# Reading a .Nrrd file having 3 dimenisions (X,Y,numSlice) and visualizing them in a sequence.
**URL:** https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179
**Category:** Beginner Questions
**Created:** [June 3, 2021, 9:50pm UTC](https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179 "2021-06-03T21:50:53Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@srivastava.va](https://discourse.itk.org/u/srivastava.va)
#### Post date: [June 3, 2021, 9:50pm UTC](https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179/1 "2021-06-03T21:50:53Z")
Hello, I am just beginning to write code using ITK and have been wondering how to read .Nrrd files. So far I have written this code :
1. I am not sure how to visualize the 2D slice data that I have stored in the img.
2. Is there a simpler way to read .nrrd files and visualize them ?
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [June 3, 2021, 10:04pm UTC](https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179/2 "2021-06-03T22:04:59Z")
You seem to have correctly read the image. ITK does not do visualization, just reading/processing/writing. For a quick check, you could do `std::cout<
### Author:  [@srivastava.va](https://discourse.itk.org/u/srivastava.va)
#### Post date: [June 4, 2021, 1:42pm UTC](https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179/3 "2021-06-04T13:42:29Z")
Thank you for the prompt response, Dzenanz. On another note is it possible to utilize VTK for visualization of these files ? I came across the class vtkNrrdReader, but unfortunately I couldn’t find any examples.
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [June 4, 2021, 1:55pm UTC](https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179/4 "2021-06-04T13:55:44Z")
Yes, VTK is frequently used to visualize images and other things. Both ITK-SNAP and 3D Slicer use VTK for visualization. Here are some [examples](https://kitware.github.io/vtk-examples/site/Cxx/#volume-rendering).
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### Author:  [@srivastava.va](https://discourse.itk.org/u/srivastava.va)
#### Post date: [June 10, 2021, 4:18pm UTC](https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179/5 "2021-06-10T16:18:47Z")
Thanks Dzenan for your help, meanwhile I was able to write a program to visualize the .nrrd files. But I am getting the following error when I try to build it :
|Error|C2440|‘function-style-cast’: cannot convert from ‘initializer list’ to ‘vtkSmartPointervtkImageMapper3D’
I have attached the file along.
[HelloInsight.cpp](https://discourse.itk.org/uploads/short-url/dcmpEEKAHNllsLH5gYfxIEfgz8n.cpp) (5.1 KB)
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### Author:  [@srivastava.va](https://discourse.itk.org/u/srivastava.va)
#### Post date: [June 10, 2021, 5:20pm UTC](https://discourse.itk.org/t/reading-a-nrrd-file-having-3-dimenisions-x-y-numslice-and-visualizing-them-in-a-sequence/4179/6 "2021-06-10T17:20:27Z")
I was able to solve the problem by replacing `actor->GetMapper->SetInputConnection(color->GetOutputPort())`. Anyway, thank you for your help.