<html><head><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">I agree this is a documentation error. Wikipedia seems to agree with the source code:<div><br></div><div><a href="http://en.wikipedia.org/wiki/Shape_factor_(image_analysis_and_microscopy)#Elongation_shape_factor">http://en.wikipedia.org/wiki/Shape_factor_(image_analysis_and_microscopy)#Elongation_shape_factor</a></div><div><br><div><div>On Aug 22, 2013, at 5:13 PM, Cagatay Bilgin <<a href="mailto:bilgincc@gmail.com">bilgincc@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><div dir="ltr"><div>Hello everyone, </div><div><br></div><div>Either I am missing something or the write up about the elongation is not matching the actual implementation. </div><div><br></div><div>"elongation is computed as the ratio of the largest principal moment by the smallest principal moment. "</div>
<div><br></div><div>however in itkShapeLabelMapFilter.hxx elongation is defined as largest principal moment / second largest principal moment. In 3D the definition and the implementation becomes inconsistent. </div><div><br>
</div><div>from itkShapeLabelMapFilter.hxx </div><div>331 elongation = vcl_sqrt(principalMoments[ImageDimension - 1] / principalMoments[ImageDimension - 2]);</div><div>332 flatness = vcl_sqrt(principalMoments[1] / principalMoments[0]);</div>
<div> </div><div>Cheers, </div><div>C. Cagatay Bilgin </div><div><br></div>-- <br><span style="color:rgb(136,136,136);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">Cemal Cagatay Bilgin</span>, <span style="color:rgb(136,136,136);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">PhD</span><br style="color:rgb(136,136,136);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">
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<span style="color:rgb(136,136,136);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">Email: <a href="mailto:ccbilgin@lbl.gov" target="_blank">ccbilgin@lbl.gov</a></span>
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