vtkImageExtractComponents to vtkDICOMReader

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1

I have loaded a DICOM series into a vtkDICOMReader, and to represent the data into a vtkVolume, I transfer it vtkDICOMReader into a vtkImageExtractComponents. On this vtkImageExtractComponents object I have done some segmentation. Now, I want to transfer data back from vtkImageExtractComponents to vtkDICOMReader, in order to export it as DICOM series. Is there possible this ? If it is, how to transfer data from vtkImageExtractComponents to vtkDICOMReader ?

2

I think vtkDICOMReader accept files as input only… but what if I want to load a vtkImageData ?

I have found on vtkImageExtractComponents a method: m_pImageExtractor->GetImageDataInput(0)

which return a vtkImageData … but how can I load this vtkImageData into vtkDICOMReader ?

3

I have tried:

vtkDICOMReader* pDICOMReader = vtkDICOMReader::New();
vtkImageData* pImageData = m_pImageExtractor->GetImageDataInput(0);

pDICOMReader->GetOutput()->CopyStructure(pImageData);
pDICOMReader->GetOutput()->GetPointData()->PassData(pImageData->GetPointData());

but I got:

> ERROR: In D:\VTK\vtk-dicom-master\Source\vtkDICOMReader.cxx, line 2403
> vtkDICOMReader (0000016D942CACE0): ERROR: In D:\VTK\vtk-dicom-master\Source\vtkDICOMParser.cxx, line 1903
> vtkDICOMParser (0000016D943D14B0): ReadFile: Can't open the file .0

Obviously I have done something wrong, but what ?

4

You cannot take data out of a reader, modify it, and then put it back into the reader. VTK doesn’t work like that.

5

Then I guess I get in the trouble. I have read DICOM CBCT series with excellent class vtkDICOMReader. In order to visualize this data as vtkVolume, I put this vtkDICOMReader into a vtkImageExtractComponents, just like that:

// use m_pImageExtractor for volume because the series could have more components inside
m_pImageExtractor->SetInputConnection(m_pDICOMReader->GetOutputPort());
m_pImageExtractor->SetComponents(0);
m_pImageExtractor->Update();

Then, I exported this m_pImageExtractor into a vtkImageExport on ITK (SimpleITK), made some segmentation, and put back data into m_pImageExtractor through vtkImageImport. Fine by here.

The issue is that I need to export this data as DICOM series through vtkDICOMWriter. How much is possible that ?

6

You should put the data from vtkImageImport into vtkDICOMWriter.

Putting the data from vtkImageImport back into m_pImageExtractor makes no sense.

2 Likes
7

Sound logical and after I implemented this approach, work great ! Thank you !