<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;"><div><br></div>To use the SignedDanielssonDistanceMap just pipeline the result of the distance map<div><br></div><div>filter to the level set filter instead of the fastMarching filter. If you already have done that</div><div><br></div><div>double check your distance map settings then try to change the InsideIsPositive() property</div><div><br></div><div>of the distance map filter which could be the source of the problem.</div><div><br></div><div>The Chan-Vese level set segmentation is already supported by the ITK, for more information</div><div><br></div><div>take a look at the following links,</div><div><br></div><div><a href="http://www.insight-journal.org/browse/publication/642">http://www.insight-journal.org/browse/publication/642</a></div><div><br></div><div><a
href="http://www.itk.org/Doxygen/html/classitk_1_1ScalarChanAndVeseDenseLevelSetImageFilter.html">http://www.itk.org/Doxygen/html/classitk_1_1ScalarChanAndVeseDenseLevelSetImageFilter.html</a></div><div><br></div><div>Best regards,</div><div><br></div><div>Dawood</div><div><br></div><div><br>--- On <b>Wed, 2/16/11, Ella Maria Kadas <i><ella_kadas@yahoo.com></i></b> wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"><br>From: Ella Maria Kadas <ella_kadas@yahoo.com><br>Subject: RE: GeodesicActiveContours processing time and SignedDanielssonDistanceMap<br>To: "Dawood Masslawi" <davoud_zzz@yahoo.com><br>Date: Wednesday, February 16, 2011, 10:27 AM<br><br><div id="yiv1026700954"><table cellspacing="0" cellpadding="0" border="0"><tbody><tr><td valign="top" style="font:inherit;">Hi Danwood,<div><br></div><div> Thanks a lot. No, i was not going to use both of them, i was just
saying that i would have liked to try to initialize the level set using SignedDanielsssonDistanceMap, but i didn't manage to get it work.</div><div>Thanks for the links i will have to tune the parameters then to make it work for my images.</div><div>I will maybe play first with the ITK Snap.</div><div>Do you know if there is already the Chan-Vese Method using the Level Set Framework as filter for 3D segmentation implemented.?</div><div>Thanks again,</div><div>Ella</div><div><br><br>--- Dawood Masslawi <i><davoud_zzz@yahoo.com></i> schrieb am <b>Mi, 16.2.2011:<br><blockquote style="border-left:2px solid rgb(16, 16, 255);margin-left:5px;padding-left:5px;"><br>Von: Dawood Masslawi <davoud_zzz@yahoo.com><br>Betreff: RE:
GeodesicActiveContours processing time and SignedDanielssonDistanceMap<br>An: ella_kadas@yahoo.com<br>CC: insight-users@itk.org<br>Datum: Mittwoch, 16. Februar, 2011 15:53 Uhr<br><br><div id="yiv1026700954"><table cellspacing="0" cellpadding="0" border="0"><tbody><tr><td valign="top" style="font:inherit;">Hi Ella,<div><br></div><div>You don't need to use the fastMarching filter if you are using the DanielssonDistanceMap</div><div><br></div><div>and vice versa.</div><div><br></div><div>If you want to lower the computation time you can decrease the number of iterations or </div><div><br></div><div>assign lower values for the maximum allowed RMS.</div><div><br></div><div>The initialDistance parameter is the distance between the seed points and the desired</div><div><br></div><div>initial contour.</div><div><br></div><div>Also, the following posts on the mailing list can give you more information on how
to</div><div><br></div><div>control the level of details in your segmentation.</div><div><br></div><div><a rel="nofollow" target="_blank" href="http://www.itk.org/pipermail/insight-users/2011-February/039551.html">http://www.itk.org/pipermail/insight-users/2011-February/039551.html</a></div><div><br></div><div><a rel="nofollow" target="_blank" href="http://www.itk.org/pipermail/insight-users/2011-January/039435.html">http://www.itk.org/pipermail/insight-users/2011-January/039435.html</a></div><div><br></div><div>Note that the assigned Alpha and Beta values for the sigmoid filter can have a significant</div><div><br></div><div>effect on the results. It is best to choose the Beta close to the initial contour value and </div><div><br></div><div>assign the Alpha in which an acceptable range of values around the Beta would be</div><div><br></div><div>mapped.</div><div><br></div><div>Best
regards,</div><div><br></div><div>Dawood</div><div><br></div><div><br></div><div>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</div><div><br></div><div>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</div><div><br></div><div><br></div><div><span class="yiv1026700954Apple-style-span" style="font-family:'Times New Roman';font-size:medium;"><pre>Hi,
I managed to start run the GeodesicActiveContoursFilter. I forgot to the line
fastMarching->SetOutputSize(reader->GetBufferedRegion().GetSize());.
I wanted to use the SignedDanielssonDistanceMapFilter, but i get the same problem as before putting the line above as a result.
Is there something similar for the SignedDanielssonDistanceMapFilter to set?
My second question is regarding the time used for the segmentation
I tried to use it on a MRI t2_3D, 256 slices 40 Iteration steps, but it took me more then 4 minutes. Is this a normal behaviour that i should expect on Leopard 10.6 16 GB RAM?
I still think i am missing something because i don't see a connection between the image and the segmented region. (Which leads me to my third question, what does the DistanceValue in the fastMarching means- it just doesn't make sense to me when starting with a seed point only and not with some initial contour).
I send some images maybe this will help to help me:P
i didn't put all of them, but Test4 is the one where i put my seed point.<a rel="nofollow" target="_blank" href="https://picasaweb.google.com/ellaMkadas/TestLevelSet?authkey=Gv1sRgCMrzgp3nsPfWeg#">https://picasaweb.google.com/ellaMkadas/TestLevelSet?authkey=Gv1sRgCMrzgp3nsPfWeg#</a>
Thanks,
Ella</pre></span></div></td></tr></tbody></table><br>
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