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Sourcecode: kdemultimedia version File versions

layer3.c

/* 
 * Mpeg Layer-3 audio decoder 
 * --------------------------
 * copyright (c) 1995-1999 by Michael Hipp.
 * All rights reserved. See also 'README'
 *
 * Optimize-TODO: put short bands into the band-field without the stride 
 *                of 3 reals
 * Length-optimze: unify long and short band code where it is possible
 */ 

#if 0
#define L3_DEBUG 1
#endif

#if 0
#define CUT_HF
#endif

#include <stdlib.h>
#include "mpg123.h"
#include "huffman.h"

#include "common.h"

#include "getbits.h"

static real ispow[8207];
static real aa_ca[8],aa_cs[8];
static real COS1[12][6];
static real win[4][36];
static real win1[4][36];
static real gainpow2[256+118+4];

/* non static for external 3dnow functions */
real   COS9[9];
static real COS6_1,COS6_2;
real   tfcos36[9];

static real tfcos12[3];
#define NEW_DCT9
#ifdef NEW_DCT9
static real cos9[3],cos18[3];
#endif

struct bandInfoStruct {
  int longIdx[23];
  int longDiff[22];
  int shortIdx[14];
  int shortDiff[13];
};

int longLimit[9][23];
int shortLimit[9][14];

struct bandInfoStruct bandInfo[9] = { 

/* MPEG 1.0 */
 { {0,4,8,12,16,20,24,30,36,44,52,62,74, 90,110,134,162,196,238,288,342,418,576},
   {4,4,4,4,4,4,6,6,8, 8,10,12,16,20,24,28,34,42,50,54, 76,158},
   {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},
   {4,4,4,4,6,8,10,12,14,18,22,30,56} } ,

 { {0,4,8,12,16,20,24,30,36,42,50,60,72, 88,106,128,156,190,230,276,330,384,576},
   {4,4,4,4,4,4,6,6,6, 8,10,12,16,18,22,28,34,40,46,54, 54,192},
   {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},
   {4,4,4,4,6,6,10,12,14,16,20,26,66} } ,

 { {0,4,8,12,16,20,24,30,36,44,54,66,82,102,126,156,194,240,296,364,448,550,576} ,
   {4,4,4,4,4,4,6,6,8,10,12,16,20,24,30,38,46,56,68,84,102, 26} ,
   {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} ,
   {4,4,4,4,6,8,12,16,20,26,34,42,12} }  ,

/* MPEG 2.0 */
 { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
   {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54 } ,
   {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} ,
   {4,4,4,6,6,8,10,14,18,26,32,42,18 } } ,
/*
 { {0,6,12,18,24,30,36,44,54,66,80,96,114,136,162,194,232,278,330,394,464,540,576},
   {6,6,6,6,6,6,8,10,12,14,16,18,22,26,32,38,46,52,64,70,76,36 } ,
*/
/* changed 19th value fropm 330 to 332 */
 { {0,6,12,18,24,30,36,44,54,66,80,96,114,136,162,194,232,278,332,394,464,540,576},
   {6,6,6,6,6,6,8,10,12,14,16,18,22,26,32,38,46,54,62,70,76,36 } ,
   {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} ,
   {4,4,4,6,8,10,12,14,18,24,32,44,12 } } ,

 { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576},
   {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54 },
   {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},
   {4,4,4,6,8,10,12,14,18,24,30,40,18 } } ,
/* MPEG 2.5 */
 { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576} ,
   {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54},
   {0,12,24,36,54,78,108,144,186,240,312,402,522,576},
   {4,4,4,6,8,10,12,14,18,24,30,40,18} },
 { {0,6,12,18,24,30,36,44,54,66,80,96,116,140,168,200,238,284,336,396,464,522,576} ,
   {6,6,6,6,6,6,8,10,12,14,16,20,24,28,32,38,46,52,60,68,58,54},
   {0,12,24,36,54,78,108,144,186,240,312,402,522,576},
   {4,4,4,6,8,10,12,14,18,24,30,40,18} },
 { {0,12,24,36,48,60,72,88,108,132,160,192,232,280,336,400,476,566,568,570,572,574,576},
   {12,12,12,12,12,12,16,20,24,28,32,40,48,56,64,76,90,2,2,2,2,2},
   {0, 24, 48, 72,108,156,216,288,372,480,486,492,498,576},
   {8,8,8,12,16,20,24,28,36,2,2,2,26} } ,
};

static int mapbuf0[9][152];
static int mapbuf1[9][156];
static int mapbuf2[9][44];
static int *map[9][3];
static int *mapend[9][3];

static unsigned int n_slen2[512]; /* MPEG 2.0 slen for 'normal' mode */
static unsigned int i_slen2[256]; /* MPEG 2.0 slen for intensity stereo */

static real tan1_1[16],tan2_1[16],tan1_2[16],tan2_2[16];
static real pow1_1[2][16],pow2_1[2][16],pow1_2[2][16],pow2_2[2][16];

/* 
 * init tables for layer-3 
 */
void init_layer3(int down_sample_sblimit)
{
  int i,j,k,l;

#ifdef REAL_IS_FIXED
  double tmparray[8207];
  double twotothequarter = pow((double)2.0, (double)0.25);
  double current = pow((double)2.0, (double)(0.25 * 47));
#endif

  for(i=-256;i<118+4;i++) {
#ifdef REAL_IS_FIXED
  /* Possibly a few too many multiplies - single bit errors will
   * propagate. It may change the gradient of the (log) power curve
   * slighty */
   current = current / twotothequarter;
   gainpow2[i+256] = DOUBLE_TO_REAL(current);
#else
# ifdef USE_MMX
    if(!param.down_sample)
      gainpow2[i+256] = 16384.0 * pow((double)2.0,-0.25 * (double) (i+210) );
    else
# endif
    gainpow2[i+256] = DOUBLE_TO_REAL(pow((double)2.0,-0.25 * (double) (i+210) ));
#endif
  }

#ifdef REAL_IS_FIXED
  for(i=0;i<8207;i++)
     tmparray[i] = 0.0;
  tmparray[1] = 1.0;
  for(i=2;i<8207;i++) {
     if(!tmparray[i]) {
      tmparray[i] = pow((double)i,(double)(4.0/3.0));
      for(j = 2; (j <= i) && ((i * j) < 8207); j++) {
         /* Degradation due to lots of multiplies: A double has
          * 52 bits of mantissa. A long has 32 bits (on the IPaq).
          * Hence we can create 20 bits of error without fussing.
          * Assuming that a 1 bit error multiplies to 2 bits, then 4,
          * then 8, and noting that 2^13 is 8196 (we go up to 8207),
          * we may have a problem. Resolve this by limiting to 4
          * multiplies before recalculating. */
         for(k = i, l = 0; (k * j) <= 8207 && (l < 4); k *= j, l++) {
            tmparray[k * j] = tmparray[k] * tmparray[j];
         }
      }
     }
     ispow[i] = DOUBLE_TO_REAL(tmparray[i]);
  }
#else
  for(i=0;i<8207;i++)
    ispow[i] = DOUBLE_TO_REAL(pow((double)i,(double)4.0/3.0));
#endif

  for (i=0;i<8;i++) {
    static double Ci[8]={-0.6,-0.535,-0.33,-0.185,-0.095,-0.041,-0.0142,-0.0037};
    double sq=sqrt(1.0+Ci[i]*Ci[i]);
    aa_cs[i] = DOUBLE_TO_REAL(1.0/sq);
    aa_ca[i] = DOUBLE_TO_REAL(Ci[i]/sq);
  }

  for(i=0;i<18;i++) {
    win[0][i]    = win[1][i]    = 
      DOUBLE_TO_REAL(0.5 * sin( M_PI / 72.0 * (double) (2*(i+0) +1) ) / cos ( M_PI * (double) (2*(i+0) +19) / 72.0 ));
    win[0][i+18] = win[3][i+18] = 
      DOUBLE_TO_REAL(0.5 * sin( M_PI / 72.0 * (double) (2*(i+18)+1) ) / cos ( M_PI * (double) (2*(i+18)+19) / 72.0 ));
  }
  for(i=0;i<6;i++) {
    win[1][i+18] = DOUBLE_TO_REAL(0.5 / cos ( M_PI * (double) (2*(i+18)+19) / 72.0 ));
    win[3][i+12] = DOUBLE_TO_REAL(0.5 / cos ( M_PI * (double) (2*(i+12)+19) / 72.0 ));
    win[1][i+24] = DOUBLE_TO_REAL(0.5 * sin( M_PI / 24.0 * (double) (2*i+13) ) / cos ( M_PI * (double) (2*(i+24)+19) / 72.0 ));
    win[1][i+30] = win[3][i] = DOUBLE_TO_REAL(0.0);
    win[3][i+6 ] = DOUBLE_TO_REAL(0.5 * sin( M_PI / 24.0 * (double) (2*i+1) )  / cos ( M_PI * (double) (2*(i+6 )+19) / 72.0 ));
  }

  for(i=0;i<9;i++)
    COS9[i] = DOUBLE_TO_REAL(cos( M_PI / 18.0 * (double) i));

  for(i=0;i<9;i++)
    tfcos36[i] = DOUBLE_TO_REAL(0.5 / cos ( M_PI * (double) (i*2+1) / 36.0 ));
  for(i=0;i<3;i++)
    tfcos12[i] = DOUBLE_TO_REAL(0.5 / cos ( M_PI * (double) (i*2+1) / 12.0 ));

  COS6_1 = DOUBLE_TO_REAL(cos( M_PI / 6.0 * (double) 1));
  COS6_2 = DOUBLE_TO_REAL(cos( M_PI / 6.0 * (double) 2));

#ifdef NEW_DCT9
  cos9[0]  = DOUBLE_TO_REAL(cos(1.0*M_PI/9.0));
  cos9[1]  = DOUBLE_TO_REAL(cos(5.0*M_PI/9.0));
  cos9[2]  = DOUBLE_TO_REAL(cos(7.0*M_PI/9.0));
  cos18[0] = DOUBLE_TO_REAL(cos(1.0*M_PI/18.0));
  cos18[1] = DOUBLE_TO_REAL(cos(11.0*M_PI/18.0));
  cos18[2] = DOUBLE_TO_REAL(cos(13.0*M_PI/18.0));
#endif

  for(i=0;i<12;i++) {
    win[2][i]  = DOUBLE_TO_REAL(0.5 * sin( M_PI / 24.0 * (double) (2*i+1) ) / cos ( M_PI * (double) (2*i+7) / 24.0 ));
    for(j=0;j<6;j++)
      COS1[i][j] = DOUBLE_TO_REAL(cos( M_PI / 24.0 * (double) ((2*i+7)*(2*j+1)) ));
  }

  for(j=0;j<4;j++) {
    static int len[4] = { 36,36,12,36 };
    for(i=0;i<len[j];i+=2)
      win1[j][i] = + win[j][i];
    for(i=1;i<len[j];i+=2)
      win1[j][i] = - win[j][i];
  }

  for(i=0;i<16;i++) {
    double t = tan( (double) i * M_PI / 12.0 );
    tan1_1[i] = DOUBLE_TO_REAL(t / (1.0+t));
    tan2_1[i] = DOUBLE_TO_REAL(1.0 / (1.0 + t));
    tan1_2[i] = DOUBLE_TO_REAL(M_SQRT2 * t / (1.0+t));
    tan2_2[i] = DOUBLE_TO_REAL(M_SQRT2 / (1.0 + t));

    for(j=0;j<2;j++) {
      double base = pow(2.0,-0.25*(j+1.0));
      double p1=1.0,p2=1.0;
      if(i > 0) {
        if( i & 1 )
          p1 = pow(base,(i+1.0)*0.5);
        else
          p2 = pow(base,i*0.5);
      }
      pow1_1[j][i] = DOUBLE_TO_REAL(p1);
      pow2_1[j][i] = DOUBLE_TO_REAL(p2);
      pow1_2[j][i] = DOUBLE_TO_REAL(M_SQRT2 * p1);
      pow2_2[j][i] = DOUBLE_TO_REAL(M_SQRT2 * p2);
    }
  }

  for(j=0;j<9;j++) {
   struct bandInfoStruct *bi = &bandInfo[j];
   int *mp;
   int cb,lwin;
   int *bdf;

   mp = map[j][0] = mapbuf0[j];
   bdf = bi->longDiff;
   for(i=0,cb = 0; cb < 8 ; cb++,i+=*bdf++) {
     *mp++ = (*bdf) >> 1;
     *mp++ = i;
     *mp++ = 3;
     *mp++ = cb;
   }
   bdf = bi->shortDiff+3;
   for(cb=3;cb<13;cb++) {
     int l = (*bdf++) >> 1;
     for(lwin=0;lwin<3;lwin++) {
       *mp++ = l;
       *mp++ = i + lwin;
       *mp++ = lwin;
       *mp++ = cb;
     }
     i += 6*l;
   }
   mapend[j][0] = mp;

   mp = map[j][1] = mapbuf1[j];
   bdf = bi->shortDiff+0;
   for(i=0,cb=0;cb<13;cb++) {
     int l = (*bdf++) >> 1;
     for(lwin=0;lwin<3;lwin++) {
       *mp++ = l;
       *mp++ = i + lwin;
       *mp++ = lwin;
       *mp++ = cb;
     }
     i += 6*l;
   }
   mapend[j][1] = mp;

   mp = map[j][2] = mapbuf2[j];
   bdf = bi->longDiff;
   for(cb = 0; cb < 22 ; cb++) {
     *mp++ = (*bdf++) >> 1;
     *mp++ = cb;
   }
   mapend[j][2] = mp;

  }

  for(j=0;j<9;j++) {
    for(i=0;i<23;i++) {
      longLimit[j][i] = (bandInfo[j].longIdx[i] - 1 + 8) / 18 + 1;
      if(longLimit[j][i] > (down_sample_sblimit) )
        longLimit[j][i] = down_sample_sblimit;
    }
    for(i=0;i<14;i++) {
      shortLimit[j][i] = (bandInfo[j].shortIdx[i] - 1) / 18 + 1;
      if(shortLimit[j][i] > (down_sample_sblimit) )
        shortLimit[j][i] = down_sample_sblimit;
    }
  }

  for(i=0;i<5;i++) {
    for(j=0;j<6;j++) {
      for(k=0;k<6;k++) {
        int n = k + j * 6 + i * 36;
        i_slen2[n] = i|(j<<3)|(k<<6)|(3<<12);
      }
    }
  }
  for(i=0;i<4;i++) {
    for(j=0;j<4;j++) {
      for(k=0;k<4;k++) {
        int n = k + j * 4 + i * 16;
        i_slen2[n+180] = i|(j<<3)|(k<<6)|(4<<12);
      }
    }
  }
  for(i=0;i<4;i++) {
    for(j=0;j<3;j++) {
      int n = j + i * 3;
      i_slen2[n+244] = i|(j<<3) | (5<<12);
      n_slen2[n+500] = i|(j<<3) | (2<<12) | (1<<15);
    }
  }

  for(i=0;i<5;i++) {
    for(j=0;j<5;j++) {
      for(k=0;k<4;k++) {
        for(l=0;l<4;l++) {
          int n = l + k * 4 + j * 16 + i * 80;
          n_slen2[n] = i|(j<<3)|(k<<6)|(l<<9)|(0<<12);
        }
      }
    }
  }
  for(i=0;i<5;i++) {
    for(j=0;j<5;j++) {
      for(k=0;k<4;k++) {
        int n = k + j * 4 + i * 20;
        n_slen2[n+400] = i|(j<<3)|(k<<6)|(1<<12);
      }
    }
  }
}

/*
 * read additional side information (for MPEG 1 and MPEG 2)
 */
static int III_get_side_info(struct III_sideinfo *si,int stereo,
 int ms_stereo,long sfreq,int single,int lsf)
{
   int ch, gr;
   int powdiff = (single == 3) ? 4 : 0;

   static const int tabs[2][5] = { { 2,9,5,3,4 } , { 1,8,1,2,9 } };
   const int *tab = tabs[lsf];
   
   si->main_data_begin = getbits(&bsi,tab[1]);
   if (stereo == 1)
     si->private_bits = getbits_fast(&bsi,tab[2]);
   else 
     si->private_bits = getbits_fast(&bsi,tab[3]);

   if(!lsf) {
     for (ch=0; ch<stereo; ch++) {
         si->ch[ch].gr[0].scfsi = -1;
         si->ch[ch].gr[1].scfsi = getbits_fast(&bsi,4);
     }
   }

   for (gr=0; gr<tab[0]; gr++) {
     for (ch=0; ch<stereo; ch++) {
       register struct gr_info_s *gr_info = &(si->ch[ch].gr[gr]);

       gr_info->part2_3_length = getbits(&bsi,12);
       gr_info->big_values = getbits(&bsi,9);
       if(gr_info->big_values > 288) {
          if(param.verbose)
            fprintf(stderr,"big_values too large!\n");
          gr_info->big_values = 288;
       }
       gr_info->pow2gain = gainpow2+256 - getbits_fast(&bsi,8) + powdiff;
       if(ms_stereo)
         gr_info->pow2gain += 2;
       gr_info->scalefac_compress = getbits(&bsi,tab[4]);

       if(get1bit(&bsi)) { /* window switch flag  */
         int i;
#ifdef L3_DEBUG
if(2*gr_info->big_values > bandInfo[sfreq].shortIdx[12])
  fprintf(stderr,"L3: BigValues too large, doesn't make sense %d %d\n",2*gr_info->big_values,bandInfo[sfreq].shortIdx[12]);
#endif

         gr_info->block_type       = getbits_fast(&bsi,2);
         gr_info->mixed_block_flag = get1bit(&bsi);
         gr_info->table_select[0]  = getbits_fast(&bsi,5);
         gr_info->table_select[1]  = getbits_fast(&bsi,5);
         /*
          * table_select[2] not needed, because there is no region2,
          * but to satisfy some verifications tools we set it either.
          */
         gr_info->table_select[2] = 0;
         for(i=0;i<3;i++)
           gr_info->full_gain[i] = gr_info->pow2gain + (getbits_fast(&bsi,3)<<3);

         if(gr_info->block_type == 0) {
           if(param.verbose) 
             fprintf(stderr,"Blocktype == 0 and window-switching == 1 not allowed.\n");
           return 0;
         }
      
         /* region_count/start parameters are implicit in this case. */       
         if(!lsf || gr_info->block_type == 2)
           gr_info->region1start = 36>>1;
         else {
/* check this again for 2.5 and sfreq=8 */
           if(sfreq == 8)
             gr_info->region1start = 108>>1;
           else
             gr_info->region1start = 54>>1;
         }
         gr_info->region2start = 576>>1;
       }
       else {
         int i,r0c,r1c;
#ifdef L3_DEBUG
if(2*gr_info->big_values > bandInfo[sfreq].longIdx[21])
  fprintf(stderr,"L3: BigValues too large, doesn't make sense %d %d\n",2*gr_info->big_values,bandInfo[sfreq].longIdx[21]);
#endif
         for (i=0; i<3; i++)
           gr_info->table_select[i] = getbits_fast(&bsi,5);
         r0c = getbits_fast(&bsi,4);
         r1c = getbits_fast(&bsi,3);
         gr_info->region1start = bandInfo[sfreq].longIdx[r0c+1] >> 1 ;
         if(r0c + r1c + 2 > 22)
           gr_info->region2start = 576>>1;
         else
           gr_info->region2start = bandInfo[sfreq].longIdx[r0c+1+r1c+1] >> 1;
         gr_info->block_type = 0;
         gr_info->mixed_block_flag = 0;
       }
       if(!lsf)
         gr_info->preflag = get1bit(&bsi);
       gr_info->scalefac_scale = get1bit(&bsi);
       gr_info->count1table_select = get1bit(&bsi);
     }
   }

   return !0;
}

/*
 * read scalefactors
 */
static int III_get_scale_factors_1(int *scf,struct gr_info_s *gr_info)
{
   static const unsigned char slen[2][16] = {
     {0, 0, 0, 0, 3, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4},
     {0, 1, 2, 3, 0, 1, 2, 3, 1, 2, 3, 1, 2, 3, 2, 3}
   };
   int numbits;
   int num0 = slen[0][gr_info->scalefac_compress];
   int num1 = slen[1][gr_info->scalefac_compress];

    if (gr_info->block_type == 2) {
      int i=18;
      numbits = (num0 + num1) * 18;

      if (gr_info->mixed_block_flag) {
         for (i=8;i;i--)
           *scf++ = getbits_fast(&bsi,num0);
         i = 9;
         numbits -= num0; /* num0 * 17 + num1 * 18 */
      }

      for (;i;i--)
        *scf++ = getbits_fast(&bsi,num0);
      for (i = 18; i; i--)
        *scf++ = getbits_fast(&bsi,num1);
      *scf++ = 0; *scf++ = 0; *scf++ = 0; /* short[13][0..2] = 0 */
    }
    else {
      int i;
      int scfsi = gr_info->scfsi;

      if(scfsi < 0) { /* scfsi < 0 => granule == 0 */
         for(i=11;i;i--)
           *scf++ = getbits_fast(&bsi,num0);
         for(i=10;i;i--)
           *scf++ = getbits_fast(&bsi,num1);
         numbits = (num0 + num1) * 10 + num0;
         *scf++ = 0;
      }
      else {
        numbits = 0;
        if(!(scfsi & 0x8)) {
          for (i=0;i<6;i++)
            *scf++ = getbits_fast(&bsi,num0);
          numbits += num0 * 6;
        }
        else {
          scf += 6; 
        }

        if(!(scfsi & 0x4)) {
          for (i=0;i<5;i++)
            *scf++ = getbits_fast(&bsi,num0);
          numbits += num0 * 5;
        }
        else {
          scf += 5;
        }

        if(!(scfsi & 0x2)) {
          for(i=0;i<5;i++)
            *scf++ = getbits_fast(&bsi,num1);
          numbits += num1 * 5;
        }
        else {
          scf += 5; 
        }

        if(!(scfsi & 0x1)) {
          for (i=0;i<5;i++)
            *scf++ = getbits_fast(&bsi,num1);
          numbits += num1 * 5;
        }
        else {
           scf += 5;
        }
        *scf++ = 0;  /* no l[21] in original sources */
      }
    }
    return numbits;
}

static int III_get_scale_factors_2(int *scf,struct gr_info_s *gr_info,int i_stereo)
{
  unsigned char *pnt;
  int i,j,n=0,numbits=0;
  unsigned int slen;

  static unsigned char stab[3][6][4] = {
   { { 6, 5, 5,5 } , { 6, 5, 7,3 } , { 11,10,0,0} ,
     { 7, 7, 7,0 } , { 6, 6, 6,3 } , {  8, 8,5,0} } ,
   { { 9, 9, 9,9 } , { 9, 9,12,6 } , { 18,18,0,0} ,
     {12,12,12,0 } , {12, 9, 9,6 } , { 15,12,9,0} } ,
   { { 6, 9, 9,9 } , { 6, 9,12,6 } , { 15,18,0,0} ,
     { 6,15,12,0 } , { 6,12, 9,6 } , {  6,18,9,0} } }; 

  if(i_stereo) /* i_stereo AND second channel -> do_layer3() checks this */
    slen = i_slen2[gr_info->scalefac_compress>>1];
  else
    slen = n_slen2[gr_info->scalefac_compress];

  gr_info->preflag = (slen>>15) & 0x1;

  n = 0;  
  if( gr_info->block_type == 2 ) {
    n++;
    if(gr_info->mixed_block_flag)
      n++;
  }

  pnt = stab[n][(slen>>12)&0x7];

  for(i=0;i<4;i++) {
    int num = slen & 0x7;
    slen >>= 3;
    if(num) {
      for(j=0;j<(int)(pnt[i]);j++)
        *scf++ = getbits_fast(&bsi,num);
      numbits += pnt[i] * num;
    }
    else {
      for(j=0;j<(int)(pnt[i]);j++)
        *scf++ = 0;
    }
  }
  
  n = (n << 1) + 1;
  for(i=0;i<n;i++)
    *scf++ = 0;

  return numbits;
}

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};
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};

/*
 * Dequantize samples (includes huffman decoding)
 */
/* 24 is enough because tab13 has max. a 19 bit huffvector */
#define BITSHIFT ((sizeof(long)-1)*8)
#define REFRESH_MASK \
  while(num < BITSHIFT) { \
    mask |= ((unsigned long)getbyte(&bsi))<<(BITSHIFT-num); \
    num += 8; \
    part2remain -= 8; }

static int III_dequantize_sample(real xr[SBLIMIT][SSLIMIT],int *scf,
   struct gr_info_s *gr_info,int sfreq,int part2bits)
{
  int shift = 1 + gr_info->scalefac_scale;
  real *xrpnt = (real *) xr;
  int l[3],l3;
  int part2remain = gr_info->part2_3_length - part2bits;
  int *me;

  int num=getbitoffset(&bsi);
  long mask;
  /* we must split this, because for num==0 the shift is undefined if you do it in one step */
  mask  = ((unsigned long) getbits(&bsi,num))<<BITSHIFT;
  mask <<= 8-num;
  part2remain -= num;

  {
    int bv       = gr_info->big_values;
    int region1  = gr_info->region1start;
    int region2  = gr_info->region2start;

    l3 = ((576>>1)-bv)>>1;   
/*
 * we may lose the 'odd' bit here !! 
 * check this later again 
 */
    if(bv <= region1) {
      l[0] = bv; l[1] = l[2] = 0;
    }
    else {
      l[0] = region1;
      if(bv <= region2) {
        l[1] = bv - l[0];  l[2] = 0;
      }
      else {
        l[1] = region2 - l[0]; l[2] = bv - region2;
      }
    }
  }
 
  if(gr_info->block_type == 2) {
    /*
     * decoding with short or mixed mode BandIndex table 
     */
    int i,max[4];
    int step=0,lwin=3,cb=0;
    register real v = 0.0;
    register int *m,mc;

    if(gr_info->mixed_block_flag) {
      max[3] = -1;
      max[0] = max[1] = max[2] = 2;
      m = map[sfreq][0];
      me = mapend[sfreq][0];
    }
    else {
      max[0] = max[1] = max[2] = max[3] = -1;
      /* max[3] not really needed in this case */
      m = map[sfreq][1];
      me = mapend[sfreq][1];
    }

    mc = 0;
    for(i=0;i<2;i++) {
      int lp = l[i];
      struct newhuff *h = ht+gr_info->table_select[i];
      for(;lp;lp--,mc--) {
        register int x,y;
        if( (!mc) ) {
          mc    = *m++;
          xrpnt = ((real *) xr) + (*m++);
          lwin  = *m++;
          cb    = *m++;
          if(lwin == 3) {
            v = gr_info->pow2gain[(*scf++) << shift];
            step = 1;
          }
          else {
            v = gr_info->full_gain[lwin][(*scf++) << shift];
            step = 3;
          }
        }
        {
          register short *val = h->table;
          REFRESH_MASK;
          while((y=*val++)<0) {
            if (mask < 0)
              val -= y;
            num--;
            mask <<= 1;
          }
          x = y >> 4;
          y &= 0xf;
        }
        if(x == 15 && h->linbits) {
          max[lwin] = cb;
          REFRESH_MASK;
          x += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
          num -= h->linbits+1;
          mask <<= h->linbits;
          if(mask < 0)
            *xrpnt = REAL_MUL(-ispow[x], v);
          else
            *xrpnt = REAL_MUL(ispow[x], v);
          mask <<= 1;
        }
        else if(x) {
          max[lwin] = cb;
          if(mask < 0)
            *xrpnt = REAL_MUL(-ispow[x], v);
          else
            *xrpnt = REAL_MUL(ispow[x], v);
          num--;
          mask <<= 1;
        }
        else
          *xrpnt = DOUBLE_TO_REAL(0.0);
        xrpnt += step;
        if(y == 15 && h->linbits) {
          max[lwin] = cb;
          REFRESH_MASK;
          y += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
          num -= h->linbits+1;
          mask <<= h->linbits;
          if(mask < 0)
            *xrpnt = REAL_MUL(-ispow[y], v);
          else
            *xrpnt = REAL_MUL(ispow[y], v);
          mask <<= 1;
        }
        else if(y) {
          max[lwin] = cb;
          if(mask < 0)
            *xrpnt = REAL_MUL(-ispow[y], v);
          else
            *xrpnt = REAL_MUL(ispow[y], v);
          num--;
          mask <<= 1;
        }
        else
          *xrpnt = DOUBLE_TO_REAL(0.0);
        xrpnt += step;
      }
    }

    for(;l3 && (part2remain+num > 0);l3--) {
      struct newhuff *h = htc+gr_info->count1table_select;
      register short *val = h->table,a;

      REFRESH_MASK;
      while((a=*val++)<0) {
        if (mask < 0)
          val -= a;
        num--;
        mask <<= 1;
      }
      if(part2remain+num <= 0) {
      num -= part2remain+num;
      break;
      }

      for(i=0;i<4;i++) {
        if(!(i & 1)) {
          if(!mc) {
            mc = *m++;
            xrpnt = ((real *) xr) + (*m++);
            lwin = *m++;
            cb = *m++;
            if(lwin == 3) {
              v = gr_info->pow2gain[(*scf++) << shift];
              step = 1;
            }
            else {
              v = gr_info->full_gain[lwin][(*scf++) << shift];
              step = 3;
            }
          }
          mc--;
        }
        if( (a & (0x8>>i)) ) {
          max[lwin] = cb;
          if(part2remain+num <= 0) {
            break;
          }
          if(mask < 0) 
            *xrpnt = -v;
          else
            *xrpnt = v;
          num--;
          mask <<= 1;
        }
        else
          *xrpnt = DOUBLE_TO_REAL(0.0);
        xrpnt += step;
      }
    }

    if(lwin < 3) { /* short band? */
      while(1) {
        for(;mc > 0;mc--) {
          *xrpnt = DOUBLE_TO_REAL(0.0); xrpnt += 3; /* short band -> step=3 */
          *xrpnt = DOUBLE_TO_REAL(0.0); xrpnt += 3;
        }
        if(m >= me)
          break;
        mc    = *m++;
        xrpnt = ((real *) xr) + *m++;
        if(*m++ == 0)
          break; /* optimize: field will be set to zero at the end of the function */
        m++; /* cb */
      }
    }

    gr_info->maxband[0] = max[0]+1;
    gr_info->maxband[1] = max[1]+1;
    gr_info->maxband[2] = max[2]+1;
    gr_info->maxbandl = max[3]+1;

    {
      int rmax = max[0] > max[1] ? max[0] : max[1];
      rmax = (rmax > max[2] ? rmax : max[2]) + 1;
      gr_info->maxb = rmax ? shortLimit[sfreq][rmax] : longLimit[sfreq][max[3]+1];
    }

  }
  else {
    /*
     * decoding with 'long' BandIndex table (block_type != 2)
     */
    int *pretab = gr_info->preflag ? pretab1 : pretab2;
    int i,max = -1;
    int cb = 0;
    int *m = map[sfreq][2];
    register real v = 0.0;
    int mc = 0;

    /*
     * long hash table values
     */
    for(i=0;i<3;i++) {
      int lp = l[i];
      struct newhuff *h = ht+gr_info->table_select[i];

      for(;lp;lp--,mc--) {
        int x,y;

        if(!mc) {
          mc = *m++;
          cb = *m++;
#ifdef CUT_HF
          if(cb == 21) {
            fprintf(stderr,"c");
            v = 0.0;
          }
          else
#endif
            v = gr_info->pow2gain[((*scf++) + (*pretab++)) << shift];

        }
        {
          register short *val = h->table;
          REFRESH_MASK;
          while((y=*val++)<0) {
            if (mask < 0)
              val -= y;
            num--;
            mask <<= 1;
          }
          x = y >> 4;
          y &= 0xf;
        }

        if (x == 15 && h->linbits) {
          max = cb;
        REFRESH_MASK;
          x += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
          num -= h->linbits+1;
          mask <<= h->linbits;
          if(mask < 0)
            *xrpnt++ = REAL_MUL(-ispow[x], v);
          else
            *xrpnt++ = REAL_MUL(ispow[x], v);
          mask <<= 1;
        }
        else if(x) {
          max = cb;
          if(mask < 0)
            *xrpnt++ = REAL_MUL(-ispow[x], v);
          else
            *xrpnt++ = REAL_MUL(ispow[x], v);
          num--;
          mask <<= 1;
        }
        else
          *xrpnt++ = DOUBLE_TO_REAL(0.0);

        if (y == 15 && h->linbits) {
          max = cb;
        REFRESH_MASK;
          y += ((unsigned long) mask) >> (BITSHIFT+8-h->linbits);
          num -= h->linbits+1;
          mask <<= h->linbits;
          if(mask < 0)
            *xrpnt++ = REAL_MUL(-ispow[y], v);
          else
            *xrpnt++ = REAL_MUL(ispow[y], v);
          mask <<= 1;
        }
        else if(y) {
          max = cb;
          if(mask < 0)
            *xrpnt++ = REAL_MUL(-ispow[y], v);
          else
            *xrpnt++ = REAL_MUL(ispow[y], v);
          num--;
          mask <<= 1;
        }
        else
          *xrpnt++ = DOUBLE_TO_REAL(0.0);
      }
    }

    /*
     * short (count1table) values
     */
    for(;l3 && (part2remain+num > 0);l3--) {
      struct newhuff *h = htc+gr_info->count1table_select;
      register short *val = h->table,a;

      REFRESH_MASK;
      while((a=*val++)<0) {
        if (mask < 0)
          val -= a;
        num--;
        mask <<= 1;
      }
      if(part2remain+num <= 0) {
      num -= part2remain+num;
        break;
      }

      for(i=0;i<4;i++) {
        if(!(i & 1)) {
          if(!mc) {
            mc = *m++;
            cb = *m++;
#ifdef CUT_HF
            if(cb == 21) { 
              fprintf(stderr,"c");
              v = 0.0;
            }
            else
#endif
              v = gr_info->pow2gain[((*scf++) + (*pretab++)) << shift];
          }
          mc--;
        }
        if ( (a & (0x8>>i)) ) {
          max = cb;
          if(part2remain+num <= 0) {
            break;
          }
          if(mask < 0)
            *xrpnt++ = -v;
          else
            *xrpnt++ = v;
          num--;
          mask <<= 1;
        }
        else
          *xrpnt++ = DOUBLE_TO_REAL(0.0);
      }
    }

    gr_info->maxbandl = max+1;
    gr_info->maxb = longLimit[sfreq][gr_info->maxbandl];
  }

  part2remain += num;
  backbits(&bsi,num);
  num = 0;

  while(xrpnt < &xr[SBLIMIT][0]) 
    *xrpnt++ = DOUBLE_TO_REAL(0.0);

  while( part2remain > 16 ) {
    getbits(&bsi,16); /* Dismiss stuffing Bits */
    part2remain -= 16;
  }
  if(part2remain > 0)
    getbits(&bsi,part2remain);
  else if(part2remain < 0) {
    if(param.verbose)
      fprintf(stderr,"mpg123: Can't rewind stream by %d bits!\n",-part2remain);
    return 1; /* -> error */
  }
  return 0;
}

/* 
 * III_stereo: calculate real channel values for Joint-I-Stereo-mode
 */
static void III_i_stereo(real xr_buf[2][SBLIMIT][SSLIMIT],int *scalefac,
   struct gr_info_s *gr_info,int sfreq,int ms_stereo,int lsf)
{
      real (*xr)[SBLIMIT*SSLIMIT] = (real (*)[SBLIMIT*SSLIMIT] ) xr_buf;
      struct bandInfoStruct *bi = &bandInfo[sfreq];

      const real *tab1,*tab2;

      int tab;
      static const real *tabs[3][2][2] = { 
         { { tan1_1,tan2_1 }     , { tan1_2,tan2_2 } },
         { { pow1_1[0],pow2_1[0] } , { pow1_2[0],pow2_2[0] } } ,
         { { pow1_1[1],pow2_1[1] } , { pow1_2[1],pow2_2[1] } } 
      };

      tab = lsf + (gr_info->scalefac_compress & lsf);
      tab1 = tabs[tab][ms_stereo][0];
      tab2 = tabs[tab][ms_stereo][1];
#if 0
      if(lsf) {
        int p = gr_info->scalefac_compress & 0x1;
      if(ms_stereo) {
          tab1 = pow1_2[p]; tab2 = pow2_2[p];
        }
        else {
          tab1 = pow1_1[p]; tab2 = pow2_1[p];
        }
      }
      else {
        if(ms_stereo) {
          tab1 = tan1_2; tab2 = tan2_2;
        }
        else {
          tab1 = tan1_1; tab2 = tan2_1;
        }
      }
#endif

      if (gr_info->block_type == 2) {
         int lwin,do_l = 0;
         if( gr_info->mixed_block_flag )
           do_l = 1;

         for (lwin=0;lwin<3;lwin++) { /* process each window */
             /* get first band with zero values */
           int is_p,sb,idx,sfb = gr_info->maxband[lwin];  /* sfb is minimal 3 for mixed mode */
           if(sfb > 3)
             do_l = 0;

           for(;sfb<12;sfb++) {
             is_p = scalefac[sfb*3+lwin-gr_info->mixed_block_flag]; /* scale: 0-15 */ 
             if(is_p != 7) {
               real t1,t2;
               sb  = bi->shortDiff[sfb];
               idx = bi->shortIdx[sfb] + lwin;
               t1  = tab1[is_p]; t2 = tab2[is_p];
               for (; sb > 0; sb--,idx+=3) {
                 real v = xr[0][idx];
                 xr[0][idx] = REAL_MUL(v, t1);
                 xr[1][idx] = REAL_MUL(v, t2);
               }
             }
           }

#if 1
/* in the original: copy 10 to 11 , here: copy 11 to 12 
maybe still wrong??? (copy 12 to 13?) */
           is_p = scalefac[11*3+lwin-gr_info->mixed_block_flag]; /* scale: 0-15 */
           sb   = bi->shortDiff[12];
           idx  = bi->shortIdx[12] + lwin;
#else
           is_p = scalefac[10*3+lwin-gr_info->mixed_block_flag]; /* scale: 0-15 */
           sb   = bi->shortDiff[11];
           idx  = bi->shortIdx[11] + lwin;
#endif
           if(is_p != 7) {
             real t1,t2;
             t1 = tab1[is_p]; t2 = tab2[is_p];
             for ( ; sb > 0; sb--,idx+=3 ) {  
               real v = xr[0][idx];
               xr[0][idx] = REAL_MUL(v, t1);
               xr[1][idx] = REAL_MUL(v, t2);
             }
           }
         } /* end for(lwin; .. ; . ) */

/* also check l-part, if ALL bands in the three windows are 'empty'
 * and mode = mixed_mode 
 */
         if (do_l) {
           int sfb = gr_info->maxbandl;
           int idx = bi->longIdx[sfb];

           for ( ; sfb<8; sfb++ ) {
             int sb = bi->longDiff[sfb];
             int is_p = scalefac[sfb]; /* scale: 0-15 */
             if(is_p != 7) {
               real t1,t2;
               t1 = tab1[is_p]; t2 = tab2[is_p];
               for ( ; sb > 0; sb--,idx++) {
                 real v = xr[0][idx];
                 xr[0][idx] = REAL_MUL(v, t1);
                 xr[1][idx] = REAL_MUL(v, t2);
               }
             }
             else 
               idx += sb;
           }
         }     
      } 
      else { /* ((gr_info->block_type != 2)) */
       int sfb = gr_info->maxbandl;
       int is_p,idx = bi->longIdx[sfb];

/* hmm ... maybe the maxbandl stuff for i-stereo is buggy? */
       if(sfb <= 21) { 
        for ( ; sfb<21; sfb++) {
          int sb = bi->longDiff[sfb];
          is_p = scalefac[sfb]; /* scale: 0-15 */
          if(is_p != 7) {
            real t1,t2;
            t1 = tab1[is_p]; t2 = tab2[is_p];
            for ( ; sb > 0; sb--,idx++) {
               real v = xr[0][idx];
               xr[0][idx] = REAL_MUL(v, t1);
               xr[1][idx] = REAL_MUL(v, t2);
            }
          }
          else
            idx += sb;
        }

        is_p = scalefac[20];
        if(is_p != 7) {  /* copy l-band 20 to l-band 21 */
          int sb;
          real t1 = tab1[is_p],t2 = tab2[is_p]; 

          for ( sb = bi->longDiff[21]; sb > 0; sb--,idx++ ) {
            real v = xr[0][idx];
            xr[0][idx] = REAL_MUL(v, t1);
            xr[1][idx] = REAL_MUL(v, t2);
          }
        }
       }        /* end: if(sfb <= 21) */
      } /* ... */
}

static void III_antialias(real xr[SBLIMIT][SSLIMIT],struct gr_info_s *gr_info) {
   int sblim;

   if(gr_info->block_type == 2) {
      if(!gr_info->mixed_block_flag) 
        return;
      sblim = 1; 
   }
   else {
     sblim = gr_info->maxb-1;
   }

   /* 31 alias-reduction operations between each pair of sub-bands */
   /* with 8 butterflies between each pair                         */

   {
     int sb;
     real *xr1=(real *) xr[1];

     for(sb=sblim;sb;sb--,xr1+=10) {
       int ss;
       real *cs=aa_cs,*ca=aa_ca;
       real *xr2 = xr1;

       for(ss=7;ss>=0;ss--)
       {       /* upper and lower butterfly inputs */
         register real bu = *--xr2,bd = *xr1;
       *xr2   = REAL_MUL(bu, *cs) - REAL_MUL(bd, *ca);
       *xr1++ = REAL_MUL(bd, *cs++) + REAL_MUL(bu, *ca++);
       }
     }
  }
}

/* 
 This is an optimized DCT from Jeff Tsay's maplay 1.2+ package.
 Saved one multiplication by doing the 'twiddle factor' stuff
 together with the window mul. (MH)

 This uses Byeong Gi Lee's Fast Cosine Transform algorithm, but the
 9 point IDCT needs to be reduced further. Unfortunately, I don't
 know how to do that, because 9 is not an even number. - Jeff.

 ****************************************************************

 9 Point Inverse Discrete Cosine Transform

 This piece of code is Copyright 1997 Mikko Tommila and is freely usable
 by anybody. The algorithm itself is of course in the public domain.

 Again derived heuristically from the 9-point WFTA.

 The algorithm is optimized (?) for speed, not for small rounding errors or
 good readability.

 36 additions, 11 multiplications

 Again this is very likely sub-optimal.

 The code is optimized to use a minimum number of temporary variables,
 so it should compile quite well even on 8-register Intel x86 processors.
 This makes the code quite obfuscated and very difficult to understand.

 References:
 [1] S. Winograd: "On Computing the Discrete Fourier Transform",
     Mathematics of Computation, Volume 32, Number 141, January 1978,
     Pages 175-199
*/

/*------------------------------------------------------------------*/
/*                                                                  */
/*    Function: Calculation of the inverse MDCT                     */
/*                                                                  */
/*------------------------------------------------------------------*/

void dct36(real *inbuf,real *o1,real *o2,real *wintab,real *tsbuf)
{
#ifdef NEW_DCT9
  real tmp[18];
#endif

  {
    register real *in = inbuf;

    in[17]+=in[16]; in[16]+=in[15]; in[15]+=in[14];
    in[14]+=in[13]; in[13]+=in[12]; in[12]+=in[11];
    in[11]+=in[10]; in[10]+=in[9];  in[9] +=in[8];
    in[8] +=in[7];  in[7] +=in[6];  in[6] +=in[5];
    in[5] +=in[4];  in[4] +=in[3];  in[3] +=in[2];
    in[2] +=in[1];  in[1] +=in[0];

    in[17]+=in[15]; in[15]+=in[13]; in[13]+=in[11]; in[11]+=in[9];
    in[9] +=in[7];  in[7] +=in[5];  in[5] +=in[3];  in[3] +=in[1];


#ifdef NEW_DCT9
#if 1
    {
     real t3;
     { 
      real t0, t1, t2;

      t0 = REAL_MUL(COS6_2, (in[8] + in[16] - in[4]));
      t1 = REAL_MUL(COS6_2, in[12]);

      t3 = in[0];
      t2 = t3 - t1 - t1;
      tmp[1] = tmp[7] = t2 - t0;
      tmp[4]          = t2 + t0 + t0;
      t3 += t1;

      t2 = REAL_MUL(COS6_1, (in[10] + in[14] - in[2]));
      tmp[1] -= t2;
      tmp[7] += t2;
     }
     {
      real t0, t1, t2;

      t0 = REAL_MUL(cos9[0], (in[4] + in[8] ));
      t1 = REAL_MUL(cos9[1], (in[8] - in[16]));
      t2 = REAL_MUL(cos9[2], (in[4] + in[16]));

      tmp[2] = tmp[6] = t3 - t0      - t2;
      tmp[0] = tmp[8] = t3 + t0 + t1;
      tmp[3] = tmp[5] = t3      - t1 + t2;
     }
    }
    {
      real t1, t2, t3;

      t1 = REAL_MUL(cos18[0], (in[2]  + in[10]));
      t2 = REAL_MUL(cos18[1], (in[10] - in[14]));
      t3 = REAL_MUL(COS6_1,    in[6]);

      {
        real t0 = t1 + t2 + t3;
        tmp[0] += t0;
        tmp[8] -= t0;
      }

      t2 -= t3;
      t1 -= t3;

      t3 = REAL_MUL(cos18[2], (in[2] + in[14]));

      t1 += t3;
      tmp[3] += t1;
      tmp[5] -= t1;

      t2 -= t3;
      tmp[2] += t2;
      tmp[6] -= t2;
    }

#else
    {
      real t0, t1, t2, t3, t4, t5, t6, t7;

      t1 = REAL_MUL(COS6_2, in[12]);
      t2 = REAL_MUL(COS6_2, (in[8] + in[16] - in[4]));

      t3 = in[0] + t1;
      t4 = in[0] - t1 - t1;
      t5     = t4 - t2;
      tmp[4] = t4 + t2 + t2;

      t0 = REAL_MUL(cos9[0], (in[4] + in[8]));
      t1 = REAL_MUL(cos9[1], (in[8] - in[16]));

      t2 = REAL_MUL(cos9[2], (in[4] + in[16]));

      t6 = t3 - t0 - t2;
      t0 += t3 + t1;
      t3 += t2 - t1;

      t2 = REAL_MUL(cos18[0], (in[2]  + in[10]));
      t4 = REAL_MUL(cos18[1], (in[10] - in[14]));
      t7 = REAL_MUL(COS6_1, in[6]);

      t1 = t2 + t4 + t7;
      tmp[0] = t0 + t1;
      tmp[8] = t0 - t1;
      t1 = REAL_MUL(cos18[2], (in[2] + in[14]));
      t2 += t1 - t7;

      tmp[3] = t3 + t2;
      t0 = REAL_MUL(COS6_1, (in[10] + in[14] - in[2]));
      tmp[5] = t3 - t2;

      t4 -= t1 + t7;

      tmp[1] = t5 - t0;
      tmp[7] = t5 + t0;
      tmp[2] = t6 + t4;
      tmp[6] = t6 - t4;
    }
#endif

    {
      real t0, t1, t2, t3, t4, t5, t6, t7;

      t1 = REAL_MUL(COS6_2, in[13]);
      t2 = REAL_MUL(COS6_2, (in[9] + in[17] - in[5]));

      t3 = in[1] + t1;
      t4 = in[1] - t1 - t1;
      t5 = t4 - t2;

      t0 = REAL_MUL(cos9[0], (in[5] + in[9]));
      t1 = REAL_MUL(cos9[1], (in[9] - in[17]));

      tmp[13] = REAL_MUL((t4 + t2 + t2), tfcos36[17-13]);
      t2 = REAL_MUL(cos9[2], (in[5] + in[17]));

      t6 = t3 - t0 - t2;
      t0 += t3 + t1;
      t3 += t2 - t1;

      t2 = REAL_MUL(cos18[0], (in[3]  + in[11]));
      t4 = REAL_MUL(cos18[1], (in[11] - in[15]));
      t7 = REAL_MUL(COS6_1, in[7]);

      t1 = t2 + t4 + t7;
      tmp[17] = REAL_MUL((t0 + t1), tfcos36[17-17]);
      tmp[9]  = REAL_MUL((t0 - t1), tfcos36[17-9]);
      t1 = REAL_MUL(cos18[2], (in[3] + in[15]));
      t2 += t1 - t7;

      tmp[14] = REAL_MUL((t3 + t2), tfcos36[17-14]);
      t0 = REAL_MUL(COS6_1, (in[11] + in[15] - in[3]));
      tmp[12] = REAL_MUL((t3 - t2), tfcos36[17-12]);

      t4 -= t1 + t7;

      tmp[16] = REAL_MUL((t5 - t0), tfcos36[17-16]);
      tmp[10] = REAL_MUL((t5 + t0), tfcos36[17-10]);
      tmp[15] = REAL_MUL((t6 + t4), tfcos36[17-15]);
      tmp[11] = REAL_MUL((t6 - t4), tfcos36[17-11]);
   }

#define MACRO(v) { \
    real tmpval; \
    tmpval = tmp[(v)] + tmp[17-(v)]; \
    out2[9+(v)] = REAL_MUL(tmpval, w[27+(v)]); \
    out2[8-(v)] = REAL_MUL(tmpval, w[26-(v)]); \
    tmpval = tmp[(v)] - tmp[17-(v)]; \
    ts[SBLIMIT*(8-(v))] = out1[8-(v)] + REAL_MUL(tmpval, w[8-(v)]); \
    ts[SBLIMIT*(9+(v))] = out1[9+(v)] + REAL_MUL(tmpval, w[9+(v)]); }

{
   register real *out2 = o2;
   register real *w = wintab;
   register real *out1 = o1;
   register real *ts = tsbuf;

   MACRO(0);
   MACRO(1);
   MACRO(2);
   MACRO(3);
   MACRO(4);
   MACRO(5);
   MACRO(6);
   MACRO(7);
   MACRO(8);
}

#else

  {

#define MACRO0(v) { \
    real tmp; \
    out2[9+(v)] = REAL_MUL((tmp = sum0 + sum1), w[27+(v)]); \
    out2[8-(v)] = REAL_MUL(tmp, w[26-(v)]);   } \
    sum0 -= sum1; \
    ts[SBLIMIT*(8-(v))] = out1[8-(v)] + REAL_MUL(sum0, w[8-(v)]); \
    ts[SBLIMIT*(9+(v))] = out1[9+(v)] + REAL_MUL(sum0, w[9+(v)]);
#define MACRO1(v) { \
      real sum0,sum1; \
    sum0 = tmp1a + tmp2a; \
      sum1 = REAL_MUL((tmp1b + tmp2b), tfcos36[(v)]); \
      MACRO0(v); }
#define MACRO2(v) { \
    real sum0,sum1; \
    sum0 = tmp2a - tmp1a; \
    sum1 = REAL_MUL((tmp2b - tmp1b), tfcos36[(v)]); \
      MACRO0(v); }

    register const real *c = COS9;
    register real *out2 = o2;
      register real *w = wintab;
      register real *out1 = o1;
      register real *ts = tsbuf;

    real ta33,ta66,tb33,tb66;

    ta33 = REAL_MUL(in[2*3+0], c[3]);
    ta66 = REAL_MUL(in[2*6+0], c[6]);
    tb33 = REAL_MUL(in[2*3+1], c[3]);
    tb66 = REAL_MUL(in[2*6+1], c[6]);

    { 
      real tmp1a,tmp2a,tmp1b,tmp2b;
      tmp1a = REAL_MUL(in[2*1+0], c[1]) + ta33 + REAL_MUL(in[2*5+0], c[5]) + REAL_MUL(in[2*7+0], c[7]);
      tmp1b = REAL_MUL(in[2*1+1], c[1]) + tb33 + REAL_MUL(in[2*5+1], c[5]) + REAL_MUL(in[2*7+1], c[7]);
      tmp2a = REAL_MUL(in[2*2+0], c[2]) + REAL_MUL(in[2*4+0], c[4]) + ta66 + REAL_MUL(in[2*8+0], c[8]);
      tmp2b = REAL_MUL(in[2*2+1], c[2]) + REAL_MUL(in[2*4+1], c[4]) + tb66 + REAL_MUL(in[2*8+1], c[8]);

      MACRO1(0);
      MACRO2(8);
    }

    {
      real tmp1a,tmp2a,tmp1b,tmp2b;
      tmp1a = REAL_MUL(( in[2*1+0] - in[2*5+0] - in[2*7+0] ), c[3]);
      tmp1b = REAL_MUL(( in[2*1+1] - in[2*5+1] - in[2*7+1] ), c[3]);
      tmp2a = REAL_MUL(( in[2*2+0] - in[2*4+0] - in[2*8+0] ), c[6]) - in[2*6+0] + in[2*0+0];
      tmp2b = REAL_MUL(( in[2*2+1] - in[2*4+1] - in[2*8+1] ), c[6]) - in[2*6+1] + in[2*0+1];

      MACRO1(1);
      MACRO2(7);
    }

    {
      real tmp1a,tmp2a,tmp1b,tmp2b;
      tmp1a =   REAL_MUL(in[2*1+0], c[5]) - ta33 - REAL_MUL(in[2*5+0], c[7]) + REAL_MUL(in[2*7+0], c[1]);
      tmp1b =   REAL_MUL(in[2*1+1], c[5]) - tb33 - REAL_MUL(in[2*5+1], c[7]) + REAL_MUL(in[2*7+1], c[1]);
      tmp2a = - REAL_MUL(in[2*2+0], c[8]) - REAL_MUL(in[2*4+0], c[2]) + ta66 + REAL_MUL(in[2*8+0], c[4]);
      tmp2b = - REAL_MUL(in[2*2+1], c[8]) - REAL_MUL(in[2*4+1], c[2]) + tb66 + REAL_MUL(in[2*8+1], c[4]);

      MACRO1(2);
      MACRO2(6);
    }

    {
      real tmp1a,tmp2a,tmp1b,tmp2b;
      tmp1a =   REAL_MUL(in[2*1+0], c[7]) - ta33 + REAL_MUL(in[2*5+0], c[1]) - REAL_MUL(in[2*7+0], c[5]);
      tmp1b =   REAL_MUL(in[2*1+1], c[7]) - tb33 + REAL_MUL(in[2*5+1], c[1]) - REAL_MUL(in[2*7+1], c[5]);
      tmp2a = - REAL_MUL(in[2*2+0], c[4]) + REAL_MUL(in[2*4+0], c[8]) + ta66 - REAL_MUL(in[2*8+0], c[2]);
      tmp2b = - REAL_MUL(in[2*2+1], c[4]) + REAL_MUL(in[2*4+1], c[8]) + tb66 - REAL_MUL(in[2*8+1], c[2]);

      MACRO1(3);
      MACRO2(5);
    }

      {
            real sum0,sum1;
      sum0 =  in[2*0+0] - in[2*2+0] + in[2*4+0] - in[2*6+0] + in[2*8+0];
      sum1 = REAL_MUL((in[2*0+1] - in[2*2+1] + in[2*4+1] - in[2*6+1] + in[2*8+1] ), tfcos36[4]);
            MACRO0(4);
      }
  }
#endif

  }
}

/*
 * new DCT12
 */
static void dct12(real *in,real *rawout1,real *rawout2,register real *wi,register real *ts)
{
#define DCT12_PART1 \
             in5 = in[5*3];  \
     in5 += (in4 = in[4*3]); \
     in4 += (in3 = in[3*3]); \
     in3 += (in2 = in[2*3]); \
     in2 += (in1 = in[1*3]); \
     in1 += (in0 = in[0*3]); \
                             \
     in5 += in3; in3 += in1; \
                             \
     in2 = REAL_MUL(in2, COS6_1); \
     in3 = REAL_MUL(in3, COS6_1); \

#define DCT12_PART2 \
     in0 += REAL_MUL(in4, COS6_2); \
                          \
     in4 = in0 + in2;     \
     in0 -= in2;          \
                          \
     in1 += REAL_MUL(in5, COS6_2); \
                          \
     in5 = REAL_MUL((in1 + in3), tfcos12[0]); \
     in1 = REAL_MUL((in1 - in3), tfcos12[2]); \
                         \
     in3 = in4 + in5;    \
     in4 -= in5;         \
                         \
     in2 = in0 + in1;    \
     in0 -= in1;


   {
     real in0,in1,in2,in3,in4,in5;
     register real *out1 = rawout1;
     ts[SBLIMIT*0] = out1[0]; ts[SBLIMIT*1] = out1[1]; ts[SBLIMIT*2] = out1[2];
     ts[SBLIMIT*3] = out1[3]; ts[SBLIMIT*4] = out1[4]; ts[SBLIMIT*5] = out1[5];
 
     DCT12_PART1

     {
       real tmp0,tmp1 = (in0 - in4);
       {
         real tmp2 = REAL_MUL((in1 - in5), tfcos12[1]);
         tmp0 = tmp1 + tmp2;
         tmp1 -= tmp2;
       }
       ts[(17-1)*SBLIMIT] = out1[17-1] + REAL_MUL(tmp0, wi[11-1]);
       ts[(12+1)*SBLIMIT] = out1[12+1] + REAL_MUL(tmp0, wi[6+1]);
       ts[(6 +1)*SBLIMIT] = out1[6 +1] + REAL_MUL(tmp1, wi[1]);
       ts[(11-1)*SBLIMIT] = out1[11-1] + REAL_MUL(tmp1, wi[5-1]);
     }

     DCT12_PART2

     ts[(17-0)*SBLIMIT] = out1[17-0] + REAL_MUL(in2, wi[11-0]);
     ts[(12+0)*SBLIMIT] = out1[12+0] + REAL_MUL(in2, wi[6+0]);
     ts[(12+2)*SBLIMIT] = out1[12+2] + REAL_MUL(in3, wi[6+2]);
     ts[(17-2)*SBLIMIT] = out1[17-2] + REAL_MUL(in3, wi[11-2]);

     ts[(6 +0)*SBLIMIT]  = out1[6+0] + REAL_MUL(in0, wi[0]);
     ts[(11-0)*SBLIMIT] = out1[11-0] + REAL_MUL(in0, wi[5-0]);
     ts[(6 +2)*SBLIMIT]  = out1[6+2] + REAL_MUL(in4, wi[2]);
     ts[(11-2)*SBLIMIT] = out1[11-2] + REAL_MUL(in4, wi[5-2]);
  }

  in++;

  {
     real in0,in1,in2,in3,in4,in5;
     register real *out2 = rawout2;
 
     DCT12_PART1

     {
       real tmp0,tmp1 = (in0 - in4);
       {
         real tmp2 = REAL_MUL((in1 - in5), tfcos12[1]);
         tmp0 = tmp1 + tmp2;
         tmp1 -= tmp2;
       }
       out2[5-1] = REAL_MUL(tmp0, wi[11-1]);
       out2[0+1] = REAL_MUL(tmp0, wi[6+1]);
       ts[(12+1)*SBLIMIT] += REAL_MUL(tmp1, wi[1]);
       ts[(17-1)*SBLIMIT] += REAL_MUL(tmp1, wi[5-1]);
     }

     DCT12_PART2

     out2[5-0] = REAL_MUL(in2, wi[11-0]);
     out2[0+0] = REAL_MUL(in2, wi[6+0]);
     out2[0+2] = REAL_MUL(in3, wi[6+2]);
     out2[5-2] = REAL_MUL(in3, wi[11-2]);

     ts[(12+0)*SBLIMIT] += REAL_MUL(in0, wi[0]);
     ts[(17-0)*SBLIMIT] += REAL_MUL(in0, wi[5-0]);
     ts[(12+2)*SBLIMIT] += REAL_MUL(in4, wi[2]);
     ts[(17-2)*SBLIMIT] += REAL_MUL(in4, wi[5-2]);
  }

  in++; 

  {
     real in0,in1,in2,in3,in4,in5;
     register real *out2 = rawout2;
     out2[12]=out2[13]=out2[14]=out2[15]=out2[16]=out2[17]=0.0;

     DCT12_PART1

     {
       real tmp0,tmp1 = (in0 - in4);
       {
         real tmp2 = REAL_MUL((in1 - in5), tfcos12[1]);
         tmp0 = tmp1 + tmp2;
         tmp1 -= tmp2;
       }
       out2[11-1] = REAL_MUL(tmp0, wi[11-1]);
       out2[6 +1] = REAL_MUL(tmp0, wi[6+1]);
       out2[0+1] += REAL_MUL(tmp1, wi[1]);
       out2[5-1] += REAL_MUL(tmp1, wi[5-1]);
     }

     DCT12_PART2

     out2[11-0] = REAL_MUL(in2, wi[11-0]);
     out2[6 +0] = REAL_MUL(in2, wi[6+0]);
     out2[6 +2] = REAL_MUL(in3, wi[6+2]);
     out2[11-2] = REAL_MUL(in3, wi[11-2]);

     out2[0+0] += REAL_MUL(in0, wi[0]);
     out2[5-0] += REAL_MUL(in0, wi[5-0]);
     out2[0+2] += REAL_MUL(in4, wi[2]);
     out2[5-2] += REAL_MUL(in4, wi[5-2]);
  }
}

/*
 * III_hybrid
 */
static void III_hybrid(struct mpstr *mp,real fsIn[SBLIMIT][SSLIMIT],real tsOut[SSLIMIT][SBLIMIT],
   int ch,struct gr_info_s *gr_info,struct frame *fr)
{
/*
   static real block[2][2][SBLIMIT*SSLIMIT] = { { { 0, } } };
   static int blc[2]={0,0};
 */

   real *tspnt = (real *) tsOut;
   real *rawout1,*rawout2;
   int bt,sb = 0;

   {
     int b = mp->hybrid_blc[ch];
     rawout1=mp->hybrid_block[b][ch];
     b=-b+1;
     rawout2=mp->hybrid_block[b][ch];
     mp->hybrid_blc[ch] = b;
   }
  
   if(gr_info->mixed_block_flag) {
     sb = 2;
#ifdef USE_3DNOW
     (fr->dct36)(fsIn[0],rawout1,rawout2,win[0],tspnt);
     (fr->dct36)(fsIn[1],rawout1+18,rawout2+18,win1[0],tspnt+1);
#else
     dct36(fsIn[0],rawout1,rawout2,win[0],tspnt);
     dct36(fsIn[1],rawout1+18,rawout2+18,win1[0],tspnt+1);
#endif
     rawout1 += 36; rawout2 += 36; tspnt += 2;
   }
 
   bt = gr_info->block_type;
   if(bt == 2) {
     for (; sb<gr_info->maxb; sb+=2,tspnt+=2,rawout1+=36,rawout2+=36) {
       dct12(fsIn[sb]  ,rawout1   ,rawout2   ,win[2] ,tspnt);
       dct12(fsIn[sb+1],rawout1+18,rawout2+18,win1[2],tspnt+1);
     }
   }
   else {
     for (; sb<gr_info->maxb; sb+=2,tspnt+=2,rawout1+=36,rawout2+=36) {
#ifdef USE_3DNOW
       (fr->dct36)(fsIn[sb],rawout1,rawout2,win[bt],tspnt);
       (fr->dct36)(fsIn[sb+1],rawout1+18,rawout2+18,win1[bt],tspnt+1);
#else
       dct36(fsIn[sb],rawout1,rawout2,win[bt],tspnt);
       dct36(fsIn[sb+1],rawout1+18,rawout2+18,win1[bt],tspnt+1);
#endif
     }
   }

   for(;sb<SBLIMIT;sb++,tspnt++) {
     int i;
     for(i=0;i<SSLIMIT;i++) {
       tspnt[i*SBLIMIT] = *rawout1++;
       *rawout2++ = DOUBLE_TO_REAL(0.0);
     }
   }
}



/*
 * main layer3 handler
 */
int do_layer3(struct mpstr *mp,struct frame *fr,int outmode,struct audio_info_struct *ai)
{
  int gr, ch, ss,clip=0;
  int scalefacs[2][39]; /* max 39 for short[13][3] mode, mixed: 38, long: 22 */
  struct III_sideinfo sideinfo;
  int stereo = fr->stereo;
  int single = fr->single;
  int ms_stereo,i_stereo;
  int sfreq = fr->sampling_frequency;
  int stereo1,granules;

  if(stereo == 1) { /* stream is mono */
    stereo1 = 1;
    single = 0;
  }
  else if(single >= 0) /* stream is stereo, but force to mono */
    stereo1 = 1;
  else
    stereo1 = 2;

  if(fr->mode == MPG_MD_JOINT_STEREO) {
    ms_stereo = (fr->mode_ext & 0x2)>>1;
    i_stereo  = fr->mode_ext & 0x1;
  }
  else
    ms_stereo = i_stereo = 0;

  granules = fr->lsf ? 1 : 2;
  if(!III_get_side_info(&sideinfo,stereo,ms_stereo,sfreq,single,fr->lsf))
    return -1;

  set_pointer(fr->sideInfoSize,sideinfo.main_data_begin);

  for (gr=0;gr<granules;gr++) {
    real hybridIn [2][SBLIMIT][SSLIMIT];
    real hybridOut[2][SSLIMIT][SBLIMIT];

    {
      struct gr_info_s *gr_info = &(sideinfo.ch[0].gr[gr]);
      long part2bits;
      if(fr->lsf)
        part2bits = III_get_scale_factors_2(scalefacs[0],gr_info,0);
      else
        part2bits = III_get_scale_factors_1(scalefacs[0],gr_info);

      if(III_dequantize_sample(hybridIn[0], scalefacs[0],gr_info,sfreq,part2bits))
        return clip;
    }

    if(stereo == 2) {
      struct gr_info_s *gr_info = &(sideinfo.ch[1].gr[gr]);
      long part2bits;
      if(fr->lsf) 
        part2bits = III_get_scale_factors_2(scalefacs[1],gr_info,i_stereo);
      else
        part2bits = III_get_scale_factors_1(scalefacs[1],gr_info);

      if(III_dequantize_sample(hybridIn[1],scalefacs[1],gr_info,sfreq,part2bits))
          return clip;

      if(ms_stereo) {
        int i;
        int maxb = sideinfo.ch[0].gr[gr].maxb;
        if(sideinfo.ch[1].gr[gr].maxb > maxb)
            maxb = sideinfo.ch[1].gr[gr].maxb;
        for(i=0;i<SSLIMIT*maxb;i++) {
          real tmp0 = ((real *)hybridIn[0])[i];
          real tmp1 = ((real *)hybridIn[1])[i];
          ((real *)hybridIn[0])[i] = tmp0 + tmp1;
          ((real *)hybridIn[1])[i] = tmp0 - tmp1;
        }
      }

      if(i_stereo)
        III_i_stereo(hybridIn,scalefacs[1],gr_info,sfreq,ms_stereo,fr->lsf);

      if(ms_stereo || i_stereo || (single == 3) ) {
        if(gr_info->maxb > sideinfo.ch[0].gr[gr].maxb) 
          sideinfo.ch[0].gr[gr].maxb = gr_info->maxb;
        else
          gr_info->maxb = sideinfo.ch[0].gr[gr].maxb;
      }

      switch(single) {
        case 3:
          {
            register int i;
            register real *in0 = (real *) hybridIn[0],*in1 = (real *) hybridIn[1];
            for(i=0;i<SSLIMIT*gr_info->maxb;i++,in0++)
              *in0 = (*in0 + *in1++); /* *0.5 done by pow-scale */ 
          }
          break;
        case 1:
          {
            register int i;
            register real *in0 = (real *) hybridIn[0],*in1 = (real *) hybridIn[1];
            for(i=0;i<SSLIMIT*gr_info->maxb;i++)
              *in0++ = *in1++;
          }
          break;
      }
    }

    for(ch=0;ch<stereo1;ch++) {
      struct gr_info_s *gr_info = &(sideinfo.ch[ch].gr[gr]);
      III_antialias(hybridIn[ch],gr_info);
      III_hybrid(mp,hybridIn[ch], hybridOut[ch], ch,gr_info,fr);
    }

#ifdef I486_OPT
    if (fr->synth != synth_1to1 || single >= 0) {
#endif
    for(ss=0;ss<SSLIMIT;ss++) {
      if(single >= 0) {
        clip += (fr->synth_mono)(hybridOut[0][ss],pcm_sample,&pcm_point);
      }
      else {
        int p1 = pcm_point;
        clip += (fr->synth)(hybridOut[0][ss],0,pcm_sample,&p1);
        clip += (fr->synth)(hybridOut[1][ss],1,pcm_sample,&pcm_point);
      }

      if(pcm_point >= audiobufsize)
        audio_flush(outmode,ai);
    }
#ifdef I486_OPT
    } else {
      /* Only stereo, 16 bits benefit from the 486 optimization. */
      ss=0;
      while (ss < SSLIMIT) {
        int n;
        n=(audiobufsize - pcm_point) / (2*2*32);
        if (n > (SSLIMIT-ss)) n=SSLIMIT-ss;
        
        synth_1to1_486(hybridOut[0][ss],0,pcm_sample+pcm_point,n);
        synth_1to1_486(hybridOut[1][ss],1,pcm_sample+pcm_point,n);
        ss+=n;
        pcm_point+=(2*2*32)*n;
        
        if(pcm_point >= audiobufsize)
          audio_flush(outmode,ai);
      }
    }
#endif
  }
  
  return clip;
}

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