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<br>When i work with images of brain which hardly has any non-rigid component in it, i use affine transformation. However, most of the other organs need non-rigid transform and hence we use non-rigid transform for the whole image. If there are regions that undergoes only a rigid transform, the resulting deformation field should confirm that. <br><br>Is it possible for you to crop the image into 2 regions - one that can undergo only rigid transform and another that has all the degrees of freedom to transform? That way, you would have absolute assurance that the rigid organ has a rigid deformation field.<br><br>my 2 cents...<br>Ganesh<br><br><font style="" color="#1f497d" face="Verdana">************************************************************************</font><font style="" color="#1f497d" face="Verdana"><br></font><font style="" color="#1f497d" face="Verdana">
"What the mind of man can conceive and believe, It can achieve" - </font><font style="" color="#1f497d" face="Verdana"><span class="ecxil">Napolean</span></font><font style="" color="#1f497d" face="Verdana"> </font><font style="" color="#1f497d" face="Verdana"><span class="ecxil">Hill</span></font><font style="" color="#1f497d" face="Verdana"><br></font><font style="" color="#1f497d" face="Verdana">
-Ganesh
Narayanasamy,Ph.D., PostDoc-University of Kentucky Cancer Center</font><font style="" color="#1f497d" face="Verdana"><br></font><font style="" color="#1f497d" face="Verdana">
Earlier work:
http://www.sciencedaily.com/releases/2007/05/070504133017.htm</font><font style="" color="#1f497d" face="Verdana"><br></font><font style="" color="#1f497d" face="Verdana">
************************************************************************</font><br><br>> Date: Thu, 6 May 2010 09:19:48 +1000<br>> From: Xi Liang <liangxi1986317@hotmail.com><br>> Subject: Re: [Insight-users] modify deformation field<br>> <br>> Thank you for your suggestion, but I think I did not make myself clear in<br>> the last question. I was trying to modify the deformation field itself (not<br>> moving image) to enforce a certain set of the deformation field is equal to<br>> a rigid transformation. The set of deformation field need to modify is find<br>> from a mask in the moving image.<br>> <br>> The motivation is, the original deformation field is a nonrigid deformation,<br>> however, I would like to apply it on a image that only certain part of the<br>> image is nonrigid. Thus I will have to modify the deformation field to allow<br>> only rigid deformation applied on the rigid structure of the image,<br>> and nonrigid deformation on the nonrigid structures. I hope this make sense.<br>> <br>> That was the question I want to ask. However, later I realized that<br>> modifying the deformation field might not be the right way to enforce the<br>> rigid deformation. Instead, the better way is to modify the control point<br>> parameters (Bspline transformation) to enforce the rigid transformation,<br>> based on Tanner's paper in 2000. I post a question on this in another post.<br>> <br><br> <br /><hr />The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with Hotmail. <a href='http://www.windowslive.com/campaign/thenewbusy?tile=multicalendar&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5' target='_new'>Get busy.</a></body>
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