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<p>Hi all,<br>
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<p>It seems to be a bug for itk.OtsuThresholdImageFilter. When I use SetInsideValue(0) and SetOutsideValue(255), I got the result displayed in Fig. 2, where inside voxel value is 255 and outside voxel value is 0. Inversely, when I use SetInsideValue(255) and
SetOutsideValue(0), I got the result displayed in Fig. 3, where the inside voxel value is 0 and the outside voxel value is 255. It seems totally inversely. Is that right? Have someone else met this situation before? Thanks in advance.<br>
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<p>Regards,<br>
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<p>Zhuangming Shen<br>
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<p>=============== My code =================<br>
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<p>import itk<br>
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<p>reader = itk.ImageFileReader[itk.Image.SS3].New()<br>
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<p>reader.SetFileName("ct.nrrd")<br>
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<p>reader.Update()<br>
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<p>otsu_filter = itk.OtsuThresholdImageFilter​[itk.Image.SS3, itk.Image.UC3].New()<br>
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<p>otsu_filter.SetInput(reader.GetOutput())<br>
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<p>otsu_filter.SetInsideValue(0)<br>
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<p>otsu_filter.SetOutsideValue(255)<br>
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<p>otsu_filter.Update()<br>
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<p>writer = itk.ImageFileWriter[itk.Image.UC3].New()<br>
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<p>writer.SetInput(otsu_filter.GetOutput())<br>
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<p>writer.SetFileName("otsu.nrrd")<br>
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<p>writer.Update()<br>
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<p>Fig. 1 ct.nrrd<br>
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<p><img name="null" title="pastedImage.png" originalwidth="511" originalheight="509" rszimgcmd="100" src="cid:15b5cb2e-24ee-4092-99ff-d5bfd99c9d58"><br>
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<p>Fig. 2 otsu segmentation result for SetInsideValue(0) and SetOutsideValue(255)<br>
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<p><img name="null" title="pastedImage.png" originalwidth="513" originalheight="510" rszimgcmd="100" src="cid:1c274aac-d532-4e55-8d5e-0a5847dea5af"><br>
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<p>Fig. 3 <span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);">otsu segmentation result for SetInsideValue(255) and SetOutsideValue(0)</span><br>
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<p><img name="null" title="pastedImage.png" originalwidth="504" originalheight="503" rszimgcmd="100" src="cid:917c3ca4-8e81-4d99-af7c-fc6af0639a43"><br>
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