typedef clitk::MultiResolutionPDEDeformableRegistration<FixedImageType, MovingImageType, DisplacementFieldType> MultiResolutionRegistrationType;
typedef CommandResolutionLevelUpdate<MultiResolutionRegistrationType> LevelObserver;
typedef clitk::MultiResolutionPDEDeformableRegistration<FixedImageType, MovingImageType, DisplacementFieldType> MultiResolutionRegistrationType;
typedef CommandResolutionLevelUpdate<MultiResolutionRegistrationType> LevelObserver;