[Insight-users] looking for Watershed Boundary example

[Joshua Cates]

Hi Rémi,

Have you experimented with the Threshold parameter on the watershed 
filter?  This controls thresholding of low values in the input image, 
which is designed to suppress small catchement basins.  The value is 
expressed as a percentage of the maximum height in the input image.

Josh.



______________________________
 Josh Cates			
 School of Computer Science	
 University of Utah
 Email: cates at sci . utah . edu
 Phone: (801) 587-7697
 URL:   http://www . sci . utah . edu/~cates


On Fri, 6 Jun 2003, SERIOT Rémi        DEC/SPUA/LTEC wrote:

> Hi Josh,
> 
> Thanks for your help, I've got outlines of  my watershed labeled region. But
> I have another question for you. 
> my application looks like your example
> (http://www . cs . utah . edu/~cates/watershed/) so I can adjust the flood level
> of itk::RelabelWatershedImageFilter for create a good segmentation of my
> image. But now I would like to suppress small catchments basins in my
> labeled image. Actually it would be great if I could adjust the value of the
> smallest catchments basins in order to create an optimum segmentation.
> 
> Thanks for your help!
>  
> Rémi
>  
> 
> > -----Message d'origine-----
> > De : Joshua Cates [mailto:cates at sci . utah . edu]
> > Envoyé : lundi 2 juin 2003 18:12
> > À : SERIOT Rémi DEC/SPUA/LTEC
> > Cc : 'insight-users at public . kitware . com'
> > Objet : Re: [Insight-users] looking for Watershed Boundary example
> > 
> > 
> > Hi,
> > 
> > The watershed::Boundary and BoundaryResolver are actually only used to
> > resolve global connectivities from local computations during streaming
> > applications.  So the meaning of "boundary" in this case is 
> > different from
> > what you need.  I don't know of any quick way to generate 
> > outlines of the
> > labeled regions in ITK.  The 
> > Examples/Segmentation/WatershedSegmentation1
> > may give you some other ideas for visualization.  To generate 
> > outlines,
> > you may need to write your own code, but it shouldn't be 
> > difficult. Keep 
> > in mind, however, that boundaries are actually between pixels.
> > 
> > Josh.
> > 
> > ______________________________
> >  Josh Cates			
> >  School of Computer Science	
> >  University of Utah
> >  Email: cates at sci . utah . edu
> >  Phone: (801) 587-7697
> >  URL:   http://www . sci . utah . edu/~cates
> > 
> > 
> > On Mon, 2 Jun 2003, SERIOT Rémi        DEC/SPUA/LTEC wrote:
> > 
> > > Hello everybody
> > > 
> > > I'm developing an example in order to segmentate an image 
> > with the watershed
> > > algorithm. I already write the code for create a labeled image, with
> > > itk::watershed::WatershedSegmenter, 
> > itk::watershed::SegmentTreeGenerator and
> > > itk::watershed::Relabeler with the value of flood level. 
> > > But now I would like to draw the boundary of each segmented 
> > regions, I try
> > > to use itk::watershed::Boundary and BoundaryResolver but I 
> > can't find any
> > > good example.
> > > 
> > > I'm a novice in itk so any suggestions or any example of 
> > watershed::Boundary
> > > and BoundaryResolver will be appreciate
> > > 
> > > Thanks for your help!
> > > 
> > > Rémi
> > > _______________________________________________
> > > Insight-users mailing list
> > > Insight-users at public . kitware . com
> > > http://public . kitware . com/mailman/listinfo/insight-users
> > > 
> > 
>