<p dir="ltr">I would try some much larger maximum step values. You program appears to be spending iterations while not making very much progress at the start.</p>
<p dir="ltr">Also, when you're tuning things, it can be helpful to print the moving image parameters on each iteration, in addition to the cost function.</p>
<div class="gmail_quote">On Nov 27, 2013 5:42 PM, "Hana Cherif" <<a href="mailto:hanacherif62@gmail.com">hanacherif62@gmail.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr"><div><div><br></div>Hello every body !<br><br><br></div><div>After execution of my images' registration program , using this components:<br><br></div><div>Regular Step Gradient Descent Optimizer,<br>Mean Squares Image  To Image Metric<br>

</div><div>Bspline interpolator<br><br> I get this results::<br><br><br>Iteration number:     Cost function value        <br><br><br>0                        2732.74                <br>1                        2700.84                <br>

2                        2699.27                <br>3                        2701.48                <br>4                        2703.19                <br>5                        2700                <br>6                        2704.12                <br>

7                        2705.1                <br>8                        2705.27                <br>9                        2705.4                <br>10                        2702.91                <br>11                        2705.15                <br>

12                        2713.1                <br>13                        2720.48                <br>14                        2720                <br>15                        2715.81                <br>16                        2704.64                <br>

17                        2687.46                <br>18                        2666.14                <br>19                        2639.91                <br>20                        2613.11                <br>21                        2587.55                <br>

22                        2564.89                <br>23                        2546.22   <br><br></div><div>I use this parameters:<br> optimizer->SetMaximumStepLength(0.10 );<br> optimizer->SetMinimumStepLength( 0.05);<br>

 optimizer->SetRelaxationFactor(0.5);<br><br></div><div>My question is : as you see i the results the value of the cost function increases i want to know why can be the reason of this results please!! is it just a probleme of parameters??<br>

<br></div><div>Thanks !<br></div><div><br></div><div><br></div></div>
<br>_____________________________________<br>
Powered by <a href="http://www.kitware.com" target="_blank">www.kitware.com</a><br>
<br>
Visit other Kitware open-source projects at<br>
<a href="http://www.kitware.com/opensource/opensource.html" target="_blank">http://www.kitware.com/opensource/opensource.html</a><br>
<br>
Kitware offers ITK Training Courses, for more information visit:<br>
<a href="http://www.kitware.com/products/protraining.php" target="_blank">http://www.kitware.com/products/protraining.php</a><br>
<br>
Please keep messages on-topic and check the ITK FAQ at:<br>
<a href="http://www.itk.org/Wiki/ITK_FAQ" target="_blank">http://www.itk.org/Wiki/ITK_FAQ</a><br>
<br>
Follow this link to subscribe/unsubscribe:<br>
<a href="http://www.itk.org/mailman/listinfo/insight-users" target="_blank">http://www.itk.org/mailman/listinfo/insight-users</a><br>
<br>_______________________________________________<br>
Community mailing list<br>
<a href="mailto:Community@itk.org">Community@itk.org</a><br>
<a href="http://public.kitware.com/cgi-bin/mailman/listinfo/community" target="_blank">http://public.kitware.com/cgi-bin/mailman/listinfo/community</a><br>
<br></blockquote></div>