[Insight-users] itkConstNeighborhoodIterator and degenerate regions (was RE: [Ins ight-users] Degenerated volumes question)

[Joshua Cates]

Thanks for fixing this.

Josh.


On Tue, 26 Aug 2003, Miller, James V (Research) wrote:

> Josh,
> 
> I put in a change to ConstNeighborhoodIterator::SetEndIndex() (which is
> called 
> by Initialize()) such that if a region has no pixels (because one of the
> components
> of the size is zero), then the EndIndex is set to the BeginIndex.  This
> ensures
> that IsAtEnd() is immediately satisfied on regions that have no pixels.
> 
> This will address a number of number of crashes when a face from the face
> calculator 
> has no pixels.
> 
> Jim
> 
> > -----Original Message-----
> > From: Miller, James V (Research) [mailto:millerjv at crd . ge . com]
> > Sent: Tuesday, August 26, 2003 4:05 PM
> > To: 'Benjamin King'; Luis Ibanez; ITK
> > Cc: Josh Cates (E-mail)
> > Subject: RE: [Insight-users] Degenerated volumes question
> > 
> > 
> > Benjamin,
> > 
> > I ran your test and it crashed for me.  Thanks for pulling 
> > this together.
> > I changed the line of code in the MorphologyImageFilter that 
> > I suggested
> > and your program does not crash for me anymore.
> > 
> > I checked in the change.  However, this does illustrate we 
> > have a bug in the
> > 
> > NeighborhoodIterators when they are told to walk a region that has no
> > pixels.
> > The IsAtEnd condition should be immediately satisfied in this 
> > case. I'll
> > start
> > looking at that next.
> > 
> > Thanks.
> > Jim
> > 
> > > -----Original Message-----
> > > From: Benjamin King [mailto:king . benjamin at mh-hannover . de]
> > > Sent: Tuesday, August 26, 2003 11:51 AM
> > > To: Miller, James V (Research); Luis Ibanez; ITK
> > > Subject: Re: [Insight-users] Degenerated volumes question
> > > 
> > > 
> > > Hello James and Luis,
> > > 
> > > thank you for your quick replies! I have attached code and 
> > data that 
> > > demonstrate the problem. The name of the image is hardcoded 
> > into the 
> > > program and I have added hopefully useful comments. In the 
> > > current setup, I 
> > > get a segfault for region 13. I also included a pad filter 
> > > and if just some 
> > > minimal padding is added then the program runs just fine. The 
> > > try-catch 
> > > block doesn't reveal anything, so I think that it's really a 
> > > segmentation 
> > > fault.
> > > 
> > > > Just saying
> > > > you have a bug with small regions in ITK is not a very 
> > > graceful way to
> > > > report a bug.
> > > 
> > > =D
> > > 
> > > 
> > > Best regards,
> > >   Benjamin
> > > 
> > > 
> > > -- 
> > > Benjamin King
> > > Institut fur Medizinische Informatik
> > > Medizinische Hochschule Hannover
> > > Tel.: +49  511  532-2663
> > > 
> > _______________________________________________
> > Insight-users mailing list
> > Insight-users at itk . org
> > http://www . itk . org/mailman/listinfo/insight-users
> > 
> _______________________________________________
> Insight-users mailing list
> Insight-users at itk . org
> http://www . itk . org/mailman/listinfo/insight-users
>