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<DIV><FONT face=Verdana><FONT size=2>Hi,All</FONT></FONT></DIV>
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<DIV><FONT face=Verdana><FONT size=2> I don' understand how "Gradient
Descent"Optimizer work in intensity-based registration. How to compute the
gradient? the transform parameters did not have direct connection with intensity
in the image. so we can't write a function (similarity measure) whose variable
are transform parameters . How can use this opimizer to find the right
direction?</FONT></FONT></DIV>
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<DIV><FONT face=Verdana><FONT size=2>thank you so much!</FONT></FONT></DIV>
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<DIV><FONT face=Verdana><FONT size=2>Vivian</FONT></DIV>
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<DIV><FONT color=#c0c0c0><FONT size=2>fyy5581</FONT></DIV>
<DIV><FONT size=2>2007-03-07</FONT></FONT></DIV></FONT></BODY></HTML>