Hi Chengcheng, it occurred to me that probably you need an extra piece of the pipe:
vmtkimagecompose -ifile image.vti -i2file image.vti --pipe vmtkimagecompose -i2file image.vti -negatei2 1 --pipe vmtkimageshiftscale -mapranges 1 -outputrange 0.0 100.0 -ofile negated_image.vti This way your output will be positive everywhere. Luca On Nov 10, 2010, at 11:16 PM, Luca Antiga wrote: > Hi Chengcheng, > the segmentation itself makes no assumptions on the fact that the lumen is > brighter > than the outside, however the initialization - like colliding fronts and fast > marching - does > by default. A trivial way to go around this is to negate the image before > running the segmentation. > There's actually no script in vmtk to do that, but this pipe should do the > trick: > > vmtkimagecompose -ifile image.vti -i2file image.vti --pipe vmtkimagecompose > -i2file image.vti -negatei2 1 -ofile negated_image.vti > > I just added a switch to vmtkimageinitialization that allows to negate the > image while initializing. > > I'm curious to see if this helps, please keep me posted. > > Best regards > > > Luca > > > On Nov 10, 2010, at 7:08 PM, Chengcheng Zhu wrote: > >> Hi, >> >> I have tried to segment carotid artery bifurcation using black-blood >> T1 or T2 weighted MR images, but the result was very bad. However, it >> works quite well on time-of-fight MR images. Does the vessel must be >> bright (hyperintense) for VMTK to segment? Thank you. >> >> Best Wishes >> >> Chengcheng >> >> ------------------------------------------------------------------------------ >> The Next 800 Companies to Lead America's Growth: New Video Whitepaper >> David G. Thomson, author of the best-selling book "Blueprint to a >> Billion" shares his insights and actions to help propel your >> business during the next growth cycle. Listen Now! >> http://p.sf.net/sfu/SAP-dev2dev >> _______________________________________________ >> vmtk-users mailing list >> vmtk-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/vmtk-users > ------------------------------------------------------------------------------ Centralized Desktop Delivery: Dell and VMware Reference Architecture Simplifying enterprise desktop deployment and management using Dell EqualLogic storage and VMware View: A highly scalable, end-to-end client virtualization framework. Read more! http://p.sf.net/sfu/dell-eql-dev2dev _______________________________________________ vmtk-users mailing list vmtk-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/vmtk-users
