ITK  4.9.0
Insight Segmentation and Registration Toolkit
Examples/Filtering/SignedDanielssonDistanceMapImageFilter.cxx
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*
* Copyright Insight Software Consortium
*
* 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
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* See the License for the specific language governing permissions and
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// Software Guide : BeginLatex
//
// This example illustrates the use of the
// \doxygen{SignedDanielssonDistanceMapImageFilter}. This filter generates a
// distance map by running Danielsson distance map twice, once on the input
// image and once on the flipped image.
//
// \index{itk::Signed\-Danielsson\-Distance\-Map\-Image\-Filter!Instantiation}
// \index{itk::Signed\-Danielsson\-Distance\-Map\-Image\-Filter!Header}
//
// The first step required to use this filter is to include its header file.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
// Software Guide : EndCodeSnippet
#include "itkImage.h"
int main( int argc, char * argv[] )
{
if( argc < 5 )
{
std::cerr << "Usage: " << argv[0];
std::cerr << " inputImageFile outputDistanceMapImageFile ";
std::cerr << " outputVoronoiMapImageFilter ";
std::cerr << " outputVectorMapImageFilter ";
std::cerr << std::endl;
return EXIT_FAILURE;
}
// Software Guide : BeginLatex
//
// Then we must decide what pixel types to use for the input and output
// images. Since the output will contain distances measured in pixels, the
// pixel type should be able to represent at least the width of the image,
// or said in $N$-dimensional terms, the maximum extension along all the dimensions.
// The input and output image types are now defined using their respective
// pixel type and dimension.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
typedef unsigned char InputPixelType;
typedef float OutputPixelType;
typedef unsigned short VoronoiPixelType;
const unsigned int Dimension = 2;
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The only change with respect to the previous example is to replace the
// DanielssonDistanceMapImageFilter with the
// SignedDanielssonDistanceMapImageFilter.
//
// SoftwareGuide : EndLatex
// Software Guide : BeginCodeSnippet
InputImageType,
OutputImageType,
VoronoiImageType > FilterType;
FilterType::Pointer filter = FilterType::New();
// Software Guide : EndCodeSnippet
OutputImageType, OutputImageType > RescalerType;
RescalerType::Pointer scaler = RescalerType::New();
// Software Guide : BeginLatex
//
// The distances inside the circle are defined to be negative, while the
// distances outside the circle are positive. To change the convention,
// use the \code{InsideIsPositive(bool)} function.
//
// Software Guide : EndLatex
// Reader and Writer types are instantiated.
//
typedef itk::ImageFileWriter< VoronoiImageType > VoronoiWriterType;
ReaderType::Pointer reader = ReaderType::New();
WriterType::Pointer writer = WriterType::New();
reader->SetFileName( argv[1] );
writer->SetFileName( argv[2] );
// The input to the filter is taken from a reader and its output is passed
// to a \doxygen{RescaleIntensityImageFilter} and then to a writer.
filter->SetInput( reader->GetOutput() );
scaler->SetInput( filter->GetOutput() );
writer->SetInput( scaler->GetOutput() );
scaler->SetOutputMaximum( 65535L );
scaler->SetOutputMinimum( 0L );
try
{
writer->Update();
}
catch( itk::ExceptionObject & exp )
{
std::cerr << "Exception caught !" << std::endl;
std::cerr << exp << std::endl;
}
const char * voronoiMapFileName = argv[3];
// The Voronoi map is obtained with the \code{GetVoronoiMap()} method. In
// the lines below we connect this output to the intensity rescaler and
// save the result in a file.
//
// \index{itk::Danielsson\-Distance\-Map\-Image\-Filter!GetVoronoiMap()}
//
VoronoiWriterType::Pointer voronoiWriter = VoronoiWriterType::New();
voronoiWriter->SetFileName( voronoiMapFileName );
voronoiWriter->SetInput( filter->GetVoronoiMap() );
try
{
voronoiWriter->Update();
}
catch( itk::ExceptionObject & exp )
{
std::cerr << "Exception caught !" << std::endl;
std::cerr << exp << std::endl;
}
// The distance filter also produces an image of \doxygen{Offset} pixels
// representing the vectorial distance to the closest object in the scene.
// The type of this output image is defined by the VectorImageType
// trait of the filter type.
typedef FilterType::VectorImageType OffsetImageType;
// We can use this type for instantiating an \doxygen{ImageFileWriter} type
// and creating an object of this class in the following lines.
typedef itk::ImageFileWriter< OffsetImageType > WriterOffsetType;
WriterOffsetType::Pointer offsetWriter = WriterOffsetType::New();
offsetWriter->SetInput( filter->GetVectorDistanceMap() );
offsetWriter->SetFileName( argv[4] );
try
{
offsetWriter->Update();
}
catch( itk::ExceptionObject & exp )
{
std::cerr << "Exception caught !" << std::endl;
std::cerr << exp << std::endl;
}
// Software Guide : BeginLatex
//
// \begin{figure}
// \center
// \includegraphics[width=0.32\textwidth]{Circle}
// \includegraphics[width=0.32\textwidth]{SignedDanielssonDistanceMapImageFilterOutput}
// \itkcaption[SignedDanielssonDistanceMapImageFilter
// output]{SignedDanielssonDistanceMapImageFilter applied on a binary circle image.
// The intensity has been rescaled for purposes of display.}
// \label{fig:SignedDanielssonDistanceMapImageFilterInputOutput}
// \end{figure}
//
// Figure \ref{fig:SignedDanielssonDistanceMapImageFilterInputOutput} illustrates
// the effect of this filter. The
// input image and the distance map are shown.
//
// \index{Distance Map!itk::Signed\-Danielsson\-Distance\-Map\-Image\-Filter}
//
// Software Guide : EndLatex
return EXIT_SUCCESS;
}