[vtkusers] vtkImageThreshold, vtkExtractVOI

[Waltraud Henrich]

Hi,

I have a probleme.  I work whith Vtk and Qt for segmentation of CT and MR
images.  I read in a vtkImageData.
If I change the values of LowerThreshold and UpperThreshold
(vtkImageThreshold) with the aid of QSlider and afterwards I make
vtkExtractVOI , I get not all Slices.  
If I however  vtkExtractVOI and afterwards vtkImageThreshold use, I get  all
Slices.  I want to  only use vtkImageTheshold and afterwards vtkExtractVOI.
What can I make? 

Thanks,

Waltraut