[Insight-users] Confidence Connected (IKT) Irregularity?

[Wes Turner]

Charles,

I believe that the way this works is that at every iteration every point in
the current segmentation and neighborhood are evaluated against the current
mean and standard deviation.  Which means that as you progress a
segmentation can shrink as well as grow.  What you are seeing is exactly
that.  At first, when the variance is high, the segmentation brings in more
voxels.  Then as more voxels begin getting accumulated near the mean, the
variance decreases and previously acceptable voxels are discarded.  So, it
is behaving as designed.  WHether the design is correct is a different
discussion. :-)

- Wes

On Fri, Apr 1, 2011 at 8:47 AM, charles mac duff <charlesmcdff at gmail.com>wrote:

> Hi everyone,
>
>
>
> I notice that when I’m using the plug-in: Confidence connected of VolView
> 3.2, there’s something strange happening for certain set of parameters.
>
>
>
> When I set the number of iteration to 1 and the variance multiplier to 1
> (other parameters by default), the final segmented volume is bigger than
> when I put the number of iteration to 20 (with the same variance
> multiplier).
>
> Logically, at 20 iterations, the final segmented volume should be bigger
> because de growth has processed several times.
>
>
>
>
>
> Also, after a variance multiplier of about 1.5, the algorithm begins to
> work normally (more iterations we have, bigger the final segmented volume
> will be).
>
>
>
> So, I wonder what’s happening.
>
>
>
> Thank you very much in advance for your precious help,
>
>
> --
> Charles Mac Duff
>
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-- 
Wesley D. Turner, Ph.D.
Kitware, Inc.
Technical Leader
28 Corporate Drive
Clifton Park, NY 12065-8662
Phone: 518-881-4920
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