Papers & code

SD-Retinex: A Stable Retinex Method for Low-Light Image Enhancement Designed Around the Sigmoid Derivative(opens in a new tab)

Toma Okugawa — Zenodo

A training-free, CPU-only low-light enhancement method built on the sigmoid derivative, with a pole-free real-axis kernel and a bounded tone map. Best PSNR and lowest color error among the training-free methods tested on LOL eval15.

• DOI: 10.5281/zenodo.20945211(opens in a new tab)
• Code(opens in a new tab)

複素指数カーネルに基づく高速・構造保持型 Retinex手法 XCRの提案(opens in a new tab)

A High-Speed and Structure-Preserving Retinex Method Based on a Complex Exponential Kernel: XCR

Toma Okugawa — Jxiv

A Retinex method that estimates illumination with a separable kernel derived analytically from the complex exponential. Processes 1080p video at an average of 15.32 FPS on a CPU alone (measured on a Snapdragon X PC).

• DOI: 10.51094/jxiv.1961(opens in a new tab)

Fast Single-Scale Retinexの提案と低照度環境におけるリアルタイム骨格検出性能の評価(opens in a new tab)

Proposal of Fast Single-Scale Retinex and Evaluation of Real-Time Skeleton Detection Performance in Low-Light Environments

Toma Okugawa — Jxiv

Proposes a fast Single-Scale Retinex and evaluates real-time skeleton detection in low-light environments.

• DOI: 10.51094/jxiv.1897(opens in a new tab)

Re-Defining Vanishing Municipalities in Japan: A Multidimensional Clustering and SLM-Based Policy Insight Framework

Toma Okugawa, Keito Inoshita — IEEE 15th Global Conference on Consumer Electronics (GCCE 2026)

A framework that combines multidimensional clustering with small language models (SLMs) to redefine “vanishing municipalities” in Japan and derive policy insights.

リアルタイム姿勢推定による弓道フォーム評価手法の提案とWeb実装

Proposal and Web Implementation of a Kyudo Form Evaluation Method Based on Real-Time Pose Estimation

Toma Okugawa, Tomonari Masuzaki, Takahiro Makiyama — Shikoku-Section Joint Convention of the Institutes of Electrical and Related Engineers

Proposes a method for evaluating kyudo (Japanese archery) form using real-time pose estimation, implemented as a web application. Received the Outstanding Presentation Award.