typename PatchExtractor<PValue>::ImageType::Pointer 
PatchExtractor<PValue>::ExtractPatch()
{
	ContIndexType startIndex;
	for(unsigned int i = 0; i < 2; i++)
	{
		startIndex[i] = m_Center[i] - (m_Size[i] / 2.0);
	}
	startIndex[2] = 0;

	PointType newOrigin;
	m_Image->TransformContinuousIndexToPhysicalPoint(startIndex, newOrigin);


	typename ImageType::Pointer patch = ImageType::New();
	patch->SetDirection(m_Image->GetDirection());
	patch->SetOrigin(newOrigin);
	patch->SetSpacing(m_Image->GetSpacing());
	
	typename ImageType::RegionType region;
	m_Size[2] = 1;
	region.SetSize(m_Size);
	
	patch->SetRegions(region);
	patch->Allocate();

	
	typedef itk::NearestNeighborInterpolateImageFunction<ImageType, double> InterpolatorType;
	typename InterpolatorType::Pointer interpolator = InterpolatorType::New();
	interpolator->SetInputImage(m_Image);


	itk::ImageRegionIterator<ImageType> imageIt(patch, region);
	while(!imageIt.IsAtEnd())
	{
		typename ImageType::IndexType index = imageIt.GetIndex();
		PointType point;
		patch->TransformIndexToPhysicalPoint(index, point);

		if(interpolator->IsInsideBuffer(point))
			imageIt.Set(interpolator->Evaluate(point));
		else
			imageIt.Set(0);
		++imageIt;
	}

	return patch;
	
}
void WorkbenchUtils::addPaddingItk(itk::Image <PixelType, ImageDimension> *itkImage, Axis axis, bool append,
                                   int numberOfSlices, float pixelValue, Image::Pointer outImage) {
    // pixel type is templated. The input field for the value is set to float, so the user might enter some invalid values for the image type at hand.
    // since all primitive built-in types have well defined casting behaviour between each other, we'll just do a typecast. we will clip the entered
    // value at PixelTypes min/max to prevent an overflow. The possible loss of precision is ignored.
    float lower = itk::NumericTraits<PixelType>::min();
    float upper = itk::NumericTraits<PixelType>::max();
    float clippedPixelValue = std::max(lower, std::min(pixelValue, upper));

    PixelType paddingPixelValue = (PixelType) clippedPixelValue;

    typedef itk::Image <PixelType, ImageDimension> ImageType;

    // gather all data
    typename ImageType::SizeType lowerBound;
    typename ImageType::SizeType upperBound;
    lowerBound.Fill(0);
    upperBound.Fill(0);

    unsigned int itkAxis = convertToItkAxis(axis);
    if (append) {
        upperBound[itkAxis] = numberOfSlices;
    } else {
        lowerBound[itkAxis] = numberOfSlices;
    }

    // setup the filter
    typedef itk::ConstantPadImageFilter <ImageType, ImageType> PadFilterType;
    typename PadFilterType::Pointer padFilter = PadFilterType::New();
    padFilter->SetInput(itkImage);
    padFilter->SetConstant(paddingPixelValue);
    padFilter->SetPadLowerBound(lowerBound);
    padFilter->SetPadUpperBound(upperBound);
    padFilter->UpdateLargestPossibleRegion();

    // Update the origin, since padding creates negative index that is lost when returned to MITK
    typename ImageType::Pointer paddedImage = padFilter->GetOutput();
    typename ImageType::RegionType paddedImageRegion = paddedImage->GetLargestPossibleRegion();
    typename ImageType::PointType origin;
    paddedImage->TransformIndexToPhysicalPoint(paddedImageRegion.GetIndex(), origin);
    paddedImage->SetOrigin(origin);

    // get the results and cast them back to mitk. return via out parameter.
    outImage->InitializeByItk(paddedImage.GetPointer());
    CastToMitkImage(paddedImage, outImage);
}