[vtkusers] imagedata appearing upside down (sometimes..?)
Mathieu Malaterre
mathieu.malaterre at kitware.com
Mon Mar 22 21:44:00 EST 2004
Luke,
There a many ways to do it, maybe the easier is to use vtkImageFilp:
reader =vtk.vtkimagereader()
...
flipY = vtk.vtkImageFlip ()
flipY.SetInput (reader.GetOutput())
flipY.SetFilteredAxis (1)
HTH
Mathieu
Luke Hua wrote:
> Hi,
>
> Just read this thread. I happened to have same problem. I used
> vtkimagereader to read raw data and generated a surface, but found out
> it is in reverse direction.
>
> How could I reverse it?
>
> Thanks!
>
> Luke
>
> */Mathieu Malaterre <mathieu.malaterre at kitware.com>/* wrote:
>
> Howard,
>
> Ok that's what I wanted ! Where does your data comes from ? Did you
> know that VTK read the image data upside down ? Have a look at any
> image
> reader like png, jpeg, tiff. You'll see that we read starting from the
> bottom. So make sure your array is read starting from the bottom.
>
> Or more generally use an already existing reader.
>
> HTH,
> Mathieu
>
> Howard Katz wrote:
> > Also,
> > just note that I input data using:
> >
> >
> VelocityVsTimeSampleFloatArray->SetVoidArray(array,TotalTimePoints*TotalCycles*NumBins,
>
> > 1 );
> >
> > where array is a 1D float array whcih represents a 2D array through
> > subscirpt arithemtic by doing:
> >
> > array [ row*TotalColumns + col ] = value;
> >
> > Thanks..!
> > Howard
> >
> >> From: "Howard Katz"
> ! >> To: mathieu.malaterre at kitware.com
> >> CC: vtkusers at vtk.org
> >> Subject: Re: [vtkusers] imagedata appearing upside down
> (sometimes..?)
> >> Date: Mon, 22 Mar 2004 23:11:20 +0000
> >>
> >> Hi,
> >>
> >> I called GetSpacing and it returns (1,1,1) just as I had specified..
> >> And I know the input values are correct i.e they're not negative or
> >> anything because I also outputted this..
> >> And I noticed that whenever I don't add a camera to my renderer,
> >> nothing happens when I change the spacing, is this normal?
> >> Okay below is some C++ code,
> >> So again its werid because the whole thing appears upside down only
> >> for some cases and not others..?
> >> Anyways here it is:
> >>
> >> VelocityVsTimeSampleFloatArray->SetNumberOfComponents(1);
> >>
> VelocityVsTimeSampleFloatArray->SetNumberOfTuples(TotalCycles*NumVelocityBins*TotalTi!
> mePoints
> >> );
> >> VelocityVsTimeSampleImageData->SetOrigin(-30, -85, 0);
> >>
> VelocityVsTimeSampleImageData->GetPointData()->SetScalars(VelocityVsTimeSampleFloatArray);
>
> >>
> >>
> VelocityVsTimeSampleImageData->SetDimensions(TotalCycles*TotalTimePoints,NumVelocityBins,
>
> >> 1);
> >> VelocityVsTimeSampleImageData->SetScalarType(VTK_FLOAT);
> >> VelocityVsTimeSampleImageData->SetSpacing(1, 1, 1);
> >>
> >> ImageCast->SetInput( VelocityVsTimeSampleImageData);
> >> ImageCast->SetOutputScalarTypeToUnsignedChar();
> >>
> >> ImageMapToColors->SetInput(ImageCast->GetOutput());
> >> ImageMapToColors->SetLookupTable(SpectLUT);
> >>
> >> SpectActor->SetInput(ImageMapToColors->GetOutput());
> >> SpectActor->SetDisplayExtent( 0, TotalCycles*TotalTimePoints-1, 0,
> >> NumVelocityBins-1, 0, 0 );
> >>
> >> Cam->SetPosition(0, 0, 325);
> >> Cam->SetFocalPoint(0,0,0);
> >>
> >> Ren1->SetBackground(0.3, 0.3, 0.3);
> >> Ren1->SetActiveCamera(Cam);
> >> Ren1->AddActor( SpectActor );
> >>
> >> RenWin->AddRenderer( Ren1 );
> >> RenWin->SetSize( 500, 500 );
> >> RenWin->SetInteractor(Iren);
> >> Iren->SetStillUpdateRate(1000);
> >> Iren->SetDesiredUpdateRate(1000);
> >> Iren->Initialize();
> >> Iren->Render();
> >>
> >>
> >>
> >>
> >>> From: Mathieu Malaterre
> >>> To: Howard Katz
> >>> CC: vtkusers at vtk.org
> >>> Subject: Re: [vtkusers] imagedata appearing upside down
> (sometimes..?)
> >>> Date: Mon, 22 Mar 2004 17:34:30 -0500
> >>>
> >>> Howard,
> >>>
> >>> What does :
> >>>
> >>> //Call Update() before
> >>> print imagedata.GetSpacing()
> >>>
> >>> return ?
> >>> Could you reproduce the bad behavior using a tests from VTK ? Or
> >>> could you send us a python/c++/tcl code that shows this problem.
> >>>
> >>> Thanks
> >>> Mathieu
> >>>
> >>> Howard Katz wrote:
> >>>
> >>>> Hi..
> >>>> What do you mean my spacing 'can' be negative...?
> >>>> :S
> >>>> Thanks again..!
> >>>>
> >>>>
> >>>>
> >>>>> From: Mathieu Malaterre
> >>>>> To: Howard Katz
> >>>>> CC: vtkusers at vtk.org
> >>>>> Subject: Re: [vtkusers] imagedata appearing upside down
> (sometimes..?)
> >>>>> Date: Mon, 22 Mar 2004 13:! 13:18 -0500
> >>>>>
> >>>>> Howard Katz wrote:
> >>>>>
> >>>>>> Hi,
> >>>>>> so has anyone run into the problem where their vtkImageData
> looks
> >>>>>> upside down only sometiems depending on the input values..?
> i.e.
> >>>>>> I know I am inputting values 10, 20, 15 (for example) but these
> >>>>>> appear at rows -10, -20, -15 (..and this will happen for the
> >>>>>> entire image data)
> >>>>>>
> >>>>>> Can anyoen guess what my problem might be?
> >>>>>
> >>>>>
> >>>>>
> >>>>> You spacing can be negative, this happens typically in medical
> >>>>> image data such a MINC or DICOM
> >>>>>
> >>>>> HTH
> >>>>> Mathieu
> >>>>>
> >>>>>
> >>>>
> >>>> _________________________________________________________________
> >>>> All the action. All the drama. Get NCAA hoops coverage at MSN
> Sports
> >>>> by ESPN. http://msn.espn.go.com/index.html?partnersite=espn
> >>>>
> >>>>
> >>>
> >>>
> >>>
> >>> _______________________________________________
> >>> This is the private VTK discussion list. Please keep messages
> >>> on-topic. Check the FAQ at:
> >>> Follow this link to subscribe/unsubscribe:
> >>> http://www.vtk.org/mailman/listinfo/vtkusers
> >>
> >>
> >> _________________________________________________________________
> >> Get tax tips, tools and access to IRS forms ?all in one place at
> MSN
> >> Money! http://moneycentral.msn.com/tax/home.asp
> >>
> >> _______________________________________________
> >> This is the private VTK discussion list. Please keep messages
> >> on-topic. Check the FAQ at:
> >> Follow this link to subscribe/unsubscribe:
> >> http://www.vtk.org/mailman/listinfo/vtkusers
> >
> >
> > _________________________________________________________________
> > Is your PC infected? Get a FREE online computer virus scan from
> McAfee?
> > Security. http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
> >
> > _______________________________________________
> > This is the private VTK discussion list. Please keep messages
> on-topic.
> > Check the FAQ at:
> > Follow this link to subscribe/unsubscribe:
> > http://www.vtk.org/mailman/listinfo/vtkusers
> >
>
>
>
> _______________________________________________
> This is the private VTK discussion list.
> Please keep messages on-topic. Check the FAQ at:
> Follow this link to subscribe/unsubscribe:
> http://www.vtk.org/mailman/listinfo/vtkusers
>
> Do you Yahoo!?
> *Yahoo! Finance Tax Center* <http://taxes.yahoo.com/filing.html> - File
> online. File on time.
>
More information about the vtkusers
mailing list