Greetings,
I'm a new researcher in DTI field and my project needs to match the estimated motion parameter (6-DOF: x,y,z,roll,yaw,pitch) to the real motion in XYZ coordinate of scanner. I've read the lecture about FLIRT but still it didn't solve my questions. I'd be very gratful if someone could help me out.
1, What's the coordinate system in which the estimated 6-DOF motion parameter defined?
The lecture mentioned voxel space coordinate which can make the problem become a pure 3D matrix. However, it requires voxel size so I think it might jump between voxel space coordinate and standard space coordinate.
2, How does this coordinate system related to the input NFITI 3D data?
In either coordinate system I found in the lecture, the definition of coordinate is corelated to the image data coordinate. For example, the voxel space coordinate defines origin at lower-left corner. Then what's the lower-left cornner in the NIFTI 3D data? Is that the same lower-left corner if I read the 3D NFITI by spm_read_vols?
3, This is a little bit extension about FDT. What's the assumption of coordinate of the input bvecs? Is it XYZ ?
FSL does a wonderful job about fiber tracking so I believe there must be some understandable transformation from real world to estimated motion parameters.
Thank you veryone who read this message. Any help from you is highly appreciated.
Best regards,
Xiaowei Zou
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