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diff --git a/tests/manual/spectrum/3rdparty/fftreal/FFTReal.hpp b/tests/manual/spectrum/3rdparty/fftreal/FFTReal.hpp
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--- a/tests/manual/spectrum/3rdparty/fftreal/FFTReal.hpp
+++ /dev/null
@@ -1,916 +0,0 @@
-/*****************************************************************************
-
- FFTReal.hpp
- Copyright (c) 2005 Laurent de Soras
-
---- Legal stuff ---
-
-This library is free software; you can redistribute it and/or
-modify it under the terms of the GNU Lesser General Public
-License as published by the Free Software Foundation; either
-version 2.1 of the License, or (at your option) any later version.
-
-This library is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-Lesser General Public License for more details.
-
-You should have received a copy of the GNU Lesser General Public
-License along with this library; if not, write to the Free Software
-Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-
-*Tab=3***********************************************************************/
-
-
-
-#if defined (FFTReal_CURRENT_CODEHEADER)
- #error Recursive inclusion of FFTReal code header.
-#endif
-#define FFTReal_CURRENT_CODEHEADER
-
-#if ! defined (FFTReal_CODEHEADER_INCLUDED)
-#define FFTReal_CODEHEADER_INCLUDED
-
-
-
-/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
-
-#include <cassert>
-#include <cmath>
-
-
-
-static inline bool FFTReal_is_pow2 (long x)
-{
- assert (x > 0);
-
- return ((x & -x) == x);
-}
-
-
-
-static inline int FFTReal_get_next_pow2 (long x)
-{
- --x;
-
- int p = 0;
- while ((x & ~0xFFFFL) != 0)
- {
- p += 16;
- x >>= 16;
- }
- while ((x & ~0xFL) != 0)
- {
- p += 4;
- x >>= 4;
- }
- while (x > 0)
- {
- ++p;
- x >>= 1;
- }
-
- return (p);
-}
-
-
-
-/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
-
-
-
-/*
-==============================================================================
-Name: ctor
-Input parameters:
- - length: length of the array on which we want to do a FFT. Range: power of
- 2 only, > 0.
-Throws: std::bad_alloc
-==============================================================================
-*/
-
-template <class DT>
-FFTReal <DT>::FFTReal (long length)
-: _length (length)
-, _nbr_bits (FFTReal_get_next_pow2 (length))
-, _br_lut ()
-, _trigo_lut ()
-, _buffer (length)
-, _trigo_osc ()
-{
- assert (FFTReal_is_pow2 (length));
- assert (_nbr_bits <= MAX_BIT_DEPTH);
-
- init_br_lut ();
- init_trigo_lut ();
- init_trigo_osc ();
-}
-
-
-
-/*
-==============================================================================
-Name: get_length
-Description:
- Returns the number of points processed by this FFT object.
-Returns: The number of points, power of 2, > 0.
-Throws: Nothing
-==============================================================================
-*/
-
-template <class DT>
-long FFTReal <DT>::get_length () const
-{
- return (_length);
-}
-
-
-
-/*
-==============================================================================
-Name: do_fft
-Description:
- Compute the FFT of the array.
-Input parameters:
- - x: pointer on the source array (time).
-Output parameters:
- - f: pointer on the destination array (frequencies).
- f [0...length(x)/2] = real values,
- f [length(x)/2+1...length(x)-1] = negative imaginary values of
- coefficents 1...length(x)/2-1.
-Throws: Nothing
-==============================================================================
-*/
-
-template <class DT>
-void FFTReal <DT>::do_fft (DataType f [], const DataType x []) const
-{
- assert (f != 0);
- assert (f != use_buffer ());
- assert (x != 0);
- assert (x != use_buffer ());
- assert (x != f);
-
- // General case
- if (_nbr_bits > 2)
- {
- compute_fft_general (f, x);
- }
-
- // 4-point FFT
- else if (_nbr_bits == 2)
- {
- f [1] = x [0] - x [2];
- f [3] = x [1] - x [3];
-
- const DataType b_0 = x [0] + x [2];
- const DataType b_2 = x [1] + x [3];
-
- f [0] = b_0 + b_2;
- f [2] = b_0 - b_2;
- }
-
- // 2-point FFT
- else if (_nbr_bits == 1)
- {
- f [0] = x [0] + x [1];
- f [1] = x [0] - x [1];
- }
-
- // 1-point FFT
- else
- {
- f [0] = x [0];
- }
-}
-
-
-
-/*
-==============================================================================
-Name: do_ifft
-Description:
- Compute the inverse FFT of the array. Note that data must be post-scaled:
- IFFT (FFT (x)) = x * length (x).
-Input parameters:
- - f: pointer on the source array (frequencies).
- f [0...length(x)/2] = real values
- f [length(x)/2+1...length(x)-1] = negative imaginary values of
- coefficents 1...length(x)/2-1.
-Output parameters:
- - x: pointer on the destination array (time).
-Throws: Nothing
-==============================================================================
-*/
-
-template <class DT>
-void FFTReal <DT>::do_ifft (const DataType f [], DataType x []) const
-{
- assert (f != 0);
- assert (f != use_buffer ());
- assert (x != 0);
- assert (x != use_buffer ());
- assert (x != f);
-
- // General case
- if (_nbr_bits > 2)
- {
- compute_ifft_general (f, x);
- }
-
- // 4-point IFFT
- else if (_nbr_bits == 2)
- {
- const DataType b_0 = f [0] + f [2];
- const DataType b_2 = f [0] - f [2];
-
- x [0] = b_0 + f [1] * 2;
- x [2] = b_0 - f [1] * 2;
- x [1] = b_2 + f [3] * 2;
- x [3] = b_2 - f [3] * 2;
- }
-
- // 2-point IFFT
- else if (_nbr_bits == 1)
- {
- x [0] = f [0] + f [1];
- x [1] = f [0] - f [1];
- }
-
- // 1-point IFFT
- else
- {
- x [0] = f [0];
- }
-}
-
-
-
-/*
-==============================================================================
-Name: rescale
-Description:
- Scale an array by divide each element by its length. This function should
- be called after FFT + IFFT.
-Input parameters:
- - x: pointer on array to rescale (time or frequency).
-Throws: Nothing
-==============================================================================
-*/
-
-template <class DT>
-void FFTReal <DT>::rescale (DataType x []) const
-{
- const DataType mul = DataType (1.0 / _length);
-
- if (_length < 4)
- {
- long i = _length - 1;
- do
- {
- x [i] *= mul;
- --i;
- }
- while (i >= 0);
- }
-
- else
- {
- assert ((_length & 3) == 0);
-
- // Could be optimized with SIMD instruction sets (needs alignment check)
- long i = _length - 4;
- do
- {
- x [i + 0] *= mul;
- x [i + 1] *= mul;
- x [i + 2] *= mul;
- x [i + 3] *= mul;
- i -= 4;
- }
- while (i >= 0);
- }
-}
-
-
-
-/*
-==============================================================================
-Name: use_buffer
-Description:
- Access the internal buffer, whose length is the FFT one.
- Buffer content will be erased at each do_fft() / do_ifft() call!
- This buffer cannot be used as:
- - source for FFT or IFFT done with this object
- - destination for FFT or IFFT done with this object
-Returns:
- Buffer start address
-Throws: Nothing
-==============================================================================
-*/
-
-template <class DT>
-typename FFTReal <DT>::DataType * FFTReal <DT>::use_buffer () const
-{
- return (&_buffer [0]);
-}
-
-
-
-/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
-
-
-
-/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
-
-
-
-template <class DT>
-void FFTReal <DT>::init_br_lut ()
-{
- const long length = 1L << _nbr_bits;
- _br_lut.resize (length);
-
- _br_lut [0] = 0;
- long br_index = 0;
- for (long cnt = 1; cnt < length; ++cnt)
- {
- // ++br_index (bit reversed)
- long bit = length >> 1;
- while (((br_index ^= bit) & bit) == 0)
- {
- bit >>= 1;
- }
-
- _br_lut [cnt] = br_index;
- }
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::init_trigo_lut ()
-{
- using namespace std;
-
- if (_nbr_bits > 3)
- {
- const long total_len = (1L << (_nbr_bits - 1)) - 4;
- _trigo_lut.resize (total_len);
-
- for (int level = 3; level < _nbr_bits; ++level)
- {
- const long level_len = 1L << (level - 1);
- DataType * const level_ptr =
- &_trigo_lut [get_trigo_level_index (level)];
- const double mul = PI / (level_len << 1);
-
- for (long i = 0; i < level_len; ++ i)
- {
- level_ptr [i] = static_cast <DataType> (cos (i * mul));
- }
- }
- }
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::init_trigo_osc ()
-{
- const int nbr_osc = _nbr_bits - TRIGO_BD_LIMIT;
- if (nbr_osc > 0)
- {
- _trigo_osc.resize (nbr_osc);
-
- for (int osc_cnt = 0; osc_cnt < nbr_osc; ++osc_cnt)
- {
- OscType & osc = _trigo_osc [osc_cnt];
-
- const long len = 1L << (TRIGO_BD_LIMIT + osc_cnt);
- const double mul = (0.5 * PI) / len;
- osc.set_step (mul);
- }
- }
-}
-
-
-
-template <class DT>
-const long * FFTReal <DT>::get_br_ptr () const
-{
- return (&_br_lut [0]);
-}
-
-
-
-template <class DT>
-const typename FFTReal <DT>::DataType * FFTReal <DT>::get_trigo_ptr (int level) const
-{
- assert (level >= 3);
-
- return (&_trigo_lut [get_trigo_level_index (level)]);
-}
-
-
-
-template <class DT>
-long FFTReal <DT>::get_trigo_level_index (int level) const
-{
- assert (level >= 3);
-
- return ((1L << (level - 1)) - 4);
-}
-
-
-
-// Transform in several passes
-template <class DT>
-void FFTReal <DT>::compute_fft_general (DataType f [], const DataType x []) const
-{
- assert (f != 0);
- assert (f != use_buffer ());
- assert (x != 0);
- assert (x != use_buffer ());
- assert (x != f);
-
- DataType * sf;
- DataType * df;
-
- if ((_nbr_bits & 1) != 0)
- {
- df = use_buffer ();
- sf = f;
- }
- else
- {
- df = f;
- sf = use_buffer ();
- }
-
- compute_direct_pass_1_2 (df, x);
- compute_direct_pass_3 (sf, df);
-
- for (int pass = 3; pass < _nbr_bits; ++ pass)
- {
- compute_direct_pass_n (df, sf, pass);
-
- DataType * const temp_ptr = df;
- df = sf;
- sf = temp_ptr;
- }
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_direct_pass_1_2 (DataType df [], const DataType x []) const
-{
- assert (df != 0);
- assert (x != 0);
- assert (df != x);
-
- const long * const bit_rev_lut_ptr = get_br_ptr ();
- long coef_index = 0;
- do
- {
- const long rev_index_0 = bit_rev_lut_ptr [coef_index];
- const long rev_index_1 = bit_rev_lut_ptr [coef_index + 1];
- const long rev_index_2 = bit_rev_lut_ptr [coef_index + 2];
- const long rev_index_3 = bit_rev_lut_ptr [coef_index + 3];
-
- DataType * const df2 = df + coef_index;
- df2 [1] = x [rev_index_0] - x [rev_index_1];
- df2 [3] = x [rev_index_2] - x [rev_index_3];
-
- const DataType sf_0 = x [rev_index_0] + x [rev_index_1];
- const DataType sf_2 = x [rev_index_2] + x [rev_index_3];
-
- df2 [0] = sf_0 + sf_2;
- df2 [2] = sf_0 - sf_2;
-
- coef_index += 4;
- }
- while (coef_index < _length);
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_direct_pass_3 (DataType df [], const DataType sf []) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
-
- const DataType sqrt2_2 = DataType (SQRT2 * 0.5);
- long coef_index = 0;
- do
- {
- DataType v;
-
- df [coef_index] = sf [coef_index] + sf [coef_index + 4];
- df [coef_index + 4] = sf [coef_index] - sf [coef_index + 4];
- df [coef_index + 2] = sf [coef_index + 2];
- df [coef_index + 6] = sf [coef_index + 6];
-
- v = (sf [coef_index + 5] - sf [coef_index + 7]) * sqrt2_2;
- df [coef_index + 1] = sf [coef_index + 1] + v;
- df [coef_index + 3] = sf [coef_index + 1] - v;
-
- v = (sf [coef_index + 5] + sf [coef_index + 7]) * sqrt2_2;
- df [coef_index + 5] = v + sf [coef_index + 3];
- df [coef_index + 7] = v - sf [coef_index + 3];
-
- coef_index += 8;
- }
- while (coef_index < _length);
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_direct_pass_n (DataType df [], const DataType sf [], int pass) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
- assert (pass >= 3);
- assert (pass < _nbr_bits);
-
- if (pass <= TRIGO_BD_LIMIT)
- {
- compute_direct_pass_n_lut (df, sf, pass);
- }
- else
- {
- compute_direct_pass_n_osc (df, sf, pass);
- }
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_direct_pass_n_lut (DataType df [], const DataType sf [], int pass) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
- assert (pass >= 3);
- assert (pass < _nbr_bits);
-
- const long nbr_coef = 1 << pass;
- const long h_nbr_coef = nbr_coef >> 1;
- const long d_nbr_coef = nbr_coef << 1;
- long coef_index = 0;
- const DataType * const cos_ptr = get_trigo_ptr (pass);
- do
- {
- const DataType * const sf1r = sf + coef_index;
- const DataType * const sf2r = sf1r + nbr_coef;
- DataType * const dfr = df + coef_index;
- DataType * const dfi = dfr + nbr_coef;
-
- // Extreme coefficients are always real
- dfr [0] = sf1r [0] + sf2r [0];
- dfi [0] = sf1r [0] - sf2r [0]; // dfr [nbr_coef] =
- dfr [h_nbr_coef] = sf1r [h_nbr_coef];
- dfi [h_nbr_coef] = sf2r [h_nbr_coef];
-
- // Others are conjugate complex numbers
- const DataType * const sf1i = sf1r + h_nbr_coef;
- const DataType * const sf2i = sf1i + nbr_coef;
- for (long i = 1; i < h_nbr_coef; ++ i)
- {
- const DataType c = cos_ptr [i]; // cos (i*PI/nbr_coef);
- const DataType s = cos_ptr [h_nbr_coef - i]; // sin (i*PI/nbr_coef);
- DataType v;
-
- v = sf2r [i] * c - sf2i [i] * s;
- dfr [i] = sf1r [i] + v;
- dfi [-i] = sf1r [i] - v; // dfr [nbr_coef - i] =
-
- v = sf2r [i] * s + sf2i [i] * c;
- dfi [i] = v + sf1i [i];
- dfi [nbr_coef - i] = v - sf1i [i];
- }
-
- coef_index += d_nbr_coef;
- }
- while (coef_index < _length);
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_direct_pass_n_osc (DataType df [], const DataType sf [], int pass) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
- assert (pass > TRIGO_BD_LIMIT);
- assert (pass < _nbr_bits);
-
- const long nbr_coef = 1 << pass;
- const long h_nbr_coef = nbr_coef >> 1;
- const long d_nbr_coef = nbr_coef << 1;
- long coef_index = 0;
- OscType & osc = _trigo_osc [pass - (TRIGO_BD_LIMIT + 1)];
- do
- {
- const DataType * const sf1r = sf + coef_index;
- const DataType * const sf2r = sf1r + nbr_coef;
- DataType * const dfr = df + coef_index;
- DataType * const dfi = dfr + nbr_coef;
-
- osc.clear_buffers ();
-
- // Extreme coefficients are always real
- dfr [0] = sf1r [0] + sf2r [0];
- dfi [0] = sf1r [0] - sf2r [0]; // dfr [nbr_coef] =
- dfr [h_nbr_coef] = sf1r [h_nbr_coef];
- dfi [h_nbr_coef] = sf2r [h_nbr_coef];
-
- // Others are conjugate complex numbers
- const DataType * const sf1i = sf1r + h_nbr_coef;
- const DataType * const sf2i = sf1i + nbr_coef;
- for (long i = 1; i < h_nbr_coef; ++ i)
- {
- osc.step ();
- const DataType c = osc.get_cos ();
- const DataType s = osc.get_sin ();
- DataType v;
-
- v = sf2r [i] * c - sf2i [i] * s;
- dfr [i] = sf1r [i] + v;
- dfi [-i] = sf1r [i] - v; // dfr [nbr_coef - i] =
-
- v = sf2r [i] * s + sf2i [i] * c;
- dfi [i] = v + sf1i [i];
- dfi [nbr_coef - i] = v - sf1i [i];
- }
-
- coef_index += d_nbr_coef;
- }
- while (coef_index < _length);
-}
-
-
-
-// Transform in several pass
-template <class DT>
-void FFTReal <DT>::compute_ifft_general (const DataType f [], DataType x []) const
-{
- assert (f != 0);
- assert (f != use_buffer ());
- assert (x != 0);
- assert (x != use_buffer ());
- assert (x != f);
-
- DataType * sf = const_cast <DataType *> (f);
- DataType * df;
- DataType * df_temp;
-
- if (_nbr_bits & 1)
- {
- df = use_buffer ();
- df_temp = x;
- }
- else
- {
- df = x;
- df_temp = use_buffer ();
- }
-
- for (int pass = _nbr_bits - 1; pass >= 3; -- pass)
- {
- compute_inverse_pass_n (df, sf, pass);
-
- if (pass < _nbr_bits - 1)
- {
- DataType * const temp_ptr = df;
- df = sf;
- sf = temp_ptr;
- }
- else
- {
- sf = df;
- df = df_temp;
- }
- }
-
- compute_inverse_pass_3 (df, sf);
- compute_inverse_pass_1_2 (x, df);
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_inverse_pass_n (DataType df [], const DataType sf [], int pass) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
- assert (pass >= 3);
- assert (pass < _nbr_bits);
-
- if (pass <= TRIGO_BD_LIMIT)
- {
- compute_inverse_pass_n_lut (df, sf, pass);
- }
- else
- {
- compute_inverse_pass_n_osc (df, sf, pass);
- }
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_inverse_pass_n_lut (DataType df [], const DataType sf [], int pass) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
- assert (pass >= 3);
- assert (pass < _nbr_bits);
-
- const long nbr_coef = 1 << pass;
- const long h_nbr_coef = nbr_coef >> 1;
- const long d_nbr_coef = nbr_coef << 1;
- long coef_index = 0;
- const DataType * const cos_ptr = get_trigo_ptr (pass);
- do
- {
- const DataType * const sfr = sf + coef_index;
- const DataType * const sfi = sfr + nbr_coef;
- DataType * const df1r = df + coef_index;
- DataType * const df2r = df1r + nbr_coef;
-
- // Extreme coefficients are always real
- df1r [0] = sfr [0] + sfi [0]; // + sfr [nbr_coef]
- df2r [0] = sfr [0] - sfi [0]; // - sfr [nbr_coef]
- df1r [h_nbr_coef] = sfr [h_nbr_coef] * 2;
- df2r [h_nbr_coef] = sfi [h_nbr_coef] * 2;
-
- // Others are conjugate complex numbers
- DataType * const df1i = df1r + h_nbr_coef;
- DataType * const df2i = df1i + nbr_coef;
- for (long i = 1; i < h_nbr_coef; ++ i)
- {
- df1r [i] = sfr [i] + sfi [-i]; // + sfr [nbr_coef - i]
- df1i [i] = sfi [i] - sfi [nbr_coef - i];
-
- const DataType c = cos_ptr [i]; // cos (i*PI/nbr_coef);
- const DataType s = cos_ptr [h_nbr_coef - i]; // sin (i*PI/nbr_coef);
- const DataType vr = sfr [i] - sfi [-i]; // - sfr [nbr_coef - i]
- const DataType vi = sfi [i] + sfi [nbr_coef - i];
-
- df2r [i] = vr * c + vi * s;
- df2i [i] = vi * c - vr * s;
- }
-
- coef_index += d_nbr_coef;
- }
- while (coef_index < _length);
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_inverse_pass_n_osc (DataType df [], const DataType sf [], int pass) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
- assert (pass > TRIGO_BD_LIMIT);
- assert (pass < _nbr_bits);
-
- const long nbr_coef = 1 << pass;
- const long h_nbr_coef = nbr_coef >> 1;
- const long d_nbr_coef = nbr_coef << 1;
- long coef_index = 0;
- OscType & osc = _trigo_osc [pass - (TRIGO_BD_LIMIT + 1)];
- do
- {
- const DataType * const sfr = sf + coef_index;
- const DataType * const sfi = sfr + nbr_coef;
- DataType * const df1r = df + coef_index;
- DataType * const df2r = df1r + nbr_coef;
-
- osc.clear_buffers ();
-
- // Extreme coefficients are always real
- df1r [0] = sfr [0] + sfi [0]; // + sfr [nbr_coef]
- df2r [0] = sfr [0] - sfi [0]; // - sfr [nbr_coef]
- df1r [h_nbr_coef] = sfr [h_nbr_coef] * 2;
- df2r [h_nbr_coef] = sfi [h_nbr_coef] * 2;
-
- // Others are conjugate complex numbers
- DataType * const df1i = df1r + h_nbr_coef;
- DataType * const df2i = df1i + nbr_coef;
- for (long i = 1; i < h_nbr_coef; ++ i)
- {
- df1r [i] = sfr [i] + sfi [-i]; // + sfr [nbr_coef - i]
- df1i [i] = sfi [i] - sfi [nbr_coef - i];
-
- osc.step ();
- const DataType c = osc.get_cos ();
- const DataType s = osc.get_sin ();
- const DataType vr = sfr [i] - sfi [-i]; // - sfr [nbr_coef - i]
- const DataType vi = sfi [i] + sfi [nbr_coef - i];
-
- df2r [i] = vr * c + vi * s;
- df2i [i] = vi * c - vr * s;
- }
-
- coef_index += d_nbr_coef;
- }
- while (coef_index < _length);
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_inverse_pass_3 (DataType df [], const DataType sf []) const
-{
- assert (df != 0);
- assert (sf != 0);
- assert (df != sf);
-
- const DataType sqrt2_2 = DataType (SQRT2 * 0.5);
- long coef_index = 0;
- do
- {
- df [coef_index] = sf [coef_index] + sf [coef_index + 4];
- df [coef_index + 4] = sf [coef_index] - sf [coef_index + 4];
- df [coef_index + 2] = sf [coef_index + 2] * 2;
- df [coef_index + 6] = sf [coef_index + 6] * 2;
-
- df [coef_index + 1] = sf [coef_index + 1] + sf [coef_index + 3];
- df [coef_index + 3] = sf [coef_index + 5] - sf [coef_index + 7];
-
- const DataType vr = sf [coef_index + 1] - sf [coef_index + 3];
- const DataType vi = sf [coef_index + 5] + sf [coef_index + 7];
-
- df [coef_index + 5] = (vr + vi) * sqrt2_2;
- df [coef_index + 7] = (vi - vr) * sqrt2_2;
-
- coef_index += 8;
- }
- while (coef_index < _length);
-}
-
-
-
-template <class DT>
-void FFTReal <DT>::compute_inverse_pass_1_2 (DataType x [], const DataType sf []) const
-{
- assert (x != 0);
- assert (sf != 0);
- assert (x != sf);
-
- const long * bit_rev_lut_ptr = get_br_ptr ();
- const DataType * sf2 = sf;
- long coef_index = 0;
- do
- {
- {
- const DataType b_0 = sf2 [0] + sf2 [2];
- const DataType b_2 = sf2 [0] - sf2 [2];
- const DataType b_1 = sf2 [1] * 2;
- const DataType b_3 = sf2 [3] * 2;
-
- x [bit_rev_lut_ptr [0]] = b_0 + b_1;
- x [bit_rev_lut_ptr [1]] = b_0 - b_1;
- x [bit_rev_lut_ptr [2]] = b_2 + b_3;
- x [bit_rev_lut_ptr [3]] = b_2 - b_3;
- }
- {
- const DataType b_0 = sf2 [4] + sf2 [6];
- const DataType b_2 = sf2 [4] - sf2 [6];
- const DataType b_1 = sf2 [5] * 2;
- const DataType b_3 = sf2 [7] * 2;
-
- x [bit_rev_lut_ptr [4]] = b_0 + b_1;
- x [bit_rev_lut_ptr [5]] = b_0 - b_1;
- x [bit_rev_lut_ptr [6]] = b_2 + b_3;
- x [bit_rev_lut_ptr [7]] = b_2 - b_3;
- }
-
- sf2 += 8;
- coef_index += 8;
- bit_rev_lut_ptr += 8;
- }
- while (coef_index < _length);
-}
-
-
-
-#endif // FFTReal_CODEHEADER_INCLUDED
-
-#undef FFTReal_CURRENT_CODEHEADER
-
-
-
-/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
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