读入经过图像分割后的nii文件利用vtk库将其3d可视化编写python代码

可以参考以下代码：

import vtk
import nibabel as nib

# 读取nii文件
filename = "segmentation.nii"
nii_image = nib.load(filename)
data = nii_image.get_fdata()

# 创建vtk数据
vtk_data = vtk.vtkImageData()
vtk_data.SetDimensions(data.shape)
vtk_data.SetSpacing(nii_image.header.get_zooms())
vtk_data.AllocateScalars(vtk.VTK_UNSIGNED_CHAR, 1)
for i in range(data.shape[0]):
    for j in range(data.shape[1]):
        for k in range(data.shape[2]):
            vtk_data.SetScalarComponentFromDouble(i, j, k, 0, data[i,j,k])

# 创建vtk可视化窗口
renderer = vtk.vtkRenderer()
render_window = vtk.vtkRenderWindow()
render_window.AddRenderer(renderer)
render_window_interactor = vtk.vtkRenderWindowInteractor()
render_window_interactor.SetRenderWindow(render_window)

# 创建vtk可视化对象
volume_mapper = vtk.vtkSmartVolumeMapper()
if vtk.VTK_MAJOR_VERSION <= 5:
    volume_mapper.SetInput(vtk_data)
else:
    volume_mapper.SetInputData(vtk_data)
volume_property = vtk.vtkVolumeProperty()
volume = vtk.vtkVolume()
volume.SetMapper(volume_mapper)
volume.SetProperty(volume_property)

# 添加vtk可视化对象到窗口
renderer.AddVolume(volume)
renderer.ResetCamera()

# 显示可视化窗口
render_window.Render()
render_window_interactor.Start()

需要安装的依赖包：

- vtk
- nibabel

注意：读取的nii文件需要经过图像分割处理，且为单通道灰度图像。