2 * AAC coefficients encoder
3 * Copyright (C) 2008-2009 Konstantin Shishkov
5 * This file is part of FFmpeg.
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.
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.
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
24 * AAC coefficients encoder
27 /***********************************
29 * speedup quantizer selection
30 * add sane pulse detection
31 ***********************************/
33 #include "libavutil/libm.h" // brought forward to work around cygwin header breakage
36 #include "libavutil/mathematics.h"
43 /** Frequency in Hz for lower limit of noise substitution **/
44 #define NOISE_LOW_LIMIT 4000
46 /** Total number of usable codebooks **/
49 /** bits needed to code codebook run value for long windows */
50 static const uint8_t run_value_bits_long[64] = {
51 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
52 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 10,
53 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
54 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 15
57 /** bits needed to code codebook run value for short windows */
58 static const uint8_t run_value_bits_short[16] = {
59 3, 3, 3, 3, 3, 3, 3, 6, 6, 6, 6, 6, 6, 6, 6, 9
62 static const uint8_t * const run_value_bits[2] = {
63 run_value_bits_long, run_value_bits_short
66 /** Map to convert values from BandCodingPath index to a codebook index **/
67 static const uint8_t aac_cb_out_map[CB_TOT] = {0,1,2,3,4,5,6,7,8,9,10,11,13};
68 /** Inverse map to convert from codebooks to BandCodingPath indices **/
69 static const uint8_t aac_cb_in_map[CB_TOT+1] = {0,1,2,3,4,5,6,7,8,9,10,11,0,12};
72 * Quantize one coefficient.
73 * @return absolute value of the quantized coefficient
74 * @see 3GPP TS26.403 5.6.2 "Scalefactor determination"
76 static av_always_inline int quant(float coef, const float Q)
79 return sqrtf(a * sqrtf(a)) + 0.4054;
82 static void quantize_bands(int *out, const float *in, const float *scaled,
83 int size, float Q34, int is_signed, int maxval)
87 for (i = 0; i < size; i++) {
89 out[i] = (int)FFMIN(qc + 0.4054, (double)maxval);
90 if (is_signed && in[i] < 0.0f) {
96 static void abs_pow34_v(float *out, const float *in, const int size)
98 #ifndef USE_REALLY_FULL_SEARCH
100 for (i = 0; i < size; i++) {
101 float a = fabsf(in[i]);
102 out[i] = sqrtf(a * sqrtf(a));
104 #endif /* USE_REALLY_FULL_SEARCH */
107 static const uint8_t aac_cb_range [12] = {0, 3, 3, 3, 3, 9, 9, 8, 8, 13, 13, 17};
108 static const uint8_t aac_cb_maxval[12] = {0, 1, 1, 2, 2, 4, 4, 7, 7, 12, 12, 16};
111 * Calculate rate distortion cost for quantizing with given codebook
113 * @return quantization distortion
115 static av_always_inline float quantize_and_encode_band_cost_template(
116 struct AACEncContext *s,
117 PutBitContext *pb, const float *in,
118 const float *scaled, int size, int scale_idx,
119 int cb, const float lambda, const float uplim,
120 int *bits, int BT_ZERO, int BT_UNSIGNED,
121 int BT_PAIR, int BT_ESC, int BT_NOISE)
123 const int q_idx = POW_SF2_ZERO - scale_idx + SCALE_ONE_POS - SCALE_DIV_512;
124 const float Q = ff_aac_pow2sf_tab [q_idx];
125 const float Q34 = ff_aac_pow34sf_tab[q_idx];
126 const float IQ = ff_aac_pow2sf_tab [POW_SF2_ZERO + scale_idx - SCALE_ONE_POS + SCALE_DIV_512];
127 const float CLIPPED_ESCAPE = 165140.0f*IQ;
130 const int dim = BT_PAIR ? 2 : 4;
135 for (i = 0; i < size; i++)
139 return cost * lambda;
142 for (i = 0; i < size; i++)
146 return cost * lambda;
149 abs_pow34_v(s->scoefs, in, size);
152 quantize_bands(s->qcoefs, in, scaled, size, Q34, !BT_UNSIGNED, aac_cb_maxval[cb]);
156 off = aac_cb_maxval[cb];
158 for (i = 0; i < size; i += dim) {
160 int *quants = s->qcoefs + i;
164 for (j = 0; j < dim; j++) {
165 curidx *= aac_cb_range[cb];
166 curidx += quants[j] + off;
168 curbits = ff_aac_spectral_bits[cb-1][curidx];
169 vec = &ff_aac_codebook_vectors[cb-1][curidx*dim];
171 for (j = 0; j < dim; j++) {
172 float t = fabsf(in[i+j]);
174 if (BT_ESC && vec[j] == 64.0f) { //FIXME: slow
175 if (t >= CLIPPED_ESCAPE) {
176 di = t - CLIPPED_ESCAPE;
179 int c = av_clip_uintp2(quant(t, Q), 13);
180 di = t - c*cbrtf(c)*IQ;
181 curbits += av_log2(c)*2 - 4 + 1;
191 for (j = 0; j < dim; j++) {
192 float di = in[i+j] - vec[j]*IQ;
196 cost += rd * lambda + curbits;
201 put_bits(pb, ff_aac_spectral_bits[cb-1][curidx], ff_aac_spectral_codes[cb-1][curidx]);
203 for (j = 0; j < dim; j++)
204 if (ff_aac_codebook_vectors[cb-1][curidx*dim+j] != 0.0f)
205 put_bits(pb, 1, in[i+j] < 0.0f);
207 for (j = 0; j < 2; j++) {
208 if (ff_aac_codebook_vectors[cb-1][curidx*2+j] == 64.0f) {
209 int coef = av_clip_uintp2(quant(fabsf(in[i+j]), Q), 13);
210 int len = av_log2(coef);
212 put_bits(pb, len - 4 + 1, (1 << (len - 4 + 1)) - 2);
213 put_sbits(pb, len, coef);
225 static float quantize_and_encode_band_cost_NONE(struct AACEncContext *s, PutBitContext *pb,
226 const float *in, const float *scaled,
227 int size, int scale_idx, int cb,
228 const float lambda, const float uplim,
234 #define QUANTIZE_AND_ENCODE_BAND_COST_FUNC(NAME, BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC, BT_NOISE) \
235 static float quantize_and_encode_band_cost_ ## NAME( \
236 struct AACEncContext *s, \
237 PutBitContext *pb, const float *in, \
238 const float *scaled, int size, int scale_idx, \
239 int cb, const float lambda, const float uplim, \
241 return quantize_and_encode_band_cost_template( \
242 s, pb, in, scaled, size, scale_idx, \
243 BT_ESC ? ESC_BT : cb, lambda, uplim, bits, \
244 BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC, BT_NOISE); \
247 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ZERO, 1, 0, 0, 0, 0)
248 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SQUAD, 0, 0, 0, 0, 0)
249 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UQUAD, 0, 1, 0, 0, 0)
250 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SPAIR, 0, 0, 1, 0, 0)
251 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UPAIR, 0, 1, 1, 0, 0)
252 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ESC, 0, 1, 1, 1, 0)
253 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(NOISE, 0, 0, 0, 0, 1)
255 static float (*const quantize_and_encode_band_cost_arr[])(
256 struct AACEncContext *s,
257 PutBitContext *pb, const float *in,
258 const float *scaled, int size, int scale_idx,
259 int cb, const float lambda, const float uplim,
261 quantize_and_encode_band_cost_ZERO,
262 quantize_and_encode_band_cost_SQUAD,
263 quantize_and_encode_band_cost_SQUAD,
264 quantize_and_encode_band_cost_UQUAD,
265 quantize_and_encode_band_cost_UQUAD,
266 quantize_and_encode_band_cost_SPAIR,
267 quantize_and_encode_band_cost_SPAIR,
268 quantize_and_encode_band_cost_UPAIR,
269 quantize_and_encode_band_cost_UPAIR,
270 quantize_and_encode_band_cost_UPAIR,
271 quantize_and_encode_band_cost_UPAIR,
272 quantize_and_encode_band_cost_ESC,
273 quantize_and_encode_band_cost_NONE, /* CB 12 doesn't exist */
274 quantize_and_encode_band_cost_NOISE,
277 #define quantize_and_encode_band_cost( \
278 s, pb, in, scaled, size, scale_idx, cb, \
279 lambda, uplim, bits) \
280 quantize_and_encode_band_cost_arr[cb]( \
281 s, pb, in, scaled, size, scale_idx, cb, \
284 static float quantize_band_cost(struct AACEncContext *s, const float *in,
285 const float *scaled, int size, int scale_idx,
286 int cb, const float lambda, const float uplim,
289 return quantize_and_encode_band_cost(s, NULL, in, scaled, size, scale_idx,
290 cb, lambda, uplim, bits);
293 static void quantize_and_encode_band(struct AACEncContext *s, PutBitContext *pb,
294 const float *in, int size, int scale_idx,
295 int cb, const float lambda)
297 quantize_and_encode_band_cost(s, pb, in, NULL, size, scale_idx, cb, lambda,
301 static float find_max_val(int group_len, int swb_size, const float *scaled) {
304 for (w2 = 0; w2 < group_len; w2++) {
305 for (i = 0; i < swb_size; i++) {
306 maxval = FFMAX(maxval, scaled[w2*128+i]);
312 static int find_min_book(float maxval, int sf) {
313 float Q = ff_aac_pow2sf_tab[POW_SF2_ZERO - sf + SCALE_ONE_POS - SCALE_DIV_512];
314 float Q34 = sqrtf(Q * sqrtf(Q));
316 qmaxval = maxval * Q34 + 0.4054f;
317 if (qmaxval == 0) cb = 0;
318 else if (qmaxval == 1) cb = 1;
319 else if (qmaxval == 2) cb = 3;
320 else if (qmaxval <= 4) cb = 5;
321 else if (qmaxval <= 7) cb = 7;
322 else if (qmaxval <= 12) cb = 9;
328 * structure used in optimal codebook search
330 typedef struct BandCodingPath {
331 int prev_idx; ///< pointer to the previous path point
332 float cost; ///< path cost
337 * Encode band info for single window group bands.
339 static void encode_window_bands_info(AACEncContext *s, SingleChannelElement *sce,
340 int win, int group_len, const float lambda)
342 BandCodingPath path[120][CB_TOT];
343 int w, swb, cb, start, size;
345 const int max_sfb = sce->ics.max_sfb;
346 const int run_bits = sce->ics.num_windows == 1 ? 5 : 3;
347 const int run_esc = (1 << run_bits) - 1;
348 int idx, ppos, count;
349 int stackrun[120], stackcb[120], stack_len;
350 float next_minrd = INFINITY;
353 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
355 for (cb = 0; cb < CB_TOT; cb++) {
356 path[0][cb].cost = 0.0f;
357 path[0][cb].prev_idx = -1;
360 for (swb = 0; swb < max_sfb; swb++) {
361 size = sce->ics.swb_sizes[swb];
362 if (sce->zeroes[win*16 + swb]) {
363 for (cb = 0; cb < CB_TOT; cb++) {
364 path[swb+1][cb].prev_idx = cb;
365 path[swb+1][cb].cost = path[swb][cb].cost;
366 path[swb+1][cb].run = path[swb][cb].run + 1;
369 float minrd = next_minrd;
370 int mincb = next_mincb;
371 next_minrd = INFINITY;
373 for (cb = 0; cb < CB_TOT; cb++) {
374 float cost_stay_here, cost_get_here;
376 for (w = 0; w < group_len; w++) {
377 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(win+w)*16+swb];
378 rd += quantize_band_cost(s, sce->coeffs + start + w*128,
379 s->scoefs + start + w*128, size,
380 sce->sf_idx[(win+w)*16+swb], aac_cb_out_map[cb],
381 lambda / band->threshold, INFINITY, NULL);
383 cost_stay_here = path[swb][cb].cost + rd;
384 cost_get_here = minrd + rd + run_bits + 4;
385 if ( run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run]
386 != run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1])
387 cost_stay_here += run_bits;
388 if (cost_get_here < cost_stay_here) {
389 path[swb+1][cb].prev_idx = mincb;
390 path[swb+1][cb].cost = cost_get_here;
391 path[swb+1][cb].run = 1;
393 path[swb+1][cb].prev_idx = cb;
394 path[swb+1][cb].cost = cost_stay_here;
395 path[swb+1][cb].run = path[swb][cb].run + 1;
397 if (path[swb+1][cb].cost < next_minrd) {
398 next_minrd = path[swb+1][cb].cost;
403 start += sce->ics.swb_sizes[swb];
406 //convert resulting path from backward-linked list
409 for (cb = 1; cb < CB_TOT; cb++)
410 if (path[max_sfb][cb].cost < path[max_sfb][idx].cost)
415 stackrun[stack_len] = path[ppos][cb].run;
416 stackcb [stack_len] = cb;
417 idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx;
418 ppos -= path[ppos][cb].run;
421 //perform actual band info encoding
423 for (i = stack_len - 1; i >= 0; i--) {
424 cb = aac_cb_out_map[stackcb[i]];
425 put_bits(&s->pb, 4, cb);
427 memset(sce->zeroes + win*16 + start, !cb, count);
428 //XXX: memset when band_type is also uint8_t
429 for (j = 0; j < count; j++) {
430 sce->band_type[win*16 + start] = cb;
433 while (count >= run_esc) {
434 put_bits(&s->pb, run_bits, run_esc);
437 put_bits(&s->pb, run_bits, count);
441 static void codebook_trellis_rate(AACEncContext *s, SingleChannelElement *sce,
442 int win, int group_len, const float lambda)
444 BandCodingPath path[120][CB_TOT];
445 int w, swb, cb, start, size;
447 const int max_sfb = sce->ics.max_sfb;
448 const int run_bits = sce->ics.num_windows == 1 ? 5 : 3;
449 const int run_esc = (1 << run_bits) - 1;
450 int idx, ppos, count;
451 int stackrun[120], stackcb[120], stack_len;
452 float next_minbits = INFINITY;
455 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
457 for (cb = 0; cb < CB_TOT; cb++) {
458 path[0][cb].cost = run_bits+4;
459 path[0][cb].prev_idx = -1;
462 for (swb = 0; swb < max_sfb; swb++) {
463 size = sce->ics.swb_sizes[swb];
464 if (sce->zeroes[win*16 + swb]) {
465 float cost_stay_here = path[swb][0].cost;
466 float cost_get_here = next_minbits + run_bits + 4;
467 if ( run_value_bits[sce->ics.num_windows == 8][path[swb][0].run]
468 != run_value_bits[sce->ics.num_windows == 8][path[swb][0].run+1])
469 cost_stay_here += run_bits;
470 if (cost_get_here < cost_stay_here) {
471 path[swb+1][0].prev_idx = next_mincb;
472 path[swb+1][0].cost = cost_get_here;
473 path[swb+1][0].run = 1;
475 path[swb+1][0].prev_idx = 0;
476 path[swb+1][0].cost = cost_stay_here;
477 path[swb+1][0].run = path[swb][0].run + 1;
479 next_minbits = path[swb+1][0].cost;
481 for (cb = 1; cb < CB_TOT; cb++) {
482 path[swb+1][cb].cost = 61450;
483 path[swb+1][cb].prev_idx = -1;
484 path[swb+1][cb].run = 0;
487 float minbits = next_minbits;
488 int mincb = next_mincb;
489 int startcb = sce->band_type[win*16+swb];
490 startcb = aac_cb_in_map[startcb];
491 next_minbits = INFINITY;
493 for (cb = 0; cb < startcb; cb++) {
494 path[swb+1][cb].cost = 61450;
495 path[swb+1][cb].prev_idx = -1;
496 path[swb+1][cb].run = 0;
498 for (cb = startcb; cb < CB_TOT; cb++) {
499 float cost_stay_here, cost_get_here;
501 if (cb == 12 && sce->band_type[win*16+swb] != NOISE_BT) {
502 path[swb+1][cb].cost = 61450;
503 path[swb+1][cb].prev_idx = -1;
504 path[swb+1][cb].run = 0;
507 for (w = 0; w < group_len; w++) {
508 bits += quantize_band_cost(s, sce->coeffs + start + w*128,
509 s->scoefs + start + w*128, size,
510 sce->sf_idx[(win+w)*16+swb],
514 cost_stay_here = path[swb][cb].cost + bits;
515 cost_get_here = minbits + bits + run_bits + 4;
516 if ( run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run]
517 != run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1])
518 cost_stay_here += run_bits;
519 if (cost_get_here < cost_stay_here) {
520 path[swb+1][cb].prev_idx = mincb;
521 path[swb+1][cb].cost = cost_get_here;
522 path[swb+1][cb].run = 1;
524 path[swb+1][cb].prev_idx = cb;
525 path[swb+1][cb].cost = cost_stay_here;
526 path[swb+1][cb].run = path[swb][cb].run + 1;
528 if (path[swb+1][cb].cost < next_minbits) {
529 next_minbits = path[swb+1][cb].cost;
534 start += sce->ics.swb_sizes[swb];
537 //convert resulting path from backward-linked list
540 for (cb = 1; cb < CB_TOT; cb++)
541 if (path[max_sfb][cb].cost < path[max_sfb][idx].cost)
545 av_assert1(idx >= 0);
547 stackrun[stack_len] = path[ppos][cb].run;
548 stackcb [stack_len] = cb;
549 idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx;
550 ppos -= path[ppos][cb].run;
553 //perform actual band info encoding
555 for (i = stack_len - 1; i >= 0; i--) {
556 cb = aac_cb_out_map[stackcb[i]];
557 put_bits(&s->pb, 4, cb);
559 memset(sce->zeroes + win*16 + start, !cb, count);
560 //XXX: memset when band_type is also uint8_t
561 for (j = 0; j < count; j++) {
562 sce->band_type[win*16 + start] = cb;
565 while (count >= run_esc) {
566 put_bits(&s->pb, run_bits, run_esc);
569 put_bits(&s->pb, run_bits, count);
573 /** Return the minimum scalefactor where the quantized coef does not clip. */
574 static av_always_inline uint8_t coef2minsf(float coef) {
575 return av_clip_uint8(log2f(coef)*4 - 69 + SCALE_ONE_POS - SCALE_DIV_512);
578 /** Return the maximum scalefactor where the quantized coef is not zero. */
579 static av_always_inline uint8_t coef2maxsf(float coef) {
580 return av_clip_uint8(log2f(coef)*4 + 6 + SCALE_ONE_POS - SCALE_DIV_512);
583 typedef struct TrellisPath {
588 #define TRELLIS_STAGES 121
589 #define TRELLIS_STATES (SCALE_MAX_DIFF+1)
591 static void search_for_quantizers_anmr(AVCodecContext *avctx, AACEncContext *s,
592 SingleChannelElement *sce,
595 int q, w, w2, g, start = 0;
598 TrellisPath paths[TRELLIS_STAGES][TRELLIS_STATES];
599 int bandaddr[TRELLIS_STAGES];
602 float q0f = FLT_MAX, q1f = 0.0f, qnrgf = 0.0f;
603 int q0, q1, qcnt = 0;
605 for (i = 0; i < 1024; i++) {
606 float t = fabsf(sce->coeffs[i]);
616 memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
617 memset(sce->zeroes, 1, sizeof(sce->zeroes));
621 //minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped
622 q0 = coef2minsf(q0f);
623 //maximum scalefactor index is when maximum coefficient after quantizing is still not zero
624 q1 = coef2maxsf(q1f);
628 //minimum scalefactor index is when maximum nonzero coefficient after quantizing is not clipped
629 int qnrg = av_clip_uint8(log2f(sqrtf(qnrgf/qcnt))*4 - 31 + SCALE_ONE_POS - SCALE_DIV_512);
635 } else if (q1 > q1high) {
641 for (i = 0; i < TRELLIS_STATES; i++) {
642 paths[0][i].cost = 0.0f;
643 paths[0][i].prev = -1;
645 for (j = 1; j < TRELLIS_STAGES; j++) {
646 for (i = 0; i < TRELLIS_STATES; i++) {
647 paths[j][i].cost = INFINITY;
648 paths[j][i].prev = -2;
652 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
653 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
655 for (g = 0; g < sce->ics.num_swb; g++) {
656 const float *coefs = sce->coeffs + start;
660 bandaddr[idx] = w * 16 + g;
663 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
664 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
665 if (band->energy <= band->threshold || band->threshold == 0.0f) {
666 sce->zeroes[(w+w2)*16+g] = 1;
669 sce->zeroes[(w+w2)*16+g] = 0;
671 for (i = 0; i < sce->ics.swb_sizes[g]; i++) {
672 float t = fabsf(coefs[w2*128+i]);
674 qmin = FFMIN(qmin, t);
675 qmax = FFMAX(qmax, t);
679 int minscale, maxscale;
680 float minrd = INFINITY;
682 //minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped
683 minscale = coef2minsf(qmin);
684 //maximum scalefactor index is when maximum coefficient after quantizing is still not zero
685 maxscale = coef2maxsf(qmax);
686 minscale = av_clip(minscale - q0, 0, TRELLIS_STATES - 1);
687 maxscale = av_clip(maxscale - q0, 0, TRELLIS_STATES);
688 maxval = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], s->scoefs+start);
689 for (q = minscale; q < maxscale; q++) {
691 int cb = find_min_book(maxval, sce->sf_idx[w*16+g]);
692 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
693 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
694 dist += quantize_band_cost(s, coefs + w2*128, s->scoefs + start + w2*128, sce->ics.swb_sizes[g],
695 q + q0, cb, lambda / band->threshold, INFINITY, NULL);
697 minrd = FFMIN(minrd, dist);
699 for (i = 0; i < q1 - q0; i++) {
701 cost = paths[idx - 1][i].cost + dist
702 + ff_aac_scalefactor_bits[q - i + SCALE_DIFF_ZERO];
703 if (cost < paths[idx][q].cost) {
704 paths[idx][q].cost = cost;
705 paths[idx][q].prev = i;
710 for (q = 0; q < q1 - q0; q++) {
711 paths[idx][q].cost = paths[idx - 1][q].cost + 1;
712 paths[idx][q].prev = q;
715 sce->zeroes[w*16+g] = !nz;
716 start += sce->ics.swb_sizes[g];
721 mincost = paths[idx][0].cost;
723 for (i = 1; i < TRELLIS_STATES; i++) {
724 if (paths[idx][i].cost < mincost) {
725 mincost = paths[idx][i].cost;
730 sce->sf_idx[bandaddr[idx]] = minq + q0;
731 minq = paths[idx][minq].prev;
734 //set the same quantizers inside window groups
735 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
736 for (g = 0; g < sce->ics.num_swb; g++)
737 for (w2 = 1; w2 < sce->ics.group_len[w]; w2++)
738 sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g];
742 * two-loop quantizers search taken from ISO 13818-7 Appendix C
744 static void search_for_quantizers_twoloop(AVCodecContext *avctx,
746 SingleChannelElement *sce,
749 int start = 0, i, w, w2, g;
750 int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->channels * (lambda / 120.f);
751 const float freq_mult = avctx->sample_rate/(1024.0f/sce->ics.num_windows)/2.0f;
752 float dists[128] = { 0 }, uplims[128] = { 0 };
754 int noise_sf[128] = { 0 };
755 int fflag, minscaler, minscaler_n;
758 float minthr = INFINITY;
760 // for values above this the decoder might end up in an endless loop
761 // due to always having more bits than what can be encoded.
762 destbits = FFMIN(destbits, 5800);
763 //XXX: some heuristic to determine initial quantizers will reduce search time
764 //determine zero bands and upper limits
765 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
767 for (g = 0; g < sce->ics.num_swb; g++) {
769 float uplim = 0.0f, energy = 0.0f;
770 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
771 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
772 uplim += band->threshold;
773 energy += band->energy;
774 if (band->energy <= band->threshold || band->threshold == 0.0f) {
775 sce->zeroes[(w+w2)*16+g] = 1;
780 uplims[w*16+g] = uplim *512;
781 if (s->options.pns && start*freq_mult > NOISE_LOW_LIMIT && energy < uplim * 1.2f) {
782 noise_sf[w*16+g] = av_clip(4+FFMIN(log2f(energy)*2,255), -100, 155);
783 sce->band_type[w*16+g] = NOISE_BT;
785 } else { /** Band type will be determined by the twoloop algorithm */
786 sce->band_type[w*16+g] = 0;
788 sce->zeroes[w*16+g] = !nz;
790 minthr = FFMIN(minthr, uplim);
792 start += sce->ics.swb_sizes[g];
795 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
796 for (g = 0; g < sce->ics.num_swb; g++) {
797 if (sce->zeroes[w*16+g]) {
798 sce->sf_idx[w*16+g] = SCALE_ONE_POS;
801 sce->sf_idx[w*16+g] = SCALE_ONE_POS + FFMIN(log2f(uplims[w*16+g]/minthr)*4,59);
807 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
809 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
811 for (g = 0; g < sce->ics.num_swb; g++) {
812 const float *scaled = s->scoefs + start;
813 maxvals[w*16+g] = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], scaled);
814 start += sce->ics.swb_sizes[g];
818 //perform two-loop search
819 //outer loop - improve quality
822 minscaler = sce->sf_idx[0];
823 minscaler_n = sce->sf_idx[0];
824 //inner loop - quantize spectrum to fit into given number of bits
825 qstep = its ? 1 : 32;
829 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
831 for (g = 0; g < sce->ics.num_swb; g++) {
832 const float *coefs = sce->coeffs + start;
833 const float *scaled = s->scoefs + start;
838 if (sce->band_type[w*16+g] == NOISE_BT) {
839 minscaler_n = FFMIN(minscaler_n, noise_sf[w*16+g]);
840 start += sce->ics.swb_sizes[g];
842 } else if (sce->zeroes[w*16+g] || sce->sf_idx[w*16+g] >= 218) {
843 start += sce->ics.swb_sizes[g];
846 minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]);
847 cb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]);
848 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
850 dist += quantize_band_cost(s, coefs + w2*128,
852 sce->ics.swb_sizes[g],
860 dists[w*16+g] = dist - bits;
862 bits += ff_aac_scalefactor_bits[sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO];
865 start += sce->ics.swb_sizes[g];
866 prev = sce->sf_idx[w*16+g];
869 if (tbits > destbits) {
870 for (i = 0; i < 128; i++)
871 if (sce->sf_idx[i] < 218 - qstep)
872 sce->sf_idx[i] += qstep;
874 for (i = 0; i < 128; i++)
875 if (sce->sf_idx[i] > 60 - qstep)
876 sce->sf_idx[i] -= qstep;
879 if (!qstep && tbits > destbits*1.02 && sce->sf_idx[0] < 217)
884 minscaler = av_clip(minscaler, 60, 255 - SCALE_MAX_DIFF);
886 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
887 for (g = 0; g < sce->ics.num_swb; g++)
888 if (sce->band_type[w*16+g] == NOISE_BT)
889 sce->sf_idx[w*16+g] = av_clip(noise_sf[w*16+g], minscaler_n, minscaler_n + SCALE_MAX_DIFF);
891 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
892 for (g = 0; g < sce->ics.num_swb; g++) {
893 int prevsc = sce->sf_idx[w*16+g];
894 if (sce->band_type[w*16+g] == NOISE_BT)
896 if (dists[w*16+g] > uplims[w*16+g] && sce->sf_idx[w*16+g] > 60) {
897 if (find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]-1))
898 sce->sf_idx[w*16+g]--;
899 else //Try to make sure there is some energy in every band
900 sce->sf_idx[w*16+g]-=2;
902 sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], minscaler, minscaler + SCALE_MAX_DIFF);
903 sce->sf_idx[w*16+g] = FFMIN(sce->sf_idx[w*16+g], 219);
904 if (sce->sf_idx[w*16+g] != prevsc)
906 sce->band_type[w*16+g] = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]);
910 } while (fflag && its < 10);
913 static void search_for_quantizers_faac(AVCodecContext *avctx, AACEncContext *s,
914 SingleChannelElement *sce,
917 int start = 0, i, w, w2, g;
918 float uplim[128], maxq[128];
920 float distfact = ((sce->ics.num_windows > 1) ? 85.80 : 147.84) / lambda;
921 int last = 0, lastband = 0, curband = 0;
922 float avg_energy = 0.0;
923 if (sce->ics.num_windows == 1) {
925 for (i = 0; i < 1024; i++) {
926 if (i - start >= sce->ics.swb_sizes[curband]) {
927 start += sce->ics.swb_sizes[curband];
930 if (sce->coeffs[i]) {
931 avg_energy += sce->coeffs[i] * sce->coeffs[i];
937 for (w = 0; w < 8; w++) {
938 const float *coeffs = sce->coeffs + w*128;
940 for (i = 0; i < 128; i++) {
941 if (i - start >= sce->ics.swb_sizes[curband]) {
942 start += sce->ics.swb_sizes[curband];
946 avg_energy += coeffs[i] * coeffs[i];
947 last = FFMAX(last, i);
948 lastband = FFMAX(lastband, curband);
955 if (avg_energy == 0.0f) {
956 for (i = 0; i < FF_ARRAY_ELEMS(sce->sf_idx); i++)
957 sce->sf_idx[i] = SCALE_ONE_POS;
960 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
962 for (g = 0; g < sce->ics.num_swb; g++) {
963 float *coefs = sce->coeffs + start;
964 const int size = sce->ics.swb_sizes[g];
965 int start2 = start, end2 = start + size, peakpos = start;
966 float maxval = -1, thr = 0.0f, t;
971 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++)
972 memset(coefs + w2*128, 0, sizeof(coefs[0])*size);
975 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
976 for (i = 0; i < size; i++) {
977 float t = coefs[w2*128+i]*coefs[w2*128+i];
978 maxq[w*16+g] = FFMAX(maxq[w*16+g], fabsf(coefs[w2*128 + i]));
980 if (sce->ics.num_windows == 1 && maxval < t) {
986 if (sce->ics.num_windows == 1) {
987 start2 = FFMAX(peakpos - 2, start2);
988 end2 = FFMIN(peakpos + 3, end2);
994 thr = pow(thr / (avg_energy * (end2 - start2)), 0.3 + 0.1*(lastband - g) / lastband);
995 t = 1.0 - (1.0 * start2 / last);
996 uplim[w*16+g] = distfact / (1.4 * thr + t*t*t + 0.075);
999 memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
1000 abs_pow34_v(s->scoefs, sce->coeffs, 1024);
1001 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
1003 for (g = 0; g < sce->ics.num_swb; g++) {
1004 const float *coefs = sce->coeffs + start;
1005 const float *scaled = s->scoefs + start;
1006 const int size = sce->ics.swb_sizes[g];
1007 int scf, prev_scf, step;
1008 int min_scf = -1, max_scf = 256;
1010 if (maxq[w*16+g] < 21.544) {
1011 sce->zeroes[w*16+g] = 1;
1015 sce->zeroes[w*16+g] = 0;
1016 scf = prev_scf = av_clip(SCALE_ONE_POS - SCALE_DIV_512 - log2f(1/maxq[w*16+g])*16/3, 60, 218);
1021 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
1023 dist += quantize_band_cost(s, coefs + w2*128,
1025 sce->ics.swb_sizes[g],
1033 dist *= 1.0f / 512.0f / lambda;
1034 quant_max = quant(maxq[w*16+g], ff_aac_pow2sf_tab[POW_SF2_ZERO - scf + SCALE_ONE_POS - SCALE_DIV_512]);
1035 if (quant_max >= 8191) { // too much, return to the previous quantizer
1036 sce->sf_idx[w*16+g] = prev_scf;
1040 curdiff = fabsf(dist - uplim[w*16+g]);
1041 if (curdiff <= 1.0f)
1044 step = log2f(curdiff);
1045 if (dist > uplim[w*16+g])
1048 scf = av_clip_uint8(scf);
1049 step = scf - prev_scf;
1050 if (FFABS(step) <= 1 || (step > 0 && scf >= max_scf) || (step < 0 && scf <= min_scf)) {
1051 sce->sf_idx[w*16+g] = av_clip(scf, min_scf, max_scf);
1062 minq = sce->sf_idx[0] ? sce->sf_idx[0] : INT_MAX;
1063 for (i = 1; i < 128; i++) {
1064 if (!sce->sf_idx[i])
1065 sce->sf_idx[i] = sce->sf_idx[i-1];
1067 minq = FFMIN(minq, sce->sf_idx[i]);
1069 if (minq == INT_MAX)
1071 minq = FFMIN(minq, SCALE_MAX_POS);
1072 maxsf = FFMIN(minq + SCALE_MAX_DIFF, SCALE_MAX_POS);
1073 for (i = 126; i >= 0; i--) {
1074 if (!sce->sf_idx[i])
1075 sce->sf_idx[i] = sce->sf_idx[i+1];
1076 sce->sf_idx[i] = av_clip(sce->sf_idx[i], minq, maxsf);
1080 static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s,
1081 SingleChannelElement *sce,
1087 memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
1088 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
1089 for (g = 0; g < sce->ics.num_swb; g++) {
1090 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
1091 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
1092 if (band->energy <= band->threshold) {
1093 sce->sf_idx[(w+w2)*16+g] = 218;
1094 sce->zeroes[(w+w2)*16+g] = 1;
1096 sce->sf_idx[(w+w2)*16+g] = av_clip(SCALE_ONE_POS - SCALE_DIV_512 + log2f(band->threshold), 80, 218);
1097 sce->zeroes[(w+w2)*16+g] = 0;
1099 minq = FFMIN(minq, sce->sf_idx[(w+w2)*16+g]);
1103 for (i = 0; i < 128; i++) {
1104 sce->sf_idx[i] = 140;
1105 //av_clip(sce->sf_idx[i], minq, minq + SCALE_MAX_DIFF - 1);
1107 //set the same quantizers inside window groups
1108 for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
1109 for (g = 0; g < sce->ics.num_swb; g++)
1110 for (w2 = 1; w2 < sce->ics.group_len[w]; w2++)
1111 sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g];
1114 static void search_for_ms(AACEncContext *s, ChannelElement *cpe,
1117 int start = 0, i, w, w2, g;
1118 float M[128], S[128];
1119 float *L34 = s->scoefs, *R34 = s->scoefs + 128, *M34 = s->scoefs + 128*2, *S34 = s->scoefs + 128*3;
1120 SingleChannelElement *sce0 = &cpe->ch[0];
1121 SingleChannelElement *sce1 = &cpe->ch[1];
1122 if (!cpe->common_window)
1124 for (w = 0; w < sce0->ics.num_windows; w += sce0->ics.group_len[w]) {
1125 for (g = 0; g < sce0->ics.num_swb; g++) {
1126 if (!cpe->ch[0].zeroes[w*16+g] && !cpe->ch[1].zeroes[w*16+g]) {
1127 float dist1 = 0.0f, dist2 = 0.0f;
1128 for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) {
1129 FFPsyBand *band0 = &s->psy.ch[s->cur_channel+0].psy_bands[(w+w2)*16+g];
1130 FFPsyBand *band1 = &s->psy.ch[s->cur_channel+1].psy_bands[(w+w2)*16+g];
1131 float minthr = FFMIN(band0->threshold, band1->threshold);
1132 float maxthr = FFMAX(band0->threshold, band1->threshold);
1133 for (i = 0; i < sce0->ics.swb_sizes[g]; i++) {
1134 M[i] = (sce0->pcoeffs[start+w2*128+i]
1135 + sce1->pcoeffs[start+w2*128+i]) * 0.5;
1137 - sce1->pcoeffs[start+w2*128+i];
1139 abs_pow34_v(L34, sce0->coeffs+start+w2*128, sce0->ics.swb_sizes[g]);
1140 abs_pow34_v(R34, sce1->coeffs+start+w2*128, sce0->ics.swb_sizes[g]);
1141 abs_pow34_v(M34, M, sce0->ics.swb_sizes[g]);
1142 abs_pow34_v(S34, S, sce0->ics.swb_sizes[g]);
1143 dist1 += quantize_band_cost(s, sce0->coeffs + start + w2*128,
1145 sce0->ics.swb_sizes[g],
1146 sce0->sf_idx[(w+w2)*16+g],
1147 sce0->band_type[(w+w2)*16+g],
1148 lambda / band0->threshold, INFINITY, NULL);
1149 dist1 += quantize_band_cost(s, sce1->coeffs + start + w2*128,
1151 sce1->ics.swb_sizes[g],
1152 sce1->sf_idx[(w+w2)*16+g],
1153 sce1->band_type[(w+w2)*16+g],
1154 lambda / band1->threshold, INFINITY, NULL);
1155 dist2 += quantize_band_cost(s, M,
1157 sce0->ics.swb_sizes[g],
1158 sce0->sf_idx[(w+w2)*16+g],
1159 sce0->band_type[(w+w2)*16+g],
1160 lambda / maxthr, INFINITY, NULL);
1161 dist2 += quantize_band_cost(s, S,
1163 sce1->ics.swb_sizes[g],
1164 sce1->sf_idx[(w+w2)*16+g],
1165 sce1->band_type[(w+w2)*16+g],
1166 lambda / minthr, INFINITY, NULL);
1168 cpe->ms_mask[w*16+g] = dist2 < dist1;
1170 start += sce0->ics.swb_sizes[g];
1175 AACCoefficientsEncoder ff_aac_coders[AAC_CODER_NB] = {
1176 [AAC_CODER_FAAC] = {
1177 search_for_quantizers_faac,
1178 encode_window_bands_info,
1179 quantize_and_encode_band,
1182 [AAC_CODER_ANMR] = {
1183 search_for_quantizers_anmr,
1184 encode_window_bands_info,
1185 quantize_and_encode_band,
1188 [AAC_CODER_TWOLOOP] = {
1189 search_for_quantizers_twoloop,
1190 codebook_trellis_rate,
1191 quantize_and_encode_band,
1194 [AAC_CODER_FAST] = {
1195 search_for_quantizers_fast,
1196 encode_window_bands_info,
1197 quantize_and_encode_band,