[Insight-users] Optimizer spikes

[Steven Boyd]

Hello,

When observing the progress of rigid registration using the 
QuaternionRigidTransformGradientDescentOptimizer via the metric value 
(i.e., MattesMutualInformation) spikes occur, and sometimes last for 2-3 
iterations.

Can somebody explain why there are spikes in the metric?  I would it's 
related to a change in step size of the optimizer, but I'm not sure why 
this would result in the spikes.

Regards,

Steve


-- 
Steven Boyd

PhD, PEng, Assistant Professor
Scholar, Alberta Heritage Foundation for Medical Research
Department of Mechanical and Manufacturing Engineering
Faculty of Kinesiology (Joint)
University of Calgary
2500 University Drive, N.W.
Calgary, Alberta, Canada, T2N 1N4

tel. 1.403.220.4173  fax. 1.403.282.8406  skboyd at ucalgary.ca
web. http://www.enme.ucalgary.ca/~skboyd
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