ITK  4.13.0
Insight Segmentation and Registration Toolkit
WikiExamples/SpectralAnalysis/InverseFFTImageFilter.cxx
#include "itkImage.h"
typedef itk::Image<float, 2> FloatImageType;
static void CreateImage(FloatImageType* const image);
int main(int argc, char*argv[])
{
FloatImageType::Pointer image;
// Verify input
if(argc < 2)
{
image = FloatImageType::New();
CreateImage(image);
//std::cerr << "Required: filename" << std::endl;
//return EXIT_FAILURE;
}
else
{
// Read the image
ReaderType::Pointer reader = ReaderType::New();
reader->SetFileName(argv[1]);
reader->Update();
image = reader->GetOutput();
}
// Define some types
typedef itk::Image<unsigned char, 2> UnsignedCharImageType;
// Compute the FFT
FFTType::Pointer fftFilter = FFTType::New();
fftFilter->SetInput(image);
fftFilter->Update();
// Compute the IFFT
//typedef itk::InverseFFTImageFilter<FFTType::OutputImageType, UnsignedCharImageType> IFFTType; // This does not work - output type seems to need to be float, but it is just an error, not a concept check error...
IFFTType::Pointer ifftFilter = IFFTType::New();
ifftFilter->SetInput(fftFilter->GetOutput());
ifftFilter->Update();
// QuickView viewer;
// viewer.AddImage(image.GetPointer());
// viewer.AddImage(ifftFilter->GetOutput());
// viewer.Visualize();
CastFilterType::Pointer castFilter = CastFilterType::New();
castFilter->SetInput(ifftFilter->GetOutput());
castFilter->Update();
WriterType::Pointer writer = WriterType::New();
writer->SetFileName("ifft.png");
writer->SetInput(castFilter->GetOutput());
writer->Update();
return EXIT_SUCCESS;
}
void CreateImage(FloatImageType* const image)
{
itk::Index<2> corner = {{0,0}};
itk::Size<2> size = {{200,200}};
itk::ImageRegion<2> region(corner, size);
image->SetRegions(region);
image->Allocate();
// Make a square
for(FloatImageType::IndexValueType r = 40; r < 100; r++)
{
for(FloatImageType::IndexValueType c = 40; c < 100; c++)
{
FloatImageType::IndexType pixelIndex = {{r,c}};
image->SetPixel(pixelIndex, 100);
}
}
}