# Semi automatic annotation of 2D image based on specific features

**URL:** <https://discourse.slicer.org/t/semi-automatic-annotation-of-2d-image-based-on-specific-features/37805>\
**Category:** Development\
**Tags:** segmentation, python, segmentations, segment-editor\
**Created:** [August 9, 2024, 9:11pm UTC](https://discourse.slicer.org/t/semi-automatic-annotation-of-2d-image-based-on-specific-features/37805 "2024-08-09T21:11:45Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![calrnence](https://avatars.discourse-cdn.com/v4/letter/c/c0e974/32.png) [@calrnence](https://discourse.slicer.org/u/calrnence)\
**Post date:** [August 9, 2024, 9:11pm UTC](https://discourse.slicer.org/t/semi-automatic-annotation-of-2d-image-based-on-specific-features/37805/1 "2024-08-09T21:11:45Z")

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Hello,

For this project I am working on, I am trying to use Python to draw a circle where the circle’s edge sits on an outline of a specific feature in a 2D image. I would like the program to be able to automatically identify the structure in the image and draw the circle.

Here is a manually drawn circle as an example of what I am trying to do:

![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/c/3/c36902255a732f3ef9e92a601a5c69fdb4b4d75e.png)

The reference image has been rescaled so the pixels are anisotropic.

I don’t really have experience with 3D Slicer and its libraries though I am experienced with Python so I would like some guidance on where to start.

Cheers,

calrnence