[vtkusers] problem in estimating the curvature

[Arnaud Gelas]

Right, you can!
mean curvature: 
http://www.itk.org/Doxygen/html/classitk_1_1QuadEdgeMeshDiscreteMeanCurvatureEstimator.html
max curvature: 
http://www.itk.org/Doxygen/html/classitk_1_1QuadEdgeMeshDiscreteMaxCurvatureEstimator.html
min curvature: 
http://www.itk.org/Doxygen/html/classitk_1_1QuadEdgeMeshDiscreteMinCurvatureEstimator.html

You can also refer to this paper for more information:
http://www.insight-journal.org/browse/publication/302
(The code is now part of itk)

Keep in mind that you should first extract one surface, before 
estimating curvatures.

Arnaud

Martine Lefevre wrote:
> Thanks Arnaud
> Can we get also the curvature mean, min and max with Itk? 
> Martine
>
> --- En date de : *Lun 26.1.09, Arnaud Gelas 
> /<arnaud_gelas at hms.harvard.edu>/* a écrit :
>
>     De: Arnaud Gelas <arnaud_gelas at hms.harvard.edu>
>     Objet: Re: [vtkusers] problem in estimating the curvature
>     À: "martine_lef at yahoo.fr" <martine_lef at yahoo.fr>
>     Cc: "vtk" <vtkusers at vtk.org>
>     Date: Lundi 26 Janvier 2009, 15h27
>
>     Hi Martine,
>
>     vtkCurvatures processes vtkPolyData. Thus, if you want to compute Gaussian
>     curvature, you have to extract one surface from your image (e.g. by using a
>     Marching Cubes).
>
>     Note that you can now directly compute the Gaussian curvature of a given
>     surface in itk by using itk::QuadEdgeMeshDiscreteGaussianCurvatureEstimator.. The
>     way to estimate the Gaussian curvature is less sensitive to the connectivity
>     than the vtk version.
>
>     http://www.itk.org/Doxygen/html/classitk_1_1QuadEdgeMeshDiscreteGaussianCurvatureEstimator.html
>
>     Arnaud
>
>     Martine Lefevre wrote:
>     > Hi
>     > I try to estimate the curvature information of an object but I failed. In
>     run time I get vtkOutpouWindow saying there is an error in the file
>     vtkDemandDrivenPipeline.cxx.
>     > My input volume is an itk image that I convert to vtk image in order to
>     estimate the curvature.
>     > I paste my code here. Any help is appreciated.
>     > Thank you.
>     >  Regards
>     > Martine
>     > 
>     >  
>     >  
>     > #include "itkImage.h"
>     > #include "itkImageFileReader.h"
>     > #include "itkImageFileWriter.h"
>     > #include "itkVTKImageExport.h"
>     > #include "itkVTKImageImport.h"
>     > #include "vtkImageData.h"
>     > #include "vtkImageImport.h"
>     > #include "vtkImageExport.h"
>     > #include "vtkCurvatures.h"
>     >  // This function will connect the given itk::VTKImageExport filter to the
>     given vtkImageImport filter.
>     > template <typename ITK_Exporter, typename VTK_Importer>
>     > void ConnectPipelines(ITK_Exporter exporter, VTK_Importer* importer)
>     > {
>     >
>     importer->SetUpdateInformationCallback(exporter->GetUpdateInformationCallback());
>     >
>     importer->SetPipelineModifiedCallback(exporter->GetPipelineModifiedCallback());
>     >
>     importer->SetWholeExtentCallback(exporter->GetWholeExtentCallback());
>     > importer->SetSpacingCallback(exporter->GetSpacingCallback());
>     > importer->SetOriginCallback(exporter->GetOriginCallback());
>     > importer->SetScalarTypeCallback(exporter->GetScalarTypeCallback());
>     >
>     importer->SetNumberOfComponentsCallback(exporter->GetNumberOfComponentsCallback());
>     >
>     importer->SetPropagateUpdateExtentCallback(exporter->GetPropagateUpdateExtentCallback());
>     > importer->SetUpdateDataCallback(exporter->GetUpdateDataCallback());
>     > importer->SetDataExtentCallback(exporter->GetDataExtentCallback());
>     >
>     importer->SetBufferPointerCallback(exporter->GetBufferPointerCallback());
>     > importer->SetCallbackUserData(exporter->GetCallbackUserData());
>     > }
>     > int main()
>     > {
>     > typedef float PixelType;
>     > const unsigned int Dimension = 3;
>     > typedef itk::Image< PixelType, Dimension > ImageType;
>     > typedef itk::ImageFileReader< ImageType > ReaderType;
>     > typedef itk::ImageFileWriter <ImageType> WriterType;
>     > ReaderType::Pointer reader = ReaderType::New();
>     > WriterType::Pointer writer = WriterType::New();
>     > reader->SetFileName("C:/work/MyImages/MyObject.hdr");
>     > // convert itk to vtk image type
>     > typedef itk::VTKImageExport< ImageType > ExportFilterType;
>     > ExportFilterType::Pointer itkExporter = ExportFilterType::New();
>     > itkExporter->SetInput( reader->GetOutput() );
>     > // Create the vtkImageImport and connect it to the itk::VTKImageExport
>     instance.
>     > vtkImageImport* vtkImporter = vtkImageImport::New();
>     > ConnectPipelines(itkExporter, vtkImporter);
>     > // estimate the curvature mean
>     > vtkCurvatures* myCurvatures= vtkCurvatures::New();
>     > myCurvatures->SetCurvatureTypeToGaussian();
>     > myCurvatures->SetInput(vtkImporter->GetOutput());
>     > myCurvatures->Update();
>     > std::cout << "end of the code !" << std::endl;
>     > std::cin.get();
>     > return 0;
>     > }
>     > 
>     > 
>
>               
>
>