[Insight-users] Seg fault while using itkMutualInformationImageToImageMetric

[Tuhin]

Hello all,

  I am trying to use the itkMutualInformationImageToImageMetric class to 
calculate the mutual information between two images.  I don't want to 
register the images using itk, I just want the mutual information.  I have 
tried to get the following code to run on a Linux box with last night's itk 
source and I get a seg-fault (no exception is raised) at the last line in the 
try block.  Any regarding my issue would be appreciated.

TIA,

Tuhin

  //My typedefs
  typedef itk::Image<unsigned char,3> ImageType;
  typedef itk::MutualInformationImageToImageMetric<ImageType,ImageType>
	MetricType;
  typedef itk::QuaternionRigidTransform<double> TransformType;
  typedef itk::ImageRegistrationMethod<ImageType,ImageType> RegistrationType;

  //Set up the ITK MutualInformation calculator
  MetricType::Pointer mi = MetricType::New();
  MetricType::ParametersType params;
  TransformType::Pointer transform = TransformType::New();
  RegistrationType::Pointer reg = RegistrationType::New();

  try {
    mi->SetMovingImageStandardDeviation(1);
    mi->SetFixedImageStandardDeviation(1);
    mi->SetNumberOfSpatialSamples(50);
    
    reg->SetMetric(mi);
    reg->SetTransform(transform);
    reg->SetFixedImage(orig_imp->GetOutput());
    reg->SetMovingImage(defo_imp->GetOutput());

    params.resize(7);
    for(int i = 0; i < 7; i++) {
      params(i) = 0;      
    }
    params(3) = 1;
    cout << mi->GetValue(params) << endl;
  }
  catch (itk::ExceptionObject &e) {
    cout << "Exception detected: " << e;
    return -1;
  }