After saving segmentations and labels, I have noticed that sometimes certain structures change to a lower resolution. Not all segmentations change to a lower resolution, just some, but it is always the same structures. I am wondering if anyone knows why this is or if anyone has tips or suggestions to prevent this.
In a segmentation with binary labelmap representation, each layer is allowed to have different geometry (origin, spacing, axis directions, extents) temporarily - to allow moving segments between segmentations without unnecessary quality loss (each resampling of a binary labelmap can lead to slight changes). All layers are forced to have the same geometry during certain editing operations and when the segmentation is saved to file.
I didn’t know this. Is it documented under what conditions this happens? Since uniformity is forced on saving, shouldn’t it be forced when a segment is transferred into a different segmentation? What is the use case where allowing the temporary altered resolution, but forcing it on saving, avoids unnecessary resampling? The only case I can think of is if you have a high resolution segment in segmentation A, copy it to lower resolution segmentation B, and then copy it again from segmentation B to segmentation C, which has a different low resolution, but I’m not sure when someone would routinely be doing that.