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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/internal.h"
37 #include "libavutil/libm.h"
38 #include "libavutil/avassert.h"
39 
40 #include <stdint.h>
41 #include <float.h>
42 #include <math.h>
43 
44 #define ENVELOPE_ADJUSTMENT_OFFSET 2
45 #define NOISE_FLOOR_OFFSET 6.0f
46 
47 #if ARCH_MIPS
48 #include "mips/aacsbr_mips.h"
49 #endif /* ARCH_MIPS */
50 
51 /**
52  * SBR VLC tables
53  */
54 enum {
55  T_HUFFMAN_ENV_1_5DB,
56  F_HUFFMAN_ENV_1_5DB,
57  T_HUFFMAN_ENV_BAL_1_5DB,
58  F_HUFFMAN_ENV_BAL_1_5DB,
59  T_HUFFMAN_ENV_3_0DB,
60  F_HUFFMAN_ENV_3_0DB,
61  T_HUFFMAN_ENV_BAL_3_0DB,
62  F_HUFFMAN_ENV_BAL_3_0DB,
63  T_HUFFMAN_NOISE_3_0DB,
64  T_HUFFMAN_NOISE_BAL_3_0DB,
65 };
66 
67 /**
68  * bs_frame_class - frame class of current SBR frame (14496-3 sp04 p98)
69  */
70 enum {
71  FIXFIX,
72  FIXVAR,
73  VARFIX,
74  VARVAR,
75 };
76 
77 enum {
78  EXTENSION_ID_PS = 2,
79 };
80 
81 static VLC vlc_sbr[10];
82 static const int8_t vlc_sbr_lav[10] =
83  { 60, 60, 24, 24, 31, 31, 12, 12, 31, 12 };
84 
85 #define SBR_INIT_VLC_STATIC(num, size) \
86  INIT_VLC_STATIC(&vlc_sbr[num], 9, sbr_tmp[num].table_size / sbr_tmp[num].elem_size, \
87  sbr_tmp[num].sbr_bits , 1, 1, \
88  sbr_tmp[num].sbr_codes, sbr_tmp[num].elem_size, sbr_tmp[num].elem_size, \
89  size)
90 
91 #define SBR_VLC_ROW(name) \
92  { name ## _codes, name ## _bits, sizeof(name ## _codes), sizeof(name ## _codes[0]) }
93 
94 static void aacsbr_func_ptr_init(AACSBRContext *c);
95 
96 av_cold void ff_aac_sbr_init(void)
97 {
98  int n;
99  static const struct {
100  const void *sbr_codes, *sbr_bits;
101  const unsigned int table_size, elem_size;
102  } sbr_tmp[] = {
103  SBR_VLC_ROW(t_huffman_env_1_5dB),
104  SBR_VLC_ROW(f_huffman_env_1_5dB),
105  SBR_VLC_ROW(t_huffman_env_bal_1_5dB),
106  SBR_VLC_ROW(f_huffman_env_bal_1_5dB),
107  SBR_VLC_ROW(t_huffman_env_3_0dB),
108  SBR_VLC_ROW(f_huffman_env_3_0dB),
109  SBR_VLC_ROW(t_huffman_env_bal_3_0dB),
110  SBR_VLC_ROW(f_huffman_env_bal_3_0dB),
111  SBR_VLC_ROW(t_huffman_noise_3_0dB),
112  SBR_VLC_ROW(t_huffman_noise_bal_3_0dB),
113  };
114 
115  // SBR VLC table initialization
116  SBR_INIT_VLC_STATIC(0, 1098);
117  SBR_INIT_VLC_STATIC(1, 1092);
118  SBR_INIT_VLC_STATIC(2, 768);
119  SBR_INIT_VLC_STATIC(3, 1026);
120  SBR_INIT_VLC_STATIC(4, 1058);
121  SBR_INIT_VLC_STATIC(5, 1052);
122  SBR_INIT_VLC_STATIC(6, 544);
123  SBR_INIT_VLC_STATIC(7, 544);
124  SBR_INIT_VLC_STATIC(8, 592);
125  SBR_INIT_VLC_STATIC(9, 512);
126 
127  for (n = 1; n < 320; n++)
128  sbr_qmf_window_us[320 + n] = sbr_qmf_window_us[320 - n];
129  sbr_qmf_window_us[384] = -sbr_qmf_window_us[384];
130  sbr_qmf_window_us[512] = -sbr_qmf_window_us[512];
131 
132  for (n = 0; n < 320; n++)
133  sbr_qmf_window_ds[n] = sbr_qmf_window_us[2*n];
134 
135  ff_ps_init();
136 }
137 
138 /** Places SBR in pure upsampling mode. */
139 static void sbr_turnoff(SpectralBandReplication *sbr) {
140  sbr->start = 0;
141  // Init defults used in pure upsampling mode
142  sbr->kx[1] = 32; //Typo in spec, kx' inits to 32
143  sbr->m[1] = 0;
144  // Reset values for first SBR header
145  sbr->data[0].e_a[1] = sbr->data[1].e_a[1] = -1;
146  memset(&sbr->spectrum_params, -1, sizeof(SpectrumParameters));
147 }
148 
149 av_cold void ff_aac_sbr_ctx_init(AACContext *ac, SpectralBandReplication *sbr)
150 {
151  if(sbr->mdct.mdct_bits)
152  return;
153  sbr->kx[0] = sbr->kx[1];
154  sbr_turnoff(sbr);
155  sbr->data[0].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
156  sbr->data[1].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
157  /* SBR requires samples to be scaled to +/-32768.0 to work correctly.
158  * mdct scale factors are adjusted to scale up from +/-1.0 at analysis
159  * and scale back down at synthesis. */
160  ff_mdct_init(&sbr->mdct, 7, 1, 1.0 / (64 * 32768.0));
161  ff_mdct_init(&sbr->mdct_ana, 7, 1, -2.0 * 32768.0);
162  ff_ps_ctx_init(&sbr->ps);
163  ff_sbrdsp_init(&sbr->dsp);
164  aacsbr_func_ptr_init(&sbr->c);
165 }
166 
167 av_cold void ff_aac_sbr_ctx_close(SpectralBandReplication *sbr)
168 {
169  ff_mdct_end(&sbr->mdct);
170  ff_mdct_end(&sbr->mdct_ana);
171 }
172 
173 static int qsort_comparison_function_int16(const void *a, const void *b)
174 {
175  return *(const int16_t *)a - *(const int16_t *)b;
176 }
177 
178 static inline int in_table_int16(const int16_t *table, int last_el, int16_t needle)
179 {
180  int i;
181  for (i = 0; i <= last_el; i++)
182  if (table[i] == needle)
183  return 1;
184  return 0;
185 }
186 
187 /// Limiter Frequency Band Table (14496-3 sp04 p198)
188 static void sbr_make_f_tablelim(SpectralBandReplication *sbr)
189 {
190  int k;
191  if (sbr->bs_limiter_bands > 0) {
192  static const float bands_warped[3] = { 1.32715174233856803909f, //2^(0.49/1.2)
193  1.18509277094158210129f, //2^(0.49/2)
194  1.11987160404675912501f }; //2^(0.49/3)
195  const float lim_bands_per_octave_warped = bands_warped[sbr->bs_limiter_bands - 1];
196  int16_t patch_borders[7];
197  uint16_t *in = sbr->f_tablelim + 1, *out = sbr->f_tablelim;
198 
199  patch_borders[0] = sbr->kx[1];
200  for (k = 1; k <= sbr->num_patches; k++)
201  patch_borders[k] = patch_borders[k-1] + sbr->patch_num_subbands[k-1];
202 
203  memcpy(sbr->f_tablelim, sbr->f_tablelow,
204  (sbr->n[0] + 1) * sizeof(sbr->f_tablelow[0]));
205  if (sbr->num_patches > 1)
206  memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
207  (sbr->num_patches - 1) * sizeof(patch_borders[0]));
208 
209  qsort(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
210  sizeof(sbr->f_tablelim[0]),
211  qsort_comparison_function_int16);
212 
213  sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
214  while (out < sbr->f_tablelim + sbr->n_lim) {
215  if (*in >= *out * lim_bands_per_octave_warped) {
216  *++out = *in++;
217  } else if (*in == *out ||
218  !in_table_int16(patch_borders, sbr->num_patches, *in)) {
219  in++;
220  sbr->n_lim--;
221  } else if (!in_table_int16(patch_borders, sbr->num_patches, *out)) {
222  *out = *in++;
223  sbr->n_lim--;
224  } else {
225  *++out = *in++;
226  }
227  }
228  } else {
229  sbr->f_tablelim[0] = sbr->f_tablelow[0];
230  sbr->f_tablelim[1] = sbr->f_tablelow[sbr->n[0]];
231  sbr->n_lim = 1;
232  }
233 }
234 
235 static unsigned int read_sbr_header(SpectralBandReplication *sbr, GetBitContext *gb)
236 {
237  unsigned int cnt = get_bits_count(gb);
238  uint8_t bs_header_extra_1;
239  uint8_t bs_header_extra_2;
240  int old_bs_limiter_bands = sbr->bs_limiter_bands;
241  SpectrumParameters old_spectrum_params;
242 
243  sbr->start = 1;
244 
245  // Save last spectrum parameters variables to compare to new ones
246  memcpy(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters));
247 
248  sbr->bs_amp_res_header = get_bits1(gb);
249  sbr->spectrum_params.bs_start_freq = get_bits(gb, 4);
250  sbr->spectrum_params.bs_stop_freq = get_bits(gb, 4);
251  sbr->spectrum_params.bs_xover_band = get_bits(gb, 3);
252  skip_bits(gb, 2); // bs_reserved
253 
254  bs_header_extra_1 = get_bits1(gb);
255  bs_header_extra_2 = get_bits1(gb);
256 
257  if (bs_header_extra_1) {
258  sbr->spectrum_params.bs_freq_scale = get_bits(gb, 2);
259  sbr->spectrum_params.bs_alter_scale = get_bits1(gb);
260  sbr->spectrum_params.bs_noise_bands = get_bits(gb, 2);
261  } else {
262  sbr->spectrum_params.bs_freq_scale = 2;
263  sbr->spectrum_params.bs_alter_scale = 1;
264  sbr->spectrum_params.bs_noise_bands = 2;
265  }
266 
267  // Check if spectrum parameters changed
268  if (memcmp(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters)))
269  sbr->reset = 1;
270 
271  if (bs_header_extra_2) {
272  sbr->bs_limiter_bands = get_bits(gb, 2);
273  sbr->bs_limiter_gains = get_bits(gb, 2);
274  sbr->bs_interpol_freq = get_bits1(gb);
275  sbr->bs_smoothing_mode = get_bits1(gb);
276  } else {
277  sbr->bs_limiter_bands = 2;
278  sbr->bs_limiter_gains = 2;
279  sbr->bs_interpol_freq = 1;
280  sbr->bs_smoothing_mode = 1;
281  }
282 
283  if (sbr->bs_limiter_bands != old_bs_limiter_bands && !sbr->reset)
284  sbr_make_f_tablelim(sbr);
285 
286  return get_bits_count(gb) - cnt;
287 }
288 
289 static int array_min_int16(const int16_t *array, int nel)
290 {
291  int i, min = array[0];
292  for (i = 1; i < nel; i++)
293  min = FFMIN(array[i], min);
294  return min;
295 }
296 
297 static void make_bands(int16_t* bands, int start, int stop, int num_bands)
298 {
299  int k, previous, present;
300  float base, prod;
301 
302  base = powf((float)stop / start, 1.0f / num_bands);
303  prod = start;
304  previous = start;
305 
306  for (k = 0; k < num_bands-1; k++) {
307  prod *= base;
308  present = lrintf(prod);
309  bands[k] = present - previous;
310  previous = present;
311  }
312  bands[num_bands-1] = stop - previous;
313 }
314 
315 static int check_n_master(AVCodecContext *avctx, int n_master, int bs_xover_band)
316 {
317  // Requirements (14496-3 sp04 p205)
318  if (n_master <= 0) {
319  av_log(avctx, AV_LOG_ERROR, "Invalid n_master: %d\n", n_master);
320  return -1;
321  }
322  if (bs_xover_band >= n_master) {
323  av_log(avctx, AV_LOG_ERROR,
324  "Invalid bitstream, crossover band index beyond array bounds: %d\n",
325  bs_xover_band);
326  return -1;
327  }
328  return 0;
329 }
330 
331 /// Master Frequency Band Table (14496-3 sp04 p194)
332 static int sbr_make_f_master(AACContext *ac, SpectralBandReplication *sbr,
333  SpectrumParameters *spectrum)
334 {
335  unsigned int temp, max_qmf_subbands;
336  unsigned int start_min, stop_min;
337  int k;
338  const int8_t *sbr_offset_ptr;
339  int16_t stop_dk[13];
340 
341  if (sbr->sample_rate < 32000) {
342  temp = 3000;
343  } else if (sbr->sample_rate < 64000) {
344  temp = 4000;
345  } else
346  temp = 5000;
347 
348  switch (sbr->sample_rate) {
349  case 16000:
350  sbr_offset_ptr = sbr_offset[0];
351  break;
352  case 22050:
353  sbr_offset_ptr = sbr_offset[1];
354  break;
355  case 24000:
356  sbr_offset_ptr = sbr_offset[2];
357  break;
358  case 32000:
359  sbr_offset_ptr = sbr_offset[3];
360  break;
361  case 44100: case 48000: case 64000:
362  sbr_offset_ptr = sbr_offset[4];
363  break;
364  case 88200: case 96000: case 128000: case 176400: case 192000:
365  sbr_offset_ptr = sbr_offset[5];
366  break;
367  default:
368  av_log(ac->avctx, AV_LOG_ERROR,
369  "Unsupported sample rate for SBR: %d\n", sbr->sample_rate);
370  return -1;
371  }
372 
373  start_min = ((temp << 7) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
374  stop_min = ((temp << 8) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
375 
376  sbr->k[0] = start_min + sbr_offset_ptr[spectrum->bs_start_freq];
377 
378  if (spectrum->bs_stop_freq < 14) {
379  sbr->k[2] = stop_min;
380  make_bands(stop_dk, stop_min, 64, 13);
381  qsort(stop_dk, 13, sizeof(stop_dk[0]), qsort_comparison_function_int16);
382  for (k = 0; k < spectrum->bs_stop_freq; k++)
383  sbr->k[2] += stop_dk[k];
384  } else if (spectrum->bs_stop_freq == 14) {
385  sbr->k[2] = 2*sbr->k[0];
386  } else if (spectrum->bs_stop_freq == 15) {
387  sbr->k[2] = 3*sbr->k[0];
388  } else {
389  av_log(ac->avctx, AV_LOG_ERROR,
390  "Invalid bs_stop_freq: %d\n", spectrum->bs_stop_freq);
391  return -1;
392  }
393  sbr->k[2] = FFMIN(64, sbr->k[2]);
394 
395  // Requirements (14496-3 sp04 p205)
396  if (sbr->sample_rate <= 32000) {
397  max_qmf_subbands = 48;
398  } else if (sbr->sample_rate == 44100) {
399  max_qmf_subbands = 35;
400  } else if (sbr->sample_rate >= 48000)
401  max_qmf_subbands = 32;
402  else
403  av_assert0(0);
404 
405  if (sbr->k[2] - sbr->k[0] > max_qmf_subbands) {
406  av_log(ac->avctx, AV_LOG_ERROR,
407  "Invalid bitstream, too many QMF subbands: %d\n", sbr->k[2] - sbr->k[0]);
408  return -1;
409  }
410 
411  if (!spectrum->bs_freq_scale) {
412  int dk, k2diff;
413 
414  dk = spectrum->bs_alter_scale + 1;
415  sbr->n_master = ((sbr->k[2] - sbr->k[0] + (dk&2)) >> dk) << 1;
416  if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
417  return -1;
418 
419  for (k = 1; k <= sbr->n_master; k++)
420  sbr->f_master[k] = dk;
421 
422  k2diff = sbr->k[2] - sbr->k[0] - sbr->n_master * dk;
423  if (k2diff < 0) {
424  sbr->f_master[1]--;
425  sbr->f_master[2]-= (k2diff < -1);
426  } else if (k2diff) {
427  sbr->f_master[sbr->n_master]++;
428  }
429 
430  sbr->f_master[0] = sbr->k[0];
431  for (k = 1; k <= sbr->n_master; k++)
432  sbr->f_master[k] += sbr->f_master[k - 1];
433 
434  } else {
435  int half_bands = 7 - spectrum->bs_freq_scale; // bs_freq_scale = {1,2,3}
436  int two_regions, num_bands_0;
437  int vdk0_max, vdk1_min;
438  int16_t vk0[49];
439 
440  if (49 * sbr->k[2] > 110 * sbr->k[0]) {
441  two_regions = 1;
442  sbr->k[1] = 2 * sbr->k[0];
443  } else {
444  two_regions = 0;
445  sbr->k[1] = sbr->k[2];
446  }
447 
448  num_bands_0 = lrintf(half_bands * log2f(sbr->k[1] / (float)sbr->k[0])) * 2;
449 
450  if (num_bands_0 <= 0) { // Requirements (14496-3 sp04 p205)
451  av_log(ac->avctx, AV_LOG_ERROR, "Invalid num_bands_0: %d\n", num_bands_0);
452  return -1;
453  }
454 
455  vk0[0] = 0;
456 
457  make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
458 
459  qsort(vk0 + 1, num_bands_0, sizeof(vk0[1]), qsort_comparison_function_int16);
460  vdk0_max = vk0[num_bands_0];
461 
462  vk0[0] = sbr->k[0];
463  for (k = 1; k <= num_bands_0; k++) {
464  if (vk0[k] <= 0) { // Requirements (14496-3 sp04 p205)
465  av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk0[%d]: %d\n", k, vk0[k]);
466  return -1;
467  }
468  vk0[k] += vk0[k-1];
469  }
470 
471  if (two_regions) {
472  int16_t vk1[49];
473  float invwarp = spectrum->bs_alter_scale ? 0.76923076923076923077f
474  : 1.0f; // bs_alter_scale = {0,1}
475  int num_bands_1 = lrintf(half_bands * invwarp *
476  log2f(sbr->k[2] / (float)sbr->k[1])) * 2;
477 
478  make_bands(vk1+1, sbr->k[1], sbr->k[2], num_bands_1);
479 
480  vdk1_min = array_min_int16(vk1 + 1, num_bands_1);
481 
482  if (vdk1_min < vdk0_max) {
483  int change;
484  qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
485  change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1]) >> 1);
486  vk1[1] += change;
487  vk1[num_bands_1] -= change;
488  }
489 
490  qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
491 
492  vk1[0] = sbr->k[1];
493  for (k = 1; k <= num_bands_1; k++) {
494  if (vk1[k] <= 0) { // Requirements (14496-3 sp04 p205)
495  av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk1[%d]: %d\n", k, vk1[k]);
496  return -1;
497  }
498  vk1[k] += vk1[k-1];
499  }
500 
501  sbr->n_master = num_bands_0 + num_bands_1;
502  if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
503  return -1;
504  memcpy(&sbr->f_master[0], vk0,
505  (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
506  memcpy(&sbr->f_master[num_bands_0 + 1], vk1 + 1,
507  num_bands_1 * sizeof(sbr->f_master[0]));
508 
509  } else {
510  sbr->n_master = num_bands_0;
511  if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
512  return -1;
513  memcpy(sbr->f_master, vk0, (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
514  }
515  }
516 
517  return 0;
518 }
519 
520 /// High Frequency Generation - Patch Construction (14496-3 sp04 p216 fig. 4.46)
521 static int sbr_hf_calc_npatches(AACContext *ac, SpectralBandReplication *sbr)
522 {
523  int i, k, sb = 0;
524  int msb = sbr->k[0];
525  int usb = sbr->kx[1];
526  int goal_sb = ((1000 << 11) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
527 
528  sbr->num_patches = 0;
529 
530  if (goal_sb < sbr->kx[1] + sbr->m[1]) {
531  for (k = 0; sbr->f_master[k] < goal_sb; k++) ;
532  } else
533  k = sbr->n_master;
534 
535  do {
536  int odd = 0;
537  for (i = k; i == k || sb > (sbr->k[0] - 1 + msb - odd); i--) {
538  sb = sbr->f_master[i];
539  odd = (sb + sbr->k[0]) & 1;
540  }
541 
542  // Requirements (14496-3 sp04 p205) sets the maximum number of patches to 5.
543  // After this check the final number of patches can still be six which is
544  // illegal however the Coding Technologies decoder check stream has a final
545  // count of 6 patches
546  if (sbr->num_patches > 5) {
547  av_log(ac->avctx, AV_LOG_ERROR, "Too many patches: %d\n", sbr->num_patches);
548  return -1;
549  }
550 
551  sbr->patch_num_subbands[sbr->num_patches] = FFMAX(sb - usb, 0);
552  sbr->patch_start_subband[sbr->num_patches] = sbr->k[0] - odd - sbr->patch_num_subbands[sbr->num_patches];
553 
554  if (sbr->patch_num_subbands[sbr->num_patches] > 0) {
555  usb = sb;
556  msb = sb;
557  sbr->num_patches++;
558  } else
559  msb = sbr->kx[1];
560 
561  if (sbr->f_master[k] - sb < 3)
562  k = sbr->n_master;
563  } while (sb != sbr->kx[1] + sbr->m[1]);
564 
565  if (sbr->num_patches > 1 && sbr->patch_num_subbands[sbr->num_patches-1] < 3)
566  sbr->num_patches--;
567 
568  return 0;
569 }
570 
571 /// Derived Frequency Band Tables (14496-3 sp04 p197)
572 static int sbr_make_f_derived(AACContext *ac, SpectralBandReplication *sbr)
573 {
574  int k, temp;
575 
576  sbr->n[1] = sbr->n_master - sbr->spectrum_params.bs_xover_band;
577  sbr->n[0] = (sbr->n[1] + 1) >> 1;
578 
579  memcpy(sbr->f_tablehigh, &sbr->f_master[sbr->spectrum_params.bs_xover_band],
580  (sbr->n[1] + 1) * sizeof(sbr->f_master[0]));
581  sbr->m[1] = sbr->f_tablehigh[sbr->n[1]] - sbr->f_tablehigh[0];
582  sbr->kx[1] = sbr->f_tablehigh[0];
583 
584  // Requirements (14496-3 sp04 p205)
585  if (sbr->kx[1] + sbr->m[1] > 64) {
586  av_log(ac->avctx, AV_LOG_ERROR,
587  "Stop frequency border too high: %d\n", sbr->kx[1] + sbr->m[1]);
588  return -1;
589  }
590  if (sbr->kx[1] > 32) {
591  av_log(ac->avctx, AV_LOG_ERROR, "Start frequency border too high: %d\n", sbr->kx[1]);
592  return -1;
593  }
594 
595  sbr->f_tablelow[0] = sbr->f_tablehigh[0];
596  temp = sbr->n[1] & 1;
597  for (k = 1; k <= sbr->n[0]; k++)
598  sbr->f_tablelow[k] = sbr->f_tablehigh[2 * k - temp];
599 
600  sbr->n_q = FFMAX(1, lrintf(sbr->spectrum_params.bs_noise_bands *
601  log2f(sbr->k[2] / (float)sbr->kx[1]))); // 0 <= bs_noise_bands <= 3
602  if (sbr->n_q > 5) {
603  av_log(ac->avctx, AV_LOG_ERROR, "Too many noise floor scale factors: %d\n", sbr->n_q);
604  return -1;
605  }
606 
607  sbr->f_tablenoise[0] = sbr->f_tablelow[0];
608  temp = 0;
609  for (k = 1; k <= sbr->n_q; k++) {
610  temp += (sbr->n[0] - temp) / (sbr->n_q + 1 - k);
611  sbr->f_tablenoise[k] = sbr->f_tablelow[temp];
612  }
613 
614  if (sbr_hf_calc_npatches(ac, sbr) < 0)
615  return -1;
616 
617  sbr_make_f_tablelim(sbr);
618 
619  sbr->data[0].f_indexnoise = 0;
620  sbr->data[1].f_indexnoise = 0;
621 
622  return 0;
623 }
624 
625 static av_always_inline void get_bits1_vector(GetBitContext *gb, uint8_t *vec,
626  int elements)
627 {
628  int i;
629  for (i = 0; i < elements; i++) {
630  vec[i] = get_bits1(gb);
631  }
632 }
633 
634 /** ceil(log2(index+1)) */
635 static const int8_t ceil_log2[] = {
636  0, 1, 2, 2, 3, 3,
637 };
638 
639 static int read_sbr_grid(AACContext *ac, SpectralBandReplication *sbr,
640  GetBitContext *gb, SBRData *ch_data)
641 {
642  int i;
643  unsigned bs_pointer = 0;
644  // frameLengthFlag ? 15 : 16; 960 sample length frames unsupported; this value is numTimeSlots
645  int abs_bord_trail = 16;
646  int num_rel_lead, num_rel_trail;
647  unsigned bs_num_env_old = ch_data->bs_num_env;
648 
649  ch_data->bs_freq_res[0] = ch_data->bs_freq_res[ch_data->bs_num_env];
650  ch_data->bs_amp_res = sbr->bs_amp_res_header;
651  ch_data->t_env_num_env_old = ch_data->t_env[bs_num_env_old];
652 
653  switch (ch_data->bs_frame_class = get_bits(gb, 2)) {
654  case FIXFIX:
655  ch_data->bs_num_env = 1 << get_bits(gb, 2);
656  num_rel_lead = ch_data->bs_num_env - 1;
657  if (ch_data->bs_num_env == 1)
658  ch_data->bs_amp_res = 0;
659 
660  if (ch_data->bs_num_env > 4) {
661  av_log(ac->avctx, AV_LOG_ERROR,
662  "Invalid bitstream, too many SBR envelopes in FIXFIX type SBR frame: %d\n",
663  ch_data->bs_num_env);
664  return -1;
665  }
666 
667  ch_data->t_env[0] = 0;
668  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
669 
670  abs_bord_trail = (abs_bord_trail + (ch_data->bs_num_env >> 1)) /
671  ch_data->bs_num_env;
672  for (i = 0; i < num_rel_lead; i++)
673  ch_data->t_env[i + 1] = ch_data->t_env[i] + abs_bord_trail;
674 
675  ch_data->bs_freq_res[1] = get_bits1(gb);
676  for (i = 1; i < ch_data->bs_num_env; i++)
677  ch_data->bs_freq_res[i + 1] = ch_data->bs_freq_res[1];
678  break;
679  case FIXVAR:
680  abs_bord_trail += get_bits(gb, 2);
681  num_rel_trail = get_bits(gb, 2);
682  ch_data->bs_num_env = num_rel_trail + 1;
683  ch_data->t_env[0] = 0;
684  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
685 
686  for (i = 0; i < num_rel_trail; i++)
687  ch_data->t_env[ch_data->bs_num_env - 1 - i] =
688  ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
689 
690  bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
691 
692  for (i = 0; i < ch_data->bs_num_env; i++)
693  ch_data->bs_freq_res[ch_data->bs_num_env - i] = get_bits1(gb);
694  break;
695  case VARFIX:
696  ch_data->t_env[0] = get_bits(gb, 2);
697  num_rel_lead = get_bits(gb, 2);
698  ch_data->bs_num_env = num_rel_lead + 1;
699  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
700 
701  for (i = 0; i < num_rel_lead; i++)
702  ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
703 
704  bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
705 
706  get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
707  break;
708  case VARVAR:
709  ch_data->t_env[0] = get_bits(gb, 2);
710  abs_bord_trail += get_bits(gb, 2);
711  num_rel_lead = get_bits(gb, 2);
712  num_rel_trail = get_bits(gb, 2);
713  ch_data->bs_num_env = num_rel_lead + num_rel_trail + 1;
714 
715  if (ch_data->bs_num_env > 5) {
716  av_log(ac->avctx, AV_LOG_ERROR,
717  "Invalid bitstream, too many SBR envelopes in VARVAR type SBR frame: %d\n",
718  ch_data->bs_num_env);
719  return -1;
720  }
721 
722  ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
723 
724  for (i = 0; i < num_rel_lead; i++)
725  ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
726  for (i = 0; i < num_rel_trail; i++)
727  ch_data->t_env[ch_data->bs_num_env - 1 - i] =
728  ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
729 
730  bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
731 
732  get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
733  break;
734  }
735 
736  if (bs_pointer > ch_data->bs_num_env + 1) {
737  av_log(ac->avctx, AV_LOG_ERROR,
738  "Invalid bitstream, bs_pointer points to a middle noise border outside the time borders table: %d\n",
739  bs_pointer);
740  return -1;
741  }
742 
743  for (i = 1; i <= ch_data->bs_num_env; i++) {
744  if (ch_data->t_env[i-1] > ch_data->t_env[i]) {
745  av_log(ac->avctx, AV_LOG_ERROR, "Non monotone time borders\n");
746  return -1;
747  }
748  }
749 
750  ch_data->bs_num_noise = (ch_data->bs_num_env > 1) + 1;
751 
752  ch_data->t_q[0] = ch_data->t_env[0];
753  ch_data->t_q[ch_data->bs_num_noise] = ch_data->t_env[ch_data->bs_num_env];
754  if (ch_data->bs_num_noise > 1) {
755  unsigned int idx;
756  if (ch_data->bs_frame_class == FIXFIX) {
757  idx = ch_data->bs_num_env >> 1;
758  } else if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
759  idx = ch_data->bs_num_env - FFMAX((int)bs_pointer - 1, 1);
760  } else { // VARFIX
761  if (!bs_pointer)
762  idx = 1;
763  else if (bs_pointer == 1)
764  idx = ch_data->bs_num_env - 1;
765  else // bs_pointer > 1
766  idx = bs_pointer - 1;
767  }
768  ch_data->t_q[1] = ch_data->t_env[idx];
769  }
770 
771  ch_data->e_a[0] = -(ch_data->e_a[1] != bs_num_env_old); // l_APrev
772  ch_data->e_a[1] = -1;
773  if ((ch_data->bs_frame_class & 1) && bs_pointer) { // FIXVAR or VARVAR and bs_pointer != 0
774  ch_data->e_a[1] = ch_data->bs_num_env + 1 - bs_pointer;
775  } else if ((ch_data->bs_frame_class == 2) && (bs_pointer > 1)) // VARFIX and bs_pointer > 1
776  ch_data->e_a[1] = bs_pointer - 1;
777 
778  return 0;
779 }
780 
781 static void copy_sbr_grid(SBRData *dst, const SBRData *src) {
782  //These variables are saved from the previous frame rather than copied
783  dst->bs_freq_res[0] = dst->bs_freq_res[dst->bs_num_env];
784  dst->t_env_num_env_old = dst->t_env[dst->bs_num_env];
785  dst->e_a[0] = -(dst->e_a[1] != dst->bs_num_env);
786 
787  //These variables are read from the bitstream and therefore copied
788  memcpy(dst->bs_freq_res+1, src->bs_freq_res+1, sizeof(dst->bs_freq_res)-sizeof(*dst->bs_freq_res));
789  memcpy(dst->t_env, src->t_env, sizeof(dst->t_env));
790  memcpy(dst->t_q, src->t_q, sizeof(dst->t_q));
791  dst->bs_num_env = src->bs_num_env;
792  dst->bs_amp_res = src->bs_amp_res;
793  dst->bs_num_noise = src->bs_num_noise;
794  dst->bs_frame_class = src->bs_frame_class;
795  dst->e_a[1] = src->e_a[1];
796 }
797 
798 /// Read how the envelope and noise floor data is delta coded
799 static void read_sbr_dtdf(SpectralBandReplication *sbr, GetBitContext *gb,
800  SBRData *ch_data)
801 {
802  get_bits1_vector(gb, ch_data->bs_df_env, ch_data->bs_num_env);
803  get_bits1_vector(gb, ch_data->bs_df_noise, ch_data->bs_num_noise);
804 }
805 
806 /// Read inverse filtering data
807 static void read_sbr_invf(SpectralBandReplication *sbr, GetBitContext *gb,
808  SBRData *ch_data)
809 {
810  int i;
811 
812  memcpy(ch_data->bs_invf_mode[1], ch_data->bs_invf_mode[0], 5 * sizeof(uint8_t));
813  for (i = 0; i < sbr->n_q; i++)
814  ch_data->bs_invf_mode[0][i] = get_bits(gb, 2);
815 }
816 
817 static void read_sbr_envelope(SpectralBandReplication *sbr, GetBitContext *gb,
818  SBRData *ch_data, int ch)
819 {
820  int bits;
821  int i, j, k;
822  VLC_TYPE (*t_huff)[2], (*f_huff)[2];
823  int t_lav, f_lav;
824  const int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
825  const int odd = sbr->n[1] & 1;
826 
827  if (sbr->bs_coupling && ch) {
828  if (ch_data->bs_amp_res) {
829  bits = 5;
830  t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_3_0DB].table;
831  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_3_0DB];
832  f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
833  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
834  } else {
835  bits = 6;
836  t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_1_5DB].table;
837  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_1_5DB];
838  f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_1_5DB].table;
839  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_1_5DB];
840  }
841  } else {
842  if (ch_data->bs_amp_res) {
843  bits = 6;
844  t_huff = vlc_sbr[T_HUFFMAN_ENV_3_0DB].table;
845  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_3_0DB];
846  f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
847  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
848  } else {
849  bits = 7;
850  t_huff = vlc_sbr[T_HUFFMAN_ENV_1_5DB].table;
851  t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_1_5DB];
852  f_huff = vlc_sbr[F_HUFFMAN_ENV_1_5DB].table;
853  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_1_5DB];
854  }
855  }
856 
857  for (i = 0; i < ch_data->bs_num_env; i++) {
858  if (ch_data->bs_df_env[i]) {
859  // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
860  if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
861  for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
862  ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
863  } else if (ch_data->bs_freq_res[i + 1]) {
864  for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
865  k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
866  ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
867  }
868  } else {
869  for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
870  k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
871  ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
872  }
873  }
874  } else {
875  ch_data->env_facs[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
876  for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
877  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);
878  }
879  }
880 
881  //assign 0th elements of env_facs from last elements
882  memcpy(ch_data->env_facs[0], ch_data->env_facs[ch_data->bs_num_env],
883  sizeof(ch_data->env_facs[0]));
884 }
885 
886 static void read_sbr_noise(SpectralBandReplication *sbr, GetBitContext *gb,
887  SBRData *ch_data, int ch)
888 {
889  int i, j;
890  VLC_TYPE (*t_huff)[2], (*f_huff)[2];
891  int t_lav, f_lav;
892  int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
893 
894  if (sbr->bs_coupling && ch) {
895  t_huff = vlc_sbr[T_HUFFMAN_NOISE_BAL_3_0DB].table;
896  t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_BAL_3_0DB];
897  f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
898  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
899  } else {
900  t_huff = vlc_sbr[T_HUFFMAN_NOISE_3_0DB].table;
901  t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_3_0DB];
902  f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
903  f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
904  }
905 
906  for (i = 0; i < ch_data->bs_num_noise; i++) {
907  if (ch_data->bs_df_noise[i]) {
908  for (j = 0; j < sbr->n_q; j++)
909  ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 2) - t_lav);
910  } else {
911  ch_data->noise_facs[i + 1][0] = delta * get_bits(gb, 5); // bs_noise_start_value_balance or bs_noise_start_value_level
912  for (j = 1; j < sbr->n_q; j++)
913  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);
914  }
915  }
916 
917  //assign 0th elements of noise_facs from last elements
918  memcpy(ch_data->noise_facs[0], ch_data->noise_facs[ch_data->bs_num_noise],
919  sizeof(ch_data->noise_facs[0]));
920 }
921 
922 static void read_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
923  GetBitContext *gb,
924  int bs_extension_id, int *num_bits_left)
925 {
926  switch (bs_extension_id) {
927  case EXTENSION_ID_PS:
928  if (!ac->oc[1].m4ac.ps) {
929  av_log(ac->avctx, AV_LOG_ERROR, "Parametric Stereo signaled to be not-present but was found in the bitstream.\n");
930  skip_bits_long(gb, *num_bits_left); // bs_fill_bits
931  *num_bits_left = 0;
932  } else {
933 #if 1
934  *num_bits_left -= ff_ps_read_data(ac->avctx, gb, &sbr->ps, *num_bits_left);
935 #else
936  avpriv_report_missing_feature(ac->avctx, "Parametric Stereo");
937  skip_bits_long(gb, *num_bits_left); // bs_fill_bits
938  *num_bits_left = 0;
939 #endif
940  }
941  break;
942  default:
943  // some files contain 0-padding
944  if (bs_extension_id || *num_bits_left > 16 || show_bits(gb, *num_bits_left))
945  avpriv_request_sample(ac->avctx, "Reserved SBR extensions");
946  skip_bits_long(gb, *num_bits_left); // bs_fill_bits
947  *num_bits_left = 0;
948  break;
949  }
950 }
951 
952 static int read_sbr_single_channel_element(AACContext *ac,
953  SpectralBandReplication *sbr,
954  GetBitContext *gb)
955 {
956  if (get_bits1(gb)) // bs_data_extra
957  skip_bits(gb, 4); // bs_reserved
958 
959  if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
960  return -1;
961  read_sbr_dtdf(sbr, gb, &sbr->data[0]);
962  read_sbr_invf(sbr, gb, &sbr->data[0]);
963  read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
964  read_sbr_noise(sbr, gb, &sbr->data[0], 0);
965 
966  if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
967  get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
968 
969  return 0;
970 }
971 
972 static int read_sbr_channel_pair_element(AACContext *ac,
973  SpectralBandReplication *sbr,
974  GetBitContext *gb)
975 {
976  if (get_bits1(gb)) // bs_data_extra
977  skip_bits(gb, 8); // bs_reserved
978 
979  if ((sbr->bs_coupling = get_bits1(gb))) {
980  if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
981  return -1;
982  copy_sbr_grid(&sbr->data[1], &sbr->data[0]);
983  read_sbr_dtdf(sbr, gb, &sbr->data[0]);
984  read_sbr_dtdf(sbr, gb, &sbr->data[1]);
985  read_sbr_invf(sbr, gb, &sbr->data[0]);
986  memcpy(sbr->data[1].bs_invf_mode[1], sbr->data[1].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
987  memcpy(sbr->data[1].bs_invf_mode[0], sbr->data[0].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
988  read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
989  read_sbr_noise(sbr, gb, &sbr->data[0], 0);
990  read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
991  read_sbr_noise(sbr, gb, &sbr->data[1], 1);
992  } else {
993  if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]) ||
994  read_sbr_grid(ac, sbr, gb, &sbr->data[1]))
995  return -1;
996  read_sbr_dtdf(sbr, gb, &sbr->data[0]);
997  read_sbr_dtdf(sbr, gb, &sbr->data[1]);
998  read_sbr_invf(sbr, gb, &sbr->data[0]);
999  read_sbr_invf(sbr, gb, &sbr->data[1]);
1000  read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
1001  read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
1002  read_sbr_noise(sbr, gb, &sbr->data[0], 0);
1003  read_sbr_noise(sbr, gb, &sbr->data[1], 1);
1004  }
1005 
1006  if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
1007  get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
1008  if ((sbr->data[1].bs_add_harmonic_flag = get_bits1(gb)))
1009  get_bits1_vector(gb, sbr->data[1].bs_add_harmonic, sbr->n[1]);
1010 
1011  return 0;
1012 }
1013 
1014 static unsigned int read_sbr_data(AACContext *ac, SpectralBandReplication *sbr,
1015  GetBitContext *gb, int id_aac)
1016 {
1017  unsigned int cnt = get_bits_count(gb);
1018 
1019  if (id_aac == TYPE_SCE || id_aac == TYPE_CCE) {
1020  if (read_sbr_single_channel_element(ac, sbr, gb)) {
1021  sbr_turnoff(sbr);
1022  return get_bits_count(gb) - cnt;
1023  }
1024  } else if (id_aac == TYPE_CPE) {
1025  if (read_sbr_channel_pair_element(ac, sbr, gb)) {
1026  sbr_turnoff(sbr);
1027  return get_bits_count(gb) - cnt;
1028  }
1029  } else {
1030  av_log(ac->avctx, AV_LOG_ERROR,
1031  "Invalid bitstream - cannot apply SBR to element type %d\n", id_aac);
1032  sbr_turnoff(sbr);
1033  return get_bits_count(gb) - cnt;
1034  }
1035  if (get_bits1(gb)) { // bs_extended_data
1036  int num_bits_left = get_bits(gb, 4); // bs_extension_size
1037  if (num_bits_left == 15)
1038  num_bits_left += get_bits(gb, 8); // bs_esc_count
1039 
1040  num_bits_left <<= 3;
1041  while (num_bits_left > 7) {
1042  num_bits_left -= 2;
1043  read_sbr_extension(ac, sbr, gb, get_bits(gb, 2), &num_bits_left); // bs_extension_id
1044  }
1045  if (num_bits_left < 0) {
1046  av_log(ac->avctx, AV_LOG_ERROR, "SBR Extension over read.\n");
1047  }
1048  if (num_bits_left > 0)
1049  skip_bits(gb, num_bits_left);
1050  }
1051 
1052  return get_bits_count(gb) - cnt;
1053 }
1054 
1055 static void sbr_reset(AACContext *ac, SpectralBandReplication *sbr)
1056 {
1057  int err;
1058  err = sbr_make_f_master(ac, sbr, &sbr->spectrum_params);
1059  if (err >= 0)
1060  err = sbr_make_f_derived(ac, sbr);
1061  if (err < 0) {
1062  av_log(ac->avctx, AV_LOG_ERROR,
1063  "SBR reset failed. Switching SBR to pure upsampling mode.\n");
1064  sbr_turnoff(sbr);
1065  }
1066 }
1067 
1068 /**
1069  * Decode Spectral Band Replication extension data; reference: table 4.55.
1070  *
1071  * @param crc flag indicating the presence of CRC checksum
1072  * @param cnt length of TYPE_FIL syntactic element in bytes
1073  *
1074  * @return Returns number of bytes consumed from the TYPE_FIL element.
1075  */
1076 int ff_decode_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
1077  GetBitContext *gb_host, int crc, int cnt, int id_aac)
1078 {
1079  unsigned int num_sbr_bits = 0, num_align_bits;
1080  unsigned bytes_read;
1081  GetBitContext gbc = *gb_host, *gb = &gbc;
1082  skip_bits_long(gb_host, cnt*8 - 4);
1083 
1084  sbr->reset = 0;
1085 
1086  if (!sbr->sample_rate)
1087  sbr->sample_rate = 2 * ac->oc[1].m4ac.sample_rate; //TODO use the nominal sample rate for arbitrary sample rate support
1088  if (!ac->oc[1].m4ac.ext_sample_rate)
1089  ac->oc[1].m4ac.ext_sample_rate = 2 * ac->oc[1].m4ac.sample_rate;
1090 
1091  if (crc) {
1092  skip_bits(gb, 10); // bs_sbr_crc_bits; TODO - implement CRC check
1093  num_sbr_bits += 10;
1094  }
1095 
1096  //Save some state from the previous frame.
1097  sbr->kx[0] = sbr->kx[1];
1098  sbr->m[0] = sbr->m[1];
1099  sbr->kx_and_m_pushed = 1;
1100 
1101  num_sbr_bits++;
1102  if (get_bits1(gb)) // bs_header_flag
1103  num_sbr_bits += read_sbr_header(sbr, gb);
1104 
1105  if (sbr->reset)
1106  sbr_reset(ac, sbr);
1107 
1108  if (sbr->start)
1109  num_sbr_bits += read_sbr_data(ac, sbr, gb, id_aac);
1110 
1111  num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
1112  bytes_read = ((num_sbr_bits + num_align_bits + 4) >> 3);
1113 
1114  if (bytes_read > cnt) {
1115  av_log(ac->avctx, AV_LOG_ERROR,
1116  "Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
1117  }
1118  return cnt;
1119 }
1120 
1121 /// Dequantization and stereo decoding (14496-3 sp04 p203)
1122 static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
1123 {
1124  int k, e;
1125  int ch;
1126 
1127  if (id_aac == TYPE_CPE && sbr->bs_coupling) {
1128  float alpha = sbr->data[0].bs_amp_res ? 1.0f : 0.5f;
1129  float pan_offset = sbr->data[0].bs_amp_res ? 12.0f : 24.0f;
1130  for (e = 1; e <= sbr->data[0].bs_num_env; e++) {
1131  for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
1132  float temp1 = exp2f(sbr->data[0].env_facs[e][k] * alpha + 7.0f);
1133  float temp2 = exp2f((pan_offset - sbr->data[1].env_facs[e][k]) * alpha);
1134  float fac;
1135  if (temp1 > 1E20) {
1136  av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
1137  temp1 = 1;
1138  }
1139  fac = temp1 / (1.0f + temp2);
1140  sbr->data[0].env_facs[e][k] = fac;
1141  sbr->data[1].env_facs[e][k] = fac * temp2;
1142  }
1143  }
1144  for (e = 1; e <= sbr->data[0].bs_num_noise; e++) {
1145  for (k = 0; k < sbr->n_q; k++) {
1146  float temp1 = exp2f(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs[e][k] + 1);
1147  float temp2 = exp2f(12 - sbr->data[1].noise_facs[e][k]);
1148  float fac;
1149  if (temp1 > 1E20) {
1150  av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
1151  temp1 = 1;
1152  }
1153  fac = temp1 / (1.0f + temp2);
1154  sbr->data[0].noise_facs[e][k] = fac;
1155  sbr->data[1].noise_facs[e][k] = fac * temp2;
1156  }
1157  }
1158  } else { // SCE or one non-coupled CPE
1159  for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) {
1160  float alpha = sbr->data[ch].bs_amp_res ? 1.0f : 0.5f;
1161  for (e = 1; e <= sbr->data[ch].bs_num_env; e++)
1162  for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++){
1163  sbr->data[ch].env_facs[e][k] =
1164  exp2f(alpha * sbr->data[ch].env_facs[e][k] + 6.0f);
1165  if (sbr->data[ch].env_facs[e][k] > 1E20) {
1166  av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
1167  sbr->data[ch].env_facs[e][k] = 1;
1168  }
1169  }
1170 
1171  for (e = 1; e <= sbr->data[ch].bs_num_noise; e++)
1172  for (k = 0; k < sbr->n_q; k++)
1173  sbr->data[ch].noise_facs[e][k] =
1174  exp2f(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs[e][k]);
1175  }
1176  }
1177 }
1178 
1179 /**
1180  * Analysis QMF Bank (14496-3 sp04 p206)
1181  *
1182  * @param x pointer to the beginning of the first sample window
1183  * @param W array of complex-valued samples split into subbands
1184  */
1185 #ifndef sbr_qmf_analysis
1186 static void sbr_qmf_analysis(AVFloatDSPContext *dsp, FFTContext *mdct,
1187  SBRDSPContext *sbrdsp, const float *in, float *x,
1188  float z[320], float W[2][32][32][2], int buf_idx)
1189 {
1190  int i;
1191  memcpy(x , x+1024, (320-32)*sizeof(x[0]));
1192  memcpy(x+288, in, 1024*sizeof(x[0]));
1193  for (i = 0; i < 32; i++) { // numTimeSlots*RATE = 16*2 as 960 sample frames
1194  // are not supported
1195  dsp->vector_fmul_reverse(z, sbr_qmf_window_ds, x, 320);
1196  sbrdsp->sum64x5(z);
1197  sbrdsp->qmf_pre_shuffle(z);
1198  mdct->imdct_half(mdct, z, z+64);
1199  sbrdsp->qmf_post_shuffle(W[buf_idx][i], z);
1200  x += 32;
1201  }
1202 }
1203 #endif
1204 
1205 /**
1206  * Synthesis QMF Bank (14496-3 sp04 p206) and Downsampled Synthesis QMF Bank
1207  * (14496-3 sp04 p206)
1208  */
1209 #ifndef sbr_qmf_synthesis
1210 static void sbr_qmf_synthesis(FFTContext *mdct,
1211  SBRDSPContext *sbrdsp, AVFloatDSPContext *dsp,
1212  float *out, float X[2][38][64],
1213  float mdct_buf[2][64],
1214  float *v0, int *v_off, const unsigned int div)
1215 {
1216  int i, n;
1217  const float *sbr_qmf_window = div ? sbr_qmf_window_ds : sbr_qmf_window_us;
1218  const int step = 128 >> div;
1219  float *v;
1220  for (i = 0; i < 32; i++) {
1221  if (*v_off < step) {
1222  int saved_samples = (1280 - 128) >> div;
1223  memcpy(&v0[SBR_SYNTHESIS_BUF_SIZE - saved_samples], v0, saved_samples * sizeof(float));
1224  *v_off = SBR_SYNTHESIS_BUF_SIZE - saved_samples - step;
1225  } else {
1226  *v_off -= step;
1227  }
1228  v = v0 + *v_off;
1229  if (div) {
1230  for (n = 0; n < 32; n++) {
1231  X[0][i][ n] = -X[0][i][n];
1232  X[0][i][32+n] = X[1][i][31-n];
1233  }
1234  mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1235  sbrdsp->qmf_deint_neg(v, mdct_buf[0]);
1236  } else {
1237  sbrdsp->neg_odd_64(X[1][i]);
1238  mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1239  mdct->imdct_half(mdct, mdct_buf[1], X[1][i]);
1240  sbrdsp->qmf_deint_bfly(v, mdct_buf[1], mdct_buf[0]);
1241  }
1242  dsp->vector_fmul (out, v , sbr_qmf_window , 64 >> div);
1243  dsp->vector_fmul_add(out, v + ( 192 >> div), sbr_qmf_window + ( 64 >> div), out , 64 >> div);
1244  dsp->vector_fmul_add(out, v + ( 256 >> div), sbr_qmf_window + (128 >> div), out , 64 >> div);
1245  dsp->vector_fmul_add(out, v + ( 448 >> div), sbr_qmf_window + (192 >> div), out , 64 >> div);
1246  dsp->vector_fmul_add(out, v + ( 512 >> div), sbr_qmf_window + (256 >> div), out , 64 >> div);
1247  dsp->vector_fmul_add(out, v + ( 704 >> div), sbr_qmf_window + (320 >> div), out , 64 >> div);
1248  dsp->vector_fmul_add(out, v + ( 768 >> div), sbr_qmf_window + (384 >> div), out , 64 >> div);
1249  dsp->vector_fmul_add(out, v + ( 960 >> div), sbr_qmf_window + (448 >> div), out , 64 >> div);
1250  dsp->vector_fmul_add(out, v + (1024 >> div), sbr_qmf_window + (512 >> div), out , 64 >> div);
1251  dsp->vector_fmul_add(out, v + (1216 >> div), sbr_qmf_window + (576 >> div), out , 64 >> div);
1252  out += 64 >> div;
1253  }
1254 }
1255 #endif
1256 
1257 /** High Frequency Generation (14496-3 sp04 p214+) and Inverse Filtering
1258  * (14496-3 sp04 p214)
1259  * Warning: This routine does not seem numerically stable.
1260  */
1261 static void sbr_hf_inverse_filter(SBRDSPContext *dsp,
1262  float (*alpha0)[2], float (*alpha1)[2],
1263  const float X_low[32][40][2], int k0)
1264 {
1265  int k;
1266  for (k = 0; k < k0; k++) {
1267  LOCAL_ALIGNED_16(float, phi, [3], [2][2]);
1268  float dk;
1269 
1270  dsp->autocorrelate(X_low[k], phi);
1271 
1272  dk = phi[2][1][0] * phi[1][0][0] -
1273  (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f;
1274 
1275  if (!dk) {
1276  alpha1[k][0] = 0;
1277  alpha1[k][1] = 0;
1278  } else {
1279  float temp_real, temp_im;
1280  temp_real = phi[0][0][0] * phi[1][1][0] -
1281  phi[0][0][1] * phi[1][1][1] -
1282  phi[0][1][0] * phi[1][0][0];
1283  temp_im = phi[0][0][0] * phi[1][1][1] +
1284  phi[0][0][1] * phi[1][1][0] -
1285  phi[0][1][1] * phi[1][0][0];
1286 
1287  alpha1[k][0] = temp_real / dk;
1288  alpha1[k][1] = temp_im / dk;
1289  }
1290 
1291  if (!phi[1][0][0]) {
1292  alpha0[k][0] = 0;
1293  alpha0[k][1] = 0;
1294  } else {
1295  float temp_real, temp_im;
1296  temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] +
1297  alpha1[k][1] * phi[1][1][1];
1298  temp_im = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] -
1299  alpha1[k][0] * phi[1][1][1];
1300 
1301  alpha0[k][0] = -temp_real / phi[1][0][0];
1302  alpha0[k][1] = -temp_im / phi[1][0][0];
1303  }
1304 
1305  if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f ||
1306  alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) {
1307  alpha1[k][0] = 0;
1308  alpha1[k][1] = 0;
1309  alpha0[k][0] = 0;
1310  alpha0[k][1] = 0;
1311  }
1312  }
1313 }
1314 
1315 /// Chirp Factors (14496-3 sp04 p214)
1316 static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data)
1317 {
1318  int i;
1319  float new_bw;
1320  static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f };
1321 
1322  for (i = 0; i < sbr->n_q; i++) {
1323  if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) {
1324  new_bw = 0.6f;
1325  } else
1326  new_bw = bw_tab[ch_data->bs_invf_mode[0][i]];
1327 
1328  if (new_bw < ch_data->bw_array[i]) {
1329  new_bw = 0.75f * new_bw + 0.25f * ch_data->bw_array[i];
1330  } else
1331  new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i];
1332  ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw;
1333  }
1334 }
1335 
1336 /// Generate the subband filtered lowband
1337 static int sbr_lf_gen(AACContext *ac, SpectralBandReplication *sbr,
1338  float X_low[32][40][2], const float W[2][32][32][2],
1339  int buf_idx)
1340 {
1341  int i, k;
1342  const int t_HFGen = 8;
1343  const int i_f = 32;
1344  memset(X_low, 0, 32*sizeof(*X_low));
1345  for (k = 0; k < sbr->kx[1]; k++) {
1346  for (i = t_HFGen; i < i_f + t_HFGen; i++) {
1347  X_low[k][i][0] = W[buf_idx][i - t_HFGen][k][0];
1348  X_low[k][i][1] = W[buf_idx][i - t_HFGen][k][1];
1349  }
1350  }
1351  buf_idx = 1-buf_idx;
1352  for (k = 0; k < sbr->kx[0]; k++) {
1353  for (i = 0; i < t_HFGen; i++) {
1354  X_low[k][i][0] = W[buf_idx][i + i_f - t_HFGen][k][0];
1355  X_low[k][i][1] = W[buf_idx][i + i_f - t_HFGen][k][1];
1356  }
1357  }
1358  return 0;
1359 }
1360 
1361 /// High Frequency Generator (14496-3 sp04 p215)
1362 static int sbr_hf_gen(AACContext *ac, SpectralBandReplication *sbr,
1363  float X_high[64][40][2], const float X_low[32][40][2],
1364  const float (*alpha0)[2], const float (*alpha1)[2],
1365  const float bw_array[5], const uint8_t *t_env,
1366  int bs_num_env)
1367 {
1368  int j, x;
1369  int g = 0;
1370  int k = sbr->kx[1];
1371  for (j = 0; j < sbr->num_patches; j++) {
1372  for (x = 0; x < sbr->patch_num_subbands[j]; x++, k++) {
1373  const int p = sbr->patch_start_subband[j] + x;
1374  while (g <= sbr->n_q && k >= sbr->f_tablenoise[g])
1375  g++;
1376  g--;
1377 
1378  if (g < 0) {
1379  av_log(ac->avctx, AV_LOG_ERROR,
1380  "ERROR : no subband found for frequency %d\n", k);
1381  return -1;
1382  }
1383 
1384  sbr->dsp.hf_gen(X_high[k] + ENVELOPE_ADJUSTMENT_OFFSET,
1385  X_low[p] + ENVELOPE_ADJUSTMENT_OFFSET,
1386  alpha0[p], alpha1[p], bw_array[g],
1387  2 * t_env[0], 2 * t_env[bs_num_env]);
1388  }
1389  }
1390  if (k < sbr->m[1] + sbr->kx[1])
1391  memset(X_high + k, 0, (sbr->m[1] + sbr->kx[1] - k) * sizeof(*X_high));
1392 
1393  return 0;
1394 }
1395 
1396 /// Generate the subband filtered lowband
1397 static int sbr_x_gen(SpectralBandReplication *sbr, float X[2][38][64],
1398  const float Y0[38][64][2], const float Y1[38][64][2],
1399  const float X_low[32][40][2], int ch)
1400 {
1401  int k, i;
1402  const int i_f = 32;
1403  const int i_Temp = FFMAX(2*sbr->data[ch].t_env_num_env_old - i_f, 0);
1404  memset(X, 0, 2*sizeof(*X));
1405  for (k = 0; k < sbr->kx[0]; k++) {
1406  for (i = 0; i < i_Temp; i++) {
1407  X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1408  X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1409  }
1410  }
1411  for (; k < sbr->kx[0] + sbr->m[0]; k++) {
1412  for (i = 0; i < i_Temp; i++) {
1413  X[0][i][k] = Y0[i + i_f][k][0];
1414  X[1][i][k] = Y0[i + i_f][k][1];
1415  }
1416  }
1417 
1418  for (k = 0; k < sbr->kx[1]; k++) {
1419  for (i = i_Temp; i < 38; i++) {
1420  X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1421  X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1422  }
1423  }
1424  for (; k < sbr->kx[1] + sbr->m[1]; k++) {
1425  for (i = i_Temp; i < i_f; i++) {
1426  X[0][i][k] = Y1[i][k][0];
1427  X[1][i][k] = Y1[i][k][1];
1428  }
1429  }
1430  return 0;
1431 }
1432 
1433 /** High Frequency Adjustment (14496-3 sp04 p217) and Mapping
1434  * (14496-3 sp04 p217)
1435  */
1436 static int sbr_mapping(AACContext *ac, SpectralBandReplication *sbr,
1437  SBRData *ch_data, int e_a[2])
1438 {
1439  int e, i, m;
1440 
1441  memset(ch_data->s_indexmapped[1], 0, 7*sizeof(ch_data->s_indexmapped[1]));
1442  for (e = 0; e < ch_data->bs_num_env; e++) {
1443  const unsigned int ilim = sbr->n[ch_data->bs_freq_res[e + 1]];
1444  uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1445  int k;
1446 
1447  if (sbr->kx[1] != table[0]) {
1448  av_log(ac->avctx, AV_LOG_ERROR, "kx != f_table{high,low}[0]. "
1449  "Derived frequency tables were not regenerated.\n");
1450  sbr_turnoff(sbr);
1451  return AVERROR_BUG;
1452  }
1453  for (i = 0; i < ilim; i++)
1454  for (m = table[i]; m < table[i + 1]; m++)
1455  sbr->e_origmapped[e][m - sbr->kx[1]] = ch_data->env_facs[e+1][i];
1456 
1457  // ch_data->bs_num_noise > 1 => 2 noise floors
1458  k = (ch_data->bs_num_noise > 1) && (ch_data->t_env[e] >= ch_data->t_q[1]);
1459  for (i = 0; i < sbr->n_q; i++)
1460  for (m = sbr->f_tablenoise[i]; m < sbr->f_tablenoise[i + 1]; m++)
1461  sbr->q_mapped[e][m - sbr->kx[1]] = ch_data->noise_facs[k+1][i];
1462 
1463  for (i = 0; i < sbr->n[1]; i++) {
1464  if (ch_data->bs_add_harmonic_flag) {
1465  const unsigned int m_midpoint =
1466  (sbr->f_tablehigh[i] + sbr->f_tablehigh[i + 1]) >> 1;
1467 
1468  ch_data->s_indexmapped[e + 1][m_midpoint - sbr->kx[1]] = ch_data->bs_add_harmonic[i] *
1469  (e >= e_a[1] || (ch_data->s_indexmapped[0][m_midpoint - sbr->kx[1]] == 1));
1470  }
1471  }
1472 
1473  for (i = 0; i < ilim; i++) {
1474  int additional_sinusoid_present = 0;
1475  for (m = table[i]; m < table[i + 1]; m++) {
1476  if (ch_data->s_indexmapped[e + 1][m - sbr->kx[1]]) {
1477  additional_sinusoid_present = 1;
1478  break;
1479  }
1480  }
1481  memset(&sbr->s_mapped[e][table[i] - sbr->kx[1]], additional_sinusoid_present,
1482  (table[i + 1] - table[i]) * sizeof(sbr->s_mapped[e][0]));
1483  }
1484  }
1485 
1486  memcpy(ch_data->s_indexmapped[0], ch_data->s_indexmapped[ch_data->bs_num_env], sizeof(ch_data->s_indexmapped[0]));
1487  return 0;
1488 }
1489 
1490 /// Estimation of current envelope (14496-3 sp04 p218)
1491 static void sbr_env_estimate(float (*e_curr)[48], float X_high[64][40][2],
1492  SpectralBandReplication *sbr, SBRData *ch_data)
1493 {
1494  int e, m;
1495  int kx1 = sbr->kx[1];
1496 
1497  if (sbr->bs_interpol_freq) {
1498  for (e = 0; e < ch_data->bs_num_env; e++) {
1499  const float recip_env_size = 0.5f / (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1500  int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1501  int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1502 
1503  for (m = 0; m < sbr->m[1]; m++) {
1504  float sum = sbr->dsp.sum_square(X_high[m+kx1] + ilb, iub - ilb);
1505  e_curr[e][m] = sum * recip_env_size;
1506  }
1507  }
1508  } else {
1509  int k, p;
1510 
1511  for (e = 0; e < ch_data->bs_num_env; e++) {
1512  const int env_size = 2 * (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1513  int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1514  int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1515  const uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1516 
1517  for (p = 0; p < sbr->n[ch_data->bs_freq_res[e + 1]]; p++) {
1518  float sum = 0.0f;
1519  const int den = env_size * (table[p + 1] - table[p]);
1520 
1521  for (k = table[p]; k < table[p + 1]; k++) {
1522  sum += sbr->dsp.sum_square(X_high[k] + ilb, iub - ilb);
1523  }
1524  sum /= den;
1525  for (k = table[p]; k < table[p + 1]; k++) {
1526  e_curr[e][k - kx1] = sum;
1527  }
1528  }
1529  }
1530  }
1531 }
1532 
1533 /**
1534  * Calculation of levels of additional HF signal components (14496-3 sp04 p219)
1535  * and Calculation of gain (14496-3 sp04 p219)
1536  */
1537 static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr,
1538  SBRData *ch_data, const int e_a[2])
1539 {
1540  int e, k, m;
1541  // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off)
1542  static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 };
1543 
1544  for (e = 0; e < ch_data->bs_num_env; e++) {
1545  int delta = !((e == e_a[1]) || (e == e_a[0]));
1546  for (k = 0; k < sbr->n_lim; k++) {
1547  float gain_boost, gain_max;
1548  float sum[2] = { 0.0f, 0.0f };
1549  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1550  const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]);
1551  sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]);
1552  sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]);
1553  if (!sbr->s_mapped[e][m]) {
1554  sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] /
1555  ((1.0f + sbr->e_curr[e][m]) *
1556  (1.0f + sbr->q_mapped[e][m] * delta)));
1557  } else {
1558  sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] /
1559  ((1.0f + sbr->e_curr[e][m]) *
1560  (1.0f + sbr->q_mapped[e][m])));
1561  }
1562  }
1563  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1564  sum[0] += sbr->e_origmapped[e][m];
1565  sum[1] += sbr->e_curr[e][m];
1566  }
1567  gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1568  gain_max = FFMIN(100000.f, gain_max);
1569  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1570  float q_m_max = sbr->q_m[e][m] * gain_max / sbr->gain[e][m];
1571  sbr->q_m[e][m] = FFMIN(sbr->q_m[e][m], q_m_max);
1572  sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max);
1573  }
1574  sum[0] = sum[1] = 0.0f;
1575  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1576  sum[0] += sbr->e_origmapped[e][m];
1577  sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m]
1578  + sbr->s_m[e][m] * sbr->s_m[e][m]
1579  + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m];
1580  }
1581  gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1582  gain_boost = FFMIN(1.584893192f, gain_boost);
1583  for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1584  sbr->gain[e][m] *= gain_boost;
1585  sbr->q_m[e][m] *= gain_boost;
1586  sbr->s_m[e][m] *= gain_boost;
1587  }
1588  }
1589  }
1590 }
1591 
1592 /// Assembling HF Signals (14496-3 sp04 p220)
1593 static void sbr_hf_assemble(float Y1[38][64][2],
1594  const float X_high[64][40][2],
1595  SpectralBandReplication *sbr, SBRData *ch_data,
1596  const int e_a[2])
1597 {
1598  int e, i, j, m;
1599  const int h_SL = 4 * !sbr->bs_smoothing_mode;
1600  const int kx = sbr->kx[1];
1601  const int m_max = sbr->m[1];
1602  static const float h_smooth[5] = {
1603  0.33333333333333,
1604  0.30150283239582,
1605  0.21816949906249,
1606  0.11516383427084,
1607  0.03183050093751,
1608  };
1609  float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp;
1610  int indexnoise = ch_data->f_indexnoise;
1611  int indexsine = ch_data->f_indexsine;
1612 
1613  if (sbr->reset) {
1614  for (i = 0; i < h_SL; i++) {
1615  memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0]));
1616  memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0], m_max * sizeof(sbr->q_m[0][0]));
1617  }
1618  } else if (h_SL) {
1619  memcpy(g_temp[2*ch_data->t_env[0]], g_temp[2*ch_data->t_env_num_env_old], 4*sizeof(g_temp[0]));
1620  memcpy(q_temp[2*ch_data->t_env[0]], q_temp[2*ch_data->t_env_num_env_old], 4*sizeof(q_temp[0]));
1621  }
1622 
1623  for (e = 0; e < ch_data->bs_num_env; e++) {
1624  for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1625  memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0]));
1626  memcpy(q_temp[h_SL + i], sbr->q_m[e], m_max * sizeof(sbr->q_m[0][0]));
1627  }
1628  }
1629 
1630  for (e = 0; e < ch_data->bs_num_env; e++) {
1631  for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1632  LOCAL_ALIGNED_16(float, g_filt_tab, [48]);
1633  LOCAL_ALIGNED_16(float, q_filt_tab, [48]);
1634  float *g_filt, *q_filt;
1635 
1636  if (h_SL && e != e_a[0] && e != e_a[1]) {
1637  g_filt = g_filt_tab;
1638  q_filt = q_filt_tab;
1639  for (m = 0; m < m_max; m++) {
1640  const int idx1 = i + h_SL;
1641  g_filt[m] = 0.0f;
1642  q_filt[m] = 0.0f;
1643  for (j = 0; j <= h_SL; j++) {
1644  g_filt[m] += g_temp[idx1 - j][m] * h_smooth[j];
1645  q_filt[m] += q_temp[idx1 - j][m] * h_smooth[j];
1646  }
1647  }
1648  } else {
1649  g_filt = g_temp[i + h_SL];
1650  q_filt = q_temp[i];
1651  }
1652 
1653  sbr->dsp.hf_g_filt(Y1[i] + kx, X_high + kx, g_filt, m_max,
1654  i + ENVELOPE_ADJUSTMENT_OFFSET);
1655 
1656  if (e != e_a[0] && e != e_a[1]) {
1657  sbr->dsp.hf_apply_noise[indexsine](Y1[i] + kx, sbr->s_m[e],
1658  q_filt, indexnoise,
1659  kx, m_max);
1660  } else {
1661  int idx = indexsine&1;
1662  int A = (1-((indexsine+(kx & 1))&2));
1663  int B = (A^(-idx)) + idx;
1664  float *out = &Y1[i][kx][idx];
1665  float *in = sbr->s_m[e];
1666  for (m = 0; m+1 < m_max; m+=2) {
1667  out[2*m ] += in[m ] * A;
1668  out[2*m+2] += in[m+1] * B;
1669  }
1670  if(m_max&1)
1671  out[2*m ] += in[m ] * A;
1672  }
1673  indexnoise = (indexnoise + m_max) & 0x1ff;
1674  indexsine = (indexsine + 1) & 3;
1675  }
1676  }
1677  ch_data->f_indexnoise = indexnoise;
1678  ch_data->f_indexsine = indexsine;
1679 }
1680 
1681 void ff_sbr_apply(AACContext *ac, SpectralBandReplication *sbr, int id_aac,
1682  float* L, float* R)
1683 {
1684  int downsampled = ac->oc[1].m4ac.ext_sample_rate < sbr->sample_rate;
1685  int ch;
1686  int nch = (id_aac == TYPE_CPE) ? 2 : 1;
1687  int err;
1688 
1689  if (!sbr->kx_and_m_pushed) {
1690  sbr->kx[0] = sbr->kx[1];
1691  sbr->m[0] = sbr->m[1];
1692  } else {
1693  sbr->kx_and_m_pushed = 0;
1694  }
1695 
1696  if (sbr->start) {
1697  sbr_dequant(sbr, id_aac);
1698  }
1699  for (ch = 0; ch < nch; ch++) {
1700  /* decode channel */
1701  sbr_qmf_analysis(&ac->fdsp, &sbr->mdct_ana, &sbr->dsp, ch ? R : L, sbr->data[ch].analysis_filterbank_samples,
1702  (float*)sbr->qmf_filter_scratch,
1703  sbr->data[ch].W, sbr->data[ch].Ypos);
1704  sbr->c.sbr_lf_gen(ac, sbr, sbr->X_low, sbr->data[ch].W, sbr->data[ch].Ypos);
1705  sbr->data[ch].Ypos ^= 1;
1706  if (sbr->start) {
1707  sbr->c.sbr_hf_inverse_filter(&sbr->dsp, sbr->alpha0, sbr->alpha1, sbr->X_low, sbr->k[0]);
1708  sbr_chirp(sbr, &sbr->data[ch]);
1709  sbr_hf_gen(ac, sbr, sbr->X_high, sbr->X_low, sbr->alpha0, sbr->alpha1,
1710  sbr->data[ch].bw_array, sbr->data[ch].t_env,
1711  sbr->data[ch].bs_num_env);
1712 
1713  // hf_adj
1714  err = sbr_mapping(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1715  if (!err) {
1716  sbr_env_estimate(sbr->e_curr, sbr->X_high, sbr, &sbr->data[ch]);
1717  sbr_gain_calc(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1718  sbr->c.sbr_hf_assemble(sbr->data[ch].Y[sbr->data[ch].Ypos],
1719  sbr->X_high, sbr, &sbr->data[ch],
1720  sbr->data[ch].e_a);
1721  }
1722  }
1723 
1724  /* synthesis */
1725  sbr->c.sbr_x_gen(sbr, sbr->X[ch],
1726  sbr->data[ch].Y[1-sbr->data[ch].Ypos],
1727  sbr->data[ch].Y[ sbr->data[ch].Ypos],
1728  sbr->X_low, ch);
1729  }
1730 
1731  if (ac->oc[1].m4ac.ps == 1) {
1732  if (sbr->ps.start) {
1733  ff_ps_apply(ac->avctx, &sbr->ps, sbr->X[0], sbr->X[1], sbr->kx[1] + sbr->m[1]);
1734  } else {
1735  memcpy(sbr->X[1], sbr->X[0], sizeof(sbr->X[0]));
1736  }
1737  nch = 2;
1738  }
1739 
1740  sbr_qmf_synthesis(&sbr->mdct, &sbr->dsp, &ac->fdsp,
1741  L, sbr->X[0], sbr->qmf_filter_scratch,
1742  sbr->data[0].synthesis_filterbank_samples,
1743  &sbr->data[0].synthesis_filterbank_samples_offset,
1744  downsampled);
1745  if (nch == 2)
1746  sbr_qmf_synthesis(&sbr->mdct, &sbr->dsp, &ac->fdsp,
1747  R, sbr->X[1], sbr->qmf_filter_scratch,
1748  sbr->data[1].synthesis_filterbank_samples,
1749  &sbr->data[1].synthesis_filterbank_samples_offset,
1750  downsampled);
1751 }
1752 
1753 static void aacsbr_func_ptr_init(AACSBRContext *c)
1754 {
1755  c->sbr_lf_gen = sbr_lf_gen;
1756  c->sbr_hf_assemble = sbr_hf_assemble;
1757  c->sbr_x_gen = sbr_x_gen;
1758  c->sbr_hf_inverse_filter = sbr_hf_inverse_filter;
1759 
1760  if(ARCH_MIPS)
1761  ff_aacsbr_func_ptr_init_mips(c);
1762 }
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