For the Scale function, you can choose between Tri-Linear or Nearest Neighbor interpolation. Both are methods of multivariate interpolation in one or more dimensions.

Boxel Lengths refer to the current lengths in the structure model, in the three directions. These values are automatically entered from the Voxel Length defined by the user at the bottom of the Import Images dialog.

For FIB-SEM scans, for example, the length in Z-direction usually differs from the other two directions and corresponds to the spacing between images. This spacing is defined during the acquisition of the FIB-SEM images and should be included as data with the image files. Importing the stack directly, without accounting for the spacing distortion, results in a stacked structure, which does not replicate the original scanned one.

To account for this spacing distortion, enter the length in Z-direction and click Apply. GeoDict only scales the voxels in that direction and completes the missing slices to make a uniform object. The size of the scaled object shown as NX, NY, and NZ in the Crop panel changes accordingly to reflect the fill-in.

The Re-sampled Length value is used to re-sample the physical structure size (voxel length) uniformly in all directions with a grid adapted to the re-sampled length value and, thus, coarsen or refine the imported structure.

In the following example observe the difference between the two options for the Scale Function. While the resulting number of voxels is the same for both options, Tri-Linear additionally interpolates gray-values for a smoother transition.