VTK 实例22：JPG图像信息的访问（图像维数、原点坐标和像素间隔）

#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);

#include <vtkSmartPointer.h>
#include <vtkImageViewer2.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkImageReader2Factory.h>
#include <vtkImageReader2.h>
#include <vtkJPEGReader.h>//JPEG图像读取类
#include <vtkImageData.h>

//测试图像：../data/lena.jpg
int main(int argc, char* argv[])
{
    //实例化一个对象dcmReader
    vtkJPEGReader* reader = vtkJPEGReader::New();
    reader->SetFileName("lena.jpg");//读取图像

    reader->Update();

    int dims[3];
    reader->GetOutput()->GetDimensions(dims);
    std::cout << "图像维数:" << dims[0] << " " << dims[1] << " " << dims[2] << std::endl;

    double origin[3];
    reader->GetOutput()->GetOrigin(origin);
    std::cout << "图像原点:" << origin[0] << " " << origin[1] << " " << origin[2] << std::endl;

    double spaceing[3];
    reader->GetOutput()->GetSpacing(spaceing);
    std::cout << "像素间隔:" << spaceing[0] << " " << spaceing[1] << " " << spaceing[2] << std::endl;

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

    vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
    imageViewer->SetupInteractor(renderWindowInteractor);
    imageViewer->Render();
    imageViewer->GetRenderer()->ResetCamera();
    imageViewer->Render();

    imageViewer->GetRenderer()->SetBackground(1.0, 1.0, 1.0);
    imageViewer->SetSize(640, 480);
    imageViewer->GetRenderWindow()->SetWindowName("GetImageInformationExample");

    renderWindowInteractor->Start();

    return 0;
}