LOG-STAT: AN ILLUMINATION-BALANCING ALGORITHM FOR ARCHAEOLOGICAL IMAGES CAPTURED IN NON-IDEAL LIGHTING

(Received: 18-Oct.-2025, Revised: 6-Dec.-2025 , Accepted: 23-Dec.-2025)

Authors Zohair Al-Ameen, Basim Mahmood,

Keywords #Archeology #Image enhancement #Log-Stat #Illumination balancing #Non-ideal lighting

Abstract Archaeological images are occasionally captured in environments with non-ideal lighting. This results in imbalanced illumination and a loss of detail. These problems hinder precise operations, such as analysis, interpretation, representation, and 3D modeling. This study introduces a non-complex illumination balancing algorithm called Log-Stat, leveraging logarithmic approaches and statistical methods. It also includes two main phases, one for illumination balancing and the other for tonality adjustment. The first phase utilizes six mathematical equations, while the second phase utilizes four equations, processing the V channel of the image in the HSV color model. Various images have been used to test the algorithm, and a comparison with ten prominent algorithms is achieved, evaluating the outcomes using six measures. The results have shown the success of Log- Stat in different aspects, including fidelity recovery and illumination balance. This allowed better visualization of details, which the unbalanced illumination effect hindered. Integrating appropriate methods and fine-tuning the parameters enabled the Log-Stat to perform in dissimilar illumination situations.

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