VTK提供了vtkDICOMImageReader類來讀取DICOM檔案，但沒有提供DICOM影象的寫操作，即沒有提供vtkDICOMImageWriter類，ITK提供了對DICOM檔案的完整操作，我們可以結合ITK來實現DICOM檔案完整的讀寫操作。

vtkDICOMImageReader類使用也比較簡單，讀取單幀DICOM影象和其他影象讀取類的使用方法類似，我們這裡重點關注一下多幀DICOM影象的讀取，即讀取一個資料夾中所有的DICOM檔案進行顯示。

#include <vtkSmartPointer.h>
#include <vtkObjectFactory.h>
 

#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkActor.h>
#include <vtkImageViewer2.h>
#include <vtkDICOMImageReader.h>
#include <vtkInteractorStyleImage.h>
#include <vtkActor2D.h>
#include <vtkTextProperty.h>
 

#include <vtkTextMapper.h>
#include <sstream>
#include <iostream>
using namespace std;

class  StatusMessage
{
public:
    static std::string Format(int slice, int maxSlice)
    {
        std::stringstream tmp;
        tmp << "Slice Number " << slice + 1 << "/" << maxSlice + 1
 
;
        return tmp.str();
    }

};

class myvtkInteractorStyleImage: public vtkInteractorStyleImage
{
public:
    static myvtkInteractorStyleImage* New();
    vtkTypeMacro(myvtkInteractorStyleImage, vtkInteractorStyleImage);

protected:
    vtkImageViewer2* _ImageViewer;
    vtkTextMapper* _StatusMapper;
    int _Slice;
    int _MinSlice;
    int _MaxSlice;

public:
    void SetImageViewer(vtkImageViewer2* imageViewer) {
        _ImageViewer = imageViewer;
        _MinSlice = imageViewer->GetSliceMin();
        _MaxSlice = imageViewer->GetSliceMax();
        _Slice = _MinSlice;
        cout << "Slice: Min = " << _MinSlice << ", Max = " << _MaxSlice << endl;
    }

    void SetStatusMapper(vtkTextMapper* statusMapper)
    {
        _StatusMapper = statusMapper;
    }

protected:
    void MoveSliceForward()
    {
        if (_Slice < _MaxSlice)
        {
            _Slice += 1;
            cout << "MoveSliceForward::Slice = " << _Slice << endl;
            _ImageViewer->SetSlice(_Slice);
            std::string msg = StatusMessage::Format(_Slice, _MaxSlice);
            _StatusMapper->SetInput(msg.c_str());
            _ImageViewer->Render();
        }
    }

    void MoveSliceBackward()
    {
        if (_Slice > _MinSlice)
        {
            _Slice -= 1;
            cout << "MoveSliceBackward::Slice = " << _Slice << endl;
            _ImageViewer->SetSlice(_Slice);
            std::string msg = StatusMessage::Format(_Slice, _MaxSlice);
            _StatusMapper->SetInput(msg.c_str());
            _ImageViewer->Render();
        }
    }

    virtual void OnKeyDown()
    {
        std::string key = this->GetInteractor()->GetKeySym();
        if (key.compare("Up") == 0)
            MoveSliceForward();
        else if (key.compare("Down")==0)
        {
            MoveSliceBackward();
        }

        vtkInteractorStyleImage::OnKeyDown();
    }

    virtual void OnMouseWheelForward()
    {
        MoveSliceForward();
    }

    virtual void OnMouseWheelBackward()
    {
        if (_Slice > _MinSlice)
            MoveSliceBackward();
    }
};

vtkStandardNewMacro(myvtkInteractorStyleImage);

int main(int argc, char* argv[])
{
    std::string folder = "G:\\Dicom\\Dicom File\\dcmFile";
    vtkSmartPointer<vtkDICOMImageReader> reader = vtkSmartPointer<vtkDICOMImageReader>::New();
    reader->SetDirectoryName(folder.c_str());
    reader->Update();

    vtkSmartPointer<vtkImageViewer2> imageViewer = vtkSmartPointer<vtkImageViewer2>::New();
    imageViewer->SetInputConnection(reader->GetOutputPort());

    vtkSmartPointer<vtkTextProperty> sliceTextProp = vtkSmartPointer<vtkTextProperty>::New();
    sliceTextProp->SetFontFamilyToCourier();
    sliceTextProp->SetFontSize(20);
    sliceTextProp->SetVerticalJustificationToBottom();
    sliceTextProp->SetJustificationToLeft();

    vtkSmartPointer<vtkTextMapper> sliceTextMapper = vtkSmartPointer<vtkTextMapper>::New();
    std::string msg = StatusMessage::Format(imageViewer->GetSliceMin(), imageViewer->GetSliceMax());
    sliceTextMapper->SetInput(msg.c_str());
    sliceTextMapper->SetTextProperty(sliceTextProp);

    vtkSmartPointer<vtkActor2D> sliceTextActor = vtkSmartPointer<vtkActor2D>::New();
    sliceTextActor->SetMapper(sliceTextMapper);
    sliceTextActor->SetPosition(15, 10);

    vtkSmartPointer<vtkTextProperty> usageTextProp = vtkSmartPointer<vtkTextProperty>::New();
    usageTextProp->SetFontFamilyToCourier();
    usageTextProp->SetFontSize(14);
    usageTextProp->SetVerticalJustificationToTop();
    usageTextProp->SetJustificationToLeft();

    vtkSmartPointer<vtkTextMapper> usageTextMapper = vtkSmartPointer<vtkTextMapper>::New();
    usageTextMapper->SetInput("- Slice with mouse wheel\n  or Up/Down-Key\n- Zoom with pressed right\n  mouse button while dragging");
    usageTextMapper->SetTextProperty(usageTextProp);

    vtkSmartPointer<vtkActor2D> usageTextActor = vtkSmartPointer<vtkActor2D>::New();
    usageTextActor->SetMapper(usageTextMapper);
    usageTextActor->GetPositionCoordinate()->SetCoordinateSystemToNormalizedDisplay();
    usageTextActor->GetPositionCoordinate()->SetValue(0.05, 0.95);

    vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();

    vtkSmartPointer<myvtkInteractorStyleImage> myInteractorStyle =
        vtkSmartPointer<myvtkInteractorStyleImage>::New();

    myInteractorStyle->SetImageViewer(imageViewer);
    myInteractorStyle->SetStatusMapper(sliceTextMapper);

    imageViewer->SetupInteractor(renderWindowInteractor);
    renderWindowInteractor->SetInteractorStyle(myInteractorStyle);

    imageViewer->GetRenderer()->AddActor2D(sliceTextActor);
    imageViewer->GetRenderer()->AddActor2D(usageTextActor);

    imageViewer->GetRenderWindow()->SetSize(800, 600);
    imageViewer->SetColorLevel(100);
    imageViewer->SetColorWindow(2000);
    imageViewer->Render();
    imageViewer->GetRenderer()->ResetCamera();

    renderWindowInteractor->Start();

    return EXIT_SUCCESS;
}