# Is possible to create segments by color pallete?

**URL:** <https://discourse.slicer.org/t/is-possible-to-create-segments-by-color-pallete/43094>\
**Category:** Support\
**Tags:** segmentation\
**Created:** [May 25, 2025, 7:36pm UTC](https://discourse.slicer.org/t/is-possible-to-create-segments-by-color-pallete/43094 "2025-05-25T19:36:17Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![GioM](https://avatars.discourse-cdn.com/v4/letter/g/e56c9b/32.png) [@GioM](https://discourse.slicer.org/u/GioM)\
**Post date:** [May 25, 2025, 7:36pm UTC](https://discourse.slicer.org/t/is-possible-to-create-segments-by-color-pallete/43094/1 "2025-05-25T19:36:17Z")

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Hi all, is it possible to select all the voxels of an image by specifying a color?  
I have some CT maps of the brain that highlight the areas with different colors, the simplest one has only one color per map.  
This is an example.

 ![Immagine 2025-05-25 104706](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/9/7/97ab85ab8d6fd419a53ca274264c983b84a9b512.png)  
Is there any integrated Slicer tool or exention (or maybe a Python script) to do so?  
Thanks in advice.

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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:** [May 25, 2025, 7:44pm UTC](https://discourse.slicer.org/t/is-possible-to-create-segments-by-color-pallete/43094/2 "2025-05-25T19:44:42Z")

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All segment editor effects currently use a single channel. If you want to select a region based on exact RGB match then you can use a simple Python command as shown in this [example in the script repository](https://slicer.readthedocs.io/en/latest/developer_guide/script_repository.html#read-and-write-a-segment-as-a-numpy-array).