git.sesse.net Git - vlc/blob - plugins/mpeg_adec/adec_layer2.c

   1 /*****************************************************************************
   2  * adec_layer2.c: MPEG Layer II audio decoder
   3  *****************************************************************************
   4  * Copyright (C) 1999, 2000 VideoLAN
   5  * $Id: adec_layer2.c,v 1.1 2001/11/13 12:09:18 henri Exp $
   6  *
   7  * Authors: Michel Kaempf <maxx@via.ecp.fr>
   8  *          Michel Lespinasse <walken@via.ecp.fr>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  23  *****************************************************************************/
  24
  25 /*
  26  * TODO :
  27  *
  28  * - optimiser les NeedBits() et les GetBits() du code là où c'est possible ;
  29  *
  30  */
  31
  32 #include "defs.h"
  33
  34 #include <stdlib.h>                                                  /* NULL */
  35 #include <string.h>                                    /* memcpy(), memset() */
  36
  37 #include "config.h"
  38 #include "common.h"
  39 #include "threads.h"
  40 #include "mtime.h"
  41 #include "modules_export.h"
  42 #include "stream_control.h"
  43 #include "input_ext-dec.h"
  44
  45 #include "mpeg_adec_generic.h"
  46 #include "mpeg_adec.h"
  47 #include "adec_math.h"                                     /* DCT32(), PCM() */
  48
  49 /**** wkn ****/
  50
  51 static float adec_scalefactor_table[64] =
  52 {   /* 2 ^ (1 - i/3) */
  53     2.0000000000000000, 1.5874010519681994, 1.2599210498948732,
  54     1.0000000000000000, 0.7937005259840998, 0.6299605249474366,
  55     0.5000000000000000, 0.3968502629920499, 0.3149802624737183,
  56     0.2500000000000000, 0.1984251314960249, 0.1574901312368591,
  57     0.1250000000000000, 0.0992125657480125, 0.0787450656184296,
  58     0.0625000000000000, 0.0496062828740062, 0.0393725328092148,
  59     0.0312500000000000, 0.0248031414370031, 0.0196862664046074,
  60     0.0156250000000000, 0.0124015707185016, 0.0098431332023037,
  61     0.0078125000000000, 0.0062007853592508, 0.0049215666011518,
  62     0.0039062500000000, 0.0031003926796254, 0.0024607833005759,
  63     0.0019531250000000, 0.0015501963398127, 0.0012303916502880,
  64     0.0009765625000000, 0.0007750981699063, 0.0006151958251440,
  65     0.0004882812500000, 0.0003875490849532, 0.0003075979125720,
  66     0.0002441406250000, 0.0001937745424766, 0.0001537989562860,
  67     0.0001220703125000, 0.0000968872712383, 0.0000768994781430,
  68     0.0000610351562500, 0.0000484436356191, 0.0000384497390715,
  69     0.0000305175781250, 0.0000242218178096, 0.0000192248695357,
  70     0.0000152587890625, 0.0000121109089048, 0.0000096124347679,
  71     0.0000076293945312, 0.0000060554544524, 0.0000048062173839,
  72     0.0000038146972656, 0.0000030277272262, 0.0000024031086920,
  73     0.0000019073486328, 0.0000015138636131, 0.0000012015543460,
  74     0.0000009536743164 /* last element is not in the standard... invalid ??? */
  75 };
  76
  77 static float adec_slope_table[15] =
  78 {
  79     0.6666666666666666, 0.2857142857142857, 0.1333333333333333,
  80     0.0645161290322581, 0.0317460317460317, 0.0157480314960630,
  81     0.0078431372549020, 0.0039138943248532, 0.0019550342130987,
  82     0.0009770395701026, 0.0004884004884005, 0.0002441704309608,
  83     0.0001220777635354, 0.0000610370189520, 0.0000305180437934
  84 };
  85
  86 static float adec_offset_table[15] =
  87 {
  88     -0.6666666666666666, -0.8571428571428571, -0.9333333333333333,
  89     -0.9677419354838710, -0.9841269841269841, -0.9921259842519685,
  90     -0.9960784313725490, -0.9980430528375733, -0.9990224828934506,
  91     -0.9995114802149487, -0.9997557997557998, -0.9998779147845196,
  92     -0.9999389611182323, -0.9999694814905240, -0.9999847409781033
  93 };
  94
  95 static int adec_bound_table[4] = { 4, 8, 12, 16 };
  96
  97 typedef struct
  98 {
  99     s8 nbal[32];
 100     u8 * alloc[32];
 101 } alloc_table_t;
 102
 103 #define L3 -1
 104 #define L5 -2
 105 #define L9 -3
 106
 107 static void adec_layer2_get_table( u32 header, u8 freq_table[15],
 108                                    alloc_table_t ** alloc, int * sblimit )
 109 {
 110     static s8 table_ab0[16] =
 111     {
 112         0, L3, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
 113     };
 114     static s8 table_ab3[16] =
 115     {
 116         0, L3, L5, 3, L9, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 16
 117     };
 118     static s8 table_ab11[8] =
 119     {
 120         0, L3, L5, 3, L9, 4, 5, 16
 121     };
 122     static s8 table_ab23[8] =
 123     {
 124         0, L3, L5, 16
 125     };
 126     static alloc_table_t mpeg1_ab =
 127     {
 128         {4,4,4,4,4,4,4,4,4,4,4,3,3,3,3,3,3,3,3,3,3,3,3,2,2,2,2,2,2,2,0,0},
 129         {table_ab0,  table_ab0,  table_ab0,  table_ab3,
 130          table_ab3,  table_ab3,  table_ab3,  table_ab3,
 131          table_ab3,  table_ab3,  table_ab3,  table_ab11,
 132          table_ab11, table_ab11, table_ab11, table_ab11,
 133          table_ab11, table_ab11, table_ab11, table_ab11,
 134          table_ab11, table_ab11, table_ab11, table_ab23,
 135          table_ab23, table_ab23, table_ab23, table_ab23,
 136          table_ab23, table_ab23, NULL, NULL}
 137     };
 138
 139     static s8 table_cd[16] =
 140     {
 141         0, L3, L5, L9, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
 142     };
 143     static alloc_table_t mpeg1_cd =
 144     {
 145         {4,4,3,3,3,3,3,3,3,3,3,3,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
 146         {table_cd, table_cd, table_cd, table_cd,
 147          table_cd, table_cd, table_cd, table_cd,
 148          table_cd, table_cd, table_cd, table_cd,
 149          NULL, NULL, NULL, NULL,
 150          NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 151          NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL}
 152     };
 153
 154     static s8 table_0[16] =
 155     {
 156         0, L3, L5, 3, L9, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
 157     };
 158     static s8 table_4[8] =
 159     {
 160         0, L3, L5, L9, 4, 5, 6, 7
 161     };
 162     static alloc_table_t mpeg2 =
 163     {
 164         {4,4,4,4,3,3,3,3,3,3,3,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,0,0},
 165         {table_0, table_0, table_0, table_0,
 166          table_4, table_4, table_4, table_4,
 167          table_4, table_4, table_4, table_4,
 168          table_4, table_4, table_4, table_4,
 169          table_4, table_4, table_4, table_4,
 170          table_4, table_4, table_4, table_4,
 171          table_4, table_4, table_4, table_4,
 172          table_4, table_4, NULL, NULL}
 173     };
 174
 175     static alloc_table_t * alloc_table [4] =
 176     {
 177         &mpeg2, &mpeg1_cd, &mpeg1_ab, &mpeg1_ab
 178     };
 179     static int sblimit_table[12] =
 180     {
 181         30, 8, 27, 30, 30, 8, 27, 27, 30, 12, 27, 30
 182     };
 183
 184     int index;
 185
 186     if (!(header & 0x80000))
 187     {
 188         index = 0; /* mpeg2 */
 189     }
 190     else
 191     {
 192         index = (header >> 12) & 15; /* mpeg1, bitrate */
 193         index = freq_table [index];
 194     }
 195
 196     *alloc = alloc_table[index];
 197     index |= (header >> 8) & 12;
 198     *sblimit = sblimit_table[index];
 199 }
 200
 201 int adec_layer2_mono( adec_thread_t * p_adec, s16 * buffer )
 202 {
 203     static u8 freq_table[15] = {2, 1, 1, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2};
 204     static float L3_table[3] = {-2/3.0, 0, 2/3.0};
 205     static float L5_table[5] = {-4/5.0, -2/5.0, 0, 2/5.0, 4/5.0};
 206     static float L9_table[9] = {-8/9.0, -6/9.0, -4/9.0, -2/9.0, 0,
 207                                 2/9.0, 4/9.0, 6/9.0, 8/9.0};
 208
 209     s8 allocation[32];
 210     u8 scfsi[32];
 211     float slope[3][32];
 212     float offset[3][32];
 213     float sample[3][32];
 214     alloc_table_t * alloc_table;
 215
 216     int sblimit;
 217     int sb;
 218     int gr0, gr1;
 219     int s;
 220     int i_read_bits = 0;
 221
 222     /* get the right allocation table */
 223     adec_layer2_get_table (p_adec->header, freq_table, &alloc_table, &sblimit);
 224
 225     /* parse allocation */
 226     //sblimit=27;
 227
 228     for (sb = 0; sb < sblimit; sb++)
 229     {
 230         int index;
 231
 232         index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
 233         i_read_bits += alloc_table->nbal[sb];
 234
 235         allocation[sb] = alloc_table->alloc[sb][index];
 236     }
 237
 238     /* parse scfsi */
 239
 240     for (sb = 0; sb < sblimit; sb++)
 241     {
 242         if (allocation[sb])
 243         {
 244             scfsi[sb] = GetBits (&p_adec->bit_stream, 2);
 245             i_read_bits += 2;
 246         }
 247     }
 248
 249     /* parse scalefactors */
 250
 251     for (sb = 0; sb < sblimit; sb++)
 252     {
 253         if (allocation[sb])
 254         {
 255             int index_0, index_1, index_2;
 256
 257             switch (scfsi[sb])
 258             {
 259             case 0:
 260                 index_0 = GetBits(&p_adec->bit_stream,6);
 261                 index_1 = GetBits(&p_adec->bit_stream,6);
 262                 index_2 = GetBits(&p_adec->bit_stream,6);
 263                 i_read_bits += 18;
 264
 265                 if (allocation[sb] < 0)
 266                 {
 267                     slope[0][sb] = adec_scalefactor_table[index_0];
 268                     slope[1][sb] = adec_scalefactor_table[index_1];
 269                     slope[2][sb] = adec_scalefactor_table[index_2];
 270                 }
 271                 else
 272                 {
 273                     float r_scalefactor;
 274                     float r_slope, r_offset;
 275
 276                     r_slope = adec_slope_table[allocation[sb]-2];
 277                     r_offset = adec_offset_table[allocation[sb]-2];
 278
 279                     r_scalefactor = adec_scalefactor_table[index_0];
 280                     slope[0][sb] = r_slope * r_scalefactor;
 281                     offset[0][sb] = r_offset * r_scalefactor;
 282
 283                     r_scalefactor = adec_scalefactor_table[index_1];
 284                     slope[1][sb] = r_slope * r_scalefactor;
 285                     offset[1][sb] = r_offset * r_scalefactor;
 286
 287                     r_scalefactor = adec_scalefactor_table[index_2];
 288                     slope[2][sb] = r_slope * r_scalefactor;
 289                     offset[2][sb] = r_offset * r_scalefactor;
 290                 }
 291                 break;
 292
 293             case 1:
 294                 index_0 = GetBits(&p_adec->bit_stream,6);
 295                 index_1 = GetBits(&p_adec->bit_stream,6);
 296                 i_read_bits += 12;
 297
 298                 if (allocation[sb] < 0)
 299                 {
 300                     slope[0][sb] = slope[1][sb] =
 301                         adec_scalefactor_table[index_0];
 302                     slope[2][sb] = adec_scalefactor_table[index_1];
 303                 }
 304                 else
 305                 {
 306                     float r_scalefactor;
 307                     float r_slope, r_offset;
 308
 309                     r_slope = adec_slope_table[allocation[sb]-2];
 310                     r_offset = adec_offset_table[allocation[sb]-2];
 311
 312                     r_scalefactor = adec_scalefactor_table[index_0];
 313                     slope[0][sb] = slope[1][sb] = r_slope * r_scalefactor;
 314                     offset[0][sb] = offset[1][sb] =
 315                         r_offset * r_scalefactor;
 316
 317                     r_scalefactor = adec_scalefactor_table[index_1];
 318                     slope[2][sb] = r_slope * r_scalefactor;
 319                     offset[2][sb] = r_offset * r_scalefactor;
 320                 }
 321                 break;
 322
 323             case 2:
 324                 index_0 = GetBits( &p_adec->bit_stream, 6 );
 325                 i_read_bits += 6;
 326
 327                 if (allocation[sb] < 0)
 328                 {
 329                     slope[0][sb] = slope[1][sb] = slope[2][sb] =
 330                         adec_scalefactor_table[index_0];
 331                 }
 332                 else
 333                 {
 334                     float r_scalefactor;
 335                     float r_slope, r_offset;
 336
 337                     r_slope = adec_slope_table[allocation[sb]-2];
 338                     r_offset = adec_offset_table[allocation[sb]-2];
 339
 340                     r_scalefactor = adec_scalefactor_table[index_0];
 341                     slope[0][sb] = slope[1][sb] = slope[2][sb] =
 342                         r_slope * r_scalefactor;
 343                     offset[0][sb] = offset[1][sb] = offset[2][sb] =
 344                         r_offset * r_scalefactor;
 345                 }
 346                 break;
 347
 348             case 3:
 349                 index_0 = GetBits(&p_adec->bit_stream,6);
 350                 index_1 = GetBits(&p_adec->bit_stream,6);
 351                 i_read_bits += 12;
 352
 353                 if (allocation[sb] < 0)
 354                 {
 355                     slope[0][sb] = adec_scalefactor_table[index_0];
 356                     slope[1][sb] = slope[2][sb] =
 357                         adec_scalefactor_table[index_1];
 358                 }
 359                 else
 360                 {
 361                     float r_scalefactor;
 362                     float r_slope, r_offset;
 363
 364                     r_slope = adec_slope_table[allocation[sb]-2];
 365                     r_offset = adec_offset_table[allocation[sb]-2];
 366
 367                     r_scalefactor = adec_scalefactor_table[index_0];
 368                     slope[0][sb] = r_slope * r_scalefactor;
 369                     offset[0][sb] = r_offset * r_scalefactor;
 370
 371                     r_scalefactor = adec_scalefactor_table[index_1];
 372                     slope[1][sb] = slope[2][sb] = r_slope * r_scalefactor;
 373                     offset[1][sb] = offset[2][sb] =
 374                         r_offset * r_scalefactor;
 375                 }
 376                 break;
 377             }
 378         }
 379     }
 380
 381     /* parse samples */
 382
 383     for (gr0 = 0; gr0 < 3; gr0++)
 384     {
 385         for (gr1 = 0; gr1 < 4; gr1++)
 386         {
 387             s16 * XXX_buf;
 388
 389             for (sb = 0; sb < sblimit; sb++)
 390             {
 391                 int code;
 392
 393                 switch (allocation[sb])
 394                 {
 395                     case 0:
 396                         sample[0][sb] = sample[1][sb] = sample[2][sb] = 0;
 397                         break;
 398
 399                     case L3:
 400                         code = GetBits( &p_adec->bit_stream, 5 );
 401                         i_read_bits += 5;
 402
 403                         sample[0][sb] = slope[gr0][sb] * L3_table[code % 3];
 404                         code /= 3;
 405                         sample[1][sb] = slope[gr0][sb] * L3_table[code % 3];
 406                         code /= 3;
 407                         sample[2][sb] = slope[gr0][sb] * L3_table[code];
 408                     break;
 409
 410                     case L5:
 411                         code = GetBits( &p_adec->bit_stream, 7 );
 412                         i_read_bits += 7;
 413
 414                         sample[0][sb] = slope[gr0][sb] * L5_table[code % 5];
 415                         code /= 5;
 416                         sample[1][sb] = slope[gr0][sb] * L5_table[code % 5];
 417                         code /= 5;
 418                         sample[2][sb] = slope[gr0][sb] * L5_table[code];
 419                     break;
 420
 421                     case L9:
 422                         code = GetBits( &p_adec->bit_stream, 10 );
 423                         i_read_bits += 10;
 424
 425                         sample[0][sb] = slope[gr0][sb] * L9_table[code % 9];
 426                         code /= 9;
 427                         sample[1][sb] = slope[gr0][sb] * L9_table[code % 9];
 428                         code /= 9;
 429                         sample[2][sb] = slope[gr0][sb] * L9_table[code];
 430                     break;
 431
 432                     default:
 433                         for (s = 0; s < 3; s++)
 434                         {
 435                             code = GetBits( &p_adec->bit_stream,
 436                                             allocation[sb] );
 437                             i_read_bits += allocation[sb];
 438
 439                             sample[s][sb] =
 440                                 slope[gr0][sb] * code + offset[gr0][sb];
 441                         }
 442                 }
 443             }
 444
 445             for (; sb < 32; sb++)
 446             {
 447                 sample[0][sb] = sample[1][sb] = sample[2][sb] = 0;
 448             }
 449
 450             for (s = 0; s < 3; s++)
 451             {
 452                 DCT32 (sample[s], &p_adec->bank_0);
 453                 XXX_buf = buffer;
 454                 PCM (&p_adec->bank_0, &XXX_buf, 2);
 455
 456                 /* FIXME: one shouldn't have to do it twice ! */
 457                 DCT32 (sample[s], &p_adec->bank_1);
 458                 XXX_buf = buffer+1;
 459                 PCM (&p_adec->bank_1, &XXX_buf, 2);
 460
 461                 buffer += 64;
 462             }
 463         }
 464     }
 465
 466     p_adec->i_read_bits += i_read_bits;
 467
 468     return 0;
 469 }
 470
 471 int adec_layer2_stereo( adec_thread_t * p_adec, s16 * buffer )
 472 {
 473     static u8 freq_table[15] = {3, 0, 0, 0, 1, 0, 1, 2, 2, 2, 3, 3, 3, 3, 3};
 474     static float L3_table[3] = {-2/3.0, 0, 2/3.0};
 475     static float L5_table[5] = {-4/5.0, -2/5.0, 0, 2/5.0, 4/5.0};
 476     static float L9_table[9] = {-8/9.0, -6/9.0, -4/9.0, -2/9.0, 0,
 477                                 2/9.0, 4/9.0, 6/9.0, 8/9.0};
 478
 479     s8 allocation_0[32], allocation_1[32];
 480     u8 scfsi_0[32], scfsi_1[32];
 481     float slope_0[3][32], slope_1[3][32];
 482     float offset_0[3][32], offset_1[3][32];
 483     float sample_0[3][32], sample_1[3][32];
 484     alloc_table_t * alloc_table;
 485
 486     int sblimit;
 487     int bound;
 488     int sb;
 489     int gr0, gr1;
 490     int s;
 491     int i_read_bits = 0;
 492
 493     /* get the right allocation table */
 494     adec_layer2_get_table (p_adec->header, freq_table, &alloc_table, &sblimit);
 495
 496     /* calculate bound */
 497     bound = sblimit;
 498     if ((p_adec->header & 0xc0) == 0x40) { /* intensity stereo */
 499         int index;
 500         index = (p_adec->header >> 4) & 3;
 501         if (adec_bound_table[index] < sblimit)
 502         {
 503             bound = adec_bound_table[index];
 504         }
 505     }
 506
 507     /* parse allocation */
 508
 509     for (sb = 0; sb < bound; sb++)
 510     {
 511         int index;
 512
 513         index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
 514         allocation_0[sb] = alloc_table->alloc[sb][index];
 515
 516         index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
 517         allocation_1[sb] = alloc_table->alloc[sb][index];
 518
 519         i_read_bits += alloc_table->nbal[sb] * 2;
 520     }
 521
 522     for (; sb < sblimit; sb++)
 523     {
 524         int index;
 525
 526         index = GetBits( &p_adec->bit_stream, alloc_table->nbal[sb] );
 527         allocation_0[sb] = allocation_1[sb] = alloc_table->alloc[sb][index];
 528         i_read_bits += alloc_table->nbal[sb];
 529     }
 530
 531     /* parse scfsi */
 532
 533     for (sb = 0; sb < sblimit; sb++)
 534     {
 535         if (allocation_0[sb])
 536         {
 537             scfsi_0[sb] = GetBits (&p_adec->bit_stream, 2);
 538             i_read_bits += 2;
 539         }
 540
 541         if (allocation_1[sb])
 542         {
 543             scfsi_1[sb] = GetBits (&p_adec->bit_stream, 2);
 544             i_read_bits += 2;
 545         }
 546     }
 547
 548     /* parse scalefactors */
 549
 550     for (sb = 0; sb < sblimit; sb++)
 551     {
 552         if (allocation_0[sb])
 553         {
 554             int index_0, index_1, index_2;
 555
 556             switch (scfsi_0[sb])
 557             {
 558             case 0:
 559                 index_0 = GetBits(&p_adec->bit_stream,6);
 560                 index_1 = GetBits(&p_adec->bit_stream,6);
 561                 index_2 = GetBits(&p_adec->bit_stream,6);
 562                 i_read_bits += 18;
 563
 564                 if (allocation_0[sb] < 0)
 565                 {
 566                     slope_0[0][sb] = adec_scalefactor_table[index_0];
 567                     slope_0[1][sb] = adec_scalefactor_table[index_1];
 568                     slope_0[2][sb] = adec_scalefactor_table[index_2];
 569                 }
 570                 else
 571                 {
 572                     float scalefactor;
 573                     float slope, offset;
 574
 575                     slope = adec_slope_table[allocation_0[sb]-2];
 576                     offset = adec_offset_table[allocation_0[sb]-2];
 577
 578                     scalefactor = adec_scalefactor_table[index_0];
 579                     slope_0[0][sb] = slope * scalefactor;
 580                     offset_0[0][sb] = offset * scalefactor;
 581
 582                     scalefactor = adec_scalefactor_table[index_1];
 583                     slope_0[1][sb] = slope * scalefactor;
 584                     offset_0[1][sb] = offset * scalefactor;
 585
 586                     scalefactor = adec_scalefactor_table[index_2];
 587                     slope_0[2][sb] = slope * scalefactor;
 588                     offset_0[2][sb] = offset * scalefactor;
 589                 }
 590                 break;
 591
 592             case 1:
 593                 index_0 = GetBits(&p_adec->bit_stream,6);
 594                 index_1 = GetBits(&p_adec->bit_stream,6);
 595                 i_read_bits += 12;
 596
 597                 if (allocation_0[sb] < 0)
 598                 {
 599                     slope_0[0][sb] = slope_0[1][sb] =
 600                         adec_scalefactor_table[index_0];
 601                     slope_0[2][sb] = adec_scalefactor_table[index_1];
 602                 }
 603                 else
 604                 {
 605                     float scalefactor;
 606                     float slope, offset;
 607
 608                     slope = adec_slope_table[allocation_0[sb]-2];
 609                     offset = adec_offset_table[allocation_0[sb]-2];
 610
 611                     scalefactor = adec_scalefactor_table[index_0];
 612                     slope_0[0][sb] = slope_0[1][sb] = slope * scalefactor;
 613                     offset_0[0][sb] = offset_0[1][sb] =
 614                             offset * scalefactor;
 615
 616                     scalefactor = adec_scalefactor_table[index_1];
 617                     slope_0[2][sb] = slope * scalefactor;
 618                     offset_0[2][sb] = offset * scalefactor;
 619                 }
 620                 break;
 621
 622             case 2:
 623                 index_0 = GetBits( &p_adec->bit_stream, 6 );
 624                 i_read_bits += 6;
 625
 626                 if (allocation_0[sb] < 0)
 627                 {
 628                     slope_0[0][sb] = slope_0[1][sb] = slope_0[2][sb] =
 629                         adec_scalefactor_table[index_0];
 630                 }
 631                 else
 632                 {
 633                     float scalefactor;
 634                     float slope, offset;
 635
 636                     slope = adec_slope_table[allocation_0[sb]-2];
 637                     offset = adec_offset_table[allocation_0[sb]-2];
 638
 639                     scalefactor = adec_scalefactor_table[index_0];
 640                     slope_0[0][sb] = slope_0[1][sb] = slope_0[2][sb] =
 641                         slope * scalefactor;
 642                     offset_0[0][sb] = offset_0[1][sb] = offset_0[2][sb] =
 643                         offset * scalefactor;
 644                 }
 645                 break;
 646
 647             case 3:
 648                 index_0 = GetBits(&p_adec->bit_stream,6);
 649                 index_1 = GetBits(&p_adec->bit_stream,6);
 650                 i_read_bits += 12;
 651
 652                 if (allocation_0[sb] < 0)
 653                 {
 654                     slope_0[0][sb] = adec_scalefactor_table[index_0];
 655                     slope_0[1][sb] = slope_0[2][sb] =
 656                         adec_scalefactor_table[index_1];
 657                 }
 658                 else
 659                 {
 660                     float scalefactor;
 661                     float slope, offset;
 662
 663                     slope = adec_slope_table[allocation_0[sb]-2];
 664                     offset = adec_offset_table[allocation_0[sb]-2];
 665
 666                     scalefactor = adec_scalefactor_table[index_0];
 667                     slope_0[0][sb] = slope * scalefactor;
 668                     offset_0[0][sb] = offset * scalefactor;
 669
 670                     scalefactor = adec_scalefactor_table[index_1];
 671                     slope_0[1][sb] = slope_0[2][sb] = slope * scalefactor;
 672                     offset_0[1][sb] = offset_0[2][sb] =
 673                         offset * scalefactor;
 674                 }
 675                 break;
 676             }
 677         }
 678
 679         if (allocation_1[sb])
 680         {
 681             int index_0, index_1, index_2;
 682
 683             switch (scfsi_1[sb])
 684             {
 685             case 0:
 686                 index_0 = GetBits(&p_adec->bit_stream,6);
 687                 index_1 = GetBits(&p_adec->bit_stream,6);
 688                 index_2 = GetBits(&p_adec->bit_stream,6);
 689                 i_read_bits += 18;
 690
 691                 if (allocation_1[sb] < 0)
 692                 {
 693                     slope_1[0][sb] = adec_scalefactor_table[index_0];
 694                     slope_1[1][sb] = adec_scalefactor_table[index_1];
 695                     slope_1[2][sb] = adec_scalefactor_table[index_2];
 696                 }
 697                 else
 698                 {
 699                     float scalefactor;
 700                     float slope, offset;
 701
 702                     slope = adec_slope_table[allocation_1[sb]-2];
 703                     offset = adec_offset_table[allocation_1[sb]-2];
 704
 705                     scalefactor = adec_scalefactor_table[index_0];
 706                     slope_1[0][sb] = slope * scalefactor;
 707                     offset_1[0][sb] = offset * scalefactor;
 708
 709                     scalefactor = adec_scalefactor_table[index_1];
 710                     slope_1[1][sb] = slope * scalefactor;
 711                     offset_1[1][sb] = offset * scalefactor;
 712
 713                     scalefactor = adec_scalefactor_table[index_2];
 714                     slope_1[2][sb] = slope * scalefactor;
 715                     offset_1[2][sb] = offset * scalefactor;
 716                 }
 717                 break;
 718
 719             case 1:
 720                 index_0 = GetBits(&p_adec->bit_stream,6);
 721                 index_1 = GetBits(&p_adec->bit_stream,6);
 722                 i_read_bits += 12;
 723
 724                 if (allocation_1[sb] < 0)
 725                 {
 726                     slope_1[0][sb] = slope_1[1][sb] =
 727                         adec_scalefactor_table[index_0];
 728                     slope_1[2][sb] = adec_scalefactor_table[index_1];
 729                 }
 730                 else
 731                 {
 732                     float scalefactor;
 733                     float slope, offset;
 734
 735                     slope = adec_slope_table[allocation_1[sb]-2];
 736                     offset = adec_offset_table[allocation_1[sb]-2];
 737
 738                     scalefactor = adec_scalefactor_table[index_0];
 739                     slope_1[0][sb] = slope_1[1][sb] = slope * scalefactor;
 740                     offset_1[0][sb] = offset_1[1][sb] =
 741                         offset * scalefactor;
 742
 743                     scalefactor = adec_scalefactor_table[index_1];
 744                     slope_1[2][sb] = slope * scalefactor;
 745                     offset_1[2][sb] = offset * scalefactor;
 746                 }
 747                 break;
 748
 749             case 2:
 750                 index_0 = GetBits( &p_adec->bit_stream, 6 );
 751                 i_read_bits += 6;
 752
 753                 if (allocation_1[sb] < 0)
 754                 {
 755                     slope_1[0][sb] = slope_1[1][sb] = slope_1[2][sb] =
 756                         adec_scalefactor_table[index_0];
 757                 }
 758                 else
 759                 {
 760                     float scalefactor;
 761                     float slope, offset;
 762
 763                     slope = adec_slope_table[allocation_1[sb]-2];
 764                     offset = adec_offset_table[allocation_1[sb]-2];
 765
 766                     scalefactor = adec_scalefactor_table[index_0];
 767                     slope_1[0][sb] = slope_1[1][sb] = slope_1[2][sb] =
 768                         slope * scalefactor;
 769                     offset_1[0][sb] = offset_1[1][sb] = offset_1[2][sb] =
 770                         offset * scalefactor;
 771                 }
 772                 break;
 773
 774             case 3:
 775                 index_0 = GetBits(&p_adec->bit_stream,6);
 776                 index_1 = GetBits(&p_adec->bit_stream,6);
 777                 i_read_bits += 12;
 778
 779                 if (allocation_1[sb] < 0)
 780                 {
 781                     slope_1[0][sb] = adec_scalefactor_table[index_0];
 782                     slope_1[1][sb] = slope_1[2][sb] =
 783                         adec_scalefactor_table[index_1];
 784                 }
 785                 else
 786                 {
 787                     float scalefactor;
 788                     float slope, offset;
 789
 790                     slope = adec_slope_table[allocation_1[sb]-2];
 791                     offset = adec_offset_table[allocation_1[sb]-2];
 792
 793                     scalefactor = adec_scalefactor_table[index_0];
 794                     slope_1[0][sb] = slope * scalefactor;
 795                     offset_1[0][sb] = offset * scalefactor;
 796
 797                     scalefactor = adec_scalefactor_table[index_1];
 798                     slope_1[1][sb] = slope_1[2][sb] = slope * scalefactor;
 799                     offset_1[1][sb] = offset_1[2][sb] =
 800                         offset * scalefactor;
 801                 }
 802                 break;
 803             }
 804         }
 805     }
 806
 807     /* parse samples */
 808
 809     for (gr0 = 0; gr0 < 3; gr0++)
 810     {
 811         for (gr1 = 0; gr1 < 4; gr1++)
 812         {
 813             s16 * XXX_buf;
 814
 815             for (sb = 0; sb < bound; sb++)
 816             {
 817                 int code;
 818
 819                 switch (allocation_0[sb])
 820                 {
 821                     case 0:
 822                         sample_0[0][sb] = sample_0[1][sb] = sample_0[2][sb] = 0;
 823                         break;
 824
 825                     case L3:
 826                         code = GetBits( &p_adec->bit_stream, 5 );
 827                         i_read_bits += 5;
 828
 829                         sample_0[0][sb] = slope_0[gr0][sb] * L3_table[code % 3];
 830                         code /= 3;
 831                         sample_0[1][sb] = slope_0[gr0][sb] * L3_table[code % 3];
 832                         code /= 3;
 833                         sample_0[2][sb] = slope_0[gr0][sb] * L3_table[code];
 834                     break;
 835
 836                     case L5:
 837                         code = GetBits( &p_adec->bit_stream, 7 );
 838                         i_read_bits += 7;
 839
 840                         sample_0[0][sb] = slope_0[gr0][sb] * L5_table[code % 5];
 841                         code /= 5;
 842                         sample_0[1][sb] = slope_0[gr0][sb] * L5_table[code % 5];
 843                         code /= 5;
 844                         sample_0[2][sb] = slope_0[gr0][sb] * L5_table[code];
 845                     break;
 846
 847                     case L9:
 848                         code = GetBits( &p_adec->bit_stream, 10 );
 849                         i_read_bits += 10;
 850
 851                         sample_0[0][sb] = slope_0[gr0][sb] * L9_table[code % 9];
 852                         code /= 9;
 853                         sample_0[1][sb] = slope_0[gr0][sb] * L9_table[code % 9];
 854                         code /= 9;
 855                         sample_0[2][sb] = slope_0[gr0][sb] * L9_table[code];
 856                     break;
 857
 858                     default:
 859                         for (s = 0; s < 3; s++)
 860                         {
 861                             code = GetBits( &p_adec->bit_stream,
 862                                             allocation_0[sb] );
 863                             i_read_bits += allocation_0[sb];
 864
 865                             sample_0[s][sb] =
 866                                 slope_0[gr0][sb] * code + offset_0[gr0][sb];
 867                         }
 868                 }
 869
 870                 switch (allocation_1[sb])
 871                 {
 872                     case 0:
 873                         sample_1[0][sb] = sample_1[1][sb] = sample_1[2][sb] = 0;
 874                     break;
 875
 876                     case L3:
 877                         code = GetBits( &p_adec->bit_stream, 5 );
 878                         i_read_bits += 5;
 879
 880                         sample_1[0][sb] = slope_1[gr0][sb] * L3_table[code % 3];
 881                         code /= 3;
 882                         sample_1[1][sb] = slope_1[gr0][sb] * L3_table[code % 3];
 883                         code /= 3;
 884                         sample_1[2][sb] = slope_1[gr0][sb] * L3_table[code];
 885                     break;
 886
 887                     case L5:
 888                         code = GetBits( &p_adec->bit_stream, 7 );
 889                         i_read_bits += 7;
 890
 891                         sample_1[0][sb] = slope_1[gr0][sb] * L5_table[code % 5];
 892                         code /= 5;
 893                         sample_1[1][sb] = slope_1[gr0][sb] * L5_table[code % 5];
 894                         code /= 5;
 895                         sample_1[2][sb] = slope_1[gr0][sb] * L5_table[code];
 896                     break;
 897
 898                     case L9:
 899                         code = GetBits( &p_adec->bit_stream, 10 );
 900                         i_read_bits += 10;
 901
 902                         sample_1[0][sb] = slope_1[gr0][sb] * L9_table[code % 9];
 903                         code /= 9;
 904                         sample_1[1][sb] = slope_1[gr0][sb] * L9_table[code % 9];
 905                         code /= 9;
 906                         sample_1[2][sb] = slope_1[gr0][sb] * L9_table[code];
 907                     break;
 908
 909                     default:
 910                         for (s = 0; s < 3; s++)
 911                         {
 912                             code = GetBits( &p_adec->bit_stream,
 913                                             allocation_1[sb] );
 914                             i_read_bits += allocation_1[sb];
 915
 916                             sample_1[s][sb] =
 917                                 slope_1[gr0][sb] * code + offset_1[gr0][sb];
 918                         }
 919                 }
 920             }
 921
 922             for (; sb < sblimit; sb++)
 923             {
 924                 int code;
 925
 926                 switch (allocation_0[sb])
 927                 {
 928                     case 0:
 929                         sample_0[0][sb] = sample_0[1][sb] = sample_0[2][sb] = 0;
 930                         sample_1[0][sb] = sample_1[1][sb] = sample_1[2][sb] = 0;
 931                     break;
 932
 933                     case L3:
 934                         code = GetBits( &p_adec->bit_stream, 5 );
 935                         i_read_bits += 5;
 936
 937                         sample_0[0][sb] = slope_0[gr0][sb] * L3_table[code % 3];
 938                         sample_1[0][sb] = slope_1[gr0][sb] * L3_table[code % 3];
 939                         code /= 3;
 940                         sample_0[1][sb] = slope_0[gr0][sb] * L3_table[code % 3];
 941                         sample_1[1][sb] = slope_1[gr0][sb] * L3_table[code % 3];
 942                         code /= 3;
 943                         sample_0[2][sb] = slope_0[gr0][sb] * L3_table[code];
 944                         sample_1[2][sb] = slope_1[gr0][sb] * L3_table[code];
 945                     break;
 946
 947                     case L5:
 948                         code = GetBits( &p_adec->bit_stream, 7 );
 949                         i_read_bits += 7;
 950
 951                         sample_0[0][sb] = slope_0[gr0][sb] * L5_table[code % 5];
 952                         sample_1[0][sb] = slope_1[gr0][sb] * L5_table[code % 5];
 953                         code /= 5;
 954                         sample_0[1][sb] = slope_0[gr0][sb] * L5_table[code % 5];
 955                         sample_1[1][sb] = slope_1[gr0][sb] * L5_table[code % 5];
 956                         code /= 5;
 957                         sample_0[2][sb] = slope_0[gr0][sb] * L5_table[code];
 958                         sample_1[2][sb] = slope_1[gr0][sb] * L5_table[code];
 959                     break;
 960
 961                     case L9:
 962                         code = GetBits( &p_adec->bit_stream, 10 );
 963                         i_read_bits += 10;
 964
 965                         sample_0[0][sb] = slope_0[gr0][sb] * L9_table[code % 9];
 966                         sample_1[0][sb] = slope_1[gr0][sb] * L9_table[code % 9];
 967                         code /= 9;
 968                         sample_0[1][sb] = slope_0[gr0][sb] * L9_table[code % 9];
 969                         sample_1[1][sb] = slope_1[gr0][sb] * L9_table[code % 9];
 970                         code /= 9;
 971                         sample_0[2][sb] = slope_0[gr0][sb] * L9_table[code];
 972                         sample_1[2][sb] = slope_1[gr0][sb] * L9_table[code];
 973                     break;
 974
 975                     default:
 976                         for (s = 0; s < 3; s++)
 977                         {
 978                             code = GetBits( &p_adec->bit_stream,
 979                                             allocation_0[sb] );
 980                             i_read_bits += allocation_0[sb];
 981
 982                             sample_0[s][sb] =
 983                                 slope_0[gr0][sb] * code + offset_0[gr0][sb];
 984                             sample_1[s][sb] =
 985                                 slope_1[gr0][sb] * code + offset_1[gr0][sb];
 986                         }
 987                 }
 988             }
 989
 990             for (; sb < 32; sb++)
 991             {
 992                 sample_0[0][sb] = sample_0[1][sb] = sample_0[2][sb] = 0;
 993                 sample_1[0][sb] = sample_1[1][sb] = sample_1[2][sb] = 0;
 994             }
 995
 996             for (s = 0; s < 3; s++)
 997             {
 998                 DCT32 (sample_0[s], &p_adec->bank_0);
 999                 XXX_buf = buffer;
1000                 PCM (&p_adec->bank_0, &XXX_buf, 2);
1001
1002                 DCT32 (sample_1[s], &p_adec->bank_1);
1003                 XXX_buf = buffer+1;
1004                 PCM (&p_adec->bank_1, &XXX_buf, 2);
1005
1006                 buffer += 64;
1007             }
1008         }
1009     }
1010
1011     p_adec->i_read_bits += i_read_bits;
1012
1013     return 0;
1014 }
1015