FFmpeg
aaccoder.c
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1 /*
2  * AAC coefficients encoder
3  * Copyright (C) 2008-2009 Konstantin Shishkov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * AAC coefficients encoder
25  */
26 
27 /***********************************
28  * TODOs:
29  * speedup quantizer selection
30  * add sane pulse detection
31  ***********************************/
32 
33 #include "libavutil/libm.h" // brought forward to work around cygwin header breakage
34 
35 #include <float.h>
36 
37 #include "libavutil/mathematics.h"
38 #include "mathops.h"
39 #include "avcodec.h"
40 #include "put_bits.h"
41 #include "aac.h"
42 #include "aacenc.h"
43 #include "aactab.h"
44 #include "aacenctab.h"
45 #include "aacenc_utils.h"
46 #include "aacenc_quantization.h"
47 
48 #include "aacenc_is.h"
49 #include "aacenc_tns.h"
50 #include "aacenc_ltp.h"
51 #include "aacenc_pred.h"
52 
53 #include "libavcodec/aaccoder_twoloop.h"
54 
55 /* Parameter of f(x) = a*(lambda/100), defines the maximum fourier spread
56  * beyond which no PNS is used (since the SFBs contain tone rather than noise) */
57 #define NOISE_SPREAD_THRESHOLD 0.9f
58 
59 /* Parameter of f(x) = a*(100/lambda), defines how much PNS is allowed to
60  * replace low energy non zero bands */
61 #define NOISE_LAMBDA_REPLACE 1.948f
62 
63 #include "libavcodec/aaccoder_trellis.h"
64 
65 /**
66  * structure used in optimal codebook search
67  */
68 typedef struct BandCodingPath {
69  int prev_idx; ///< pointer to the previous path point
70  float cost; ///< path cost
71  int run;
72 } BandCodingPath;
73 
74 /**
75  * Encode band info for single window group bands.
76  */
77 static void encode_window_bands_info(AACEncContext *s, SingleChannelElement *sce,
78  int win, int group_len, const float lambda)
79 {
80  BandCodingPath path[120][CB_TOT_ALL];
81  int w, swb, cb, start, size;
82  int i, j;
83  const int max_sfb = sce->ics.max_sfb;
84  const int run_bits = sce->ics.num_windows == 1 ? 5 : 3;
85  const int run_esc = (1 << run_bits) - 1;
86  int idx, ppos, count;
87  int stackrun[120], stackcb[120], stack_len;
88  float next_minrd = INFINITY;
89  int next_mincb = 0;
90 
91  s->abs_pow34(s->scoefs, sce->coeffs, 1024);
92  start = win*128;
93  for (cb = 0; cb < CB_TOT_ALL; cb++) {
94  path[0][cb].cost = 0.0f;
95  path[0][cb].prev_idx = -1;
96  path[0][cb].run = 0;
97  }
98  for (swb = 0; swb < max_sfb; swb++) {
99  size = sce->ics.swb_sizes[swb];
100  if (sce->zeroes[win*16 + swb]) {
101  for (cb = 0; cb < CB_TOT_ALL; cb++) {
102  path[swb+1][cb].prev_idx = cb;
103  path[swb+1][cb].cost = path[swb][cb].cost;
104  path[swb+1][cb].run = path[swb][cb].run + 1;
105  }
106  } else {
107  float minrd = next_minrd;
108  int mincb = next_mincb;
109  next_minrd = INFINITY;
110  next_mincb = 0;
111  for (cb = 0; cb < CB_TOT_ALL; cb++) {
112  float cost_stay_here, cost_get_here;
113  float rd = 0.0f;
114  if (cb >= 12 && sce->band_type[win*16+swb] < aac_cb_out_map[cb] ||
115  cb < aac_cb_in_map[sce->band_type[win*16+swb]] && sce->band_type[win*16+swb] > aac_cb_out_map[cb]) {
116  path[swb+1][cb].prev_idx = -1;
117  path[swb+1][cb].cost = INFINITY;
118  path[swb+1][cb].run = path[swb][cb].run + 1;
119  continue;
120  }
121  for (w = 0; w < group_len; w++) {
122  FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(win+w)*16+swb];
123  rd += quantize_band_cost(s, &sce->coeffs[start + w*128],
124  &s->scoefs[start + w*128], size,
125  sce->sf_idx[(win+w)*16+swb], aac_cb_out_map[cb],
126  lambda / band->threshold, INFINITY, NULL, NULL, 0);
127  }
128  cost_stay_here = path[swb][cb].cost + rd;
129  cost_get_here = minrd + rd + run_bits + 4;
130  if ( run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run]
131  != run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1])
132  cost_stay_here += run_bits;
133  if (cost_get_here < cost_stay_here) {
134  path[swb+1][cb].prev_idx = mincb;
135  path[swb+1][cb].cost = cost_get_here;
136  path[swb+1][cb].run = 1;
137  } else {
138  path[swb+1][cb].prev_idx = cb;
139  path[swb+1][cb].cost = cost_stay_here;
140  path[swb+1][cb].run = path[swb][cb].run + 1;
141  }
142  if (path[swb+1][cb].cost < next_minrd) {
143  next_minrd = path[swb+1][cb].cost;
144  next_mincb = cb;
145  }
146  }
147  }
148  start += sce->ics.swb_sizes[swb];
149  }
150 
151  //convert resulting path from backward-linked list
152  stack_len = 0;
153  idx = 0;
154  for (cb = 1; cb < CB_TOT_ALL; cb++)
155  if (path[max_sfb][cb].cost < path[max_sfb][idx].cost)
156  idx = cb;
157  ppos = max_sfb;
158  while (ppos > 0) {
159  av_assert1(idx >= 0);
160  cb = idx;
161  stackrun[stack_len] = path[ppos][cb].run;
162  stackcb [stack_len] = cb;
163  idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx;
164  ppos -= path[ppos][cb].run;
165  stack_len++;
166  }
167  //perform actual band info encoding
168  start = 0;
169  for (i = stack_len - 1; i >= 0; i--) {
170  cb = aac_cb_out_map[stackcb[i]];
171  put_bits(&s->pb, 4, cb);
172  count = stackrun[i];
173  memset(sce->zeroes + win*16 + start, !cb, count);
174  //XXX: memset when band_type is also uint8_t
175  for (j = 0; j < count; j++) {
176  sce->band_type[win*16 + start] = cb;
177  start++;
178  }
179  while (count >= run_esc) {
180  put_bits(&s->pb, run_bits, run_esc);
181  count -= run_esc;
182  }
183  put_bits(&s->pb, run_bits, count);
184  }
185 }
186 
187 
188 typedef struct TrellisPath {
189  float cost;
190  int prev;
191 } TrellisPath;
192 
193 #define TRELLIS_STAGES 121
194 #define TRELLIS_STATES (SCALE_MAX_DIFF+1)
195 
196 static void set_special_band_scalefactors(AACEncContext *s, SingleChannelElement *sce)
197 {
198  int w, g;
199  int prevscaler_n = -255, prevscaler_i = 0;
200  int bands = 0;
201 
202  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
203  for (g = 0; g < sce->ics.num_swb; g++) {
204  if (sce->zeroes[w*16+g])
205  continue;
206  if (sce->band_type[w*16+g] == INTENSITY_BT || sce->band_type[w*16+g] == INTENSITY_BT2) {
207  sce->sf_idx[w*16+g] = av_clip(roundf(log2f(sce->is_ener[w*16+g])*2), -155, 100);
208  bands++;
209  } else if (sce->band_type[w*16+g] == NOISE_BT) {
210  sce->sf_idx[w*16+g] = av_clip(3+ceilf(log2f(sce->pns_ener[w*16+g])*2), -100, 155);
211  if (prevscaler_n == -255)
212  prevscaler_n = sce->sf_idx[w*16+g];
213  bands++;
214  }
215  }
216  }
217 
218  if (!bands)
219  return;
220 
221  /* Clip the scalefactor indices */
222  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
223  for (g = 0; g < sce->ics.num_swb; g++) {
224  if (sce->zeroes[w*16+g])
225  continue;
226  if (sce->band_type[w*16+g] == INTENSITY_BT || sce->band_type[w*16+g] == INTENSITY_BT2) {
227  sce->sf_idx[w*16+g] = prevscaler_i = av_clip(sce->sf_idx[w*16+g], prevscaler_i - SCALE_MAX_DIFF, prevscaler_i + SCALE_MAX_DIFF);
228  } else if (sce->band_type[w*16+g] == NOISE_BT) {
229  sce->sf_idx[w*16+g] = prevscaler_n = av_clip(sce->sf_idx[w*16+g], prevscaler_n - SCALE_MAX_DIFF, prevscaler_n + SCALE_MAX_DIFF);
230  }
231  }
232  }
233 }
234 
235 static void search_for_quantizers_anmr(AVCodecContext *avctx, AACEncContext *s,
236  SingleChannelElement *sce,
237  const float lambda)
238 {
239  int q, w, w2, g, start = 0;
240  int i, j;
241  int idx;
242  TrellisPath paths[TRELLIS_STAGES][TRELLIS_STATES];
243  int bandaddr[TRELLIS_STAGES];
244  int minq;
245  float mincost;
246  float q0f = FLT_MAX, q1f = 0.0f, qnrgf = 0.0f;
247  int q0, q1, qcnt = 0;
248 
249  for (i = 0; i < 1024; i++) {
250  float t = fabsf(sce->coeffs[i]);
251  if (t > 0.0f) {
252  q0f = FFMIN(q0f, t);
253  q1f = FFMAX(q1f, t);
254  qnrgf += t*t;
255  qcnt++;
256  }
257  }
258 
259  if (!qcnt) {
260  memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
261  memset(sce->zeroes, 1, sizeof(sce->zeroes));
262  return;
263  }
264 
265  //minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped
266  q0 = av_clip(coef2minsf(q0f), 0, SCALE_MAX_POS-1);
267  //maximum scalefactor index is when maximum coefficient after quantizing is still not zero
268  q1 = av_clip(coef2maxsf(q1f), 1, SCALE_MAX_POS);
269  if (q1 - q0 > 60) {
270  int q0low = q0;
271  int q1high = q1;
272  //minimum scalefactor index is when maximum nonzero coefficient after quantizing is not clipped
273  int qnrg = av_clip_uint8(log2f(sqrtf(qnrgf/qcnt))*4 - 31 + SCALE_ONE_POS - SCALE_DIV_512);
274  q1 = qnrg + 30;
275  q0 = qnrg - 30;
276  if (q0 < q0low) {
277  q1 += q0low - q0;
278  q0 = q0low;
279  } else if (q1 > q1high) {
280  q0 -= q1 - q1high;
281  q1 = q1high;
282  }
283  }
284  // q0 == q1 isn't really a legal situation
285  if (q0 == q1) {
286  // the following is indirect but guarantees q1 != q0 && q1 near q0
287  q1 = av_clip(q0+1, 1, SCALE_MAX_POS);
288  q0 = av_clip(q1-1, 0, SCALE_MAX_POS - 1);
289  }
290 
291  for (i = 0; i < TRELLIS_STATES; i++) {
292  paths[0][i].cost = 0.0f;
293  paths[0][i].prev = -1;
294  }
295  for (j = 1; j < TRELLIS_STAGES; j++) {
296  for (i = 0; i < TRELLIS_STATES; i++) {
297  paths[j][i].cost = INFINITY;
298  paths[j][i].prev = -2;
299  }
300  }
301  idx = 1;
302  s->abs_pow34(s->scoefs, sce->coeffs, 1024);
303  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
304  start = w*128;
305  for (g = 0; g < sce->ics.num_swb; g++) {
306  const float *coefs = &sce->coeffs[start];
307  float qmin, qmax;
308  int nz = 0;
309 
310  bandaddr[idx] = w * 16 + g;
311  qmin = INT_MAX;
312  qmax = 0.0f;
313  for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
314  FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
315  if (band->energy <= band->threshold || band->threshold == 0.0f) {
316  sce->zeroes[(w+w2)*16+g] = 1;
317  continue;
318  }
319  sce->zeroes[(w+w2)*16+g] = 0;
320  nz = 1;
321  for (i = 0; i < sce->ics.swb_sizes[g]; i++) {
322  float t = fabsf(coefs[w2*128+i]);
323  if (t > 0.0f)
324  qmin = FFMIN(qmin, t);
325  qmax = FFMAX(qmax, t);
326  }
327  }
328  if (nz) {
329  int minscale, maxscale;
330  float minrd = INFINITY;
331  float maxval;
332  //minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped
333  minscale = coef2minsf(qmin);
334  //maximum scalefactor index is when maximum coefficient after quantizing is still not zero
335  maxscale = coef2maxsf(qmax);
336  minscale = av_clip(minscale - q0, 0, TRELLIS_STATES - 1);
337  maxscale = av_clip(maxscale - q0, 0, TRELLIS_STATES);
338  if (minscale == maxscale) {
339  maxscale = av_clip(minscale+1, 1, TRELLIS_STATES);
340  minscale = av_clip(maxscale-1, 0, TRELLIS_STATES - 1);
341  }
342  maxval = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], s->scoefs+start);
343  for (q = minscale; q < maxscale; q++) {
344  float dist = 0;
345  int cb = find_min_book(maxval, sce->sf_idx[w*16+g]);
346  for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
347  FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
348  dist += quantize_band_cost(s, coefs + w2*128, s->scoefs + start + w2*128, sce->ics.swb_sizes[g],
349  q + q0, cb, lambda / band->threshold, INFINITY, NULL, NULL, 0);
350  }
351  minrd = FFMIN(minrd, dist);
352 
353  for (i = 0; i < q1 - q0; i++) {
354  float cost;
355  cost = paths[idx - 1][i].cost + dist
356  + ff_aac_scalefactor_bits[q - i + SCALE_DIFF_ZERO];
357  if (cost < paths[idx][q].cost) {
358  paths[idx][q].cost = cost;
359  paths[idx][q].prev = i;
360  }
361  }
362  }
363  } else {
364  for (q = 0; q < q1 - q0; q++) {
365  paths[idx][q].cost = paths[idx - 1][q].cost + 1;
366  paths[idx][q].prev = q;
367  }
368  }
369  sce->zeroes[w*16+g] = !nz;
370  start += sce->ics.swb_sizes[g];
371  idx++;
372  }
373  }
374  idx--;
375  mincost = paths[idx][0].cost;
376  minq = 0;
377  for (i = 1; i < TRELLIS_STATES; i++) {
378  if (paths[idx][i].cost < mincost) {
379  mincost = paths[idx][i].cost;
380  minq = i;
381  }
382  }
383  while (idx) {
384  sce->sf_idx[bandaddr[idx]] = minq + q0;
385  minq = FFMAX(paths[idx][minq].prev, 0);
386  idx--;
387  }
388  //set the same quantizers inside window groups
389  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
390  for (g = 0; g < sce->ics.num_swb; g++)
391  for (w2 = 1; w2 < sce->ics.group_len[w]; w2++)
392  sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g];
393 }
394 
395 static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s,
396  SingleChannelElement *sce,
397  const float lambda)
398 {
399  int start = 0, i, w, w2, g;
400  int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->channels * (lambda / 120.f);
401  float dists[128] = { 0 }, uplims[128] = { 0 };
402  float maxvals[128];
403  int fflag, minscaler;
404  int its = 0;
405  int allz = 0;
406  float minthr = INFINITY;
407 
408  // for values above this the decoder might end up in an endless loop
409  // due to always having more bits than what can be encoded.
410  destbits = FFMIN(destbits, 5800);
411  //some heuristic to determine initial quantizers will reduce search time
412  //determine zero bands and upper limits
413  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
414  start = 0;
415  for (g = 0; g < sce->ics.num_swb; g++) {
416  int nz = 0;
417  float uplim = 0.0f, energy = 0.0f;
418  for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
419  FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
420  uplim += band->threshold;
421  energy += band->energy;
422  if (band->energy <= band->threshold || band->threshold == 0.0f) {
423  sce->zeroes[(w+w2)*16+g] = 1;
424  continue;
425  }
426  nz = 1;
427  }
428  uplims[w*16+g] = uplim *512;
429  sce->band_type[w*16+g] = 0;
430  sce->zeroes[w*16+g] = !nz;
431  if (nz)
432  minthr = FFMIN(minthr, uplim);
433  allz |= nz;
434  start += sce->ics.swb_sizes[g];
435  }
436  }
437  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
438  for (g = 0; g < sce->ics.num_swb; g++) {
439  if (sce->zeroes[w*16+g]) {
440  sce->sf_idx[w*16+g] = SCALE_ONE_POS;
441  continue;
442  }
443  sce->sf_idx[w*16+g] = SCALE_ONE_POS + FFMIN(log2f(uplims[w*16+g]/minthr)*4,59);
444  }
445  }
446 
447  if (!allz)
448  return;
449  s->abs_pow34(s->scoefs, sce->coeffs, 1024);
450  ff_quantize_band_cost_cache_init(s);
451 
452  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
453  start = w*128;
454  for (g = 0; g < sce->ics.num_swb; g++) {
455  const float *scaled = s->scoefs + start;
456  maxvals[w*16+g] = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], scaled);
457  start += sce->ics.swb_sizes[g];
458  }
459  }
460 
461  //perform two-loop search
462  //outer loop - improve quality
463  do {
464  int tbits, qstep;
465  minscaler = sce->sf_idx[0];
466  //inner loop - quantize spectrum to fit into given number of bits
467  qstep = its ? 1 : 32;
468  do {
469  int prev = -1;
470  tbits = 0;
471  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
472  start = w*128;
473  for (g = 0; g < sce->ics.num_swb; g++) {
474  const float *coefs = sce->coeffs + start;
475  const float *scaled = s->scoefs + start;
476  int bits = 0;
477  int cb;
478  float dist = 0.0f;
479 
480  if (sce->zeroes[w*16+g] || sce->sf_idx[w*16+g] >= 218) {
481  start += sce->ics.swb_sizes[g];
482  continue;
483  }
484  minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]);
485  cb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]);
486  for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
487  int b;
488  dist += quantize_band_cost_cached(s, w + w2, g,
489  coefs + w2*128,
490  scaled + w2*128,
491  sce->ics.swb_sizes[g],
492  sce->sf_idx[w*16+g],
493  cb, 1.0f, INFINITY,
494  &b, NULL, 0);
495  bits += b;
496  }
497  dists[w*16+g] = dist - bits;
498  if (prev != -1) {
499  bits += ff_aac_scalefactor_bits[sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO];
500  }
501  tbits += bits;
502  start += sce->ics.swb_sizes[g];
503  prev = sce->sf_idx[w*16+g];
504  }
505  }
506  if (tbits > destbits) {
507  for (i = 0; i < 128; i++)
508  if (sce->sf_idx[i] < 218 - qstep)
509  sce->sf_idx[i] += qstep;
510  } else {
511  for (i = 0; i < 128; i++)
512  if (sce->sf_idx[i] > 60 - qstep)
513  sce->sf_idx[i] -= qstep;
514  }
515  qstep >>= 1;
516  if (!qstep && tbits > destbits*1.02 && sce->sf_idx[0] < 217)
517  qstep = 1;
518  } while (qstep);
519 
520  fflag = 0;
521  minscaler = av_clip(minscaler, 60, 255 - SCALE_MAX_DIFF);
522 
523  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
524  for (g = 0; g < sce->ics.num_swb; g++) {
525  int prevsc = sce->sf_idx[w*16+g];
526  if (dists[w*16+g] > uplims[w*16+g] && sce->sf_idx[w*16+g] > 60) {
527  if (find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]-1))
528  sce->sf_idx[w*16+g]--;
529  else //Try to make sure there is some energy in every band
530  sce->sf_idx[w*16+g]-=2;
531  }
532  sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], minscaler, minscaler + SCALE_MAX_DIFF);
533  sce->sf_idx[w*16+g] = FFMIN(sce->sf_idx[w*16+g], 219);
534  if (sce->sf_idx[w*16+g] != prevsc)
535  fflag = 1;
536  sce->band_type[w*16+g] = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]);
537  }
538  }
539  its++;
540  } while (fflag && its < 10);
541 }
542 
543 static void search_for_pns(AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce)
544 {
545  FFPsyBand *band;
546  int w, g, w2, i;
547  int wlen = 1024 / sce->ics.num_windows;
548  int bandwidth, cutoff;
549  float *PNS = &s->scoefs[0*128], *PNS34 = &s->scoefs[1*128];
550  float *NOR34 = &s->scoefs[3*128];
551  uint8_t nextband[128];
552  const float lambda = s->lambda;
553  const float freq_mult = avctx->sample_rate*0.5f/wlen;
554  const float thr_mult = NOISE_LAMBDA_REPLACE*(100.0f/lambda);
555  const float spread_threshold = FFMIN(0.75f, NOISE_SPREAD_THRESHOLD*FFMAX(0.5f, lambda/100.f));
556  const float dist_bias = av_clipf(4.f * 120 / lambda, 0.25f, 4.0f);
557  const float pns_transient_energy_r = FFMIN(0.7f, lambda / 140.f);
558 
559  int refbits = avctx->bit_rate * 1024.0 / avctx->sample_rate
560  / ((avctx->flags & AV_CODEC_FLAG_QSCALE) ? 2.0f : avctx->channels)
561  * (lambda / 120.f);
562 
563  /** Keep this in sync with twoloop's cutoff selection */
564  float rate_bandwidth_multiplier = 1.5f;
565  int prev = -1000, prev_sf = -1;
566  int frame_bit_rate = (avctx->flags & AV_CODEC_FLAG_QSCALE)
567  ? (refbits * rate_bandwidth_multiplier * avctx->sample_rate / 1024)
568  : (avctx->bit_rate / avctx->channels);
569 
570  frame_bit_rate *= 1.15f;
571 
572  if (avctx->cutoff > 0) {
573  bandwidth = avctx->cutoff;
574  } else {
575  bandwidth = FFMAX(3000, AAC_CUTOFF_FROM_BITRATE(frame_bit_rate, 1, avctx->sample_rate));
576  }
577 
578  cutoff = bandwidth * 2 * wlen / avctx->sample_rate;
579 
580  memcpy(sce->band_alt, sce->band_type, sizeof(sce->band_type));
581  ff_init_nextband_map(sce, nextband);
582  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
583  int wstart = w*128;
584  for (g = 0; g < sce->ics.num_swb; g++) {
585  int noise_sfi;
586  float dist1 = 0.0f, dist2 = 0.0f, noise_amp;
587  float pns_energy = 0.0f, pns_tgt_energy, energy_ratio, dist_thresh;
588  float sfb_energy = 0.0f, threshold = 0.0f, spread = 2.0f;
589  float min_energy = -1.0f, max_energy = 0.0f;
590  const int start = wstart+sce->ics.swb_offset[g];
591  const float freq = (start-wstart)*freq_mult;
592  const float freq_boost = FFMAX(0.88f*freq/NOISE_LOW_LIMIT, 1.0f);
593  if (freq < NOISE_LOW_LIMIT || (start-wstart) >= cutoff) {
594  if (!sce->zeroes[w*16+g])
595  prev_sf = sce->sf_idx[w*16+g];
596  continue;
597  }
598  for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
599  band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
600  sfb_energy += band->energy;
601  spread = FFMIN(spread, band->spread);
602  threshold += band->threshold;
603  if (!w2) {
604  min_energy = max_energy = band->energy;
605  } else {
606  min_energy = FFMIN(min_energy, band->energy);
607  max_energy = FFMAX(max_energy, band->energy);
608  }
609  }
610 
611  /* Ramps down at ~8000Hz and loosens the dist threshold */
612  dist_thresh = av_clipf(2.5f*NOISE_LOW_LIMIT/freq, 0.5f, 2.5f) * dist_bias;
613 
614  /* PNS is acceptable when all of these are true:
615  * 1. high spread energy (noise-like band)
616  * 2. near-threshold energy (high PE means the random nature of PNS content will be noticed)
617  * 3. on short window groups, all windows have similar energy (variations in energy would be destroyed by PNS)
618  *
619  * At this stage, point 2 is relaxed for zeroed bands near the noise threshold (hole avoidance is more important)
620  */
621  if ((!sce->zeroes[w*16+g] && !ff_sfdelta_can_remove_band(sce, nextband, prev_sf, w*16+g)) ||
622  ((sce->zeroes[w*16+g] || !sce->band_alt[w*16+g]) && sfb_energy < threshold*sqrtf(1.0f/freq_boost)) || spread < spread_threshold ||
623  (!sce->zeroes[w*16+g] && sce->band_alt[w*16+g] && sfb_energy > threshold*thr_mult*freq_boost) ||
624  min_energy < pns_transient_energy_r * max_energy ) {
625  sce->pns_ener[w*16+g] = sfb_energy;
626  if (!sce->zeroes[w*16+g])
627  prev_sf = sce->sf_idx[w*16+g];
628  continue;
629  }
630 
631  pns_tgt_energy = sfb_energy*FFMIN(1.0f, spread*spread);
632  noise_sfi = av_clip(roundf(log2f(pns_tgt_energy)*2), -100, 155); /* Quantize */
633  noise_amp = -ff_aac_pow2sf_tab[noise_sfi + POW_SF2_ZERO]; /* Dequantize */
634  if (prev != -1000) {
635  int noise_sfdiff = noise_sfi - prev + SCALE_DIFF_ZERO;
636  if (noise_sfdiff < 0 || noise_sfdiff > 2*SCALE_MAX_DIFF) {
637  if (!sce->zeroes[w*16+g])
638  prev_sf = sce->sf_idx[w*16+g];
639  continue;
640  }
641  }
642  for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
643  float band_energy, scale, pns_senergy;
644  const int start_c = (w+w2)*128+sce->ics.swb_offset[g];
645  band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
646  for (i = 0; i < sce->ics.swb_sizes[g]; i++) {
647  s->random_state = lcg_random(s->random_state);
648  PNS[i] = s->random_state;
649  }
650  band_energy = s->fdsp->scalarproduct_float(PNS, PNS, sce->ics.swb_sizes[g]);
651  scale = noise_amp/sqrtf(band_energy);
652  s->fdsp->vector_fmul_scalar(PNS, PNS, scale, sce->ics.swb_sizes[g]);
653  pns_senergy = s->fdsp->scalarproduct_float(PNS, PNS, sce->ics.swb_sizes[g]);
654  pns_energy += pns_senergy;
655  s->abs_pow34(NOR34, &sce->coeffs[start_c], sce->ics.swb_sizes[g]);
656  s->abs_pow34(PNS34, PNS, sce->ics.swb_sizes[g]);
657  dist1 += quantize_band_cost(s, &sce->coeffs[start_c],
658  NOR34,
659  sce->ics.swb_sizes[g],
660  sce->sf_idx[(w+w2)*16+g],
661  sce->band_alt[(w+w2)*16+g],
662  lambda/band->threshold, INFINITY, NULL, NULL, 0);
663  /* Estimate rd on average as 5 bits for SF, 4 for the CB, plus spread energy * lambda/thr */
664  dist2 += band->energy/(band->spread*band->spread)*lambda*dist_thresh/band->threshold;
665  }
666  if (g && sce->band_type[w*16+g-1] == NOISE_BT) {
667  dist2 += 5;
668  } else {
669  dist2 += 9;
670  }
671  energy_ratio = pns_tgt_energy/pns_energy; /* Compensates for quantization error */
672  sce->pns_ener[w*16+g] = energy_ratio*pns_tgt_energy;
673  if (sce->zeroes[w*16+g] || !sce->band_alt[w*16+g] || (energy_ratio > 0.85f && energy_ratio < 1.25f && dist2 < dist1)) {
674  sce->band_type[w*16+g] = NOISE_BT;
675  sce->zeroes[w*16+g] = 0;
676  prev = noise_sfi;
677  } else {
678  if (!sce->zeroes[w*16+g])
679  prev_sf = sce->sf_idx[w*16+g];
680  }
681  }
682  }
683 }
684 
685 static void mark_pns(AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce)
686 {
687  FFPsyBand *band;
688  int w, g, w2;
689  int wlen = 1024 / sce->ics.num_windows;
690  int bandwidth, cutoff;
691  const float lambda = s->lambda;
692  const float freq_mult = avctx->sample_rate*0.5f/wlen;
693  const float spread_threshold = FFMIN(0.75f, NOISE_SPREAD_THRESHOLD*FFMAX(0.5f, lambda/100.f));
694  const float pns_transient_energy_r = FFMIN(0.7f, lambda / 140.f);
695 
696  int refbits = avctx->bit_rate * 1024.0 / avctx->sample_rate
697  / ((avctx->flags & AV_CODEC_FLAG_QSCALE) ? 2.0f : avctx->channels)
698  * (lambda / 120.f);
699 
700  /** Keep this in sync with twoloop's cutoff selection */
701  float rate_bandwidth_multiplier = 1.5f;
702  int frame_bit_rate = (avctx->flags & AV_CODEC_FLAG_QSCALE)
703  ? (refbits * rate_bandwidth_multiplier * avctx->sample_rate / 1024)
704  : (avctx->bit_rate / avctx->channels);
705 
706  frame_bit_rate *= 1.15f;
707 
708  if (avctx->cutoff > 0) {
709  bandwidth = avctx->cutoff;
710  } else {
711  bandwidth = FFMAX(3000, AAC_CUTOFF_FROM_BITRATE(frame_bit_rate, 1, avctx->sample_rate));
712  }
713 
714  cutoff = bandwidth * 2 * wlen / avctx->sample_rate;
715 
716  memcpy(sce->band_alt, sce->band_type, sizeof(sce->band_type));
717  for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
718  for (g = 0; g < sce->ics.num_swb; g++) {
719  float sfb_energy = 0.0f, threshold = 0.0f, spread = 2.0f;
720  float min_energy = -1.0f, max_energy = 0.0f;
721  const int start = sce->ics.swb_offset[g];
722  const float freq = start*freq_mult;
723  const float freq_boost = FFMAX(0.88f*freq/NOISE_LOW_LIMIT, 1.0f);
724  if (freq < NOISE_LOW_LIMIT || start >= cutoff) {
725  sce->can_pns[w*16+g] = 0;
726  continue;
727  }
728  for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
729  band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
730  sfb_energy += band->energy;
731  spread = FFMIN(spread, band->spread);
732  threshold += band->threshold;
733  if (!w2) {
734  min_energy = max_energy = band->energy;
735  } else {
736  min_energy = FFMIN(min_energy, band->energy);
737  max_energy = FFMAX(max_energy, band->energy);
738  }
739  }
740 
741  /* PNS is acceptable when all of these are true:
742  * 1. high spread energy (noise-like band)
743  * 2. near-threshold energy (high PE means the random nature of PNS content will be noticed)
744  * 3. on short window groups, all windows have similar energy (variations in energy would be destroyed by PNS)
745  */
746  sce->pns_ener[w*16+g] = sfb_energy;
747  if (sfb_energy < threshold*sqrtf(1.5f/freq_boost) || spread < spread_threshold || min_energy < pns_transient_energy_r * max_energy) {
748  sce->can_pns[w*16+g] = 0;
749  } else {
750  sce->can_pns[w*16+g] = 1;
751  }
752  }
753  }
754 }
755 
756 static void search_for_ms(AACEncContext *s, ChannelElement *cpe)
757 {
758  int start = 0, i, w, w2, g, sid_sf_boost, prev_mid, prev_side;
759  uint8_t nextband0[128], nextband1[128];
760  float *M = s->scoefs + 128*0, *S = s->scoefs + 128*1;
761  float *L34 = s->scoefs + 128*2, *R34 = s->scoefs + 128*3;
762  float *M34 = s->scoefs + 128*4, *S34 = s->scoefs + 128*5;
763  const float lambda = s->lambda;
764  const float mslambda = FFMIN(1.0f, lambda / 120.f);
765  SingleChannelElement *sce0 = &cpe->ch[0];
766  SingleChannelElement *sce1 = &cpe->ch[1];
767  if (!cpe->common_window)
768  return;
769 
770  /** Scout out next nonzero bands */
771  ff_init_nextband_map(sce0, nextband0);
772  ff_init_nextband_map(sce1, nextband1);
773 
774  prev_mid = sce0->sf_idx[0];
775  prev_side = sce1->sf_idx[0];
776  for (w = 0; w < sce0->ics.num_windows; w += sce0->ics.group_len[w]) {
777  start = 0;
778  for (g = 0; g < sce0->ics.num_swb; g++) {
779  float bmax = bval2bmax(g * 17.0f / sce0->ics.num_swb) / 0.0045f;
780  if (!cpe->is_mask[w*16+g])
781  cpe->ms_mask[w*16+g] = 0;
782  if (!sce0->zeroes[w*16+g] && !sce1->zeroes[w*16+g] && !cpe->is_mask[w*16+g]) {
783  float Mmax = 0.0f, Smax = 0.0f;
784 
785  /* Must compute mid/side SF and book for the whole window group */
786  for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) {
787  for (i = 0; i < sce0->ics.swb_sizes[g]; i++) {
788  M[i] = (sce0->coeffs[start+(w+w2)*128+i]
789  + sce1->coeffs[start+(w+w2)*128+i]) * 0.5;
790  S[i] = M[i]
791  - sce1->coeffs[start+(w+w2)*128+i];
792  }
793  s->abs_pow34(M34, M, sce0->ics.swb_sizes[g]);
794  s->abs_pow34(S34, S, sce0->ics.swb_sizes[g]);
795  for (i = 0; i < sce0->ics.swb_sizes[g]; i++ ) {
796  Mmax = FFMAX(Mmax, M34[i]);
797  Smax = FFMAX(Smax, S34[i]);
798  }
799  }
800 
801  for (sid_sf_boost = 0; sid_sf_boost < 4; sid_sf_boost++) {
802  float dist1 = 0.0f, dist2 = 0.0f;
803  int B0 = 0, B1 = 0;
804  int minidx;
805  int mididx, sididx;
806  int midcb, sidcb;
807 
808  minidx = FFMIN(sce0->sf_idx[w*16+g], sce1->sf_idx[w*16+g]);
809  mididx = av_clip(minidx, 0, SCALE_MAX_POS - SCALE_DIV_512);
810  sididx = av_clip(minidx - sid_sf_boost * 3, 0, SCALE_MAX_POS - SCALE_DIV_512);
811  if (sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT
812  && ( !ff_sfdelta_can_replace(sce0, nextband0, prev_mid, mididx, w*16+g)
813  || !ff_sfdelta_can_replace(sce1, nextband1, prev_side, sididx, w*16+g))) {
814  /* scalefactor range violation, bad stuff, will decrease quality unacceptably */
815  continue;
816  }
817 
818  midcb = find_min_book(Mmax, mididx);
819  sidcb = find_min_book(Smax, sididx);
820 
821  /* No CB can be zero */
822  midcb = FFMAX(1,midcb);
823  sidcb = FFMAX(1,sidcb);
824 
825  for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) {
826  FFPsyBand *band0 = &s->psy.ch[s->cur_channel+0].psy_bands[(w+w2)*16+g];
827  FFPsyBand *band1 = &s->psy.ch[s->cur_channel+1].psy_bands[(w+w2)*16+g];
828  float minthr = FFMIN(band0->threshold, band1->threshold);
829  int b1,b2,b3,b4;
830  for (i = 0; i < sce0->ics.swb_sizes[g]; i++) {
831  M[i] = (sce0->coeffs[start+(w+w2)*128+i]
832  + sce1->coeffs[start+(w+w2)*128+i]) * 0.5;
833  S[i] = M[i]
834  - sce1->coeffs[start+(w+w2)*128+i];
835  }
836 
837  s->abs_pow34(L34, sce0->coeffs+start+(w+w2)*128, sce0->ics.swb_sizes[g]);
838  s->abs_pow34(R34, sce1->coeffs+start+(w+w2)*128, sce0->ics.swb_sizes[g]);
839  s->abs_pow34(M34, M, sce0->ics.swb_sizes[g]);
840  s->abs_pow34(S34, S, sce0->ics.swb_sizes[g]);
841  dist1 += quantize_band_cost(s, &sce0->coeffs[start + (w+w2)*128],
842  L34,
843  sce0->ics.swb_sizes[g],
844  sce0->sf_idx[w*16+g],
845  sce0->band_type[w*16+g],
846  lambda / (band0->threshold + FLT_MIN), INFINITY, &b1, NULL, 0);
847  dist1 += quantize_band_cost(s, &sce1->coeffs[start + (w+w2)*128],
848  R34,
849  sce1->ics.swb_sizes[g],
850  sce1->sf_idx[w*16+g],
851  sce1->band_type[w*16+g],
852  lambda / (band1->threshold + FLT_MIN), INFINITY, &b2, NULL, 0);
853  dist2 += quantize_band_cost(s, M,
854  M34,
855  sce0->ics.swb_sizes[g],
856  mididx,
857  midcb,
858  lambda / (minthr + FLT_MIN), INFINITY, &b3, NULL, 0);
859  dist2 += quantize_band_cost(s, S,
860  S34,
861  sce1->ics.swb_sizes[g],
862  sididx,
863  sidcb,
864  mslambda / (minthr * bmax + FLT_MIN), INFINITY, &b4, NULL, 0);
865  B0 += b1+b2;
866  B1 += b3+b4;
867  dist1 -= b1+b2;
868  dist2 -= b3+b4;
869  }
870  cpe->ms_mask[w*16+g] = dist2 <= dist1 && B1 < B0;
871  if (cpe->ms_mask[w*16+g]) {
872  if (sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT) {
873  sce0->sf_idx[w*16+g] = mididx;
874  sce1->sf_idx[w*16+g] = sididx;
875  sce0->band_type[w*16+g] = midcb;
876  sce1->band_type[w*16+g] = sidcb;
877  } else if ((sce0->band_type[w*16+g] != NOISE_BT) ^ (sce1->band_type[w*16+g] != NOISE_BT)) {
878  /* ms_mask unneeded, and it confuses some decoders */
879  cpe->ms_mask[w*16+g] = 0;
880  }
881  break;
882  } else if (B1 > B0) {
883  /* More boost won't fix this */
884  break;
885  }
886  }
887  }
888  if (!sce0->zeroes[w*16+g] && sce0->band_type[w*16+g] < RESERVED_BT)
889  prev_mid = sce0->sf_idx[w*16+g];
890  if (!sce1->zeroes[w*16+g] && !cpe->is_mask[w*16+g] && sce1->band_type[w*16+g] < RESERVED_BT)
891  prev_side = sce1->sf_idx[w*16+g];
892  start += sce0->ics.swb_sizes[g];
893  }
894  }
895 }
896 
897 const AACCoefficientsEncoder ff_aac_coders[AAC_CODER_NB] = {
898  [AAC_CODER_ANMR] = {
899  search_for_quantizers_anmr,
900  encode_window_bands_info,
901  quantize_and_encode_band,
902  ff_aac_encode_tns_info,
903  ff_aac_encode_ltp_info,
904  ff_aac_encode_main_pred,
905  ff_aac_adjust_common_pred,
906  ff_aac_adjust_common_ltp,
907  ff_aac_apply_main_pred,
908  ff_aac_apply_tns,
909  ff_aac_update_ltp,
910  ff_aac_ltp_insert_new_frame,
911  set_special_band_scalefactors,
912  search_for_pns,
913  mark_pns,
914  ff_aac_search_for_tns,
915  ff_aac_search_for_ltp,
916  search_for_ms,
917  ff_aac_search_for_is,
918  ff_aac_search_for_pred,
919  },
920  [AAC_CODER_TWOLOOP] = {
921  search_for_quantizers_twoloop,
922  codebook_trellis_rate,
923  quantize_and_encode_band,
924  ff_aac_encode_tns_info,
925  ff_aac_encode_ltp_info,
926  ff_aac_encode_main_pred,
927  ff_aac_adjust_common_pred,
928  ff_aac_adjust_common_ltp,
929  ff_aac_apply_main_pred,
930  ff_aac_apply_tns,
931  ff_aac_update_ltp,
932  ff_aac_ltp_insert_new_frame,
933  set_special_band_scalefactors,
934  search_for_pns,
935  mark_pns,
936  ff_aac_search_for_tns,
937  ff_aac_search_for_ltp,
938  search_for_ms,
939  ff_aac_search_for_is,
940  ff_aac_search_for_pred,
941  },
942  [AAC_CODER_FAST] = {
943  search_for_quantizers_fast,
944  codebook_trellis_rate,
945  quantize_and_encode_band,
946  ff_aac_encode_tns_info,
947  ff_aac_encode_ltp_info,
948  ff_aac_encode_main_pred,
949  ff_aac_adjust_common_pred,
950  ff_aac_adjust_common_ltp,
951  ff_aac_apply_main_pred,
952  ff_aac_apply_tns,
953  ff_aac_update_ltp,
954  ff_aac_ltp_insert_new_frame,
955  set_special_band_scalefactors,
956  search_for_pns,
957  mark_pns,
958  ff_aac_search_for_tns,
959  ff_aac_search_for_ltp,
960  search_for_ms,
961  ff_aac_search_for_is,
962  ff_aac_search_for_pred,
963  },
964 };
M
#define M(a, b)
Definition: vp3dsp.c:45
SingleChannelElement::band_alt
enum BandType band_alt[128]
alternative band type (used by encoder)
Definition: aac.h:253
q1
static const uint8_t q1[256]
Definition: twofish.c:96
lcg_random
static av_always_inline int lcg_random(unsigned previous_val)
linear congruential pseudorandom number generator
Definition: aacdec_template.c:1063
INFINITY
#define INFINITY
Definition: mathematics.h:67
SingleChannelElement::can_pns
uint8_t can_pns[128]
band is allowed to PNS (informative)
Definition: aac.h:258
libm.h
B1
#define B1
Definition: faandct.c:41
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:2225
cb
static double cb(void *priv, double x, double y)
Definition: vf_geq.c:112
aacenctab.h
log2f
#define log2f(x)
Definition: libm.h:409
CB_TOT_ALL
#define CB_TOT_ALL
Total number of codebooks, including special ones.
Definition: aacenctab.h:37
ff_aac_update_ltp
void ff_aac_update_ltp(AACEncContext *s, SingleChannelElement *sce)
Process LTP parameters.
Definition: aacenc_ltp.c:117
AV_CODEC_FLAG_QSCALE
#define AV_CODEC_FLAG_QSCALE
Use fixed qscale.
Definition: avcodec.h:850
SingleChannelElement::zeroes
uint8_t zeroes[128]
band is not coded (used by encoder)
Definition: aac.h:257
count
void INT64 INT64 count
Definition: avisynth_c.h:767
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:208
aacenc_ltp.h
w
uint8_t w
Definition: llviddspenc.c:38
bval2bmax
static av_always_inline float bval2bmax(float b)
approximates exp10f(-3.0f*(0.5f + 0.5f * cosf(FFMIN(b,15.5f) / 15.5f)))
Definition: aacenc_utils.h:188
ff_aac_coders
const AACCoefficientsEncoder ff_aac_coders[AAC_CODER_NB]
Definition: aaccoder.c:897
B0
#define B0
Definition: faandct.c:40
b
#define b
Definition: input.c:41
float.h
AAC_CODER_NB
@ AAC_CODER_NB
Definition: aacenc.h:40
mathematics.h
ff_sfdelta_can_remove_band
static int ff_sfdelta_can_remove_band(const SingleChannelElement *sce, const uint8_t *nextband, int prev_sf, int band)
Definition: aacenc_utils.h:232
search_for_ms
static void search_for_ms(AACEncContext *s, ChannelElement *cpe)
Definition: aaccoder.c:756
roundf
static av_always_inline av_const float roundf(float x)
Definition: libm.h:451
coef2maxsf
static uint8_t coef2maxsf(float coef)
Return the maximum scalefactor where the quantized coef is not zero.
Definition: aacenc_utils.h:163
SCALE_MAX_POS
#define SCALE_MAX_POS
scalefactor index maximum value
Definition: aac.h:150
AAC_CODER_FAST
@ AAC_CODER_FAST
Definition: aacenc.h:38
win
static float win(SuperEqualizerContext *s, float n, int N)
Definition: af_superequalizer.c:119
S
#define S(s, c, i)
Definition: flacdsp_template.c:46
IndividualChannelStream::num_swb
int num_swb
number of scalefactor window bands
Definition: aac.h:183
SCALE_DIV_512
#define SCALE_DIV_512
scalefactor difference that corresponds to scale difference in 512 times
Definition: aac.h:148
start
void INT64 start
Definition: avisynth_c.h:767
ff_sfdelta_can_replace
static int ff_sfdelta_can_replace(const SingleChannelElement *sce, const uint8_t *nextband, int prev_sf, int new_sf, int band)
Definition: aacenc_utils.h:246
AVCodecContext::flags
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1645
POW_SF2_ZERO
#define POW_SF2_ZERO
ff_aac_pow2sf_tab index corresponding to pow(2, 0);
Definition: aac.h:154
SingleChannelElement::ics
IndividualChannelStream ics
Definition: aac.h:249
search_for_pns
static void search_for_pns(AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce)
Definition: aaccoder.c:543
NOISE_BT
@ NOISE_BT
Spectral data are scaled white noise not coded in the bitstream.
Definition: aac.h:87
s
#define s(width, name)
Definition: cbs_vp9.c:257
SingleChannelElement::coeffs
INTFLOAT coeffs[1024]
coefficients for IMDCT, maybe processed
Definition: aac.h:262
ff_aac_apply_main_pred
void ff_aac_apply_main_pred(AACEncContext *s, SingleChannelElement *sce)
Definition: aacenc_pred.c:119
IndividualChannelStream::swb_sizes
const uint8_t * swb_sizes
table of scalefactor band sizes for a particular window
Definition: aac.h:182
g
const char * g
Definition: vf_curves.c:115
INTENSITY_BT2
@ INTENSITY_BT2
Scalefactor data are intensity stereo positions (out of phase).
Definition: aac.h:88
bits
uint8_t bits
Definition: vp3data.h:202
IndividualChannelStream::group_len
uint8_t group_len[8]
Definition: aac.h:179
search_for_quantizers_fast
static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s, SingleChannelElement *sce, const float lambda)
Definition: aaccoder.c:395
ff_aac_encode_ltp_info
void ff_aac_encode_ltp_info(AACEncContext *s, SingleChannelElement *sce, int common_window)
Encode LTP data.
Definition: aacenc_ltp.c:35
mark_pns
static void mark_pns(AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce)
Definition: aaccoder.c:685
bands
static const float bands[]
Definition: af_superequalizer.c:56
SCALE_DIFF_ZERO
#define SCALE_DIFF_ZERO
codebook index corresponding to zero scalefactor indices difference
Definition: aac.h:152
f
#define f(width, name)
Definition: cbs_vp9.c:255
IndividualChannelStream::swb_offset
const uint16_t * swb_offset
table of offsets to the lowest spectral coefficient of a scalefactor band, sfb, for a particular wind...
Definition: aac.h:181
q0
static const uint8_t q0[256]
Definition: twofish.c:77
quantize_band_cost_cached
static float quantize_band_cost_cached(struct AACEncContext *s, int w, int g, const float *in, const float *scaled, int size, int scale_idx, int cb, const float lambda, const float uplim, int *bits, float *energy, int rtz)
Definition: aacenc_quantization_misc.h:31
TrellisPath
Definition: aaccoder.c:188
INTENSITY_BT
@ INTENSITY_BT
Scalefactor data are intensity stereo positions (in phase).
Definition: aac.h:89
ChannelElement::is_mask
uint8_t is_mask[128]
Set if intensity stereo is used (used by encoder)
Definition: aac.h:282
NULL
#define NULL
Definition: coverity.c:32
SingleChannelElement::is_ener
float is_ener[128]
Intensity stereo pos (used by encoder)
Definition: aac.h:259
aacenc_quantization.h
codebook_trellis_rate
static void codebook_trellis_rate(AACEncContext *s, SingleChannelElement *sce, int win, int group_len, const float lambda)
Definition: aaccoder_trellis.h:59
ff_aac_apply_tns
void ff_aac_apply_tns(AACEncContext *s, SingleChannelElement *sce)
Definition: aacenc_tns.c:102
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1615
mathops.h
FFPsyBand
single band psychoacoustic information
Definition: psymodel.h:50
aac.h
aactab.h
ff_aac_encode_tns_info
void ff_aac_encode_tns_info(AACEncContext *s, SingleChannelElement *sce)
Encode TNS data.
Definition: aacenc_tns.c:70
ff_init_nextband_map
static void ff_init_nextband_map(const SingleChannelElement *sce, uint8_t *nextband)
Definition: aacenc_utils.h:199
aaccoder_twoloop.h
run_value_bits
static const uint8_t *const run_value_bits[2]
Definition: aacenctab.h:116
SingleChannelElement::sf_idx
int sf_idx[128]
scalefactor indices (used by encoder)
Definition: aac.h:256
ff_aac_ltp_insert_new_frame
void ff_aac_ltp_insert_new_frame(AACEncContext *s)
Definition: aacenc_ltp.c:53
ff_aac_scalefactor_bits
const uint8_t ff_aac_scalefactor_bits[121]
Definition: aactab.c:92
coef2minsf
static uint8_t coef2minsf(float coef)
Return the minimum scalefactor where the quantized coef does not clip.
Definition: aacenc_utils.h:157
aac_cb_out_map
static const uint8_t aac_cb_out_map[CB_TOT_ALL]
Map to convert values from BandCodingPath index to a codebook index.
Definition: aacenctab.h:121
AAC_CODER_ANMR
@ AAC_CODER_ANMR
Definition: aacenc.h:36
ChannelElement::ch
SingleChannelElement ch[2]
Definition: aac.h:284
ff_aac_adjust_common_pred
void ff_aac_adjust_common_pred(AACEncContext *s, ChannelElement *cpe)
Definition: aacenc_pred.c:151
FFMAX
#define FFMAX(a, b)
Definition: common.h:94
NOISE_SPREAD_THRESHOLD
#define NOISE_SPREAD_THRESHOLD
Definition: aaccoder.c:57
size
int size
Definition: twinvq_data.h:11134
run_bits
static const uint8_t run_bits[7][16]
Definition: h264_cavlc.c:229
AAC_CODER_TWOLOOP
@ AAC_CODER_TWOLOOP
Definition: aacenc.h:37
ChannelElement::common_window
int common_window
Set if channels share a common 'IndividualChannelStream' in bitstream.
Definition: aac.h:278
FFMIN
#define FFMIN(a, b)
Definition: common.h:96
ff_aac_adjust_common_ltp
void ff_aac_adjust_common_ltp(AACEncContext *s, ChannelElement *cpe)
Definition: aacenc_ltp.c:130
search_for_quantizers_twoloop
static void search_for_quantizers_twoloop(AVCodecContext *avctx, AACEncContext *s, SingleChannelElement *sce, const float lambda)
two-loop quantizers search taken from ISO 13818-7 Appendix C
Definition: aaccoder_twoloop.h:67
ChannelElement::ms_mask
uint8_t ms_mask[128]
Set if mid/side stereo is used for each scalefactor window band.
Definition: aac.h:281
SCALE_MAX_DIFF
#define SCALE_MAX_DIFF
maximum scalefactor difference allowed by standard
Definition: aac.h:151
SingleChannelElement::pns_ener
float pns_ener[128]
Noise energy values (used by encoder)
Definition: aac.h:260
AVCodecContext::channels
int channels
number of audio channels
Definition: avcodec.h:2226
AAC_CUTOFF_FROM_BITRATE
#define AAC_CUTOFF_FROM_BITRATE(bit_rate, channels, sample_rate)
Definition: psymodel.h:35
aacenc_is.h
search_for_quantizers_anmr
static void search_for_quantizers_anmr(AVCodecContext *avctx, AACEncContext *s, SingleChannelElement *sce, const float lambda)
Definition: aaccoder.c:235
SingleChannelElement
Single Channel Element - used for both SCE and LFE elements.
Definition: aac.h:248
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
IndividualChannelStream::num_windows
int num_windows
Definition: aac.h:184
SCALE_ONE_POS
#define SCALE_ONE_POS
scalefactor index that corresponds to scale=1.0
Definition: aac.h:149
find_min_book
static int find_min_book(float maxval, int sf)
Definition: aacenc_utils.h:92
aac_cb_in_map
static const uint8_t aac_cb_in_map[CB_TOT_ALL+1]
Inverse map to convert from codebooks to BandCodingPath indices.
Definition: aacenctab.h:123
FFPsyBand::threshold
float threshold
Definition: psymodel.h:53
ff_aac_search_for_tns
void ff_aac_search_for_tns(AACEncContext *s, SingleChannelElement *sce)
Definition: aacenc_tns.c:161
ChannelElement
channel element - generic struct for SCE/CPE/CCE/LFE
Definition: aac.h:275
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:2269
av_assert1
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
uint8_t
uint8_t
Definition: audio_convert.c:194
TrellisPath::prev
int prev
Definition: aaccoder.c:190
set_special_band_scalefactors
static void set_special_band_scalefactors(AACEncContext *s, SingleChannelElement *sce)
Definition: aaccoder.c:196
NOISE_LOW_LIMIT
#define NOISE_LOW_LIMIT
This file contains a template for the twoloop coder function.
Definition: aaccoder_twoloop.h:54
AACCoefficientsEncoder
Definition: aacenc.h:56
ff_aac_search_for_is
void ff_aac_search_for_is(AACEncContext *s, AVCodecContext *avctx, ChannelElement *cpe)
Definition: aacenc_is.c:98
avcodec.h
TRELLIS_STAGES
#define TRELLIS_STAGES
Definition: aaccoder.c:193
BandCodingPath
structure used in optimal codebook search
Definition: aaccoder.c:68
RESERVED_BT
@ RESERVED_BT
Band types following are encoded differently from others.
Definition: aac.h:86
AACEncContext
AAC encoder context.
Definition: aacenc.h:376
FFPsyBand::energy
float energy
Definition: psymodel.h:52
AVCodecContext
main external API structure.
Definition: avcodec.h:1565
aacenc_pred.h
ff_aac_pow2sf_tab
float ff_aac_pow2sf_tab[428]
Definition: aactab.c:35
quantize_and_encode_band
static void quantize_and_encode_band(struct AACEncContext *s, PutBitContext *pb, const float *in, float *out, int size, int scale_idx, int cb, const float lambda, int rtz)
Definition: aacenc_quantization.h:273
ff_aac_encode_main_pred
void ff_aac_encode_main_pred(AACEncContext *s, SingleChannelElement *sce)
Encoder predictors data.
Definition: aacenc_pred.c:332
encode_window_bands_info
static void encode_window_bands_info(AACEncContext *s, SingleChannelElement *sce, int win, int group_len, const float lambda)
Encode band info for single window group bands.
Definition: aaccoder.c:77
aacenc_tns.h
find_max_val
static float find_max_val(int group_len, int swb_size, const float *scaled)
Definition: aacenc_utils.h:80
BandCodingPath::prev_idx
int prev_idx
pointer to the previous path point
Definition: aaccoder.c:69
ff_aac_search_for_pred
void ff_aac_search_for_pred(AACEncContext *s, SingleChannelElement *sce)
Definition: aacenc_pred.c:233
TRELLIS_STATES
#define TRELLIS_STATES
Definition: aaccoder.c:194
IndividualChannelStream::max_sfb
uint8_t max_sfb
number of scalefactor bands per group
Definition: aac.h:175
ff_aac_search_for_ltp
void ff_aac_search_for_ltp(AACEncContext *s, SingleChannelElement *sce, int common_window)
Mark LTP sfb's.
Definition: aacenc_ltp.c:159
TrellisPath::cost
float cost
Definition: aaccoder.c:189
quantize_band_cost
static float quantize_band_cost(struct AACEncContext *s, const float *in, const float *scaled, int size, int scale_idx, int cb, const float lambda, const float uplim, int *bits, float *energy, int rtz)
Definition: aacenc_quantization.h:250
FFPsyBand::spread
float spread
Definition: psymodel.h:54
aacenc_utils.h
put_bits.h
SingleChannelElement::band_type
enum BandType band_type[128]
band types
Definition: aac.h:252
BandCodingPath::run
int run
Definition: aaccoder.c:71
ff_quantize_band_cost_cache_init
void ff_quantize_band_cost_cache_init(struct AACEncContext *s)
Definition: aacenc.c:127
aaccoder_trellis.h
NOISE_LAMBDA_REPLACE
#define NOISE_LAMBDA_REPLACE
Definition: aaccoder.c:61
aacenc.h
BandCodingPath::cost
float cost
path cost
Definition: aaccoder.c:70
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