# Threshold from vtk image data

**URL:** https://discourse.vtk.org/t/threshold-from-vtk-image-data/8126
**Category:** Support
**Created:** [March 23, 2022, 6:24pm UTC](https://discourse.vtk.org/t/threshold-from-vtk-image-data/8126 "2022-03-23T18:24:50Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Nige\_Terminator](https://discourse.vtk.org/user_avatar/discourse.vtk.org/nige_terminator/32/4876_2.png) [@Nige\_Terminator](https://discourse.vtk.org/u/Nige_Terminator)
#### Post date: [March 23, 2022, 6:24pm UTC](https://discourse.vtk.org/t/threshold-from-vtk-image-data/8126/1 "2022-03-23T18:24:50Z")

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I everyone I just approach vtk in python for my master thesis  
I import a file.nii.gz from segmentation obtain through mri. Then I read it through vtkNIFTIImageReader and with get output I obtain a Vtk image data file  
Now I have to use Vtk image threshold so to neglect the zero value voxels. How can I get the non zero value of the other voxel? I just cannot analyze vtk image data file