00001 /*========================================================================= 00002 00003 Program: Insight Segmentation & Registration Toolkit 00004 Module: $RCSfile: itkHistogramToLogProbabilityImageFilter.h,v $ 00005 Language: C++ 00006 Date: $Date: 2009-01-17 09:13:59 $ 00007 Version: $Revision: 1.8 $ 00008 00009 Copyright (c) Insight Software Consortium. All rights reserved. 00010 See ITKCopyright.txt or http://www.itk.org/HTML/Copyright.htm for details. 00011 00012 This software is distributed WITHOUT ANY WARRANTY; without even 00013 the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 00014 PURPOSE. See the above copyright notices for more information. 00015 00016 =========================================================================*/ 00017 #ifndef __itkHistogramLogProbabilityFunction_h 00018 #define __itkHistogramLogProbabilityFunction_h 00019 00020 #include "itkHistogramToImageFilter.h" 00021 00022 namespace itk 00023 { 00024 00046 namespace Function { 00047 template< class TInput, class TOutput=double > 00048 class HistogramLogProbabilityFunction 00049 { 00050 public: 00051 00052 //Probability function = Number of occurances in each bin / 00053 // Total Number of occurances. 00054 // 00055 // Returns pixels of float.. 00056 typedef TOutput OutputPixelType; 00057 00058 00059 HistogramLogProbabilityFunction(): 00060 m_TotalFrequency(1) {} 00061 00062 ~HistogramLogProbabilityFunction() {}; 00063 00064 inline OutputPixelType operator()( const TInput & A ) 00065 { 00066 if( A ) 00067 { 00068 return static_cast<OutputPixelType>(log( static_cast<OutputPixelType>(A) / 00069 static_cast<OutputPixelType>(m_TotalFrequency)) / vcl_log(2.0) ); 00070 } 00071 else 00072 { // Check for Log 0. Always assume that the frequency is atleast 1. 00073 return static_cast<OutputPixelType>(log( static_cast<OutputPixelType>(A+1) / 00074 static_cast<OutputPixelType>(m_TotalFrequency)) / vcl_log(2.0) ); 00075 } 00076 00077 } 00078 00079 void SetTotalFrequency( unsigned long n ) 00080 { 00081 m_TotalFrequency = n; 00082 } 00083 00084 unsigned long GetTotalFrequency( ) const 00085 { 00086 return m_TotalFrequency; 00087 } 00088 00089 private: 00090 unsigned long m_TotalFrequency; 00091 }; 00092 } 00093 00094 template <class THistogram, class TOutputPixel=double > 00095 class ITK_EXPORT HistogramToLogProbabilityImageFilter : 00096 public HistogramToImageFilter< THistogram, 00097 Function::HistogramLogProbabilityFunction< unsigned long, TOutputPixel > > 00098 { 00099 public: 00100 00102 typedef HistogramToLogProbabilityImageFilter Self; 00103 00105 typedef HistogramToImageFilter< THistogram, 00106 Function::HistogramLogProbabilityFunction< unsigned long, TOutputPixel > > 00107 Superclass; 00108 00109 typedef SmartPointer<Self> Pointer; 00110 typedef SmartPointer<const Self> ConstPointer; 00111 00113 itkTypeMacro( HistogramToLogProbabilityImageFilter, HistogramToImageFilter ); 00114 00116 itkNewMacro(Self); 00117 00118 protected: 00119 HistogramToLogProbabilityImageFilter() {} 00120 virtual ~HistogramToLogProbabilityImageFilter() {} 00121 00122 private: 00123 HistogramToLogProbabilityImageFilter(const Self&); //purposely not implemented 00124 void operator=(const Self&); //purposely not implemented 00125 00126 }; 00127 00128 } // end namespace itk 00129 00130 #endif 00131 00132 00133 00134