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<DIV><FONT face=Verdana size=3>Hi All,</FONT></DIV>
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<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US
style="FONT-SIZE: 12pt"><FONT face="Times New Roman">In the example
DeformableRegistration4.cxx, the itkMeanSquaresImageToImageMetric is used as the
metric method, and the optimization method is LBFGS, and in the LBFGS the
derivations have to be calculated to obtain the Hessian matrix. Generally the
derivation is easy to calculate, such as f(x)= x^2 , f¡¯(x)=2x, but how to
calculate the derivatons of images? because I don¡¯t know the
expression of the function, and how we explain the derivations of images? would
anyone please explain this? Thanks every much!</FONT></SPAN></P>
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style="FONT-SIZE: 12pt"><FONT face="Times New Roman"> </P>
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<DIV align=left><FONT face=Verdana color=#c0c0c0 size=2>2009-03-05
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<DIV><FONT face=Verdana color=#c0c0c0 size=2><SPAN>shengzhouxu</SPAN>
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