Thanks a lot!
what do you mean by iterative smoothing, is it heat kernel smoothing?
Attached is a paper about curvature of UCLA, in which I highlight some part of it.
firstly, they average the mean curvature within 3mm, then obtain its absolute value,
Then they further smoothed the absolute mean curvature using heat kernel smoothing.
I do not know what is the difference between averaging and iterative smoothing.
By the way, can I get the absolute value of a curv file using build-in function rather than load it into matlab and then write it back to binary files?
yczhang
Thanks
--- 09年6月1日，周一, Bruce Fischl <fischl@nmr.mgh.harvard.edu> 写道：
发件人: Bruce Fischl <fischl@nmr.mgh.harvard.edu>
主题: Re: [Freesurfer] A problem about average curvature value
收件人: "Zhangyuanchao" <woshizhangyc@yahoo.cn>
抄送: "freesurfer" <freesurfer@nmr.mgh.harvard.edu>
日期: 2009年6月1日,周一,下午10:36
Hi yczhang, yes, mris_average_curvature will do this on the surfae. It uses iterative averaging, but this converges to a Gaussian. Doug: can you post the formula that translates number of iterations into fwhm? thanks Bruce p.s. remember to include the -w switch otherwise it won't write out the results. On Mon, 1 Jun 2009, Zhangyuanchao wrote: > Is there any build-in function that I can average a curvature file with Radius of 4mm on the surface, for example, lh.pial.H.crv file. in addition, lh.curv are smoothed in some way, is it smoothed simply by averaging the values? > > Thanks! > > Best Regards, > yczhang > > > ___________________________________________________________ > ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ > http://card.mail.cn.yahoo.com/
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