ITK  5.3.0
Insight Toolkit
itkPathFunctions.h
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18 #ifndef itkPathFunctions_h
19 #define itkPathFunctions_h
20 
21 #include "itkChainCodePath.h"
22 #include "itkFourierSeriesPath.h"
23 #include <cmath>
24 
25 namespace itk
26 {
31 template <typename TChainCodePath, typename TPathInput>
32 void
33 MakeChainCodeTracePath(TChainCodePath & chainPath, const TPathInput & inPath, bool restrictMovement = false)
34 {
35  using OffsetType = typename TChainCodePath::OffsetType;
36  using ChainInputType = typename TChainCodePath::InputType;
37  using InPathInputType = typename TPathInput::InputType;
38 
39  OffsetType offset, tempOffset, zeroOffset;
40  InPathInputType inPathInput;
41  int dimension = OffsetType::GetOffsetDimension();
42 
43  zeroOffset.Fill(0);
44 
45  chainPath.Clear();
46  inPathInput = inPath.StartOfInput();
47  chainPath.SetStart(inPath.EvaluateToIndex(inPathInput));
48 
49  for (ChainInputType chainInput = 0;;)
50  {
51  offset = inPath.IncrementInput(inPathInput);
52  if (zeroOffset == offset)
53  {
54  break;
55  }
56 
57  if (!restrictMovement)
58  {
59  chainPath.InsertStep(chainInput++, offset);
60  }
61  else
62  {
63  for (int d = 0; d < dimension; ++d)
64  {
65  tempOffset.Fill(0);
66  tempOffset[d] = offset[d];
67  chainPath.InsertStep(chainInput++, tempOffset);
68  }
69  }
70  }
71 }
72 
79 template <typename TFourierSeriesPath, typename TChainCodePath>
80 void
81 MakeFourierSeriesPathTraceChainCode(TFourierSeriesPath & FSPath,
82  const TChainCodePath & chainPath,
83  unsigned int numHarmonics = 8)
84 {
86  using OffsetType = typename TFourierSeriesPath::OffsetType;
89 
90  using FSInputType = typename TFourierSeriesPath::InputType;
91  using ChainInputType = typename TChainCodePath::InputType;
92 
93  IndexType index;
94  VectorType indexVector;
95  VectorType cosCoefficient;
96  VectorType sinCoefficient;
97  FSInputType theta;
98  int dimension = OffsetType::GetOffsetDimension();
99  size_t numSteps = chainPath.NumberOfSteps();
100 
101  const double PI = 4.0 * std::atan(1.0);
102 
103  FSPath.Clear();
104 
105  // Adjust our private copy of numHarmonics if necessary
106  if (numHarmonics <= 1)
107  {
108  numHarmonics = 2;
109  }
110  else if (numHarmonics * 2 > numSteps)
111  {
112  numHarmonics = numSteps / 2;
113  }
114 
115  for (unsigned n = 0; n < numHarmonics; ++n)
116  {
117  index = chainPath.GetStart();
118  cosCoefficient.Fill(0.0);
119  sinCoefficient.Fill(0.0);
120 
121  for (ChainInputType step = 0; step < numSteps; ++step)
122  {
123  index += chainPath.Evaluate(step);
124  theta = 2 * n * PI * (double(step + 1)) / numSteps;
125 
126  // turn the current index into a vector
127  for (int d = 0; d < dimension; ++d)
128  {
129  indexVector[d] = index[d];
130  }
131  cosCoefficient += indexVector * (std::cos(theta) / numSteps);
132  sinCoefficient += indexVector * (std::sin(theta) / numSteps);
133  }
134 
135  FSPath.AddHarmonic(cosCoefficient, sinCoefficient);
136  }
137 }
138 } // end namespace itk
139 
140 #endif
itk::MakeChainCodeTracePath
void MakeChainCodeTracePath(TChainCodePath &chainPath, const TPathInput &inPath, bool restrictMovement=false)
Definition: itkPathFunctions.h:33
itk::GTest::TypedefsAndConstructors::Dimension2::VectorType
ImageBaseType::SpacingType VectorType
Definition: itkGTestTypedefsAndConstructors.h:53
itkChainCodePath.h
itk::GTest::TypedefsAndConstructors::Dimension2::IndexType
ImageBaseType::IndexType IndexType
Definition: itkGTestTypedefsAndConstructors.h:50
itk::MakeFourierSeriesPathTraceChainCode
void MakeFourierSeriesPathTraceChainCode(TFourierSeriesPath &FSPath, const TChainCodePath &chainPath, unsigned int numHarmonics=8)
Definition: itkPathFunctions.h:81
itk
The "itk" namespace contains all Insight Segmentation and Registration Toolkit (ITK) classes....
Definition: itkAnnulusOperator.h:24
itkFourierSeriesPath.h