Access Reading Violation when writing a DICOM with vtkDICOMWriter

I'm trying to write vtkImageData as a DICOM. I keep getting an "Access Reading Violation" when I try to write the image.

Unhandled exception at 0x00007FFDA30ECA50 : 0xC0000005: Access violation reading location 0x000001BD38D5C000

Here is my code:

vtkSmartPointer<vtkDICOMWriter> dcmWriter = vtkSmartPointer<vtkDICOMWriter>::New();
dcmWriter->SetInputData(testDat);
dcmWriter->SetFileName(fullPath.toStdString().c_str());
dcmWriter->Update(); // this line breaks
dcmWriter->Write(); 

testDat is a vtkSmartPointer<vtkImageData> type and has data in it. Any thoughts on whats causing the error? I can't find anything similar online.

I followed this example: https://github.com/dgobbi/vtk-dicom/blob/master/Examples/TestDICOMWriter.cxx

I don't have metadata, but that shouldn't be a problem.

I need to make some guesses here because you didn't post all of your code, but I suspect that the problem happens in the following line:

dcmWriter->SetFileName(fullPath.toStdString().c_str());

toStdString() is most probably returning a temporary std::string (fullPath looks like a Qt QString), on which you call c_str(). After the statement, your temporary is destroyed and whatever you have passed to SetFileName is now a dangling pointer. Hence the segfault.

Try the following instead::

const auto pathString = fullPath.toStdString();
dcmWriter->SetFileName(pathString.c_str());

This should hopefully work fine. Even if not, it definitely is an issue with your code.