[vtkusers] How to convert vtkImageCast back to vtkImageData

[Quentan Qi]

Hi David,

Thank you very much for your prompt reply. You solved this problem in seconds! I now understand the two different pipeline better.

Cheers,
Quentan

> On 13 Jun 2015, at 14:06, David Gobbi <david.gobbi at gmail.com> wrote:
> 
> Hi Quental,
> 
> The solution is as follows:
> 
>     cast.Update()
>     implicit_volume.SetVolume(cast.GetOutput()) 
> 
> The VTK pipeline recognizes two very distinct kinds of objects:
> 
> The vtkImageCast object is a vtk "algorithm" object (derived from vtkAlgorithm).
> The vtkImageData object is a vtk "data" object (derived from vtkDataObject).
> 
> An algorithm can never be data.  An algorithm _operates_ on data.
> So the algorithm's input is data, and its output is data.
> 
>  - David
> 
> 
> On Sat, Jun 13, 2015 at 6:36 AM, Quentan Qi <quentan at gmail.com <mailto:quentan at gmail.com>> wrote:
> Hi there,
> 
> After casting an image using vtkImageCast, it becomes a vtkImageCast object, but I want to use vtkImplicitVolume which requires vtkImageData type. How to convert vtkImageCast back to vtkImageData?
> 
> ```Python
> 
> reader = read_DICOM(path_dicom)  # result is a vtkImageData
> 
> cast = vtk.vtkImageCast()
> cast.SetInputData(reader)  # vtkImageData —> vtkImageCast
> cast.SetOutputScalarTypeToShort()  # I need this type
> 
> implicit_volume = vtk.vtkImplicitVolume()
> implicit_volume.SetVolume(reader)  # It works but I need “cast” instead
> # implicit_volume.SetVolume(cast)  # It’s wrong because vtkImageData is required, but a vtkImageCast was given
> # other things
> 
> ```
> 
> Thanks a lot!
> 
> Cheers,
> Quentan
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20150613/65235239/attachment.html>