python VTK（十五） ----图像平滑 均值滤波 高斯平滑 中值滤波 各向异性滤波

均值滤波vtkImageConvolve

#!/usr/bin/env python
# -*- coding:utf-8 -*-
import vtk
reader = vtk.vtkJPEGReader()   # 读入灰度图
reader.SetFileName(r'E:\lena-gray.jpg')
reader.Update()

originalCastFilter = vtk.vtkImageCast()  # 将图像像素类型由unsigned char转换成float数据类型
originalCastFilter.SetInputConnection(reader.GetOutputPort())
originalCastFilter.SetOutputScalarTypeToFloat()
originalCastFilter.Update()

convolveFilter = vtk.vtkImageConvolve()
'''
实现图像的卷积运算，需要两个输入，一个是需要进行卷积的图像，这里为vtkJPEGReader读取的图像数据
另一个是卷积模板数据
'''
convolveFilter.SetInputConnection(originalCastFilter.GetOutputPort())

kernel = [0.04,0.04,0.04,0.04,0.04,
		  0.04,0.04,0.04,0.04,0.04,
		  0.04,0.04,0.04,0.04,0.04,
		  0.04,0.04,0.04,0.04,0.04,
		  0.04,0.04,0.04,0.04,0.04]
convolveFilter.SetKernel5x5(kernel)  # 接收一个5*5的卷积模板数组
convolveFilter.Update()

convCastFilter = vtk.vtkImageCast()  # 卷积运算完成后，在此将float数据转换为unsigned char数据类型进行图像显示
convCastFilter.SetInputData(convolveFilter.GetOutput())
convCastFilter.Update()

originalActor = vtk.vtkImageActor()
originalActor.SetInputData(reader.GetOutput())
convolvedActor = vtk.vtkImageActor()
convolvedActor.SetInputData(convCastFilter.GetOutput())

leftViewport = [0.0, 0.0, 0.5, 1.0]
rightViewport = [0.5, 0.0, 1.0, 1.0]

originalRenderer = vtk.vtkRenderer()
originalRenderer.SetViewport(leftViewport)
originalRenderer.AddActor(originalActor)
originalRenderer.ResetCamera()
originalRenderer.SetBackground(1.0, 1.0, 1.0)

convolvedRenderer = vtk.vtkRenderer()
convolvedRenderer.SetViewport(rightViewport)
convolvedRenderer.AddActor(convolvedActor)
convolvedRenderer.ResetCamera()
convolvedRenderer.SetBackground(1.0, 1.0, 1.0)

renderWindow = vtk.vtkRenderWindow()
renderWindow.AddRenderer(originalRenderer)
renderWindow.AddRenderer(convolvedRenderer)
renderWindow.Render()
renderWindow.SetSize(900, 300)
renderWindow.SetWindowName('MeanFilterExample')

renderWindowInteractor = vtk.vtkRenderWindowInteractor()
style = vtk.vtkInteractorStyleImage()
renderWindowInteractor.SetInteractorStyle(style)
renderWindowInteractor.SetRenderWindow(renderWindow)
renderWindowInteractor.Initialize()
renderWindowInteractor.Start()

高斯平滑vtkImageGaussianSmooth

#!/usr/bin/env python 
# -*- coding:utf-8 -*-
import vtk
reader = vtk.vtkJPEGReader()   # 读入灰度图
reader.SetFileName(r'E:\lena-gray.jpg')
reader.Update()

gaussianSmoothFilter = vtk.vtkImageGaussianSmooth()   # 默认是执行三维高斯滤波
gaussianSmoothFilter.SetInputConnection(reader.GetOutputPort())
gaussianSmoothFilter.SetDimensionality(2)   # 根据需要设置相应的维数
gaussianSmoothFilter.SetRadiusFactor(5)     # 设置高斯模板的大小，当超出该模板的范围时，系数取0
gaussianSmoothFilter.SetStandardDeviation(3)  # 用于设置高斯分布函数的标准差
gaussianSmoothFilter.Update()

originalActor = vtk.vtkImageActor()
originalActor.SetInputData(reader.GetOutput())
smoothedActor = vtk.vtkImageActor()
smoothedActor.SetInputData(gaussianSmoothFilter.GetOutput())

originalViewport = [0.0, 0.0, 0.5, 1.0]
smoothedViewport = [0.5, 0.0, 1.0, 1.0]

originalRenderer = vtk.vtkRenderer()
originalRenderer.SetViewport(originalViewport)
originalRenderer.AddActor(originalActor)
originalRenderer.ResetCamera()
originalRenderer.SetBackground(1.0, 1.0, 1.0)

smoothedRenderer = vtk.vtkRenderer()
smoothedRenderer.SetViewport(smoothedViewport)
smoothedRenderer.AddActor(smoothedActor)
smoothedRenderer.ResetCamera()
smoothedRenderer.SetBackground(1.0, 1.0, 1.0)

renderWindow = vtk.vtkRenderWindow()
renderWindow.AddRenderer(originalRenderer)
renderWindow.AddRenderer(smoothedRenderer)
renderWindow.Render()
renderWindow.SetSize(900, 300)
renderWindow.SetWindowName('GaussianFilterExample')

renderWindowInteractor = vtk.vtkRenderWindowInteractor()
style = vtk.vtkInteractorStyleImage()
renderWindowInteractor.SetInteractorStyle(style)
renderWindowInteractor.SetRenderWindow(renderWindow)
renderWindowInteractor.Initialize()
renderWindowInteractor.Start()

中值滤波vtkImageHybridMedian2D

#!/usr/bin/env python 
# -*- coding:utf-8 -*-
import vtk
reader = vtk.vtkJPEGReader()   # 读入灰度图
reader.SetFileName(r'E:\lena-noise.jpg')
reader.Update()

hybridMedian = vtk.vtkImageHybridMedian2D()  #不需要用户设置任何参数，该方法能够有效保持图像边缘，并对椒盐噪声有较好的抑制作用
hybridMedian.SetInputData(reader.GetOutput())
hybridMedian.Update()

originalActor = vtk.vtkImageActor()
originalActor.SetInputData(reader.GetOutput())
hybridMedianActor = vtk.vtkImageActor()
hybridMedianActor.SetInputData(hybridMedian.GetOutput())

originalViewport = [0.0, 0.0, 0.5, 1.0]
hybridMedianViewport = [0.5, 0.0, 1.0, 1.0]

originalRenderer = vtk.vtkRenderer()
originalRenderer.SetViewport(originalViewport)
originalRenderer.AddActor(originalActor)
originalRenderer.ResetCamera()
originalRenderer.SetBackground(1.0, 1.0, 1.0)

hybridMedianRenderer = vtk.vtkRenderer()
hybridMedianRenderer.SetViewport(hybridMedianViewport)
hybridMedianRenderer.AddActor(hybridMedianActor)
hybridMedianRenderer.ResetCamera()
hybridMedianRenderer.SetBackground(1.0, 1.0, 1.0)

renderWindow = vtk.vtkRenderWindow()
renderWindow.AddRenderer(originalRenderer)
renderWindow.AddRenderer(hybridMedianRenderer)
renderWindow.Render()
renderWindow.SetSize(900, 300)
renderWindow.SetWindowName('MedianFilterExample')

renderWindowInteractor = vtk.vtkRenderWindowInteractor()
style = vtk.vtkInteractorStyleImage()
renderWindowInteractor.SetInteractorStyle(style)
renderWindowInteractor.SetRenderWindow(renderWindow)
renderWindowInteractor.Initialize()
renderWindowInteractor.Start()

各向异性滤波vtkImageAnisotropicDiffusion2D

#!/usr/bin/env python 
# -*- coding:utf-8 -*-
import vtk
reader = vtk.vtkJPEGReader()   # 读入灰度图
reader.SetFileName(r'E:\lena-gray.jpg')
reader.Update()

diffusion = vtk.vtkImageAnisotropicDiffusion2D()
diffusion.SetInputConnection(reader.GetOutputPort())
diffusion.SetNumberOfIterations(10)   # 设置迭代的次数
'''
各向异性扩散过滤原理是在梯度较小的像素处进行较大幅度扩散，而在大梯度处则只进行细微的扩散
'''
diffusion.SetDiffusionThreshold(20)  # 只有当像素梯度小于该阈值20时才会进行扩散
diffusion.Update()

originalActor = vtk.vtkImageActor()
originalActor.SetInputData(reader.GetOutput())
diffusionActor = vtk.vtkImageActor()
diffusionActor.SetInputData(diffusion.GetOutput())

originalViewport = [0.0, 0.0, 0.5, 1.0]
diffusionViewport = [0.5, 0.0, 1.0, 1.0]

originalRenderer = vtk.vtkRenderer()
originalRenderer.SetViewport(originalViewport)
originalRenderer.AddActor(originalActor)
originalRenderer.ResetCamera()
originalRenderer.SetBackground(1.0, 1.0, 1.0)

diffusionRenderer = vtk.vtkRenderer()
diffusionRenderer.SetViewport(diffusionViewport)
diffusionRenderer.AddActor(diffusionActor)
diffusionRenderer.ResetCamera()
diffusionRenderer.SetBackground(1.0, 1.0, 1.0)

renderWindow = vtk.vtkRenderWindow()
renderWindow.AddRenderer(originalRenderer)
renderWindow.AddRenderer(diffusionRenderer)
renderWindow.Render()
renderWindow.SetSize(900, 300)
renderWindow.SetWindowName('AnistropicFilteringExample')

renderWindowInteractor = vtk.vtkRenderWindowInteractor()
style = vtk.vtkInteractorStyleImage()
renderWindowInteractor.SetInteractorStyle(style)
renderWindowInteractor.SetRenderWindow(renderWindow)
renderWindowInteractor.Initialize()
renderWindowInteractor.Start()