ITK  5.2.0
Insight Toolkit
Examples/IO/ComplexImageReadWrite.cxx
/*=========================================================================
*
* Copyright NumFOCUS
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*=========================================================================*/
// Software Guide : BeginLatex
//
// This example illustrates how to read and write an image of pixel type
// \code{std::complex}. The complex type is defined as an integral part of
// the C++ language. The characteristics of the type are specified in the C++
// standard document in Chapter 26 "Numerics Library", page 565, in
// particular in section 26.2~\cite{CPPStandard1998}.
//
// We start by including the headers of the complex class, the image, and the
// reader and writer classes.
//
// \index{itk::ImageFileRead!Complex images}
// \index{itk::ImageFileWrite!Complex images}
// \index{Complex images!Instantiation}
// \index{Complex images!Reading}
// \index{Complex images!Writing}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
#include <complex>
#include "itkImage.h"
// Software Guide : EndCodeSnippet
int
main(int argc, char * argv[])
{
// Verify the number of parameters in the command line
if (argc < 3)
{
std::cerr << "Usage: " << std::endl;
std::cerr << argv[0] << " inputImageFile outputImageFile " << std::endl;
return EXIT_FAILURE;
}
// Software Guide : BeginLatex
//
// The image dimension and pixel type must be declared. In this case we use
// the \code{std::complex<>} as the pixel type. Using the dimension and
// pixel type we proceed to instantiate the image type.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
constexpr unsigned int Dimension = 2;
using PixelType = std::complex<float>;
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The image file reader and writer types are instantiated using the image
// type. We can then create objects for both of them.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using ReaderType = itk::ImageFileReader<ImageType>;
using WriterType = itk::ImageFileWriter<ImageType>;
ReaderType::Pointer reader = ReaderType::New();
WriterType::Pointer writer = WriterType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// File names should be provided for both the reader and the writer. In this
// particular example we take those file names from the command line
// arguments.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
reader->SetFileName(argv[1]);
writer->SetFileName(argv[2]);
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Here we simply connect the output of the reader as input to the writer.
// This simple program could be used for converting complex images from one
// file format to another.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
writer->SetInput(reader->GetOutput());
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The execution of this short pipeline is triggered by invoking the
// \code{Update()} method of the writer. This invocation must be placed
// inside a try/catch block since its execution may result in exceptions
// being thrown.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
try
{
writer->Update();
}
catch (const itk::ExceptionObject & err)
{
std::cerr << "ExceptionObject caught !" << std::endl;
std::cerr << err << std::endl;
return EXIT_FAILURE;
}
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// For a more interesting use of this code, you may want to add a filter in
// between the reader and the writer and perform any complex image to
// complex image operation. A practical application of this code is
// presented in section~\ref{sec:FrequencyDomain} in the context of Fourier
// analysis.
//
// Software Guide : EndLatex
return EXIT_SUCCESS;
}
itkImageFileReader.h
itkImage.h
itk::ImageFileReader
Data source that reads image data from a single file.
Definition: itkImageFileReader.h:75
itk::ImageFileWriter
Writes image data to a single file.
Definition: itkImageFileWriter.h:87
itkImageFileWriter.h
itk::Image
Templated n-dimensional image class.
Definition: itkImage.h:86
itk::GTest::TypedefsAndConstructors::Dimension2::Dimension
constexpr unsigned int Dimension
Definition: itkGTestTypedefsAndConstructors.h:44