VTK_Learning_灰度图像映射成伪彩色图像（查表法）

浅浅的花香味﹌ 2023-07-07 05:54 3阅读 0赞

# 1.查表法伪彩图映射 #

> 图像彩色映射的原理是首先生成一个颜色查找表，然后根据图像的一个标量值向颜色查找表中查找对应的颜色，并用新颜色值替代原来的像素值。VTK中vtkImageMapToColors负责图像彩色映射，vtkLookUpTable负责生成颜色查找表。
> 
> 下面代码说明了怎样进行彩色映射：
> 
>     #include <vtkAutoInit.h>
>     VTK_MODULE_INIT(vtkRenderingOpenGL);
>      
>     #include <vtkSmartPointer.h>
>     #include <vtkJPEGReader.h>
>     #include <vtkLookupTable.h>
>     #include <vtkImageMapToColors.h>
>     #include <vtkImageActor.h>
>     #include <vtkRenderer.h>
>     #include <vtkRenderWindow.h>
>     #include <vtkRenderWindowInteractor.h>
>     #include <vtkInteractorStyleImage.h>
>     int main()
>     {
>     	vtkSmartPointer<vtkJPEGReader> reader =
>     		vtkSmartPointer<vtkJPEGReader>::New();
>     	reader->SetFileName("lena-gray.jpg");
>     	//建立颜色映射查找表
>     	vtkSmartPointer<vtkLookupTable> colorTable =
>     		vtkSmartPointer<vtkLookupTable>::New();
>     	colorTable->SetRange(0.0, 255.0);
>     	colorTable->SetHueRange(0.1, 0.5);
>     	colorTable->SetValueRange(0.6, 1.0);
>     	colorTable->Build();
>     	//建立颜色映射
>     	vtkSmartPointer<vtkImageMapToColors> colorMap =
>     		vtkSmartPointer<vtkImageMapToColors>::New();
>     	colorMap->SetInputConnection(reader->GetOutputPort());
>     	colorMap->SetLookupTable(colorTable);
>     	colorMap->Update();
>     	//建立演员
>     	vtkSmartPointer<vtkImageActor> origActor =
>     		vtkSmartPointer<vtkImageActor>::New();
>     	origActor->SetInputData(reader->GetOutput());
>      
>     	vtkSmartPointer<vtkImageActor> colorActor =
>     		vtkSmartPointer<vtkImageActor>::New();
>     	colorActor->SetInputData(colorMap->GetOutput());
>     	//化妆
>     	double origView[4] = { 0.0, 0.0, 0.5, 1.0 };
>     	double colorView[4] = { 0.5, 0.0, 1.0, 1.0 };
>     	vtkSmartPointer<vtkRenderer> origRender =
>     		vtkSmartPointer<vtkRenderer>::New();
>     	origRender->SetViewport(origView);
>     	origRender->AddActor(origActor);
>     	origRender->ResetCamera();
>     	origRender->SetBackground(1.0, 0.0, 0.0);
>      
>     	vtkSmartPointer<vtkRenderer> colorRender =
>     		vtkSmartPointer<vtkRenderer>::New();
>     	colorRender->SetViewport(colorView);
>     	colorRender->AddActor(colorActor);
>     	colorRender->ResetCamera();
>     	colorRender->SetBackground(0.0, 0.0, 0.0);
>     	//舞台
>     	vtkSmartPointer<vtkRenderWindow> renderwindow =
>     		vtkSmartPointer<vtkRenderWindow>::New();
>     	renderwindow->AddRenderer(origRender);
>     	renderwindow->AddRenderer(colorRender);
>     	renderwindow->SetSize(640, 320);
>     	renderwindow->SetWindowName("GrayToColor");
>     	//设置交互
>     	vtkSmartPointer<vtkRenderWindowInteractor> rwi =
>     		vtkSmartPointer<vtkRenderWindowInteractor>::New();
>     	vtkSmartPointer<vtkInteractorStyleImage> style =
>     		vtkSmartPointer<vtkInteractorStyleImage>::New();
>     	rwi->SetInteractorStyle(style);
>     	rwi->SetRenderWindow(renderwindow);
>     	rwi->Initialize();
>      
>     	rwi->Start();
>     	return 0;
>     }
> 
> ![20170123224217236][]

[20170123224217236]: https://img-blog.csdn.net/20170123224217236