[Insight-users] Three registration questions

[Luis Ibanez]

Hi Greg,


1) You can stop the Optimizer by invoking


       optimizer->StopOptimization()

    Your Observer probably have already a
    pointer to the optimizer.



2) What ITK class are you refering to when
    you talk about the "Nelder-Mead" optimizer ?


3) Nope,
    Constrained optimization is not implemented in ITK.
    It has been suggested a couple of times though.
    If you will like to undertake an implementation
    we will be happy to assist you, and of course, we
    will encourage you to contribute your code to the
    toolkit.



Regards,


     Luis


---------------------
Gregory Sharp wrote:

> Hi, I'm new to itk, and I am trying to do some simple 
> 3D registration with translation only and MSE cost 
> function.
> 
> 1)  I started with RegularStepGradientDescentOptimizer,
> and I want to monitor with an observer.  The software
> guide says:
> 
>   "For example, you could imagine a 
>   non-const interaction in which the observer decides
>   to stop the optimizer in response to a divergent behavior.
> 
> OK, I'll bite.  How can I stop the registration from 
> the observer?  I'd want to do this from either the 
> optimizer observer or the registration observer.
> 
> 2)  I also tried the Nelder-Mead optimizer, and this one 
> doesn't seem to give any observer callbacks, and it doesn't
> seem to have a GetValue() method.  Is this right?
> 
> 3)  Can I do constrained optimization?  Any example code?
> 
> Thanks,
> Greg
> 
> 
> =====
> Greg Sharp
> gregsharp at geocities.com
> 
>