Marsyas  0.6.0-alpha
/usr/src/RPM/BUILD/marsyas-0.6.0/src/marsyas/marsystems/SpectralFlatnessAllBands.cpp
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00001 /*
00002 ** Copyright (C) 1998-2010 George Tzanetakis <gtzan@cs.uvic.ca>
00003 **
00004 ** This program is free software; you can redistribute it and/or modify
00005 ** it under the terms of the GNU General Public License as published by
00006 ** the Free Software Foundation; either version 2 of the License, or
00007 ** (at your option) any later version.
00008 **
00009 ** This program is distributed in the hope that it will be useful,
00010 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
00011 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00012 ** GNU General Public License for more details.
00013 **
00014 ** You should have received a copy of the GNU General Public License
00015 ** along with this program; if not, write to the Free Software
00016 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
00017 */
00018 
00019 #include "../common_source.h"
00020 #include "SpectralFlatnessAllBands.h"
00021 
00022 using std::ostringstream;
00023 using namespace Marsyas;
00024 
00025 SpectralFlatnessAllBands::SpectralFlatnessAllBands(mrs_string name) : MarSystem("SpectralFlatnessAllBands", name)
00026 {
00028   addControls();
00029 }
00030 
00031 SpectralFlatnessAllBands::SpectralFlatnessAllBands(const SpectralFlatnessAllBands& a) : MarSystem(a)
00032 {
00033 }
00034 
00035 
00036 SpectralFlatnessAllBands::~SpectralFlatnessAllBands()
00037 {
00038 }
00039 
00040 MarSystem*
00041 SpectralFlatnessAllBands::clone() const
00042 {
00043   return new SpectralFlatnessAllBands(*this);
00044 }
00045 
00046 void
00047 SpectralFlatnessAllBands::addControls()
00048 {
00049 }
00050 
00051 void
00052 SpectralFlatnessAllBands::myUpdate(MarControlPtr sender)
00053 {
00054   MRSDIAG("SpectralFlatnessAllBands.cpp - SpectralFlatnessAllBands:myUpdate");
00055 
00057   MarSystem::myUpdate(sender);
00058 
00059   // overwrite default settings as needed
00060   ctrl_onObservations_->setValue((mrs_natural)1, NOUPDATE);
00061 
00062   // Add prefix to the observation names.
00063   mrs_string inObsNames = ctrl_inObsNames_->to<mrs_string>();
00064   ctrl_onObsNames_->setValue(obsNamesAddPrefix(inObsNames,
00065                              "SpectralFlatnessAllBands_"), NOUPDATE);
00066 
00067 }
00068 
00069 void
00070 SpectralFlatnessAllBands::myProcess(realvec& in, realvec& out)
00071 {
00072   mrs_natural t,o;
00073 
00074   // swap Observations_ and Samples_ because it's intended
00075   // for spectral!
00076 
00077   for (t = 0; t < inSamples_; t++)
00078   {
00079     // we use log scale to calculate the geometric
00080     // mean, to avoid going lower than E-308, which is
00081     // the lower limit for doubles in C++.
00082     mrs_real geometric_mean = 0.0; // in log scale
00083     mrs_real arithmetic_mean = 0.0;
00084     for (o = 0; o < inObservations_; o++)
00085     {
00086       geometric_mean += log( in(o,t) ); // in log scale
00087       arithmetic_mean += in(o,t);
00088     }
00089     if (inObservations_ > 0) {
00090       geometric_mean /= inObservations_; // in log scale
00091       arithmetic_mean /= inObservations_;
00092     }
00093     geometric_mean = exp( geometric_mean ); // no more log scale
00094     if (arithmetic_mean > 0) {
00095       out(0, t) = geometric_mean / arithmetic_mean;
00096     } else {
00097       // treat complete silence as white noise
00098       out(0, t) = 1.0;
00099     }
00100   }
00101 
00102 }