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diff --git a/src/minphase_hrtfcont.cpp b/src/minphase_hrtfcont.cpp
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+/*
+    cw_binaural~: a binaural synthesis external for pure data
+    by David Doukhan - david.doukhan@gmail.com - http://www.limsi.fr/Individu/doukhan
+    and Anne Sedes - sedes.anne@gmail.com
+    Copyright (C) 2009-2011  David Doukhan and Anne Sedes
+
+    For more details, see CW_binaural~, a binaural synthesis external for Pure Data
+    David Doukhan and Anne Sedes, PDCON09
+
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program 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 General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+
+#include <math.h>
+#include <m_pd.h> //needed for fft implementation
+#include "minphase_hrtfcont.hpp"
+#include "flyweight_ir_factory.hpp"
+
+MinPhaseHrtfCont::MinPhaseHrtfCont(const ir_key&k):
+  HrtfCont(k)
+{
+  ir_key	k2 = k;
+
+  // set impulse response length
+  _ir_length = k.length;
+  // FIXME: IR size verification ??? => power of 2
+
+  // get the container storing the coresponding temporal impulse response
+  k2.minp_ap_dec = false;
+  HrtfCont* hc = FlyweightIrFactory::instance()->hrtf_set_get(k2);
+  
+  // iterate on the container storing the temporal impulse response
+  for (angle1_cit ie = hc->map_get()->begin(); ie != hc->map_get()->end(); ie++)
+    for (angle2_cit ia2 = ie->second.begin(); ia2 != ie->second.end(); ia2++)
+      {
+	// current azimuth and elevation
+	const float el = ie->first;
+	const float az = ia2->first;
+
+	// allocate buffers
+	float *lbuf = _m[el][az].lbuf = new float[_ir_length];
+	float *rbuf = _m[el][az].rbuf = new float[_ir_length];
+	
+	minphase_ir(ia2->second.lbuf, lbuf, _ir_length);
+	minphase_ir(ia2->second.rbuf, rbuf, _ir_length);
+      }
+}
+
+// store in dst the magnitude of spectrum src of size n
+// assumption: src is the specetrum of a real signal
+void MinPhaseHrtfCont::magnitude(const float* src, float* dst, size_t n)
+{
+  for (size_t i = 1; i < n/2; ++i)
+    {
+      dst[i] = sqrt(src[i]*src[i] + src[n-i] * src[n-i]);
+      dst[n -i] = dst[i];
+    }
+  dst[0] = src[0] >= 0 ? src[0] : -src[0];
+  dst[n/2] = src[n/2] >= 0 ? src[n/2] : -src[n/2];
+}
+
+// store in dst the imaginary part of hilbert transform
+// applied to signal src of size n
+void MinPhaseHrtfCont::im_hilbert(const float* src, float* dst, size_t n)
+{
+  size_t i;
+  float tmp;
+  
+  if (dst != src)
+    for (i = 0; i < n; ++i)
+      dst[i] = src[i];
+  
+  mayer_realfft(n, dst);
+  
+  for (i = 1; i < n/2; ++i)
+    {
+      tmp = dst[i];
+      dst[i] = -dst[n -i];
+      dst[n-i] = tmp;
+    }
+  dst[0] = dst[n/2] = 0;
+  
+  mayer_realifft(n, dst);
+  
+  for (i = 0; i < n; ++i)
+    dst[i] /= n;
+}
+
+// store in dst the minphase impulse response corresponding to src
+void MinPhaseHrtfCont::minphase_ir(const float* src, float* dst, int n)
+{
+  float *sig_spectrum = new float[n];
+  float *magn, *phase;
+  int i;
+  
+  // compute the spectrum from input signal
+  for (i = 0; i < n; ++i)
+    sig_spectrum[i] = src[i];
+  mayer_realfft(n, sig_spectrum);
+  
+  // get the magnitude of the spectrum => symetric signal
+  magn = new float[n];
+  magnitude(sig_spectrum, magn, n);
+  
+  // compute hilbert transform of the log of the magnitude
+  // this computation correspond to the minimum phase
+  phase = new float[n];
+  for (i = 0; i < n; ++i)
+    phase[i] = -log(magn[i]);
+  im_hilbert(phase, phase, n);
+   
+  float* real = new float[n];
+  float* imag = new float[n];
+  
+  for (i = 0; i < n; ++i)
+    {
+      real[i] = magn[i] * cos(phase[i]);
+      imag[i] = magn[i] * sin(phase[i]);
+    }
+  mayer_ifft(n, real, imag);
+  
+  delete [] sig_spectrum;
+  delete [] imag;
+  delete [] magn;
+  delete [] phase;
+
+  for (i = 0; i < n; ++i)
+    dst[i] = real[i] /= n;
+  delete [] real;
+}