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aacsbr.c
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1 /*
2  * AAC Spectral Band Replication decoding functions
3  * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
4  * Copyright (c) 2009-2010 Alex Converse <alex.converse@gmail.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * AAC Spectral Band Replication decoding functions
26  * @author Robert Swain ( rob opendot cl )
27  */
28 
29 #include "aac.h"
30 #include "sbr.h"
31 #include "aacsbr.h"
32 #include "aacsbrdata.h"
33 #include "fft.h"
34 #include "aacps.h"
35 #include "sbrdsp.h"
36 #include "libavutil/libm.h"
37 #include "libavutil/avassert.h"
38 
39 #include <stdint.h>
40 #include <float.h>
41 #include <math.h>
42 
43 #define ENVELOPE_ADJUSTMENT_OFFSET 2
44 #define NOISE_FLOOR_OFFSET 6.0f
45 
46 /**
47  * SBR VLC tables
48  */
49 enum {
50  T_HUFFMAN_ENV_1_5DB,
51  F_HUFFMAN_ENV_1_5DB,
52  T_HUFFMAN_ENV_BAL_1_5DB,
53  F_HUFFMAN_ENV_BAL_1_5DB,
54  T_HUFFMAN_ENV_3_0DB,
55  F_HUFFMAN_ENV_3_0DB,
56  T_HUFFMAN_ENV_BAL_3_0DB,
57  F_HUFFMAN_ENV_BAL_3_0DB,
58  T_HUFFMAN_NOISE_3_0DB,
59  T_HUFFMAN_NOISE_BAL_3_0DB,
60 };
61 
62 /**
63  * bs_frame_class - frame class of current SBR frame (14496-3 sp04 p98)
64  */
65 enum {
66  FIXFIX,
67  FIXVAR,
68  VARFIX,
69  VARVAR,
70 };
71 
72 enum {
73  EXTENSION_ID_PS = 2,
74 };
75 
76 static VLC vlc_sbr[10];
77 static const int8_t vlc_sbr_lav[10] =
78  { 60, 60, 24, 24, 31, 31, 12, 12, 31, 12 };
79 
80 #define SBR_INIT_VLC_STATIC(num, size) \
81  INIT_VLC_STATIC(&vlc_sbr[num], 9, sbr_tmp[num].table_size / sbr_tmp[num].elem_size, \
82  sbr_tmp[num].sbr_bits , 1, 1, \
83  sbr_tmp[num].sbr_codes, sbr_tmp[num].elem_size, sbr_tmp[num].elem_size, \
84  size)
85 
86 #define SBR_VLC_ROW(name) \
87  { name ## _codes, name ## _bits, sizeof(name ## _codes), sizeof(name ## _codes[0]) }
88 
89 av_cold void ff_aac_sbr_init(void)
90 {
91  int n;
92  static const struct {
93  const void *sbr_codes, *sbr_bits;
94  const unsigned int table_size, elem_size;
95  } sbr_tmp[] = {
96  SBR_VLC_ROW(t_huffman_env_1_5dB),
97  SBR_VLC_ROW(f_huffman_env_1_5dB),
98  SBR_VLC_ROW(t_huffman_env_bal_1_5dB),
99  SBR_VLC_ROW(f_huffman_env_bal_1_5dB),
100  SBR_VLC_ROW(t_huffman_env_3_0dB),
101  SBR_VLC_ROW(f_huffman_env_3_0dB),
102  SBR_VLC_ROW(t_huffman_env_bal_3_0dB),
103  SBR_VLC_ROW(f_huffman_env_bal_3_0dB),
104  SBR_VLC_ROW(t_huffman_noise_3_0dB),
105  SBR_VLC_ROW(t_huffman_noise_bal_3_0dB),
106  };
107 
108  // SBR VLC table initialization
109  SBR_INIT_VLC_STATIC(0, 1098);
110  SBR_INIT_VLC_STATIC(1, 1092);
111  SBR_INIT_VLC_STATIC(2, 768);
112  SBR_INIT_VLC_STATIC(3, 1026);
113  SBR_INIT_VLC_STATIC(4, 1058);
114  SBR_INIT_VLC_STATIC(5, 1052);
115  SBR_INIT_VLC_STATIC(6, 544);
116  SBR_INIT_VLC_STATIC(7, 544);
117  SBR_INIT_VLC_STATIC(8, 592);
118  SBR_INIT_VLC_STATIC(9, 512);
119 
120  for (n = 1; n < 320; n++)
121  sbr_qmf_window_us[320 + n] = sbr_qmf_window_us[320 - n];
122  sbr_qmf_window_us[384] = -sbr_qmf_window_us[384];
123  sbr_qmf_window_us[512] = -sbr_qmf_window_us[512];
124 
125  for (n = 0; n < 320; n++)
126  sbr_qmf_window_ds[n] = sbr_qmf_window_us[2*n];
127 
128  ff_ps_init();
129 }
130 
131 /** Places SBR in pure upsampling mode. */
132 static void sbr_turnoff(SpectralBandReplication *sbr) {
133  sbr->start = 0;
134  // Init defults used in pure upsampling mode
135  sbr->kx[1] = 32; //Typo in spec, kx' inits to 32
136  sbr->m[1] = 0;
137  // Reset values for first SBR header
138  sbr->data[0].e_a[1] = sbr->data[1].e_a[1] = -1;
139  memset(&sbr->spectrum_params, -1, sizeof(SpectrumParameters));
140 }
141 
142 av_cold void ff_aac_sbr_ctx_init(AACContext *ac, SpectralBandReplication *sbr)
143 {
144  if(sbr->mdct.mdct_bits)
145  return;
146  sbr->kx[0] = sbr->kx[1];
147  sbr_turnoff(sbr);
148  sbr->data[0].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
149  sbr->data[1].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
150  /* SBR requires samples to be scaled to +/-32768.0 to work correctly.
151  * mdct scale factors are adjusted to scale up from +/-1.0 at analysis
152  * and scale back down at synthesis. */
153  ff_mdct_init(&sbr->mdct, 7, 1, 1.0 / (64 * 32768.0));
154  ff_mdct_init(&sbr->mdct_ana, 7, 1, -2.0 * 32768.0);
155  ff_ps_ctx_init(&sbr->ps);
156  ff_sbrdsp_init(&sbr->dsp);
157 }
158 
159 av_cold void ff_aac_sbr_ctx_close(SpectralBandReplication *sbr)
160 {
161  ff_mdct_end(&sbr->mdct);
162  ff_mdct_end(&sbr->mdct_ana);
163 }
164 
165 static int qsort_comparison_function_int16(const void *a, const void *b)
166 {
167  return *(const int16_t *)a - *(const int16_t *)b;
168 }
169 
170 static inline int in_table_int16(const int16_t *table, int last_el, int16_t needle)
171 {
172  int i;
173  for (i = 0; i <= last_el; i++)
174  if (table[i] == needle)
175  return 1;
176  return 0;
177 }
178 
179 /// Limiter Frequency Band Table (14496-3 sp04 p198)
180 static void sbr_make_f_tablelim(SpectralBandReplication *sbr)
181 {
182  int k;
183  if (sbr->bs_limiter_bands > 0) {
184  static const float bands_warped[3] = { 1.32715174233856803909f, //2^(0.49/1.2)
185  1.18509277094158210129f, //2^(0.49/2)
186  1.11987160404675912501f }; //2^(0.49/3)
187  const float lim_bands_per_octave_warped = bands_warped[sbr->bs_limiter_bands - 1];
188  int16_t patch_borders[7];
189  uint16_t *in = sbr->f_tablelim + 1, *out = sbr->f_tablelim;
190 
191  patch_borders[0] = sbr->kx[1];
192  for (k = 1; k <= sbr->num_patches; k++)
193  patch_borders[k] = patch_borders[k-1] + sbr->patch_num_subbands[k-1];
194 
195  memcpy(sbr->f_tablelim, sbr->f_tablelow,
196  (sbr->n[0] + 1) * sizeof(sbr->f_tablelow[0]));
197  if (sbr->num_patches > 1)
198  memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
199  (sbr->num_patches - 1) * sizeof(patch_borders[0]));
200 
201  qsort(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
202  sizeof(sbr->f_tablelim[0]),
203  qsort_comparison_function_int16);
204 
205  sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
206  while (out < sbr->f_tablelim + sbr->n_lim) {
207  if (*in >= *out * lim_bands_per_octave_warped) {
208  *++out = *in++;
209  } else if (*in == *out ||
210  !in_table_int16(patch_borders, sbr->num_patches, *in)) {
211  in++;
212  sbr->n_lim--;
213  } else if (!in_table_int16(patch_borders, sbr->num_patches, *out)) {
214  *out = *in++;
215  sbr->n_lim--;
216  } else {
217  *++out = *in++;
218  }
219  }
220  } else {
221  sbr->f_tablelim[0] = sbr->f_tablelow[0];
222  sbr->f_tablelim[1] = sbr->f_tablelow[sbr->n[0]];
223  sbr->n_lim = 1;
224  }
225 }
226 
227 static unsigned int read_sbr_header(SpectralBandReplication *sbr, GetBitContext *gb)
228 {
229  unsigned int cnt = get_bits_count(gb);
230  uint8_t bs_header_extra_1;
231  uint8_t bs_header_extra_2;
232  int old_bs_limiter_bands = sbr->bs_limiter_bands;
233  SpectrumParameters old_spectrum_params;
234 
235  sbr->start = 1;
236 
237  // Save last spectrum parameters variables to compare to new ones
238  memcpy(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters));
239 
240  sbr->bs_amp_res_header = get_bits1(gb);
241  sbr->spectrum_params.bs_start_freq = get_bits(gb, 4);
242  sbr->spectrum_params.bs_stop_freq = get_bits(gb, 4);
243  sbr->spectrum_params.bs_xover_band = get_bits(gb, 3);
244  skip_bits(gb, 2); // bs_reserved
245 
246  bs_header_extra_1 = get_bits1(gb);
247  bs_header_extra_2 = get_bits1(gb);
248 
249  if (bs_header_extra_1) {
250  sbr->spectrum_params.bs_freq_scale = get_bits(gb, 2);
251  sbr->spectrum_params.bs_alter_scale = get_bits1(gb);
252  sbr->spectrum_params.bs_noise_bands = get_bits(gb, 2);
253  } else {
254  sbr->spectrum_params.bs_freq_scale = 2;
255  sbr->spectrum_params.bs_alter_scale = 1;
256  sbr->spectrum_params.bs_noise_bands = 2;
257  }
258 
259  // Check if spectrum parameters changed
260  if (memcmp(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters)))
261  sbr->reset = 1;
262 
263  if (bs_header_extra_2) {
264  sbr->bs_limiter_bands = get_bits(gb, 2);
265  sbr->bs_limiter_gains = get_bits(gb, 2);
266  sbr->bs_interpol_freq = get_bits1(gb);
267  sbr->bs_smoothing_mode = get_bits1(gb);
268  } else {
269  sbr->bs_limiter_bands = 2;
270  sbr->bs_limiter_gains = 2;
271  sbr->bs_interpol_freq = 1;
272  sbr->bs_smoothing_mode = 1;
273  }
274 
275  if (sbr->bs_limiter_bands != old_bs_limiter_bands && !sbr->reset)
276  sbr_make_f_tablelim(sbr);
277 
278  return get_bits_count(gb) - cnt;
279 }
280 
281 static int array_min_int16(const int16_t *array, int nel)
282 {
283  int i, min = array[0];
284  for (i = 1; i < nel; i++)
285  min = FFMIN(array[i], min);
286  return min;
287 }
288 
289 static void make_bands(int16_t* bands, int start, int stop, int num_bands)
290 {
291  int k, previous, present;
292  float base, prod;
293 
294  base = powf((float)stop / start, 1.0f / num_bands);
295  prod = start;
296  previous = start;
297 
298  for (k = 0; k < num_bands-1; k++) {
299  prod *= base;
300  present = lrintf(prod);
301  bands[k] = present - previous;
302  previous = present;
303  }
304  bands[num_bands-1] = stop - previous;
305 }
306 
307 static int check_n_master(AVCodecContext *avctx, int n_master, int bs_xover_band)
308 {
309  // Requirements (14496-3 sp04 p205)
310  if (n_master <= 0) {
311  av_log(avctx, AV_LOG_ERROR, "Invalid n_master: %d\n", n_master);
312  return -1;
313  }
314  if (bs_xover_band >= n_master) {
315  av_log(avctx, AV_LOG_ERROR,
316  "Invalid bitstream, crossover band index beyond array bounds: %d\n",
317  bs_xover_band);
318  return -1;
319  }
320  return 0;
321 }
322 
323 /// Master Frequency Band Table (14496-3 sp04 p194)
324 static int sbr_make_f_master(AACContext *ac, SpectralBandReplication *sbr,
325  SpectrumParameters *spectrum)
326 {
327  unsigned int temp, max_qmf_subbands;
328  unsigned int start_min, stop_min;
329  int k;
330  const int8_t *sbr_offset_ptr;
331  int16_t stop_dk[13];
332 
333  if (sbr->sample_rate < 32000) {
334  temp = 3000;
335  } else if (sbr->sample_rate < 64000) {
336  temp = 4000;
337  } else
338  temp = 5000;
339 
340  switch (sbr->sample_rate) {
341  case 16000:
342  sbr_offset_ptr = sbr_offset[0];
343  break;
344  case 22050:
345  sbr_offset_ptr = sbr_offset[1];
346  break;
347  case 24000:
348  sbr_offset_ptr = sbr_offset[2];
349  break;
350  case 32000:
351  sbr_offset_ptr = sbr_offset[3];
352  break;
353  case 44100: case 48000: case 64000:
354  sbr_offset_ptr = sbr_offset[4];
355  break;
356  case 88200: case 96000: case 128000: case 176400: case 192000:
357  sbr_offset_ptr = sbr_offset[5];
358  break;
359  default:
360  av_log(ac->avctx, AV_LOG_ERROR,
361  "Unsupported sample rate for SBR: %d\n", sbr->sample_rate);
362  return -1;
363  }
364 
365  start_min = ((temp << 7) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
366  stop_min = ((temp << 8) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
367 
368  sbr->k[0] = start_min + sbr_offset_ptr[spectrum->bs_start_freq];
369 
370  if (spectrum->bs_stop_freq < 14) {
371  sbr->k[2] = stop_min;
372  make_bands(stop_dk, stop_min, 64, 13);
373  qsort(stop_dk, 13, sizeof(stop_dk[0]), qsort_comparison_function_int16);
374  for (k = 0; k < spectrum->bs_stop_freq; k++)
375  sbr->k[2] += stop_dk[k];
376  } else if (spectrum->bs_stop_freq == 14) {
377  sbr->k[2] = 2*sbr->k[0];
378  } else if (spectrum->bs_stop_freq == 15) {
379  sbr->k[2] = 3*sbr->k[0];
380  } else {
381  av_log(ac->avctx, AV_LOG_ERROR,
382  "Invalid bs_stop_freq: %d\n", spectrum->bs_stop_freq);
383  return -1;
384  }
385  sbr->k[2] = FFMIN(64, sbr->k[2]);
386 
387  // Requirements (14496-3 sp04 p205)
388  if (sbr->sample_rate <= 32000) {
389  max_qmf_subbands = 48;
390  } else if (sbr->sample_rate == 44100) {
391  max_qmf_subbands = 35;
392  } else if (sbr->sample_rate >= 48000)
393  max_qmf_subbands = 32;
394 
395  if (sbr->k[2] - sbr->k[0] > max_qmf_subbands) {
396  av_log(ac->avctx, AV_LOG_ERROR,
397  "Invalid bitstream, too many QMF subbands: %d\n", sbr->k[2] - sbr->k[0]);
398  return -1;
399  }
400 
401  if (!spectrum->bs_freq_scale) {
402  int dk, k2diff;
403 
404  dk = spectrum->bs_alter_scale + 1;
405  sbr->n_master = ((sbr->k[2] - sbr->k[0] + (dk&2)) >> dk) << 1;
406  if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
407  return -1;
408 
409  for (k = 1; k <= sbr->n_master; k++)
410  sbr->f_master[k] = dk;
411 
412  k2diff = sbr->k[2] - sbr->k[0] - sbr->n_master * dk;
413  if (k2diff < 0) {
414  sbr->f_master[1]--;
415  sbr->f_master[2]-= (k2diff < -1);
416  } else if (k2diff) {
417  sbr->f_master[sbr->n_master]++;
418  }
419 
420  sbr->f_master[0] = sbr->k[0];
421  for (k = 1; k <= sbr->n_master; k++)
422  sbr->f_master[k] += sbr->f_master[k - 1];
423 
424  } else {
425  int half_bands = 7 - spectrum->bs_freq_scale; // bs_freq_scale = {1,2,3}
426  int two_regions, num_bands_0;
427  int vdk0_max, vdk1_min;
428  int16_t vk0[49];
429 
430  if (49 * sbr->k[2] > 110 * sbr->k[0]) {
431  two_regions = 1;
432  sbr->k[1] = 2 * sbr->k[0];
433  } else {
434  two_regions = 0;
435  sbr->k[1] = sbr->k[2];
436  }
437 
438  num_bands_0 = lrintf(half_bands * log2f(sbr->k[1] / (float)sbr->k[0])) * 2;
439 
440  if (num_bands_0 <= 0) { // Requirements (14496-3 sp04 p205)
441  av_log(ac->avctx, AV_LOG_ERROR, "Invalid num_bands_0: %d\n", num_bands_0);
442  return -1;
443  }
444 
445  vk0[0] = 0;
446 
447  make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
448 
449  qsort(vk0 + 1, num_bands_0, sizeof(vk0[1]), qsort_comparison_function_int16);
450  vdk0_max = vk0[num_bands_0];
451 
452  vk0[0] = sbr->k[0];
453  for (k = 1; k <= num_bands_0; k++) {
454  if (vk0[k] <= 0) { // Requirements (14496-3 sp04 p205)
455  av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk0[%d]: %d\n", k, vk0[k]);
456  return -1;
457  }
458  vk0[k] += vk0[k-1];
459  }
460 
461  if (two_regions) {
462  int16_t vk1[49];
463  float invwarp = spectrum->bs_alter_scale ? 0.76923076923076923077f
464  : 1.0f; // bs_alter_scale = {0,1}
465  int num_bands_1 = lrintf(half_bands * invwarp *
466  log2f(sbr->k[2] / (float)sbr->k[1])) * 2;
467 
468  make_bands(vk1+1, sbr->k[1], sbr->k[2], num_bands_1);
469 
470  vdk1_min = array_min_int16(vk1 + 1, num_bands_1);
471 
472  if (vdk1_min < vdk0_max) {
473  int change;
474  qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
475  change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1]) >> 1);
476  vk1[1] += change;
477  vk1[num_bands_1] -= change;
478  }
479 
480  qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
481 
482  vk1[0] = sbr->k[1];
483  for (k = 1; k <= num_bands_1; k++) {
484  if (vk1[k] <= 0) { // Requirements (14496-3 sp04 p205)
485  av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk1[%d]: %d\n", k, vk1[k]);
486  return -1;
487  }
488  vk1[k] += vk1[k-1];
489  }
490 
491  sbr->n_master = num_bands_0 + num_bands_1;
492  if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
493  return -1;
494  memcpy(&sbr->f_master[0], vk0,
495  (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
496  memcpy(&sbr->f_master[num_bands_0 + 1], vk1 + 1,
497  num_bands_1 * sizeof(sbr->f_master[0]));
498 
499  } else {
500  sbr->n_master = num_bands_0;
501  if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
502  return -1;
503  memcpy(sbr->f_master, vk0, (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
504  }
505  }
506 
507  return 0;
508 }
509 
510 /// High Frequency Generation - Patch Construction (14496-3 sp04 p216 fig. 4.46)
511 static int sbr_hf_calc_npatches(AACContext *ac, SpectralBandReplication *sbr)
512 {
513  int i, k, sb = 0;
514  int msb = sbr->k[0];
515  int usb = sbr->kx[1];
516  int goal_sb = ((1000 << 11) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
517 
518  sbr->num_patches = 0;
519 
520  if (goal_sb < sbr->kx[1] + sbr->m[1]) {
521  for (k = 0; sbr->f_master[k] < goal_sb; k++) ;
522  } else
523  k = sbr->n_master;
524 
525  do {
526  int odd = 0;
527  for (i = k; i == k || sb > (sbr->k[0] - 1 + msb - odd); i--) {
528  sb = sbr->f_master[i];
529  odd = (sb + sbr->k[0]) & 1;
530  }
531 
532  // Requirements (14496-3 sp04 p205) sets the maximum number of patches to 5.
533  // After this check the final number of patches can still be six which is
534  // illegal however the Coding Technologies decoder check stream has a final
535  // count of 6 patches
536  if (sbr->num_patches > 5) {
537  av_log(ac->avctx, AV_LOG_ERROR, "Too many patches: %d\n", sbr->num_patches);
538  return -1;
539  }
540 
541  sbr->patch_num_subbands[sbr->num_patches] = FFMAX(sb - usb, 0);
542  sbr->patch_start_subband[sbr->num_patches] = sbr->k[0] - odd - sbr->patch_num_subbands[sbr->num_patches];
543 
544  if (sbr->patch_num_subbands[sbr->num_patches] > 0) {
545  usb = sb;
546  msb = sb;
547  sbr->num_patches++;
548  } else
549  msb = sbr->kx[1];
550 
551  if (sbr->f_master[k] - sb < 3)
552  k = sbr->n_master;
553  } while (sb != sbr->kx[1] + sbr->m[1]);
554 
555  if (sbr->num_patches > 1 && sbr->patch_num_subbands[sbr->num_patches-1] < 3)
556  sbr->num_patches--;
557 
558  return 0;
559 }
560 
561 /// Derived Frequency Band Tables (14496-3 sp04 p197)
562 static int sbr_make_f_derived(AACContext *ac, SpectralBandReplication *sbr)
563 {
564  int k, temp;
565 
566  sbr->n[1] = sbr->n_master - sbr->spectrum_params.bs_xover_band;
567  sbr->n[0] = (sbr->n[1] + 1) >> 1;
568 
569  memcpy(sbr->f_tablehigh, &sbr->f_master[sbr->spectrum_params.bs_xover_band],
570  (sbr->n[1] + 1) * sizeof(sbr->f_master[0]));
571  sbr->m[1] = sbr->f_tablehigh[sbr->n[1]] - sbr->f_tablehigh[0];
572  sbr->kx[1] = sbr->f_tablehigh[0];
573 
574  // Requirements (14496-3 sp04 p205)
575  if (sbr->kx[1] + sbr->m[1] > 64) {
576  av_log(ac->avctx, AV_LOG_ERROR,
577  "Stop frequency border too high: %d\n", sbr->kx[1] + sbr->m[1]);
578  return -1;
579  }
580  if (sbr->kx[1] > 32) {
581  av_log(ac->avctx, AV_LOG_ERROR, "Start frequency border too high: %d\n", sbr->kx[1]);
582  return -1;
583  }
584 
585  sbr->f_tablelow[0] = sbr->f_tablehigh[0];
586  temp = sbr->n[1] & 1;
587  for (k = 1; k <= sbr->n[0]; k++)
588  sbr->f_tablelow[k] = sbr->f_tablehigh[2 * k - temp];
589 
590  sbr->n_q = FFMAX(1, lrintf(sbr->spectrum_params.bs_noise_bands *
591  log2f(sbr->k[2] / (float)sbr->kx[1]))); // 0 <= bs_noise_bands <= 3
592  if (sbr->n_q > 5) {
593  av_log(ac->avctx, AV_LOG_ERROR, "Too many noise floor scale factors: %d\n", sbr->n_q);
594  return -1;
595  }
596 
597  sbr->f_tablenoise[0] = sbr->f_tablelow[0];
598  temp = 0;
599  for (k = 1; k <= sbr->n_q; k++) {
600  temp += (sbr->n[0] - temp) / (sbr->n_q + 1 - k);
601  sbr->f_tablenoise[k] = sbr->f_tablelow[temp];
602  }
603 
604  if (sbr_hf_calc_npatches(ac, sbr) < 0)
605  return -1;
606 
607  sbr_make_f_tablelim(sbr);
608 
609  sbr->data[0].f_indexnoise = 0;
610  sbr->data[1].f_indexnoise = 0;
611 
612  return 0;
613 }
614 
615 static av_always_inline void get_bits1_vector(GetBitContext *gb, uint8_t *vec,
616  int elements)
617 {
618  int i;
619  for (i = 0; i < elements; i++) {
620  vec[i] = get_bits1(gb);
621  }
622 }
623 
624 /** ceil(log2(index+1)) */
625 static const int8_t ceil_log2[] = {
626  0, 1, 2, 2, 3, 3,
627 };
628 
629 static int read_sbr_grid(AACContext *ac, SpectralBandReplication *sbr,
630  GetBitContext *gb, SBRData *ch_data)
631 {
632  int i;
633  unsigned bs_pointer = 0;
634  // frameLengthFlag ? 15 : 16; 960 sample length frames unsupported; this value is numTimeSlots
635  int abs_bord_trail = 16;
636  int num_rel_lead, num_rel_trail;
637  unsigned bs_num_env_old = ch_data->bs_num_env;
638 
639  ch_data->bs_freq_res[0] = ch_data->bs_freq_res[ch_data->bs_num_env];
640  ch_data->bs_amp_res = sbr->bs_amp_res_header;
641  ch_data->t_env_num_env_old = ch_data->t_env[bs_num_env_old];
642 
643  switch (ch_data->bs_frame_class = get_bits(gb, 2)) {
644  case FIXFIX:
645  ch_data->bs_num_env = 1 << get_bits(gb, 2);
646  num_rel_lead = ch_data->bs_num_env - 1;
647  if (ch_data->bs_num_env == 1)
648  ch_data->bs_amp_res = 0;
649 
650  if (ch_data->bs_num_env > 4) {
651  av_log(ac->avctx, AV_LOG_ERROR,
652  "Invalid bitstream, too many SBR envelopes in FIXFIX type SBR frame: %d\n",
653  ch_data->bs_num_env);
654  return -1;
655  }
656 
657  ch_data->t_env[0] = 0;
658  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
659 
660  abs_bord_trail = (abs_bord_trail + (ch_data->bs_num_env >> 1)) /
661  ch_data->bs_num_env;
662  for (i = 0; i < num_rel_lead; i++)
663  ch_data->t_env[i + 1] = ch_data->t_env[i] + abs_bord_trail;
664 
665  ch_data->bs_freq_res[1] = get_bits1(gb);
666  for (i = 1; i < ch_data->bs_num_env; i++)
667  ch_data->bs_freq_res[i + 1] = ch_data->bs_freq_res[1];
668  break;
669  case FIXVAR:
670  abs_bord_trail += get_bits(gb, 2);
671  num_rel_trail = get_bits(gb, 2);
672  ch_data->bs_num_env = num_rel_trail + 1;
673  ch_data->t_env[0] = 0;
674  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
675 
676  for (i = 0; i < num_rel_trail; i++)
677  ch_data->t_env[ch_data->bs_num_env - 1 - i] =
678  ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
679 
680  bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
681 
682  for (i = 0; i < ch_data->bs_num_env; i++)
683  ch_data->bs_freq_res[ch_data->bs_num_env - i] = get_bits1(gb);
684  break;
685  case VARFIX:
686  ch_data->t_env[0] = get_bits(gb, 2);
687  num_rel_lead = get_bits(gb, 2);
688  ch_data->bs_num_env = num_rel_lead + 1;
689  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
690 
691  for (i = 0; i < num_rel_lead; i++)
692  ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
693 
694  bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
695 
696  get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
697  break;
698  case VARVAR:
699  ch_data->t_env[0] = get_bits(gb, 2);
700  abs_bord_trail += get_bits(gb, 2);
701  num_rel_lead = get_bits(gb, 2);
702  num_rel_trail = get_bits(gb, 2);
703  ch_data->bs_num_env = num_rel_lead + num_rel_trail + 1;
704 
705  if (ch_data->bs_num_env > 5) {
706  av_log(ac->avctx, AV_LOG_ERROR,
707  "Invalid bitstream, too many SBR envelopes in VARVAR type SBR frame: %d\n",
708  ch_data->bs_num_env);
709  return -1;
710  }
711 
712  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
713 
714  for (i = 0; i < num_rel_lead; i++)
715  ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
716  for (i = 0; i < num_rel_trail; i++)
717  ch_data->t_env[ch_data->bs_num_env - 1 - i] =
718  ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
719 
720  bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
721 
722  get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
723  break;
724  }
725 
726  if (bs_pointer > ch_data->bs_num_env + 1) {
727  av_log(ac->avctx, AV_LOG_ERROR,
728  "Invalid bitstream, bs_pointer points to a middle noise border outside the time borders table: %d\n",
729  bs_pointer);
730  return -1;
731  }
732 
733  for (i = 1; i <= ch_data->bs_num_env; i++) {
734  if (ch_data->t_env[i-1] > ch_data->t_env[i]) {
735  av_log(ac->avctx, AV_LOG_ERROR, "Non monotone time borders\n");
736  return -1;
737  }
738  }
739 
740  ch_data->bs_num_noise = (ch_data->bs_num_env > 1) + 1;
741 
742  ch_data->t_q[0] = ch_data->t_env[0];
743  ch_data->t_q[ch_data->bs_num_noise] = ch_data->t_env[ch_data->bs_num_env];
744  if (ch_data->bs_num_noise > 1) {
745  unsigned int idx;
746  if (ch_data->bs_frame_class == FIXFIX) {
747  idx = ch_data->bs_num_env >> 1;
748  } else if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
749  idx = ch_data->bs_num_env - FFMAX((int)bs_pointer - 1, 1);
750  } else { // VARFIX
751  if (!bs_pointer)
752  idx = 1;
753  else if (bs_pointer == 1)
754  idx = ch_data->bs_num_env - 1;
755  else // bs_pointer > 1
756  idx = bs_pointer - 1;
757  }
758  ch_data->t_q[1] = ch_data->t_env[idx];
759  }
760 
761  ch_data->e_a[0] = -(ch_data->e_a[1] != bs_num_env_old); // l_APrev
762  ch_data->e_a[1] = -1;
763  if ((ch_data->bs_frame_class & 1) && bs_pointer) { // FIXVAR or VARVAR and bs_pointer != 0
764  ch_data->e_a[1] = ch_data->bs_num_env + 1 - bs_pointer;
765  } else if ((ch_data->bs_frame_class == 2) && (bs_pointer > 1)) // VARFIX and bs_pointer > 1
766  ch_data->e_a[1] = bs_pointer - 1;
767 
768  return 0;
769 }
770 
771 static void copy_sbr_grid(SBRData *dst, const SBRData *src) {
772  //These variables are saved from the previous frame rather than copied
773  dst->bs_freq_res[0] = dst->bs_freq_res[dst->bs_num_env];
774  dst->t_env_num_env_old = dst->t_env[dst->bs_num_env];
775  dst->e_a[0] = -(dst->e_a[1] != dst->bs_num_env);
776 
777  //These variables are read from the bitstream and therefore copied
778  memcpy(dst->bs_freq_res+1, src->bs_freq_res+1, sizeof(dst->bs_freq_res)-sizeof(*dst->bs_freq_res));
779  memcpy(dst->t_env, src->t_env, sizeof(dst->t_env));
780  memcpy(dst->t_q, src->t_q, sizeof(dst->t_q));
781  dst->bs_num_env = src->bs_num_env;
782  dst->bs_amp_res = src->bs_amp_res;
783  dst->bs_num_noise = src->bs_num_noise;
784  dst->bs_frame_class = src->bs_frame_class;
785  dst->e_a[1] = src->e_a[1];
786 }
787 
788 /// Read how the envelope and noise floor data is delta coded
789 static void read_sbr_dtdf(SpectralBandReplication *sbr, GetBitContext *gb,
790  SBRData *ch_data)
791 {
792  get_bits1_vector(gb, ch_data->bs_df_env, ch_data->bs_num_env);
793  get_bits1_vector(gb, ch_data->bs_df_noise, ch_data->bs_num_noise);
794 }
795 
796 /// Read inverse filtering data
797 static void read_sbr_invf(SpectralBandReplication *sbr, GetBitContext *gb,
798  SBRData *ch_data)
799 {
800  int i;
801 
802  memcpy(ch_data->bs_invf_mode[1], ch_data->bs_invf_mode[0], 5 * sizeof(uint8_t));
803  for (i = 0; i < sbr->n_q; i++)
804  ch_data->bs_invf_mode[0][i] = get_bits(gb, 2);
805 }
806 
807 static void read_sbr_envelope(SpectralBandReplication *sbr, GetBitContext *gb,
808  SBRData *ch_data, int ch)
809 {
810  int bits;
811  int i, j, k;
812  VLC_TYPE (*t_huff)[2], (*f_huff)[2];
813  int t_lav, f_lav;
814  const int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
815  const int odd = sbr->n[1] & 1;
816 
817  if (sbr->bs_coupling && ch) {
818  if (ch_data->bs_amp_res) {
819  bits = 5;
820  t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_3_0DB].table;
821  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_3_0DB];
822  f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
823  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
824  } else {
825  bits = 6;
826  t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_1_5DB].table;
827  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_1_5DB];
828  f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_1_5DB].table;
829  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_1_5DB];
830  }
831  } else {
832  if (ch_data->bs_amp_res) {
833  bits = 6;
834  t_huff = vlc_sbr[T_HUFFMAN_ENV_3_0DB].table;
835  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_3_0DB];
836  f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
837  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
838  } else {
839  bits = 7;
840  t_huff = vlc_sbr[T_HUFFMAN_ENV_1_5DB].table;
841  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_1_5DB];
842  f_huff = vlc_sbr[F_HUFFMAN_ENV_1_5DB].table;
843  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_1_5DB];
844  }
845  }
846 
847  for (i = 0; i < ch_data->bs_num_env; i++) {
848  if (ch_data->bs_df_env[i]) {
849  // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
850  if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
851  for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
852  ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
853  } else if (ch_data->bs_freq_res[i + 1]) {
854  for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
855  k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
856  ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
857  }
858  } else {
859  for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
860  k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
861  ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
862  }
863  }
864  } else {
865  ch_data->env_facs[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
866  for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
867  ch_data->env_facs[i + 1][j] = ch_data->env_facs[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
868  }
869  }
870 
871  //assign 0th elements of env_facs from last elements
872  memcpy(ch_data->env_facs[0], ch_data->env_facs[ch_data->bs_num_env],
873  sizeof(ch_data->env_facs[0]));
874 }
875 
876 static void read_sbr_noise(SpectralBandReplication *sbr, GetBitContext *gb,
877  SBRData *ch_data, int ch)
878 {
879  int i, j;
880  VLC_TYPE (*t_huff)[2], (*f_huff)[2];
881  int t_lav, f_lav;
882  int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
883 
884  if (sbr->bs_coupling && ch) {
885  t_huff = vlc_sbr[T_HUFFMAN_NOISE_BAL_3_0DB].table;
886  t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_BAL_3_0DB];
887  f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
888  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
889  } else {
890  t_huff = vlc_sbr[T_HUFFMAN_NOISE_3_0DB].table;
891  t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_3_0DB];
892  f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
893  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
894  }
895 
896  for (i = 0; i < ch_data->bs_num_noise; i++) {
897  if (ch_data->bs_df_noise[i]) {
898  for (j = 0; j < sbr->n_q; j++)
899  ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 2) - t_lav);
900  } else {
901  ch_data->noise_facs[i + 1][0] = delta * get_bits(gb, 5); // bs_noise_start_value_balance or bs_noise_start_value_level
902  for (j = 1; j < sbr->n_q; j++)
903  ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
904  }
905  }
906 
907  //assign 0th elements of noise_facs from last elements
908  memcpy(ch_data->noise_facs[0], ch_data->noise_facs[ch_data->bs_num_noise],
909  sizeof(ch_data->noise_facs[0]));
910 }
911 
912 static void read_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
913  GetBitContext *gb,
914  int bs_extension_id, int *num_bits_left)
915 {
916  switch (bs_extension_id) {
917  case EXTENSION_ID_PS:
918  if (!ac->oc[1].m4ac.ps) {
919  av_log(ac->avctx, AV_LOG_ERROR, "Parametric Stereo signaled to be not-present but was found in the bitstream.\n");
920  skip_bits_long(gb, *num_bits_left); // bs_fill_bits
921  *num_bits_left = 0;
922  } else {
923 #if 1
924  *num_bits_left -= ff_ps_read_data(ac->avctx, gb, &sbr->ps, *num_bits_left);
925 #else
926  av_log_missing_feature(ac->avctx, "Parametric Stereo", 0);
927  skip_bits_long(gb, *num_bits_left); // bs_fill_bits
928  *num_bits_left = 0;
929 #endif
930  }
931  break;
932  default:
933  // some files contain 0-padding
934  if (bs_extension_id || *num_bits_left > 16 || show_bits(gb, *num_bits_left))
935  av_log_missing_feature(ac->avctx, "Reserved SBR extensions", 1);
936  skip_bits_long(gb, *num_bits_left); // bs_fill_bits
937  *num_bits_left = 0;
938  break;
939  }
940 }
941 
942 static int read_sbr_single_channel_element(AACContext *ac,
943  SpectralBandReplication *sbr,
944  GetBitContext *gb)
945 {
946  if (get_bits1(gb)) // bs_data_extra
947  skip_bits(gb, 4); // bs_reserved
948 
949  if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
950  return -1;
951  read_sbr_dtdf(sbr, gb, &sbr->data[0]);
952  read_sbr_invf(sbr, gb, &sbr->data[0]);
953  read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
954  read_sbr_noise(sbr, gb, &sbr->data[0], 0);
955 
956  if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
957  get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
958 
959  return 0;
960 }
961 
962 static int read_sbr_channel_pair_element(AACContext *ac,
963  SpectralBandReplication *sbr,
964  GetBitContext *gb)
965 {
966  if (get_bits1(gb)) // bs_data_extra
967  skip_bits(gb, 8); // bs_reserved
968 
969  if ((sbr->bs_coupling = get_bits1(gb))) {
970  if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
971  return -1;
972  copy_sbr_grid(&sbr->data[1], &sbr->data[0]);
973  read_sbr_dtdf(sbr, gb, &sbr->data[0]);
974  read_sbr_dtdf(sbr, gb, &sbr->data[1]);
975  read_sbr_invf(sbr, gb, &sbr->data[0]);
976  memcpy(sbr->data[1].bs_invf_mode[1], sbr->data[1].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
977  memcpy(sbr->data[1].bs_invf_mode[0], sbr->data[0].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
978  read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
979  read_sbr_noise(sbr, gb, &sbr->data[0], 0);
980  read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
981  read_sbr_noise(sbr, gb, &sbr->data[1], 1);
982  } else {
983  if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]) ||
984  read_sbr_grid(ac, sbr, gb, &sbr->data[1]))
985  return -1;
986  read_sbr_dtdf(sbr, gb, &sbr->data[0]);
987  read_sbr_dtdf(sbr, gb, &sbr->data[1]);
988  read_sbr_invf(sbr, gb, &sbr->data[0]);
989  read_sbr_invf(sbr, gb, &sbr->data[1]);
990  read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
991  read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
992  read_sbr_noise(sbr, gb, &sbr->data[0], 0);
993  read_sbr_noise(sbr, gb, &sbr->data[1], 1);
994  }
995 
996  if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
997  get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
998  if ((sbr->data[1].bs_add_harmonic_flag = get_bits1(gb)))
999  get_bits1_vector(gb, sbr->data[1].bs_add_harmonic, sbr->n[1]);
1000 
1001  return 0;
1002 }
1003 
1004 static unsigned int read_sbr_data(AACContext *ac, SpectralBandReplication *sbr,
1005  GetBitContext *gb, int id_aac)
1006 {
1007  unsigned int cnt = get_bits_count(gb);
1008 
1009  if (id_aac == TYPE_SCE || id_aac == TYPE_CCE) {
1010  if (read_sbr_single_channel_element(ac, sbr, gb)) {
1011  sbr_turnoff(sbr);
1012  return get_bits_count(gb) - cnt;
1013  }
1014  } else if (id_aac == TYPE_CPE) {
1015  if (read_sbr_channel_pair_element(ac, sbr, gb)) {
1016  sbr_turnoff(sbr);
1017  return get_bits_count(gb) - cnt;
1018  }
1019  } else {
1020  av_log(ac->avctx, AV_LOG_ERROR,
1021  "Invalid bitstream - cannot apply SBR to element type %d\n", id_aac);
1022  sbr_turnoff(sbr);
1023  return get_bits_count(gb) - cnt;
1024  }
1025  if (get_bits1(gb)) { // bs_extended_data
1026  int num_bits_left = get_bits(gb, 4); // bs_extension_size
1027  if (num_bits_left == 15)
1028  num_bits_left += get_bits(gb, 8); // bs_esc_count
1029 
1030  num_bits_left <<= 3;
1031  while (num_bits_left > 7) {
1032  num_bits_left -= 2;
1033  read_sbr_extension(ac, sbr, gb, get_bits(gb, 2), &num_bits_left); // bs_extension_id
1034  }
1035  if (num_bits_left < 0) {
1036  av_log(ac->avctx, AV_LOG_ERROR, "SBR Extension over read.\n");
1037  }
1038  if (num_bits_left > 0)
1039  skip_bits(gb, num_bits_left);
1040  }
1041 
1042  return get_bits_count(gb) - cnt;
1043 }
1044 
1045 static void sbr_reset(AACContext *ac, SpectralBandReplication *sbr)
1046 {
1047  int err;
1048  err = sbr_make_f_master(ac, sbr, &sbr->spectrum_params);
1049  if (err >= 0)
1050  err = sbr_make_f_derived(ac, sbr);
1051  if (err < 0) {
1052  av_log(ac->avctx, AV_LOG_ERROR,
1053  "SBR reset failed. Switching SBR to pure upsampling mode.\n");
1054  sbr_turnoff(sbr);
1055  }
1056 }
1057 
1058 /**
1059  * Decode Spectral Band Replication extension data; reference: table 4.55.
1060  *
1061  * @param crc flag indicating the presence of CRC checksum
1062  * @param cnt length of TYPE_FIL syntactic element in bytes
1063  *
1064  * @return Returns number of bytes consumed from the TYPE_FIL element.
1065  */
1066 int ff_decode_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
1067  GetBitContext *gb_host, int crc, int cnt, int id_aac)
1068 {
1069  unsigned int num_sbr_bits = 0, num_align_bits;
1070  unsigned bytes_read;
1071  GetBitContext gbc = *gb_host, *gb = &gbc;
1072  skip_bits_long(gb_host, cnt*8 - 4);
1073 
1074  sbr->reset = 0;
1075 
1076  if (!sbr->sample_rate)
1077  sbr->sample_rate = 2 * ac->oc[1].m4ac.sample_rate; //TODO use the nominal sample rate for arbitrary sample rate support
1078  if (!ac->oc[1].m4ac.ext_sample_rate)
1079  ac->oc[1].m4ac.ext_sample_rate = 2 * ac->oc[1].m4ac.sample_rate;
1080 
1081  if (crc) {
1082  skip_bits(gb, 10); // bs_sbr_crc_bits; TODO - implement CRC check
1083  num_sbr_bits += 10;
1084  }
1085 
1086  //Save some state from the previous frame.
1087  sbr->kx[0] = sbr->kx[1];
1088  sbr->m[0] = sbr->m[1];
1089  sbr->kx_and_m_pushed = 1;
1090 
1091  num_sbr_bits++;
1092  if (get_bits1(gb)) // bs_header_flag
1093  num_sbr_bits += read_sbr_header(sbr, gb);
1094 
1095  if (sbr->reset)
1096  sbr_reset(ac, sbr);
1097 
1098  if (sbr->start)
1099  num_sbr_bits += read_sbr_data(ac, sbr, gb, id_aac);
1100 
1101  num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
1102  bytes_read = ((num_sbr_bits + num_align_bits + 4) >> 3);
1103 
1104  if (bytes_read > cnt) {
1105  av_log(ac->avctx, AV_LOG_ERROR,
1106  "Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
1107  }
1108  return cnt;
1109 }
1110 
1111 /// Dequantization and stereo decoding (14496-3 sp04 p203)
1112 static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
1113 {
1114  int k, e;
1115  int ch;
1116 
1117  if (id_aac == TYPE_CPE && sbr->bs_coupling) {
1118  float alpha = sbr->data[0].bs_amp_res ? 1.0f : 0.5f;
1119  float pan_offset = sbr->data[0].bs_amp_res ? 12.0f : 24.0f;
1120  for (e = 1; e <= sbr->data[0].bs_num_env; e++) {
1121  for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
1122  float temp1 = exp2f(sbr->data[0].env_facs[e][k] * alpha + 7.0f);
1123  float temp2 = exp2f((pan_offset - sbr->data[1].env_facs[e][k]) * alpha);
1124  float fac;
1125  if (temp1 > 1E20) {
1126  av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
1127  temp1 = 1;
1128  }
1129  fac = temp1 / (1.0f + temp2);
1130  sbr->data[0].env_facs[e][k] = fac;
1131  sbr->data[1].env_facs[e][k] = fac * temp2;
1132  }
1133  }
1134  for (e = 1; e <= sbr->data[0].bs_num_noise; e++) {
1135  for (k = 0; k < sbr->n_q; k++) {
1136  float temp1 = exp2f(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs[e][k] + 1);
1137  float temp2 = exp2f(12 - sbr->data[1].noise_facs[e][k]);
1138  float fac;
1139  if (temp1 > 1E20) {
1140  av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
1141  temp1 = 1;
1142  }
1143  fac = temp1 / (1.0f + temp2);
1144  sbr->data[0].noise_facs[e][k] = fac;
1145  sbr->data[1].noise_facs[e][k] = fac * temp2;
1146  }
1147  }
1148  } else { // SCE or one non-coupled CPE
1149  for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) {
1150  float alpha = sbr->data[ch].bs_amp_res ? 1.0f : 0.5f;
1151  for (e = 1; e <= sbr->data[ch].bs_num_env; e++)
1152  for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++){
1153  sbr->data[ch].env_facs[e][k] =
1154  exp2f(alpha * sbr->data[ch].env_facs[e][k] + 6.0f);
1155  if (sbr->data[ch].env_facs[e][k] > 1E20) {
1156  av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
1157  sbr->data[ch].env_facs[e][k] = 1;
1158  }
1159  }
1160 
1161  for (e = 1; e <= sbr->data[ch].bs_num_noise; e++)
1162  for (k = 0; k < sbr->n_q; k++)
1163  sbr->data[ch].noise_facs[e][k] =
1164  exp2f(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs[e][k]);
1165  }
1166  }
1167 }
1168 
1169 /**
1170  * Analysis QMF Bank (14496-3 sp04 p206)
1171  *
1172  * @param x pointer to the beginning of the first sample window
1173  * @param W array of complex-valued samples split into subbands
1174  */
1175 static void sbr_qmf_analysis(DSPContext *dsp, FFTContext *mdct,
1176  SBRDSPContext *sbrdsp, const float *in, float *x,
1177  float z[320], float W[2][32][32][2], int buf_idx)
1178 {
1179  int i;
1180  memcpy(x , x+1024, (320-32)*sizeof(x[0]));
1181  memcpy(x+288, in, 1024*sizeof(x[0]));
1182  for (i = 0; i < 32; i++) { // numTimeSlots*RATE = 16*2 as 960 sample frames
1183  // are not supported
1184  dsp->vector_fmul_reverse(z, sbr_qmf_window_ds, x, 320);
1185  sbrdsp->sum64x5(z);
1186  sbrdsp->qmf_pre_shuffle(z);
1187  mdct->imdct_half(mdct, z, z+64);
1188  sbrdsp->qmf_post_shuffle(W[buf_idx][i], z);
1189  x += 32;
1190  }
1191 }
1192 
1193 /**
1194  * Synthesis QMF Bank (14496-3 sp04 p206) and Downsampled Synthesis QMF Bank
1195  * (14496-3 sp04 p206)
1196  */
1197 static void sbr_qmf_synthesis(DSPContext *dsp, FFTContext *mdct,
1198  SBRDSPContext *sbrdsp, AVFloatDSPContext *fdsp,
1199  float *out, float X[2][38][64],
1200  float mdct_buf[2][64],
1201  float *v0, int *v_off, const unsigned int div)
1202 {
1203  int i, n;
1204  const float *sbr_qmf_window = div ? sbr_qmf_window_ds : sbr_qmf_window_us;
1205  const int step = 128 >> div;
1206  float *v;
1207  for (i = 0; i < 32; i++) {
1208  if (*v_off < step) {
1209  int saved_samples = (1280 - 128) >> div;
1210  memcpy(&v0[SBR_SYNTHESIS_BUF_SIZE - saved_samples], v0, saved_samples * sizeof(float));
1211  *v_off = SBR_SYNTHESIS_BUF_SIZE - saved_samples - step;
1212  } else {
1213  *v_off -= step;
1214  }
1215  v = v0 + *v_off;
1216  if (div) {
1217  for (n = 0; n < 32; n++) {
1218  X[0][i][ n] = -X[0][i][n];
1219  X[0][i][32+n] = X[1][i][31-n];
1220  }
1221  mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1222  sbrdsp->qmf_deint_neg(v, mdct_buf[0]);
1223  } else {
1224  sbrdsp->neg_odd_64(X[1][i]);
1225  mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1226  mdct->imdct_half(mdct, mdct_buf[1], X[1][i]);
1227  sbrdsp->qmf_deint_bfly(v, mdct_buf[1], mdct_buf[0]);
1228  }
1229  fdsp->vector_fmul (out, v , sbr_qmf_window , 64 >> div);
1230  dsp->vector_fmul_add(out, v + ( 192 >> div), sbr_qmf_window + ( 64 >> div), out , 64 >> div);
1231  dsp->vector_fmul_add(out, v + ( 256 >> div), sbr_qmf_window + (128 >> div), out , 64 >> div);
1232  dsp->vector_fmul_add(out, v + ( 448 >> div), sbr_qmf_window + (192 >> div), out , 64 >> div);
1233  dsp->vector_fmul_add(out, v + ( 512 >> div), sbr_qmf_window + (256 >> div), out , 64 >> div);
1234  dsp->vector_fmul_add(out, v + ( 704 >> div), sbr_qmf_window + (320 >> div), out , 64 >> div);
1235  dsp->vector_fmul_add(out, v + ( 768 >> div), sbr_qmf_window + (384 >> div), out , 64 >> div);
1236  dsp->vector_fmul_add(out, v + ( 960 >> div), sbr_qmf_window + (448 >> div), out , 64 >> div);
1237  dsp->vector_fmul_add(out, v + (1024 >> div), sbr_qmf_window + (512 >> div), out , 64 >> div);
1238  dsp->vector_fmul_add(out, v + (1216 >> div), sbr_qmf_window + (576 >> div), out , 64 >> div);
1239  out += 64 >> div;
1240  }
1241 }
1242 
1243 /** High Frequency Generation (14496-3 sp04 p214+) and Inverse Filtering
1244  * (14496-3 sp04 p214)
1245  * Warning: This routine does not seem numerically stable.
1246  */
1247 static void sbr_hf_inverse_filter(SBRDSPContext *dsp,
1248  float (*alpha0)[2], float (*alpha1)[2],
1249  const float X_low[32][40][2], int k0)
1250 {
1251  int k;
1252  for (k = 0; k < k0; k++) {
1253  LOCAL_ALIGNED_16(float, phi, [3], [2][2]);
1254  float dk;
1255 
1256  dsp->autocorrelate(X_low[k], phi);
1257 
1258  dk = phi[2][1][0] * phi[1][0][0] -
1259  (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f;
1260 
1261  if (!dk) {
1262  alpha1[k][0] = 0;
1263  alpha1[k][1] = 0;
1264  } else {
1265  float temp_real, temp_im;
1266  temp_real = phi[0][0][0] * phi[1][1][0] -
1267  phi[0][0][1] * phi[1][1][1] -
1268  phi[0][1][0] * phi[1][0][0];
1269  temp_im = phi[0][0][0] * phi[1][1][1] +
1270  phi[0][0][1] * phi[1][1][0] -
1271  phi[0][1][1] * phi[1][0][0];
1272 
1273  alpha1[k][0] = temp_real / dk;
1274  alpha1[k][1] = temp_im / dk;
1275  }
1276 
1277  if (!phi[1][0][0]) {
1278  alpha0[k][0] = 0;
1279  alpha0[k][1] = 0;
1280  } else {
1281  float temp_real, temp_im;
1282  temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] +
1283  alpha1[k][1] * phi[1][1][1];
1284  temp_im = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] -
1285  alpha1[k][0] * phi[1][1][1];
1286 
1287  alpha0[k][0] = -temp_real / phi[1][0][0];
1288  alpha0[k][1] = -temp_im / phi[1][0][0];
1289  }
1290 
1291  if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f ||
1292  alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) {
1293  alpha1[k][0] = 0;
1294  alpha1[k][1] = 0;
1295  alpha0[k][0] = 0;
1296  alpha0[k][1] = 0;
1297  }
1298  }
1299 }
1300 
1301 /// Chirp Factors (14496-3 sp04 p214)
1302 static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data)
1303 {
1304  int i;
1305  float new_bw;
1306  static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f };
1307 
1308  for (i = 0; i < sbr->n_q; i++) {
1309  if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) {
1310  new_bw = 0.6f;
1311  } else
1312  new_bw = bw_tab[ch_data->bs_invf_mode[0][i]];
1313 
1314  if (new_bw < ch_data->bw_array[i]) {
1315  new_bw = 0.75f * new_bw + 0.25f * ch_data->bw_array[i];
1316  } else
1317  new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i];
1318  ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw;
1319  }
1320 }
1321 
1322 /// Generate the subband filtered lowband
1323 static int sbr_lf_gen(AACContext *ac, SpectralBandReplication *sbr,
1324  float X_low[32][40][2], const float W[2][32][32][2],
1325  int buf_idx)
1326 {
1327  int i, k;
1328  const int t_HFGen = 8;
1329  const int i_f = 32;
1330  memset(X_low, 0, 32*sizeof(*X_low));
1331  for (k = 0; k < sbr->kx[1]; k++) {
1332  for (i = t_HFGen; i < i_f + t_HFGen; i++) {
1333  X_low[k][i][0] = W[buf_idx][i - t_HFGen][k][0];
1334  X_low[k][i][1] = W[buf_idx][i - t_HFGen][k][1];
1335  }
1336  }
1337  buf_idx = 1-buf_idx;
1338  for (k = 0; k < sbr->kx[0]; k++) {
1339  for (i = 0; i < t_HFGen; i++) {
1340  X_low[k][i][0] = W[buf_idx][i + i_f - t_HFGen][k][0];
1341  X_low[k][i][1] = W[buf_idx][i + i_f - t_HFGen][k][1];
1342  }
1343  }
1344  return 0;
1345 }
1346 
1347 /// High Frequency Generator (14496-3 sp04 p215)
1348 static int sbr_hf_gen(AACContext *ac, SpectralBandReplication *sbr,
1349  float X_high[64][40][2], const float X_low[32][40][2],
1350  const float (*alpha0)[2], const float (*alpha1)[2],
1351  const float bw_array[5], const uint8_t *t_env,
1352  int bs_num_env)
1353 {
1354  int j, x;
1355  int g = 0;
1356  int k = sbr->kx[1];
1357  for (j = 0; j < sbr->num_patches; j++) {
1358  for (x = 0; x < sbr->patch_num_subbands[j]; x++, k++) {
1359  const int p = sbr->patch_start_subband[j] + x;
1360  while (g <= sbr->n_q && k >= sbr->f_tablenoise[g])
1361  g++;
1362  g--;
1363 
1364  if (g < 0) {
1365  av_log(ac->avctx, AV_LOG_ERROR,
1366  "ERROR : no subband found for frequency %d\n", k);
1367  return -1;
1368  }
1369 
1370  sbr->dsp.hf_gen(X_high[k] + ENVELOPE_ADJUSTMENT_OFFSET,
1371  X_low[p] + ENVELOPE_ADJUSTMENT_OFFSET,
1372  alpha0[p], alpha1[p], bw_array[g],
1373  2 * t_env[0], 2 * t_env[bs_num_env]);
1374  }
1375  }
1376  if (k < sbr->m[1] + sbr->kx[1])
1377  memset(X_high + k, 0, (sbr->m[1] + sbr->kx[1] - k) * sizeof(*X_high));
1378 
1379  return 0;
1380 }
1381 
1382 /// Generate the subband filtered lowband
1383 static int sbr_x_gen(SpectralBandReplication *sbr, float X[2][38][64],
1384  const float Y0[38][64][2], const float Y1[38][64][2],
1385  const float X_low[32][40][2], int ch)
1386 {
1387  int k, i;
1388  const int i_f = 32;
1389  const int i_Temp = FFMAX(2*sbr->data[ch].t_env_num_env_old - i_f, 0);
1390  memset(X, 0, 2*sizeof(*X));
1391  for (k = 0; k < sbr->kx[0]; k++) {
1392  for (i = 0; i < i_Temp; i++) {
1393  X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1394  X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1395  }
1396  }
1397  for (; k < sbr->kx[0] + sbr->m[0]; k++) {
1398  for (i = 0; i < i_Temp; i++) {
1399  X[0][i][k] = Y0[i + i_f][k][0];
1400  X[1][i][k] = Y0[i + i_f][k][1];
1401  }
1402  }
1403 
1404  for (k = 0; k < sbr->kx[1]; k++) {
1405  for (i = i_Temp; i < 38; i++) {
1406  X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1407  X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1408  }
1409  }
1410  for (; k < sbr->kx[1] + sbr->m[1]; k++) {
1411  for (i = i_Temp; i < i_f; i++) {
1412  X[0][i][k] = Y1[i][k][0];
1413  X[1][i][k] = Y1[i][k][1];
1414  }
1415  }
1416  return 0;
1417 }
1418 
1419 /** High Frequency Adjustment (14496-3 sp04 p217) and Mapping
1420  * (14496-3 sp04 p217)
1421  */
1422 static int sbr_mapping(AACContext *ac, SpectralBandReplication *sbr,
1423  SBRData *ch_data, int e_a[2])
1424 {
1425  int e, i, m;
1426 
1427  memset(ch_data->s_indexmapped[1], 0, 7*sizeof(ch_data->s_indexmapped[1]));
1428  for (e = 0; e < ch_data->bs_num_env; e++) {
1429  const unsigned int ilim = sbr->n[ch_data->bs_freq_res[e + 1]];
1430  uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1431  int k;
1432 
1433  if (sbr->kx[1] != table[0]) {
1434  av_log(ac->avctx, AV_LOG_ERROR, "kx != f_table{high,low}[0]. "
1435  "Derived frequency tables were not regenerated.\n");
1436  sbr_turnoff(sbr);
1437  return AVERROR_BUG;
1438  }
1439  for (i = 0; i < ilim; i++)
1440  for (m = table[i]; m < table[i + 1]; m++)
1441  sbr->e_origmapped[e][m - sbr->kx[1]] = ch_data->env_facs[e+1][i];
1442 
1443  // ch_data->bs_num_noise > 1 => 2 noise floors
1444  k = (ch_data->bs_num_noise > 1) && (ch_data->t_env[e] >= ch_data->t_q[1]);
1445  for (i = 0; i < sbr->n_q; i++)
1446  for (m = sbr->f_tablenoise[i]; m < sbr->f_tablenoise[i + 1]; m++)
1447  sbr->q_mapped[e][m - sbr->kx[1]] = ch_data->noise_facs[k+1][i];
1448 
1449  for (i = 0; i < sbr->n[1]; i++) {
1450  if (ch_data->bs_add_harmonic_flag) {
1451  const unsigned int m_midpoint =
1452  (sbr->f_tablehigh[i] + sbr->f_tablehigh[i + 1]) >> 1;
1453 
1454  ch_data->s_indexmapped[e + 1][m_midpoint - sbr->kx[1]] = ch_data->bs_add_harmonic[i] *
1455  (e >= e_a[1] || (ch_data->s_indexmapped[0][m_midpoint - sbr->kx[1]] == 1));
1456  }
1457  }
1458 
1459  for (i = 0; i < ilim; i++) {
1460  int additional_sinusoid_present = 0;
1461  for (m = table[i]; m < table[i + 1]; m++) {
1462  if (ch_data->s_indexmapped[e + 1][m - sbr->kx[1]]) {
1463  additional_sinusoid_present = 1;
1464  break;
1465  }
1466  }
1467  memset(&sbr->s_mapped[e][table[i] - sbr->kx[1]], additional_sinusoid_present,
1468  (table[i + 1] - table[i]) * sizeof(sbr->s_mapped[e][0]));
1469  }
1470  }
1471 
1472  memcpy(ch_data->s_indexmapped[0], ch_data->s_indexmapped[ch_data->bs_num_env], sizeof(ch_data->s_indexmapped[0]));
1473  return 0;
1474 }
1475 
1476 /// Estimation of current envelope (14496-3 sp04 p218)
1477 static void sbr_env_estimate(float (*e_curr)[48], float X_high[64][40][2],
1478  SpectralBandReplication *sbr, SBRData *ch_data)
1479 {
1480  int e, m;
1481  int kx1 = sbr->kx[1];
1482 
1483  if (sbr->bs_interpol_freq) {
1484  for (e = 0; e < ch_data->bs_num_env; e++) {
1485  const float recip_env_size = 0.5f / (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1486  int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1487  int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1488 
1489  for (m = 0; m < sbr->m[1]; m++) {
1490  float sum = sbr->dsp.sum_square(X_high[m+kx1] + ilb, iub - ilb);
1491  e_curr[e][m] = sum * recip_env_size;
1492  }
1493  }
1494  } else {
1495  int k, p;
1496 
1497  for (e = 0; e < ch_data->bs_num_env; e++) {
1498  const int env_size = 2 * (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1499  int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1500  int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1501  const uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1502 
1503  for (p = 0; p < sbr->n[ch_data->bs_freq_res[e + 1]]; p++) {
1504  float sum = 0.0f;
1505  const int den = env_size * (table[p + 1] - table[p]);
1506 
1507  for (k = table[p]; k < table[p + 1]; k++) {
1508  sum += sbr->dsp.sum_square(X_high[k] + ilb, iub - ilb);
1509  }
1510  sum /= den;
1511  for (k = table[p]; k < table[p + 1]; k++) {
1512  e_curr[e][k - kx1] = sum;
1513  }
1514  }
1515  }
1516  }
1517 }
1518 
1519 /**
1520  * Calculation of levels of additional HF signal components (14496-3 sp04 p219)
1521  * and Calculation of gain (14496-3 sp04 p219)
1522  */
1523 static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr,
1524  SBRData *ch_data, const int e_a[2])
1525 {
1526  int e, k, m;
1527  // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off)
1528  static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 };
1529 
1530  for (e = 0; e < ch_data->bs_num_env; e++) {
1531  int delta = !((e == e_a[1]) || (e == e_a[0]));
1532  for (k = 0; k < sbr->n_lim; k++) {
1533  float gain_boost, gain_max;
1534  float sum[2] = { 0.0f, 0.0f };
1535  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1536  const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]);
1537  sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]);
1538  sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]);
1539  if (!sbr->s_mapped[e][m]) {
1540  sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] /
1541  ((1.0f + sbr->e_curr[e][m]) *
1542  (1.0f + sbr->q_mapped[e][m] * delta)));
1543  } else {
1544  sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] /
1545  ((1.0f + sbr->e_curr[e][m]) *
1546  (1.0f + sbr->q_mapped[e][m])));
1547  }
1548  }
1549  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1550  sum[0] += sbr->e_origmapped[e][m];
1551  sum[1] += sbr->e_curr[e][m];
1552  }
1553  gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1554  gain_max = FFMIN(100000.f, gain_max);
1555  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1556  float q_m_max = sbr->q_m[e][m] * gain_max / sbr->gain[e][m];
1557  sbr->q_m[e][m] = FFMIN(sbr->q_m[e][m], q_m_max);
1558  sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max);
1559  }
1560  sum[0] = sum[1] = 0.0f;
1561  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1562  sum[0] += sbr->e_origmapped[e][m];
1563  sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m]
1564  + sbr->s_m[e][m] * sbr->s_m[e][m]
1565  + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m];
1566  }
1567  gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1568  gain_boost = FFMIN(1.584893192f, gain_boost);
1569  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1570  sbr->gain[e][m] *= gain_boost;
1571  sbr->q_m[e][m] *= gain_boost;
1572  sbr->s_m[e][m] *= gain_boost;
1573  }
1574  }
1575  }
1576 }
1577 
1578 /// Assembling HF Signals (14496-3 sp04 p220)
1579 static void sbr_hf_assemble(float Y1[38][64][2],
1580  const float X_high[64][40][2],
1581  SpectralBandReplication *sbr, SBRData *ch_data,
1582  const int e_a[2])
1583 {
1584  int e, i, j, m;
1585  const int h_SL = 4 * !sbr->bs_smoothing_mode;
1586  const int kx = sbr->kx[1];
1587  const int m_max = sbr->m[1];
1588  static const float h_smooth[5] = {
1589  0.33333333333333,
1590  0.30150283239582,
1591  0.21816949906249,
1592  0.11516383427084,
1593  0.03183050093751,
1594  };
1595  float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp;
1596  int indexnoise = ch_data->f_indexnoise;
1597  int indexsine = ch_data->f_indexsine;
1598 
1599  if (sbr->reset) {
1600  for (i = 0; i < h_SL; i++) {
1601  memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0]));
1602  memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0], m_max * sizeof(sbr->q_m[0][0]));
1603  }
1604  } else if (h_SL) {
1605  memcpy(g_temp[2*ch_data->t_env[0]], g_temp[2*ch_data->t_env_num_env_old], 4*sizeof(g_temp[0]));
1606  memcpy(q_temp[2*ch_data->t_env[0]], q_temp[2*ch_data->t_env_num_env_old], 4*sizeof(q_temp[0]));
1607  }
1608 
1609  for (e = 0; e < ch_data->bs_num_env; e++) {
1610  for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1611  memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0]));
1612  memcpy(q_temp[h_SL + i], sbr->q_m[e], m_max * sizeof(sbr->q_m[0][0]));
1613  }
1614  }
1615 
1616  for (e = 0; e < ch_data->bs_num_env; e++) {
1617  for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1618  LOCAL_ALIGNED_16(float, g_filt_tab, [48]);
1619  LOCAL_ALIGNED_16(float, q_filt_tab, [48]);
1620  float *g_filt, *q_filt;
1621 
1622  if (h_SL && e != e_a[0] && e != e_a[1]) {
1623  g_filt = g_filt_tab;
1624  q_filt = q_filt_tab;
1625  for (m = 0; m < m_max; m++) {
1626  const int idx1 = i + h_SL;
1627  g_filt[m] = 0.0f;
1628  q_filt[m] = 0.0f;
1629  for (j = 0; j <= h_SL; j++) {
1630  g_filt[m] += g_temp[idx1 - j][m] * h_smooth[j];
1631  q_filt[m] += q_temp[idx1 - j][m] * h_smooth[j];
1632  }
1633  }
1634  } else {
1635  g_filt = g_temp[i + h_SL];
1636  q_filt = q_temp[i];
1637  }
1638 
1639  sbr->dsp.hf_g_filt(Y1[i] + kx, X_high + kx, g_filt, m_max,
1640  i + ENVELOPE_ADJUSTMENT_OFFSET);
1641 
1642  if (e != e_a[0] && e != e_a[1]) {
1643  sbr->dsp.hf_apply_noise[indexsine](Y1[i] + kx, sbr->s_m[e],
1644  q_filt, indexnoise,
1645  kx, m_max);
1646  } else {
1647  int idx = indexsine&1;
1648  int A = (1-((indexsine+(kx & 1))&2));
1649  int B = (A^(-idx)) + idx;
1650  float *out = &Y1[i][kx][idx];
1651  float *in = sbr->s_m[e];
1652  for (m = 0; m+1 < m_max; m+=2) {
1653  out[2*m ] += in[m ] * A;
1654  out[2*m+2] += in[m+1] * B;
1655  }
1656  if(m_max&1)
1657  out[2*m ] += in[m ] * A;
1658  }
1659  indexnoise = (indexnoise + m_max) & 0x1ff;
1660  indexsine = (indexsine + 1) & 3;
1661  }
1662  }
1663  ch_data->f_indexnoise = indexnoise;
1664  ch_data->f_indexsine = indexsine;
1665 }
1666 
1667 void ff_sbr_apply(AACContext *ac, SpectralBandReplication *sbr, int id_aac,
1668  float* L, float* R)
1669 {
1670  int downsampled = ac->oc[1].m4ac.ext_sample_rate < sbr->sample_rate;
1671  int ch;
1672  int nch = (id_aac == TYPE_CPE) ? 2 : 1;
1673  int err;
1674 
1675  if (!sbr->kx_and_m_pushed) {
1676  sbr->kx[0] = sbr->kx[1];
1677  sbr->m[0] = sbr->m[1];
1678  } else {
1679  sbr->kx_and_m_pushed = 0;
1680  }
1681 
1682  if (sbr->start) {
1683  sbr_dequant(sbr, id_aac);
1684  }
1685  for (ch = 0; ch < nch; ch++) {
1686  /* decode channel */
1687  sbr_qmf_analysis(&ac->dsp, &sbr->mdct_ana, &sbr->dsp, ch ? R : L, sbr->data[ch].analysis_filterbank_samples,
1688  (float*)sbr->qmf_filter_scratch,
1689  sbr->data[ch].W, sbr->data[ch].Ypos);
1690  sbr_lf_gen(ac, sbr, sbr->X_low, sbr->data[ch].W, sbr->data[ch].Ypos);
1691  sbr->data[ch].Ypos ^= 1;
1692  if (sbr->start) {
1693  sbr_hf_inverse_filter(&sbr->dsp, sbr->alpha0, sbr->alpha1, sbr->X_low, sbr->k[0]);
1694  sbr_chirp(sbr, &sbr->data[ch]);
1695  sbr_hf_gen(ac, sbr, sbr->X_high, sbr->X_low, sbr->alpha0, sbr->alpha1,
1696  sbr->data[ch].bw_array, sbr->data[ch].t_env,
1697  sbr->data[ch].bs_num_env);
1698 
1699  // hf_adj
1700  err = sbr_mapping(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1701  if (!err) {
1702  sbr_env_estimate(sbr->e_curr, sbr->X_high, sbr, &sbr->data[ch]);
1703  sbr_gain_calc(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1704  sbr_hf_assemble(sbr->data[ch].Y[sbr->data[ch].Ypos],
1705  sbr->X_high, sbr, &sbr->data[ch],
1706  sbr->data[ch].e_a);
1707  }
1708  }
1709 
1710  /* synthesis */
1711  sbr_x_gen(sbr, sbr->X[ch],
1712  sbr->data[ch].Y[1-sbr->data[ch].Ypos],
1713  sbr->data[ch].Y[ sbr->data[ch].Ypos],
1714  sbr->X_low, ch);
1715  }
1716 
1717  if (ac->oc[1].m4ac.ps == 1) {
1718  if (sbr->ps.start) {
1719  ff_ps_apply(ac->avctx, &sbr->ps, sbr->X[0], sbr->X[1], sbr->kx[1] + sbr->m[1]);
1720  } else {
1721  memcpy(sbr->X[1], sbr->X[0], sizeof(sbr->X[0]));
1722  }
1723  nch = 2;
1724  }
1725 
1726  sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, &sbr->dsp, &ac->fdsp,
1727  L, sbr->X[0], sbr->qmf_filter_scratch,
1728  sbr->data[0].synthesis_filterbank_samples,
1729  &sbr->data[0].synthesis_filterbank_samples_offset,
1730  downsampled);
1731  if (nch == 2)
1732  sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, &sbr->dsp, &ac->fdsp,
1733  R, sbr->X[1], sbr->qmf_filter_scratch,
1734  sbr->data[1].synthesis_filterbank_samples,
1735  &sbr->data[1].synthesis_filterbank_samples_offset,
1736  downsampled);
1737 }
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