Hi Dan, Thank You for your reply. I looked at Fast Marching minimization. It works for 2d images. What, I have here is 3d data. Thank You Charu -- View this message in context: http://itk-insight-users.2283740.n2.nabble.com/Centerline-tp7507501p7509617.html Sent from the ITK Insight Users mailing list archive at Nabble.com.