AudioWindowing.cxx

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00001 /*
00002  * Copyright (c) 2001-2004 MUSIC TECHNOLOGY GROUP (MTG)
00003  *                         UNIVERSITAT POMPEU FABRA
00004  *
00005  *
00006  * This program is free software; you can redistribute it and/or modify
00007  * it under the terms of the GNU General Public License as published by
00008  * the Free Software Foundation; either version 2 of the License, or
00009  * (at your option) any later version.
00010  *
00011  * This program is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014  * GNU General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU General Public License
00017  * along with this program; if not, write to the Free Software
00018  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
00019  *
00020  */
00021 
00022 #include "Segment.hxx"
00023 #include "Frame.hxx"
00024 #include "SpectrumConfig.hxx"
00025 #include "AudioWindowing.hxx"
00026 #include "ProcessingFactory.hxx"
00027 
00028 namespace CLAM
00029 {
00030 
00031 namespace Hidden 
00032 {
00033         static const char* metadata[] = {
00034                 "key", "AudioWindowing",
00035                 "category", "Analysis",
00036                 "description", "AudioWindowing",
00037                 0
00038         };
00039         static FactoryRegistrator<ProcessingFactory, AudioWindowing> reg = metadata;
00040 }
00041 
00042 AudioWindowing::~AudioWindowing()
00043 {
00044 }
00045 
00046 bool AudioWindowing::ConcreteConfigure(const ProcessingConfig& cfg)
00047 {
00048         CopyAsConcreteConfig(mConfig,cfg);
00049  
00050         if (! ConfigureChildren()) return false;
00051         ConfigureData();
00052         return true;
00053 }
00054 
00055 bool AudioWindowing::ConfigureChildren()
00056 {
00057         int windowSize = mConfig.GetWindowSize();
00058         EWindowType windowType = mConfig.GetWindowType();
00059         if (not (windowSize&1))
00060         {
00061                 AddConfigErrorMessage("FFT Restriction:");
00062                 AddConfigErrorMessage("Window size should be odd.");
00063                 return false;
00064         }
00065         // TODO: Review those restriction
00066         /*
00067         if (windowSize<2*hopSize+1)
00068         {
00069                 AddConfigErrorMessage("FFT Restriction:");
00070                 AddConfigErrorMessage("This condition is not met: WindowSize < 2*HopSize+1");
00071                 return false;
00072         }
00073         */
00074         if (not isPowerOfTwo(mConfig.GetFFTSize()))
00075         {
00076                 AddConfigErrorMessage("FFT Restriction:");
00077                 AddConfigErrorMessage("FFT Size should be a power of two.");
00078                 return false;
00079         }
00080         WindowGeneratorConfig windowGeneratorConfig;
00081         windowGeneratorConfig.SetSize(windowSize);
00082         windowGeneratorConfig.SetType(windowType);
00083         if (! mWindowGenerator.Configure(windowGeneratorConfig) )
00084         {
00085                 AddConfigErrorMessage("Window Generator configuration failed.");
00086                 AddConfigErrorMessage(mWindowGenerator.GetConfigErrorMessage());
00087                 return false;
00088         }
00089 
00090         CircularShiftConfig circularShiftConfig;
00091         circularShiftConfig.SetAmount(-((windowSize-1)/TData(2))); 
00092         if (! mCircularShift.Configure(circularShiftConfig) )
00093         {
00094                 AddConfigErrorMessage("Circular Shift configuration failed.");
00095                 AddConfigErrorMessage(mCircularShift.GetConfigErrorMessage());
00096                 return false;
00097         }
00098 
00099         return true;
00100 }
00101 
00102 void AudioWindowing::ConfigureData()
00103 {
00104         mInput.SetSize(mConfig.GetWindowSize()-1);
00105         mInput.SetHop(mConfig.GetHopSize());
00106 
00107         mWindow.SetSize(mConfig.GetWindowSize());
00108         
00109         /*Window is generated and data is kept in internal member mWindow*/
00110         mWindowGenerator.Do(mWindow);
00111         
00112         /*Leaving out last sample of odd-sized window*/
00113         mWindow.SetSize(mWindow.GetSize()-1);
00114 
00115         /* Adding zero padding to windowing function */
00116         mWindow.SetSize(mConfig.GetFFTSize());
00117 }
00118 
00119 void AudioWindowing::AttachChildren()
00120 {
00121         mWindowGenerator.SetParent(this);
00122         mAudioProduct.SetParent(this);
00123         mCircularShift.SetParent(this);
00124 }
00125 
00126 bool AudioWindowing::Do(void)
00127 {
00128         bool result =  Do(mInput.GetAudio(),mOutput.GetData());
00129 
00130         mInput.Consume();
00131         mOutput.Produce();
00132 
00133         return result;
00134 }
00135 
00136 bool AudioWindowing::Do(const Audio& in,Audio& out)
00137 {
00138         in.GetAudioChunk(0,in.GetSize() ,out,true );
00139         out.SetSampleRate(mConfig.GetSamplingRate());
00140 
00141         // Zero padding
00142         out.SetSize(mConfig.GetFFTSize());
00143         
00144         // Windowing
00145         if (mConfig.GetWindowType()!=EWindowType::eNone )
00146                 mAudioProduct.Do(out, mWindow, out);
00147         
00148         // Half Window Shift
00149         if (mConfig.GetDoHalfWindowShift())
00150                 mCircularShift.Do(out,out);
00151 
00152 
00153         return true;
00154 }
00155 
00156 
00157 
00158 } // namespace CLAM
00159 
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