ITK/Examples/EdgesAndGradients/DerivativeImageFilter

This example demonstrates how to compute the derivative of an image in a specified axis-aligned direction. The original image and its x derivative are displayed on the screen.

DerivativeImageFilter.cxx

<source lang="cpp">

1. include "itkImage.h"
2. include "itkImageFileReader.h"
3. include "itkDerivativeImageFilter.h"

1. include "QuickView.h"

int main(int argc, char * argv[]) {

 // Verify command line arguments
 if( argc < 2 )
   {
   std::cerr << "Usage: " << std::endl;
   std::cerr << argv[0] << " inputImageFile" << std::endl;
   return EXIT_FAILURE;
   }

 // Parse command line arguments
 std::string inputFilename = argv[1];

 // Setup types
 typedef itk::Image< float,  2 >        FloatImageType;
 typedef itk::Image< unsigned char, 2 > UnsignedCharImageType;

 typedef itk::ImageFileReader< UnsignedCharImageType >  readerType;

 typedef itk::DerivativeImageFilter<

UnsignedCharImageType, FloatImageType > filterType;

 // Create and setup a reader
 readerType::Pointer reader = readerType::New();
 reader->SetFileName( inputFilename.c_str() );

 // Create and setup a derivative filter
 filterType::Pointer derivativeFilter = filterType::New();
 derivativeFilter->SetInput( reader->GetOutput() );
 derivativeFilter->SetDirection(0); // "x" axis

 QuickView viewer;

 viewer.AddImage<UnsignedCharImageType>(reader->GetOutput());
 viewer.AddImage<FloatImageType>(derivativeFilter->GetOutput());
 viewer.Visualize();

 return EXIT_SUCCESS;

} </source>

CMakeLists.txt

<source lang="cmake"> cmake_minimum_required(VERSION 2.6)

PROJECT(DerivativeImageFilter)

include_directories(/home/doriad/src/ITK/Wrapping/WrapITK/ExternalProjects/ItkVtkGlue/src/)

FIND_PACKAGE(VTK REQUIRED) INCLUDE(${VTK_USE_FILE})

FIND_PACKAGE(ITK REQUIRED) INCLUDE(${ITK_USE_FILE})

ADD_EXECUTABLE(DerivativeImageFilter DerivativeImageFilter.cxx) TARGET_LINK_LIBRARIES(DerivativeImageFilter vtkHybrid ITKBasicFilters ITKIO ITKCommon)

</source>