[vtkusers] Closed vtkPolyLine to binary image

Mon Jul 12 10:28:37 EDT 2010

Dirk,

try to place the stripper between polyreader->GetOutput() and circle, i.e.
vtkSmartPointer<vtkPolyData> circle = stripper->GetOutput();
Let me know whether it helped.

lars

-------- Original-Nachricht --------
> Datum: Mon, 12 Jul 2010 16:16:49 +0200
> Von: "Dirk Boye" <body at nabla.org>
> An: "Lars Friedrich Lars" <lars-friedrich at gmx.net>
> CC: "Dirk Boye" <body at nabla.org>, vtkusers at vtk.org
> Betreff: Re: [vtkusers] Closed vtkPolyLine to binary image

> I ran your example and the only difference between stripper->GetOutput()
> and my outline were the normals.
> 
> My code is as follows: (your code but with a readin of my circle
> and given image dimensions etc.)
> 
> The vtk File can be found here:
> http://www.nabla.org/circle.vtk
> 
> The resulting image is black only.
> 
> 
> #include <vtkSmartPointer.h>
> #include <vtkPolyData.h>
> #include <vtkImageData.h>
> #include <vtkSphereSource.h>
> #include <vtkMetaImageWriter.h>
> #include <vtkPolyDataToImageStencil.h>
> #include <vtkImageStencil.h>
> #include <vtkPointData.h>
> #include <vtkCutter.h>
> #include <vtkPlane.h>
> #include <vtkStripper.h>
> #include <vtkLinearExtrusionFilter.h>
> #include <vtkXMLPolyDataWriter.h>
> #include <vtkPolyDataReader.h>
> 
> int main(int argc, char **argv)
> {
> vtkSmartPointer< vtkPolyDataReader > polyreader=vtkSmartPointer<
> vtkPolyDataReader >::New();
> 	polyreader->SetFileName("circle.vtk");
> 	polyreader->Update();
> 
> 	vtkSmartPointer<vtkPolyData> circle = polyreader->GetOutput();
> 
> 	// prepare the binary image's voxel grid
> 	vtkSmartPointer<vtkImageData> whiteImage =
> 	  vtkSmartPointer<vtkImageData>::New();
> 	double spacing[3]; // desired volume spacing
> 	spacing[0] = 2.0;
> 	spacing[1] = 2.0;
> 	spacing[2] = 2.0;
> 	whiteImage->SetSpacing(spacing);
> 
> 	// compute dimensions
> 	int dim[3]={256,256,1};
> 	whiteImage->SetDimensions(dim);
> 	whiteImage->SetExtent(0, dim[0] - 1, 0, dim[1] - 1, 0, dim[2] - 1);
> 	double origin[3]={0,0,0};
> 	whiteImage->SetOrigin(origin);
> 	whiteImage->SetScalarTypeToUnsignedChar();
> 	whiteImage->AllocateScalars();
> 	// fill the image with foreground voxels:
> 	unsigned char inval = 255;
> 	unsigned char outval = 0;
> 	vtkIdType count = whiteImage->GetNumberOfPoints();
> 	for (vtkIdType i = 0; i < count; ++i)
> 	{
> 		whiteImage->GetPointData()->GetScalars()->SetTuple1(i, inval);
> 	}
> 
> 	// sweep polygonal data (this is the important thing with contours!)
> 	vtkSmartPointer<vtkLinearExtrusionFilter> extruder =
> 	  vtkSmartPointer<vtkLinearExtrusionFilter>::New();
> 	extruder->SetInput(circle);
> 	extruder->SetScaleFactor(1.);
> 	extruder->SetExtrusionTypeToNormalExtrusion();
> 	extruder->SetVector(0, 0, 1);
> 	extruder->Update();
> 
> 	// polygonal data --> image stencil:
> 	vtkSmartPointer<vtkPolyDataToImageStencil> pol2stenc =
> 	vtkSmartPointer<vtkPolyDataToImageStencil>::New();
> 	pol2stenc->SetTolerance(0); // important if extruder->SetVector(0, 0, 1)
> !!!
> 	pol2stenc->SetInputConnection(extruder->GetOutputPort());
> 	pol2stenc->SetOutputOrigin(origin);
> 	pol2stenc->SetOutputSpacing(spacing);
> 	pol2stenc->SetOutputWholeExtent(whiteImage->GetExtent());
> 	pol2stenc->Update();
> 
> 	// cut the corresponding white image and set the background:
> 	vtkSmartPointer<vtkImageStencil> imgstenc =
> 	vtkSmartPointer<vtkImageStencil>::New();
> 	imgstenc->SetInput(whiteImage);
> 	imgstenc->SetStencil(pol2stenc->GetOutput());
> 	imgstenc->ReverseStencilOff();
> 	imgstenc->SetBackgroundValue(outval);
> 	imgstenc->Update();
> 
> 	vtkSmartPointer<vtkMetaImageWriter> imageWriter =
> 	vtkSmartPointer<vtkMetaImageWriter>::New();
> 	imageWriter->SetFileName("labelImage.mhd");
> 	imageWriter->SetInput(imgstenc->GetOutput());
> 	imageWriter->Write();
> 
> 	return 0;
> };
> 
> 
> >
> > vtkPolyDataNormals
> >
> > just to satisfy my curiosity:
> > why are you of the opinion that missing normals are a problem for that
> > approach? I copied the piece of example code more or less from an old
> > application I programmed some months ago; as far as I can remember, my
> > input polygons did not have any normals defined, and it worked though
> ...
> >
> > regards,
> > lars
> >
> > -------- Original-Nachricht --------
> >> Datum: Mon, 12 Jul 2010 15:30:01 +0200
> >> Von: "Dirk Boye" <body at nabla.org>
> >> An: "Lars Friedrich Lars" <lars-friedrich at gmx.net>
> >> CC: "Dirk Boye" <body at nabla.org>, vtkusers at vtk.org
> >> Betreff: Re: [vtkusers] Closed vtkPolyLine to binary image
> >
> >> Hi Lars,
> >>
> >> Thank you for your help. My problem now seems to be, that my contour
> >> lines
> >> don't have any normals.
> >>
> >> Do you know if there's some function to generate the normals?
> >>
> >> Cheers,
> >> Dirk
> >>
> >> > Hi,
> >> >
> >> > I added a small example:
> >> >
> >> >
> >>
> http://www.cmake.org/Wiki/VTK/Examples/PolyData/PolyDataContourToImageData
> >> >
> >> > Hope that helps you.
> >> >
> >> > However, please read the NOTE in the description. Maybe you could fix
> >> /
> >> > verify the image origin problem.
> >> >
> >> > regards,
> >> > lars
> >> >
> >> > -------- Original-Nachricht --------
> >> >> Datum: Mon, 12 Jul 2010 08:36:32 +0200
> >> >> Von: "Dirk Boye" <body at nabla.org>
> >> >> An: vtkusers at vtk.org
> >> >> Betreff: [vtkusers] Closed vtkPolyLine to binary image
> >> >
> >> >> Dear list,
> >> >>
> >> >> let's say I have a closed vtkPolyLine in 2D and points are
> >> >> ordered clockwise and last point=first point.
> >> >> The resulting Polygon is non-convex.
> >> >>
> >> >> I'd like to create a binary image
> >> >> from that. Ones inside the line, zeros outside. See picture:
> >> >> http://www.nabla.org/circlecontour.png
> >> >>
> >> >> Is there an filter to do that? Or do I have to check all pixels,
> >> >> if they are inside?
> >> >>
> >> >>
> >> >> Cheers,
> >> >> Dirk
> >> >>
> >> >>
> >> >>
> >> >> _______________________________________________
> >> >> 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
> >> >
> >> > --
> >> > GMX DSL: Internet-, Telefon- und Handy-Flat ab 19,99 EUR/mtl.
> >> > Bis zu 150 EUR Startguthaben inklusive!
> >> http://portal.gmx.net/de/go/dsl
> >> >
> >> >
> >
> > --
> > GRATIS fÃ¼r alle GMX-Mitglieder: Die maxdome Movie-FLAT!
> > Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01
> >
> >

-- 
GMX DSL: Internet-, Telefon- und Handy-Flat ab 19,99 EUR/mtl.  
Bis zu 150 EUR Startguthaben inklusive! http://portal.gmx.net/de/go/dsl