[Insight-users] Canny filter problems

[Joshua Cates]

Hi,

Try casting your image to float before the edge detector (and back to int
or char or whatever type you need after).  This is a common problem with
some of the basic image processing filters: they expect real number input
and don't automatically convert from non floating point types.  It will be
fixed in the future, but for now you will need to explicitly cast.

Hope this helps.

Josh.

______________________________
 Josh Cates
 School of Computer Science
 University of Utah
 Email: cates@sci.utah.edu
 Phone: (801) 587-7697
 URL:   www.cs.utk.edu/~cates


On Tue, 30 Jul 2002, Renaud Winzenrieth wrote:

> Hi everybody,
> I have some problems with the canny filter.
> I do this:
> vtkBMPreader->vtkImageLuminance->vtkImageCast->vtkImageExport
> ->itkImageImportType->itkCannyEdgeDetectionImageFilter->itkVTKImageExport
> ->itkImageExportType->vtkImageImport->vtkImageCast->vtkImageMapper
> ->vtkActor2D->vtkRenderer->......->Render()
> My problem is that i obtaine a black window. If I skip the canny filter
> step everything is ok.
> anybody can help me?
>
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