Re: [vmtk-users] VMTK Point co-ordinates system

[Ahmed H. <ahm...@gm...>]

Dear Luca

I managed to solve my problem. I don't want to wast your time responding. I
converted the point co-ordinates from RAS to IJK. Also I wasn't passing the
point correctly.  Now it is working great.

Thanks

int VMTKseed1[3],VMTKseed2[3]; // fill it with points in IJK coordinates

    vtkIdList *my_VTKseedIdList1=vtkIdList::New();
    vtkIdList *my_VTKseedIdList2=vtkIdList::New();
    vtkIdType pttyp1,pttyp2;
     pttyp1=myVTKspeedImage->ComputePointId(VMTKseed1);
     pttyp2=myVTKspeedImage->ComputePointId(VMTKseed2);
    /**************/
    my_VTKseedIdList1->InsertNextId(pttyp1);
    my_VTKseedIdList2->InsertNextId(pttyp2);
    vtkvmtkCollidingFrontsImageFilter *myVMTKcollidingFronts =
vtkvmtkCollidingFrontsImageFilter::New();
    myVMTKcollidingFronts->SetInput(myVTKspeedImage);
    myVMTKcollidingFronts->SetSeeds1(my_VTKseedIdList1);
    myVMTKcollidingFronts->SetSeeds2(my_VTKseedIdList2);
    myVMTKcollidingFronts->ApplyConnectivityOn();
    myVMTKcollidingFronts->StopOnTargetsOn();
    myVMTKcollidingFronts->Update();

Ahmed A. Harouni


On Thu, Feb 21, 2013 at 12:30 PM, Ahmed Harouni <ahm...@gm...>wrote:

> Dear Luca
>
> Thanks for your previous help. I have managed to use
> vtkvmtkVesselnessMeasureImageFilter class and am displaying the
> results successfully to Osirix output. Now I trying to use
> vtkvmtkCollidingFrontsImageFilter. I am following the pythons scripts and
> getting the expected results.
> I can't determine ow to pass the two seed points to the
> vtkvmtkCollidingFrontsImageFilter class using the SetSeeds1. I think I am
> using the wrong co-ordinate system. I capture the ROI from Osirix which is
> given to me in RAS system in mm. My understanding that VMTK uses IJK system
> but it already has the origin and spacing values in the vtkImageData.
> Should I convert my point coordinate manually using matrix transformation
> or am I missing something? (Bellow is my code for
> vtkvmtkCollidingFrontsImageFilter)
>
> Thanks for your help.
>
>
>     vtkIdList *my_VTKseedIdList1=vtkIdList::New();
>     vtkIdList *my_VTKseedIdList2=vtkIdList::New();
> //    vtkSmartPointer<vtkPoints> point11
> =vtkSmartPointer<vtkPoints>::New();
>     vtkPoints *point11 =vtkPoints::New();
>     vtkPoints *points22=vtkPoints::New();
>     vtkIdType pttyp1,pttyp2;
>
>
> pttyp1=point11->InsertNextPoint(5,5,5);//(15.3,110.8,946.2);//{0,90,922};//{283,242,251};//
> {18.5,-148.0,115};
>     pttyp2=points22->InsertNextPoint(15,15,15);//(-10.8,95.8,931);//
> {80,146,951};//{ 338,276, 218};//{44.0, -155.0, 110.5};
>     my_VTKseedIdList1->InsertNextId(pttyp1);
>     my_VTKseedIdList2->InsertNextId(pttyp2);
>
>     vtkvmtkCollidingFrontsImageFilter *myVMTKcollidingFronts =
> vtkvmtkCollidingFrontsImageFilter::New();
>     myVMTKcollidingFronts->SetInput(myVTKspeedImage);
> //myVTKspeedImage is:   vtkImageData * myVTKspeedImage and I call it's
> update function and I see the expected results when displaying it.
>     myVMTKcollidingFronts->SetSeeds1(my_VTKseedIdList1);
>     myVMTKcollidingFronts->SetSeeds2(my_VTKseedIdList2);
>     myVMTKcollidingFronts->ApplyConnectivityOn();
>     myVMTKcollidingFronts->StopOnTargetsOn();
>     myVMTKcollidingFronts->Update();  // I get an empty image !
>
>
> Ahmed A. Harouni
>