I want to do a 3d volume of a structure (e.g. kidney) of an image volume, but I need to threshold across the kidney at different threshold intensities. unfortunately, the threshold applies to the 3d volume the same intensity across all slides. is there a way to do this in an efficient manner, versus making a different segmentation for each image slice?
Indeed, simple global thresholding only works well in a few special cases (such as bone segmentation in CT). That is why we added several other semi-automatic segmentation methods that rely on local intensity changes only. The most commonly used is Grow from seeds, but you can also try Local threshold, Fast marching, Watershed, or Flood filling methods (in SegmentEditorExtraEffects extension).