<HTML dir=ltr><HEAD><TITLE>Re: [Insight-users] Rigid3DPerspectiveTransform</TITLE>
<META http-equiv=Content-Type content="text/html; charset=unicode">
<META content="MSHTML 6.00.6000.16608" name=GENERATOR></HEAD>
<BODY>
<DIV id=idOWAReplyText10746 dir=ltr>
<DIV dir=ltr><FONT face=Arial color=#000000 size=3><SPAN lang=EN-GB style="COLOR: black; FONT-FAMILY: Arial; mso-ansi-language: EN-GB">
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="COLOR: black; FONT-FAMILY: Arial; mso-ansi-language: EN-GB">D</SPAN><SPAN lang=EN-GB style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Arial; mso-ansi-language: EN-GB">ear Bill</SPAN><SPAN lang=EN-GB style="FONT-SIZE: 10pt; mso-ansi-language: EN-GB"><?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; mso-ansi-language: EN-GB"><FONT face="Times New Roman"> <o:p></o:p></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; mso-ansi-language: EN-GB">Yes I already used the Insight/Examples/DigitallyReconstructedRadiograph1.cxx example. Unfortunately I have problems defining the proper transformation. Instead of transforming the object (e.g. bone volume) the virtual C-arm is rotated as well as translated around the image volume. When I define only a rotation or a translation every thing works fine. However when I apply both rotation as well as translation the result is not what I expected. </SPAN><SPAN lang=EN-GB style="FONT-SIZE: 10pt; mso-ansi-language: EN-GB"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; mso-ansi-language: EN-GB"><FONT face="Times New Roman"> <o:p></o:p></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; mso-ansi-language: EN-GB">Using a parallel projection for the generation of DRR would be of less value for me as I would like to match those DRRs to a real fluoroscopic image. In fact I must admit that I miss a function like itkRayCaster-SetViewAngle(). As the itk::ResampleImageFilter defining the dimensions as well as the image resolution of the DRR is generated after the itk::RayCaster has done its work suggests, that the projection angle at which the RayCaster calculates the DRR is fixed.<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; mso-ansi-language: EN-GB"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; mso-ansi-language: EN-GB">However if anyone could explain me the proper usage of DigitallyReconstructedRadiograph1.cxx, maybe that will solve my problem. Anyway I thought using itk::Rigid3DPerspectiveTransform would be more efficient as it has been especially designed to generate DRRs ;-)<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; mso-ansi-language: EN-GB"><o:p> </o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; mso-ansi-language: EN-GB"><o:p><FONT face="Times New Roman"> </FONT></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; mso-ansi-language: EN-GB"><FONT face="Times New Roman"> <o:p></o:p></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; mso-ansi-language: EN-GB">Regards, Peter.</SPAN><SPAN lang=EN-GB style="FONT-SIZE: 10pt; mso-ansi-language: EN-GB"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"></SPAN></P></FONT></DIV>
<DIV dir=ltr><FONT face=Arial color=#000000 size=3></FONT> </DIV></DIV>
<DIV id=idSignature53622 dir=ltr>
<DIV><FONT face=Arial></FONT> </DIV></DIV>
<DIV dir=ltr><BR>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>Von:</B> Bill Lorensen [mailto:bill.lorensen@gmail.com]<BR><B>Gesendet:</B> Mo 21.04.2008 18:42<BR><B>An:</B> Boettcher, Dr. Peter<BR><B>Cc:</B> insight-users @ itk. org<BR><B>Betreff:</B> Re: [Insight-users] Rigid3DPerspectiveTransform<BR></FONT><BR></DIV>
<DIV>
<P><FONT size=2>Peter,<BR><BR>I the past at GE, we generated DRR's using the ExpNegativeImageFilter<BR>and AccummulateImageFilter. These resulted in parallel projections<BR>along each of the major planes, not Perspective projections. I do<BR>recall that we also successfully generated arbitrary DRR's with<BR>Insight/Examples/DigitallyReconstructedRadiograph1.cxx. I have no<BR>experience with similar code in InsightApplications. Which code were<BR>you using in InsightApplications?<BR><BR>Bill<BR><BR>On Mon, Apr 21, 2008 at 11:13 AM, Boettcher, Dr. Peter<BR><Boettcher@kleintierklinik.uni-leipzig.de> wrote:<BR>><BR>> I try to use Rigid3DPerspectiveTransform for the generation of digitally<BR>> reconstructed radiographs (DRR). The example within the ITKApplication uses<BR>> the RayCaster instead of Rigid3DPerspectiveTransform. Searching the mailing<BR>> list as well as the web I did not find any example on how to use that<BR>> filter. The testing script does only transform points and not an image<BR>> volume.<BR>> I suppose I will have to declare Rigid3DPerspectiveTransform as my<BR>> transformer. In additon to that I will need an image resample filter and an<BR>> interpolator. However pluggin those components together does not work.<BR>><BR>> ImageResampleFilter->SetTransform(Rigid3DPerspectiveTransform) does ot<BR>> compile.<BR>><BR>> Regards, Peter.<BR>><BR>><BR>> _______________________________________________<BR>> Insight-users mailing list<BR>> Insight-users@itk.org<BR>> <A href="http://www.itk.org/mailman/listinfo/insight-users">http://www.itk.org/mailman/listinfo/insight-users</A><BR>><BR>><BR></FONT></P></DIV></BODY></HTML>