--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/demos/spectrum/3rdparty/fftreal/FFTRealPassInverse.hpp Fri Jun 11 14:24:45 2010 +0300
@@ -0,0 +1,229 @@
+/*****************************************************************************
+
+ FFTRealPassInverse.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 (FFTRealPassInverse_CURRENT_CODEHEADER)
+ #error Recursive inclusion of FFTRealPassInverse code header.
+#endif
+#define FFTRealPassInverse_CURRENT_CODEHEADER
+
+#if ! defined (FFTRealPassInverse_CODEHEADER_INCLUDED)
+#define FFTRealPassInverse_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include "FFTRealUseTrigo.h"
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <int PASS>
+void FFTRealPassInverse <PASS>::process (long len, DataType dest_ptr [], DataType src_ptr [], const DataType f_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+ process_internal (
+ len,
+ dest_ptr,
+ f_ptr,
+ cos_ptr,
+ cos_len,
+ br_ptr,
+ osc_list
+ );
+ FFTRealPassInverse <PASS - 1>::process_rec (
+ len,
+ src_ptr,
+ dest_ptr,
+ cos_ptr,
+ cos_len,
+ br_ptr,
+ osc_list
+ );
+}
+
+
+
+template <int PASS>
+void FFTRealPassInverse <PASS>::process_rec (long len, DataType dest_ptr [], DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+ process_internal (
+ len,
+ dest_ptr,
+ src_ptr,
+ cos_ptr,
+ cos_len,
+ br_ptr,
+ osc_list
+ );
+ FFTRealPassInverse <PASS - 1>::process_rec (
+ len,
+ src_ptr,
+ dest_ptr,
+ cos_ptr,
+ cos_len,
+ br_ptr,
+ osc_list
+ );
+}
+
+template <>
+void FFTRealPassInverse <0>::process_rec (long len, DataType dest_ptr [], DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+ // Stops recursion
+}
+
+
+
+template <int PASS>
+void FFTRealPassInverse <PASS>::process_internal (long len, DataType dest_ptr [], const DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+ const long dist = 1L << (PASS - 1);
+ const long c1_r = 0;
+ const long c1_i = dist;
+ const long c2_r = dist * 2;
+ const long c2_i = dist * 3;
+ const long cend = dist * 4;
+ const long table_step = cos_len >> (PASS - 1);
+
+ enum { TRIGO_OSC = PASS - FFTRealFixLenParam::TRIGO_BD_LIMIT };
+ enum { TRIGO_DIRECT = (TRIGO_OSC >= 0) ? 1 : 0 };
+
+ long coef_index = 0;
+ do
+ {
+ const DataType * const sf = src_ptr + coef_index;
+ DataType * const df = dest_ptr + coef_index;
+
+ // Extreme coefficients are always real
+ df [c1_r] = sf [c1_r] + sf [c2_r];
+ df [c2_r] = sf [c1_r] - sf [c2_r];
+ df [c1_i] = sf [c1_i] * 2;
+ df [c2_i] = sf [c2_i] * 2;
+
+ FFTRealUseTrigo <TRIGO_DIRECT>::prepare (osc_list [TRIGO_OSC]);
+
+ // Others are conjugate complex numbers
+ for (long i = 1; i < dist; ++ i)
+ {
+ df [c1_r + i] = sf [c1_r + i] + sf [c2_r - i];
+ df [c1_i + i] = sf [c2_r + i] - sf [cend - i];
+
+ DataType c;
+ DataType s;
+ FFTRealUseTrigo <TRIGO_DIRECT>::iterate (
+ osc_list [TRIGO_OSC],
+ c,
+ s,
+ cos_ptr,
+ i * table_step,
+ (dist - i) * table_step
+ );
+
+ const DataType vr = sf [c1_r + i] - sf [c2_r - i];
+ const DataType vi = sf [c2_r + i] + sf [cend - i];
+
+ df [c2_r + i] = vr * c + vi * s;
+ df [c2_i + i] = vi * c - vr * s;
+ }
+
+ coef_index += cend;
+ }
+ while (coef_index < len);
+}
+
+template <>
+void FFTRealPassInverse <2>::process_internal (long len, DataType dest_ptr [], const DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+ // Antepenultimate pass
+ const DataType sqrt2_2 = DataType (SQRT2 * 0.5);
+
+ long coef_index = 0;
+ do
+ {
+ dest_ptr [coef_index ] = src_ptr [coef_index] + src_ptr [coef_index + 4];
+ dest_ptr [coef_index + 4] = src_ptr [coef_index] - src_ptr [coef_index + 4];
+ dest_ptr [coef_index + 2] = src_ptr [coef_index + 2] * 2;
+ dest_ptr [coef_index + 6] = src_ptr [coef_index + 6] * 2;
+
+ dest_ptr [coef_index + 1] = src_ptr [coef_index + 1] + src_ptr [coef_index + 3];
+ dest_ptr [coef_index + 3] = src_ptr [coef_index + 5] - src_ptr [coef_index + 7];
+
+ const DataType vr = src_ptr [coef_index + 1] - src_ptr [coef_index + 3];
+ const DataType vi = src_ptr [coef_index + 5] + src_ptr [coef_index + 7];
+
+ dest_ptr [coef_index + 5] = (vr + vi) * sqrt2_2;
+ dest_ptr [coef_index + 7] = (vi - vr) * sqrt2_2;
+
+ coef_index += 8;
+ }
+ while (coef_index < len);
+}
+
+template <>
+void FFTRealPassInverse <1>::process_internal (long len, DataType dest_ptr [], const DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+ // Penultimate and last pass at once
+ const long qlen = len >> 2;
+
+ long coef_index = 0;
+ do
+ {
+ const long ri_0 = br_ptr [coef_index >> 2];
+
+ const DataType b_0 = src_ptr [coef_index ] + src_ptr [coef_index + 2];
+ const DataType b_2 = src_ptr [coef_index ] - src_ptr [coef_index + 2];
+ const DataType b_1 = src_ptr [coef_index + 1] * 2;
+ const DataType b_3 = src_ptr [coef_index + 3] * 2;
+
+ dest_ptr [ri_0 ] = b_0 + b_1;
+ dest_ptr [ri_0 + 2 * qlen] = b_0 - b_1;
+ dest_ptr [ri_0 + 1 * qlen] = b_2 + b_3;
+ dest_ptr [ri_0 + 3 * qlen] = b_2 - b_3;
+
+ coef_index += 4;
+ }
+ while (coef_index < len);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif // FFTRealPassInverse_CODEHEADER_INCLUDED
+
+#undef FFTRealPassInverse_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/