用VTK和Python可视化,形成半规则模式

2024-05-13 23:07:21 发布

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嗨,提前谢谢你抽出时间。在

我目前正在创建一个软件包,它将允许用户可视化导入的数据。我当前使用的数据是一个.txt文件,其尺寸为120列乘24320行。我正在导入并转换为尺寸为120x128x190的三维网格。然后我将这些数据与阈值进行比较,并将值1分配给值大于阈值的任何单元格。这一切都很好,我甚至手动检查了数据保存和交叉检查它与txt文件,它是正确的,但是我不能让可视化工作正常,而不是输出一个心形,它给出了一个非常规则的网格状图案(见http://img855.imageshack.us/img855/4944/vtk.png)。我真的拼命想让这个工作,所以任何帮助将不胜感激。我当前使用的代码是:

import vtk
from vtk.util import vtkImageImportFromArray
from numpy import *

#intensity threshold 900000

# import the data
# read files
intensityI=[]

print("Reading files...")

in_file = open("intensity.txt", "rt")
for line in in_file.readlines():
    intensityI.append([])
    for i in line.split():
        intensityI[-1].append(float(i))
in_file.close()

print("...done")

#set parameters specific to data
nx = 119
ny = 127
nz = 189
sizex=nx+1
sizey=ny+1
sizez=nz+1
threshold = 900000

#convert to array
I = zeros((sizez, sizex, sizey))
It = zeros((sizez, sizex, sizey), dtype=uint8)

print("converting to 3D array...")
z=0
while z<sizez:
    x=0
    while x<sizex:
        y=0
        while y<sizey:
            I[z][x][y] = int(intensityI[(z*128)+y][x])
            #print(I[z][x][y])
            #print(int(intensityI[(z*128)+y][x]))
            if I[z][x][y] > threshold:
                It[z][x][y] = 1
            y += 1
        x += 1
    z += 1

print("...done")

print("converting to string...")

# I now contains raw intensity information
# It contains thesholded intensity

dataImporter = vtk.vtkImageImport()
data_string = It.tostring()
dataImporter.CopyImportVoidPointer(data_string, len(data_string))
dataImporter.SetDataScalarTypeToUnsignedChar()
dataImporter.SetNumberOfScalarComponents(1)
dataImporter.SetDataExtent(0, nz, 0, ny, 0, nx)
dataImporter.SetWholeExtent(0, nz, 0, ny, 0, nx)

print("...done")
print("drawing...")

alphaChannelFunc = vtk.vtkPiecewiseFunction()
alphaChannelFunc.AddPoint(1, 0.05)
alphaChannelFunc.AddPoint(0, 0.0)

colorFunc = vtk.vtkColorTransferFunction()
colorFunc.AddRGBPoint(1, 1.0, 0.0, 0.0)
#colorFunc.AddRGBPoint(0, 0.0, 1.0, 0.0)

volumeProperty = vtk.vtkVolumeProperty()
volumeProperty.SetColor(colorFunc)
volumeProperty.SetScalarOpacity(alphaChannelFunc)

compositeFunction = vtk.vtkVolumeRayCastCompositeFunction()
volumeMapper = vtk.vtkVolumeRayCastMapper()
volumeMapper.SetVolumeRayCastFunction(compositeFunction)
volumeMapper.SetInputConnection(dataImporter.GetOutputPort())

volume = vtk.vtkVolume()
volume.SetMapper(volumeMapper)
volume.SetProperty(volumeProperty)

renderer = vtk.vtkRenderer()
renderWin = vtk.vtkRenderWindow()
renderWin.AddRenderer(renderer)
renderInteractor = vtk.vtkRenderWindowInteractor()
renderInteractor.SetRenderWindow(renderWin)

renderer.AddVolume(volume)
renderer.SetBackground(0,0,0)
renderWin.SetSize(400, 400)

def exitCheck(obj, event):
    if obj.GetEventPending() != 0:
        obj.SetAbortRender(1)

renderWin.AddObserver("AbortCheckEvent", exitCheck)

renderInteractor.Initialize()
renderWin.Render()
renderInteractor.Start()     
print("...done")

我假设这个问题是由于我使用numpy数组引起的,所以我尝试使用vtkStructuredPoints,但是如果我试图将1写入vtkStructuredPoints数组,则会出现以下错误:TypeError:'vtkobject'对象在It[z][x][y] = 1行上不可订阅,因此我不确定该错误消息意味着什么。在

我用来创建vtkStructuredPoints数组的代码是

^{pr2}$

非常感谢您提供的任何帮助或建议。在

约翰


Tags: to数据inimportdataitprintnx