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Hi all,<br>
<br>
I am using the itk::HoughTransform2DLinesImageFilter to extract the
lines from an image for a certain application. The point is that I
don't want to draw the lines but to get the lines parameters (direction
and a point ) for further computations. I realised that, following the
example from the software guide, the vector and the line are in pixel
coordinates and not in real world coordinates. Can anyone confirm this?<br>
<br>
So, what I did is to use the TransformIndexToPhysicalPoint() method,
but it does not work properly (mi lines are slightly deviated). My
assumption is that the extracted points are in pixel coordinates but
aren't integers. Because of that, the TransformIndexToPhysicalPoint()
method rounds them and then computes the physical coordinates, which
yields in the inaccuracy I realized. <br>
<br>
The solution I found was to get two points, in pixel coordinates, very
far from each other, so that the inaccuracy of the conversion is
smaller. Nevertheless, this is not clean. Does anyone know a way to get
the line parameters accurately in physical coordinates? I guess that
the Hough map (output of the filter) is (r, theta) in real physical
coordinates, but I don't know how to extract the maximums in the same
way that getLines() does (using the disc, etc).<br>
<br>
Thank you,<br>
Alberto<br>
<code><a class="el"
href="http://www.itk.org/Doxygen/html/itkHoughTransform2DLinesImageFilter_8h-source.html"></a></code>
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-- <br>
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<p>Alberto Gómez</p>
<p>
<i>Division of Imaging Sciences <br>
The Rayne Institute<br>
4th Floor, Lambeth Wing<br>
St Thomas' Hospital<br>
London SE1 7EH
</i></p>
<p>phone: +44 (0) 20 718 88364<br>
email: <a href="mailto:alberto.gomez@kcl.ac.uk">alberto.gomez@kcl.ac.uk</a>
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