Hi Ray
the -1 means that the target is a single surface and not an atlas, but the registration is still nonlinear. The variances will all be 1 so you may have to play with the weights in the energy functional. We don't do this very much and it probably defaults to quite rigid. Try reducing the weight on the metric preservation term (e.g. -dist .25) if you want it to be more nonlinear
cheers Bruce
On Tue, 3 Nov 2015, Razlighi, Qolamreza R. wrote:
Hi Guys, I read in the sidenote here (https://surfer.nmr.mgh.harvard.edu/fswiki/SurfaceRegAndTemplates) that inter-subject surface base registration using mris_register and -1 flag performs a sort of rigid registration. So I tried it between two of my subjects with the command below
mris_register -1 -curv P00001639/FreeSurferClean/surf/lh.sphere P00001639/FreeSurferClean/surf/lh.sphere lh.sphere3.reg
and got the results (see the attachment). It is clear that the registration output is just a shifted version of the source. Having this confirmed I want to know if there is any way to force the mris_register to perform a complete non-linear surface based registration for inter-subjects registration the same way it does for template.
I have to mention that I visualize the lh.sphere3.reg using freeview and loaded the sane lh.curv on that surface. I hope I’m not doing anything stupid.
[IMAGE]
Best -- Ray Razlighi, Ph.D. Assistant Professor Quantitative Neuroimaging Laboratory Division of Cognitive Neuroscience Department of Neurology Columbia University
Alt: razlighi@gmail.com Office Phone: 212-342-1352 Office Fax: 212-342-1838 Website: http://www.columbia.edu/cu/qnl/