# Rescaling the DICOM images using the RescaleIntercept and RescaleSlope

**URL:** <https://discourse.slicer.org/t/rescaling-the-dicom-images-using-the-rescaleintercept-and-rescaleslope/1733>\
**Category:** Support\
**Tags:** dicom\
**Created:** [December 27, 2017, 4:59pm UTC](https://discourse.slicer.org/t/rescaling-the-dicom-images-using-the-rescaleintercept-and-rescaleslope/1733 "2017-12-27T16:59:41Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![fukiracs](https://avatars.discourse-cdn.com/v4/letter/f/43a26b/32.png) [@fukiracs](https://discourse.slicer.org/u/fukiracs)\
**Post date:** [December 27, 2017, 4:59pm UTC](https://discourse.slicer.org/t/rescaling-the-dicom-images-using-the-rescaleintercept-and-rescaleslope/1733/1 "2017-12-27T16:59:41Z")

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Hello Everyone,

I am new to the 3D Slicer software and I wanted to know if there is an option to rescale the DICOM images (For example from a Cone Beam CT) using the RescaleSlope and RescaleIntercept. To convert from the normal units found in CT data (a typical data set ranges from 0 to 4000 or so) we have to apply a linear transformation of the data using an equation given as:

hu = pixel\_value \* slope + intercept

(Citation : [http://www.idlcoyote.com/fileio\_tips/hounsfield.html](http://www.idlcoyote.com/fileio_tips/hounsfield.html))

While I can apply this transformation in Matlab, but it requires a lot of time to rescale every \*.dcm file. Is there an option in 3D Slicer to do it? or is it automatically applied while loading the data into the software?. I will be grateful for the help.

Thank you.

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**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:** [December 27, 2017, 5:18pm UTC](https://discourse.slicer.org/t/rescaling-the-dicom-images-using-the-rescaleintercept-and-rescaleslope/1733/2 "2017-12-27T17:18:19Z")

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Rescaling is applied automatically. You can verify this by hovering the mouse pointer over the image and checking the voxel values displayed in the panel in the lower left corner.