Yes, I see what you mean now. Currently, there is nothing that vol2surf does to account for this. One thing that can be done is to super-sample the mesh so make the distance between vertices smaller (this is what Jon Pollemeni does -- and he's certainly working at fMRI resolutions where this kind of thing matters).
doug Aaron Alexander-Bloch wrote: > Dear Doug > Thanks for your response. What I meant is, for example, some voxels > would be "occupied" by edges of the mesh even if they are not occupied > by any vertices. As you move to higher and higher resolutions, > presumably more and more voxels would fall into this category. That > being said, I understand that on average this shouldn't affect the > output very much. > Best > Aaron > > On Mon, Feb 14, 2011 at 2:51 PM, Douglas N Greve > <gr...@nmr.mgh.harvard.edu> wrote: > >> It does not take into account any info about the faces or edges. I'm not >> sure about your resolution question. Can you elaborate? >> doug >> >> Aaron Alexander-Bloch wrote: >> >>> Dear all, >>> >>> I am hoping to use surf2vol to generate high resolution masks of the >>> gray/white surface, so something like the following command: >>> >>> mri_surf2vol --sd /subj/dir/ --identity subid --hemi lh --surf white >>> --mkmask --o volume.mgz --template ./template.mgz >>> >>> However I'm wondering about what exactly the algorithm does. I >>> understand that the vertices are placed at the closest voxel in the >>> template space. But does the algorithm take into account information >>> about the faces/lines of the mesh in addition to the vertices? If so, >>> how? If not, does that imply a limit to the resolution of the template >>> space that should be used with the command? >>> >>> Thanks very much in advance for any help. >>> >>> Best, >>> Aaron Alexander-Bloch >>> PhD student, University of Cambridge >>> _______________________________________________ >>> Freesurfer mailing list >>> Freesurfer@nmr.mgh.harvard.edu >>> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer >>> >>> >>> >>> >> -- >> Douglas N. Greve, Ph.D. >> MGH-NMR Center >> gr...@nmr.mgh.harvard.edu >> Phone Number: 617-724-2358 Fax: 617-726-7422 >> >> Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting >> FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html >> >> >> >> The information in this e-mail is intended only for the person to whom it is >> addressed. If you believe this e-mail was sent to you in error and the >> e-mail >> contains patient information, please contact the Partners Compliance >> HelpLine at >> http://www.partners.org/complianceline . If the e-mail was sent to you in >> error >> but does not contain patient information, please contact the sender and >> properly >> dispose of the e-mail. >> >> >> > > > -- Douglas N. Greve, Ph.D. MGH-NMR Center gr...@nmr.mgh.harvard.edu Phone Number: 617-724-2358 Fax: 617-726-7422 Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
