<br>Hi Motes,<br><br><br>The fact that this optimizer is applied to registration<br>of digital images is irrelevant.<br><br><br>All ITK optimizers are general purpose optimizers.<br><br><br>These Optimizers explore a parametric space looking <br>
for good values of a cost function.<br><br>When applied to image registration the Cost function<br>happens to be an ImageMetric, and the parametric<br>space happens to be the set of parameters of a <br>Transform.<br><br><br>
The Image Registration chapter of the ITK Software Guide<br><a href="http://www.itk.org/ItkSoftwareGuide.pdf">http://www.itk.org/ItkSoftwareGuide.pdf</a> shows many plots<br>of the Metric with respect to the optimizer iterations, as <br>
well as many plots of the Transform parameters for multiple<br>iterations of the optimizer.<br><br>Have you seen these figures ?<br><br><br><br>Could you please clarify what kind of step-by-step<br>
example are you looking for ?<br>
<br>
<br><br>Simply "applying an optimizer to a digital image" <br>doesn't quite makes sense...<br><br><br><br>Are you looking for image enhancement filters ?<br>maybe ?<br><br><br> Please elaborate on the context of your question,<br>
<br><br> Thanks<br><br><br> Luis<br><br><br><br>----------------------------------------------------------------<br><div class="gmail_quote">On Tue, Jun 30, 2009 at 4:13 PM, motes motes <span dir="ltr"><<a href="mailto:mort.motes@gmail.com">mort.motes@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">A lot of the examples in the itkSoftwareGuide uses the optimizer defined in itkRegularStepGradientDescentOptimizer.h.<br>
<br>As I understand this i a gradient descent optimzer. There is not much details about this method in the guide (I assume its rather basic) but it could be very nice to read some examples showing how this optimizer works for a few iterations.<br>
<br>I have tried googling articles and websites that show how gradient descent is applied in the context of digital image processing but cannot seem to find anything. Does anyone on this mailing list know of any good resources to a step-by-step example using the gradient descent method on a digital image?<br>
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