{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:48:06Z","timestamp":1760150886110,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T00:00:00Z","timestamp":1643673600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Shape-from-Shading represents the problem of computing the three-dimensional shape of a surface given a single gray-value image of it as input. In a recent paper, we showed that the introduction of an attenuation factor in the brightness equations related to various perspective Shape-from-Shading models allows us to ensure the well-posedness of the corresponding differential problems. Here, we propose a unified convergence result of a numerical scheme for several non-Lambertian reflectance models. This result is interesting since it can be easily extended to other non-Lambertian models in a unified and, therefore, powerful framework.<\/jats:p>","DOI":"10.3390\/jimaging8020036","type":"journal-article","created":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T09:59:21Z","timestamp":1643709561000},"page":"36","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Perspective Shape-from-Shading Problem: A Unified Convergence Result for Several Non-Lambertian Models"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4336-7262","authenticated-orcid":false,"given":"Silvia","family":"Tozza","sequence":"first","affiliation":[{"name":"Department of Mathematics, Alma Mater Studiorum\u2014Universit\u00e0 di Bologna, Piazza di Porta San Donato 5, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,1]]},"reference":[{"key":"ref_1","first-page":"283","article-title":"A Photometric Investigation of the Slopes and Heights of the Ranges of Hills in the Maria of the Moon","volume":"11","author":"Diggelen","year":"1951","journal-title":"Bull. 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