[Insight-users] registering images from thumbnails

[Mauro Maiorca]

Hi all,

 I'm registering 2 CT volumes (rigid transformation). In order to
speed up the process I'm subsampling the original images prior to
registration. I'm using ImageRegistration8.cxx on the two thumbnails
(fixed and moving image) and it's working fine: the two thumbnails are
pretty much aligned. Now, how to apply the transformation to the
original moving volume?

I guess, prior to "transform->SetParameters( finalParameters );" I
have to retrieve the registration parameters:

 OptimizerType::ParametersType finalParameters =
registration->GetLastTransformParameters();

and modify parameters according to the subsampling ratio, but I'm not
sure about how the parameters are actually stored in
OptimizerType::ParametersType, there are mm? rotation is in radiants?
In which order are stored? There is any ITK function to automatically
calculate the actual parameters, or should I calculate them manually?

thanks,
Mauro