ITK  5.1.0
Insight Segmentation and Registration Toolkit
itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h
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18 #ifndef itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex_h
19 #define itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex_h
20 
22 
23 namespace itk
24 {
118 template <typename TImage>
120  : public ImageRegionConstIteratorWithIndex<TImage>
121 {
122 public:
126 
129  using SizeType = typename Superclass::SizeType;
138 
139  using FrequencyType = typename ImageType::SpacingType;
140  using FrequencyValueType = typename ImageType::SpacingValueType;
144 
145  {
146  this->Init();
147  }
148 
152  : ImageRegionConstIteratorWithIndex<TImage>(ptr, region)
153  , m_ActualXDimensionIsOdd(false)
154  {
155  this->Init();
156  }
157 
166  , m_ActualXDimensionIsOdd(false)
167  {
168  this->Init();
169  }
170 
171  /*
172  * Image Index [0, N - 1] returns [0 to N/2] (positive) union [-N/2 + 1, -1] (negative).
173  * So index N/2 + 1 returns the bin -N/2 + 1.
174  * If first index of the image is not zero, it stills returns values in the same range.
175  * f = [0, 1, ..., N/2-1, -N/2, ..., -1] if N is even
176  * f = [0, 1, ..., (N-1)/2, -(N-1)/2, ..., -1] if N is odd
177  */
178  IndexType
180  {
181  IndexType freqInd;
182  freqInd.Fill(0);
183  for (unsigned int dim = 0; dim < TImage::ImageDimension; dim++)
184  {
185  if (this->m_PositionIndex[dim] <= m_LargestPositiveFrequencyIndex[dim])
186  {
187  freqInd[dim] = this->m_PositionIndex[dim] - this->m_MinIndex[dim];
188  }
189  else // -. From -N/2 + 1 (Nyquist if even) to -1 (-df in frequency)
190  {
191  freqInd[dim] = this->m_PositionIndex[dim] - (this->m_MaxIndex[dim] + 1);
192  }
193  }
194  return freqInd;
195  }
196 
217  GetFrequency() const
218  {
219  FrequencyType freq;
220  IndexType freqInd = this->GetFrequencyBin();
222 
223  for (unsigned int dim = 0; dim < TImage::ImageDimension; dim++)
224  {
225  freq[dim] = this->m_FrequencyOrigin[dim] + this->m_FrequencySpacing[dim] * freqInd[dim];
226  }
227  return freq;
228  }
229 
232  {
233  FrequencyValueType w2(0);
234  FrequencyType w(this->GetFrequency());
235 
236  for (unsigned int dim = 0; dim < TImage::ImageDimension; dim++)
237  {
238  w2 += w[dim] * w[dim];
239  }
240  return w2;
241  }
242 
252  itkGetConstReferenceMacro(LargestPositiveFrequencyIndex, IndexType);
253 
255  itkGetConstReferenceMacro(MinIndex, IndexType);
256 
258  itkGetConstReferenceMacro(MaxIndex, IndexType);
259 
261  itkGetConstReferenceMacro(FrequencyOrigin, FrequencyType);
262 
269  itkGetConstReferenceMacro(FrequencySpacing, FrequencyType);
270 
276  void
278  {
279  this->m_ActualXDimensionIsOdd = value;
280  SizeType sizeImage = this->m_Image->GetLargestPossibleRegion().GetSize();
281  auto size_estimated = 2 * (sizeImage[0] - 1);
282  size_estimated += this->GetActualXDimensionIsOdd() ? 1 : 0;
283  this->m_FrequencySpacing[0] = 1.0 / (this->m_Image->GetSpacing()[0] * size_estimated);
284  }
285  itkGetMacro(ActualXDimensionIsOdd, bool);
286  itkBooleanMacro(ActualXDimensionIsOdd);
288 
289 private:
293  void
295  {
296  SizeType sizeImage = this->m_Image->GetLargestPossibleRegion().GetSize();
297  this->m_MinIndex = this->m_Image->GetLargestPossibleRegion().GetIndex();
298  this->m_MaxIndex = this->m_Image->GetLargestPossibleRegion().GetUpperIndex();
299  for (unsigned int dim = 0; dim < ImageType::ImageDimension; dim++)
300  {
302  static_cast<FrequencyValueType>(this->m_MinIndex[dim] + sizeImage[dim] / 2);
303  // Set frequency metadata.
304  // Origin of frequencies is zero after a FFT.
305  this->m_FrequencyOrigin[dim] = 0.0;
306  // SamplingFrequency = 1.0 / SpatialImageSpacing
307  // Freq_BinSize = SamplingFrequency / Size
308  this->m_FrequencySpacing[dim] = 1.0 / (this->m_Image->GetSpacing()[dim] * sizeImage[dim]);
309  }
310  // Corrections for Hermitian
311  // The fastest index has no negative frequencies.
312  this->m_LargestPositiveFrequencyIndex[0] = static_cast<FrequencyValueType>(this->m_MaxIndex[0]);
313  // In fastest dimension only:
314  // Size_estimated_original = 2 * (Size_current - 1 )
315  // Where size_current is the size of the output of RealToHalfHermitianFFT
316  // Ex: Size Original = 10, Current = 6, Estimated = 10.
317  // Size Original = 11, Current = 6, Estimated = 10.
318  auto size_estimated = 2 * (sizeImage[0] - 1);
319  size_estimated += this->GetActualXDimensionIsOdd() ? 1 : 0;
320  this->m_FrequencySpacing[0] = 1.0 / (this->m_Image->GetSpacing()[0] * size_estimated);
321  }
323 
329  bool m_ActualXDimensionIsOdd{ false };
330 };
331 } // end namespace itk
332 #endif
itk::ImageRegionConstIteratorWithIndex::PixelType
typename Superclass::PixelType PixelType
Definition: itkImageRegionConstIteratorWithIndex.h:149
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::FrequencyType
typename ImageType::SpacingType FrequencyType
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:139
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::m_MaxIndex
IndexType m_MaxIndex
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:326
itk::ImageConstIteratorWithIndex::SizeType
typename TImage::SizeType SizeType
Definition: itkImageConstIteratorWithIndex.h:109
itkImageRegionConstIteratorWithIndex.h
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::SetActualXDimensionIsOdd
void SetActualXDimensionIsOdd(bool value)
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:277
itk::ImageRegionConstIteratorWithIndex
A multi-dimensional iterator templated over image type that walks an image region and is specialized ...
Definition: itkImageRegionConstIteratorWithIndex.h:128
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::m_FrequencyOrigin
FrequencyType m_FrequencyOrigin
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:327
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::IndexType
typename Superclass::IndexType IndexType
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:128
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::Init
void Init()
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:294
itk::ImageConstIteratorWithIndex::m_Image
TImage::ConstWeakPointer m_Image
Definition: itkImageConstIteratorWithIndex.h:296
itk::ImageRegionConstIteratorWithIndex::PixelContainerPointer
typename Superclass::PixelContainerPointer PixelContainerPointer
Definition: itkImageRegionConstIteratorWithIndex.h:147
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::m_LargestPositiveFrequencyIndex
IndexType m_LargestPositiveFrequencyIndex
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:324
itk::ImageConstIteratorWithIndex::PixelContainerPointer
typename PixelContainer::Pointer PixelContainerPointer
Definition: itkImageConstIteratorWithIndex.h:122
itk::ImageRegionConstIteratorWithIndex::ImageType
typename Superclass::ImageType ImageType
Definition: itkImageRegionConstIteratorWithIndex.h:145
itk::ImageConstIteratorWithIndex::PixelType
typename TImage::PixelType PixelType
Definition: itkImageConstIteratorWithIndex.h:128
itk::ImageRegionConstIteratorWithIndex::OffsetType
typename Superclass::OffsetType OffsetType
Definition: itkImageRegionConstIteratorWithIndex.h:143
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex
A multi-dimensional iterator templated over image type that walks pixels within a region and is speci...
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:119
itk::ImageConstIteratorWithIndex::IndexType
typename TImage::IndexType IndexType
Definition: itkImageConstIteratorWithIndex.h:105
itk::ImageConstIteratorWithIndex::InternalPixelType
typename TImage::InternalPixelType InternalPixelType
Definition: itkImageConstIteratorWithIndex.h:125
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::m_ActualXDimensionIsOdd
bool m_ActualXDimensionIsOdd
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:329
itk::ImageRegionConstIteratorWithIndex::RegionType
typename Superclass::RegionType RegionType
Definition: itkImageRegionConstIteratorWithIndex.h:144
itk::ImageConstIteratorWithIndex::AccessorType
typename TImage::AccessorType AccessorType
Definition: itkImageConstIteratorWithIndex.h:132
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::m_MinIndex
IndexType m_MinIndex
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:325
itk::ImageRegionConstIteratorWithIndex::IndexType
typename Superclass::IndexType IndexType
Definition: itkImageRegionConstIteratorWithIndex.h:141
itk::ImageConstIteratorWithIndex
A base class for multi-dimensional iterators templated over image type that are designed to efficient...
Definition: itkImageConstIteratorWithIndex.h:92
itk::ImageRegionConstIteratorWithIndex::AccessorType
typename Superclass::AccessorType AccessorType
Definition: itkImageRegionConstIteratorWithIndex.h:150
itk::ImageRegionConstIteratorWithIndex::InternalPixelType
typename Superclass::InternalPixelType InternalPixelType
Definition: itkImageRegionConstIteratorWithIndex.h:148
itk::ImageRegionConstIteratorWithIndex::SizeType
typename Superclass::SizeType SizeType
Definition: itkImageRegionConstIteratorWithIndex.h:142
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::GetFrequencyBin
IndexType GetFrequencyBin() const
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:179
itk
The "itk" namespace contains all Insight Segmentation and Registration Toolkit (ITK) classes....
Definition: itkArray.h:26
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex
FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex(const Superclass &it)
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:164
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex
FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex()
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:142
itk::ImageConstIteratorWithIndex::RegionType
typename TImage::RegionType RegionType
Definition: itkImageConstIteratorWithIndex.h:113
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::GetFrequency
FrequencyType GetFrequency() const
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:217
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex
FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex(const TImage *ptr, const RegionType &region)
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:151
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::m_FrequencySpacing
FrequencyType m_FrequencySpacing
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:328
itk::ImageConstIteratorWithIndex::m_PositionIndex
IndexType m_PositionIndex
Definition: itkImageConstIteratorWithIndex.h:298
itk::ImageRegionConstIteratorWithIndex::PixelContainer
typename Superclass::PixelContainer PixelContainer
Definition: itkImageRegionConstIteratorWithIndex.h:146
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::GetActualXDimensionIsOdd
virtual bool GetActualXDimensionIsOdd()
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::FrequencyValueType
typename ImageType::SpacingValueType FrequencyValueType
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:140
itk::FrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex::GetFrequencyModuloSquare
FrequencyValueType GetFrequencyModuloSquare() const
Definition: itkFrequencyHalfHermitianFFTLayoutImageRegionConstIteratorWithIndex.h:231
itk::ImageConstIteratorWithIndex::ImageType
TImage ImageType
Definition: itkImageConstIteratorWithIndex.h:116
itk::ImageConstIteratorWithIndex::PixelContainer
typename TImage::PixelContainer PixelContainer
Definition: itkImageConstIteratorWithIndex.h:121
itk::ImageConstIteratorWithIndex::OffsetType
typename TImage::OffsetType OffsetType
Definition: itkImageConstIteratorWithIndex.h:136