Hi Anna, threshold initialization considers voxels either in or out the volume, while isosurface "cuts through" voxels using linear interpolation. So, with threshold you end up with a lego-brick like volume. However, this is only for initialization, i.e. the initial model before it evolves on image features. The two methods should lead to the same result after level set evolution. If you still get a blocky volume after evolution, it probably means you didn't specify a large enough number of iterations. Try increasing it considerably and see what happens. Best,
Luca On May 21, 2012, at 9:22 PM, Hoppe, Anna L wrote: > Hi vmtk users, > > I am using the vmtklevelsetsegmentation script for a segmentation. I have > used the threshold initialization type (with a lower limit of 2000 & no upper > limit) and the isosurface initialization type (with an isosurface level of > 2000) to obtain the segmented region that can be seen in the attached .jpgs. > However, the segmentation generated from the threshold initialization type > looks like it's striated (see threshold_segmentation_2000. jpg), as opposed > to the segmentation generated from the isosurface initialization type (see > isosurface_segmentation.jpg), which is what I would expect the surface I'm > segmenting to look like. Does anyone have any insights as to why the > threshold initialization type generates a striated reconstructed surface? > > Thank you for the help, > Anna<threshold_segmentation_2000.jpeg><isosurface_segmentation_2000.jpeg>------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. > http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/_______________________________________________ > vmtk-users mailing list > vmtk-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/vmtk-users ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ vmtk-users mailing list vmtk-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/vmtk-users
