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Replace 5 with AOT_SBR when referring to the MPEG-4 audio object type.
[FFMpeg-mirror/lagarith.git] / libavcodec / aaccoder.c
blobbe954dd9f8f31b03303b14b6363b011e5189bbdc
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 libavcodec/aaccoder.c
24 * AAC coefficients encoder
25 */
26
27 /***********************************
28 * TODOs:
29 * speedup quantizer selection
30 * add sane pulse detection
31 ***********************************/
32
33 #include "avcodec.h"
34 #include "put_bits.h"
35 #include "aac.h"
36 #include "aacenc.h"
37 #include "aactab.h"
38
39 /** bits needed to code codebook run value for long windows */
40 static const uint8_t run_value_bits_long[64] = {
41 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
42 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 10,
43 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
44 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 15
45 };
46
47 /** bits needed to code codebook run value for short windows */
48 static const uint8_t run_value_bits_short[16] = {
49 3, 3, 3, 3, 3, 3, 3, 6, 6, 6, 6, 6, 6, 6, 6, 9
50 };
51
52 static const uint8_t *run_value_bits[2] = {
53 run_value_bits_long, run_value_bits_short
54 };
55
56
57 /**
58 * Quantize one coefficient.
59 * @return absolute value of the quantized coefficient
60 * @see 3GPP TS26.403 5.6.2 "Scalefactor determination"
61 */
62 static av_always_inline int quant(float coef, const float Q)
63 {
64 float a = coef * Q;
65 return sqrtf(a * sqrtf(a)) + 0.4054;
66 }
67
68 static void quantize_bands(int (*out)[2], const float *in, const float *scaled,
69 int size, float Q34, int is_signed, int maxval)
70 {
71 int i;
72 double qc;
73 for (i = 0; i < size; i++) {
74 qc = scaled[i] * Q34;
75 out[i][0] = (int)FFMIN(qc, (double)maxval);
76 out[i][1] = (int)FFMIN(qc + 0.4054, (double)maxval);
77 if (is_signed && in[i] < 0.0f) {
78 out[i][0] = -out[i][0];
79 out[i][1] = -out[i][1];
80 }
81 }
82 }
83
84 static void abs_pow34_v(float *out, const float *in, const int size)
85 {
86 #ifndef USE_REALLY_FULL_SEARCH
87 int i;
88 for (i = 0; i < size; i++) {
89 float a = fabsf(in[i]);
90 out[i] = sqrtf(a * sqrtf(a));
91 }
92 #endif /* USE_REALLY_FULL_SEARCH */
93 }
94
95 static const uint8_t aac_cb_range [12] = {0, 3, 3, 3, 3, 9, 9, 8, 8, 13, 13, 17};
96 static const uint8_t aac_cb_maxval[12] = {0, 1, 1, 2, 2, 4, 4, 7, 7, 12, 12, 16};
97
98 /**
99 * Calculate rate distortion cost for quantizing with given codebook
100 *
101 * @return quantization distortion
102 */
103 static float quantize_band_cost(struct AACEncContext *s, const float *in,
104 const float *scaled, int size, int scale_idx,
105 int cb, const float lambda, const float uplim,
106 int *bits)
107 {
108 const float IQ = ff_aac_pow2sf_tab[200 + scale_idx - SCALE_ONE_POS + SCALE_DIV_512];
109 const float Q = ff_aac_pow2sf_tab[200 - scale_idx + SCALE_ONE_POS - SCALE_DIV_512];
110 const float CLIPPED_ESCAPE = 165140.0f*IQ;
111 int i, j, k;
112 float cost = 0;
113 const int dim = cb < FIRST_PAIR_BT ? 4 : 2;
114 int resbits = 0;
115 #ifndef USE_REALLY_FULL_SEARCH
116 const float Q34 = sqrtf(Q * sqrtf(Q));
117 const int range = aac_cb_range[cb];
118 const int maxval = aac_cb_maxval[cb];
119 int offs[4];
120 #endif /* USE_REALLY_FULL_SEARCH */
121
122 if (!cb) {
123 for (i = 0; i < size; i++)
124 cost += in[i]*in[i]*lambda;
125 if (bits)
126 *bits = 0;
127 return cost;
128 }
129 #ifndef USE_REALLY_FULL_SEARCH
130 offs[0] = 1;
131 for (i = 1; i < dim; i++)
132 offs[i] = offs[i-1]*range;
133 quantize_bands(s->qcoefs, in, scaled, size, Q34, !IS_CODEBOOK_UNSIGNED(cb), maxval);
134 #endif /* USE_REALLY_FULL_SEARCH */
135 for (i = 0; i < size; i += dim) {
136 float mincost;
137 int minidx = 0;
138 int minbits = 0;
139 const float *vec;
140 #ifndef USE_REALLY_FULL_SEARCH
141 int (*quants)[2] = &s->qcoefs[i];
142 mincost = 0.0f;
143 for (j = 0; j < dim; j++)
144 mincost += in[i+j]*in[i+j]*lambda;
145 minidx = IS_CODEBOOK_UNSIGNED(cb) ? 0 : 40;
146 minbits = ff_aac_spectral_bits[cb-1][minidx];
147 mincost += minbits;
148 for (j = 0; j < (1<<dim); j++) {
149 float rd = 0.0f;
150 int curbits;
151 int curidx = IS_CODEBOOK_UNSIGNED(cb) ? 0 : 40;
152 int same = 0;
153 for (k = 0; k < dim; k++) {
154 if ((j & (1 << k)) && quants[k][0] == quants[k][1]) {
155 same = 1;
156 break;
157 }
158 }
159 if (same)
160 continue;
161 for (k = 0; k < dim; k++)
162 curidx += quants[k][!!(j & (1 << k))] * offs[dim - 1 - k];
163 curbits = ff_aac_spectral_bits[cb-1][curidx];
164 vec = &ff_aac_codebook_vectors[cb-1][curidx*dim];
165 #else
166 mincost = INFINITY;
167 vec = ff_aac_codebook_vectors[cb-1];
168 for (j = 0; j < ff_aac_spectral_sizes[cb-1]; j++, vec += dim) {
169 float rd = 0.0f;
170 int curbits = ff_aac_spectral_bits[cb-1][j];
171 #endif /* USE_REALLY_FULL_SEARCH */
172 if (IS_CODEBOOK_UNSIGNED(cb)) {
173 for (k = 0; k < dim; k++) {
174 float t = fabsf(in[i+k]);
175 float di;
176 //do not code with escape sequence small values
177 if (vec[k] == 64.0f && t < 39.0f*IQ) {
178 rd = INFINITY;
179 break;
180 }
181 if (vec[k] == 64.0f) { //FIXME: slow
182 if (t >= CLIPPED_ESCAPE) {
183 di = t - CLIPPED_ESCAPE;
184 curbits += 21;
185 } else {
186 int c = av_clip(quant(t, Q), 0, 8191);
187 di = t - c*cbrt(c)*IQ;
188 curbits += av_log2(c)*2 - 4 + 1;
189 }
190 } else {
191 di = t - vec[k]*IQ;
192 }
193 if (vec[k] != 0.0f)
194 curbits++;
195 rd += di*di*lambda;
196 }
197 } else {
198 for (k = 0; k < dim; k++) {
199 float di = in[i+k] - vec[k]*IQ;
200 rd += di*di*lambda;
201 }
202 }
203 rd += curbits;
204 if (rd < mincost) {
205 mincost = rd;
206 minidx = j;
207 minbits = curbits;
208 }
209 }
210 cost += mincost;
211 resbits += minbits;
212 if (cost >= uplim)
213 return uplim;
214 }
215
216 if (bits)
217 *bits = resbits;
218 return cost;
219 }
220
221 static void quantize_and_encode_band(struct AACEncContext *s, PutBitContext *pb,
222 const float *in, int size, int scale_idx,
223 int cb, const float lambda)
224 {
225 const float IQ = ff_aac_pow2sf_tab[200 + scale_idx - SCALE_ONE_POS + SCALE_DIV_512];
226 const float Q = ff_aac_pow2sf_tab[200 - scale_idx + SCALE_ONE_POS - SCALE_DIV_512];
227 const float CLIPPED_ESCAPE = 165140.0f*IQ;
228 const int dim = (cb < FIRST_PAIR_BT) ? 4 : 2;
229 int i, j, k;
230 #ifndef USE_REALLY_FULL_SEARCH
231 const float Q34 = sqrtf(Q * sqrtf(Q));
232 const int range = aac_cb_range[cb];
233 const int maxval = aac_cb_maxval[cb];
234 int offs[4];
235 float *scaled = s->scoefs;
236 #endif /* USE_REALLY_FULL_SEARCH */
237
238 //START_TIMER
239 if (!cb)
240 return;
241
242 #ifndef USE_REALLY_FULL_SEARCH
243 offs[0] = 1;
244 for (i = 1; i < dim; i++)
245 offs[i] = offs[i-1]*range;
246 abs_pow34_v(scaled, in, size);
247 quantize_bands(s->qcoefs, in, scaled, size, Q34, !IS_CODEBOOK_UNSIGNED(cb), maxval);
248 #endif /* USE_REALLY_FULL_SEARCH */
249 for (i = 0; i < size; i += dim) {
250 float mincost;
251 int minidx = 0;
252 int minbits = 0;
253 const float *vec;
254 #ifndef USE_REALLY_FULL_SEARCH
255 int (*quants)[2] = &s->qcoefs[i];
256 mincost = 0.0f;
257 for (j = 0; j < dim; j++)
258 mincost += in[i+j]*in[i+j]*lambda;
259 minidx = IS_CODEBOOK_UNSIGNED(cb) ? 0 : 40;
260 minbits = ff_aac_spectral_bits[cb-1][minidx];
261 mincost += minbits;
262 for (j = 0; j < (1<<dim); j++) {
263 float rd = 0.0f;
264 int curbits;
265 int curidx = IS_CODEBOOK_UNSIGNED(cb) ? 0 : 40;
266 int same = 0;
267 for (k = 0; k < dim; k++) {
268 if ((j & (1 << k)) && quants[k][0] == quants[k][1]) {
269 same = 1;
270 break;
271 }
272 }
273 if (same)
274 continue;
275 for (k = 0; k < dim; k++)
276 curidx += quants[k][!!(j & (1 << k))] * offs[dim - 1 - k];
277 curbits = ff_aac_spectral_bits[cb-1][curidx];
278 vec = &ff_aac_codebook_vectors[cb-1][curidx*dim];
279 #else
280 vec = ff_aac_codebook_vectors[cb-1];
281 mincost = INFINITY;
282 for (j = 0; j < ff_aac_spectral_sizes[cb-1]; j++, vec += dim) {
283 float rd = 0.0f;
284 int curbits = ff_aac_spectral_bits[cb-1][j];
285 int curidx = j;
286 #endif /* USE_REALLY_FULL_SEARCH */
287 if (IS_CODEBOOK_UNSIGNED(cb)) {
288 for (k = 0; k < dim; k++) {
289 float t = fabsf(in[i+k]);
290 float di;
291 //do not code with escape sequence small values
292 if (vec[k] == 64.0f && t < 39.0f*IQ) {
293 rd = INFINITY;
294 break;
295 }
296 if (vec[k] == 64.0f) { //FIXME: slow
297 if (t >= CLIPPED_ESCAPE) {
298 di = t - CLIPPED_ESCAPE;
299 curbits += 21;
300 } else {
301 int c = av_clip(quant(t, Q), 0, 8191);
302 di = t - c*cbrt(c)*IQ;
303 curbits += av_log2(c)*2 - 4 + 1;
304 }
305 } else {
306 di = t - vec[k]*IQ;
307 }
308 if (vec[k] != 0.0f)
309 curbits++;
310 rd += di*di*lambda;
311 }
312 } else {
313 for (k = 0; k < dim; k++) {
314 float di = in[i+k] - vec[k]*IQ;
315 rd += di*di*lambda;
316 }
317 }
318 rd += curbits;
319 if (rd < mincost) {
320 mincost = rd;
321 minidx = curidx;
322 minbits = curbits;
323 }
324 }
325 put_bits(pb, ff_aac_spectral_bits[cb-1][minidx], ff_aac_spectral_codes[cb-1][minidx]);
326 if (IS_CODEBOOK_UNSIGNED(cb))
327 for (j = 0; j < dim; j++)
328 if (ff_aac_codebook_vectors[cb-1][minidx*dim+j] != 0.0f)
329 put_bits(pb, 1, in[i+j] < 0.0f);
330 if (cb == ESC_BT) {
331 for (j = 0; j < 2; j++) {
332 if (ff_aac_codebook_vectors[cb-1][minidx*2+j] == 64.0f) {
333 int coef = av_clip(quant(fabsf(in[i+j]), Q), 0, 8191);
334 int len = av_log2(coef);
335
336 put_bits(pb, len - 4 + 1, (1 << (len - 4 + 1)) - 2);
337 put_bits(pb, len, coef & ((1 << len) - 1));
338 }
339 }
340 }
341 }
342 //STOP_TIMER("quantize_and_encode")
343 }
344
345 /**
346 * structure used in optimal codebook search
347 */
348 typedef struct BandCodingPath {
349 int prev_idx; ///< pointer to the previous path point
350 float cost; ///< path cost
351 int run;
352 } BandCodingPath;
353
354 /**
355 * Encode band info for single window group bands.
356 */
357 static void encode_window_bands_info(AACEncContext *s, SingleChannelElement *sce,
358 int win, int group_len, const float lambda)
359 {
360 BandCodingPath path[120][12];
361 int w, swb, cb, start, start2, size;
362 int i, j;
363 const int max_sfb = sce->ics.max_sfb;
364 const int run_bits = sce->ics.num_windows == 1 ? 5 : 3;
365 const int run_esc = (1 << run_bits) - 1;
366 int idx, ppos, count;
367 int stackrun[120], stackcb[120], stack_len;
368 float next_minrd = INFINITY;
369 int next_mincb = 0;
370
371 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
372 start = win*128;
373 for (cb = 0; cb < 12; cb++) {
374 path[0][cb].cost = 0.0f;
375 path[0][cb].prev_idx = -1;
376 path[0][cb].run = 0;
377 }
378 for (swb = 0; swb < max_sfb; swb++) {
379 start2 = start;
380 size = sce->ics.swb_sizes[swb];
381 if (sce->zeroes[win*16 + swb]) {
382 for (cb = 0; cb < 12; cb++) {
383 path[swb+1][cb].prev_idx = cb;
384 path[swb+1][cb].cost = path[swb][cb].cost;
385 path[swb+1][cb].run = path[swb][cb].run + 1;
386 }
387 } else {
388 float minrd = next_minrd;
389 int mincb = next_mincb;
390 next_minrd = INFINITY;
391 next_mincb = 0;
392 for (cb = 0; cb < 12; cb++) {
393 float cost_stay_here, cost_get_here;
394 float rd = 0.0f;
395 for (w = 0; w < group_len; w++) {
396 FFPsyBand *band = &s->psy.psy_bands[s->cur_channel*PSY_MAX_BANDS+(win+w)*16+swb];
397 rd += quantize_band_cost(s, sce->coeffs + start + w*128,
398 s->scoefs + start + w*128, size,
399 sce->sf_idx[(win+w)*16+swb], cb,
400 lambda / band->threshold, INFINITY, NULL);
401 }
402 cost_stay_here = path[swb][cb].cost + rd;
403 cost_get_here = minrd + rd + run_bits + 4;
404 if ( run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run]
405 != run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1])
406 cost_stay_here += run_bits;
407 if (cost_get_here < cost_stay_here) {
408 path[swb+1][cb].prev_idx = mincb;
409 path[swb+1][cb].cost = cost_get_here;
410 path[swb+1][cb].run = 1;
411 } else {
412 path[swb+1][cb].prev_idx = cb;
413 path[swb+1][cb].cost = cost_stay_here;
414 path[swb+1][cb].run = path[swb][cb].run + 1;
415 }
416 if (path[swb+1][cb].cost < next_minrd) {
417 next_minrd = path[swb+1][cb].cost;
418 next_mincb = cb;
419 }
420 }
421 }
422 start += sce->ics.swb_sizes[swb];
423 }
424
425 //convert resulting path from backward-linked list
426 stack_len = 0;
427 idx = 0;
428 for (cb = 1; cb < 12; cb++)
429 if (path[max_sfb][cb].cost < path[max_sfb][idx].cost)
430 idx = cb;
431 ppos = max_sfb;
432 while (ppos > 0) {
433 cb = idx;
434 stackrun[stack_len] = path[ppos][cb].run;
435 stackcb [stack_len] = cb;
436 idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx;
437 ppos -= path[ppos][cb].run;
438 stack_len++;
439 }
440 //perform actual band info encoding
441 start = 0;
442 for (i = stack_len - 1; i >= 0; i--) {
443 put_bits(&s->pb, 4, stackcb[i]);
444 count = stackrun[i];
445 memset(sce->zeroes + win*16 + start, !stackcb[i], count);
446 //XXX: memset when band_type is also uint8_t
447 for (j = 0; j < count; j++) {
448 sce->band_type[win*16 + start] = stackcb[i];
449 start++;
450 }
451 while (count >= run_esc) {
452 put_bits(&s->pb, run_bits, run_esc);
453 count -= run_esc;
454 }
455 put_bits(&s->pb, run_bits, count);
456 }
457 }
458
459 typedef struct TrellisPath {
460 float cost;
461 int prev;
462 int min_val;
463 int max_val;
464 } TrellisPath;
465
466 static void search_for_quantizers_anmr(AVCodecContext *avctx, AACEncContext *s,
467 SingleChannelElement *sce,
468 const float lambda)
469 {
470 int q, w, w2, g, start = 0;
471 int i;
472 int idx;
473 TrellisPath paths[256*121];
474 int bandaddr[121];
475 int minq;
476 float mincost;
477
478 for (i = 0; i < 256; i++) {
479 paths[i].cost = 0.0f;
480 paths[i].prev = -1;
481 paths[i].min_val = i;
482 paths[i].max_val = i;
483 }
484 for (i = 256; i < 256*121; i++) {
485 paths[i].cost = INFINITY;
486 paths[i].prev = -2;
487 paths[i].min_val = INT_MAX;
488 paths[i].max_val = 0;
489 }
490 idx = 256;
491 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
492 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
493 start = w*128;
494 for (g = 0; g < sce->ics.num_swb; g++) {
495 const float *coefs = sce->coeffs + start;
496 float qmin, qmax;
497 int nz = 0;
498
499 bandaddr[idx >> 8] = w * 16 + g;
500 qmin = INT_MAX;
501 qmax = 0.0f;
502 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
503 FFPsyBand *band = &s->psy.psy_bands[s->cur_channel*PSY_MAX_BANDS+(w+w2)*16+g];
504 if (band->energy <= band->threshold || band->threshold == 0.0f) {
505 sce->zeroes[(w+w2)*16+g] = 1;
506 continue;
507 }
508 sce->zeroes[(w+w2)*16+g] = 0;
509 nz = 1;
510 for (i = 0; i < sce->ics.swb_sizes[g]; i++) {
511 float t = fabsf(coefs[w2*128+i]);
512 if (t > 0.0f)
513 qmin = FFMIN(qmin, t);
514 qmax = FFMAX(qmax, t);
515 }
516 }
517 if (nz) {
518 int minscale, maxscale;
519 float minrd = INFINITY;
520 //minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped
521 minscale = av_clip_uint8(log2(qmin)*4 - 69 + SCALE_ONE_POS - SCALE_DIV_512);
522 //maximum scalefactor index is when maximum coefficient after quantizing is still not zero
523 maxscale = av_clip_uint8(log2(qmax)*4 + 6 + SCALE_ONE_POS - SCALE_DIV_512);
524 for (q = minscale; q < maxscale; q++) {
525 float dists[12], dist;
526 memset(dists, 0, sizeof(dists));
527 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
528 FFPsyBand *band = &s->psy.psy_bands[s->cur_channel*PSY_MAX_BANDS+(w+w2)*16+g];
529 int cb;
530 for (cb = 0; cb <= ESC_BT; cb++)
531 dists[cb] += quantize_band_cost(s, coefs + w2*128, s->scoefs + start + w2*128, sce->ics.swb_sizes[g],
532 q, cb, lambda / band->threshold, INFINITY, NULL);
533 }
534 dist = dists[0];
535 for (i = 1; i <= ESC_BT; i++)
536 dist = FFMIN(dist, dists[i]);
537 minrd = FFMIN(minrd, dist);
538
539 for (i = FFMAX(q - SCALE_MAX_DIFF, 0); i < FFMIN(q + SCALE_MAX_DIFF, 256); i++) {
540 float cost;
541 int minv, maxv;
542 if (isinf(paths[idx - 256 + i].cost))
543 continue;
544 cost = paths[idx - 256 + i].cost + dist
545 + ff_aac_scalefactor_bits[q - i + SCALE_DIFF_ZERO];
546 minv = FFMIN(paths[idx - 256 + i].min_val, q);
547 maxv = FFMAX(paths[idx - 256 + i].max_val, q);
548 if (cost < paths[idx + q].cost && maxv-minv < SCALE_MAX_DIFF) {
549 paths[idx + q].cost = cost;
550 paths[idx + q].prev = idx - 256 + i;
551 paths[idx + q].min_val = minv;
552 paths[idx + q].max_val = maxv;
553 }
554 }
555 }
556 } else {
557 for (q = 0; q < 256; q++) {
558 if (!isinf(paths[idx - 256 + q].cost)) {
559 paths[idx + q].cost = paths[idx - 256 + q].cost + 1;
560 paths[idx + q].prev = idx - 256 + q;
561 paths[idx + q].min_val = FFMIN(paths[idx - 256 + q].min_val, q);
562 paths[idx + q].max_val = FFMAX(paths[idx - 256 + q].max_val, q);
563 continue;
564 }
565 for (i = FFMAX(q - SCALE_MAX_DIFF, 0); i < FFMIN(q + SCALE_MAX_DIFF, 256); i++) {
566 float cost;
567 int minv, maxv;
568 if (isinf(paths[idx - 256 + i].cost))
569 continue;
570 cost = paths[idx - 256 + i].cost + ff_aac_scalefactor_bits[q - i + SCALE_DIFF_ZERO];
571 minv = FFMIN(paths[idx - 256 + i].min_val, q);
572 maxv = FFMAX(paths[idx - 256 + i].max_val, q);
573 if (cost < paths[idx + q].cost && maxv-minv < SCALE_MAX_DIFF) {
574 paths[idx + q].cost = cost;
575 paths[idx + q].prev = idx - 256 + i;
576 paths[idx + q].min_val = minv;
577 paths[idx + q].max_val = maxv;
578 }
579 }
580 }
581 }
582 sce->zeroes[w*16+g] = !nz;
583 start += sce->ics.swb_sizes[g];
584 idx += 256;
585 }
586 }
587 idx -= 256;
588 mincost = paths[idx].cost;
589 minq = idx;
590 for (i = 1; i < 256; i++) {
591 if (paths[idx + i].cost < mincost) {
592 mincost = paths[idx + i].cost;
593 minq = idx + i;
594 }
595 }
596 while (minq >= 256) {
597 sce->sf_idx[bandaddr[minq>>8]] = minq & 0xFF;
598 minq = paths[minq].prev;
599 }
600 //set the same quantizers inside window groups
601 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
602 for (g = 0; g < sce->ics.num_swb; g++)
603 for (w2 = 1; w2 < sce->ics.group_len[w]; w2++)
604 sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g];
605 }
606
607 /**
608 * two-loop quantizers search taken from ISO 13818-7 Appendix C
609 */
610 static void search_for_quantizers_twoloop(AVCodecContext *avctx,
611 AACEncContext *s,
612 SingleChannelElement *sce,
613 const float lambda)
614 {
615 int start = 0, i, w, w2, g;
616 int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->channels;
617 float dists[128], uplims[128];
618 int fflag, minscaler;
619 int its = 0;
620 int allz = 0;
621 float minthr = INFINITY;
622
623 //XXX: some heuristic to determine initial quantizers will reduce search time
624 memset(dists, 0, sizeof(dists));
625 //determine zero bands and upper limits
626 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
627 for (g = 0; g < sce->ics.num_swb; g++) {
628 int nz = 0;
629 float uplim = 0.0f;
630 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
631 FFPsyBand *band = &s->psy.psy_bands[s->cur_channel*PSY_MAX_BANDS+(w+w2)*16+g];
632 uplim += band->threshold;
633 if (band->energy <= band->threshold || band->threshold == 0.0f) {
634 sce->zeroes[(w+w2)*16+g] = 1;
635 continue;
636 }
637 nz = 1;
638 }
639 uplims[w*16+g] = uplim *512;
640 sce->zeroes[w*16+g] = !nz;
641 if (nz)
642 minthr = FFMIN(minthr, uplim);
643 allz = FFMAX(allz, nz);
644 }
645 }
646 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
647 for (g = 0; g < sce->ics.num_swb; g++) {
648 if (sce->zeroes[w*16+g]) {
649 sce->sf_idx[w*16+g] = SCALE_ONE_POS;
650 continue;
651 }
652 sce->sf_idx[w*16+g] = SCALE_ONE_POS + FFMIN(log2(uplims[w*16+g]/minthr)*4,59);
653 }
654 }
655
656 if (!allz)
657 return;
658 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
659 //perform two-loop search
660 //outer loop - improve quality
661 do {
662 int tbits, qstep;
663 minscaler = sce->sf_idx[0];
664 //inner loop - quantize spectrum to fit into given number of bits
665 qstep = its ? 1 : 32;
666 do {
667 int prev = -1;
668 tbits = 0;
669 fflag = 0;
670 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
671 start = w*128;
672 for (g = 0; g < sce->ics.num_swb; g++) {
673 const float *coefs = sce->coeffs + start;
674 const float *scaled = s->scoefs + start;
675 int bits = 0;
676 int cb;
677 float mindist = INFINITY;
678 int minbits = 0;
679
680 if (sce->zeroes[w*16+g] || sce->sf_idx[w*16+g] >= 218) {
681 start += sce->ics.swb_sizes[g];
682 continue;
683 }
684 minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]);
685 for (cb = 0; cb <= ESC_BT; cb++) {
686 float dist = 0.0f;
687 int bb = 0;
688 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
689 int b;
690 dist += quantize_band_cost(s, coefs + w2*128,
691 scaled + w2*128,
692 sce->ics.swb_sizes[g],
693 sce->sf_idx[w*16+g],
694 cb,
695 lambda,
696 INFINITY,
697 &b);
698 bb += b;
699 }
700 if (dist < mindist) {
701 mindist = dist;
702 minbits = bb;
703 }
704 }
705 dists[w*16+g] = (mindist - minbits) / lambda;
706 bits = minbits;
707 if (prev != -1) {
708 bits += ff_aac_scalefactor_bits[sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO];
709 }
710 tbits += bits;
711 start += sce->ics.swb_sizes[g];
712 prev = sce->sf_idx[w*16+g];
713 }
714 }
715 if (tbits > destbits) {
716 for (i = 0; i < 128; i++)
717 if (sce->sf_idx[i] < 218 - qstep)
718 sce->sf_idx[i] += qstep;
719 } else {
720 for (i = 0; i < 128; i++)
721 if (sce->sf_idx[i] > 60 - qstep)
722 sce->sf_idx[i] -= qstep;
723 }
724 qstep >>= 1;
725 if (!qstep && tbits > destbits*1.02)
726 qstep = 1;
727 if (sce->sf_idx[0] >= 217)
728 break;
729 } while (qstep);
730
731 fflag = 0;
732 minscaler = av_clip(minscaler, 60, 255 - SCALE_MAX_DIFF);
733 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
734 start = w*128;
735 for (g = 0; g < sce->ics.num_swb; g++) {
736 int prevsc = sce->sf_idx[w*16+g];
737 if (dists[w*16+g] > uplims[w*16+g] && sce->sf_idx[w*16+g] > 60)
738 sce->sf_idx[w*16+g]--;
739 sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], minscaler, minscaler + SCALE_MAX_DIFF);
740 sce->sf_idx[w*16+g] = FFMIN(sce->sf_idx[w*16+g], 219);
741 if (sce->sf_idx[w*16+g] != prevsc)
742 fflag = 1;
743 }
744 }
745 its++;
746 } while (fflag && its < 10);
747 }
748
749 static void search_for_quantizers_faac(AVCodecContext *avctx, AACEncContext *s,
750 SingleChannelElement *sce,
751 const float lambda)
752 {
753 int start = 0, i, w, w2, g;
754 float uplim[128], maxq[128];
755 int minq, maxsf;
756 float distfact = ((sce->ics.num_windows > 1) ? 85.80 : 147.84) / lambda;
757 int last = 0, lastband = 0, curband = 0;
758 float avg_energy = 0.0;
759 if (sce->ics.num_windows == 1) {
760 start = 0;
761 for (i = 0; i < 1024; i++) {
762 if (i - start >= sce->ics.swb_sizes[curband]) {
763 start += sce->ics.swb_sizes[curband];
764 curband++;
765 }
766 if (sce->coeffs[i]) {
767 avg_energy += sce->coeffs[i] * sce->coeffs[i];
768 last = i;
769 lastband = curband;
770 }
771 }
772 } else {
773 for (w = 0; w < 8; w++) {
774 const float *coeffs = sce->coeffs + w*128;
775 start = 0;
776 for (i = 0; i < 128; i++) {
777 if (i - start >= sce->ics.swb_sizes[curband]) {
778 start += sce->ics.swb_sizes[curband];
779 curband++;
780 }
781 if (coeffs[i]) {
782 avg_energy += coeffs[i] * coeffs[i];
783 last = FFMAX(last, i);
784 lastband = FFMAX(lastband, curband);
785 }
786 }
787 }
788 }
789 last++;
790 avg_energy /= last;
791 if (avg_energy == 0.0f) {
792 for (i = 0; i < FF_ARRAY_ELEMS(sce->sf_idx); i++)
793 sce->sf_idx[i] = SCALE_ONE_POS;
794 return;
795 }
796 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
797 start = w*128;
798 for (g = 0; g < sce->ics.num_swb; g++) {
799 float *coefs = sce->coeffs + start;
800 const int size = sce->ics.swb_sizes[g];
801 int start2 = start, end2 = start + size, peakpos = start;
802 float maxval = -1, thr = 0.0f, t;
803 maxq[w*16+g] = 0.0f;
804 if (g > lastband) {
805 maxq[w*16+g] = 0.0f;
806 start += size;
807 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++)
808 memset(coefs + w2*128, 0, sizeof(coefs[0])*size);
809 continue;
810 }
811 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
812 for (i = 0; i < size; i++) {
813 float t = coefs[w2*128+i]*coefs[w2*128+i];
814 maxq[w*16+g] = FFMAX(maxq[w*16+g], fabsf(coefs[w2*128 + i]));
815 thr += t;
816 if (sce->ics.num_windows == 1 && maxval < t) {
817 maxval = t;
818 peakpos = start+i;
819 }
820 }
821 }
822 if (sce->ics.num_windows == 1) {
823 start2 = FFMAX(peakpos - 2, start2);
824 end2 = FFMIN(peakpos + 3, end2);
825 } else {
826 start2 -= start;
827 end2 -= start;
828 }
829 start += size;
830 thr = pow(thr / (avg_energy * (end2 - start2)), 0.3 + 0.1*(lastband - g) / lastband);
831 t = 1.0 - (1.0 * start2 / last);
832 uplim[w*16+g] = distfact / (1.4 * thr + t*t*t + 0.075);
833 }
834 }
835 memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
836 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
837 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
838 start = w*128;
839 for (g = 0; g < sce->ics.num_swb; g++) {
840 const float *coefs = sce->coeffs + start;
841 const float *scaled = s->scoefs + start;
842 const int size = sce->ics.swb_sizes[g];
843 int scf, prev_scf, step;
844 int min_scf = 0, max_scf = 255;
845 float curdiff;
846 if (maxq[w*16+g] < 21.544) {
847 sce->zeroes[w*16+g] = 1;
848 start += size;
849 continue;
850 }
851 sce->zeroes[w*16+g] = 0;
852 scf = prev_scf = av_clip(SCALE_ONE_POS - SCALE_DIV_512 - log2(1/maxq[w*16+g])*16/3, 60, 218);
853 step = 16;
854 for (;;) {
855 float dist = 0.0f;
856 int quant_max;
857
858 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
859 int b;
860 dist += quantize_band_cost(s, coefs + w2*128,
861 scaled + w2*128,
862 sce->ics.swb_sizes[g],
863 scf,
864 ESC_BT,
865 lambda,
866 INFINITY,
867 &b);
868 dist -= b;
869 }
870 dist *= 1.0f / 512.0f / lambda;
871 quant_max = quant(maxq[w*16+g], ff_aac_pow2sf_tab[200 - scf + SCALE_ONE_POS - SCALE_DIV_512]);
872 if (quant_max >= 8191) { // too much, return to the previous quantizer
873 sce->sf_idx[w*16+g] = prev_scf;
874 break;
875 }
876 prev_scf = scf;
877 curdiff = fabsf(dist - uplim[w*16+g]);
878 if (curdiff == 0.0f)
879 step = 0;
880 else
881 step = fabsf(log2(curdiff));
882 if (dist > uplim[w*16+g])
883 step = -step;
884 if (FFABS(step) <= 1 || (step > 0 && scf >= max_scf) || (step < 0 && scf <= min_scf)) {
885 sce->sf_idx[w*16+g] = scf;
886 break;
887 }
888 scf += step;
889 if (step > 0)
890 min_scf = scf;
891 else
892 max_scf = scf;
893 }
894 start += size;
895 }
896 }
897 minq = sce->sf_idx[0] ? sce->sf_idx[0] : INT_MAX;
898 for (i = 1; i < 128; i++) {
899 if (!sce->sf_idx[i])
900 sce->sf_idx[i] = sce->sf_idx[i-1];
901 else
902 minq = FFMIN(minq, sce->sf_idx[i]);
903 }
904 if (minq == INT_MAX)
905 minq = 0;
906 minq = FFMIN(minq, SCALE_MAX_POS);
907 maxsf = FFMIN(minq + SCALE_MAX_DIFF, SCALE_MAX_POS);
908 for (i = 126; i >= 0; i--) {
909 if (!sce->sf_idx[i])
910 sce->sf_idx[i] = sce->sf_idx[i+1];
911 sce->sf_idx[i] = av_clip(sce->sf_idx[i], minq, maxsf);
912 }
913 }
914
915 static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s,
916 SingleChannelElement *sce,
917 const float lambda)
918 {
919 int start = 0, i, w, w2, g;
920 int minq = 255;
921
922 memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
923 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
924 start = w*128;
925 for (g = 0; g < sce->ics.num_swb; g++) {
926 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
927 FFPsyBand *band = &s->psy.psy_bands[s->cur_channel*PSY_MAX_BANDS+(w+w2)*16+g];
928 if (band->energy <= band->threshold) {
929 sce->sf_idx[(w+w2)*16+g] = 218;
930 sce->zeroes[(w+w2)*16+g] = 1;
931 } else {
932 sce->sf_idx[(w+w2)*16+g] = av_clip(SCALE_ONE_POS - SCALE_DIV_512 + log2(band->threshold), 80, 218);
933 sce->zeroes[(w+w2)*16+g] = 0;
934 }
935 minq = FFMIN(minq, sce->sf_idx[(w+w2)*16+g]);
936 }
937 }
938 }
939 for (i = 0; i < 128; i++) {
940 sce->sf_idx[i] = 140;
941 //av_clip(sce->sf_idx[i], minq, minq + SCALE_MAX_DIFF - 1);
942 }
943 //set the same quantizers inside window groups
944 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
945 for (g = 0; g < sce->ics.num_swb; g++)
946 for (w2 = 1; w2 < sce->ics.group_len[w]; w2++)
947 sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g];
948 }
949
950 static void search_for_ms(AACEncContext *s, ChannelElement *cpe,
951 const float lambda)
952 {
953 int start = 0, i, w, w2, g;
954 float M[128], S[128];
955 float *L34 = s->scoefs, *R34 = s->scoefs + 128, *M34 = s->scoefs + 128*2, *S34 = s->scoefs + 128*3;
956 SingleChannelElement *sce0 = &cpe->ch[0];
957 SingleChannelElement *sce1 = &cpe->ch[1];
958 if (!cpe->common_window)
959 return;
960 for (w = 0; w < sce0->ics.num_windows; w += sce0->ics.group_len[w]) {
961 for (g = 0; g < sce0->ics.num_swb; g++) {
962 if (!cpe->ch[0].zeroes[w*16+g] && !cpe->ch[1].zeroes[w*16+g]) {
963 float dist1 = 0.0f, dist2 = 0.0f;
964 for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) {
965 FFPsyBand *band0 = &s->psy.psy_bands[(s->cur_channel+0)*PSY_MAX_BANDS+(w+w2)*16+g];
966 FFPsyBand *band1 = &s->psy.psy_bands[(s->cur_channel+1)*PSY_MAX_BANDS+(w+w2)*16+g];
967 float minthr = FFMIN(band0->threshold, band1->threshold);
968 float maxthr = FFMAX(band0->threshold, band1->threshold);
969 for (i = 0; i < sce0->ics.swb_sizes[g]; i++) {
970 M[i] = (sce0->coeffs[start+w2*128+i]
971 + sce1->coeffs[start+w2*128+i]) * 0.5;
972 S[i] = sce0->coeffs[start+w2*128+i]
973 - sce1->coeffs[start+w2*128+i];
974 }
975 abs_pow34_v(L34, sce0->coeffs+start+w2*128, sce0->ics.swb_sizes[g]);
976 abs_pow34_v(R34, sce1->coeffs+start+w2*128, sce0->ics.swb_sizes[g]);
977 abs_pow34_v(M34, M, sce0->ics.swb_sizes[g]);
978 abs_pow34_v(S34, S, sce0->ics.swb_sizes[g]);
979 dist1 += quantize_band_cost(s, sce0->coeffs + start + w2*128,
980 L34,
981 sce0->ics.swb_sizes[g],
982 sce0->sf_idx[(w+w2)*16+g],
983 sce0->band_type[(w+w2)*16+g],
984 lambda / band0->threshold, INFINITY, NULL);
985 dist1 += quantize_band_cost(s, sce1->coeffs + start + w2*128,
986 R34,
987 sce1->ics.swb_sizes[g],
988 sce1->sf_idx[(w+w2)*16+g],
989 sce1->band_type[(w+w2)*16+g],
990 lambda / band1->threshold, INFINITY, NULL);
991 dist2 += quantize_band_cost(s, M,
992 M34,
993 sce0->ics.swb_sizes[g],
994 sce0->sf_idx[(w+w2)*16+g],
995 sce0->band_type[(w+w2)*16+g],
996 lambda / maxthr, INFINITY, NULL);
997 dist2 += quantize_band_cost(s, S,
998 S34,
999 sce1->ics.swb_sizes[g],
1000 sce1->sf_idx[(w+w2)*16+g],
1001 sce1->band_type[(w+w2)*16+g],
1002 lambda / minthr, INFINITY, NULL);
1003 }
1004 cpe->ms_mask[w*16+g] = dist2 < dist1;
1005 }
1006 start += sce0->ics.swb_sizes[g];
1007 }
1008 }
1009 }
1010
1011 AACCoefficientsEncoder ff_aac_coders[] = {
1012 {
1013 search_for_quantizers_faac,
1014 encode_window_bands_info,
1015 quantize_and_encode_band,
1016 // search_for_ms,
1017 },
1018 {
1019 search_for_quantizers_anmr,
1020 encode_window_bands_info,
1021 quantize_and_encode_band,
1022 // search_for_ms,
1023 },
1024 {
1025 search_for_quantizers_twoloop,
1026 encode_window_bands_info,
1027 quantize_and_encode_band,
1028 // search_for_ms,
1029 },
1030 {
1031 search_for_quantizers_fast,
1032 encode_window_bands_info,
1033 quantize_and_encode_band,
1034 // search_for_ms,
1035 },
1036 };
ffmpeg Lagarith lossless decoder