ITK/Examples/ItkVtkGlue/itkImageToVTKImageFilter

Many of the ITK examples use VTK to display the results. The files on this page provide a simple interface between ITK and VTK.

NOTE: If you download the entire ITK Wiki Examples Collection,, the ItkVtkGlue directory will be included. If you wish to just build a few examples, then you will need to download ItkVtkGlue and build it.

itkImageToVTKImageFilter.h

<source lang=cpp> /*=========================================================================

*
*  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.
*
*=========================================================================*/

1. ifndef __itkImageToVTKImageFilter_h
2. define __itkImageToVTKImageFilter_h

1. include "itkVTKImageExport.h"
2. include "vtkImageImport.h"
3. include "vtkImageData.h"

namespace itk {

/** \class ImageToVTKImageFilter

* \brief Converts an ITK image into a VTK image and plugs a
*  itk data pipeline to a VTK datapipeline.
*
*  This class puts together an itkVTKImageExporter and a vtkImageImporter.
*  It takes care of the details related to the connection of ITK and VTK
*  pipelines. The User will perceive this filter as an adaptor to which
*  an itk::Image can be plugged as input and a vtkImage is produced as
*  output.
*
* \ingroup   ImageFilters
*/

template <class TInputImage > class ITK_EXPORT ImageToVTKImageFilter : public ProcessObject { public:

 /** Standard class typedefs. */
 typedef ImageToVTKImageFilter       Self;
 typedef ProcessObject             Superclass;
 typedef SmartPointer<Self>        Pointer;
 typedef SmartPointer<const Self>  ConstPointer;

 /** Method for creation through the object factory. */
 itkNewMacro(Self);

 /** Run-time type information (and related methods). */
 itkTypeMacro(ImageToVTKImageFilter, ProcessObject);

 /** Some typedefs. */
 typedef TInputImage InputImageType;
 typedef typename InputImageType::ConstPointer  InputImagePointer;

 typedef VTKImageExport< InputImageType>        ExporterFilterType;
 typedef typename ExporterFilterType::Pointer   ExporterFilterPointer;

 /** Get the output in the form of a vtkImage.
     This call is delegated to the internal vtkImageImporter filter  */
 vtkImageData *  GetOutput() const;

 /** Set the input in the form of an itk::Image */
 void SetInput( const InputImageType * );

 /** Return the internal VTK image importer filter.
     This is intended to facilitate users the access
     to methods in the importer */
 vtkImageImport * GetImporter() const;

 /** Return the internal ITK image exporter filter.
     This is intended to facilitate users the access
     to methods in the exporter */
 ExporterFilterType * GetExporter() const;

 /** This call delegate the update to the importer */
 void Update();

protected:

 ImageToVTKImageFilter();
 virtual ~ImageToVTKImageFilter();

private:

 ImageToVTKImageFilter(const Self&); //purposely not implemented
 void operator=(const Self&); //purposely not implemented

 ExporterFilterPointer       m_Exporter;
 vtkImageImport *            m_Importer;

};

} // end namespace itk

1. ifndef ITK_MANUAL_INSTANTIATION
2. include "itkImageToVTKImageFilter.txx"
3. endif

1. endif

</source>

itkImageToVTKImageFilter.txx

<source lang=cpp> /*=========================================================================

*
*  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.
*
*=========================================================================*/

1. ifndef _itkImageToVTKImageFilter_txx
2. define _itkImageToVTKImageFilter_txx

1. include "itkImageToVTKImageFilter.h"

namespace itk {

/**

* Constructor
*/

template <class TInputImage> ImageToVTKImageFilter<TInputImage>

ImageToVTKImageFilter()

{

 m_Importer = vtkImageImport::New();
 m_Exporter = ExporterFilterType::New();

 m_Importer->SetUpdateInformationCallback(m_Exporter->GetUpdateInformationCallback());
 m_Importer->SetPipelineModifiedCallback(m_Exporter->GetPipelineModifiedCallback());
 m_Importer->SetWholeExtentCallback(m_Exporter->GetWholeExtentCallback());
 m_Importer->SetSpacingCallback(m_Exporter->GetSpacingCallback());
 m_Importer->SetOriginCallback(m_Exporter->GetOriginCallback());
 m_Importer->SetScalarTypeCallback(m_Exporter->GetScalarTypeCallback());
 m_Importer->SetNumberOfComponentsCallback(m_Exporter->GetNumberOfComponentsCallback());
 m_Importer->SetPropagateUpdateExtentCallback(m_Exporter->GetPropagateUpdateExtentCallback());
 m_Importer->SetUpdateDataCallback(m_Exporter->GetUpdateDataCallback());
 m_Importer->SetDataExtentCallback(m_Exporter->GetDataExtentCallback());
 m_Importer->SetBufferPointerCallback(m_Exporter->GetBufferPointerCallback());
 m_Importer->SetCallbackUserData(m_Exporter->GetCallbackUserData());

}

/**

* Destructor
*/

template <class TInputImage> ImageToVTKImageFilter<TInputImage>

~ImageToVTKImageFilter()

{

 if( m_Importer )
   {
   m_Importer->Delete();
   m_Importer = 0;
   }

}

/**

* Set an itk::Image as input
*/

template <class TInputImage> void ImageToVTKImageFilter<TInputImage>

SetInput( const InputImageType * inputImage )

{

 m_Exporter->SetInput( inputImage );

}

/**

* Get a vtkImage as output
*/

template <class TInputImage> vtkImageData * ImageToVTKImageFilter<TInputImage>

GetOutput() const

{

 return m_Importer->GetOutput();

}

/**

* Get the importer filter
*/

template <class TInputImage> vtkImageImport * ImageToVTKImageFilter<TInputImage>

GetImporter() const

{

 return m_Importer;

}

/**

* Get the exporter filter
*/

template <class TInputImage> typename ImageToVTKImageFilter<TInputImage>::ExporterFilterType * ImageToVTKImageFilter<TInputImage>

GetExporter() const

{

 return m_Exporter.GetPointer();

}

/**

* Delegate the Update to the importer
*/

template <class TInputImage> void ImageToVTKImageFilter<TInputImage>

Update()

{

 m_Importer->Update();

} } // end namespace itk

1. endif

</source>

QuickView.h

<source lang="cpp">

1. ifndef QuickView_H
2. define QuickView_H

1. include <vector>

1. include <itkImage.h>
2. include <itkRGBPixel.h>

class ImageInfo { public:

 typedef itk::Image<unsigned char, 2> ImageType;

 ImageInfo(ImageType *image, std::string description="")
 {
   m_Image = image;
   m_Description = description;
 }

 ImageType::Pointer m_Image;
 std::string        m_Description;

};

class RGBImageInfo { public:

 typedef itk::Image<itk::RGBPixel<unsigned char>, 2> ImageType;
 RGBImageInfo(ImageType *image, std::string description="")
 {
   m_Image = image;
   m_Description = description;
 }

 ImageType::Pointer m_Image;
 std::string        m_Description;

};

class QuickView {

public:

 template<class TImage> void AddImage(
   TImage *,
   bool FlipVertical=true,
   std::string Description="");
 template<class TImage> void AddRGBImage(
   TImage *,
   bool FlipVertical=true,
   std::string Description="");
 void Visualize();

private:

 std::vector<ImageInfo>    Images;
 std::vector<RGBImageInfo> RGBImages;

};

1. endif

</source>

QuickView.cxx

<source lang="cpp">

1. include "QuickView.h"

1. include "itkImage.h"
2. include "itkRGBPixel.h"
3. include "itkRescaleIntensityImageFilter.h"
4. include "itkFlipImageFilter.h"

1. include "vtkImageViewer.h"
2. include "vtkRenderWindowInteractor.h"
3. include "vtkSmartPointer.h"
4. include "vtkImageActor.h"
5. include "vtkActor2D.h"
6. include "vtkInteractorStyleImage.h"
7. include "vtkRenderer.h"
8. include "vtkCamera.h"
9. include "vtkTextProperty.h"
10. include "vtkTextMapper.h"

1. include "itkImageToVTKImageFilter.h"
2. include <algorithm>

typedef itk::Image<itk::RGBPixel<unsigned char>, 2> UnsignedCharRGBImageType; typedef itk::Image<itk::RGBPixel<float>, 2> FloatRGBImageType;

typedef itk::Image<unsigned char, 2> UnsignedCharImageType; typedef itk::Image<char, 2> CharImageType; typedef itk::Image<unsigned short, 2> UnsignedShortImageType; typedef itk::Image<short, 2> ShortImageType; typedef itk::Image<unsigned int, 2> UnsignedIntImageType; typedef itk::Image<int, 2> IntImageType; typedef itk::Image<unsigned long, 2> UnsignedLongImageType; typedef itk::Image<long, 2> LongImageType; typedef itk::Image<float, 2> FloatImageType; typedef itk::Image<double, 2> DoubleImageType;

template void QuickView::AddImage<CharImageType>(CharImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<UnsignedShortImageType>(UnsignedShortImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<ShortImageType>(ShortImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<UnsignedIntImageType>(UnsignedIntImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<IntImageType>(IntImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<UnsignedLongImageType>(UnsignedLongImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<LongImageType>(LongImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<FloatImageType>(FloatImageType *image, bool FlipVertical, std::string Description); template void QuickView::AddImage<DoubleImageType>(DoubleImageType *image, bool FlipVertical, std::string Description);

template< > void QuickView::AddImage<UnsignedCharImageType>(

 UnsignedCharImageType *image,
 bool FlipVertical,
 std::string Description)

{

 if (FlipVertical)
   {
   typedef itk::FlipImageFilter< UnsignedCharImageType> FlipFilterType;
   FlipFilterType::Pointer flipper = FlipFilterType::New();
   bool flipAxes[3] = { false, true, false };
   flipper = FlipFilterType::New();
   flipper->SetFlipAxes(flipAxes);
   flipper->SetInput(image);
   flipper->Update();
   ImageInfo myImage(flipper->GetOutput(), Description);
   this->Images.push_back(myImage);
   }
 else
   {
   ImageInfo myImage(image, Description);
   this->Images.push_back(myImage);
   }

}

template<class TImage> void QuickView::AddImage(

 TImage *image,
 bool FlipVertical,
 std::string Description)

{

 typedef itk::RescaleIntensityImageFilter<TImage, UnsignedCharImageType > rescaleFilterType;

 typename rescaleFilterType::Pointer rescaler = rescaleFilterType::New();
 rescaler->SetOutputMinimum(0);
 rescaler->SetOutputMaximum(255);
 rescaler->SetInput(image);
 rescaler->Update();
 
 this->AddImage(rescaler->GetOutput(), FlipVertical, Description);

}

template< > void QuickView::AddRGBImage<UnsignedCharRGBImageType>(

 UnsignedCharRGBImageType *image,
 bool FlipVertical,
 std::string Description)

{

 if (FlipVertical)
   {
   typedef itk::FlipImageFilter< UnsignedCharRGBImageType> FlipFilterType;
   FlipFilterType::Pointer flipper = FlipFilterType::New();
   bool flipAxes[3] = { false, true, false };
   flipper = FlipFilterType::New();
   flipper->SetFlipAxes(flipAxes);
   flipper->SetInput(image);
   flipper->Update();
   RGBImageInfo myImage(flipper->GetOutput());
   this->RGBImages.push_back(myImage);
   }
 else
   {
   RGBImageInfo myImage(image);
   this->RGBImages.push_back(myImage);
   }

}

void QuickView::Visualize() {

 unsigned int rendererSize = 300;

 // Setup the render window and interactor
 vtkSmartPointer<vtkRenderWindow> renderWindow =
   vtkSmartPointer<vtkRenderWindow>::New();
 renderWindow->SetSize(rendererSize * this->Images.size(), rendererSize);

 vtkSmartPointer<vtkRenderWindowInteractor> interactor =
   vtkSmartPointer<vtkRenderWindowInteractor>::New();
 interactor->SetRenderWindow(renderWindow);

 // Render all of the images
 double step = 1./(static_cast<double>(this->Images.size()+this->RGBImages.size()));
 std::vector<double*> viewports;

 typedef itk::ImageToVTKImageFilter<itk::Image<unsigned char, 2> >
   ConnectorType;
 typedef itk::ImageToVTKImageFilter<itk::Image<itk::RGBPixel<unsigned char>, 2> >
   RGBConnectorType;
 std::vector<ConnectorType::Pointer> connectors; // Force the connectors to persist (not lose scope) after each iteration of the loop
 std::vector<RGBConnectorType::Pointer>
   RGBconnectors; // Force the connectors to persist after each iteration of the loop

 double background[6] = {.4, .5, .6, .6, .5, .4};

 vtkSmartPointer<vtkCamera> camera = 
   vtkSmartPointer<vtkCamera>::New();

 for(unsigned int i = 0; i < this->Images.size(); i++)
   {
   ConnectorType::Pointer connector = ConnectorType::New();
   connectors.push_back(connector);
   connector->SetInput(this->Images[i].m_Image);
 
   // (xmin, ymin, xmax, ymax)
   double viewport[4] = {static_cast<double>(i)*step, 0.0, static_cast<double>(i+1)*step, 1.0};
   viewports.push_back(viewport);
   vtkSmartPointer<vtkImageActor> actor =
     vtkSmartPointer<vtkImageActor>::New();
   actor->SetInput(connector->GetOutput());

   // Setup renderer
   vtkSmartPointer<vtkRenderer> renderer =
     vtkSmartPointer<vtkRenderer>::New();
   renderWindow->AddRenderer(renderer);
   renderer->SetViewport(viewports[i]);
   renderer->SetBackground(background);
   renderer->SetActiveCamera(camera);
   std::rotate(background, background + 1, background + 6);

   if (this->Images[i].m_Description != "")
     {
     vtkSmartPointer<vtkTextProperty> textProperty =
       vtkSmartPointer<vtkTextProperty>::New();
     textProperty->SetFontSize(10);
     textProperty->SetFontFamilyToCourier();
     textProperty->SetJustificationToCentered();

     vtkSmartPointer<vtkTextMapper> textMapper =
       vtkSmartPointer<vtkTextMapper>::New();
     textMapper->SetTextProperty(textProperty);
     textMapper->SetInput(this->Images[i].m_Description.c_str());
     
     vtkSmartPointer<vtkActor2D> textActor =
       vtkSmartPointer<vtkActor2D>::New();
     textActor->SetMapper(textMapper);
     textActor->SetPosition(rendererSize/2, 16);
     renderer->AddActor(textActor);
     }

   renderer->AddActor(actor);
   renderer->ResetCamera();
   }

 unsigned int j = 0;
 for(unsigned int i = this->Images.size(); i < this->RGBImages.size(); i++, j++)
   {
   RGBConnectorType::Pointer connector = RGBConnectorType::New();
   RGBconnectors.push_back(connector);
   connector->SetInput(this->RGBImages[j].m_Image);

   // (xmin, ymin, xmax, ymax)
   double viewport[4] =
     {static_cast<double>(i)*step, 0.0, static_cast<double>(i+1)*step, 1.0};
   viewports.push_back(viewport);
   vtkSmartPointer<vtkImageActor> actor =
     vtkSmartPointer<vtkImageActor>::New();
   actor->SetInput(connector->GetOutput());

   // Setup renderer
   vtkSmartPointer<vtkRenderer> renderer =
     vtkSmartPointer<vtkRenderer>::New();
   renderWindow->AddRenderer(renderer);
   renderer->SetViewport(viewports[j]);
   renderer->SetBackground(background);
   renderer->SetActiveCamera(camera);
   std::rotate(background, background + 1, background + 6);

   if (this->RGBImages[j].m_Description != "")
     {
     vtkSmartPointer<vtkTextProperty> textProperty =
       vtkSmartPointer<vtkTextProperty>::New();
     textProperty->SetFontSize(10);
     textProperty->SetFontFamilyToCourier();
     textProperty->SetJustificationToCentered();

     vtkSmartPointer<vtkTextMapper> textMapper =
       vtkSmartPointer<vtkTextMapper>::New();
     textMapper->SetTextProperty(textProperty);
     textMapper->SetInput(this->RGBImages[j].m_Description.c_str());
     
     vtkSmartPointer<vtkActor2D> textActor =
       vtkSmartPointer<vtkActor2D>::New();
     textActor->SetMapper(textMapper);
     textActor->SetPosition(rendererSize/2, 16);
     renderer->AddActor(textActor);
     }

   renderer->AddActor(actor);
   renderer->ResetCamera();
   }

 renderWindow->Render();

 vtkSmartPointer<vtkInteractorStyleImage> style =
   vtkSmartPointer<vtkInteractorStyleImage>::New();
 interactor->SetInteractorStyle(style);
 interactor->Start();

} </source>