CLAM-Development  1.4.0
ERB_Space_Gen.cxx
Go to the documentation of this file.
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 
23 //Implemented from Slaney's Auditory Toolbox (http://rvl4.ecn.purdue.edu/~malcolm/interval/1998-010/)
24 
25 
26 #include "ERB_Space_Gen.hxx"
27 #include "CLAM_Math.hxx"
28 
29 namespace CLAM
30 {
31 
33 {
35 }
36 
38 {
39  Configure(c);
40 }
41 
42 
44 
45 bool ERB_SpaceGen::ConcreteConfigure(const ProcessingConfig& c)
46 {
47  CopyAsConcreteConfig( mConfig, c );
48 
49  mNumFilter=mConfig.GetNumFilter();
50  mLowFreq=(TData)mConfig.GetLowFreq();
51  mHighFreq=(TData)mConfig.GetHighFreq();
52 
53  return true;
54 }
55 
57 {
58  int i;
59 
60  //Change the following three parameters if you wish to use a different
61  //ERB scale. Must change in MakeERBCoeffs too.
62  double earQ = 9.26449; // Glasberg and Moore Parameters
63  double minBW = 24.7;
64 
65  // All of the followFreqing expressions are derived in Apple TR #35, "An
66  // Efficient Implementation of the Patterson-Holdsworth Cochlear
67  // Filter Bank." See pages 33-34.
68  for( i=0; i<mNumFilter; i++)
69  {
70  mERBFreqs[i]=-(earQ*minBW)
71  + std::exp((i+1)*(-std::log(mHighFreq + earQ*minBW) + std::log(mLowFreq + earQ*minBW))/mNumFilter) * (mHighFreq + earQ*minBW);
72  }
73 
74  return true;
75 }
76 
77 } // namespace CLAM
78