Hi,
  I'm working on a project for 3D vascular structure segmentation and characterization. I found that the Vaa3D MOST plugin works very well for the segmentation(original file is 600*600*700 tiff stack).
  I read relevant publication and learned the plugin is using voxel scooping for centerline tracing, but I don't understand how segmentation of the vessels is done. For instance how does the plugin extract tubular structure from a noisy image. Also is it possible to just display the centerline. It would be really helpful if you can share more detail regarding the algorithm of this plugin.
  Another question is about the size of the mask. I tried to convert the mask from swc to image file, but the size of the mask is not the same as the original image. I am not sure what is the reason for this and how to solve it. 
  Thank you very much for your help and patience.