<br>Hi Jihan,<br><br>In the Speed image the Zero values represent borders<br>of the object to be segmented, and the One values<br>represent the inside of the object.<br><br>Please note that the Speed image is NOT the segmentation,<br>
it is only the map of where the LevelSet will be allowed <br>to grow.<br><br>The inside of the LevelSet will be the segmentation.<br><br>Strictly speaking, what you need is the speed image to<br>be non-zero inside of the object, and to have "close to"<br>
zero values in the borders, so that the LevelSet propagation<br>will be stopped there.<br><br>The values outside of the object could be set to any other<br>value...<br><br>In practice, what tend to happen is that the border of the<br>
object is not exactly zero in the speed image, and therefore<br>the Levelset manage to go through the border and "leak"<br>to the outside of the object.<br><br>All this will be clearer if you study the images in the <br>
ITK Software Guide, in the LevelSet section.<br><br><br> Regards,<br><br><br> Luis<br><br><br>----------------------------<br><div class="gmail_quote">On Wed, Jul 1, 2009 at 7:11 PM, Jihan Zoghbi <span dir="ltr"><<a href="mailto:jihanzoghbi@gmail.com">jihanzoghbi@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi Luiz,<br><br>Thank you for the answer. The values of 1.0 and 0.0 represent the object to be segmented or the whole image, where we have Zeros in the borders and 1 inside the borders of the objects in the image?<br>
best regards.<br>
<br><br><div class="gmail_quote">2009/7/1 Luis Ibanez <span dir="ltr"><<a href="mailto:luis.ibanez@kitware.com" target="_blank">luis.ibanez@kitware.com</a>></span><div><div></div><div class="h5"><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>Hi Jihan,<br><br>This is done because we are computing a Speed image.<br><br>The ideal speed image have Zero values in the borders<br>of the object that you are segmenting, and have 1.0<br>values inside the object, in order to facilitate the rapid<br>
propagation of the LevelSet.<br><br><br> Regards,<br><br><br> Luis<br><br><br>-------------------------------------------------------------------------<br><div class="gmail_quote"><div><div></div><div>
On Wed, Jul 1, 2009 at 4:06 PM, Jihan Zoghbi <span dir="ltr"><<a href="mailto:jihanzoghbi@gmail.com" target="_blank">jihanzoghbi@gmail.com</a>></span> wrote:<br>
</div></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div><div></div><div><br clear="all">Hi everybody,<br><br>Anyone knows why in the file GeodesicActiveContourImageFilter.cxx the values of the MIn and Max values are 0.0 and 1.0 respectively as follows?<br>
sigmoid->SetOutputMinimum( 0.0 );<br>
sigmoid->SetOutputMaximum( 1.0 );<br>-<br>Thanks<br><font color="#888888">Jihan Zoghbi<br><br>
</font><br></div></div>_____________________________________<br>
Powered by <a href="http://www.kitware.com" target="_blank">www.kitware.com</a><br>
<br>
Visit other Kitware open-source projects at<br>
<a href="http://www.kitware.com/opensource/opensource.html" target="_blank">http://www.kitware.com/opensource/opensource.html</a><br>
<br>
Please keep messages on-topic and check the ITK FAQ at: <a href="http://www.itk.org/Wiki/ITK_FAQ" target="_blank">http://www.itk.org/Wiki/ITK_FAQ</a><br>
<br>
Follow this link to subscribe/unsubscribe:<br>
<a href="http://www.itk.org/mailman/listinfo/insight-users" target="_blank">http://www.itk.org/mailman/listinfo/insight-users</a><br>
<br></blockquote></div><br>
</blockquote></div></div></div><br><br clear="all"><br>-- <br><font color="#888888">Jihan Zoghbi<br><br>
</font></blockquote></div><br>