{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T12:53:57Z","timestamp":1762260837802,"version":"build-2065373602"},"reference-count":65,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T00:00:00Z","timestamp":1762214400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Accurate object detection and measurement within indoor environments\u2014particularly unfurnished or minimalistic spaces\u2014pose unique challenges for conventional computer vision methods. Previous research has been limited to small objects that can be fully detected by applications such as YOLO, or to outdoor environments where reference elements are more abundant. However, in indoor scenarios with limited detectable references\u2014such as walls that exceed the camera\u2019s field of view\u2014current models exhibit difficulties in producing complete detections and accurate distance estimates. This paper introduces a geometry-driven, redundancy-based framework that leverages proportional laws and architectural heuristics to enhance the measurement accuracy of walls and spatial divisions using standard smartphone cameras. The model was trained on 204 labeled indoor images over 25 training iterations (500 epochs) with augmentation, achieving a mean average precision (mAP@50) of 0.995, precision of 0.995, and recall of 0.992, confirming convergence and generalisation. Applying the redundancy correction method reduced distance deviation errors to approximately 10%, corresponding to a mean absolute error below 2% in the use case. Unlike depth-sensing systems, the proposed solution requires no specialised hardware and operates fully on 2D visual input, allowing on-device and offline use. The framework provides a scalable, low-cost alternative for accurate spatial measurement and demonstrates the feasibility of camera-based geometry correction in real-world indoor settings. Future developments may integrate the proposed redundancy correction with emerging multimodal models such as SpatialLM to extend precision toward full-room spatial reasoning in applications including construction, real estate evaluation, energy auditing, and seismic assessment.<\/jats:p>","DOI":"10.3390\/s25216744","type":"journal-article","created":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T12:13:08Z","timestamp":1762258388000},"page":"6744","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Indoor Object Measurement Through a Redundancy and Comparison Method"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-4688-0829","authenticated-orcid":false,"given":"Pedro","family":"Faria","sequence":"first","affiliation":[{"name":"Infrastructure Department, Hainan University, Haikou 570228, China"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-8824-1613","authenticated-orcid":false,"given":"Tom\u00e1s","family":"Sim\u00f5es","sequence":"additional","affiliation":[{"name":"Engenharia Inform\u00e1tica, Universidade da Beira Interior, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4344-052X","authenticated-orcid":false,"given":"Tiago","family":"Marques","sequence":"additional","affiliation":[{"name":"CHAIA Center for Art History and Artistic Research, Universidade de \u00c9vora, 7004-516 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1006-545X","authenticated-orcid":false,"given":"Peter D.","family":"Finn","sequence":"additional","affiliation":[{"name":"Associate King\u2019s College Programme, King\u2019s College London, London WC2R 2LS, UK"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Marcel, S., and Rodriguez, Y. 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