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<p class="MsoNormal">Dear ITK community,<o:p></o:p></p>
<p class="MsoNormal">I’m doing some segmentation tests over a set of CT DICOM images, but I’ve some difficulties with the configuration of the thresholds. If I convert the images to .png format, I don’t have this problem, because the threshold definition is
quite straightforward when the images are in the range 0-255.<o:p></o:p></p>
<p class="MsoNormal">If I analyse one of the Dicom images with Matlab or using the StatisticsImageFilter I see that it has values between 0 and 946. Then, if I call the ConnectedThresholdImageFilter example using as lowerThreshold 0 and upperThreshold 946 (just
to check the validity of these ranges), I don’t obtain a totally white image as expected. Doing some tests, I’ve discovered that in order to obtain the white image, the range has to be [-4,897], and I don’t understand why. I’ve also observed that the ranges
are different in each Dicom image and especially when they belong to different CT phases.<o:p></o:p></p>
<p class="MsoNormal">(I send you an image attached so you can see what I mean).<o:p></o:p></p>
<p class="MsoNormal">Having said this, my question is:<o:p></o:p></p>
<p class="MsoNormal">Is it necessary to make any pre-processing of the DICOM images? Or … Does the ConnectedThresholdImageFilter treats these images in a special way?
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks a lot in advance for your support!!! (This problem is driving me crazy…)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<o:p></o:p></p>
<p class="MsoNormal">Cristina<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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