VTK 实例39：拉普拉斯算子（边缘检测）

 1 #include "vtkAutoInit.h" 
 2 VTK_MODULE_INIT(vtkRenderingOpenGL2);
 3 VTK_MODULE_INIT(vtkInteractionStyle);
 4 
 5 #include <vtkSmartPointer.h>
 6 #include <vtkImageData.h>
 7 #include <vtkImageCanvasSource2D.h>
 8 #include <vtkImageShiftScale.h>
 9 #include <vtkRenderWindow.h>
10 #include <vtkRenderWindowInteractor.h>
11 #include <vtkInteractorStyleImage.h>
12 #include <vtkRenderer.h>
13 #include <vtkImageActor.h>
14 #include <vtkJPEGReader.h>
15 #include <vtkImageLaplacian.h>
16 
17 //测试图像：../data/lena-gray.jpg
18 int main(int argc, char* argv[])
19 {
20     vtkSmartPointer<vtkJPEGReader> reader =
21         vtkSmartPointer<vtkJPEGReader>::New();
22     reader->SetFileName("lena-gray.jpg");
23     reader->Update();
24 
25     vtkSmartPointer<vtkImageLaplacian> lapFilter =
26         vtkSmartPointer<vtkImageLaplacian>::New();
27     lapFilter->SetInputConnection(reader->GetOutputPort());
28     lapFilter->SetDimensionality(2);
29 
30     double range[2];
31     lapFilter->GetOutput()->GetScalarRange(range);
32 
33     vtkSmartPointer<vtkImageShiftScale> ShiftScale =
34         vtkSmartPointer<vtkImageShiftScale>::New();
35     ShiftScale->SetOutputScalarTypeToUnsignedChar();
36     ShiftScale->SetScale( 255 / (range[1]-range[0]) );
37     ShiftScale->SetShift(-range[0]);
38     ShiftScale->SetInputConnection(lapFilter->GetOutputPort());
39     ShiftScale->Update();
40 
41     vtkSmartPointer<vtkImageActor> originalActor =
42         vtkSmartPointer<vtkImageActor>::New();
43     originalActor->SetInputData(reader->GetOutput());
44 
45     vtkSmartPointer<vtkImageActor> gradActor =
46         vtkSmartPointer<vtkImageActor>::New();
47     gradActor->SetInputData(ShiftScale->GetOutput());
48 
49     double originalViewport[4] = {0.0, 0.0, 0.5, 1.0};
50     double gradviewport[4] = {0.5, 0.0, 1.0, 1.0};
51 
52     vtkSmartPointer<vtkRenderer> originalRenderer =
53         vtkSmartPointer<vtkRenderer>::New();
54     originalRenderer->SetViewport(originalViewport);
55     originalRenderer->AddActor(originalActor);
56     originalRenderer->ResetCamera();
57     originalRenderer->SetBackground(1.0, 1.0, 1.0);
58 
59     vtkSmartPointer<vtkRenderer> gradRenderer =
60         vtkSmartPointer<vtkRenderer>::New();
61     gradRenderer->SetViewport(gradviewport);
62     gradRenderer->AddActor(gradActor);
63     gradRenderer->ResetCamera();
64     gradRenderer->SetBackground(1.0, 1.0, 1.0);
65 
66     vtkSmartPointer<vtkRenderWindow> renderWindow =
67         vtkSmartPointer<vtkRenderWindow>::New();
68     renderWindow->AddRenderer(originalRenderer);
69     renderWindow->AddRenderer(gradRenderer);
70     renderWindow->SetSize(640, 320);
71     renderWindow->Render();
72     renderWindow->SetWindowName("LaplacianExample");
73 
74     vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
75         vtkSmartPointer<vtkRenderWindowInteractor>::New();
76     vtkSmartPointer<vtkInteractorStyleImage> style =
77         vtkSmartPointer<vtkInteractorStyleImage>::New();
78 
79     renderWindowInteractor->SetInteractorStyle(style);
80     renderWindowInteractor->SetRenderWindow(renderWindow);
81     renderWindowInteractor->Initialize();
82     renderWindowInteractor->Start();
83 
84     return EXIT_SUCCESS;
85 }