Hi AFNI team,

I have a unique issue and I was wondering if I could have some guidance with how to approach it with AFNI's tools.
I am trying to create a probabilistic atlas of certain sulci I am interested in, and have been able to create NIFTI files with each subject's binary representation of the sulci (i.e. the location of the sulci have a voxel value of 1). From here, the next step would be to add all the subject's sulci maps together so that the resulting map (the addition of the binary images) is a heat map with greatest intensity where the sulci are most prominent. The subjects were all normalized and the sulci should be in the same space, however the program I am using (BrainVISA morphologist) will output each subject's sulci map with slightly different dimensions (e.g. 161x198x161 versus 162x200x158). I'm not sure why the program does this (possibly it restricts the image to just where the sulci are, so the dimensions are reflective of subject specific extents of sulci), but as you can imagine, this makes this heat-map/addition procedure much more complicated. Sulci maps are not too informative relative to full structural T1 scans, so affine transformations and registering each sulci map to a reference image may create issues. Any suggestions on how I may approach this issue while retaining an accurate resulting heat map would be greatly appreciated and will be of great help to my project.

Best,
Will Snyder