I would like to have a better understanding about dicom volume rendering.
I have a set of dicom images, from which I've been able to extract axial, coronal and sagittal cuts, as follow :
I first wanted to generate a 3D model from scratch, but it seems to be way too hard.
So I heard about VTK/ITK, and I've been using this code to generate a .vtk file from my set of images :
http://www.itk.org/Doxygen46/html/IO_2DicomSeriesReadImageWrite2_8cxx-example.html
It works, but I need some explanations :
When I open this file with ParaView, I get the following result :
First, it might be a stupid question, but why is it blue?
Is there a way to cut and see the inside of the model?
My aim is not to use ParaView, and I'd like to make my own .vtk reader, I found this code I don't remember where, which I think is suppose to work, but all I get with it is the green background with nothing more :
#include <vtkPolyDataReader.h>
#include <vtkSmartPointer.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
int main ( int argc, char *argv[] ) {
// Parse command line arguments
if (argc != 2) {
std::cerr << "Usage: " << argv[0] << " Filename(.vtk)" << std::endl;
return EXIT_FAILURE;
}
std::string filename = argv[1];
// Read all the data from the file
vtkSmartPointer<vtkPolyDataReader> reader = vtkSmartPointer<vtkPolyDataReader>::New();
reader->SetFileName(filename.c_str());
reader->Update();
// Visualize
vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
mapper->SetInputConnection(reader->GetOutputPort());
vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
renderer->AddActor(actor);
renderer->SetBackground(.3, .6, .3); // Background color green
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
any idea why? I saw in ParaView that I had to activate the "Volume" mode to be able to see my model, is there something similar to handle here?
Last thing, which is very important : Is it possible to modify the 3D volume inside a .vtk file? For instance, if I want to change the color of a specific part of the model, does VTK provides tools allowing that?
