<div><br></div>Hi Eliana,<div><br></div><div>Thanks for the clarifications.</div><div><br></div><div>You are indeed dealing with a very hard problem.</div><div>(and ill-posed one).</div><div><br></div><div>I have no new suggestions, different from what I mentioned </div>
<div>in my previous email.</div><div><br></div><div>I could simply reinforce that you want to make use of any</div><div>possible constrain you can add to this problem. (e.g. if you could</div><div>determine the range of tilts that the plane may have).</div>
<div><br></div><div>I know that people in this list has dealt with the similar problem</div><div>of registering 2D ultrasound images to 3D pre-operative images.</div><div>In that case, there is the advantage, of having some constrains</div>
<div>on the orientation of the Ultra-sound plane, and on having access</div><div>to the pixel values inside the object (organ), not just using values</div><div>from the boundary.<br><br></div><div><br></div><div><br></div>
<div> Regards,</div><div><br></div><div><br></div><div> Luis</div><div><br></div><div><br>-----------------------------<br><div class="gmail_quote">On Mon, Aug 17, 2009 at 6:10 AM, Eliana Vasquez Osorio <span dir="ltr"><<a href="mailto:e.vasquezosorio@erasmusmc.nl">e.vasquezosorio@erasmusmc.nl</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Hello Luis,<br>
Thank you for answering.<br>
It is a 2D manifold embedded in a 3D space. It's the surface of an<br>
organ (such as a kidney, liver, breast, etc...) and the contours are<br>
cuts on these organs.<br>
<br>
Any idea so far?<br>
Eliana<br>
<div><div></div><div class="h5"><br>
<br>
Luis Ibanez wrote:<br>
><br>
> Hi Eliana,<br>
><br>
> Is the Mesh a 2D mesh ?<br>
><br>
> That is, is embedded in a 2D space ?<br>
><br>
> or is the Mesh a 2D manifold embedded in a 3D space ?<br>
><br>
> (e.g. like the surface of a bone ?).<br>
><br>
><br>
> ---<br>
><br>
> Unless you have other constrains that can help,...<br>
> this is a very hard problem.<br>
><br>
><br>
> One option that you may want to consider is to<br>
> compute the curvature of the planar curve (e.g.<br>
> the radius of the osculating circle). An then in<br>
> the Surface compute the min and max curvature<br>
> at every point.<br>
><br>
> The curvatures of the planar curve (when matched<br>
> to the surface) will have to be inside the ranges of<br>
> the min and max curvatures of the matching points.<br>
><br>
> Another way to look at it, is that the internal angles<br>
> of your polygon should have to be in the range of<br>
> the dihedral angles of consecutive faces of the Mesh.<br>
><br>
> In that context, the easiest points to match will be the<br>
> points of the planar curve with the internal angles that<br>
> are farther from 180 degrees.<br>
><br>
> ....<br>
><br>
> In your email you ask if you could use Mesh to Image<br>
> registration methods.... Do you have the image from<br>
> which the Mesh was generated ?<br>
><br>
><br>
><br>
> Please let us know,<br>
><br>
><br>
> Thanks<br>
><br>
><br>
> Luis<br>
><br>
><br>
> ------------------------------------------------------------------<br>
> On Wed, Aug 12, 2009 at 11:29 AM, Eliana Vasquez Osorio<br>
</div></div>> <<a href="mailto:e.vasquezosorio@erasmusmc.nl">e.vasquezosorio@erasmusmc.nl</a> <mailto:<a href="mailto:e.vasquezosorio@erasmusmc.nl">e.vasquezosorio@erasmusmc.nl</a>>><br>
<div><div></div><div class="h5">> wrote:<br>
><br>
> Hello itk-users,<br>
> I'd like to register a contour (polygon composed by coplanar<br>
> lines) to a<br>
> mesh (set of triangles floating in the space).<br>
> The contour comes from a cut of the mesh, but the location of this cut<br>
> is not known. The idea is to find the plane that was used to create<br>
> this cut. I understand that for some cases the result is not unique,<br>
> such as using a perfect circle vs. an sphere, but just one<br>
> solution is ok.<br>
> I wonder if someone has done this, or something similar, before.<br>
><br>
> May be using ImageToSpatialObjectRegistrationMethod or<br>
> PointSetToImageRegistrationMethod ???<br>
><br>
> Any idea/suggestion etc is welcome!<br>
><br>
> Thanks, Eliana<br>
><br>
><br>
><br>
><br>
> --<br>
> Eliana M. Vásquez Osorio<br>
> PhD Student (OIO)<br>
> Erasmus Medical Center - Daniel den Hoed Cancer Center<br>
> Department of Radiation Oncology<br>
> Groene Hilledijk 301<br>
> 3075 EA Rotterdam<br>
> The Netherlands<br>
><br>
> T: +31 10 70 41 491<br>
> F: +31 10 70 41 012<br>
> E-mail: <a href="mailto:e.vasquezosorio@erasmusmc.nl">e.vasquezosorio@erasmusmc.nl</a><br>
</div></div>> <mailto:<a href="mailto:e.vasquezosorio@erasmusmc.nl">e.vasquezosorio@erasmusmc.nl</a>><br>
><br>
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<br>
<br>
</div>--<br>
<div><div></div><div class="h5">Eliana M. Vásquez Osorio<br>
PhD Student (OIO)<br>
Erasmus Medical Center - Daniel den Hoed Cancer Center<br>
Department of Radiation Oncology<br>
Groene Hilledijk 301<br>
3075 EA Rotterdam<br>
The Netherlands<br>
<br>
T: +31 10 70 41 491<br>
F: +31 10 70 41 012<br>
E-mail: <a href="mailto:e.vasquezosorio@erasmusmc.nl">e.vasquezosorio@erasmusmc.nl</a><br>
<br>
</div></div></blockquote></div><br></div>