Error in access different views - vtk

Question

I want to create Axial, Sagittal and Coronal views from a volume. At first I say that my volume is achieved from a series of DICOM images using DicomSeriesReadImageWrite2.cxx from itk library. The output is a .mha file.
Now I want to create different views using this data. So I used image ImageSlicing.cxx example. But the out put is a black window.
What shoud I do?
This is the code:
#include <vtkSmartPointer.h>
#include <vtkImageReader2.h>
#include <vtkImageData.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkInteractorStyleImage.h>
#include <vtkRenderer.h>
#include <vtkImageActor.h>
#include "vtkSmartPointer.h"
#include "vtkImageReader2.h"
#include "vtkMatrix4x4.h"
#include "vtkImageReslice.h"
#include "vtkLookupTable.h"
#include "vtkImageMapToColors.h"
#include "vtkImageActor.h"
#include "vtkRenderer.h"
#include "vtkRenderWindow.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkInteractorStyleImage.h"
#include "vtkCommand.h"
#include "vtkImageData.h"
#include "vtkImageMapper3D.h"
#include "vtkStreamingDemandDrivenPipeline.h"
#include "vtkInformation.h"
#include "vtkAutoInit.h"
VTK_MODULE_INIT(vtkRenderingOpenGL2); // VTK was built with vtkRenderingOpenGL2
VTK_MODULE_INIT(vtkInteractionStyle);
// The mouse motion callback, to turn "Slicing" on and off
class vtkImageInteractionCallback : public vtkCommand
{
public:
static vtkImageInteractionCallback *New() {
return new vtkImageInteractionCallback;
};
vtkImageInteractionCallback() {
this->Slicing = 0;
this->ImageReslice = nullptr;
this->Interactor = nullptr;
};
void SetImageReslice(vtkImageReslice *reslice) {
this->ImageReslice = reslice;
};
vtkImageReslice *GetImageReslice() {
return this->ImageReslice;
};
void SetInteractor(vtkRenderWindowInteractor *interactor) {
this->Interactor = interactor;
};
vtkRenderWindowInteractor *GetInteractor() {
return this->Interactor;
};
void Execute(vtkObject *, unsigned long event, void *) override
{
vtkRenderWindowInteractor *interactor = this->GetInteractor();
int lastPos[2];
interactor->GetLastEventPosition(lastPos);
int currPos[2];
interactor->GetEventPosition(currPos);
if (event == vtkCommand::LeftButtonPressEvent)
{
this->Slicing = 1;
}
else if (event == vtkCommand::LeftButtonReleaseEvent)
{
this->Slicing = 0;
}
else if (event == vtkCommand::MouseMoveEvent)
{
if (this->Slicing)
{
vtkImageReslice *reslice = this->ImageReslice;
// Increment slice position by deltaY of mouse
int deltaY = lastPos[1] - currPos[1];
reslice->Update();
double sliceSpacing = reslice->GetOutput()->GetSpacing()[2];
vtkMatrix4x4 *matrix = reslice->GetResliceAxes();
// move the center point that we are slicing through
double point[4];
double center[4];
point[0] = 0.0;
point[1] = 0.0;
point[2] = sliceSpacing * deltaY;
point[3] = 1.0;
matrix->MultiplyPoint(point, center);
matrix->SetElement(0, 3, center[0]);
matrix->SetElement(1, 3, center[1]);
matrix->SetElement(2, 3, center[2]);
interactor->Render();
}
else
{
vtkInteractorStyle *style = vtkInteractorStyle::SafeDownCast(
interactor->GetInteractorStyle());
if (style)
{
style->OnMouseMove();
}
}
}
};
private:
// Actions (slicing only, for now)
int Slicing;
// Pointer to vtkImageReslice
vtkImageReslice *ImageReslice;
// Pointer to the interactor
vtkRenderWindowInteractor *Interactor;
};
// The program entry point
int main(int argc, char *argv[])
{
//if (argc < 2)
//{
// cout << "Usage: " << argv[0] << " DATADIR/headsq/quarter" << endl;
// return 1;
//}
// Start by loading some data.
std::string inputFilename = "out.mha";
// Read file
vtkSmartPointer<vtkImageReader2> reader =
vtkSmartPointer<vtkImageReader2>::New();
reader->SetFileName(inputFilename.c_str());
reader->SetDataScalarTypeToUnsignedChar();
reader->Update();
// Calculate the center of the volume
int extent[6];
double spacing[3];
double origin[3];
reader->GetOutputInformation(0)->Get(vtkStreamingDemandDrivenPipeline::WHOLE_EXTENT(), extent);
reader->GetOutput()->GetSpacing(spacing);
reader->GetOutput()->GetOrigin(origin);
double center[3];
center[0] = origin[0] + spacing[0] * 0.5 * (extent[0] + extent[1]);
center[1] = origin[1] + spacing[1] * 0.5 * (extent[2] + extent[3]);
center[2] = origin[2] + spacing[2] * 0.5 * (extent[4] + extent[5]);
// Matrices for axial, coronal, sagittal, oblique view orientations
//static double axialElements[16] = {
// 1, 0, 0, 0,
// 0, 1, 0, 0,
// 0, 0, 1, 0,
// 0, 0, 0, 1 };
//static double coronalElements[16] = {
// 1, 0, 0, 0,
// 0, 0, 1, 0,
// 0,-1, 0, 0,
// 0, 0, 0, 1 };
static double sagittalElements[16] = {
0, 0,-1, 0,
1, 0, 0, 0,
0,-1, 0, 0,
0, 0, 0, 1 };
//static double obliqueElements[16] = {
// 1, 0, 0, 0,
// 0, 0.866025, -0.5, 0,
// 0, 0.5, 0.866025, 0,
// 0, 0, 0, 1 };
// Set the slice orientation
vtkSmartPointer<vtkMatrix4x4> resliceAxes =
vtkSmartPointer<vtkMatrix4x4>::New();
resliceAxes->DeepCopy(sagittalElements);
// Set the point through which to slice
resliceAxes->SetElement(0, 3, center[0]);
resliceAxes->SetElement(1, 3, center[1]);
resliceAxes->SetElement(2, 3, center[2]);
// Extract a slice in the desired orientation
vtkSmartPointer<vtkImageReslice> reslice =
vtkSmartPointer<vtkImageReslice>::New();
reslice->SetInputConnection(reader->GetOutputPort());
reslice->SetOutputDimensionality(2);
reslice->SetResliceAxes(resliceAxes);
reslice->SetInterpolationModeToLinear();
// Create a greyscale lookup table
vtkSmartPointer<vtkLookupTable> table =
vtkSmartPointer<vtkLookupTable>::New();
table->SetRange(0, 2000); // image intensity range
table->SetValueRange(0.0, 1.0); // from black to white
table->SetSaturationRange(0.0, 0.0); // no color saturation
table->SetRampToLinear();
table->Build();
// Map the image through the lookup table
vtkSmartPointer<vtkImageMapToColors> color =
vtkSmartPointer<vtkImageMapToColors>::New();
color->SetLookupTable(table);
color->SetInputConnection(reslice->GetOutputPort());
// Display the image
vtkSmartPointer<vtkImageActor> actor =
vtkSmartPointer<vtkImageActor>::New();
actor->GetMapper()->SetInputConnection(color->GetOutputPort());
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
renderer->AddActor(actor);
vtkSmartPointer<vtkRenderWindow> window =
vtkSmartPointer<vtkRenderWindow>::New();
window->AddRenderer(renderer);
// Set up the interaction
vtkSmartPointer<vtkInteractorStyleImage> imageStyle =
vtkSmartPointer<vtkInteractorStyleImage>::New();
vtkSmartPointer<vtkRenderWindowInteractor> interactor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
interactor->SetInteractorStyle(imageStyle);
window->SetInteractor(interactor);
window->Render();
vtkSmartPointer<vtkImageInteractionCallback> callback =
vtkSmartPointer<vtkImageInteractionCallback>::New();
callback->SetImageReslice(reslice);
callback->SetInteractor(interactor);
imageStyle->AddObserver(vtkCommand::MouseMoveEvent, callback);
imageStyle->AddObserver(vtkCommand::LeftButtonPressEvent, callback);
imageStyle->AddObserver(vtkCommand::LeftButtonReleaseEvent, callback);
// Start interaction
// The Start() method doesn't return until the window is closed by the user
interactor->Start();
return EXIT_SUCCESS;
}
and this is the output:

Answer 1

The problem was in reading data. I used pointer to read my data and problem solved.