[Insight-users] Question about ThresholdSegmentationLevelSetFltkGui

[Luis Ibanez]

Hi Chunyan,

This applications expects you to provide a *region*
as initialization, not a contour.  Instead of a band,
you should draw a more solid figure trying to fill the
inside of the anatomical structure that you want to
segment. The boundaries of this solid figure will be
propagated as the zero set of the level set.

The two red contours that you are seeing right now are
indeed the boundaries of the band that you draw, and
it is not really two contours but a single one that goes
continuously around your band.

It is easier to draw solid figures in this application
if you use a larger "Brush Size" in the option "Draw
initial Segmentation".

You may find this clearer is you get more familiar with
the concepts behind the use of Level Set methods. You
may want to start by reading from the SoftwareGuide

   http://www . itk . org/ItkSoftwareGuide . pdf


Section 9.3, pdf-pages 363.

If you want a more theoretical description, you should
look at the book by Sethian:

     "Level Set Methods and Fast Marching Methods"
     J.A. Sethian,
     Cambridge University Press.
     ISBN: 0-521-64557-3


If you want to post more specific question regarding
your images you are encourages to create an account
in MyPACS and post the image there:

             http://www . mypacs . net

You can create and account for free, and also have access
to public images that other MyPacs users are sharing.

Once you upload your images, simply let us know the
identification number the image. This is much simpler than
attempting to describe the image verbally.


Please let us know if you have further questions.


Thanks


    Luis


--------------------------
jiang wrote:
> Hi Luis,
> I tried the application ThresholdSegmentationLevelSetFltkGui. It is very
> nice application. I can handle some very complex segmentation task. I have a
> question about this application:
> When I use draw an initial segmentation in Level-Set Initialization panel,
> it draws a semi-transparent band on the imported image. And when the
> Segmentation starts, there are two red contour lines come from the band,
> which propagate at the same time. I want to know why it has two fronts in
> this method? Which strategy does it use?
> 
> Thank you very much!
> 
> Happy new year!
> 
> Chunyan
> 
> _______________________________________________
> Insight-users mailing list
> Insight-users at itk . org
> http://www . itk . org/mailman/listinfo/insight-users
>