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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 #include "libavutil/mathematics.h"
  37 #include "avcodec.h"
  38 #include "put_bits.h"
  39 #include "aac.h"
  40 #include "aacenc.h"
  41 #include "aactab.h"
  42
  43 /** bits needed to code codebook run value for long windows */
  44 static const uint8_t run_value_bits_long[64] = {
  45      5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,
  46      5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5,  5, 10,
  47     10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
  48     10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 15
  49 };
  50
  51 /** bits needed to code codebook run value for short windows */
  52 static const uint8_t run_value_bits_short[16] = {
  53     3, 3, 3, 3, 3, 3, 3, 6, 6, 6, 6, 6, 6, 6, 6, 9
  54 };
  55
  56 static const uint8_t *run_value_bits[2] = {
  57     run_value_bits_long, run_value_bits_short
  58 };
  59
  60
  61 /**
  62  * Quantize one coefficient.
  63  * @return absolute value of the quantized coefficient
  64  * @see 3GPP TS26.403 5.6.2 "Scalefactor determination"
  65  */
  66 static av_always_inline int quant(float coef, const float Q)
  67 {
  68     float a = coef * Q;
  69     return sqrtf(a * sqrtf(a)) + 0.4054;
  70 }
  71
  72 static void quantize_bands(int *out, const float *in, const float *scaled,
  73                            int size, float Q34, int is_signed, int maxval)
  74 {
  75     int i;
  76     double qc;
  77     for (i = 0; i < size; i++) {
  78         qc = scaled[i] * Q34;
  79         out[i] = (int)FFMIN(qc + 0.4054, (double)maxval);
  80         if (is_signed && in[i] < 0.0f) {
  81             out[i] = -out[i];
  82         }
  83     }
  84 }
  85
  86 static void abs_pow34_v(float *out, const float *in, const int size)
  87 {
  88 #ifndef USE_REALLY_FULL_SEARCH
  89     int i;
  90     for (i = 0; i < size; i++) {
  91         float a = fabsf(in[i]);
  92         out[i] = sqrtf(a * sqrtf(a));
  93     }
  94 #endif /* USE_REALLY_FULL_SEARCH */
  95 }
  96
  97 static const uint8_t aac_cb_range [12] = {0, 3, 3, 3, 3, 9, 9, 8, 8, 13, 13, 17};
  98 static const uint8_t aac_cb_maxval[12] = {0, 1, 1, 2, 2, 4, 4, 7, 7, 12, 12, 16};
  99
 100 /**
 101  * Calculate rate distortion cost for quantizing with given codebook
 102  *
 103  * @return quantization distortion
 104  */
 105 static av_always_inline float quantize_and_encode_band_cost_template(
 106                                 struct AACEncContext *s,
 107                                 PutBitContext *pb, const float *in,
 108                                 const float *scaled, int size, int scale_idx,
 109                                 int cb, const float lambda, const float uplim,
 110                                 int *bits, int BT_ZERO, int BT_UNSIGNED,
 111                                 int BT_PAIR, int BT_ESC)
 112 {
 113     const int q_idx = POW_SF2_ZERO - scale_idx + SCALE_ONE_POS - SCALE_DIV_512;
 114     const float Q   = ff_aac_pow2sf_tab [q_idx];
 115     const float Q34 = ff_aac_pow34sf_tab[q_idx];
 116     const float IQ  = ff_aac_pow2sf_tab [POW_SF2_ZERO + scale_idx - SCALE_ONE_POS + SCALE_DIV_512];
 117     const float CLIPPED_ESCAPE = 165140.0f*IQ;
 118     int i, j;
 119     float cost = 0;
 120     const int dim = BT_PAIR ? 2 : 4;
 121     int resbits = 0;
 122     const int range  = aac_cb_range[cb];
 123     const int maxval = aac_cb_maxval[cb];
 124     int off;
 125
 126     if (BT_ZERO) {
 127         for (i = 0; i < size; i++)
 128             cost += in[i]*in[i];
 129         if (bits)
 130             *bits = 0;
 131         return cost * lambda;
 132     }
 133     if (!scaled) {
 134         abs_pow34_v(s->scoefs, in, size);
 135         scaled = s->scoefs;
 136     }
 137     quantize_bands(s->qcoefs, in, scaled, size, Q34, !BT_UNSIGNED, maxval);
 138     if (BT_UNSIGNED) {
 139         off = 0;
 140     } else {
 141         off = maxval;
 142     }
 143     for (i = 0; i < size; i += dim) {
 144         const float *vec;
 145         int *quants = s->qcoefs + i;
 146         int curidx = 0;
 147         int curbits;
 148         float rd = 0.0f;
 149         for (j = 0; j < dim; j++) {
 150             curidx *= range;
 151             curidx += quants[j] + off;
 152         }
 153         curbits =  ff_aac_spectral_bits[cb-1][curidx];
 154         vec     = &ff_aac_codebook_vectors[cb-1][curidx*dim];
 155         if (BT_UNSIGNED) {
 156             for (j = 0; j < dim; j++) {
 157                 float t = fabsf(in[i+j]);
 158                 float di;
 159                 if (BT_ESC && vec[j] == 64.0f) { //FIXME: slow
 160                     if (t >= CLIPPED_ESCAPE) {
 161                         di = t - CLIPPED_ESCAPE;
 162                         curbits += 21;
 163                     } else {
 164                         int c = av_clip(quant(t, Q), 0, 8191);
 165                         di = t - c*cbrtf(c)*IQ;
 166                         curbits += av_log2(c)*2 - 4 + 1;
 167                     }
 168                 } else {
 169                     di = t - vec[j]*IQ;
 170                 }
 171                 if (vec[j] != 0.0f)
 172                     curbits++;
 173                 rd += di*di;
 174             }
 175         } else {
 176             for (j = 0; j < dim; j++) {
 177                 float di = in[i+j] - vec[j]*IQ;
 178                 rd += di*di;
 179             }
 180         }
 181         cost    += rd * lambda + curbits;
 182         resbits += curbits;
 183         if (cost >= uplim)
 184             return uplim;
 185         if (pb) {
 186             put_bits(pb, ff_aac_spectral_bits[cb-1][curidx], ff_aac_spectral_codes[cb-1][curidx]);
 187             if (BT_UNSIGNED)
 188                 for (j = 0; j < dim; j++)
 189                     if (ff_aac_codebook_vectors[cb-1][curidx*dim+j] != 0.0f)
 190                         put_bits(pb, 1, in[i+j] < 0.0f);
 191             if (BT_ESC) {
 192                 for (j = 0; j < 2; j++) {
 193                     if (ff_aac_codebook_vectors[cb-1][curidx*2+j] == 64.0f) {
 194                         int coef = av_clip(quant(fabsf(in[i+j]), Q), 0, 8191);
 195                         int len = av_log2(coef);
 196
 197                         put_bits(pb, len - 4 + 1, (1 << (len - 4 + 1)) - 2);
 198                         put_bits(pb, len, coef & ((1 << len) - 1));
 199                     }
 200                 }
 201             }
 202         }
 203     }
 204
 205     if (bits)
 206         *bits = resbits;
 207     return cost;
 208 }
 209
 210 #define QUANTIZE_AND_ENCODE_BAND_COST_FUNC(NAME, BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC) \
 211 static float quantize_and_encode_band_cost_ ## NAME(                                        \
 212                                 struct AACEncContext *s,                                \
 213                                 PutBitContext *pb, const float *in,                     \
 214                                 const float *scaled, int size, int scale_idx,           \
 215                                 int cb, const float lambda, const float uplim,          \
 216                                 int *bits) {                                            \
 217     return quantize_and_encode_band_cost_template(                                      \
 218                                 s, pb, in, scaled, size, scale_idx,                     \
 219                                 BT_ESC ? ESC_BT : cb, lambda, uplim, bits,              \
 220                                 BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC);                 \
 221 }
 222
 223 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ZERO,  1, 0, 0, 0)
 224 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SQUAD, 0, 0, 0, 0)
 225 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UQUAD, 0, 1, 0, 0)
 226 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SPAIR, 0, 0, 1, 0)
 227 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UPAIR, 0, 1, 1, 0)
 228 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ESC,   0, 1, 1, 1)
 229
 230 static float (*const quantize_and_encode_band_cost_arr[])(
 231                                 struct AACEncContext *s,
 232                                 PutBitContext *pb, const float *in,
 233                                 const float *scaled, int size, int scale_idx,
 234                                 int cb, const float lambda, const float uplim,
 235                                 int *bits) = {
 236     quantize_and_encode_band_cost_ZERO,
 237     quantize_and_encode_band_cost_SQUAD,
 238     quantize_and_encode_band_cost_SQUAD,
 239     quantize_and_encode_band_cost_UQUAD,
 240     quantize_and_encode_band_cost_UQUAD,
 241     quantize_and_encode_band_cost_SPAIR,
 242     quantize_and_encode_band_cost_SPAIR,
 243     quantize_and_encode_band_cost_UPAIR,
 244     quantize_and_encode_band_cost_UPAIR,
 245     quantize_and_encode_band_cost_UPAIR,
 246     quantize_and_encode_band_cost_UPAIR,
 247     quantize_and_encode_band_cost_ESC,
 248 };
 249
 250 #define quantize_and_encode_band_cost(                                  \
 251                                 s, pb, in, scaled, size, scale_idx, cb, \
 252                                 lambda, uplim, bits)                    \
 253     quantize_and_encode_band_cost_arr[cb](                              \
 254                                 s, pb, in, scaled, size, scale_idx, cb, \
 255                                 lambda, uplim, bits)
 256
 257 static float quantize_band_cost(struct AACEncContext *s, const float *in,
 258                                 const float *scaled, int size, int scale_idx,
 259                                 int cb, const float lambda, const float uplim,
 260                                 int *bits)
 261 {
 262     return quantize_and_encode_band_cost(s, NULL, in, scaled, size, scale_idx,
 263                                          cb, lambda, uplim, bits);
 264 }
 265
 266 static void quantize_and_encode_band(struct AACEncContext *s, PutBitContext *pb,
 267                                      const float *in, int size, int scale_idx,
 268                                      int cb, const float lambda)
 269 {
 270     quantize_and_encode_band_cost(s, pb, in, NULL, size, scale_idx, cb, lambda,
 271                                   INFINITY, NULL);
 272 }
 273
 274 static float find_max_val(int group_len, int swb_size, const float *scaled) {
 275     float maxval = 0.0f;
 276     int w2, i;
 277     for (w2 = 0; w2 < group_len; w2++) {
 278         for (i = 0; i < swb_size; i++) {
 279             maxval = FFMAX(maxval, scaled[w2*128+i]);
 280         }
 281     }
 282     return maxval;
 283 }
 284
 285 static int find_min_book(float maxval, int sf) {
 286     float Q = ff_aac_pow2sf_tab[POW_SF2_ZERO - sf + SCALE_ONE_POS - SCALE_DIV_512];
 287     float Q34 = sqrtf(Q * sqrtf(Q));
 288     int qmaxval, cb;
 289     qmaxval = maxval * Q34 + 0.4054f;
 290     if      (qmaxval ==  0) cb = 0;
 291     else if (qmaxval ==  1) cb = 1;
 292     else if (qmaxval ==  2) cb = 3;
 293     else if (qmaxval <=  4) cb = 5;
 294     else if (qmaxval <=  7) cb = 7;
 295     else if (qmaxval <= 12) cb = 9;
 296     else                    cb = 11;
 297     return cb;
 298 }
 299
 300 /**
 301  * structure used in optimal codebook search
 302  */
 303 typedef struct BandCodingPath {
 304     int prev_idx; ///< pointer to the previous path point
 305     float cost;   ///< path cost
 306     int run;
 307 } BandCodingPath;
 308
 309 /**
 310  * Encode band info for single window group bands.
 311  */
 312 static void encode_window_bands_info(AACEncContext *s, SingleChannelElement *sce,
 313                                      int win, int group_len, const float lambda)
 314 {
 315     BandCodingPath path[120][12];
 316     int w, swb, cb, start, size;
 317     int i, j;
 318     const int max_sfb  = sce->ics.max_sfb;
 319     const int run_bits = sce->ics.num_windows == 1 ? 5 : 3;
 320     const int run_esc  = (1 << run_bits) - 1;
 321     int idx, ppos, count;
 322     int stackrun[120], stackcb[120], stack_len;
 323     float next_minrd = INFINITY;
 324     int next_mincb = 0;
 325
 326     abs_pow34_v(s->scoefs, sce->coeffs, 1024);
 327     start = win*128;
 328     for (cb = 0; cb < 12; cb++) {
 329         path[0][cb].cost     = 0.0f;
 330         path[0][cb].prev_idx = -1;
 331         path[0][cb].run      = 0;
 332     }
 333     for (swb = 0; swb < max_sfb; swb++) {
 334         size = sce->ics.swb_sizes[swb];
 335         if (sce->zeroes[win*16 + swb]) {
 336             for (cb = 0; cb < 12; cb++) {
 337                 path[swb+1][cb].prev_idx = cb;
 338                 path[swb+1][cb].cost     = path[swb][cb].cost;
 339                 path[swb+1][cb].run      = path[swb][cb].run + 1;
 340             }
 341         } else {
 342             float minrd = next_minrd;
 343             int mincb = next_mincb;
 344             next_minrd = INFINITY;
 345             next_mincb = 0;
 346             for (cb = 0; cb < 12; cb++) {
 347                 float cost_stay_here, cost_get_here;
 348                 float rd = 0.0f;
 349                 for (w = 0; w < group_len; w++) {
 350                     FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(win+w)*16+swb];
 351                     rd += quantize_band_cost(s, sce->coeffs + start + w*128,
 352                                              s->scoefs + start + w*128, size,
 353                                              sce->sf_idx[(win+w)*16+swb], cb,
 354                                              lambda / band->threshold, INFINITY, NULL);
 355                 }
 356                 cost_stay_here = path[swb][cb].cost + rd;
 357                 cost_get_here  = minrd              + rd + run_bits + 4;
 358                 if (   run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run]
 359                     != run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1])
 360                     cost_stay_here += run_bits;
 361                 if (cost_get_here < cost_stay_here) {
 362                     path[swb+1][cb].prev_idx = mincb;
 363                     path[swb+1][cb].cost     = cost_get_here;
 364                     path[swb+1][cb].run      = 1;
 365                 } else {
 366                     path[swb+1][cb].prev_idx = cb;
 367                     path[swb+1][cb].cost     = cost_stay_here;
 368                     path[swb+1][cb].run      = path[swb][cb].run + 1;
 369                 }
 370                 if (path[swb+1][cb].cost < next_minrd) {
 371                     next_minrd = path[swb+1][cb].cost;
 372                     next_mincb = cb;
 373                 }
 374             }
 375         }
 376         start += sce->ics.swb_sizes[swb];
 377     }
 378
 379     //convert resulting path from backward-linked list
 380     stack_len = 0;
 381     idx       = 0;
 382     for (cb = 1; cb < 12; cb++)
 383         if (path[max_sfb][cb].cost < path[max_sfb][idx].cost)
 384             idx = cb;
 385     ppos = max_sfb;
 386     while (ppos > 0) {
 387         cb = idx;
 388         stackrun[stack_len] = path[ppos][cb].run;
 389         stackcb [stack_len] = cb;
 390         idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx;
 391         ppos -= path[ppos][cb].run;
 392         stack_len++;
 393     }
 394     //perform actual band info encoding
 395     start = 0;
 396     for (i = stack_len - 1; i >= 0; i--) {
 397         put_bits(&s->pb, 4, stackcb[i]);
 398         count = stackrun[i];
 399         memset(sce->zeroes + win*16 + start, !stackcb[i], count);
 400         //XXX: memset when band_type is also uint8_t
 401         for (j = 0; j < count; j++) {
 402             sce->band_type[win*16 + start] =  stackcb[i];
 403             start++;
 404         }
 405         while (count >= run_esc) {
 406             put_bits(&s->pb, run_bits, run_esc);
 407             count -= run_esc;
 408         }
 409         put_bits(&s->pb, run_bits, count);
 410     }
 411 }
 412
 413 static void codebook_trellis_rate(AACEncContext *s, SingleChannelElement *sce,
 414                                   int win, int group_len, const float lambda)
 415 {
 416     BandCodingPath path[120][12];
 417     int w, swb, cb, start, size;
 418     int i, j;
 419     const int max_sfb  = sce->ics.max_sfb;
 420     const int run_bits = sce->ics.num_windows == 1 ? 5 : 3;
 421     const int run_esc  = (1 << run_bits) - 1;
 422     int idx, ppos, count;
 423     int stackrun[120], stackcb[120], stack_len;
 424     float next_minbits = INFINITY;
 425     int next_mincb = 0;
 426
 427     abs_pow34_v(s->scoefs, sce->coeffs, 1024);
 428     start = win*128;
 429     for (cb = 0; cb < 12; cb++) {
 430         path[0][cb].cost     = run_bits+4;
 431         path[0][cb].prev_idx = -1;
 432         path[0][cb].run      = 0;
 433     }
 434     for (swb = 0; swb < max_sfb; swb++) {
 435         size = sce->ics.swb_sizes[swb];
 436         if (sce->zeroes[win*16 + swb]) {
 437             float cost_stay_here = path[swb][0].cost;
 438             float cost_get_here  = next_minbits + run_bits + 4;
 439             if (   run_value_bits[sce->ics.num_windows == 8][path[swb][0].run]
 440                 != run_value_bits[sce->ics.num_windows == 8][path[swb][0].run+1])
 441                 cost_stay_here += run_bits;
 442             if (cost_get_here < cost_stay_here) {
 443                 path[swb+1][0].prev_idx = next_mincb;
 444                 path[swb+1][0].cost     = cost_get_here;
 445                 path[swb+1][0].run      = 1;
 446             } else {
 447                 path[swb+1][0].prev_idx = 0;
 448                 path[swb+1][0].cost     = cost_stay_here;
 449                 path[swb+1][0].run      = path[swb][0].run + 1;
 450             }
 451             next_minbits = path[swb+1][0].cost;
 452             next_mincb = 0;
 453             for (cb = 1; cb < 12; cb++) {
 454                 path[swb+1][cb].cost = 61450;
 455                 path[swb+1][cb].prev_idx = -1;
 456                 path[swb+1][cb].run = 0;
 457             }
 458         } else {
 459             float minbits = next_minbits;
 460             int mincb = next_mincb;
 461             int startcb = sce->band_type[win*16+swb];
 462             next_minbits = INFINITY;
 463             next_mincb = 0;
 464             for (cb = 0; cb < startcb; cb++) {
 465                 path[swb+1][cb].cost = 61450;
 466                 path[swb+1][cb].prev_idx = -1;
 467                 path[swb+1][cb].run = 0;
 468             }
 469             for (cb = startcb; cb < 12; cb++) {
 470                 float cost_stay_here, cost_get_here;
 471                 float bits = 0.0f;
 472                 for (w = 0; w < group_len; w++) {
 473                     bits += quantize_band_cost(s, sce->coeffs + start + w*128,
 474                                                s->scoefs + start + w*128, size,
 475                                                sce->sf_idx[(win+w)*16+swb], cb,
 476                                                0, INFINITY, NULL);
 477                 }
 478                 cost_stay_here = path[swb][cb].cost + bits;
 479                 cost_get_here  = minbits            + bits + run_bits + 4;
 480                 if (   run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run]
 481                     != run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1])
 482                     cost_stay_here += run_bits;
 483                 if (cost_get_here < cost_stay_here) {
 484                     path[swb+1][cb].prev_idx = mincb;
 485                     path[swb+1][cb].cost     = cost_get_here;
 486                     path[swb+1][cb].run      = 1;
 487                 } else {
 488                     path[swb+1][cb].prev_idx = cb;
 489                     path[swb+1][cb].cost     = cost_stay_here;
 490                     path[swb+1][cb].run      = path[swb][cb].run + 1;
 491                 }
 492                 if (path[swb+1][cb].cost < next_minbits) {
 493                     next_minbits = path[swb+1][cb].cost;
 494                     next_mincb = cb;
 495                 }
 496             }
 497         }
 498         start += sce->ics.swb_sizes[swb];
 499     }
 500
 501     //convert resulting path from backward-linked list
 502     stack_len = 0;
 503     idx       = 0;
 504     for (cb = 1; cb < 12; cb++)
 505         if (path[max_sfb][cb].cost < path[max_sfb][idx].cost)
 506             idx = cb;
 507     ppos = max_sfb;
 508     while (ppos > 0) {
 509         av_assert1(idx >= 0);
 510         cb = idx;
 511         stackrun[stack_len] = path[ppos][cb].run;
 512         stackcb [stack_len] = cb;
 513         idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx;
 514         ppos -= path[ppos][cb].run;
 515         stack_len++;
 516     }
 517     //perform actual band info encoding
 518     start = 0;
 519     for (i = stack_len - 1; i >= 0; i--) {
 520         put_bits(&s->pb, 4, stackcb[i]);
 521         count = stackrun[i];
 522         memset(sce->zeroes + win*16 + start, !stackcb[i], count);
 523         //XXX: memset when band_type is also uint8_t
 524         for (j = 0; j < count; j++) {
 525             sce->band_type[win*16 + start] =  stackcb[i];
 526             start++;
 527         }
 528         while (count >= run_esc) {
 529             put_bits(&s->pb, run_bits, run_esc);
 530             count -= run_esc;
 531         }
 532         put_bits(&s->pb, run_bits, count);
 533     }
 534 }
 535
 536 /** Return the minimum scalefactor where the quantized coef does not clip. */
 537 static av_always_inline uint8_t coef2minsf(float coef) {
 538     return av_clip_uint8(log2f(coef)*4 - 69 + SCALE_ONE_POS - SCALE_DIV_512);
 539 }
 540
 541 /** Return the maximum scalefactor where the quantized coef is not zero. */
 542 static av_always_inline uint8_t coef2maxsf(float coef) {
 543     return av_clip_uint8(log2f(coef)*4 +  6 + SCALE_ONE_POS - SCALE_DIV_512);
 544 }
 545
 546 typedef struct TrellisPath {
 547     float cost;
 548     int prev;
 549 } TrellisPath;
 550
 551 #define TRELLIS_STAGES 121
 552 #define TRELLIS_STATES (SCALE_MAX_DIFF+1)
 553
 554 static void search_for_quantizers_anmr(AVCodecContext *avctx, AACEncContext *s,
 555                                        SingleChannelElement *sce,
 556                                        const float lambda)
 557 {
 558     int q, w, w2, g, start = 0;
 559     int i, j;
 560     int idx;
 561     TrellisPath paths[TRELLIS_STAGES][TRELLIS_STATES];
 562     int bandaddr[TRELLIS_STAGES];
 563     int minq;
 564     float mincost;
 565     float q0f = FLT_MAX, q1f = 0.0f, qnrgf = 0.0f;
 566     int q0, q1, qcnt = 0;
 567
 568     for (i = 0; i < 1024; i++) {
 569         float t = fabsf(sce->coeffs[i]);
 570         if (t > 0.0f) {
 571             q0f = FFMIN(q0f, t);
 572             q1f = FFMAX(q1f, t);
 573             qnrgf += t*t;
 574             qcnt++;
 575         }
 576     }
 577
 578     if (!qcnt) {
 579         memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
 580         memset(sce->zeroes, 1, sizeof(sce->zeroes));
 581         return;
 582     }
 583
 584     //minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped
 585     q0 = coef2minsf(q0f);
 586     //maximum scalefactor index is when maximum coefficient after quantizing is still not zero
 587     q1 = coef2maxsf(q1f);
 588     if (q1 - q0 > 60) {
 589         int q0low  = q0;
 590         int q1high = q1;
 591         //minimum scalefactor index is when maximum nonzero coefficient after quantizing is not clipped
 592         int qnrg = av_clip_uint8(log2f(sqrtf(qnrgf/qcnt))*4 - 31 + SCALE_ONE_POS - SCALE_DIV_512);
 593         q1 = qnrg + 30;
 594         q0 = qnrg - 30;
 595         if (q0 < q0low) {
 596             q1 += q0low - q0;
 597             q0  = q0low;
 598         } else if (q1 > q1high) {
 599             q0 -= q1 - q1high;
 600             q1  = q1high;
 601         }
 602     }
 603
 604     for (i = 0; i < TRELLIS_STATES; i++) {
 605         paths[0][i].cost    = 0.0f;
 606         paths[0][i].prev    = -1;
 607     }
 608     for (j = 1; j < TRELLIS_STAGES; j++) {
 609         for (i = 0; i < TRELLIS_STATES; i++) {
 610             paths[j][i].cost    = INFINITY;
 611             paths[j][i].prev    = -2;
 612         }
 613     }
 614     idx = 1;
 615     abs_pow34_v(s->scoefs, sce->coeffs, 1024);
 616     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 617         start = w*128;
 618         for (g = 0; g < sce->ics.num_swb; g++) {
 619             const float *coefs = sce->coeffs + start;
 620             float qmin, qmax;
 621             int nz = 0;
 622
 623             bandaddr[idx] = w * 16 + g;
 624             qmin = INT_MAX;
 625             qmax = 0.0f;
 626             for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
 627                 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
 628                 if (band->energy <= band->threshold || band->threshold == 0.0f) {
 629                     sce->zeroes[(w+w2)*16+g] = 1;
 630                     continue;
 631                 }
 632                 sce->zeroes[(w+w2)*16+g] = 0;
 633                 nz = 1;
 634                 for (i = 0; i < sce->ics.swb_sizes[g]; i++) {
 635                     float t = fabsf(coefs[w2*128+i]);
 636                     if (t > 0.0f)
 637                         qmin = FFMIN(qmin, t);
 638                     qmax = FFMAX(qmax, t);
 639                 }
 640             }
 641             if (nz) {
 642                 int minscale, maxscale;
 643                 float minrd = INFINITY;
 644                 float maxval;
 645                 //minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped
 646                 minscale = coef2minsf(qmin);
 647                 //maximum scalefactor index is when maximum coefficient after quantizing is still not zero
 648                 maxscale = coef2maxsf(qmax);
 649                 minscale = av_clip(minscale - q0, 0, TRELLIS_STATES - 1);
 650                 maxscale = av_clip(maxscale - q0, 0, TRELLIS_STATES);
 651                 maxval = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], s->scoefs+start);
 652                 for (q = minscale; q < maxscale; q++) {
 653                     float dist = 0;
 654                     int cb = find_min_book(maxval, sce->sf_idx[w*16+g]);
 655                     for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
 656                         FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
 657                         dist += quantize_band_cost(s, coefs + w2*128, s->scoefs + start + w2*128, sce->ics.swb_sizes[g],
 658                                                    q + q0, cb, lambda / band->threshold, INFINITY, NULL);
 659                     }
 660                     minrd = FFMIN(minrd, dist);
 661
 662                     for (i = 0; i < q1 - q0; i++) {
 663                         float cost;
 664                         cost = paths[idx - 1][i].cost + dist
 665                                + ff_aac_scalefactor_bits[q - i + SCALE_DIFF_ZERO];
 666                         if (cost < paths[idx][q].cost) {
 667                             paths[idx][q].cost    = cost;
 668                             paths[idx][q].prev    = i;
 669                         }
 670                     }
 671                 }
 672             } else {
 673                 for (q = 0; q < q1 - q0; q++) {
 674                     paths[idx][q].cost = paths[idx - 1][q].cost + 1;
 675                     paths[idx][q].prev = q;
 676                 }
 677             }
 678             sce->zeroes[w*16+g] = !nz;
 679             start += sce->ics.swb_sizes[g];
 680             idx++;
 681         }
 682     }
 683     idx--;
 684     mincost = paths[idx][0].cost;
 685     minq    = 0;
 686     for (i = 1; i < TRELLIS_STATES; i++) {
 687         if (paths[idx][i].cost < mincost) {
 688             mincost = paths[idx][i].cost;
 689             minq = i;
 690         }
 691     }
 692     while (idx) {
 693         sce->sf_idx[bandaddr[idx]] = minq + q0;
 694         minq = paths[idx][minq].prev;
 695         idx--;
 696     }
 697     //set the same quantizers inside window groups
 698     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
 699         for (g = 0;  g < sce->ics.num_swb; g++)
 700             for (w2 = 1; w2 < sce->ics.group_len[w]; w2++)
 701                 sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g];
 702 }
 703
 704 /**
 705  * two-loop quantizers search taken from ISO 13818-7 Appendix C
 706  */
 707 static void search_for_quantizers_twoloop(AVCodecContext *avctx,
 708                                           AACEncContext *s,
 709                                           SingleChannelElement *sce,
 710                                           const float lambda)
 711 {
 712     int start = 0, i, w, w2, g;
 713     int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->channels;
 714     float dists[128] = { 0 }, uplims[128];
 715     float maxvals[128];
 716     int fflag, minscaler;
 717     int its  = 0;
 718     int allz = 0;
 719     float minthr = INFINITY;
 720
 721     // for values above this the decoder might end up in an endless loop
 722     // due to always having more bits than what can be encoded.
 723     destbits = FFMIN(destbits, 5800);
 724     //XXX: some heuristic to determine initial quantizers will reduce search time
 725     //determine zero bands and upper limits
 726     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 727         for (g = 0;  g < sce->ics.num_swb; g++) {
 728             int nz = 0;
 729             float uplim = 0.0f;
 730             for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
 731                 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
 732                 uplim += band->threshold;
 733                 if (band->energy <= band->threshold || band->threshold == 0.0f) {
 734                     sce->zeroes[(w+w2)*16+g] = 1;
 735                     continue;
 736                 }
 737                 nz = 1;
 738             }
 739             uplims[w*16+g] = uplim *512;
 740             sce->zeroes[w*16+g] = !nz;
 741             if (nz)
 742                 minthr = FFMIN(minthr, uplim);
 743             allz |= nz;
 744         }
 745     }
 746     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 747         for (g = 0;  g < sce->ics.num_swb; g++) {
 748             if (sce->zeroes[w*16+g]) {
 749                 sce->sf_idx[w*16+g] = SCALE_ONE_POS;
 750                 continue;
 751             }
 752             sce->sf_idx[w*16+g] = SCALE_ONE_POS + FFMIN(log2f(uplims[w*16+g]/minthr)*4,59);
 753         }
 754     }
 755
 756     if (!allz)
 757         return;
 758     abs_pow34_v(s->scoefs, sce->coeffs, 1024);
 759
 760     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 761         start = w*128;
 762         for (g = 0;  g < sce->ics.num_swb; g++) {
 763             const float *scaled = s->scoefs + start;
 764             maxvals[w*16+g] = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], scaled);
 765             start += sce->ics.swb_sizes[g];
 766         }
 767     }
 768
 769     //perform two-loop search
 770     //outer loop - improve quality
 771     do {
 772         int tbits, qstep;
 773         minscaler = sce->sf_idx[0];
 774         //inner loop - quantize spectrum to fit into given number of bits
 775         qstep = its ? 1 : 32;
 776         do {
 777             int prev = -1;
 778             tbits = 0;
 779             fflag = 0;
 780             for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 781                 start = w*128;
 782                 for (g = 0;  g < sce->ics.num_swb; g++) {
 783                     const float *coefs = sce->coeffs + start;
 784                     const float *scaled = s->scoefs + start;
 785                     int bits = 0;
 786                     int cb;
 787                     float dist = 0.0f;
 788
 789                     if (sce->zeroes[w*16+g] || sce->sf_idx[w*16+g] >= 218) {
 790                         start += sce->ics.swb_sizes[g];
 791                         continue;
 792                     }
 793                     minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]);
 794                     cb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]);
 795                     for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
 796                         int b;
 797                         dist += quantize_band_cost(s, coefs + w2*128,
 798                                                    scaled + w2*128,
 799                                                    sce->ics.swb_sizes[g],
 800                                                    sce->sf_idx[w*16+g],
 801                                                    cb,
 802                                                    1.0f,
 803                                                    INFINITY,
 804                                                    &b);
 805                         bits += b;
 806                     }
 807                     dists[w*16+g] = dist - bits;
 808                     if (prev != -1) {
 809                         bits += ff_aac_scalefactor_bits[sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO];
 810                     }
 811                     tbits += bits;
 812                     start += sce->ics.swb_sizes[g];
 813                     prev = sce->sf_idx[w*16+g];
 814                 }
 815             }
 816             if (tbits > destbits) {
 817                 for (i = 0; i < 128; i++)
 818                     if (sce->sf_idx[i] < 218 - qstep)
 819                         sce->sf_idx[i] += qstep;
 820             } else {
 821                 for (i = 0; i < 128; i++)
 822                     if (sce->sf_idx[i] > 60 - qstep)
 823                         sce->sf_idx[i] -= qstep;
 824             }
 825             qstep >>= 1;
 826             if (!qstep && tbits > destbits*1.02 && sce->sf_idx[0] < 217)
 827                 qstep = 1;
 828         } while (qstep);
 829
 830         fflag = 0;
 831         minscaler = av_clip(minscaler, 60, 255 - SCALE_MAX_DIFF);
 832         for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 833             for (g = 0; g < sce->ics.num_swb; g++) {
 834                 int prevsc = sce->sf_idx[w*16+g];
 835                 if (dists[w*16+g] > uplims[w*16+g] && sce->sf_idx[w*16+g] > 60) {
 836                     if (find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]-1))
 837                         sce->sf_idx[w*16+g]--;
 838                     else //Try to make sure there is some energy in every band
 839                         sce->sf_idx[w*16+g]-=2;
 840                 }
 841                 sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], minscaler, minscaler + SCALE_MAX_DIFF);
 842                 sce->sf_idx[w*16+g] = FFMIN(sce->sf_idx[w*16+g], 219);
 843                 if (sce->sf_idx[w*16+g] != prevsc)
 844                     fflag = 1;
 845                 sce->band_type[w*16+g] = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]);
 846             }
 847         }
 848         its++;
 849     } while (fflag && its < 10);
 850 }
 851
 852 static void search_for_quantizers_faac(AVCodecContext *avctx, AACEncContext *s,
 853                                        SingleChannelElement *sce,
 854                                        const float lambda)
 855 {
 856     int start = 0, i, w, w2, g;
 857     float uplim[128], maxq[128];
 858     int minq, maxsf;
 859     float distfact = ((sce->ics.num_windows > 1) ? 85.80 : 147.84) / lambda;
 860     int last = 0, lastband = 0, curband = 0;
 861     float avg_energy = 0.0;
 862     if (sce->ics.num_windows == 1) {
 863         start = 0;
 864         for (i = 0; i < 1024; i++) {
 865             if (i - start >= sce->ics.swb_sizes[curband]) {
 866                 start += sce->ics.swb_sizes[curband];
 867                 curband++;
 868             }
 869             if (sce->coeffs[i]) {
 870                 avg_energy += sce->coeffs[i] * sce->coeffs[i];
 871                 last = i;
 872                 lastband = curband;
 873             }
 874         }
 875     } else {
 876         for (w = 0; w < 8; w++) {
 877             const float *coeffs = sce->coeffs + w*128;
 878             curband = start = 0;
 879             for (i = 0; i < 128; i++) {
 880                 if (i - start >= sce->ics.swb_sizes[curband]) {
 881                     start += sce->ics.swb_sizes[curband];
 882                     curband++;
 883                 }
 884                 if (coeffs[i]) {
 885                     avg_energy += coeffs[i] * coeffs[i];
 886                     last = FFMAX(last, i);
 887                     lastband = FFMAX(lastband, curband);
 888                 }
 889             }
 890         }
 891     }
 892     last++;
 893     avg_energy /= last;
 894     if (avg_energy == 0.0f) {
 895         for (i = 0; i < FF_ARRAY_ELEMS(sce->sf_idx); i++)
 896             sce->sf_idx[i] = SCALE_ONE_POS;
 897         return;
 898     }
 899     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 900         start = w*128;
 901         for (g = 0; g < sce->ics.num_swb; g++) {
 902             float *coefs   = sce->coeffs + start;
 903             const int size = sce->ics.swb_sizes[g];
 904             int start2 = start, end2 = start + size, peakpos = start;
 905             float maxval = -1, thr = 0.0f, t;
 906             maxq[w*16+g] = 0.0f;
 907             if (g > lastband) {
 908                 maxq[w*16+g] = 0.0f;
 909                 start += size;
 910                 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++)
 911                     memset(coefs + w2*128, 0, sizeof(coefs[0])*size);
 912                 continue;
 913             }
 914             for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
 915                 for (i = 0; i < size; i++) {
 916                     float t = coefs[w2*128+i]*coefs[w2*128+i];
 917                     maxq[w*16+g] = FFMAX(maxq[w*16+g], fabsf(coefs[w2*128 + i]));
 918                     thr += t;
 919                     if (sce->ics.num_windows == 1 && maxval < t) {
 920                         maxval  = t;
 921                         peakpos = start+i;
 922                     }
 923                 }
 924             }
 925             if (sce->ics.num_windows == 1) {
 926                 start2 = FFMAX(peakpos - 2, start2);
 927                 end2   = FFMIN(peakpos + 3, end2);
 928             } else {
 929                 start2 -= start;
 930                 end2   -= start;
 931             }
 932             start += size;
 933             thr = pow(thr / (avg_energy * (end2 - start2)), 0.3 + 0.1*(lastband - g) / lastband);
 934             t   = 1.0 - (1.0 * start2 / last);
 935             uplim[w*16+g] = distfact / (1.4 * thr + t*t*t + 0.075);
 936         }
 937     }
 938     memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
 939     abs_pow34_v(s->scoefs, sce->coeffs, 1024);
 940     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
 941         start = w*128;
 942         for (g = 0;  g < sce->ics.num_swb; g++) {
 943             const float *coefs  = sce->coeffs + start;
 944             const float *scaled = s->scoefs   + start;
 945             const int size      = sce->ics.swb_sizes[g];
 946             int scf, prev_scf, step;
 947             int min_scf = -1, max_scf = 256;
 948             float curdiff;
 949             if (maxq[w*16+g] < 21.544) {
 950                 sce->zeroes[w*16+g] = 1;
 951                 start += size;
 952                 continue;
 953             }
 954             sce->zeroes[w*16+g] = 0;
 955             scf  = prev_scf = av_clip(SCALE_ONE_POS - SCALE_DIV_512 - log2f(1/maxq[w*16+g])*16/3, 60, 218);
 956             step = 16;
 957             for (;;) {
 958                 float dist = 0.0f;
 959                 int quant_max;
 960
 961                 for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
 962                     int b;
 963                     dist += quantize_band_cost(s, coefs + w2*128,
 964                                                scaled + w2*128,
 965                                                sce->ics.swb_sizes[g],
 966                                                scf,
 967                                                ESC_BT,
 968                                                lambda,
 969                                                INFINITY,
 970                                                &b);
 971                     dist -= b;
 972                 }
 973                 dist *= 1.0f / 512.0f / lambda;
 974                 quant_max = quant(maxq[w*16+g], ff_aac_pow2sf_tab[POW_SF2_ZERO - scf + SCALE_ONE_POS - SCALE_DIV_512]);
 975                 if (quant_max >= 8191) { // too much, return to the previous quantizer
 976                     sce->sf_idx[w*16+g] = prev_scf;
 977                     break;
 978                 }
 979                 prev_scf = scf;
 980                 curdiff = fabsf(dist - uplim[w*16+g]);
 981                 if (curdiff <= 1.0f)
 982                     step = 0;
 983                 else
 984                     step = log2f(curdiff);
 985                 if (dist > uplim[w*16+g])
 986                     step = -step;
 987                 scf += step;
 988                 scf = av_clip_uint8(scf);
 989                 step = scf - prev_scf;
 990                 if (FFABS(step) <= 1 || (step > 0 && scf >= max_scf) || (step < 0 && scf <= min_scf)) {
 991                     sce->sf_idx[w*16+g] = av_clip(scf, min_scf, max_scf);
 992                     break;
 993                 }
 994                 if (step > 0)
 995                     min_scf = prev_scf;
 996                 else
 997                     max_scf = prev_scf;
 998             }
 999             start += size;
1000         }
1001     }
1002     minq = sce->sf_idx[0] ? sce->sf_idx[0] : INT_MAX;
1003     for (i = 1; i < 128; i++) {
1004         if (!sce->sf_idx[i])
1005             sce->sf_idx[i] = sce->sf_idx[i-1];
1006         else
1007             minq = FFMIN(minq, sce->sf_idx[i]);
1008     }
1009     if (minq == INT_MAX)
1010         minq = 0;
1011     minq = FFMIN(minq, SCALE_MAX_POS);
1012     maxsf = FFMIN(minq + SCALE_MAX_DIFF, SCALE_MAX_POS);
1013     for (i = 126; i >= 0; i--) {
1014         if (!sce->sf_idx[i])
1015             sce->sf_idx[i] = sce->sf_idx[i+1];
1016         sce->sf_idx[i] = av_clip(sce->sf_idx[i], minq, maxsf);
1017     }
1018 }
1019
1020 static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s,
1021                                        SingleChannelElement *sce,
1022                                        const float lambda)
1023 {
1024     int i, w, w2, g;
1025     int minq = 255;
1026
1027     memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
1028     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
1029         for (g = 0; g < sce->ics.num_swb; g++) {
1030             for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
1031                 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
1032                 if (band->energy <= band->threshold) {
1033                     sce->sf_idx[(w+w2)*16+g] = 218;
1034                     sce->zeroes[(w+w2)*16+g] = 1;
1035                 } else {
1036                     sce->sf_idx[(w+w2)*16+g] = av_clip(SCALE_ONE_POS - SCALE_DIV_512 + log2f(band->threshold), 80, 218);
1037                     sce->zeroes[(w+w2)*16+g] = 0;
1038                 }
1039                 minq = FFMIN(minq, sce->sf_idx[(w+w2)*16+g]);
1040             }
1041         }
1042     }
1043     for (i = 0; i < 128; i++) {
1044         sce->sf_idx[i] = 140;
1045         //av_clip(sce->sf_idx[i], minq, minq + SCALE_MAX_DIFF - 1);
1046     }
1047     //set the same quantizers inside window groups
1048     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
1049         for (g = 0;  g < sce->ics.num_swb; g++)
1050             for (w2 = 1; w2 < sce->ics.group_len[w]; w2++)
1051                 sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g];
1052 }
1053
1054 static void search_for_ms(AACEncContext *s, ChannelElement *cpe,
1055                           const float lambda)
1056 {
1057     int start = 0, i, w, w2, g;
1058     float M[128], S[128];
1059     float *L34 = s->scoefs, *R34 = s->scoefs + 128, *M34 = s->scoefs + 128*2, *S34 = s->scoefs + 128*3;
1060     SingleChannelElement *sce0 = &cpe->ch[0];
1061     SingleChannelElement *sce1 = &cpe->ch[1];
1062     if (!cpe->common_window)
1063         return;
1064     for (w = 0; w < sce0->ics.num_windows; w += sce0->ics.group_len[w]) {
1065         for (g = 0;  g < sce0->ics.num_swb; g++) {
1066             if (!cpe->ch[0].zeroes[w*16+g] && !cpe->ch[1].zeroes[w*16+g]) {
1067                 float dist1 = 0.0f, dist2 = 0.0f;
1068                 for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) {
1069                     FFPsyBand *band0 = &s->psy.ch[s->cur_channel+0].psy_bands[(w+w2)*16+g];
1070                     FFPsyBand *band1 = &s->psy.ch[s->cur_channel+1].psy_bands[(w+w2)*16+g];
1071                     float minthr = FFMIN(band0->threshold, band1->threshold);
1072                     float maxthr = FFMAX(band0->threshold, band1->threshold);
1073                     for (i = 0; i < sce0->ics.swb_sizes[g]; i++) {
1074                         M[i] = (sce0->coeffs[start+w2*128+i]
1075                               + sce1->coeffs[start+w2*128+i]) * 0.5;
1076                         S[i] =  M[i]
1077                               - sce1->coeffs[start+w2*128+i];
1078                     }
1079                     abs_pow34_v(L34, sce0->coeffs+start+w2*128, sce0->ics.swb_sizes[g]);
1080                     abs_pow34_v(R34, sce1->coeffs+start+w2*128, sce0->ics.swb_sizes[g]);
1081                     abs_pow34_v(M34, M,                         sce0->ics.swb_sizes[g]);
1082                     abs_pow34_v(S34, S,                         sce0->ics.swb_sizes[g]);
1083                     dist1 += quantize_band_cost(s, sce0->coeffs + start + w2*128,
1084                                                 L34,
1085                                                 sce0->ics.swb_sizes[g],
1086                                                 sce0->sf_idx[(w+w2)*16+g],
1087                                                 sce0->band_type[(w+w2)*16+g],
1088                                                 lambda / band0->threshold, INFINITY, NULL);
1089                     dist1 += quantize_band_cost(s, sce1->coeffs + start + w2*128,
1090                                                 R34,
1091                                                 sce1->ics.swb_sizes[g],
1092                                                 sce1->sf_idx[(w+w2)*16+g],
1093                                                 sce1->band_type[(w+w2)*16+g],
1094                                                 lambda / band1->threshold, INFINITY, NULL);
1095                     dist2 += quantize_band_cost(s, M,
1096                                                 M34,
1097                                                 sce0->ics.swb_sizes[g],
1098                                                 sce0->sf_idx[(w+w2)*16+g],
1099                                                 sce0->band_type[(w+w2)*16+g],
1100                                                 lambda / maxthr, INFINITY, NULL);
1101                     dist2 += quantize_band_cost(s, S,
1102                                                 S34,
1103                                                 sce1->ics.swb_sizes[g],
1104                                                 sce1->sf_idx[(w+w2)*16+g],
1105                                                 sce1->band_type[(w+w2)*16+g],
1106                                                 lambda / minthr, INFINITY, NULL);
1107                 }
1108                 cpe->ms_mask[w*16+g] = dist2 < dist1;
1109             }
1110             start += sce0->ics.swb_sizes[g];
1111         }
1112     }
1113 }
1114
1115 AACCoefficientsEncoder ff_aac_coders[AAC_CODER_NB] = {
1116     {
1117         search_for_quantizers_faac,
1118         encode_window_bands_info,
1119         quantize_and_encode_band,
1120         search_for_ms,
1121     },
1122     {
1123         search_for_quantizers_anmr,
1124         encode_window_bands_info,
1125         quantize_and_encode_band,
1126         search_for_ms,
1127     },
1128     {
1129         search_for_quantizers_twoloop,
1130         codebook_trellis_rate,
1131         quantize_and_encode_band,
1132         search_for_ms,
1133     },
1134     {
1135         search_for_quantizers_fast,
1136         encode_window_bands_info,
1137         quantize_and_encode_band,
1138         search_for_ms,
1139     },
1140 };