{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T13:31:08Z","timestamp":1762263068413,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,1]],"date-time":"2025-11-01T00:00:00Z","timestamp":1761955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"crossref","award":["2022M3A9B6082791"],"award-info":[{"award-number":["2022M3A9B6082791"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Reliable acupoint localization is essential for developing artificial intelligence (AI) and extended reality (XR) tools in traditional Korean medicine; however, conventional annotation of 2D images often suffers from inter- and intra-annotator variability. This study presents a low-cost dual-camera imaging system that fuses infrared (IR) and RGB views on a Raspberry Pi 5 platform, incorporating an IR ink pen in conjunction with a 780 nm emitter array to standardize point visibility. Among the tested marking materials, the IR ink showed the highest contrast and visibility under IR illumination, making it the most suitable for acupoint detection. Five feature detectors (SIFT, ORB, KAZE, AKAZE, and BRISK) were evaluated with two matchers (FLANN and BF) to construct representative homography pipelines. Comparative evaluations across multiple camera-to-surface distances revealed that KAZE + FLANN achieved the lowest mean 2D error (1.17 \u00b1 0.70 px) and the lowest mean aspect-aware error (0.08 \u00b1 0.05%) while remaining computationally feasible on the Raspberry Pi 5. In hand-image experiments across multiple postures, the dual-camera registration maintained a mean 2D error below ~3 px and a mean aspect-aware error below ~0.25%, confirming stable and reproducible performance. The proposed framework provides a practical foundation for generating high-quality acupoint datasets, supporting future AI-based localization, XR integration, and automated acupuncture-education systems.<\/jats:p>","DOI":"10.3390\/jimaging11110388","type":"journal-article","created":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T16:18:42Z","timestamp":1762186722000},"page":"388","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluating Feature-Based Homography Pipelines for Dual-Camera Registration in Acupoint Annotation"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-5609-2992","authenticated-orcid":false,"given":"Thathsara","family":"Nanayakkara","sequence":"first","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea"}]},{"given":"Hadi Sedigh","family":"Malekroodi","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3720-7975","authenticated-orcid":false,"given":"Jaeuk","family":"Sul","sequence":"additional","affiliation":[{"name":"Gwangju Korean Medicine Hospital, Dongshin University, Gwangju 61619, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5478-649X","authenticated-orcid":false,"given":"Chang-Su","family":"Na","sequence":"additional","affiliation":[{"name":"Department of Diagnostics & Acupuncture, College of Korean Medicine, Dongshin University, Naju 58245, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4864-959X","authenticated-orcid":false,"given":"Myunggi","family":"Yi","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea"},{"name":"Major of Biomedical Engineering, Division of Smart Healthcare, Pukyong National University, Busan 48513, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1574-7145","authenticated-orcid":false,"given":"Byeong-il","family":"Lee","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Republic of Korea"},{"name":"Major of Human Bioconvergence, Division of Smart Healthcare, Pukyong National University, Busan 48513, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"145","DOI":"10.14406\/acu.2013.30.3.145","article-title":"A Short Reveiw on the Acupoints Used in Cocaine Studies","volume":"30","author":"Lee","year":"2013","journal-title":"Korean J. 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