it uses a spherical parameterizations (longitude and colatitude) to generate averages, then samples the results onto an icosahedron.
cheers, Bruce On Wed, 31 Jan 2007, XJ Kang wrote:
Hi,
I am trying to genearate average surface curvature map from ?h.sphere.reg.
One way I did is using make_average_subject. I got both volume and surface avareges. I also created a surface using my own method: resample the surface maps ?h.sphere.reg to a common spherical coordinates (th, phi), and calculate the averages of all spheres. The average surface map I got is somewhat different from the result of "make_average_subject". Can somebody tell me the rough procedure of mris_make_average_surface?
As far as I know from the FreeSurfer docs, mris_make_average_surface averages a set of surface coordinates and generate an average surface using Talairach coordinates and spherical transform. For the spherical average, does it resample the individual spheres to a common spherical coordinates and average them?
Thanks.
XJ Kang _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer