[Insight-users] Correct use of MRIBiasFieldCorrectionFilter ?

[karmonik]

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Hi there,

I am using the MRIBiasFieldCorrectionFilter to correct the bias field of a MRI 
surface coil (see attached image).

The class itself works fine, I am able to input and output all the 
parameters,the image and the masks.

However, so far I was not able to obtain a good correction. The estimated bias 
field is incorrect. So, I must be doing something wrong. (The filter finds 
local minima instead of the global minimum).

Could anybody suggest good values for cshrink, cgrow, x0 as well as the 
coefficients for the legendre polynoms? I tried without success the parameter 
value ranges suggested in the references.

Does anybody have experience with this filter?

Is it possible to use a basis set other than the Legendre Polynoms (i.e. 
Gaussians?)

It would be a pity if this elegant correction algorithm only worked for the 
examples given in the two references ....

Thanks

Christof

Christof Karmonik, PhD
Baylor College of Medicine/The Methodist Hospital
Mailstation M217
6565 Fannin
Houston, TX 77030
Pager: (713) 708-2232
Fax: (713) 790-4688

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