ITK  4.13.0
Insight Segmentation and Registration Toolkit
WikiExamples/ImageProcessing/ImageAdaptorExtractVectorComponent.cxx
typedef itk::Image<float, 2> ScalarImageType;
typedef itk::Image<itk::CovariantVector< float, 3>, 2> VectorImageType;
static void CreateImage(VectorImageType::Pointer image);
class VectorPixelAccessor
{
public:
typedef itk::CovariantVector<float,3> InternalType;
typedef float ExternalType;
void operator=( const VectorPixelAccessor & vpa )
{
m_Index = vpa.m_Index;
}
ExternalType Get( const InternalType & input ) const
{
return static_cast<ExternalType>( input[ m_Index ] );
}
void SetIndex( unsigned int index )
{
m_Index = index;
}
private:
unsigned int m_Index;
};
int main(int, char *[])
{
VectorImageType::Pointer image = VectorImageType::New();
CreateImage(image);
index.Fill(0);
std::cout << image->GetPixel(index) << std::endl;
typedef itk::ImageAdaptor< VectorImageType,
VectorPixelAccessor > ImageAdaptorType;
ImageAdaptorType::Pointer adaptor = ImageAdaptorType::New();
VectorPixelAccessor accessor;
accessor.SetIndex(0);
adaptor->SetPixelAccessor( accessor );
adaptor->SetImage(image);
std::cout << adaptor->GetPixel(index) << std::endl;
return EXIT_SUCCESS;
}
void CreateImage(VectorImageType::Pointer image)
{
start.Fill(0);
size.Fill(2);
VectorImageType::RegionType region;
region.SetSize(size);
region.SetIndex(start);
image->SetRegions(region);
image->Allocate();
itk::ImageRegionIterator<VectorImageType> imageIterator(image,image->GetLargestPossibleRegion());
vec[0] = 1;
vec[1] = 2;
vec[2] = 3;
while(!imageIterator.IsAtEnd())
{
imageIterator.Set(vec);
++imageIterator;
}
}