[Insight-users] Questions about MultiResMIRegistration application

[ask ITK]

Hi everyone,

      After reading some Insight Archives, there are still some points
confusing about the MultiResMIRegistration application package.
And I hope anyone can correct me.


The output of the application are:
1)
7 parameters: 4 for quarterion, and 3 for translation (T)

2)
A rotation matrix (R):
This matrix is formed by the 4 parameters of the quarterion.

3) Offset (OS)


I have read the software guide already and know that the offset is used
to compute the translation if the matrix is not applied to the image center.

However, I try to follow the software guide and the transformed
position of the image center is not correct.

I do this, for an image center C:
I compare
R*C+OS  (rigid transformation, center of rotation is corner of image)
with
C+T

The resulting position is different!!!!!

SO I WONDER actually what is the Final Translation of the Result??
the 3 translation parameters?????
OR
the offest ???????

Please help, I search severl pages in the web but seems no clear answer...
http://public.kitware.com/pipermail/insight-users/2004-September/010563.html

http://www.itk.org/pipermail/insight-users/2003-February/002593.html

http://www.itk.org/pipermail/insight-users/2002-April/000276.html