static void
kf_bfly4 (kiss_fft_s16_cpx * Fout,
    const size_t fstride, const kiss_fft_s16_cfg st, const size_t m)
{
  kiss_fft_s16_cpx *tw1, *tw2, *tw3;
  kiss_fft_s16_cpx scratch[6];
  size_t k = m;
  const size_t m2 = 2 * m;
  const size_t m3 = 3 * m;

  tw3 = tw2 = tw1 = st->twiddles;

  do {
    C_FIXDIV (*Fout, 4);
    C_FIXDIV (Fout[m], 4);
    C_FIXDIV (Fout[m2], 4);
    C_FIXDIV (Fout[m3], 4);

    C_MUL (scratch[0], Fout[m], *tw1);
    C_MUL (scratch[1], Fout[m2], *tw2);
    C_MUL (scratch[2], Fout[m3], *tw3);

    C_SUB (scratch[5], *Fout, scratch[1]);
    C_ADDTO (*Fout, scratch[1]);
    C_ADD (scratch[3], scratch[0], scratch[2]);
    C_SUB (scratch[4], scratch[0], scratch[2]);
    C_SUB (Fout[m2], *Fout, scratch[3]);
    tw1 += fstride;
    tw2 += fstride * 2;
    tw3 += fstride * 3;
    C_ADDTO (*Fout, scratch[3]);

    if (st->inverse) {
      Fout[m].r = scratch[5].r - scratch[4].i;
      Fout[m].i = scratch[5].i + scratch[4].r;
      Fout[m3].r = scratch[5].r + scratch[4].i;
      Fout[m3].i = scratch[5].i - scratch[4].r;
    } else {
      Fout[m].r = scratch[5].r + scratch[4].i;
      Fout[m].i = scratch[5].i - scratch[4].r;
      Fout[m3].r = scratch[5].r - scratch[4].i;
      Fout[m3].i = scratch[5].i + scratch[4].r;
    }
    ++Fout;
  } while (--k);
}
Exemple #2
0
static void ki_bfly4(
                     kiss_fft_cpx * Fout,
                     const size_t fstride,
                     const kiss_fft_state *st,
                     int m,
                     int N,
                     int mm
                    )
{
   const kiss_twiddle_cpx *tw1,*tw2,*tw3;
   kiss_fft_cpx scratch[6];
   const size_t m2=2*m;
   const size_t m3=3*m;
   int i, j;

   kiss_fft_cpx * Fout_beg = Fout;
   for (i=0;i<N;i++)
   {
      Fout = Fout_beg + i*mm;
      tw3 = tw2 = tw1 = st->twiddles;
      for (j=0;j<m;j++)
      {
         C_MULC(scratch[0],Fout[m] , *tw1 );
         C_MULC(scratch[1],Fout[m2] , *tw2 );
         C_MULC(scratch[2],Fout[m3] , *tw3 );
             
         C_SUB( scratch[5] , *Fout, scratch[1] );
         C_ADDTO(*Fout, scratch[1]);
         C_ADD( scratch[3] , scratch[0] , scratch[2] );
         C_SUB( scratch[4] , scratch[0] , scratch[2] );
         C_SUB( Fout[m2], *Fout, scratch[3] );
         tw1 += fstride;
         tw2 += fstride*2;
         tw3 += fstride*3;
         C_ADDTO( *Fout , scratch[3] );
             
         Fout[m].r = scratch[5].r - scratch[4].i;
         Fout[m].i = scratch[5].i + scratch[4].r;
         Fout[m3].r = scratch[5].r + scratch[4].i;
         Fout[m3].i = scratch[5].i - scratch[4].r;
         ++Fout;
      }
   }
}
static void kf_bfly2(
        kiss_fft_cpx * Fout,
        const size_t fstride,
        const kiss_fft_cfg st,
        int m,
        int N,
        int mm
        )
{
    kiss_fft_cpx * Fout2;
    kiss_fft_cpx * tw1;
    kiss_fft_cpx t;
    if (!st->inverse) {
       int i,j;
       kiss_fft_cpx * Fout_beg = Fout;
       for (i=0;i<N;i++)
       {
          Fout = Fout_beg + i*mm;
          Fout2 = Fout + m;
          tw1 = st->twiddles;
          for(j=0;j<m;j++)
          {
             /* Almost the same as the code path below, except that we divide the input by two
              (while keeping the best accuracy possible) */
             ms_word32_t tr, ti;
             tr = SHR32(SUB32(MULT16_16(Fout2->r , tw1->r),MULT16_16(Fout2->i , tw1->i)), 1);
             ti = SHR32(ADD32(MULT16_16(Fout2->i , tw1->r),MULT16_16(Fout2->r , tw1->i)), 1);
             tw1 += fstride;
             Fout2->r = PSHR32(SUB32(SHL32(EXTEND32(Fout->r), 14), tr), 15);
             Fout2->i = PSHR32(SUB32(SHL32(EXTEND32(Fout->i), 14), ti), 15);
             Fout->r = PSHR32(ADD32(SHL32(EXTEND32(Fout->r), 14), tr), 15);
             Fout->i = PSHR32(ADD32(SHL32(EXTEND32(Fout->i), 14), ti), 15);
             ++Fout2;
             ++Fout;
          }
       }
    } else {
       int i,j;
       kiss_fft_cpx * Fout_beg = Fout;
       for (i=0;i<N;i++)
       {
          Fout = Fout_beg + i*mm;
          Fout2 = Fout + m;
          tw1 = st->twiddles;
          for(j=0;j<m;j++)
          {
             C_MUL (t,  *Fout2 , *tw1);
             tw1 += fstride;
             C_SUB( *Fout2 ,  *Fout , t );
             C_ADDTO( *Fout ,  t );
             ++Fout2;
             ++Fout;
          }
       }
    }
}
static void kf_bfly3(
                     kiss_fft_cpx * Fout,
                     const size_t fstride,
                     const kiss_fft_state *st,
                     int m,
                     int N,
                     int mm
                    )
{
   int i;
   size_t k;
   const size_t m2 = 2*m;
   const kiss_twiddle_cpx *tw1,*tw2;
   kiss_fft_cpx scratch[5];
   kiss_twiddle_cpx epi3;

   kiss_fft_cpx * Fout_beg = Fout;
#ifdef FIXED_POINT
   /*epi3.r = -16384;*/ /* Unused */
   epi3.i = -28378;
#else
   epi3 = st->twiddles[fstride*m];
#endif
   for (i=0;i<N;i++)
   {
      Fout = Fout_beg + i*mm;
      tw1=tw2=st->twiddles;
      /* For non-custom modes, m is guaranteed to be a multiple of 4. */
      k=m;
      do {

         C_MUL(scratch[1],Fout[m] , *tw1);
         C_MUL(scratch[2],Fout[m2] , *tw2);

         C_ADD(scratch[3],scratch[1],scratch[2]);
         C_SUB(scratch[0],scratch[1],scratch[2]);
         tw1 += fstride;
         tw2 += fstride*2;

         Fout[m].r = SUB32_ovflw(Fout->r, HALF_OF(scratch[3].r));
         Fout[m].i = SUB32_ovflw(Fout->i, HALF_OF(scratch[3].i));

         C_MULBYSCALAR( scratch[0] , epi3.i );

         C_ADDTO(*Fout,scratch[3]);

         Fout[m2].r = ADD32_ovflw(Fout[m].r, scratch[0].i);
         Fout[m2].i = SUB32_ovflw(Fout[m].i, scratch[0].r);

         Fout[m].r = SUB32_ovflw(Fout[m].r, scratch[0].i);
         Fout[m].i = ADD32_ovflw(Fout[m].i, scratch[0].r);

         ++Fout;
      } while(--k);
   }
}
Exemple #5
0
static void kf_bfly3(
                     kiss_fft_cpx * Fout,
                     const size_t fstride,
                     const kiss_fft_state *st,
                     int m,
                     int N,
                     int mm
                    )
{
   int i;
   size_t k;
   const size_t m2 = 2*m;
   const kiss_twiddle_cpx *tw1,*tw2;
   kiss_fft_cpx scratch[5];
   kiss_twiddle_cpx epi3;

   kiss_fft_cpx * Fout_beg = Fout;
   epi3 = st->twiddles[fstride*m];
   for (i=0;i<N;i++)
   {
      Fout = Fout_beg + i*mm;
      tw1=tw2=st->twiddles;
      k=m;
      do {
         C_FIXDIV(*Fout,3); C_FIXDIV(Fout[m],3); C_FIXDIV(Fout[m2],3);

         C_MUL(scratch[1],Fout[m] , *tw1);
         C_MUL(scratch[2],Fout[m2] , *tw2);

         C_ADD(scratch[3],scratch[1],scratch[2]);
         C_SUB(scratch[0],scratch[1],scratch[2]);
         tw1 += fstride;
         tw2 += fstride*2;

         Fout[m].r = Fout->r - HALF_OF(scratch[3].r);
         Fout[m].i = Fout->i - HALF_OF(scratch[3].i);

         C_MULBYSCALAR( scratch[0] , epi3.i );

         C_ADDTO(*Fout,scratch[3]);

         Fout[m2].r = Fout[m].r + scratch[0].i;
         Fout[m2].i = Fout[m].i - scratch[0].r;

         Fout[m].r -= scratch[0].i;
         Fout[m].i += scratch[0].r;

         ++Fout;
      } while(--k);
   }
}
Exemple #6
0
static void kf_bfly3(
    kiss_fft_cpx * Fout,
    const size_t fstride,
    const kiss_fft_cfg st,
    size_t m
)
{
    size_t k=m;
    const size_t m2 = 2*m;
    kiss_fft_cpx *tw1,*tw2;
    kiss_fft_cpx scratch[5];
    kiss_fft_cpx epi3;
    epi3 = st->twiddles[fstride*m];

    tw1=tw2=st->twiddles;

    do {
        if (!st->inverse) {
            C_FIXDIV(*Fout,3);
            C_FIXDIV(Fout[m],3);
            C_FIXDIV(Fout[m2],3);
        }

        C_MUL(scratch[1],Fout[m] , *tw1);
        C_MUL(scratch[2],Fout[m2] , *tw2);

        C_ADD(scratch[3],scratch[1],scratch[2]);
        C_SUB(scratch[0],scratch[1],scratch[2]);
        tw1 += fstride;
        tw2 += fstride*2;

        Fout[m].r = Fout->r - HALF_OF(scratch[3].r);
        Fout[m].i = Fout->i - HALF_OF(scratch[3].i);

        C_MULBYSCALAR( scratch[0] , epi3.i );

        C_ADDTO(*Fout,scratch[3]);

        Fout[m2].r = Fout[m].r + scratch[0].i;
        Fout[m2].i = Fout[m].i - scratch[0].r;

        Fout[m].r -= scratch[0].i;
        Fout[m].i += scratch[0].r;

        ++Fout;
    } while(--k);
}
Exemple #7
0
static void kf_bfly2(kiss_fft_cpx *Fout, const size_t fstride,
                     const kiss_fft_cfg st, int m) {
  kiss_fft_cpx *Fout2;
  kiss_fft_cpx *tw1 = st->twiddles;
  kiss_fft_cpx t;
  Fout2 = Fout + m;
  do {
    C_FIXDIV(*Fout, 2);
    C_FIXDIV(*Fout2, 2);

    C_MUL(t, *Fout2, *tw1);
    tw1 += fstride;
    C_SUB(*Fout2, *Fout, t);
    C_ADDTO(*Fout, t);
    ++Fout2;
    ++Fout;
  } while (--m);
}
/* perform the butterfly for one stage of a mixed radix FFT */
static void kf_bfly_generic(
        kiss_fft_cpx * Fout,
        const size_t fstride,
        const kiss_fft_cfg st,
        int m,
        int p
        )
{
    int u,k,q1,q;
    kiss_fft_cpx * twiddles = st->twiddles;
    kiss_fft_cpx t;
    kiss_fft_cpx scratchbuf[17];
    int Norig = st->nfft;

    /*CHECKBUF(scratchbuf,nscratchbuf,p);*/
    if (p>17)
       ms_fatal("KissFFT: max radix supported is 17");
    
    for ( u=0; u<m; ++u ) {
        k=u;
        for ( q1=0 ; q1<p ; ++q1 ) {
            scratchbuf[q1] = Fout[ k  ];
        if (!st->inverse) {
            C_FIXDIV(scratchbuf[q1],p);
	}
            k += m;
        }

        k=u;
        for ( q1=0 ; q1<p ; ++q1 ) {
            int twidx=0;
            Fout[ k ] = scratchbuf[0];
            for (q=1;q<p;++q ) {
                twidx += fstride * k;
                if (twidx>=Norig) twidx-=Norig;
                C_MUL(t,scratchbuf[q] , twiddles[twidx] );
                C_ADDTO( Fout[ k ] ,t);
            }
            k += m;
        }
    }
}
Exemple #9
0
/* perform the butterfly for one stage of a mixed radix FFT */
static void kf_bfly_generic(
        kiss_fft_cpx * Fout,
        const size_t fstride,
        const kiss_fft_cfg st,
        int m,
        int p
        )
{
    int u,k,q1,q;
    kiss_fft_cpx * twiddles = st->twiddles;
    kiss_fft_cpx t;
    int Norig = st->nfft;

    kiss_fft_cpx * scratch = (kiss_fft_cpx*)KISS_FFT_TMP_ALLOC(sizeof(kiss_fft_cpx)*p);

    // see http://sourceforge.net/p/kissfft/bugs/9/
    #pragma omp critical
    for ( u=0; u<m; ++u ) {
        k=u;
        for ( q1=0 ; q1<p ; ++q1 ) {
            scratch[q1] = Fout[ k  ];
            C_FIXDIV(scratch[q1],p);
            k += m;
        }

        k=u;
        for ( q1=0 ; q1<p ; ++q1 ) {
            int twidx=0;
            Fout[ k ] = scratch[0];
            for (q=1;q<p;++q ) {
                twidx += fstride * k;
                if (twidx>=Norig) twidx-=Norig;
                C_MUL(t,scratch[q] , twiddles[twidx] );
                C_ADDTO( Fout[ k ] ,t);
            }
            k += m;
        }
    }
    KISS_FFT_TMP_FREE(scratch);
}
Exemple #10
0
/* perform the butterfly for one stage of a mixed radix FFT */
static void kf_bfly_generic(
    kiss_fft_cpx * Fout,
    const size_t fstride,
    const kiss_fft_cfg st,
    int m,
    int p
)
{
    int u,k,q1,q;
    kiss_fft_cpx * twiddles = st->twiddles;
    kiss_fft_cpx t;
    int Norig = st->nfft;

    kiss_fft_cpx *scratchbuf=(kiss_fft_cpx *)malloc( sizeof(kiss_fft_cpx) * p );

    for ( u=0; u<m; ++u ) {
        k=u;
        for ( q1=0 ; q1<p ; ++q1 ) {
            scratchbuf[q1] = Fout[ k  ];
            C_FIXDIV(scratchbuf[q1],p);
            k += m;
        }

        k=u;
        for ( q1=0 ; q1<p ; ++q1 ) {
            int twidx=0;
            Fout[ k ] = scratchbuf[0];
            for (q=1; q<p; ++q ) {
                twidx += fstride * k;
                if (twidx>=Norig) twidx-=Norig;
                C_MUL(t,scratchbuf[q] , twiddles[twidx] );
                C_ADDTO( Fout[ k ] ,t);
            }
            k += m;
        }
    }

    free( scratchbuf );
}
Exemple #11
0
static void kf_bfly4(
    kiss_fft_cpx * Fout,
    const size_t fstride,
    const kiss_fft_cfg st,
    const size_t m
)
{
    kiss_fft_cpx *tw1,*tw2,*tw3;
    kiss_fft_cpx scratch[6];
    size_t k=m;
    const size_t m2=2*m;
    const size_t m3=3*m;

    tw3 = tw2 = tw1 = st->twiddles;

    if (!st->inverse) {
        int i;
        kiss_fft_cpx *x=Fout;
        for (i=0; i<4*m; i++)
        {
            //C_FIXDIV(x[i],4);
            x[i].r = PSHR16(x[i].r,2);
            x[i].i = PSHR16(x[i].i,2);
        }
    }
    if (st->inverse)
    {
        do {
            C_MUL(scratch[0],Fout[m] , *tw1 );
            C_MUL(scratch[1],Fout[m2] , *tw2 );
            C_MUL(scratch[2],Fout[m3] , *tw3 );

            C_SUB( scratch[5] , *Fout, scratch[1] );
            C_ADDTO(*Fout, scratch[1]);
            C_ADD( scratch[3] , scratch[0] , scratch[2] );
            C_SUB( scratch[4] , scratch[0] , scratch[2] );
            C_SUB( Fout[m2], *Fout, scratch[3] );
            tw1 += fstride;
            tw2 += fstride*2;
            tw3 += fstride*3;
            C_ADDTO( *Fout , scratch[3] );

            Fout[m].r = scratch[5].r - scratch[4].i;
            Fout[m].i = scratch[5].i + scratch[4].r;
            Fout[m3].r = scratch[5].r + scratch[4].i;
            Fout[m3].i = scratch[5].i - scratch[4].r;
            ++Fout;
        } while(--k);
    } else
    {
        do {
            C_MUL(scratch[0],Fout[m] , *tw1 );
            C_MUL(scratch[1],Fout[m2] , *tw2 );
            C_MUL(scratch[2],Fout[m3] , *tw3 );

            C_SUB( scratch[5] , *Fout, scratch[1] );
            C_ADDTO(*Fout, scratch[1]);
            C_ADD( scratch[3] , scratch[0] , scratch[2] );
            C_SUB( scratch[4] , scratch[0] , scratch[2] );
            C_SUB( Fout[m2], *Fout, scratch[3] );
            tw1 += fstride;
            tw2 += fstride*2;
            tw3 += fstride*3;
            C_ADDTO( *Fout , scratch[3] );

            Fout[m].r = scratch[5].r + scratch[4].i;
            Fout[m].i = scratch[5].i - scratch[4].r;
            Fout[m3].r = scratch[5].r - scratch[4].i;
            Fout[m3].i = scratch[5].i + scratch[4].r;
            ++Fout;
        } while(--k);
    }
}
static void kf_bfly4(
                     kiss_fft_cpx * Fout,
                     const size_t fstride,
                     const kiss_fft_state *st,
                     int m,
                     int N,
                     int mm
                    )
{
   int i;

   if (m==1)
   {
      /* Degenerate case where all the twiddles are 1. */
      for (i=0;i<N;i++)
      {
         kiss_fft_cpx scratch0, scratch1;

         C_SUB( scratch0 , *Fout, Fout[2] );
         C_ADDTO(*Fout, Fout[2]);
         C_ADD( scratch1 , Fout[1] , Fout[3] );
         C_SUB( Fout[2], *Fout, scratch1 );
         C_ADDTO( *Fout , scratch1 );
         C_SUB( scratch1 , Fout[1] , Fout[3] );

         Fout[1].r = ADD32_ovflw(scratch0.r, scratch1.i);
         Fout[1].i = SUB32_ovflw(scratch0.i, scratch1.r);
         Fout[3].r = SUB32_ovflw(scratch0.r, scratch1.i);
         Fout[3].i = ADD32_ovflw(scratch0.i, scratch1.r);
         Fout+=4;
      }
   } else {
      int j;
      kiss_fft_cpx scratch[6];
      const kiss_twiddle_cpx *tw1,*tw2,*tw3;
      const int m2=2*m;
      const int m3=3*m;
      kiss_fft_cpx * Fout_beg = Fout;
      for (i=0;i<N;i++)
      {
         Fout = Fout_beg + i*mm;
         tw3 = tw2 = tw1 = st->twiddles;
         /* m is guaranteed to be a multiple of 4. */
         for (j=0;j<m;j++)
         {
            C_MUL(scratch[0],Fout[m] , *tw1 );
            C_MUL(scratch[1],Fout[m2] , *tw2 );
            C_MUL(scratch[2],Fout[m3] , *tw3 );

            C_SUB( scratch[5] , *Fout, scratch[1] );
            C_ADDTO(*Fout, scratch[1]);
            C_ADD( scratch[3] , scratch[0] , scratch[2] );
            C_SUB( scratch[4] , scratch[0] , scratch[2] );
            C_SUB( Fout[m2], *Fout, scratch[3] );
            tw1 += fstride;
            tw2 += fstride*2;
            tw3 += fstride*3;
            C_ADDTO( *Fout , scratch[3] );

            Fout[m].r = ADD32_ovflw(scratch[5].r, scratch[4].i);
            Fout[m].i = SUB32_ovflw(scratch[5].i, scratch[4].r);
            Fout[m3].r = SUB32_ovflw(scratch[5].r, scratch[4].i);
            Fout[m3].i = ADD32_ovflw(scratch[5].i, scratch[4].r);
            ++Fout;
         }
      }
   }
}