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<FONT color=#000000>Hello ITK,</FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>I´m working with ITK to do registration of 2D images and I think I reach a local minima that makes a poor registration.</FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>I´m using 2D images 2000x2000 pixels in what the moving image needs a rotation and a translation. So I reproduced the ImageRegistration6.cxx to do that. But the result I got is not good enough so I think that the MeanSquares metric reaches a local minima. The value of the metric is about 4000 (aprox.), and I run a test using as input parameters the optimal ones (that is, the result I think i should obtain) and the metric returns a value of 2500 (aprox.). </FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>The framework I use is:</FONT><BR>
<FONT color=#000000> </FONT><BR>
<FONT color=#000000> itkImageRegistrationMethod</FONT><BR>
<FONT color=#000000> itkMeanSquaresImageToImageMetric</FONT><BR>
<FONT color=#000000> itkLinearInterpolateImageFunction</FONT><BR>
<FONT color=#000000> itkRegularStepGradientDescentOptimizer</FONT><BR>
<FONT color=#000000> itkCenteredRigid2DTransform</FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>And the parameters of my registration are:</FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>const double translationScale = 1.0 / 1000.0;</FONT><BR>
<FONT color=#000000>optimizerScales[0] = 1.0;</FONT><BR>
<FONT color=#000000>optimizerScales[1] = translationScale;</FONT><BR>
<FONT color=#000000>optimizerScales[2] = translationScale;</FONT><BR>
<FONT color=#000000>optimizerScales[3] = translationScale;</FONT><BR>
<FONT color=#000000>optimizerScales[4] = translationScale;</FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>optimizer->SetMaximumStepLength( 0.1 );</FONT><BR>
<FONT color=#000000>optimizer->SetMinimumStepLength( 0.001 );</FONT><BR>
<FONT color=#000000>optimizer->SetNumberOfIterations( 200 );</FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>The scales are well defined and I tried to vary the parameters of the optimizer but the results were similar, so I don´t know what to do next. Any idea??</FONT><BR>
<FONT color=#000000></FONT> <BR>
<FONT color=#000000>Thank you in advance, I hope you can have more ideas to try.</FONT><BR>
<BR>
<BR>
<BR>
<FONT color=#000000>Manuel.</FONT><BR>
<FONT color=#800000></FONT> <BR>
<FONT color=#800000></FONT> <BR>
<FONT color=#800000></FONT> <BR>
<FONT color=#800000></FONT><FONT color=#800000 size=2><FONT color=#800000 size=2><FONT size=2><FONT size=2></FONT></FONT></FONT></FONT> <BR> <br /><hr />Todo el espacio y cuidado que merecen tus fotos digitales lo tienes en Windows Live Fotos. <a href='http://www.vivelive.com/compartirfotos/' target='_new'>¡Pruébalo! </a></body>
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