[Insight-users] Two bugs with IntensityBased2D3DRegistration.cxx--one fixed, one open

[Jian Wu]

Dear itk users:

1) I fixed one bug. To get IntensityBased2D3DRegistration.cxx to run, the 
following correction needs to be made.

=============================================================
File Name: IntensityBased2D3DRegistration.cxx
Line Number: 994
Original:
  itk::Optimizer::ScalesType weightings( 6 );
Replaced by:
  itk::Optimizer::ScalesType weightings( transform->GetNumberOfParameters() 
);
=============================================================

2) There was a problem with the 
metric--GradientDifferenceImageToImageMetric. The member function 
GetDerivative() always returned zero. (See lines 461-484 in 
itkGradientDifferenceImageToImageMetric.txx). It appears the variables 
valuep1 and valuep0 always have identical values no matter how the 
transformation parameters were changed. I guess the outputs from the 
TransformMovingImageFilter and the MovedSobelFilters had not been properly 
updated. I could not figure out how to correct it. This problem caused the 
registration stopped at the first iteration and went nowhere.

ITK Toolkit version: 2.4.1
Compiler: Microsoft VC++ 6.0
OS: Window XP Professional

Please help!

Jian Wu