AFNI Message Board

Dear AFNI users-

We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:

https://discuss.afni.nimh.nih.gov

Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.

The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.

Sincerely, AFNI HQ

History of AFNI updates  

Previous Message Next Message
Message List New Topic Print View
|
Daniel Glen
October 23, 2009 04:52PM
You can also use 3dLocalstat to make a kind of dilated blob. In this example, 3dLocalstat is used to look at a 2 voxel neighborhood in x and y for each voxel. A sum is computed at each voxel over its neighborhood, then any voxel with any neighbors at all in the neighborhood is given a value of 1 using 3dcalc.

3dLocalstat -nbhd 'RECT(-2,-2,0)' -stat 'sum' -prefix localstat_sum_am2 periphery_am2+orig

3dcalc -a localstat_sum_am2+orig. -expr 'step(a)' -prefix localstat_dilate2

The attached image shows the result of dilating a 1 voxel thick ROI with a 2 voxel neighborhood. This can be used in 3D and with spheres too.
Reply Quote
RSS
Subject Author Posted

dilating a blob

Jed Meltzer October 22, 2009 05:26PM

Re: dilating a blob

rick reynolds October 22, 2009 05:59PM

Re: dilating a blob

Daniel Glen October 23, 2009 04:52PM