<font color="#000000"><font><font face="arial,helvetica,sans-serif">Hello everybody,</font></font></font><div><font color="#000000"><font><font face="arial,helvetica,sans-serif"><br></font></font></font></div><div><font color="#000000"><font><font face="arial,helvetica,sans-serif">I have problems when perform Portal and DRR images registration (now I only test with 2D-Case). Portal image is very noisy, low contrast and have a wide range of intensity (from 0 to 60000), so that when I tried to run some algorithms of ITK, the results very very bad!</font></font></font></div>
<div><font color="#000000"><font><font face="arial,helvetica,sans-serif"><br></font></font></font></div><div><font color="#000000"><font><font face="arial,helvetica,sans-serif">I know that Portal and DRR are in different modality, so that if I use a intensity-based method of registration I should use Mutual Information metric, however the results not good.</font></font></font></div>
<div><font color="#000000"><font><font face="arial,helvetica,sans-serif"><br></font></font></font></div><div><font color="#000000"><font><font face="arial,helvetica,sans-serif">If I use a feature-based method, I must extract the features of images and matching them, the features can be here is: harris corner, SIFT, SUFT, MSER... However with Portal image it is very difficult to detect these keypoints.</font></font></font></div>
<div><font color="#000000"><font><font face="arial,helvetica,sans-serif"><br></font></font></font></div><div><font color="#000000"><font><font face="arial,helvetica,sans-serif">Now I am trying using ICP to match contour extracted from two images (using VTK), the results is better than other way but still isn't my expectation.</font></font></font></div>
<div><font color="#000000"><font><font face="arial,helvetica,sans-serif"><br></font></font></font></div><div><font color="#000000"><font><font face="arial,helvetica,sans-serif">I have read the file </font></font></font><font face="arial, helvetica, sans-serif"><a href="http://www.medphys.mcgill.ca/presentations/keyvan2004.pdf">http://www.medphys.mcgill.ca/presentations/keyvan2004.pdf</a> and I 'm going to use FFT-method to do this task.</font></div>
<div><font face="arial, helvetica, sans-serif"><br></font></div><div><font face="arial, helvetica, sans-serif">Could anyone give me some advises with my problem?</font></div><div><font face="arial, helvetica, sans-serif"><br>
</font></div><div><font face="arial, helvetica, sans-serif">Thanks in advance.</font></div><div><font face="arial, helvetica, sans-serif"><br></font></div><div><font face="arial, helvetica, sans-serif">/Quang</font></div>