text: /*=========================================================================
   *
   *  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
   *  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.
   *
   *=========================================================================*/
  
  /**
   *
   *  This program illustrates the AdaptImageFilter
   *
   *  The example shows how an Accessor can be used to
   *  convert an RGBPixel image to an image that has
   *  just the red component.
   *
   *  That will allow to pass the red component of this
   *  image as input any filter that expects
   *  a float image
   *
   */
  
  
  #include "itkAdaptImageFilter.h"
  #include "itkRedPixelAccessor.h"
  #include "itkGreenPixelAccessor.h"
  #include "itkBluePixelAccessor.h"
  #include "itkFilterWatcher.h"
  
  #include "vnl/vnl_sample.h"
  
  
  //-------------------------------------
  //     Typedefs for convenience
  //-------------------------------------
  typedef itk::Image< itk::RGBPixel<float>,   2 > myRGBImageType;
  typedef itk::ImageRegionIteratorWithIndex< myRGBImageType >  myRGBIteratorType;
  
  typedef itk::RedPixelAccessor<float> myRedAccessorType;
  typedef itk::GreenPixelAccessor<float> myGreenAccessorType;
  typedef itk::BluePixelAccessor<float> myBlueAccessorType;
  
  typedef itk::Image< float,   2 > myImageType;
  typedef itk::ImageRegionIteratorWithIndex< myImageType >  myIteratorType;
  
  
  
  //-------------------------
  //
  //   Main code
  //
  //-------------------------
  int itkAdaptImageFilterTest(int, char* [] ) {
  
  
    myRGBImageType::SizeType size;
    size[0] = 2;
    size[1] = 2;
  
    myRGBImageType::IndexType index;
    index[0] = 0;
    index[1] = 0;
  
    myRGBImageType::RegionType region;
    region.SetIndex( index );
    region.SetSize(  size  );
  
    myRGBImageType::Pointer myImage = myRGBImageType::New();
  
  
    myImage->SetRegions( region );
    myImage->Allocate();
  
    myRGBIteratorType  it1( myImage, myImage->GetRequestedRegion() );
  
    // Value to initialize the pixels
    myRGBImageType::PixelType color;
  
    // Initializing all the pixel in the image
    it1.GoToBegin();
    while( !it1.IsAtEnd() )
      {
      color.Set( (float) vnl_sample_uniform(0.0, 1.0),
                 (float) vnl_sample_uniform(0.0, 1.0),
                 (float) vnl_sample_uniform(0.0, 1.0) );
      it1.Set(color);
      ++it1;
      }
  
    // Reading the values to verify the image content
    std::cout << "--- Initial image --- " << std::endl;
    it1.GoToBegin();
    while( !it1.IsAtEnd() )
      {
      const myRGBImageType::PixelType c( it1.Get() );
      std::cout << c.GetRed()   << "  ";
      std::cout << c.GetGreen() << "  ";
      std::cout << c.GetBlue()  << std::endl;
      ++it1;
      }
  
  
    bool passed = true;
  
    // Convert to a red image
    itk::AdaptImageFilter<myRGBImageType, myImageType, myRedAccessorType>::Pointer  adaptImageToRed = itk::AdaptImageFilter<myRGBImageType, myImageType, myRedAccessorType>::New();
    FilterWatcher redWatcher(adaptImageToRed, "Red");
    adaptImageToRed->SetInput(myImage);
    adaptImageToRed->UpdateLargestPossibleRegion();
    adaptImageToRed->SetFunctor(adaptImageToRed->GetFunctor());
  
    myIteratorType  it( adaptImageToRed->GetOutput(), adaptImageToRed->GetOutput()->GetRequestedRegion() );
  
    std::cout << "--- Red values --- " << std::endl;
  
    it.GoToBegin();
    it1.GoToBegin();
    while( !it.IsAtEnd() )
    {
    std::cout << it.Get()   << std::endl;
    if (it.Get() != it1.Get().GetRed())
      {
      passed = false;
      }
  
    ++it;
    ++it1;
    }
  
    // Convert to a green image
    itk::AdaptImageFilter<myRGBImageType, myImageType, myGreenAccessorType>::Pointer  adaptImageToGreen = itk::AdaptImageFilter<myRGBImageType, myImageType, myGreenAccessorType>::New();
    FilterWatcher greenWatcher(adaptImageToGreen, "Green");
  
    adaptImageToGreen->SetInput(myImage);
    adaptImageToGreen->UpdateLargestPossibleRegion();
  
    it = myIteratorType( adaptImageToGreen->GetOutput(), adaptImageToGreen->GetOutput()->GetRequestedRegion() );
  
    std::cout << "--- Green values --- " << std::endl;
  
    it.GoToBegin();
    it1.GoToBegin();
    while( !it.IsAtEnd() )
    {
    std::cout << it.Get()   << std::endl;
    if (it.Get() != it1.Get().GetGreen())
      {
      passed = false;
      }
  
    ++it;
    ++it1;
    }
  
    // Convert to a blue image
    itk::AdaptImageFilter<myRGBImageType, myImageType, myBlueAccessorType>::Pointer  adaptImageToBlue = itk::AdaptImageFilter<myRGBImageType, myImageType, myBlueAccessorType>::New();
    FilterWatcher blueWatcher(adaptImageToBlue, "Blue");
  
    adaptImageToBlue->SetInput(myImage);
    adaptImageToBlue->UpdateLargestPossibleRegion();
  
    it = myIteratorType( adaptImageToBlue->GetOutput(), adaptImageToBlue->GetOutput()->GetRequestedRegion() );
  
    std::cout << "--- Blue values --- " << std::endl;
  
    it.GoToBegin();
    it1.GoToBegin();
    while( !it.IsAtEnd() )
    {
    std::cout << it.Get()   << std::endl;
    if (it.Get() != it1.Get().GetBlue())
      {
      passed = false;
      }
  
    ++it;
    ++it1;
    }
  
    std::cout << std::endl;
    if (passed)
      {
      std::cout << "AdaptImageFilterTest passed." << std::endl;
      return EXIT_SUCCESS;
      }
    else
      {
      std::cerr << "AdaptImageFilterTest failed." << std::endl;
      return EXIT_FAILURE;
      }
  }
  
  
  
  