[Insight-users] Whats most expensive; the optimizer or the metric?

[Luis Ibanez]

Hi Motes,

Your assumption is correct.

The Metric is the class that consumes most of
the computation time during a registration process.

In particular, the methods:

   GetValue()
   GetValueAndDerivative()

are the ones that will take the bulk of the computation time.


The Optimizer intervenes at short times, just to figure out
what set of parameters to use next when calling the GetValue()
or GetValueAndDerivative() methods of the Metric.


     Regards,


            Luis


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On Wed, Nov 11, 2009 at 5:27 PM, motes motes <mort.motes at gmail.com> wrote:
> I am trying to understand which of the components in the image
> registration method is the most expensive. Now the optimizer is run
> for each iteration where it starts the optimizer which runs through
> all the pixels in the fixed image. Even though the optimizer hardly
> makes any sense without a metric I would still say that the most
> expensive operation is the computation done by the metric or am I
> missing something here?
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