[vtkusers] Rotate vtkImage with vtkmatrix4x4

[David Gobbi]

Hi Jothy,

It can't be set directly, but it is the Position -> FocalPoint vector, so you
can set it by setting the camera position and focal point.

 - David

On Wed, Mar 2, 2011 at 5:24 AM, Jothy <jothybasu at gmail.com> wrote:
> How to set the DirectionOfProjection, its a pted member. And theres is no
> SetDirectionOfProjection in vtkCamera.
>
> Thanks
>
> Jothy
>
> On Tue, Mar 1, 2011 at 5:45 PM, David Gobbi <david.gobbi at gmail.com> wrote:
>>
>> Hi Jothy,
>>
>> If you work with sagittal and coronal image you will have to worry about
>> image orientation, but with axial images everything is identity.
>>
>> For axial images, just make sure that your camera ViewUp is (0, -1, 0)
>> and DirectionOfProjection is (0, 0, 1).  The direction of projection for
>> the camera is the (FocalPoint - Position) direction.
>>
>>  - David
>>
>>
>> On Tue, Mar 1, 2011 at 10:36 AM, Jothy <jothybasu at gmail.com> wrote:
>> > Hi David,
>> >
>> > I have given up using vtkImageViewer2 right from the beginign of this
>> > project!
>> >
>> > Since it has problem with actors with varying z position - if your
>> > actors
>> > are from cutter ( some go behind the viewer).I am using vtkImageActor
>> > with
>> > vtkImageMapToColors and vtkImageReslice.
>> >
>> > The match between the dose and CT is perfect, except the view is upside
>> > down.
>> >
>> > So you mean there is no point in setting rotation and instead use the
>> > camera
>> > orientation.
>> >
>> > Thanks
>> >
>> > Jothy
>> >
>> > On Tue, Mar 1, 2011 at 5:26 PM, David Gobbi <david.gobbi at gmail.com>
>> > wrote:
>> >>
>> >> Hi Jothy,
>> >>
>> >> If your ImageOrientationPatient is 1 0 0 0 1 0 then the direction
>> >> cosines will be the identity matrix.
>> >>
>> >> So the image is fine, my guess is that vtkImageViewer2 is the
>> >> problem.  As I've said in other emails, I never use vtkImageViewer2.
>> >> But digging into its code, I see this:
>> >>
>> >>      case vtkImageViewer2::SLICE_ORIENTATION_XY:
>> >>        cam->SetFocalPoint(0,0,0);
>> >>        cam->SetPosition(0,0,1); // -1 if medical ?
>> >>        cam->SetViewUp(0,1,0);
>> >>        break;
>> >>
>> >> This view orientation is NOT the proper axial orientation for
>> >> DICOM patient coordinates.  In DICOM, Y increases in the
>> >> A-P direction (top-down), but vtkImageViewer2 has Y increase
>> >> from bottom to top.
>> >>
>> >> I suggest that you give up on vtkImageViewer2.  As I've said
>> >> before, I always use vtkImageActor to display images, and I
>> >> set the camera orientation myself.  And I use FileLowerLeftOn.
>> >>
>> >> And it is moot now, but the math here is incorrect:
>> >>  reslice->SetElement(0,3,IPP[0]);
>> >>  reslice->SetElement(1,3,IPP[1]);
>> >>  reslice->SetElement(2,3,IPP[2]);
>> >>
>> >> This applies a translation by IPP after the rotation, which is
>> >> not the same thing as rotating about IPP.
>> >>
>> >>  - David
>> >>
>> >>
>> >>
>> >> On Tue, Mar 1, 2011 at 9:58 AM, Jothy <jothybasu at gmail.com> wrote:
>> >> > Yes it doesn't rotate at all!
>> >> >
>> >> > My axial elements were
>> >> >
>> >> > reslice->DeepCopy( imageReader->GetDirectionCosines());
>> >> > reslice->SetElement(0,3,IPP[0]);
>> >> > reslice->SetElement(1,3,IPP[1]);
>> >> > reslice->SetElement(2,3,IPP[2]);
>> >> >
>> >> > My images have
>> >> >
>> >> > Image position: -275 -524 -122.441
>> >> > Image Dims: 512 512 98
>> >> > Image Origin: -275 -524 -122.441
>> >> > ImageOrient: 1 0 -1.22465e-16 0 1 0
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> > But this is changing only the y axis (some translation in Y). But no
>> >> > rotation.
>> >> >
>> >> > Any help is greatly appreciated.
>> >> >
>> >> > Thanks again
>> >> >
>> >> > Jothy
>> >> >
>> >> > On Tue, Mar 1, 2011 at 4:42 PM, David Gobbi <david.gobbi at gmail.com>
>> >> > wrote:
>> >> >>
>> >> >> Hi Jothy,
>> >> >>
>> >> >> When you say "doesn't rotate the image", do you mean that it does
>> >> >> nothing at all?  What are the elements of your direction cosines
>> >> >> matrix?
>> >> >>
>> >> >> Also, note that direction cosines matrix is a pure rotation matrix.
>> >> >> i.e. it rotates about (0,0,0).  You need to create a matrix that
>> >> >> rotates around a particular point in space.
>> >> >>
>> >> >>  - David
>> >> >>
>> >> >>
>> >> >> On Tue, Mar 1, 2011 at 9:28 AM, Jothy <jothybasu at gmail.com> wrote:
>> >> >> > Thanks!
>> >> >> >
>> >> >> > Now my images appeasr like the one shown in figure.
>> >> >> >
>> >> >> > I need to rotate the image and dose about the ImagePositionPatient
>> >> >> > upside-down.
>> >> >> >
>> >> >> > I tried vtkImageFlip - it invalidates the dicom coordinate system
>> >> >> > and
>> >> >> > the
>> >> >> > dose and image doesn't match.
>> >> >> >
>> >> >> > I tried this
>> >> >> >
>> >> >> >       vtkMatrix4x4 *invert = vtkMatrix4x4::New();
>> >> >> >
>> >> >> >         invert->DeepCopy( imageReader->GetDirectionCosines());
>> >> >> >
>> >> >> >         invert->Invert();
>> >> >> >
>> >> >> >         vtkImageReslice *reslice = vtkImageReslice::New();
>> >> >> >
>> >> >> >         reslice->SetResliceAxes( invert );
>> >> >> >
>> >> >> >         reslice->SetInput(this->imageData);
>> >> >> >
>> >> >> >         reslice->Update();
>> >> >> >
>> >> >> >
>> >> >> > But it doesn't rotate the image.How to rotate the image?
>> >> >> >
>> >> >> > Thanks
>> >> >> >
>> >> >> > Jothy
>> >> >> >
>> >> >> >
>> >> >> > On Tue, Mar 1, 2011 at 4:07 PM, Jothy <jothybasu at gmail.com> wrote:
>> >> >> >>
>> >> >> >> But in this example FileLowerLeft is switched off.
>> >> >> >>
>> >> >> >> Thanks
>> >> >> >>
>> >> >> >> Jothy
>> >> >> >>
>> >> >> >> On Tue, Mar 1, 2011 at 3:50 PM, Mathieu Malaterre
>> >> >> >> <mathieu.malaterre at gmail.com> wrote:
>> >> >> >>>
>> >> >> >>> jothy, I think what you are looking for is already in gdcm, have
>> >> >> >>> a
>> >> >> >>> look
>> >> >> >>> at:
>> >> >> >>> gdcmreslice.cxx
>> >> >> >>>
>> >> >> >>> hth
>> >> >> >>> On Tue, Mar 1, 2011 at 4:31 PM, Jothy <jothybasu at gmail.com>
>> >> >> >>> wrote:
>> >> >> >>> > Hi all,
>> >> >> >>> >
>> >> >> >>> > I am trying to rotate vtkImageData using vtkMatrix4x4 about a
>> >> >> >>> > point.
>> >> >> >>> > is
>> >> >> >>> > there any example on how to do this?
>> >> >> >>> >
>> >> >> >>> > Thanks
>> >> >> >>> >
>> >> >> >>> > Jothy
>> >> >> >>> >
>> >> >> >>> > _______________________________________________
>> >> >> >>> > Powered by www.kitware.com
>> >> >> >>> >
>> >> >> >>> > Visit other Kitware open-source projects at
>> >> >> >>> > http://www.kitware.com/opensource/opensource.html
>> >> >> >>> >
>> >> >> >>> > Please keep messages on-topic and check the VTK FAQ at:
>> >> >> >>> > http://www.vtk.org/Wiki/VTK_FAQ
>> >> >> >>> >
>> >> >> >>> > Follow this link to subscribe/unsubscribe:
>> >> >> >>> > http://www.vtk.org/mailman/listinfo/vtkusers
>> >> >> >>> >
>> >> >> >>> >
>> >> >> >>>
>> >> >> >>>
>> >> >> >>>
>> >> >> >>> --
>> >> >> >>> Mathieu
>> >> >> >>
>> >> >> >
>> >> >> >
>> >> >> > _______________________________________________
>> >> >> > Powered by www.kitware.com
>> >> >> >
>> >> >> > Visit other Kitware open-source projects at
>> >> >> > http://www.kitware.com/opensource/opensource.html
>> >> >> >
>> >> >> > Please keep messages on-topic and check the VTK FAQ at:
>> >> >> > http://www.vtk.org/Wiki/VTK_FAQ
>> >> >> >
>> >> >> > Follow this link to subscribe/unsubscribe:
>> >> >> > http://www.vtk.org/mailman/listinfo/vtkusers
>> >> >> >
>> >> >> >
>> >> >
>> >> >
>> >
>> >
>
>