_alloc_masking(s);
1151 
1152  return cbr_bit_allocation(s);
1153 }
1154 
1155 
1164 static inline int sym_quant(int c, int e, int levels)
1165 {
1166  int v = (((levels * c) >> (24 - e)) + levels) >> 1;
1167  av_assert2(v >= 0 && v < levels);
1168  return v;
1169 }
1170 
1171 
1180 static inline int asym_quant(int c, int e, int qbits)
1181 {
1182  int m;
1183 
1184  c = (((c << e) >> (24 - qbits)) + 1) >> 1;
1185  m = (1 << (qbits-1));
1186  if (c >= m)
1187  c = m - 1;
1188  av_assert2(c >= -m);
1189  return c;
1190 }
1191 
1192 
1204 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
1205  uint8_t *exp, uint8_t *bap,
1206  int16_t *qmant, int start_freq,
1207  int end_freq)
1208 {
1209  int i;
1210 
1211  for (i = start_freq; i < end_freq; i++) {
1212  int v;
1213  int c = fixed_coef[i];
1214  int e = exp[i];
1215  int b = bap[i];
1216  switch (b) {
1217  case 0:
1218  v = 0;
1219  break;
1220  case 1:
1221  v = sym_quant(c, e, 3);
1222  switch (s->mant1_cnt) {
1223  case 0:
1224  s->qmant1_ptr = &qmant[i];
1225  v = 9 * v;
1226  s->mant1_cnt = 1;
1227  break;
1228  case 1:
1229  *s->qmant1_ptr += 3 * v;
1230  s->mant1_cnt = 2;
1231  v = 128;
1232  break;
1233  default:
1234  *s->qmant1_ptr += v;
1235  s->mant1_cnt = 0;
1236  v = 128;
1237  break;
1238  }
1239  break;
1240  case 2:
1241  v = sym_quant(c, e, 5);
1242  switch (s->mant2_cnt) {
1243  case 0:
1244  s->qmant2_ptr = &qmant[i];
1245  v = 25 * v;
1246  s->mant2_cnt = 1;
1247  break;
1248  case 1:
1249  *s->qmant2_ptr += 5 * v;
1250  s->mant2_cnt = 2;
1251  v = 128;
1252  break;
1253  default:
1254  *s->qmant2_ptr += v;
1255  s->mant2_cnt = 0;
1256  v = 128;
1257  break;
1258  }
1259  break;
1260  case 3:
1261  v = sym_quant(c, e, 7);
1262  break;
1263  case 4:
1264  v = sym_quant(c, e, 11);
1265  switch (s->mant4_cnt) {
1266  case 0:
1267  s->qmant4_ptr = &qmant[i];
1268  v = 11 * v;
1269  s->mant4_cnt = 1;
1270  break;
1271  default:
1272  *s->qmant4_ptr += v;
1273  s->mant4_cnt = 0;
1274  v = 128;
1275  break;
1276  }
1277  break;
1278  case 5:
1279  v = sym_quant(c, e, 15);
1280  break;
1281  case 14:
1282  v = asym_quant(c, e, 14);
1283  break;
1284  case 15:
1285  v = asym_quant(c, e, 16);
1286  break;
1287  default:
1288  v = asym_quant(c, e, b - 1);
1289  break;
1290  }
1291  qmant[i] = v;
1292  }
1293 }
1294 
1295 
1302 {
1303  int blk, ch, ch0=0, got_cpl;
1304 
1305  for (blk = 0; blk < s->num_blocks; blk++) {
1306  AC3Block *block = &s->blocks[blk];
1307  AC3Mant m = { 0 };
1308 
1309  got_cpl = !block->cpl_in_use;
1310  for (ch = 1; ch <= s->channels; ch++) {
1311  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1312  ch0 = ch - 1;
1313  ch = CPL_CH;
1314  got_cpl = 1;
1315  }
1316  quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
1317  s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
1318  s->ref_bap[ch][blk], block->qmant[ch],
1319  s->start_freq[ch], block->end_freq[ch]);
1320  if (ch == CPL_CH)
1321  ch = ch0;
1322  }
1323  }
1324 }
1325 
1326 
1327 /*
1328  * Write the AC-3 frame header to the output bitstream.
1329  */
1331 {
1332  AC3EncOptions *opt = &s->options;
1333 
1334  put_bits(&s->pb, 16, 0x0b77); /* frame header */
1335  put_bits(&s->pb, 16, 0); /* crc1: will be filled later */
1336  put_bits(&s->pb, 2, s->bit_alloc.sr_code);
1337  put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
1338  put_bits(&s->pb, 5, s->bitstream_id);
1339  put_bits(&s->pb, 3, s->bitstream_mode);
1340  put_bits(&s->pb, 3, s->channel_mode);
1341  if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
1342  put_bits(&s->pb, 2, s->center_mix_level);
1343  if (s->channel_mode & 0x04)
1344  put_bits(&s->pb, 2, s->surround_mix_level);
1345  if (s->channel_mode == AC3_CHMODE_STEREO)
1346  put_bits(&s->pb, 2, opt->dolby_surround_mode);
1347  put_bits(&s->pb, 1, s->lfe_on); /* LFE */
1348  put_bits(&s->pb, 5, -opt->dialogue_level);
1349  put_bits(&s->pb, 1, 0); /* no compression control word */
1350  put_bits(&s->pb, 1, 0); /* no lang code */
1351  put_bits(&s->pb, 1, opt->audio_production_info);
1352  if (opt->audio_production_info) {
1353  put_bits(&s->pb, 5, opt->mixing_level - 80);
1354  put_bits(&s->pb, 2, opt->room_type);
1355  }
1356  put_bits(&s->pb, 1, opt->copyright);
1357  put_bits(&s->pb, 1, opt->original);
1358  if (s->bitstream_id == 6) {
1359  /* alternate bit stream syntax */
1360  put_bits(&s->pb, 1, opt->extended_bsi_1);
1361  if (opt->extended_bsi_1) {
1362  put_bits(&s->pb, 2, opt->preferred_stereo_downmix);
1363  put_bits(&s->pb, 3, s->ltrt_center_mix_level);
1364  put_bits(&s->pb, 3, s->ltrt_surround_mix_level);
1365  put_bits(&s->pb, 3, s->loro_center_mix_level);
1366  put_bits(&s->pb, 3, s->loro_surround_mix_level);
1367  }
1368  put_bits(&s->pb, 1, opt->extended_bsi_2);
1369  if (opt->extended_bsi_2) {
1370  put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);
1371  put_bits(&s->pb, 2, opt->dolby_headphone_mode);
1372  put_bits(&s->pb, 1, opt->ad_converter_type);
1373  put_bits(&s->pb, 9, 0); /* xbsi2 and encinfo : reserved */
1374  }
1375  } else {
1376  put_bits(&s->pb, 1, 0); /* no time code 1 */
1377  put_bits(&s->pb, 1, 0); /* no time code 2 */
1378  }
1379  put_bits(&s->pb, 1, 0); /* no additional bit stream info */
1380 }
1381 
1382 
1383 /*
1384  * Write one audio block to the output bitstream.
1385  */
1387 {
1388  int ch, i, baie, bnd, got_cpl, ch0;
1389  AC3Block *block = &s->blocks[blk];
1390 
1391  /* block switching */
1392  if (!s->eac3) {
1393  for (ch = 0; ch < s->fbw_channels; ch++)
1394  put_bits(&s->pb, 1, 0);
1395  }
1396 
1397  /* dither flags */
1398  if (!s->eac3) {
1399  for (ch = 0; ch < s->fbw_channels; ch++)
1400  put_bits(&s->pb, 1, 1);
1401  }
1402 
1403  /* dynamic range codes */
1404  put_bits(&s->pb, 1, 0);
1405 
1406  /* spectral extension */
1407  if (s->eac3)
1408  put_bits(&s->pb, 1, 0);
1409 
1410  /* channel coupling */
1411  if (!s->eac3)
1412  put_bits(&s->pb, 1, block->new_cpl_strategy);
1413  if (block->new_cpl_strategy) {
1414  if (!s->eac3)
1415  put_bits(&s->pb, 1, block->cpl_in_use);
1416  if (block->cpl_in_use) {
1417  int start_sub, end_sub;
1418  if (s->eac3)
1419  put_bits(&s->pb, 1, 0); /* enhanced coupling */
1420  if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
1421  for (ch = 1; ch <= s->fbw_channels; ch++)
1422  put_bits(&s->pb, 1, block->channel_in_cpl[ch]);
1423  }
1424  if (s->channel_mode == AC3_CHMODE_STEREO)
1425  put_bits(&s->pb, 1, 0); /* phase flags in use */
1426  start_sub = (s->start_freq[CPL_CH] - 37) / 12;
1427  end_sub = (s->cpl_end_freq - 37) / 12;
1428  put_bits(&s->pb, 4, start_sub);
1429  put_bits(&s->pb, 4, end_sub - 3);
1430  /* coupling band structure */
1431  if (s->eac3) {
1432  put_bits(&s->pb, 1, 0); /* use default */
1433  } else {
1434  for (bnd = start_sub+1; bnd < end_sub; bnd++)
1436  }
1437  }
1438  }
1439 
1440  /* coupling coordinates */
1441  if (block->cpl_in_use) {
1442  for (ch = 1; ch <= s->fbw_channels; ch++) {
1443  if (block->channel_in_cpl[ch]) {
1444  if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1445  put_bits(&s->pb, 1, block->new_cpl_coords[ch]);
1446  if (block->new_cpl_coords[ch]) {
1447  put_bits(&s->pb, 2, block->cpl_master_exp[ch]);
1448  for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
1449  put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);
1450  put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]);
1451  }
1452  }
1453  }
1454  }
1455  }
1456 
1457  /* stereo rematrixing */
1458  if (s->channel_mode == AC3_CHMODE_STEREO) {
1459  if (!s->eac3 || blk > 0)
1460  put_bits(&s->pb, 1, block->new_rematrixing_strategy);
1461  if (block->new_rematrixing_strategy) {
1462  /* rematrixing flags */
1463  for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
1464  put_bits(&s->pb, 1, block->rematrixing_flags[bnd]);
1465  }
1466  }
1467 
1468  /* exponent strategy */
1469  if (!s->eac3) {
1470  for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
1471  put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
1472  if (s->lfe_on)
1473  put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
1474  }
1475 
1476  /* bandwidth */
1477  for (ch = 1; ch <= s->fbw_channels; ch++) {
1478  if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
1479  put_bits(&s->pb, 6, s->bandwidth_code);
1480  }
1481 
1482  /* exponents */
1483  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1484  int nb_groups;
1485  int cpl = (ch == CPL_CH);
1486 
1487  if (s->exp_strategy[ch][blk] == EXP_REUSE)
1488  continue;
1489 
1490  /* DC exponent */
1491  put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl);
1492 
1493  /* exponent groups */
1494  nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
1495  for (i = 1; i <= nb_groups; i++)
1496  put_bits(&s->pb, 7, block->grouped_exp[ch][i]);
1497 
1498  /* gain range info */
1499  if (ch != s->lfe_channel && !cpl)
1500  put_bits(&s->pb, 2, 0);
1501  }
1502 
1503  /* bit allocation info */
1504  if (!s->eac3) {
1505  baie = (blk == 0);
1506  put_bits(&s->pb, 1, baie);
1507  if (baie) {
1508  put_bits(&s->pb, 2, s->slow_decay_code);
1509  put_bits(&s->pb, 2, s->fast_decay_code);
1510  put_bits(&s->pb, 2, s->slow_gain_code);
1511  put_bits(&s->pb, 2, s->db_per_bit_code);
1512  put_bits(&s->pb, 3, s->floor_code);
1513  }
1514  }
1515 
1516  /* snr offset */
1517  if (!s->eac3) {
1518  put_bits(&s->pb, 1, block->new_snr_offsets);
1519  if (block->new_snr_offsets) {
1520  put_bits(&s->pb, 6, s->coarse_snr_offset);
1521  for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1522  put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
1523  put_bits(&s->pb, 3, s->fast_gain_code[ch]);
1524  }
1525  }
1526  } else {
1527  put_bits(&s->pb, 1, 0); /* no converter snr offset */
1528  }
1529 
1530  /* coupling leak */
1531  if (block->cpl_in_use) {
1532  if (!s->eac3 || block->new_cpl_leak != 2)
1533  put_bits(&s->pb, 1, block->new_cpl_leak);
1534  if (block->new_cpl_leak) {
1535  put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak);
1536  put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak);
1537  }
1538  }
1539 
1540  if (!s->eac3) {
1541  put_bits(&s->pb, 1, 0); /* no delta bit allocation */
1542  put_bits(&s->pb, 1, 0); /* no data to skip */
1543  }
1544 
1545  /* mantissas */
1546  got_cpl = !block->cpl_in_use;
1547  for (ch = 1; ch <= s->channels; ch++) {
1548  int b, q;
1549 
1550  if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1551  ch0 = ch - 1;
1552  ch = CPL_CH;
1553  got_cpl = 1;
1554  }
1555  for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
1556  q = block->qmant[ch][i];
1557  b = s->ref_bap[ch][blk][i];
1558  switch (b) {
1559  case 0: break;
1560  case 1: if (q != 128) put_bits (&s->pb, 5, q); break;
1561  case 2: if (q != 128) put_bits (&s->pb, 7, q); break;
1562  case 3: put_sbits(&s->pb, 3, q); break;
1563  case 4: if (q != 128) put_bits (&s->pb, 7, q); break;
1564  case 14: put_sbits(&s->pb, 14, q); break;
1565  case 15: put_sbits(&s->pb, 16, q); break;
1566  default: put_sbits(&s->pb, b-1, q); break;
1567  }
1568  }
1569  if (ch == CPL_CH)
1570  ch = ch0;
1571  }
1572 }
1573 
1574 
1576 #define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
1577 
1578 
1579 static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
1580 {
1581  unsigned int c;
1582 
1583  c = 0;
1584  while (a) {
1585  if (a & 1)
1586  c ^= b;
1587  a = a >> 1;
1588  b = b << 1;
1589  if (b & (1 << 16))
1590  b ^= poly;
1591  }
1592  return c;
1593 }
1594 
1595 
1596 static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
1597 {
1598  unsigned int r;
1599  r = 1;
1600  while (n) {
1601  if (n & 1)
1602  r = mul_poly(r, a, poly);
1603  a = mul_poly(a, a, poly);
1604  n >>= 1;
1605  }
1606  return r;
1607 }
1608 
1609 
1610 /*
1611  * Fill the end of the frame with 0's and compute the two CRCs.
1612  */
1614 {
1615  const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
1616  int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv;
1617  uint8_t *frame;
1618 
1619  frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
1620 
1621  /* pad the remainder of the frame with zeros */
1622  av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18);
1623  flush_put_bits(&s->pb);
1624  frame = s->pb.buf;
1625  pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
1626  av_assert2(pad_bytes >= 0);
1627  if (pad_bytes > 0)
1628  memset(put_bits_ptr(&s->pb), 0, pad_bytes);
1629 
1630  if (s->eac3) {
1631  /* compute crc2 */
1632  crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5);
1633  } else {
1634  /* compute crc1 */
1635  /* this is not so easy because it is at the beginning of the data... */
1636  crc1 = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
1637  crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
1638  crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
1639  AV_WB16(frame + 2, crc1);
1640 
1641  /* compute crc2 */
1642  crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58,
1643  s->frame_size - frame_size_58 - 3);
1644  }
1645  crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1646  /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
1647  if (crc2 == 0x770B) {
1648  frame[s->frame_size - 3] ^= 0x1;
1649  crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1650  }
1651  crc2 = av_bswap16(crc2);
1652  AV_WB16(frame + s->frame_size - 2, crc2);
1653 }
1654 
1655 
1662 void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
1663 {
1664  int blk;
1665 
1667 
1668  s->output_frame_header(s);
1669 
1670  for (blk = 0; blk < s->num_blocks; blk++)
1671  output_audio_block(s, blk);
1672 
1673  output_frame_end(s);
1674 }
1675 
1676 
1678 {
1679 #ifdef DEBUG
1680  AVCodecContext *avctx = s->avctx;
1681  AC3EncOptions *opt = &s->options;
1682  char strbuf[32];
1683 
1684  switch (s->bitstream_id) {
1685  case 6: av_strlcpy(strbuf, "AC-3 (alt syntax)", 32); break;
1686  case 8: av_strlcpy(strbuf, "AC-3 (standard)", 32); break;
1687  case 9: av_strlcpy(strbuf, "AC-3 (dnet half-rate)", 32); break;
1688  case 10: av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break;
1689  case 16: av_strlcpy(strbuf, "E-AC-3 (enhanced)", 32); break;
1690  default: snprintf(strbuf, 32, "ERROR");
1691  }
1692  av_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id);
1693  av_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
1694  av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout);
1695  av_dlog(avctx, "channel_layout: %s\n", strbuf);
1696  av_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
1697  av_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
1698  av_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
1699  if (s->cutoff)
1700  av_dlog(avctx, "cutoff: %d\n", s->cutoff);
1701 
1702  av_dlog(avctx, "per_frame_metadata: %s\n",
1703  opt->allow_per_frame_metadata?"on":"off");
1704  if (s->has_center)
1705  av_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
1706  s->center_mix_level);
1707  else
1708  av_dlog(avctx, "center_mixlev: {not written}\n");
1709  if (s->has_surround)
1710  av_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
1711  s->surround_mix_level);
1712  else
1713  av_dlog(avctx, "surround_mixlev: {not written}\n");
1714  if (opt->audio_production_info) {
1715  av_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
1716  switch (opt->room_type) {
1717  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1718  case AC3ENC_OPT_LARGE_ROOM: av_strlcpy(strbuf, "large", 32); break;
1719  case AC3ENC_OPT_SMALL_ROOM: av_strlcpy(strbuf, "small", 32); break;
1720  default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type);
1721  }
1722  av_dlog(avctx, "room_type: %s\n", strbuf);
1723  } else {
1724  av_dlog(avctx, "mixing_level: {not written}\n");
1725  av_dlog(avctx, "room_type: {not written}\n");
1726  }
1727  av_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
1728  av_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
1729  if (s->channel_mode == AC3_CHMODE_STEREO) {
1730  switch (opt->dolby_surround_mode) {
1731  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1732  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1733  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1734  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode);
1735  }
1736  av_dlog(avctx, "dsur_mode: %s\n", strbuf);
1737  } else {
1738  av_dlog(avctx, "dsur_mode: {not written}\n");
1739  }
1740  av_dlog(avctx, "original: %s\n", opt->original?"on":"off");
1741 
1742  if (s->bitstream_id == 6) {
1743  if (opt->extended_bsi_1) {
1744  switch (opt->preferred_stereo_downmix) {
1745  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1746  case AC3ENC_OPT_DOWNMIX_LTRT: av_strlcpy(strbuf, "ltrt", 32); break;
1747  case AC3ENC_OPT_DOWNMIX_LORO: av_strlcpy(strbuf, "loro", 32); break;
1748  default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix);
1749  }
1750  av_dlog(avctx, "dmix_mode: %s\n", strbuf);
1751  av_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
1753  av_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
1755  av_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
1757  av_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
1759  } else {
1760  av_dlog(avctx, "extended bitstream info 1: {not written}\n");
1761  }
1762  if (opt->extended_bsi_2) {
1763  switch (opt->dolby_surround_ex_mode) {
1764  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1765  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1766  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1767  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode);
1768  }
1769  av_dlog(avctx, "dsurex_mode: %s\n", strbuf);
1770  switch (opt->dolby_headphone_mode) {
1771  case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1772  case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;
1773  case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;
1774  default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode);
1775  }
1776  av_dlog(avctx, "dheadphone_mode: %s\n", strbuf);
1777 
1778  switch (opt->ad_converter_type) {
1779  case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break;
1780  case AC3ENC_OPT_ADCONV_HDCD: av_strlcpy(strbuf, "hdcd", 32); break;
1781  default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type);
1782  }
1783  av_dlog(avctx, "ad_conv_type: %s\n", strbuf);
1784  } else {
1785  av_dlog(avctx, "extended bitstream info 2: {not written}\n");
1786  }
1787  }
1788 #endif
1789 }
1790 
1791 
1792 #define FLT_OPTION_THRESHOLD 0.01
1793 
1794 static int validate_float_option(float v, const float *v_list, int v_list_size)
1795 {
1796  int i;
1797 
1798  for (i = 0; i < v_list_size; i++) {
1799  if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
1800  v > (v_list[i] - FLT_OPTION_THRESHOLD))
1801  break;
1802  }
1803  if (i == v_list_size)
1804  return -1;
1805 
1806  return i;
1807 }
1808 
1809 
1810 static void validate_mix_level(void *log_ctx, const char *opt_name,
1811  float *opt_param, const float *list,
1812  int list_size, int default_value, int min_value,
1813  int *ctx_param)
1814 {
1815  int mixlev = validate_float_option(*opt_param, list, list_size);
1816  if (mixlev < min_value) {
1817  mixlev = default_value;
1818  if (*opt_param >= 0.0) {
1819  av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
1820  "default value: %0.3f\n", opt_name, list[mixlev]);
1821  }
1822  }
1823  *opt_param = list[mixlev];
1824  *ctx_param = mixlev;
1825 }
1826 
1827 
1835 {
1836  AVCodecContext *avctx = s->avctx;
1837  AC3EncOptions *opt = &s->options;
1838 
1839  opt->audio_production_info = 0;
1840  opt->extended_bsi_1 = 0;
1841  opt->extended_bsi_2 = 0;
1842  opt->eac3_mixing_metadata = 0;
1843  opt->eac3_info_metadata = 0;
1844 
1845  /* determine mixing metadata / xbsi1 use */
1847  opt->extended_bsi_1 = 1;
1848  opt->eac3_mixing_metadata = 1;
1849  }
1850  if (s->has_center &&
1851  (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
1852  opt->extended_bsi_1 = 1;
1853  opt->eac3_mixing_metadata = 1;
1854  }
1855  if (s->has_surround &&
1856  (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
1857  opt->extended_bsi_1 = 1;
1858  opt->eac3_mixing_metadata = 1;
1859  }
1860 
1861  if (s->eac3) {
1862  /* determine info metadata use */
1864  opt->eac3_info_metadata = 1;
1865  if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
1866  opt->eac3_info_metadata = 1;
1867  if (s->channel_mode == AC3_CHMODE_STEREO &&
1869  opt->eac3_info_metadata = 1;
1871  opt->eac3_info_metadata = 1;
1872  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
1874  opt->audio_production_info = 1;
1875  opt->eac3_info_metadata = 1;
1876  }
1877  } else {
1878  /* determine audio production info use */
1879  if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
1880  opt->audio_production_info = 1;
1881 
1882  /* determine xbsi2 use */
1884  opt->extended_bsi_2 = 1;
1886  opt->extended_bsi_2 = 1;
1887  if (opt->ad_converter_type != AC3ENC_OPT_NONE)
1888  opt->extended_bsi_2 = 1;
1889  }
1890 
1891  /* validate AC-3 mixing levels */
1892  if (!s->eac3) {
1893  if (s->has_center) {
1894  validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
1896  &s->center_mix_level);
1897  }
1898  if (s->has_surround) {
1899  validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
1901  &s->surround_mix_level);
1902  }
1903  }
1904 
1905  /* validate extended bsi 1 / mixing metadata */
1906  if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
1907  /* default preferred stereo downmix */
1910  if (!s->eac3 || s->has_center) {
1911  /* validate Lt/Rt center mix level */
1912  validate_mix_level(avctx, "ltrt_center_mix_level",
1914  EXTMIXLEV_NUM_OPTIONS, 5, 0,
1915  &s->ltrt_center_mix_level);
1916  /* validate Lo/Ro center mix level */
1917  validate_mix_level(avctx, "loro_center_mix_level",
1919  EXTMIXLEV_NUM_OPTIONS, 5, 0,
1920  &s->loro_center_mix_level);
1921  }
1922  if (!s->eac3 || s->has_surround) {
1923  /* validate Lt/Rt surround mix level */
1924  validate_mix_level(avctx, "ltrt_surround_mix_level",
1926  EXTMIXLEV_NUM_OPTIONS, 6, 3,
1928  /* validate Lo/Ro surround mix level */
1929  validate_mix_level(avctx, "loro_surround_mix_level",
1931  EXTMIXLEV_NUM_OPTIONS, 6, 3,
1933  }
1934  }
1935 
1936  /* validate audio service type / channels combination */
1938  avctx->channels == 1) ||
1942  && avctx->channels > 1)) {
1943  av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
1944  "specified number of channels\n");
1945  return AVERROR(EINVAL);
1946  }
1947 
1948  /* validate extended bsi 2 / info metadata */
1949  if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
1950  /* default dolby headphone mode */
1953  /* default dolby surround ex mode */
1956  /* default A/D converter type */
1957  if (opt->ad_converter_type == AC3ENC_OPT_NONE)
1959  }
1960 
1961  /* copyright & original defaults */
1962  if (!s->eac3 || opt->eac3_info_metadata) {
1963  /* default copyright */
1964  if (opt->copyright == AC3ENC_OPT_NONE)
1965  opt->copyright = AC3ENC_OPT_OFF;
1966  /* default original */
1967  if (opt->original == AC3ENC_OPT_NONE)
1968  opt->original = AC3ENC_OPT_ON;
1969  }
1970 
1971  /* dolby surround mode default */
1972  if (!s->eac3 || opt->eac3_info_metadata) {
1975  }
1976 
1977  /* validate audio production info */
1978  if (opt->audio_production_info) {
1979  if (opt->mixing_level == AC3ENC_OPT_NONE) {
1980  av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
1981  "room_type is set\n");
1982  return AVERROR(EINVAL);
1983  }
1984  if (opt->mixing_level < 80) {
1985  av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
1986  "80dB and 111dB\n");
1987  return AVERROR(EINVAL);
1988  }
1989  /* default room type */
1990  if (opt->room_type == AC3ENC_OPT_NONE)
1992  }
1993 
1994  /* set bitstream id for alternate bitstream syntax */
1995  if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {
1996  if (s->bitstream_id > 8 && s->bitstream_id < 11) {
1997  static int warn_once = 1;
1998  if (warn_once) {
1999  av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "
2000  "not compatible with reduced samplerates. writing of "
2001  "extended bitstream information will be disabled.\n");
2002  warn_once = 0;
2003  }
2004  } else {
2005  s->bitstream_id = 6;
2006  }
2007  }
2008 
2009  return 0;
2010 }
2011 
2012 
2019 {
2020  int blk, ch;
2021  AC3EncodeContext *s = avctx->priv_data;
2022 
2024  for (ch = 0; ch < s->channels; ch++)
2025  av_freep(&s->planar_samples[ch]);
2026  av_freep(&s->planar_samples);
2027  av_freep(&s->bap_buffer);
2028  av_freep(&s->bap1_buffer);
2031  av_freep(&s->exp_buffer);
2033  av_freep(&s->psd_buffer);
2035  av_freep(&s->mask_buffer);
2036  av_freep(&s->qmant_buffer);
2039  for (blk = 0; blk < s->num_blocks; blk++) {
2040  AC3Block *block = &s->blocks[blk];
2041  av_freep(&block->mdct_coef);
2042  av_freep(&block->fixed_coef);
2043  av_freep(&block->exp);
2044  av_freep(&block->grouped_exp);
2045  av_freep(&block->psd);
2046  av_freep(&block->band_psd);
2047  av_freep(&block->mask);
2048  av_freep(&block->qmant);
2049  av_freep(&block->cpl_coord_exp);
2050  av_freep(&block->cpl_coord_mant);
2051  }
2052 
2053  s->mdct_end(s);
2054 
2055 #if FF_API_OLD_ENCODE_AUDIO
2056  av_freep(&avctx->coded_frame);
2057 #endif
2058  return 0;
2059 }
2060 
2061 
2062 /*
2063  * Set channel information during initialization.
2064  */
2065 static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
2066  uint64_t *channel_layout)
2067 {
2068  int ch_layout;
2069 
2070  if (channels < 1 || channels > AC3_MAX_CHANNELS)
2071  return AVERROR(EINVAL);
2072  if (*channel_layout > 0x7FF)
2073  return AVERROR(EINVAL);
2074  ch_layout = *channel_layout;
2075  if (!ch_layout)
2076  ch_layout = av_get_default_channel_layout(channels);
2077 
2078  s->lfe_on = !!(ch_layout & AV_CH_LOW_FREQUENCY);
2079  s->channels = channels;
2080  s->fbw_channels = channels - s->lfe_on;
2081  s->lfe_channel = s->lfe_on ? s->fbw_channels + 1 : -1;
2082  if (s->lfe_on)
2083  ch_layout -= AV_CH_LOW_FREQUENCY;
2084 
2085  switch (ch_layout) {
2087  case AV_CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;
2088  case AV_CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;
2089  case AV_CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;
2090  case AV_CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;
2091  case AV_CH_LAYOUT_QUAD:
2092  case AV_CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;
2093  case AV_CH_LAYOUT_5POINT0:
2094  case AV_CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;
2095  default:
2096  return AVERROR(EINVAL);
2097  }
2098  s->has_center = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
2099  s->has_surround = s->channel_mode & 0x04;
2100 
2102  *channel_layout = ch_layout;
2103  if (s->lfe_on)
2104  *channel_layout |= AV_CH_LOW_FREQUENCY;
2105 
2106  return 0;
2107 }
2108 
2109 
2111 {
2112  AVCodecContext *avctx = s->avctx;
2113  int i, ret, max_sr;
2114 
2115  /* validate channel layout */
2116  if (!avctx->channel_layout) {
2117  av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "
2118  "encoder will guess the layout, but it "
2119  "might be incorrect.\n");
2120  }
2121  ret = set_channel_info(s, avctx->channels, &avctx->channel_layout);
2122  if (ret) {
2123  av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");
2124  return ret;
2125  }
2126 
2127  /* validate sample rate */
2128  /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a
2129  decoder that supports half sample rate so we can validate that
2130  the generated files are correct. */
2131  max_sr = s->eac3 ? 2 : 8;
2132  for (i = 0; i <= max_sr; i++) {
2133  if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)
2134  break;
2135  }
2136  if (i > max_sr) {
2137  av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
2138  return AVERROR(EINVAL);
2139  }
2140  s->sample_rate = avctx->sample_rate;
2141  s->bit_alloc.sr_shift = i / 3;
2142  s->bit_alloc.sr_code = i % 3;
2143  s->bitstream_id = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;
2144 
2145  /* select a default bit rate if not set by the user */
2146  if (!avctx->bit_rate) {
2147  switch (s->fbw_channels) {
2148  case 1: avctx->bit_rate = 96000; break;
2149  case 2: avctx->bit_rate = 192000; break;
2150  case 3: avctx->bit_rate = 320000; break;
2151  case 4: avctx->bit_rate = 384000; break;
2152  case 5: avctx->bit_rate = 448000; break;
2153  }
2154  }
2155 
2156  /* validate bit rate */
2157  if (s->eac3) {
2158  int max_br, min_br, wpf, min_br_dist, min_br_code;
2159  int num_blks_code, num_blocks, frame_samples;
2160 
2161  /* calculate min/max bitrate */
2162  /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
2163  found use either 6 blocks or 1 block, even though 2 or 3 blocks
2164  would work as far as the bit rate is concerned. */
2165  for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
2166  num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
2167  frame_samples = AC3_BLOCK_SIZE * num_blocks;
2168  max_br = 2048 * s->sample_rate / frame_samples * 16;
2169  min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
2170  if (avctx->bit_rate <= max_br)
2171  break;
2172  }
2173  if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
2174  av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
2175  "for this sample rate\n", min_br, max_br);
2176  return AVERROR(EINVAL);
2177  }
2178  s->num_blks_code = num_blks_code;
2179  s->num_blocks = num_blocks;
2180 
2181  /* calculate words-per-frame for the selected bitrate */
2182  wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
2183  av_assert1(wpf > 0 && wpf <= 2048);
2184 
2185  /* find the closest AC-3 bitrate code to the selected bitrate.
2186  this is needed for lookup tables for bandwidth and coupling
2187  parameter selection */
2188  min_br_code = -1;
2189  min_br_dist = INT_MAX;
2190  for (i = 0; i < 19; i++) {
2191  int br_dist = abs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
2192  if (br_dist < min_br_dist) {
2193  min_br_dist = br_dist;
2194  min_br_code = i;
2195  }
2196  }
2197 
2198  /* make sure the minimum frame size is below the average frame size */
2199  s->frame_size_code = min_br_code << 1;
2200  while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
2201  wpf--;
2202  s->frame_size_min = 2 * wpf;
2203  } else {
2204  int best_br = 0, best_code = 0, best_diff = INT_MAX;
2205  for (i = 0; i < 19; i++) {
2206  int br = (ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift) * 1000;
2207  int diff = abs(br - avctx->bit_rate);
2208  if (diff < best_diff) {
2209  best_br = br;
2210  best_code = i;
2211  best_diff = diff;
2212  }
2213  if (!best_diff)
2214  break;
2215  }
2216  avctx->bit_rate = best_br;
2217  s->frame_size_code = best_code << 1;
2219  s->num_blks_code = 0x3;
2220  s->num_blocks = 6;
2221  }
2222  s->bit_rate = avctx->bit_rate;
2223  s->frame_size = s->frame_size_min;
2224 
2225  /* validate cutoff */
2226  if (avctx->cutoff < 0) {
2227  av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
2228  return AVERROR(EINVAL);
2229  }
2230  s->cutoff = avctx->cutoff;
2231  if (s->cutoff > (s->sample_rate >> 1))
2232  s->cutoff = s->sample_rate >> 1;
2233 
2234  ret = ff_ac3_validate_metadata(s);
2235  if (ret)
2236  return ret;
2237 
2240 
2243 
2244  return 0;
2245 }
2246 
2247 
2248 /*
2249  * Set bandwidth for all channels.
2250  * The user can optionally supply a cutoff frequency. Otherwise an appropriate
2251  * default value will be used.
2252  */
2254 {
2255  int blk, ch, cpl_start;
2256 
2257  if (s->cutoff) {
2258  /* calculate bandwidth based on user-specified cutoff frequency */
2259  int fbw_coeffs;
2260  fbw_coeffs = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
2261  s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
2262  } else {
2263  /* use default bandwidth setting */
2264  s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
2265  }
2266 
2267  /* set number of coefficients for each channel */
2268  for (ch = 1; ch <= s->fbw_channels; ch++) {
2269  s->start_freq[ch] = 0;
2270  for (blk = 0; blk < s->num_blocks; blk++)
2271  s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
2272  }
2273  /* LFE channel always has 7 coefs */
2274  if (s->lfe_on) {
2275  s->start_freq[s->lfe_channel] = 0;
2276  for (blk = 0; blk < s->num_blocks; blk++)
2277  s->blocks[blk].end_freq[ch] = 7;
2278  }
2279 
2280  /* initialize coupling strategy */
2281  if (s->cpl_enabled) {
2282  if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
2283  cpl_start = s->options.cpl_start;
2284  } else {
2285  cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
2286  if (cpl_start < 0) {
2288  s->cpl_enabled = 0;
2289  else
2290  cpl_start = 15;
2291  }
2292  }
2293  }
2294  if (s->cpl_enabled) {
2295  int i, cpl_start_band, cpl_end_band;
2296  uint8_t *cpl_band_sizes = s->cpl_band_sizes;
2297 
2298  cpl_end_band = s->bandwidth_code / 4 + 3;
2299  cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
2300 
2301  s->num_cpl_subbands = cpl_end_band - cpl_start_band;
2302 
2303  s->num_cpl_bands = 1;
2304  *cpl_band_sizes = 12;
2305  for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
2307  *cpl_band_sizes += 12;
2308  } else {
2309  s->num_cpl_bands++;
2310  cpl_band_sizes++;
2311  *cpl_band_sizes = 12;
2312  }
2313  }
2314 
2315  s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
2316  s->cpl_end_freq = cpl_end_band * 12 + 37;
2317  for (blk = 0; blk < s->num_blocks; blk++)
2318  s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
2319  }
2320 }
2321 
2322 
2324 {
2325  AVCodecContext *avctx = s->avctx;
2326  int blk, ch;
2327  int channels = s->channels + 1; /* includes coupling channel */
2328  int channel_blocks = channels * s->num_blocks;
2329  int total_coefs = AC3_MAX_COEFS * channel_blocks;
2330 
2331  if (s->allocate_sample_buffers(s))
2332  goto alloc_fail;
2333 
2334  FF_ALLOC_OR_GOTO(avctx, s->bap_buffer, total_coefs *
2335  sizeof(*s->bap_buffer), alloc_fail);
2336  FF_ALLOC_OR_GOTO(avctx, s->bap1_buffer, total_coefs *
2337  sizeof(*s->bap1_buffer), alloc_fail);
2338  FF_ALLOCZ_OR_GOTO(avctx, s->mdct_coef_buffer, total_coefs *
2339  sizeof(*s->mdct_coef_buffer), alloc_fail);
2340  FF_ALLOC_OR_GOTO(avctx, s->exp_buffer, total_coefs *
2341  sizeof(*s->exp_buffer), alloc_fail);
2342  FF_ALLOC_OR_GOTO(avctx, s->grouped_exp_buffer, channel_blocks * 128 *
2343  sizeof(*s->grouped_exp_buffer), alloc_fail);
2344  FF_ALLOC_OR_GOTO(avctx, s->psd_buffer, total_coefs *
2345  sizeof(*s->psd_buffer), alloc_fail);
2346  FF_ALLOC_OR_GOTO(avctx, s->band_psd_buffer, channel_blocks * 64 *
2347  sizeof(*s->band_psd_buffer), alloc_fail);
2348  FF_ALLOC_OR_GOTO(avctx, s->mask_buffer, channel_blocks * 64 *
2349  sizeof(*s->mask_buffer), alloc_fail);
2350  FF_ALLOC_OR_GOTO(avctx, s->qmant_buffer, total_coefs *
2351  sizeof(*s->qmant_buffer), alloc_fail);
2352  if (s->cpl_enabled) {
2353  FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_exp_buffer, channel_blocks * 16 *
2354  sizeof(*s->cpl_coord_exp_buffer), alloc_fail);
2355  FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_mant_buffer, channel_blocks * 16 *
2356  sizeof(*s->cpl_coord_mant_buffer), alloc_fail);
2357  }
2358  for (blk = 0; blk < s->num_blocks; blk++) {
2359  AC3Block *block = &s->blocks[blk];
2360  FF_ALLOCZ_OR_GOTO(avctx, block->mdct_coef, channels * sizeof(*block->mdct_coef),
2361  alloc_fail);
2362  FF_ALLOCZ_OR_GOTO(avctx, block->exp, channels * sizeof(*block->exp),
2363  alloc_fail);
2364  FF_ALLOCZ_OR_GOTO(avctx, block->grouped_exp, channels * sizeof(*block->grouped_exp),
2365  alloc_fail);
2366  FF_ALLOCZ_OR_GOTO(avctx, block->psd, channels * sizeof(*block->psd),
2367  alloc_fail);
2368  FF_ALLOCZ_OR_GOTO(avctx, block->band_psd, channels * sizeof(*block->band_psd),
2369  alloc_fail);
2370  FF_ALLOCZ_OR_GOTO(avctx, block->mask, channels * sizeof(*block->mask),
2371  alloc_fail);
2372  FF_ALLOCZ_OR_GOTO(avctx, block->qmant, channels * sizeof(*block->qmant),
2373  alloc_fail);
2374  if (s->cpl_enabled) {
2375  FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_exp, channels * sizeof(*block->cpl_coord_exp),
2376  alloc_fail);
2377  FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_mant, channels * sizeof(*block->cpl_coord_mant),
2378  alloc_fail);
2379  }
2380 
2381  for (ch = 0; ch < channels; ch++) {
2382  /* arrangement: block, channel, coeff */
2383  block->grouped_exp[ch] = &s->grouped_exp_buffer[128 * (blk * channels + ch)];
2384  block->psd[ch] = &s->psd_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2385  block->band_psd[ch] = &s->band_psd_buffer [64 * (blk * channels + ch)];
2386  block->mask[ch] = &s->mask_buffer [64 * (blk * channels + ch)];
2387  block->qmant[ch] = &s->qmant_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2388  if (s->cpl_enabled) {
2389  block->cpl_coord_exp[ch] = &s->cpl_coord_exp_buffer [16 * (blk * channels + ch)];
2390  block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16 * (blk * channels + ch)];
2391  }
2392 
2393  /* arrangement: channel, block, coeff */
2394  block->exp[ch] = &s->exp_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2395  block->mdct_coef[ch] = &s->mdct_coef_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2396  }
2397  }
2398 
2399  if (!s->fixed_point) {
2400  FF_ALLOCZ_OR_GOTO(avctx, s->fixed_coef_buffer, total_coefs *
2401  sizeof(*s->fixed_coef_buffer), alloc_fail);
2402  for (blk = 0; blk < s->num_blocks; blk++) {
2403  AC3Block *block = &s->blocks[blk];
2404  FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
2405  sizeof(*block->fixed_coef), alloc_fail);
2406  for (ch = 0; ch < channels; ch++)
2407  block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2408  }
2409  } else {
2410  for (blk = 0; blk < s->num_blocks; blk++) {
2411  AC3Block *block = &s->blocks[blk];
2412  FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
2413  sizeof(*block->fixed_coef), alloc_fail);
2414  for (ch = 0; ch < channels; ch++)
2415  block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
2416  }
2417  }
2418 
2419  return 0;
2420 alloc_fail:
2421  return AVERROR(ENOMEM);
2422 }
2423 
2424 
2426 {
2427  AC3EncodeContext *s = avctx->priv_data;
2428  int ret, frame_size_58;
2429 
2430  s->avctx = avctx;
2431 
2432  s->eac3 = avctx->codec_id == AV_CODEC_ID_EAC3;
2433 
2435 
2436  ret = validate_options(s);
2437  if (ret)
2438  return ret;
2439 
2440  avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
2441  avctx->delay = AC3_BLOCK_SIZE;
2442 
2443  s->bitstream_mode = avctx->audio_service_type;
2445  s->bitstream_mode = 0x7;
2446 
2447  s->bits_written = 0;
2448  s->samples_written = 0;
2449 
2450  /* calculate crc_inv for both possible frame sizes */
2451  frame_size_58 = (( s->frame_size >> 2) + ( s->frame_size >> 4)) << 1;
2452  s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2453  if (s->bit_alloc.sr_code == 1) {
2454  frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
2455  s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2456  }
2457 
2458  /* set function pointers */
2463  } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {
2467  }
2468  if (CONFIG_EAC3_ENCODER && s->eac3)
2470  else
2472 
2473  set_bandwidth(s);
2474 
2475  exponent_init(s);
2476 
2477  bit_alloc_init(s);
2478 
2479  ret = s->mdct_init(s);
2480  if (ret)
2481  goto init_fail;
2482 
2483  ret = allocate_buffers(s);
2484  if (ret)
2485  goto init_fail;
2486 
2487 #if FF_API_OLD_ENCODE_AUDIO
2488  avctx->coded_frame= avcodec_alloc_frame();
2489  if (!avctx->coded_frame) {
2490  ret = AVERROR(ENOMEM);
2491  goto init_fail;
2492  }
2493 #endif
2494 
2495  ff_dsputil_init(&s->dsp, avctx);
2498 
2499  dprint_options(s);
2500 
2501  return 0;
2502 init_fail:
2503  ff_ac3_encode_close(avctx);
2504  return ret;
2505 }
#define CONFIG_EAC3_ENCODER
Definition: config.h:893
static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
Initialize mantissa counts.
Definition: ac3enc.c:994
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:32
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:890
av_cold void ff_dsputil_init(DSPContext *c, AVCodecContext *avctx)
Definition: dsputil.c:2656
#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:2065
static void ac3_output_frame_header(AC3EncodeContext *s)
Definition: ac3enc.c:1330
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:345
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:90
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:174
static void compute_exp_strategy(AC3EncodeContext *s)
Definition: ac3enc.c:356
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:1180
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:73
#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
AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2725
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:2323
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
static void bit_alloc_init(AC3EncodeContext *s)
Definition: ac3enc.c:757
void ff_ac3_process_exponents(AC3EncodeContext *s)
Calculate final exponents from the supplied MDCT coefficients and exponent shift. ...
Definition: ac3enc.c:635
#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:171
#define EXP_D25
Definition: ac3.h:49
static const float cmixlev_options[CMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:53
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:545
static void extract_exponents(AC3EncodeContext *s)
Definition: ac3enc.c:326
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:151
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:2179
int ff_ac3_validate_metadata(AC3EncodeContext *s)
Validate metadata options as set by AVOption system.
Definition: ac3enc.c:1834
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:62
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:2112
uint8_t
int(* allocate_sample_buffers)(struct AC3EncodeContext *s)
Definition: ac3enc.h:257
#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:793
AVOptions.
static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:63
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:76
#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:2253
#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:145
av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
Finalize encoding and free any memory allocated by the encoder.
Definition: ac3enc.c:2018
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:42
#define CRC16_POLY
CRC-16 Polynomial.
Definition: ac3enc.c:1576
uint8_t ** exp
original exponents
Definition: ac3enc.h:131
int num_rematrixing_bands
number of rematrixing bands
Definition: ac3enc.h:141
static av_cold int validate_options(AC3EncodeContext *s)
Definition: ac3enc.c:2110
#define LOCAL_ALIGNED_16(t, v,...)
Definition: dsputil.h:602
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:1062
void ff_ac3_fixed_mdct_end(AC3EncodeContext *s)
static void dprint_options(AC3EncodeContext *s)
Definition: ac3enc.c:1677
int lfe_channel
channel index of the LFE channel
Definition: ac3enc.h:190
int mant2_cnt
Definition: ac3enc.c:49
#define CONFIG_AC3_FIXED_ENCODER
Definition: config.h:891
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:340
static av_cold void exponent_init(AC3EncodeContext *s)
Definition: ac3enc.c:304
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:1204
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:48
#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:48
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
struct AC3Mant AC3Mant
const uint64_t ff_ac3_channel_layouts[19]
List of supported channel layouts.
Definition: ac3enc.c:79
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:201
static int sym_quant(int c, int e, int levels)
Symmetric quantization on 'levels' levels.
Definition: ac3enc.c:1164
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
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:422
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:1434
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:42
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:146
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:136
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:67
int cpl_enabled
coupling enabled for all frames
Definition: ac3enc.h:209
static void output_frame_end(AC3EncodeContext *s)
Definition: ac3enc.c:1613
#define EXTMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:62
Definition: ac3enc.c:47
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2165
#define LEVEL_MINUS_4POINT5DB
Definition: ac3.h:57
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:70
#define AC3_BLOCK_SIZE
Definition: ac3.h:35
static void output_audio_block(AC3EncodeContext *s, int blk)
Definition: ac3enc.c:1386
const uint16_t ff_ac3_bitrate_tab[19]
Definition: ac3tab.c:130
static int count_mantissa_bits(AC3EncodeContext *s)
Definition: ac3enc.c:1036
#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
AVFrame * avcodec_alloc_frame(void)
Allocate an AVFrame and set its fields to default values.
Definition: utils.c:616
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:1144
#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:1404
audio channel layout utility functions
static DCTELEM block[64]
Definition: dct-test.c:169
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
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:107
float loro_center_mix_level
Definition: ac3enc.h:109
av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
Definition: ac3dsp.c:199
int mant4_cnt
mantissa counts for bap=1,2,4
Definition: ac3enc.c:49
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_eac3_exponent_init(void)
Initialize E-AC-3 exponent tables.
Definition: eac3enc.c:46
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:181
#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
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:2124
#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:52
#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:122
external API header
int audio_production_info
Definition: ac3enc.h:100
enum AVCodecID codec_id
Definition: avcodec.h:1350
int sample_rate
samples per second
Definition: avcodec.h:2104
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:140
main external API structure.
Definition: avcodec.h:1339
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:1579
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:1792
static int validate_float_option(float v, const float *v_list, int v_list_size)
Definition: ac3enc.c:1794
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
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:1662
static void count_frame_bits_fixed(AC3EncodeContext *s)
Definition: ac3enc.c:651
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:49
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:1301
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:495
#define CMIXLEV_NUM_OPTIONS
Definition: ac3enc.c:52
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:969
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:57
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:86
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:1810
#define FF_ALLOC_OR_GOTO(ctx, p, size, label)
Definition: internal.h:60
me_cmp_func sad[6]
Definition: dsputil.h:224
static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS]
Definition: ac3enc.c:58
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:52
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
DSP utils.
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:1382
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:2148
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:1016
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:2105
#define AC3ENC_OPT_NOT_INDICATED
Definition: ac3enc.h:77
static int cbr_bit_allocation(AC3EncodeContext *s)
Definition: ac3enc.c:1093
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:1596
void ff_ac3_apply_rematrixing(AC3EncodeContext *s)
Apply stereo rematrixing to coefficients based on rematrixing flags.
Definition: ac3enc.c:270
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
static void bit_alloc_masking(AC3EncodeContext *s)
Definition: ac3enc.c:939
int ff_ac3_fixed_mdct_init(AC3EncodeContext *s)
void avpriv_float_dsp_init(AVFloatDSPContext *fdsp, int bit_exact)
Initialize a float DSP context.
Definition: float_dsp.c:55
void ff_ac3_group_exponents(AC3EncodeContext *s)
Group exponents.
Definition: ac3enc.c:577
const uint16_t ff_ac3_db_per_bit_tab[4]
Definition: ac3tab.c:290
int16_t * qmant2_ptr
Definition: ac3enc.c:48
#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:199
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:1497
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:69
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
if(!(ptr_align%ac->ptr_align)&&samples_align >=aligned_len)
av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
Definition: ac3enc.c:2425
bitstream writer API