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| ==ForwardFFTImageFilter.cxx==
| | {{warning|1=The media wiki content on this page is no longer maintained. The examples presented on the https://itk.org/Wiki/* pages likely require ITK version 4.13 or earlier releases. In many cases, the examples on this page no longer conform to the best practices for modern ITK versions.}} |
| <source lang="cpp">
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| #include "itkCastImageFilter.h"
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| #include "itkImage.h"
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| #include "itkRescaleIntensityImageFilter.h"
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| #include "itkForwardFFTImageFilter.h"
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| #include "itkComplexToRealImageFilter.h"
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| #include "itkComplexToImaginaryImageFilter.h"
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| #include "itkComplexToModulusImageFilter.h"
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| #include "itkImageFileReader.h"
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| #include "itkImageFileWriter.h"
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| | |
| #include "QuickView.h"
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| | |
| typedef itk::Image<float, 2> FloatImageType;
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| | |
| void CreateImage(FloatImageType* const image);
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| | |
| int main(int argc, char*argv[])
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| { | |
| FloatImageType::Pointer image;
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| // Verify input
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| if(argc < 2)
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| {
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| image = FloatImageType::New();
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| CreateImage(image);
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| //std::cerr << "Required: filename" << std::endl;
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| //return EXIT_FAILURE;
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| }
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| else
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| {
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| // Read the image
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| typedef itk::ImageFileReader<FloatImageType> ReaderType;
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| ReaderType::Pointer reader = ReaderType::New();
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| reader->SetFileName(argv[1]);
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| reader->Update();
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| | |
| image = reader->GetOutput();
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| }
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| | |
| // Define some types
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| typedef itk::Image<unsigned char, 2> UnsignedCharImageType;
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| | |
| // Compute the FFT
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| typedef itk::ForwardFFTImageFilter<FloatImageType> FFTType;
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| FFTType::Pointer fftFilter = FFTType::New();
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| fftFilter->SetInput(image);
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| fftFilter->Update();
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| | |
| // Extract the real part
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| typedef itk::ComplexToRealImageFilter<FFTType::OutputImageType, FloatImageType> RealFilterType;
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| RealFilterType::Pointer realFilter = RealFilterType::New();
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| realFilter->SetInput(fftFilter->GetOutput());
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| realFilter->Update();
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| | |
| typedef itk::RescaleIntensityImageFilter< FloatImageType, UnsignedCharImageType > RescaleFilterType;
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| RescaleFilterType::Pointer realRescaleFilter = RescaleFilterType::New();
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| realRescaleFilter->SetInput(realFilter->GetOutput());
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| realRescaleFilter->SetOutputMinimum(0);
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| realRescaleFilter->SetOutputMaximum(255);
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| realRescaleFilter->Update();
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| | |
| // Extract the imaginary part
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| typedef itk::ComplexToImaginaryImageFilter<FFTType::OutputImageType, FloatImageType> ImaginaryFilterType;
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| ImaginaryFilterType::Pointer imaginaryFilter = ImaginaryFilterType::New();
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| imaginaryFilter->SetInput(fftFilter->GetOutput());
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| imaginaryFilter->Update();
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| | |
| RescaleFilterType::Pointer imaginaryRescaleFilter = RescaleFilterType::New();
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| imaginaryRescaleFilter->SetInput(imaginaryFilter->GetOutput());
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| imaginaryRescaleFilter->SetOutputMinimum(0);
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| imaginaryRescaleFilter->SetOutputMaximum(255);
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| imaginaryRescaleFilter->Update();
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| | |
| // Compute the magnitude
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| typedef itk::ComplexToModulusImageFilter<FFTType::OutputImageType, FloatImageType> ModulusFilterType;
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| ModulusFilterType::Pointer modulusFilter = ModulusFilterType::New();
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| modulusFilter->SetInput(fftFilter->GetOutput());
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| modulusFilter->Update();
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| | |
| RescaleFilterType::Pointer magnitudeRescaleFilter = RescaleFilterType::New();
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| magnitudeRescaleFilter->SetInput(modulusFilter->GetOutput());
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| magnitudeRescaleFilter->SetOutputMinimum(0);
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| magnitudeRescaleFilter->SetOutputMaximum(255);
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| magnitudeRescaleFilter->Update();
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| | |
| // QuickView viewer;
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| // viewer.AddImage(image.GetPointer());
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| // viewer.AddImage(realRescaleFilter->GetOutput()); | |
| // viewer.AddImage(imaginaryRescaleFilter->GetOutput());
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| // viewer.AddImage(magnitudeRescaleFilter->GetOutput());
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| // viewer.Visualize();
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| | |
| // Write the images | |
| typedef itk::ImageFileWriter<UnsignedCharImageType> WriterType;
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|
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| WriterType::Pointer realWriter = WriterType::New();
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| realWriter->SetFileName("real.png");
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| realWriter->SetInput(realRescaleFilter->GetOutput());
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| realWriter->Update();
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|
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| WriterType::Pointer imaginaryWriter = WriterType::New();
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| imaginaryWriter->SetFileName("imaginary.png");
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| imaginaryWriter->SetInput(imaginaryRescaleFilter->GetOutput());
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| imaginaryWriter->Update();
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|
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| WriterType::Pointer magnitudeWriter = WriterType::New();
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| magnitudeWriter->SetFileName("magnitude.png");
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| magnitudeWriter->SetInput(magnitudeRescaleFilter->GetOutput());
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| magnitudeWriter->Update();
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|
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| return EXIT_SUCCESS;
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| }
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| | |
| void CreateImage(FloatImageType* const image)
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| {
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| itk::Index<2> corner = {{0,0}};
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| itk::Size<2> size = {{200,200}};
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| itk::ImageRegion<2> region(corner, size);
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| image->SetRegions(region);
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| image->Allocate();
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| | |
| // Make a square
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| for(unsigned int r = 40; r < 100; r++)
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| {
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| for(unsigned int c = 40; c < 100; c++)
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| {
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| FloatImageType::IndexType pixelIndex = {{r,c}};
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| image->SetPixel(pixelIndex, 100);
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| }
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| }
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| }
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| | |
| </source>
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| | |
| {{ITKVTKCMakeLists|ForwardFFTImageFilter|}}
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