{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T02:44:14Z","timestamp":1770432254901,"version":"3.49.0"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":20,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>This study introduces a physics-based and computer vision methodology for estimating ocean wave heights from oblique imagery using wave shadow observations. The approach combines image segmentation for shadow detection with projective geometry from the visible horizon for spatial scaling and solar geometry corrections to relate shadow length to wave height. Unlike data-driven approaches, the method relies solely on first-principles optics and geometry, requiring no training data or empirical calibration. Validation against in situ pressure sensor measurements demonstrates strong performance within platform-specific operational constraints. High-altitude UAV deployments (48.9-140 m) achieved MAPE = 6.7%, RMSE = 0.21 m (R\u00b2 = 0.80) at solar elevations exceeding 20\u00b0, providing nearly continuous daylight coverage. Low-altitude fixed camera deployment (35 m) achieved MAPE = 9.8%, RMSE = 0.19 m (R\u00b2 = 0.33) but requires solar elevation exceeding 35\u00b0 (oblique viewing causes shadows to project beyond field of view at lower angles) and morning deployment (tidal rise &gt; 1.5 m after midday reduces effective camera height, introducing systematic errors up to 79%). Both platforms achieve state-of-art accuracy within operational envelopes, offering practical coastal wave monitoring using readily available cameras.<\/jats:p>","DOI":"10.2139\/ssrn.6181640","type":"posted-content","created":{"date-parts":[[2026,2,5]],"date-time":"2026-02-05T12:37:32Z","timestamp":1770295052000},"source":"Crossref","is-referenced-by-count":0,"title":["Shadow-Based Automated Estimation of Non-Breaking Wave Heights with Adaptive Solar Corrections"],"prefix":"10.2139","author":[{"given":"Tochukwu","family":"Ngene","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3438-3479","authenticated-orcid":true,"given":"Tiago","family":"Abreu","sequence":"additional","affiliation":[]},{"given":"P.  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