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Hello,<br>
Usually, scanners do this for you and you don't have to do it
manually, we only use constants for i0 (--i0) and dark (--idark). If
you have to do it, you can use itk to do it projection per
projection. The filters you use are <br>
itk::SubractImageFilter (difference between two images)<br>
itk::DivideImageFilter (ratio between two images)<br>
itk::LogImageFilter<br>
I've done this for some cases, e.g.,
XRadRawToAttenuationImageFilter, look at the code.<br>
Simon<br>
<br>
<div class="moz-cite-prefix">On 22/04/2016 13:27, AMJAD N wrote:<br>
</div>
<blockquote
cite="mid:CAHq1iunhBem1M6NsDKnDHyOVEBBNdMPUaHBaLhYpqkZ2iimGuQ@mail.gmail.com"
type="cite">
<div dir="ltr">Hello users,
<div><br>
</div>
<div>I have read Flat field image correction using dark (
projection with CT-off, detector-on ) and bright ( projection
with CT-on, detector-on and no object in between CT and
detector ) images procured before scanning any substance.</div>
<div><br>
</div>
<div>correction = log (bright image) - log ( projection-dark
image ); // for all projections</div>
<div><br>
</div>
<div>This pre-processed images are then fed to FDK algorithm.</div>
<div><br>
</div>
<div>Did someone here tried this method? If I want to implement
this, do I have to write a separate class for this? Any
suggestions for that? </div>
<div><br>
</div>
<div>PS: Presently I am
using LUTbasedVariableI0RawToAttenuationImageFilter and I am
getting reasonably good output. When i implemented FDK in
MATLAB i used this flat field correction and result was good.
So I want to know the impact with RTK.</div>
<div><br>
</div>
<div>Thanks and Regards,</div>
<div><br>
</div>
<div>AMJAD N</div>
</div>
<br>
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