# Does the parameter unit in IntensityWindowImageFilter represent the Hounsfield unit?

**URL:** <https://discourse.slicer.org/t/does-the-parameter-unit-in-intensitywindowimagefilter-represent-the-hounsfield-unit/35183>\
**Category:** Support\
**Tags:** dicom\
**Created:** [March 31, 2024, 4:41am UTC](https://discourse.slicer.org/t/does-the-parameter-unit-in-intensitywindowimagefilter-represent-the-hounsfield-unit/35183 "2024-03-31T04:41:52Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Nutchanon\_Hemapattam](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/nutchanon_hemapattam/32/68410_2.png) [@Nutchanon\_Hemapattam](https://discourse.slicer.org/u/Nutchanon_Hemapattam)\
**Post date:** [March 31, 2024, 4:41am UTC](https://discourse.slicer.org/t/does-the-parameter-unit-in-intensitywindowimagefilter-represent-the-hounsfield-unit/35183/1 "2024-03-31T04:41:52Z")

</div>

![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/0/e/0ec2a447fbaeab01b97d6dc822a081937f18a5c4.png)

---

<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [March 31, 2024, 7:25pm UTC](https://discourse.slicer.org/t/does-the-parameter-unit-in-intensitywindowimagefilter-represent-the-hounsfield-unit/35183/2 "2024-03-31T19:25:31Z")

</div>

If you load a clinical CT image from DICOM then usually the voxel values are in Hounsfield unit. Cone-beam CT, micro-CT, pre-clinical CT scans are often not in Hounsfield units.

If `Input volume` voxel values are in HU, then `Window Minimum` and `Window Maximum` are in HU.

---

<div class="post-metadata">

**Author:** ![Nutchanon\_Hemapattam](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/nutchanon_hemapattam/32/68410_2.png) [@Nutchanon\_Hemapattam](https://discourse.slicer.org/u/Nutchanon_Hemapattam)\
**Post date:** [April 1, 2024, 2:07am UTC](https://discourse.slicer.org/t/does-the-parameter-unit-in-intensitywindowimagefilter-represent-the-hounsfield-unit/35183/3 "2024-04-01T02:07:31Z")

</div>

Thank you very much for reply.