[vtkusers] How to eliminate points under threshold

[YaoHaofeng]

Hi,I have an 3d image which is a brain and the air surrounding it when scanned, when I render the data on the window, it gives me a red cube, which should be the air, and I cannot see the brain, how can I tell vtk not to render the air voxels and show only the brain voxels? I guess one way to do it using thresholding, but I am not quite sure, please help.thankshank 
_________________________________________________________________
中国十大热门旅游景点
http://search.msn.com/results.aspx?q=%E4%B8%AD%E5%9B%BD%E5%8D%81%E5%A4%A7%E9%A3%8E%E6%99%AF&mkt=zh-CN&form=QBRE
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20070308/58d58f3f/attachment.htm>