SurfaceDistance[ref,pred]

gives the surface distance of segmentations ref and pred for class 1, assuming isotropic unit voxels. Use the vox argument for correct physical distances.

SurfaceDistance[ref,pred,class]

gives the surface distance for the given integer class.

SurfaceDistance[ref,pred,{class,..}]

gives the surface distance for each class in the list.

SurfaceDistance[ref,pred,class,vox]

gives the surface distance in millimeters using voxel size vox.

SurfaceDistance[ref,pred,{class,..},vox]

does the same for a list of classes. The Method option controls the distance metric: "Mean", "Median", "RMS", "HD", "HD95" (default), or "Std". A list of methods can be given to return multiple metrics at once.