{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T21:03:54Z","timestamp":1768511034684,"version":"3.49.0"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T00:00:00Z","timestamp":1768262400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["61771432"],"award-info":[{"award-number":["61771432"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["61302118"],"award-info":[{"award-number":["61302118"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Key projects Natural Science Foundation of Henan","award":["232300421150"],"award-info":[{"award-number":["232300421150"]}]},{"name":"Zhongyuan Science and Technology Innovation Leadership Program","award":["244200510026"],"award-info":[{"award-number":["244200510026"]}]},{"name":"Scientific and Technological Project of Henan Province","award":["232102211014"],"award-info":[{"award-number":["232102211014"]}]},{"name":"Scientific and Technological Project of Henan Province","award":["23210221101"],"award-info":[{"award-number":["23210221101"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Efficient intra-mode decision for depth maps assumes a pivotal role in augmenting the overall performance of 3D-HEVC. Existing research endeavors predominantly rely on fast mode screening strategies grounded in texture characteristics or machine learning techniques. These strategies, to a certain extent, mitigate the complexity of mode search. Nevertheless, these approaches often fall short of fully leveraging the intrinsic spatio-temporal correlations within depth maps. Moreover, strategies relying on deterministic classifiers exhibit insufficient discrimination reliability in regions featuring edge mutations or intricate structures. To tackle these challenges, this paper presents a two-stage fast intra-mode decision algorithm for depth maps, integrating naive Bayes probability estimation and fuzzy support vector machine (FSVM). Initially, it confines the candidate mode space through spatio-temporal prior modeling. Subsequently, FSVM is employed to enhance the decision accuracy in regions with low confidence. This methodology constructs a joint mode decision framework spanning from probability screening to refined classification. By doing so, it significantly reduces the computational burden while preserving rate-distortion performance, thereby attaining an effective equilibrium between encoding complexity and performance. Experimental findings demonstrate that the proposed algorithm reduces the average encoding time by 52.30% with merely a 0.68% increment in BDBR. Additionally, it showcases stable universality across test sequences of diverse resolutions and scenes.<\/jats:p>","DOI":"10.3390\/s26020529","type":"journal-article","created":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T15:52:57Z","timestamp":1768319577000},"page":"529","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Fast 3D-HEVC Depth Map Coding Method Based on Spatio-Temporal Correlation and a Two-Stage Mode Decision Framework"],"prefix":"10.3390","volume":"26","author":[{"given":"Erlin","family":"Tian","sequence":"first","affiliation":[{"name":"College of Computer Science and Technology, Zhengzhou University of Light Industry, Zhengzhou 450002, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiabao","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Computer Science and Technology, Zhengzhou University of Light Industry, Zhengzhou 450002, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiuwen","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Computer Science and Technology, Zhengzhou University of Light Industry, Zhengzhou 450002, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6987","DOI":"10.1007\/s11042-019-08461-9","article-title":"Fast CU size and mode decision algorithm for 3D-HEVC intercoding","volume":"79","author":"Bakkouri","year":"2020","journal-title":"Multimed. 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