[ITK-users] Setting tolerance is ignored

[Chr. Rossmanith]

Hi,

I have two images with slightly differing image origins:

InputImage Origin: [-7.9896713e+01, -7.0397179e+01, 0.0000000e+00]
InputImage_1 Origin: [-7.9896706e+01, -7.0397186e+01, 0.0000000e+00]

which are used as input for MaskImageFilter. Processing fails with the 
error "Inputs do not occupy the same physical space!" and tolerance 
being reported as 4.6875000e-07 even if I set it to 0.001 by 
filter->SetGlobalDefaultCoordinateTolerance( 0.001 ).

If itkImageToImageFilter would call 
GetGlobalDefaultCoordinateTolerance() instead of using 
this->m_CoordinateTolerance in VerifyInputInformation() the user defined 
tolerance is used.

Is this a bug or is the current behaviour intended?

Regards,
Christina Rossmanith
--
Dept. of Neurology
University Medicine Mannheim
University of Heidelberg


--------------------------------------------- Code 
----------------------------------------------------------------------------

#include "itkImageFileReader.h"
#include "itkMaskImageFilter.h"

int main (int argc, char *argv[])
{
   const unsigned int Dimension = 3;
   typedef short PixelType;
   typedef itk::Image< PixelType, Dimension > ImageType;

   typedef itk::ImageFileReader< ImageType > ReaderType;
   ReaderType::Pointer reader = ReaderType::New();
   reader->SetFileName( argv[1] );
   reader->Update();
   ReaderType::Pointer mask = ReaderType::New();
   mask->SetFileName( argv[2] );
   mask->Update();

   typedef itk::MaskImageFilter< ImageType, ImageType > FilterType;
   FilterType::Pointer filter = FilterType::New();
   filter->SetGlobalDefaultCoordinateTolerance( 0.001 );
   filter->SetInput1( reader->GetOutput() );
   filter->SetInput2( mask->GetOutput() );

   try
     {
       filter->Update();
     }
   catch ( itk::ExceptionObject & e )
     {
       std::cout << "MaskImageFilter failed: " << e << std::endl;
       return EXIT_FAILURE;
     }

   return EXIT_SUCCESS;
}