Hi Jsl,<br><br>I'm not sure exactly what you are talking about, but if all you are doing is transformations, then what I would do is *when* you are querying the tree, transform the query location into the coordinate system of the tree.<br>
<br>eg, you build the tree with the plain image ABC, let the tree coordinate system be X,Y<br><br>then you want to find a point close to x,y then you search for X,Y=x,y<br><br>if you then transform image ABC by adding 10 to y... so therefore X=x Y=y-10<br>
where X,Y are the tree coordinates, and x,y are the transformed coordinates.<br><br>Then if you want to find a point (21,56), then you transform into tree coords : (21,46) and then search.<br>remember, X=x, Y=y-10 so X=21, Y=56-10<br>
<br>any rotation, translation etc can reversed. matrix multiplications make this simple and quick to do.<br><br>that way you can avoid rebuilding the tree with each iteration, which would be expensive.<br><br>cheers<br>
Paul<br>
<br><div class="gmail_quote">2009/11/17 jsl n <span dir="ltr"><<a href="http://jsantam.hm">jsantam.hm</a>@<a href="http://hotmail.com">hotmail.com</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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Hi,<br><br> I'm using kdtree for searching for the closest point between two images.<br>The kdtree stores the points of one (fixed) of the two images and the second <br>one is iteratively transformed (rotated, translated, etc). The closest point is<br>
computed for each moved point each iteration. <br><br>This is the procedure, but, what happen if the fixed image (the one that the <br>kdtree stores) is also transformed each iteration? should I build a new kdtree <br>each iteration? I need to know if there is an efficient solution for this dynamic <br>
situations where all the image points (of the fixed image) are transformed in <br>the same way.<br><br>Thanks in advance.<br> <br><hr>49 habitantes, 49 expertos en Windows 7. Así es Sietes, <a href="http://www.sietesunpueblodeexpertos.com/" target="_blank"> ˇVisítalo!</a></div>
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