Feature/elen thresholding

[abdullahelen]

Summary

This pull request adds a new global thresholding function, elen(), based on the method proposed by Elen & Dönmez (2024). It is implemented in thresholding.py and designed to align with Mahotas' thresholding interface.

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Changes Made

• ✅ Added elen() function to thresholding.py
• ✅ Included unit test in test_thresholding.py
• ✅ Updated __all__ list to expose the new method

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Method Description

The method works by:

• Computing the global mean and standard deviation of the image histogram
• Defining an α-region: [mean − std, mean + std]
• Computing average intensities of α and β (peripheral) regions
• Setting the threshold as the mean of the α and β regional averages

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Example Usage

import mahotas
t = mahotas.elen(image)
binary = (image > t)