一些简单的图像读取与显示操作
读取图像
读取一组图像
读取一张图片很简单，直接reader->SetFileName(xx)就可以了。但实际中通常要读取一组三维图像的二维切片，就可以用如下三种方法
传入文件名数组
//生成图像序列的文件名数组
vtkSmartPointer<vtkStringArray> fileArray = vtkSmartPointer<vtkStringArray>::New();
char fileName[128];
for (int i = 1; i < 100; i++) {
sprintf(fileName, "../data/Head/head%03d.jpg", i);
vtkStdString fileStr(fileName);
fileArray->InsertNextValue(fileStr);
}
//读取JPG序列图像
vtkSmartPointer<vtkJPEGReader> reader = vtkSmartPointer<vtkJPEGReader>::New();
reader->SetFileNames(fileArray);
设置文件名类型
vtkSmartPointer<vtkJPEGReader> reader =
vtkSmartPointer<vtkJPEGReader>::New();
reader->SetFilePrefix("../data/Head/head");
reader->SetFilePattern("%s%03d.jpg");
//100张图片，255*255
reader->SetDataExtent(0, 255, 0, 255, 1, 100);
reader->Update();
vtkImageAppend进行拼接
vtkSmartPointer<vtkImageAppend> append = vtkSmartPointer<vtkImageAppend>::New();
//指定z轴为堆叠方向
append->SetAppendAxis(2);
auto reader =vtkSmartPointer<vtkJPEGReader>::New();
char fileName[128];
for (int i = 1; i < 21; i++) {
sprintf(fileName, "../data/Head/head%03d.jpg", i);
reader->SetFileName(fileName);
append->AddInputConnection(reader->GetOutputPort());
}
常见图像数据类
vtkImageData
vtkPolyData
vtkRectilinearGrid
vtkStructuredGrid
vtkUnstructuredGrid
图像的显示
vtkImageViewer2
比较适合三维图像的切片显示
auto reader = vtkSmartPointer<vtkMetaImageReader>::New();
//注意构建目录
reader->SetFileName("../res/brain.mhd");
//千万要加这一句
reader->Update();
auto imageViewer = vtkSmartPointer<vtkImageViewer2>::New();
imageViewer->SetInputConnection(reader->GetOutputPort());
auto renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
imageViewer->SetupInteractor(renderWindowInteractor);
//设定窗位和窗宽
imageViewer->SetColorLevel(500);
imageViewer->SetColorWindow(2000);
imageViewer->SetSlice(40);
//设定方向 2-xy
imageViewer->SetSliceOrientation(2);
imageViewer->Render();
renderWindowInteractor->Start();
窗位和窗宽是有关医学图像显示的概念，不同的组织适合不同的窗位和窗宽。窗宽窗位含义
vtkImageActor
比 vtkImageViewer2 更高端一点
auto reader = vtkSmartPointer<vtkMetaImageReader>::New();
reader->SetFileName("../res/brain.mhd");
reader->Update();
auto imgActor = vtkSmartPointer<vtkImageActor>::New();
imgActor->GetMapper()->SetInputConnection(reader->GetOutputPort());
auto renderer = vtkSmartPointer<vtkRenderer>::New();
renderer->AddActor(imgActor);
renderer->SetBackground(1.0, 1.0, 1.0);
auto renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
auto renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
auto style = vtkSmartPointer<vtkInteractorStyleImage>::New();
renderWindowInteractor->SetInteractorStyle(style);
renderWindowInteractor->SetRenderWindow(renderWindow);
renderWindow->Render();
renderWindowInteractor->Initialize();
renderWindowInteractor->Start();
接受的图像数据 VTKImageData 像素类型必须为 unsigned char，可以事先转化
图像融合
auto reader = vtkSmartPointer<vtkJPEGReader>::New();
reader->SetFileName("../res/lena-gray.jpg");
// reader->Update();
auto imageSource = vtkSmartPointer<vtkImageCanvasSource2D>::New();
imageSource->SetNumberOfScalarComponents(1);
imageSource->SetScalarTypeToUnsignedChar();
imageSource->SetExtent(0, 512, 0, 512, 0, 0);
imageSource->SetDrawColor(0.0);
imageSource->FillBox(0, 512, 0, 512);
imageSource->SetDrawColor(255.0);
imageSource->FillBox(100, 400, 100, 400);
// imageSource->Update();
auto imageBlend = vtkSmartPointer<vtkImageBlend>::New();
//这里需要注意
imageBlend->AddInputConnection(reader->GetOutputPort());
imageBlend->AddInputConnection(imageSource->GetOutputPort());
imageBlend->SetOpacity(0, 0.4);
imageBlend->SetOpacity(1, 0.6);
// imageBlend->Update();
auto actor = vtkSmartPointer<vtkImageActor>::New();
actor->GetMapper()->SetInputConnection(imageBlend->GetOutputPort());
auto render = vtkSmartPointer<vtkRenderer>::New();
auto window = vtkSmartPointer<vtkRenderWindow>::New();
auto interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
auto style = vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();
render->AddActor(actor);
window->AddRenderer(render);
interactor->SetRenderWindow(window);
window->Render();
interactor->Initialize();
interactor->Start();
文档信息
- 本文作者：wzx
- 本文链接：https://masterwangzx.com/2018/10/28/vtk-image-file/
- 版权声明：自由转载-非商用-非衍生-保持署名（创意共享3.0许可证）