CLAM-Development  1.4.0
3BandCompressor.cxx
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1 /*
2  * Copyright (c) 2001-2004 MUSIC TECHNOLOGY GROUP (MTG)
3  * UNIVERSITAT POMPEU FABRA
4  *
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19  *
20  */
21 
22 #include "3BandCompressor.hxx"
23 #include "ProcessingFactory.hxx"
24 
25 namespace CLAM
26 {
27 
28 namespace Hidden
29 {
30  static const char * metadata[] = {
31  "key", "ThreeBandCompressor",
32  "category", "Spectral Transformations",
33  "description", "ThreeBandCompressor",
34  0
35  };
36  static FactoryRegistrator<ProcessingFactory, ThreeBandCompressor> reg = metadata;
37 }
38 
40 {
41  out = in; //even if out needs to be preserved, we need to copy content
42 
43  DataArray& oMag = out.GetMagBuffer();
44  const DataArray& iMag = in.GetMagBuffer();
45 
46  int spectrumSize = in.GetSize();
47 
48  TData spectralResolution = spectrumSize/in.GetSpectralRange();
49 
50  int lowCutoff = Round(mLowCutoffFreqCtl.GetLastValue()* spectralResolution);
51  int highCutoff = Round(mHighCutoffFreqCtl.GetLastValue()* spectralResolution);
52 
53  //note: control is supposed to be sent as dB's
54  TData lowThreshold = log2lin(mLowThresholdCtl.GetLastValue());
55  TData midThreshold = log2lin(mMidThresholdCtl.GetLastValue());
56  TData highThreshold = log2lin(mHighThresholdCtl.GetLastValue());
57 
58  TData currentThreshold = lowThreshold;
59  for(int i = 0; i<lowCutoff; i++)
60  {
61  if(iMag[i]>lowThreshold)
62  oMag[i] = lowThreshold;
63  }
64  for(int i = lowCutoff; i<highCutoff; i++)
65  {
66  if(iMag[i]>midThreshold)
67  oMag[i] = midThreshold;
68  }
69  for(int i = highCutoff; i<spectrumSize; i++)
70  {
71  if(iMag[i]>highThreshold)
72  oMag[i] = highThreshold;
73  }
74  return true;
75 }
76 
77 
78 }
79