Joint smooth in 2d

Hi,

The joint smoothening tool historically works very well for me, but now I have a series of atlas segments that are very poorly sampled in Z. The X Y edges are also rather rough, and so I want to improve these by upsampling the segmentations and then joint smoothen. I know how to do this part, and it has worked well in the past with higher Z sampled images, but now the abrupt jumps in Z make the joint smoothen tool do odd things. Is there a simple set of commands to run this tool in 2D, i.e., in each plane of Z?

p.s., One hack I did was to inflate the volume with replicate images (e.g, z x 10), which improved the outcome, but this seems like waste of resources and it still misbehaved for this odd use case.

Thanks,
Steve