| -gaussian 1.7,8.4 | Gaussian kernel with the indicated sigma and maximum. | 
| -log 2.5,5 | Laplacian of gaussian kernel with the indicated sigma and maximum. | 
| -frequency 8,2 | Frequency space kernel: width and power. | 
| -verbose 7 | Verbosity of output. | 
| -size 5,7,9 | Size of kernel (voxels). |