mp3lib/layer3.c

   1 /*
   2  * Modified for use with MPlayer, for details see the changelog at
   3  * http://svn.mplayerhq.hu/mplayer/trunk/
   4  * $Id$
   5  */
   6
   7 /*
   8  * Mpeg Layer-3 audio decoder
   9  * --------------------------
  10  * copyright (c) 1995-1999 by Michael Hipp.
  11  * All rights reserved. See also 'README'
  12  *
  13  * Optimize-TODO: put short bands into the band-field without the stride
  14  *                of 3 reals
  15  * Length-optimze: unify long and short band code where it is possible
  16  */
  17
  18 #include "mpg123.h"
  19
  20 #if 0
  21 #define L3_DEBUG 1
  22 #endif
  23
  24 #if 0
  25 #define CUT_HF
  26 #endif
  27
  28 #define REAL_MUL(x, y) ((x) * (y))
  29
  30 static real ispow[8207];
  31 static real aa_ca[8],aa_cs[8];
  32 static real COS1[12][6];
  33 static real win[4][36];
  34 static real win1[4][36];
  35 static real gainpow2[256+118+4];
  36
  37 /* non static for external 3dnow functions */
  38 real   COS9[9];
  39 static real COS6_1,COS6_2;
  40 real   tfcos36[9];
  41
  42 static real tfcos12[3];
  43 #define NEW_DCT9
  44 #ifdef NEW_DCT9
  45 static real cos9[3],cos18[3];
  46 #endif
  47
  48 struct bandInfoStruct {
  49   uint16_t longIdx[23];
  50   uint8_t  longDiff[22];
  51   uint16_t shortIdx[14];
  52   uint8_t  shortDiff[13];
  53 };
  54
  55 static int longLimit[9][23];
  56 static int shortLimit[9][14];
  57
  58 static const struct bandInfoStruct bandInfo[9] = {
  59
  60 /* MPEG 1.0 */
  61  { {0,4,8,12,16,20,24,30,36,44,52,62,74, 90,110,134,162,196,238,288,342,418,576},
  62    {4,4,4,4,4,4,6,6,8, 8,10,12,16,20,24,28,34,42,50,54, 76,158},
  63    {0,4*3,8*3,12*3,16*3,22*3,30*3,40*3,52*3,66*3, 84*3,106*3,136*3,192*3},
  64    {4,4,4,4,6,8,10,12,14,18,22,30,56} } ,
  65
  66  { {0,4,8,12,16,20,24,30,36,42,50,60,72, 88,106,128,156,190,230,276,330,384,576},
  67    {4,4,4,4,4,4,6,6,6, 8,10,12,16,18,22,28,34,40,46,54, 54,192},
  68    {0,4*3,8*3,12*3,16*3,22*3,28*3,38*3,50*3,64*3, 80*3,100*3,126*3,192*3},
  69    {4,4,4,4,6,6,10,12,14,16,20,26,66} } ,
  70
  71  { {0,4,8,12,16,20,24,30,36,44,54,66,82,102,126,156,194,240,296,364,448,550,576} ,
  72    {4,4,4,4,4,4,6,6,8,10,12,16,20,24,30,38,46,56,68,84,102, 26} ,
  73    {0,4*3,8*3,12*3,16*3,22*3,30*3,42*3,58*3,78*3,104*3,138*3,180*3,192*3} ,
  74    {4,4,4,4,6,8,12,16,20,26,34,42,12} }  ,
  75
  76 /* MPEG 2.0 */
  77  { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
  78    {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54 } ,
  79    {0,4*3,8*3,12*3,18*3,24*3,32*3,42*3,56*3,74*3,100*3,132*3,174*3,192*3} ,
  80    {4,4,4,6,6,8,10,14,18,26,32,42,18 } } ,
  81 /* changed 19th value fropm 330 to 332 */
  82  { {0,6,12,18,24,30,36,44,54,66,80,96,114,136,162,194,232,278,332,394,464,540,576},
  83    {6,6,6,6,6,6,8,10,12,14,16,18,22,26,32,38,46,54,62,70,76,36 } ,
  84    {0,4*3,8*3,12*3,18*3,26*3,36*3,48*3,62*3,80*3,104*3,136*3,180*3,192*3} ,
  85    {4,4,4,6,8,10,12,14,18,24,32,44,12 } } ,
  86
  87  { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
  88    {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54 },
  89    {0,4*3,8*3,12*3,18*3,26*3,36*3,48*3,62*3,80*3,104*3,134*3,174*3,192*3},
  90    {4,4,4,6,8,10,12,14,18,24,30,40,18 } } ,
  91 /* MPEG 2.5 */
  92  { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576} ,
  93    {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54},
  94    {0,12,24,36,54,78,108,144,186,240,312,402,522,576},
  95    {4,4,4,6,8,10,12,14,18,24,30,40,18} },
  96  { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576} ,
  97    {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54},
  98    {0,12,24,36,54,78,108,144,186,240,312,402,522,576},
  99    {4,4,4,6,8,10,12,14,18,24,30,40,18} },
 100  { {0,12,24,36,48,60,72,88,108,132,160,192,232,280,336,400,476,566,568,570,572,574,576},
 101    {12,12,12,12,12,12,16,20,24,28,32,40,48,56,64,76,90,2,2,2,2,2},
 102    {0, 24, 48, 72,108,156,216,288,372,480,486,492,498,576},
 103    {8,8,8,12,16,20,24,28,36,2,2,2,26} } ,
 104 };
 105
 106 static int mapbuf0[9][152];
 107 static int mapbuf1[9][156];
 108 static int mapbuf2[9][44];
 109 static int *map[9][3];
 110 static int *mapend[9][3];
 111
 112 static unsigned int n_slen2[512]; /* MPEG 2.0 slen for 'normal' mode */
 113 static unsigned int i_slen2[256]; /* MPEG 2.0 slen for intensity stereo */
 114
 115 static real tan1_1[16],tan2_1[16],tan1_2[16],tan2_2[16];
 116 static real pow1_1[2][16],pow2_1[2][16],pow1_2[2][16],pow2_2[2][16];
 117
 118 /*
 119  * init tables for layer-3
 120  */
 121 static void init_layer3(int down_sample_sblimit)
 122 {
 123   int i,j,k,l;
 124
 125   for(i=-256;i<118+4;i++)
 126   {
 127     if(_has_mmx)
 128       gainpow2[i+256] = 16384.0 * pow((double)2.0,-0.25 * (double) (i+210) );
 129     else
 130       gainpow2[i+256] = pow((double)2.0,-0.25 * (double) (i+210) );
 131   }
 132   for(i=0;i<8207;i++)
 133     ispow[i] = pow((double)i,(double)4.0/3.0);
 134
 135   for (i=0;i<8;i++)
 136   {
 137     static const double Ci[8]={-0.6,-0.535,-0.33,-0.185,-0.095,-0.041,-0.0142,-0.0037};
 138     double sq=sqrt(1.0+Ci[i]*Ci[i]);
 139     aa_cs[i] = 1.0/sq;
 140     aa_ca[i] = Ci[i]/sq;
 141   }
 142
 143   for(i=0;i<18;i++)
 144   {
 145     win[0][i]    = win[1][i]    = 0.5 * sin( M_PI / 72.0 * (double) (2*(i+0) +1) ) / cos ( M_PI * (double) (2*(i+0) +19) / 72.0 );
 146     win[0][i+18] = win[3][i+18] = 0.5 * sin( M_PI / 72.0 * (double) (2*(i+18)+1) ) / cos ( M_PI * (double) (2*(i+18)+19) / 72.0 );
 147   }
 148   for(i=0;i<6;i++)
 149   {
 150     win[1][i+18] = 0.5 / cos ( M_PI * (double) (2*(i+18)+19) / 72.0 );
 151     win[3][i+12] = 0.5 / cos ( M_PI * (double) (2*(i+12)+19) / 72.0 );
 152     win[1][i+24] = 0.5 * sin( M_PI / 24.0 * (double) (2*i+13) ) / cos ( M_PI * (double) (2*(i+24)+19) / 72.0 );
 153     win[1][i+30] = win[3][i] = 0.0;
 154     win[3][i+6 ] = 0.5 * sin( M_PI / 24.0 * (double) (2*i+1) )  / cos ( M_PI * (double) (2*(i+6 )+19) / 72.0 );
 155   }
 156
 157   for(i=0;i<9;i++)
 158     COS9[i] = cos( M_PI / 18.0 * (double) i);
 159
 160   for(i=0;i<9;i++)
 161     tfcos36[i] = 0.5 / cos ( M_PI * (double) (i*2+1) / 36.0 );
 162   for(i=0;i<3;i++)
 163     tfcos12[i] = 0.5 / cos ( M_PI * (double) (i*2+1) / 12.0 );
 164
 165   COS6_1 = cos( M_PI / 6.0 * (double) 1);
 166   COS6_2 = cos( M_PI / 6.0 * (double) 2);
 167
 168 #ifdef NEW_DCT9
 169   cos9[0] = cos(1.0*M_PI/9.0);
 170   cos9[1] = cos(5.0*M_PI/9.0);
 171   cos9[2] = cos(7.0*M_PI/9.0);
 172   cos18[0] = cos(1.0*M_PI/18.0);
 173   cos18[1] = cos(11.0*M_PI/18.0);
 174   cos18[2] = cos(13.0*M_PI/18.0);
 175 #endif
 176
 177   for(i=0;i<12;i++)
 178   {
 179     win[2][i]  = 0.5 * sin( M_PI / 24.0 * (double) (2*i+1) ) / cos ( M_PI * (double) (2*i+7) / 24.0 );
 180     for(j=0;j<6;j++)
 181       COS1[i][j] = cos( M_PI / 24.0 * (double) ((2*i+7)*(2*j+1)) );
 182   }
 183
 184   for(j=0;j<4;j++) {
 185     static const int len[4] = { 36,36,12,36 };
 186     for(i=0;i<len[j];i+=2)
 187       win1[j][i] = + win[j][i];
 188     for(i=1;i<len[j];i+=2)
 189       win1[j][i] = - win[j][i];
 190   }
 191
 192   for(i=0;i<16;i++)
 193   {
 194     double t = tan( (double) i * M_PI / 12.0 );
 195     tan1_1[i] = t / (1.0+t);
 196     tan2_1[i] = 1.0 / (1.0 + t);
 197     tan1_2[i] = M_SQRT2 * t / (1.0+t);
 198     tan2_2[i] = M_SQRT2 / (1.0 + t);
 199
 200     for(j=0;j<2;j++) {
 201       double base = pow(2.0,-0.25*(j+1.0));
 202       double p1=1.0,p2=1.0;
 203       if(i > 0) {
 204         if( i & 1 )
 205           p1 = pow(base,(i+1.0)*0.5);
 206         else
 207           p2 = pow(base,i*0.5);
 208       }
 209       pow1_1[j][i] = p1;
 210       pow2_1[j][i] = p2;
 211       pow1_2[j][i] = M_SQRT2 * p1;
 212       pow2_2[j][i] = M_SQRT2 * p2;
 213     }
 214   }
 215
 216   for(j=0;j<9;j++)
 217   {
 218    const struct bandInfoStruct *bi = &bandInfo[j];
 219    int *mp;
 220    int cb,lwin;
 221    const uint8_t *bdf;
 222
 223    mp = map[j][0] = mapbuf0[j];
 224    bdf = bi->longDiff;
 225    for(i=0,cb = 0; cb < 8 ; cb++,i+=*bdf++) {
 226      *mp++ = (*bdf) >> 1;
 227      *mp++ = i;
 228      *mp++ = 3;
 229      *mp++ = cb;
 230    }
 231    bdf = bi->shortDiff+3;
 232    for(cb=3;cb<13;cb++) {
 233      int l = (*bdf++) >> 1;
 234      for(lwin=0;lwin<3;lwin++) {
 235        *mp++ = l;
 236        *mp++ = i + lwin;
 237        *mp++ = lwin;
 238        *mp++ = cb;
 239      }
 240      i += 6*l;
 241    }
 242    mapend[j][0] = mp;
 243
 244    mp = map[j][1] = mapbuf1[j];
 245    bdf = bi->shortDiff+0;
 246    for(i=0,cb=0;cb<13;cb++) {
 247      int l = (*bdf++) >> 1;
 248      for(lwin=0;lwin<3;lwin++) {
 249        *mp++ = l;
 250        *mp++ = i + lwin;
 251        *mp++ = lwin;
 252        *mp++ = cb;
 253      }
 254      i += 6*l;
 255    }
 256    mapend[j][1] = mp;
 257
 258    mp = map[j][2] = mapbuf2[j];
 259    bdf = bi->longDiff;
 260    for(cb = 0; cb < 22 ; cb++) {
 261      *mp++ = (*bdf++) >> 1;
 262      *mp++ = cb;
 263    }
 264    mapend[j][2] = mp;
 265
 266   }
 267
 268   for(j=0;j<9;j++) {
 269     for(i=0;i<23;i++) {
 270       longLimit[j][i] = (bandInfo[j].longIdx[i] - 1 + 8) / 18 + 1;
 271       if(longLimit[j][i] > (down_sample_sblimit) )
 272         longLimit[j][i] = down_sample_sblimit;
 273     }
 274     for(i=0;i<14;i++) {
 275       shortLimit[j][i] = (bandInfo[j].shortIdx[i] - 1) / 18 + 1;
 276       if(shortLimit[j][i] > (down_sample_sblimit) )
 277         shortLimit[j][i] = down_sample_sblimit;
 278     }
 279   }
 280
 281   for(i=0;i<5;i++) {
 282     for(j=0;j<6;j++) {
 283       for(k=0;k<6;k++) {
 284         int n = k + j * 6 + i * 36;
 285         i_slen2[n] = i|(j<<3)|(k<<6)|(3<<12);
 286       }
 287     }
 288   }
 289   for(i=0;i<4;i++) {
 290     for(j=0;j<4;j++) {
 291       for(k=0;k<4;k++) {
 292         int n = k + j * 4 + i * 16;
 293         i_slen2[n+180] = i|(j<<3)|(k<<6)|(4<<12);
 294       }
 295     }
 296   }
 297   for(i=0;i<4;i++) {
 298     for(j=0;j<3;j++) {
 299       int n = j + i * 3;
 300       i_slen2[n+244] = i|(j<<3) | (5<<12);
 301       n_slen2[n+500] = i|(j<<3) | (2<<12) | (1<<15);
 302     }
 303   }
 304
 305   for(i=0;i<5;i++) {
 306     for(j=0;j<5;j++) {
 307       for(k=0;k<4;k++) {
 308         for(l=0;l<4;l++) {
 309           int n = l + k * 4 + j * 16 + i * 80;
 310           n_slen2[n] = i|(j<<3)|(k<<6)|(l<<9)|(0<<12);
 311         }
 312       }
 313     }
 314   }
 315   for(i=0;i<5;i++) {
 316     for(j=0;j<5;j++) {
 317       for(k=0;k<4;k++) {
 318         int n = k + j * 4 + i * 20;
 319         n_slen2[n+400] = i|(j<<3)|(k<<6)|(1<<12);
 320       }
 321     }
 322   }
 323 }
 324
 325 /*
 326  * read additional side information (for MPEG 1 and MPEG 2)
 327  */
 328 static int III_get_side_info(struct III_sideinfo *si,int stereo,
 329  int ms_stereo,int sfreq,int single,int lsf)
 330 {
 331    int ch, gr;
 332    int powdiff = (single == 3) ? 4 : 0;
 333
 334    static const int tabs[2][5] = { { 2,9,5,3,4 } , { 1,8,1,2,9 } };
 335    const int *tab = tabs[lsf];
 336
 337    si->main_data_begin = getbits(tab[1]);
 338    if (stereo == 1)
 339      si->private_bits = getbits_fast(tab[2]);
 340    else
 341      si->private_bits = getbits_fast(tab[3]);
 342
 343    if(!lsf) {
 344      for (ch=0; ch<stereo; ch++) {
 345          si->ch[ch].gr[0].scfsi = -1;
 346          si->ch[ch].gr[1].scfsi = getbits_fast(4);
 347      }
 348    }
 349
 350    for (gr=0; gr<tab[0]; gr++) {
 351      for (ch=0; ch<stereo; ch++) {
 352        register struct gr_info_s *gr_info = &(si->ch[ch].gr[gr]);
 353
 354        gr_info->part2_3_length = getbits(12);
 355        gr_info->big_values = getbits(9);
 356        if(gr_info->big_values > 288) {
 357             fprintf(stderr,"big_values too large!\n");
 358           gr_info->big_values = 288;
 359        }
 360        gr_info->pow2gain = gainpow2+256 - getbits_fast(8) + powdiff;
 361        if(ms_stereo)
 362          gr_info->pow2gain += 2;
 363        gr_info->scalefac_compress = getbits(tab[4]);
 364
 365        if(get1bit()) { /* window switch flag  */
 366          int i;
 367 #ifdef L3_DEBUG
 368 if(2*gr_info->big_values > bandInfo[sfreq].shortIdx[12])
 369   fprintf(stderr,"L3: BigValues too large, doesn't make sense %d %d\n",2*gr_info->big_values,bandInfo[sfreq].shortIdx[12]);
 370 #endif
 371
 372          gr_info->block_type       = getbits_fast(2);
 373          gr_info->mixed_block_flag = get1bit();
 374          gr_info->table_select[0]  = getbits_fast(5);
 375          gr_info->table_select[1]  = getbits_fast(5);
 376          /*
 377           * table_select[2] not needed, because there is no region2,
 378           * but to satisfy some verifications tools we set it either.
 379           */
 380          gr_info->table_select[2] = 0;
 381          for(i=0;i<3;i++)
 382            gr_info->full_gain[i] = gr_info->pow2gain + (getbits_fast(3)<<3);
 383
 384          if(gr_info->block_type == 0) {
 385              fprintf(stderr,"Blocktype == 0 and window-switching == 1 not allowed.\n");
 386            return 0;
 387          }
 388
 389          /* region_count/start parameters are implicit in this case. */
 390          if(!lsf || gr_info->block_type == 2)
 391            gr_info->region1start = 36>>1;
 392          else {
 393 /* check this again for 2.5 and sfreq=8 */
 394            if(sfreq == 8)
 395              gr_info->region1start = 108>>1;
 396            else
 397              gr_info->region1start = 54>>1;
 398          }
 399          gr_info->region2start = 576>>1;
 400        }
 401        else {
 402          int i,r0c,r1c;
 403 #ifdef L3_DEBUG
 404 if(2*gr_info->big_values > bandInfo[sfreq].longIdx[21])
 405   fprintf(stderr,"L3: BigValues too large, doesn't make sense %d %d\n",2*gr_info->big_values,bandInfo[sfreq].longIdx[21]);
 406 #endif
 407          for (i=0; i<3; i++)
 408            gr_info->table_select[i] = getbits_fast(5);
 409          r0c = getbits_fast(4);
 410          r1c = getbits_fast(3);
 411          gr_info->region1start = bandInfo[sfreq].longIdx[r0c+1] >> 1 ;
 412          if(r0c + r1c + 2 > 22)
 413            gr_info->region2start = 576>>1;
 414          else
 415            gr_info->region2start = bandInfo[sfreq].longIdx[r0c+1+r1c+1] >> 1;
 416          gr_info->block_type = 0;
 417          gr_info->mixed_block_flag = 0;
 418        }
 419        if(!lsf)
 420          gr_info->preflag = get1bit();
 421        gr_info->scalefac_scale = get1bit();
 422        gr_info->count1table_select = get1bit();
 423      }
 424    }
 425
 426    return !0;
 427 }
 428
 429 /*
 430  * read scalefactors
 431  */
 432 static int III_get_scale_factors_1(int *scf,struct gr_info_s *gr_info)
 433 {
 434    static const unsigned char slen[2][16] = {
 435      {0, 0, 0, 0, 3, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4},
 436      {0, 1, 2, 3, 0, 1, 2, 3, 1, 2, 3, 1, 2, 3, 2, 3}
 437    };
 438    int numbits;
 439    int num0 = slen[0][gr_info->scalefac_compress];
 440    int num1 = slen[1][gr_info->scalefac_compress];
 441
 442     if (gr_info->block_type == 2) {
 443       int i=18;
 444       numbits = (num0 + num1) * 18;
 445
 446       if (gr_info->mixed_block_flag) {
 447          for (i=8;i;i--)
 448            *scf++ = getbits_fast(num0);
 449          i = 9;
 450          numbits -= num0; /* num0 * 17 + num1 * 18 */
 451       }
 452
 453       for (;i;i--)
 454         *scf++ = getbits_fast(num0);
 455       for (i = 18; i; i--)
 456         *scf++ = getbits_fast(num1);
 457       *scf++ = 0; *scf++ = 0; *scf++ = 0; /* short[13][0..2] = 0 */
 458     }
 459     else {
 460       int i;
 461       int scfsi = gr_info->scfsi;
 462
 463       if(scfsi < 0) { /* scfsi < 0 => granule == 0 */
 464          for(i=11;i;i--)
 465            *scf++ = getbits_fast(num0);
 466          for(i=10;i;i--)
 467            *scf++ = getbits_fast(num1);
 468          numbits = (num0 + num1) * 10 + num0;
 469          *scf++ = 0;
 470       }
 471       else {
 472         numbits = 0;
 473         if(!(scfsi & 0x8)) {
 474           for (i=0;i<6;i++)
 475             *scf++ = getbits_fast(num0);
 476           numbits += num0 * 6;
 477         }
 478         else {
 479           scf += 6;
 480         }
 481
 482         if(!(scfsi & 0x4)) {
 483           for (i=0;i<5;i++)
 484             *scf++ = getbits_fast(num0);
 485           numbits += num0 * 5;
 486         }
 487         else {
 488           scf += 5;
 489         }
 490
 491         if(!(scfsi & 0x2)) {
 492           for(i=0;i<5;i++)
 493             *scf++ = getbits_fast(num1);
 494           numbits += num1 * 5;
 495         }
 496         else {
 497           scf += 5;
 498         }
 499
 500         if(!(scfsi & 0x1)) {
 501           for (i=0;i<5;i++)
 502             *scf++ = getbits_fast(num1);
 503           numbits += num1 * 5;
 504         }
 505         else {
 506            scf += 5;
 507         }
 508         *scf++ = 0;  /* no l[21] in original sources */
 509       }
 510     }
 511     return numbits;
 512 }
 513
 514 static int III_get_scale_factors_2(int *scf,struct gr_info_s *gr_info,int i_stereo)
 515 {
 516   unsigned char *pnt;
 517   int i,j;
 518   unsigned int slen;
 519   int n = 0;
 520   int numbits = 0;
 521
 522   static unsigned char stab[3][6][4] = {
 523    { { 6, 5, 5,5 } , { 6, 5, 7,3 } , { 11,10,0,0} ,
 524      { 7, 7, 7,0 } , { 6, 6, 6,3 } , {  8, 8,5,0} } ,
 525    { { 9, 9, 9,9 } , { 9, 9,12,6 } , { 18,18,0,0} ,
 526      {12,12,12,0 } , {12, 9, 9,6 } , { 15,12,9,0} } ,
 527    { { 6, 9, 9,9 } , { 6, 9,12,6 } , { 15,18,0,0} ,
 528      { 6,15,12,0 } , { 6,12, 9,6 } , {  6,18,9,0} } };
 529
 530   if(i_stereo) /* i_stereo AND second channel -> do_layer3() checks this */
 531     slen = i_slen2[gr_info->scalefac_compress>>1];
 532   else
 533     slen = n_slen2[gr_info->scalefac_compress];
 534
 535   gr_info->preflag = (slen>>15) & 0x1;
 536
 537   n = 0;
 538   if( gr_info->block_type == 2 ) {
 539     n++;
 540     if(gr_info->mixed_block_flag) n++;
 541   }
 542
 543   pnt = stab[n][(slen>>12)&0x7];
 544
 545   for(i=0;i<4;i++) {
 546     int num = slen & 0x7;
 547     slen >>= 3;
 548     if(num) {
 549       for(j=0;j<(int)(pnt[i]);j++) *scf++ = getbits_fast(num);
 550       numbits += pnt[i] * num;
 551     }
 552     else {
 553       for(j=0;j<(int)(pnt[i]);j++) *scf++ = 0;
 554     }
 555   }
 556
 557   n = (n << 1) + 1;
 558   for(i=0;i<n;i++) *scf++ = 0;
 559
 560   return numbits;
 561 }
 562
 563 static int pretab1[22] = {0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,2,2,3,3,3,2,0};
 564 static int pretab2[22] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
 565
 566 #define getbitoffset() ((-bitindex)&0x7)
 567 #define getbyte()      (*wordpointer++)
 568
 569 /*
 570  * Dequantize samples (includes huffman decoding)
 571  */
 572 /* 24 is enough because tab13 has max. a 19 bit huffvector */
 573 #define BITSHIFT ((sizeof(long)-1)*8)
 574 #define REFRESH_MASK \
 575   while(num < BITSHIFT) { \
 576     mask |= ((unsigned long)getbyte())<<(BITSHIFT-num); \
 577     num += 8; \
 578     part2remain -= 8; }
 579
 580 static int III_dequantize_sample(real xr[SBLIMIT][SSLIMIT],int *scf,
 581    struct gr_info_s *gr_info,int sfreq,int part2bits)
 582 {
 583   int shift = 1 + gr_info->scalefac_scale;
 584   real *xrpnt = (real *) xr;
 585   int l[3],l3;
 586   int part2remain = gr_info->part2_3_length - part2bits;
 587   int *me;
 588
 589   int num=getbitoffset();
 590   long mask;
 591   /* we must split this, because for num==0 the shift is undefined if you do it in one step */
 592   mask  = ((unsigned long) getbits(num))<<BITSHIFT;
 593   mask <<= 8-num;
 594   part2remain -= num;
 595
 596   {
 597     int bv       = gr_info->big_values;
 598     int region1  = gr_info->region1start;
 599     int region2  = gr_info->region2start;
 600
 601     l3 = ((576>>1)-bv)>>1;
 602 /*
 603  * we may lose the 'odd' bit here !!
 604  * check this later again
 605  */
 606     if(bv <= region1) {
 607       l[0] = bv; l[1] = l[2] = 0;
 608     }
 609     else {
 610       l[0] = region1;
 611       if(bv <= region2) {
 612         l[1] = bv - l[0];  l[2] = 0;
 613       }
 614       else {
 615         l[1] = region2 - l[0]; l[2] = bv - region2;
 616       }
 617     }
 618   }
 619
 620   if(gr_info->block_type == 2) {
 621     /*
 622      * decoding with short or mixed mode BandIndex table
 623      */
 624     int i,max[4];
 625     int step=0,lwin=3,cb=0;
 626     register real v = 0.0;
 627     register int *m,mc;
 628
 629     if(gr_info->mixed_block_flag) {
 630       max[3] = -1;
 631       max[0] = max[1] = max[2] = 2;
 632       m = map[sfreq][0];
 633       me = mapend[sfreq][0];
 634     }
 635     else {
 636       max[0] = max[1] = max[2] = max[3] = -1;
 637       /* max[3] not really needed in this case */
 638       m = map[sfreq][1];
 639       me = mapend[sfreq][1];
 640     }
 641
 642     mc = 0;
 643     for(i=0;i<2;i++) {
 644       int lp = l[i];
 645       struct newhuff *h = ht+gr_info->table_select[i];
 646       for(;lp;lp--,mc--) {
 647         register int x,y;
 648         if( (!mc) ) {
 649           mc    = *m++;
 650           xrpnt = ((real *) xr) + (*m++);
 651           lwin  = *m++;
 652           cb    = *m++;
 653           if(lwin == 3) {
 654             v = gr_info->pow2gain[(*scf++) << shift];
 655             step = 1;
 656           }
 657           else {
 658             v = gr_info->full_gain[lwin][(*scf++) << shift];
 659             step = 3;
 660           }
 661         }
 662         {
 663           register short *val = h->table;
 664           REFRESH_MASK;
 665           while((y=*val++)<0) {
 666             if (mask < 0)
 667               val -= y;
 668             num--;
 669             mask <<= 1;
 670           }
 671           x = y >> 4;
 672           y &= 0xf;
 673         }
 674         if(x == 15 && h->linbits) {
 675           max[lwin] = cb;
 676           REFRESH_MASK;
 677           x += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
 678           num -= h->linbits+1;
 679           mask <<= h->linbits;
 680           if(mask < 0)
 681             *xrpnt = REAL_MUL(-ispow[x], v);
 682           else
 683             *xrpnt = REAL_MUL(ispow[x], v);
 684           mask <<= 1;
 685         }
 686         else if(x) {
 687           max[lwin] = cb;
 688           if(mask < 0)
 689             *xrpnt = REAL_MUL(-ispow[x], v);
 690           else
 691             *xrpnt = REAL_MUL(ispow[x], v);
 692           num--;
 693           mask <<= 1;
 694         }
 695         else
 696           *xrpnt = 0.0;
 697         xrpnt += step;
 698         if(y == 15 && h->linbits) {
 699           max[lwin] = cb;
 700           REFRESH_MASK;
 701           y += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
 702           num -= h->linbits+1;
 703           mask <<= h->linbits;
 704           if(mask < 0)
 705             *xrpnt = REAL_MUL(-ispow[y], v);
 706           else
 707             *xrpnt = REAL_MUL(ispow[y], v);
 708           mask <<= 1;
 709         }
 710         else if(y) {
 711           max[lwin] = cb;
 712           if(mask < 0)
 713             *xrpnt = REAL_MUL(-ispow[y], v);
 714           else
 715             *xrpnt = REAL_MUL(ispow[y], v);
 716           num--;
 717           mask <<= 1;
 718         }
 719         else
 720           *xrpnt = 0.0;
 721         xrpnt += step;
 722       }
 723     }
 724
 725     for(;l3 && (part2remain+num > 0);l3--) {
 726       struct newhuff *h = htc+gr_info->count1table_select;
 727       register short *val = h->table,a;
 728
 729       REFRESH_MASK;
 730       while((a=*val++)<0) {
 731         if (mask < 0)
 732           val -= a;
 733         num--;
 734         mask <<= 1;
 735       }
 736       if(part2remain+num <= 0) {
 737         num -= part2remain+num;
 738         break;
 739       }
 740
 741       for(i=0;i<4;i++) {
 742         if(!(i & 1)) {
 743           if(!mc) {
 744             mc = *m++;
 745             xrpnt = ((real *) xr) + (*m++);
 746             lwin = *m++;
 747             cb = *m++;
 748             if(lwin == 3) {
 749               v = gr_info->pow2gain[(*scf++) << shift];
 750               step = 1;
 751             }
 752             else {
 753               v = gr_info->full_gain[lwin][(*scf++) << shift];
 754               step = 3;
 755             }
 756           }
 757           mc--;
 758         }
 759         if( (a & (0x8>>i)) ) {
 760           max[lwin] = cb;
 761           if(part2remain+num <= 0) {
 762             break;
 763           }
 764           if(mask < 0)
 765             *xrpnt = -v;
 766           else
 767             *xrpnt = v;
 768           num--;
 769           mask <<= 1;
 770         }
 771         else
 772           *xrpnt = 0.0;
 773         xrpnt += step;
 774       }
 775     }
 776
 777     if(lwin < 3) { /* short band? */
 778       while(1) {
 779         for(;mc > 0;mc--) {
 780           *xrpnt = 0.0; xrpnt += 3; /* short band -> step=3 */
 781           *xrpnt = 0.0; xrpnt += 3;
 782         }
 783         if(m >= me)
 784           break;
 785         mc    = *m++;
 786         xrpnt = ((real *) xr) + *m++;
 787         if(*m++ == 0)
 788           break; /* optimize: field will be set to zero at the end of the function */
 789         m++; /* cb */
 790       }
 791     }
 792
 793     gr_info->maxband[0] = max[0]+1;
 794     gr_info->maxband[1] = max[1]+1;
 795     gr_info->maxband[2] = max[2]+1;
 796     gr_info->maxbandl = max[3]+1;
 797
 798     {
 799       int rmax = max[0] > max[1] ? max[0] : max[1];
 800       rmax = (rmax > max[2] ? rmax : max[2]) + 1;
 801       gr_info->maxb = rmax ? shortLimit[sfreq][rmax] : longLimit[sfreq][max[3]+1];
 802     }
 803
 804   }
 805   else {
 806     /*
 807      * decoding with 'long' BandIndex table (block_type != 2)
 808      */
 809     int *pretab = gr_info->preflag ? pretab1 : pretab2;
 810     int i,max = -1;
 811     int cb = 0;
 812     int *m = map[sfreq][2];
 813     register real v = 0.0;
 814     int mc = 0;
 815
 816     /*
 817      * long hash table values
 818      */
 819     for(i=0;i<3;i++) {
 820       int lp = l[i];
 821       struct newhuff *h = ht+gr_info->table_select[i];
 822
 823       for(;lp;lp--,mc--) {
 824         int x,y;
 825
 826         if(!mc) {
 827           mc = *m++;
 828           cb = *m++;
 829 #ifdef CUT_HF
 830           if(cb == 21) {
 831             fprintf(stderr,"c");
 832             v = 0.0;
 833           }
 834           else
 835 #endif
 836             v = gr_info->pow2gain[((*scf++) + (*pretab++)) << shift];
 837
 838         }
 839         {
 840           register short *val = h->table;
 841           REFRESH_MASK;
 842           while((y=*val++)<0) {
 843             if (mask < 0)
 844               val -= y;
 845             num--;
 846             mask <<= 1;
 847           }
 848           x = y >> 4;
 849           y &= 0xf;
 850         }
 851
 852         if (x == 15 && h->linbits) {
 853           max = cb;
 854           REFRESH_MASK;
 855           x += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
 856           num -= h->linbits+1;
 857           mask <<= h->linbits;
 858           if(mask < 0)
 859             *xrpnt++ = REAL_MUL(-ispow[x], v);
 860           else
 861             *xrpnt++ = REAL_MUL(ispow[x], v);
 862           mask <<= 1;
 863         }
 864         else if(x) {
 865           max = cb;
 866           if(mask < 0)
 867             *xrpnt++ = REAL_MUL(-ispow[x], v);
 868           else
 869             *xrpnt++ = REAL_MUL(ispow[x], v);
 870           num--;
 871           mask <<= 1;
 872         }
 873         else
 874           *xrpnt++ = 0.0;
 875
 876         if (y == 15 && h->linbits) {
 877           max = cb;
 878           REFRESH_MASK;
 879           y += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
 880           num -= h->linbits+1;
 881           mask <<= h->linbits;
 882           if(mask < 0)
 883             *xrpnt++ = REAL_MUL(-ispow[y], v);
 884           else
 885             *xrpnt++ = REAL_MUL(ispow[y], v);
 886           mask <<= 1;
 887         }
 888         else if(y) {
 889           max = cb;
 890           if(mask < 0)
 891             *xrpnt++ = REAL_MUL(-ispow[y], v);
 892           else
 893             *xrpnt++ = REAL_MUL(ispow[y], v);
 894           num--;
 895           mask <<= 1;
 896         }
 897         else
 898           *xrpnt++ = 0.0;
 899       }
 900     }
 901
 902     /*
 903      * short (count1table) values
 904      */
 905     for(;l3 && (part2remain+num > 0);l3--) {
 906       struct newhuff *h = htc+gr_info->count1table_select;
 907       register short *val = h->table,a;
 908
 909       REFRESH_MASK;
 910       while((a=*val++)<0) {
 911         if (mask < 0)
 912           val -= a;
 913         num--;
 914         mask <<= 1;
 915       }
 916       if(part2remain+num <= 0) {
 917         num -= part2remain+num;
 918         break;
 919       }
 920
 921       for(i=0;i<4;i++) {
 922         if(!(i & 1)) {
 923           if(!mc) {
 924             mc = *m++;
 925             cb = *m++;
 926 #ifdef CUT_HF
 927             if(cb == 21) {
 928               fprintf(stderr,"c");
 929               v = 0.0;
 930             }
 931             else
 932 #endif
 933               v = gr_info->pow2gain[((*scf++) + (*pretab++)) << shift];
 934           }
 935           mc--;
 936         }
 937         if ( (a & (0x8>>i)) ) {
 938           max = cb;
 939           if(part2remain+num <= 0) {
 940             break;
 941           }
 942           if(mask < 0)
 943             *xrpnt++ = -v;
 944           else
 945             *xrpnt++ = v;
 946           num--;
 947           mask <<= 1;
 948         }
 949         else
 950           *xrpnt++ = 0.0;
 951       }
 952     }
 953
 954     gr_info->maxbandl = max+1;
 955     gr_info->maxb = longLimit[sfreq][gr_info->maxbandl];
 956   }
 957
 958   part2remain += num;
 959 //  backbits(num);
 960   bitindex -= num; wordpointer += (bitindex>>3); bitindex &= 0x7;
 961   num = 0;
 962
 963   while(xrpnt < &xr[SBLIMIT][0])
 964     *xrpnt++ = 0.0;
 965
 966   while( part2remain > 16 ) {
 967     getbits(16); /* Dismiss stuffing Bits */
 968     part2remain -= 16;
 969   }
 970   if(part2remain > 0)
 971     getbits(part2remain);
 972   else if(part2remain < 0) {
 973       fprintf(stderr,"mpg123: Can't rewind stream by %d bits!\n",-part2remain);
 974     return 1; /* -> error */
 975   }
 976   return 0;
 977 }
 978
 979
 980
 981
 982 /*
 983  * III_stereo: calculate real channel values for Joint-I-Stereo-mode
 984  */
 985 static void III_i_stereo(real xr_buf[2][SBLIMIT][SSLIMIT],int *scalefac,
 986    struct gr_info_s *gr_info,int sfreq,int ms_stereo,int lsf)
 987 {
 988       real (*xr)[SBLIMIT*SSLIMIT] = (real (*)[SBLIMIT*SSLIMIT] ) xr_buf;
 989       const struct bandInfoStruct *bi = &bandInfo[sfreq];
 990
 991       const real *tab1,*tab2;
 992
 993       int tab;
 994       static const real *tabs[3][2][2] = {
 995          { { tan1_1,tan2_1 }     , { tan1_2,tan2_2 } },
 996          { { pow1_1[0],pow2_1[0] } , { pow1_2[0],pow2_2[0] } } ,
 997          { { pow1_1[1],pow2_1[1] } , { pow1_2[1],pow2_2[1] } }
 998       };
 999
1000       tab = lsf + (gr_info->scalefac_compress & lsf);
1001       tab1 = tabs[tab][ms_stereo][0];
1002       tab2 = tabs[tab][ms_stereo][1];
1003 #if 0
1004       if(lsf) {
1005         int p = gr_info->scalefac_compress & 0x1;
1006         if(ms_stereo) {
1007           tab1 = pow1_2[p]; tab2 = pow2_2[p];
1008         }
1009         else {
1010           tab1 = pow1_1[p]; tab2 = pow2_1[p];
1011         }
1012       }
1013       else {
1014         if(ms_stereo) {
1015           tab1 = tan1_2; tab2 = tan2_2;
1016         }
1017         else {
1018           tab1 = tan1_1; tab2 = tan2_1;
1019         }
1020       }
1021 #endif
1022
1023 //      printf("III_i_st: tab1=%p tab2=%p tab=%d ms=%d  \n", tab1, tab2, tab, ms_stereo);
1024
1025       if (gr_info->block_type == 2) {
1026          int lwin,do_l = 0;
1027          if( gr_info->mixed_block_flag )
1028            do_l = 1;
1029
1030          for (lwin=0;lwin<3;lwin++) { /* process each window */
1031              /* get first band with zero values */
1032            int is_p,sb,idx,sfb = gr_info->maxband[lwin];  /* sfb is minimal 3 for mixed mode */
1033            if(sfb > 3)
1034              do_l = 0;
1035
1036            for(;sfb<12;sfb++) {
1037              is_p = scalefac[sfb*3+lwin-gr_info->mixed_block_flag]; /* scale: 0-15 */
1038              if(is_p != 7) {
1039                real t1,t2;
1040                sb  = bi->shortDiff[sfb];
1041                idx = bi->shortIdx[sfb] + lwin;
1042                t1  = tab1[is_p]; t2 = tab2[is_p];
1043                for (; sb > 0; sb--,idx+=3) {
1044                  real v = xr[0][idx];
1045                  xr[0][idx] = REAL_MUL(v, t1);
1046                  xr[1][idx] = REAL_MUL(v, t2);
1047                }
1048              }
1049            }
1050
1051 #if 1
1052 /* in the original: copy 10 to 11 , here: copy 11 to 12
1053 maybe still wrong??? (copy 12 to 13?) */
1054            is_p = scalefac[11*3+lwin-gr_info->mixed_block_flag]; /* scale: 0-15 */
1055            sb   = bi->shortDiff[12];
1056            idx  = bi->shortIdx[12] + lwin;
1057 #else
1058            is_p = scalefac[10*3+lwin-gr_info->mixed_block_flag]; /* scale: 0-15 */
1059            sb   = bi->shortDiff[11];
1060            idx  = bi->shortIdx[11] + lwin;
1061 #endif
1062            if(is_p != 7) {
1063              real t1,t2;
1064              t1 = tab1[is_p]; t2 = tab2[is_p];
1065              for ( ; sb > 0; sb--,idx+=3 ) {
1066                real v = xr[0][idx];
1067                xr[0][idx] = REAL_MUL(v, t1);
1068                xr[1][idx] = REAL_MUL(v, t2);
1069              }
1070            }
1071          } /* end for(lwin; .. ; . ) */
1072
1073 /* also check l-part, if ALL bands in the three windows are 'empty'
1074  * and mode = mixed_mode
1075  */
1076          if (do_l) {
1077            int sfb = gr_info->maxbandl;
1078            int idx = bi->longIdx[sfb];
1079
1080            for ( ; sfb<8; sfb++ ) {
1081              int sb = bi->longDiff[sfb];
1082              int is_p = scalefac[sfb]; /* scale: 0-15 */
1083              if(is_p != 7) {
1084                real t1,t2;
1085                t1 = tab1[is_p]; t2 = tab2[is_p];
1086                for ( ; sb > 0; sb--,idx++) {
1087                  real v = xr[0][idx];
1088                  xr[0][idx] = REAL_MUL(v, t1);
1089                  xr[1][idx] = REAL_MUL(v, t2);
1090                }
1091              }
1092              else
1093                idx += sb;
1094            }
1095          }
1096       }
1097       else { /* ((gr_info->block_type != 2)) */
1098        int sfb = gr_info->maxbandl;
1099        int is_p,idx = bi->longIdx[sfb];
1100
1101 /* hmm ... maybe the maxbandl stuff for i-stereo is buggy? */
1102        if(sfb <= 21) {
1103         for ( ; sfb<21; sfb++) {
1104           int sb = bi->longDiff[sfb];
1105           is_p = scalefac[sfb]; /* scale: 0-15 */
1106           if(is_p != 7) {
1107             real t1,t2;
1108             t1 = tab1[is_p]; t2 = tab2[is_p];
1109             for ( ; sb > 0; sb--,idx++) {
1110                real v = xr[0][idx];
1111                xr[0][idx] = REAL_MUL(v, t1);
1112                xr[1][idx] = REAL_MUL(v, t2);
1113             }
1114           }
1115           else
1116             idx += sb;
1117         }
1118
1119         is_p = scalefac[20];
1120         if(is_p != 7) {  /* copy l-band 20 to l-band 21 */
1121           int sb;
1122           real t1 = tab1[is_p],t2 = tab2[is_p];
1123
1124           for ( sb = bi->longDiff[21]; sb > 0; sb--,idx++ ) {
1125             real v = xr[0][idx];
1126             xr[0][idx] = REAL_MUL(v, t1);
1127             xr[1][idx] = REAL_MUL(v, t2);
1128           }
1129         }
1130        }        /* end: if(sfb <= 21) */
1131       } /* ... */
1132 }
1133
1134 static void III_antialias(real xr[SBLIMIT][SSLIMIT],struct gr_info_s *gr_info) {
1135    int sblim;
1136
1137    if(gr_info->block_type == 2) {
1138       if(!gr_info->mixed_block_flag)
1139         return;
1140       sblim = 1;
1141    }
1142    else {
1143      sblim = gr_info->maxb-1;
1144    }
1145
1146    /* 31 alias-reduction operations between each pair of sub-bands */
1147    /* with 8 butterflies between each pair                         */
1148
1149    {
1150      int sb;
1151      real *xr1=(real *) xr[1];
1152
1153      for(sb=sblim;sb;sb--,xr1+=10) {
1154        int ss;
1155        real *cs=aa_cs,*ca=aa_ca;
1156        real *xr2 = xr1;
1157
1158        for(ss=7;ss>=0;ss--) {    /* upper and lower butterfly inputs */
1159          register real bu = *--xr2,bd = *xr1;
1160          *xr2   = (bu * (*cs)   ) - (bd * (*ca)   );
1161          *xr1++ = (bd * (*cs++) ) + (bu * (*ca++) );
1162        }
1163      }
1164
1165   }
1166 }
1167
1168 #include "dct64.c"
1169 #include "dct36.c"
1170 #include "dct12.c"
1171
1172 #include "decod386.c"
1173
1174 /*
1175  * III_hybrid
1176  */
1177
1178 static dct36_func_t dct36_func;
1179
1180 static void III_hybrid(real fsIn[SBLIMIT][SSLIMIT],real tsOut[SSLIMIT][SBLIMIT],
1181    int ch,struct gr_info_s *gr_info)
1182 {
1183    real *tspnt = (real *) tsOut;
1184    static real block[2][2][SBLIMIT*SSLIMIT] = { { { 0, } } };
1185    static int blc[2]={0,0};
1186    real *rawout1,*rawout2;
1187    int bt;
1188    int sb = 0;
1189
1190    {
1191      int b = blc[ch];
1192      rawout1=block[b][ch];
1193      b=-b+1;
1194      rawout2=block[b][ch];
1195      blc[ch] = b;
1196    }
1197
1198    if(gr_info->mixed_block_flag) {
1199      sb = 2;
1200      (*dct36_func)(fsIn[0],rawout1,rawout2,win[0],tspnt);
1201      (*dct36_func)(fsIn[1],rawout1+18,rawout2+18,win1[0],tspnt+1);
1202      rawout1 += 36; rawout2 += 36; tspnt += 2;
1203    }
1204
1205    bt = gr_info->block_type;
1206    if(bt == 2) {
1207      for (; sb<gr_info->maxb; sb+=2,tspnt+=2,rawout1+=36,rawout2+=36) {
1208        dct12(fsIn[sb],rawout1,rawout2,win[2],tspnt);
1209        dct12(fsIn[sb+1],rawout1+18,rawout2+18,win1[2],tspnt+1);
1210      }
1211    }
1212    else {
1213      for (; sb<gr_info->maxb; sb+=2,tspnt+=2,rawout1+=36,rawout2+=36) {
1214        (*dct36_func)(fsIn[sb],rawout1,rawout2,win[bt],tspnt);
1215        (*dct36_func)(fsIn[sb+1],rawout1+18,rawout2+18,win1[bt],tspnt+1);
1216      }
1217    }
1218
1219    for(;sb<SBLIMIT;sb++,tspnt++) {
1220      int i;
1221      for(i=0;i<SSLIMIT;i++) {
1222        tspnt[i*SBLIMIT] = *rawout1++;
1223        *rawout2++ = 0.0;
1224      }
1225    }
1226 }
1227
1228 /*
1229  * main layer3 handler
1230  */
1231 /* int do_layer3(struct frame *fr,int outmode,struct audio_info_struct *ai) */
1232 static int do_layer3(struct frame *fr,int single){
1233   int gr, ch, ss,clip=0;
1234   int scalefacs[2][39]; /* max 39 for short[13][3] mode, mixed: 38, long: 22 */
1235   struct III_sideinfo sideinfo;
1236   int stereo = fr->stereo;
1237   int ms_stereo,i_stereo;
1238   int sfreq = fr->sampling_frequency;
1239   int stereo1,granules;
1240
1241 //  if (fr->error_protection) getbits(16); /* skip crc */
1242
1243   if(stereo == 1) { /* stream is mono */
1244     stereo1 = 1;
1245     single = 0;
1246   } else
1247   if(single >= 0) /* stream is stereo, but force to mono */
1248     stereo1 = 1;
1249   else
1250     stereo1 = 2;
1251
1252   if(fr->mode == MPG_MD_JOINT_STEREO) {
1253     ms_stereo = (fr->mode_ext & 0x2)>>1;
1254     i_stereo  = fr->mode_ext & 0x1;
1255   } else
1256     ms_stereo = i_stereo = 0;
1257
1258   if(!III_get_side_info(&sideinfo,stereo,ms_stereo,sfreq,single,fr->lsf))
1259     return -1;
1260
1261   set_pointer(sideinfo.main_data_begin);
1262
1263   granules = (fr->lsf) ? 1 : 2;
1264   for (gr=0;gr<granules;gr++){
1265     DECLARE_ALIGNED(16, real, hybridIn[2][SBLIMIT][SSLIMIT]);
1266     DECLARE_ALIGNED(16, real, hybridOut[2][SSLIMIT][SBLIMIT]);
1267
1268     { struct gr_info_s *gr_info = &(sideinfo.ch[0].gr[gr]);
1269       int part2bits;
1270       if(fr->lsf)
1271         part2bits = III_get_scale_factors_2(scalefacs[0],gr_info,0);
1272       else
1273         part2bits = III_get_scale_factors_1(scalefacs[0],gr_info);
1274       if(III_dequantize_sample(hybridIn[0], scalefacs[0],gr_info,sfreq,part2bits))
1275         return clip;
1276     }
1277
1278     if(stereo == 2) {
1279       struct gr_info_s *gr_info = &(sideinfo.ch[1].gr[gr]);
1280
1281       int part2bits;
1282       if(fr->lsf)
1283         part2bits = III_get_scale_factors_2(scalefacs[1],gr_info,i_stereo);
1284       else
1285         part2bits = III_get_scale_factors_1(scalefacs[1],gr_info);
1286
1287       if(III_dequantize_sample(hybridIn[1],scalefacs[1],gr_info,sfreq,part2bits))
1288           return clip;
1289
1290       if(ms_stereo) {
1291         int i;
1292         int maxb = sideinfo.ch[0].gr[gr].maxb;
1293         if(sideinfo.ch[1].gr[gr].maxb > maxb)
1294             maxb = sideinfo.ch[1].gr[gr].maxb;
1295         for(i=0;i<SSLIMIT*maxb;i++) {
1296           real tmp0 = ((real *)hybridIn[0])[i];
1297           real tmp1 = ((real *)hybridIn[1])[i];
1298           ((real *)hybridIn[0])[i] = tmp0 + tmp1;
1299           ((real *)hybridIn[1])[i] = tmp0 - tmp1;
1300         }
1301       }
1302
1303       if(i_stereo)
1304         III_i_stereo(hybridIn,scalefacs[1],gr_info,sfreq,ms_stereo,fr->lsf);
1305
1306       if(ms_stereo || i_stereo || (single == 3) ) {
1307         if(gr_info->maxb > sideinfo.ch[0].gr[gr].maxb)
1308           sideinfo.ch[0].gr[gr].maxb = gr_info->maxb;
1309         else
1310           gr_info->maxb = sideinfo.ch[0].gr[gr].maxb;
1311       }
1312
1313       switch(single) {
1314         case 3: {
1315           register int i;
1316           register real *in0 = (real *) hybridIn[0],*in1 = (real *) hybridIn[1];
1317           for(i=0;i<SSLIMIT*gr_info->maxb;i++,in0++)
1318             *in0 = (*in0 + *in1++); /* *0.5 done by pow-scale */
1319           break; }
1320         case 1: {
1321           register int i;
1322           register real *in0 = (real *) hybridIn[0],*in1 = (real *) hybridIn[1];
1323           for(i=0;i<SSLIMIT*gr_info->maxb;i++)
1324             *in0++ = *in1++;
1325           break; }
1326       }
1327
1328     }  // if(stereo == 2)
1329
1330     for(ch=0;ch<stereo1;ch++) {
1331       struct gr_info_s *gr_info = &(sideinfo.ch[ch].gr[gr]);
1332                   III_antialias(hybridIn[ch],gr_info);
1333                   III_hybrid(hybridIn[ch], hybridOut[ch], ch,gr_info);
1334     }
1335
1336     for(ss=0;ss<SSLIMIT;ss++) {
1337       if(single >= 0) {
1338                     clip += (fr->synth_mono)(hybridOut[0][ss],pcm_sample,&pcm_point);
1339                 } else {
1340                   int p1 = pcm_point;
1341                     clip += (fr->synth)(hybridOut[0][ss],0,pcm_sample,&p1);
1342                     clip += (fr->synth)(hybridOut[1][ss],1,pcm_sample,&pcm_point);
1343       }
1344     }
1345
1346   }
1347
1348   return clip;
1349 }