{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:14:14Z","timestamp":1760177654771,"version":"build-2065373602"},"reference-count":15,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,7,22]],"date-time":"2020-07-22T00:00:00Z","timestamp":1595376000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>We propose an image-based class retrieval system for ancient Roman Republican coins that can be instrumental in various archaeological applications such as museums, Numismatics study, and even online auctions websites. For such applications, the aim is not only classification of a given coin, but also the retrieval of its information from standard reference book. Such classification and information retrieval is performed by our proposed system via a user friendly graphical user interface (GUI). The query coin image gets matched with exemplar images of each coin class stored in the database. The retrieved coin classes are then displayed in the GUI along with their descriptions from a reference book. However, it is highly impractical to match a query image with each of the class exemplar images as there are 10 exemplar images for each of the 60 coin classes. Similarly, displaying all the retrieved coin classes and their respective information in the GUI will cause user inconvenience. Consequently, to avoid such brute-force matching, we incrementally vary the number of matches per class to find the least matches attaining the maximum classification accuracy. In a similar manner, we also extend the search space for coin class to find the minimal number of retrieved classes that achieve maximum classification accuracy. On the current dataset, our system successfully attains a classification accuracy of 99% for five matches per class such that the top ten retrieved classes are considered. As a result, the computational complexity is reduced by matching the query image with only half of the exemplar images per class. In addition, displaying the top 10 retrieved classes is far more convenient than displaying all 60 classes.<\/jats:p>","DOI":"10.3390\/e22080799","type":"journal-article","created":{"date-parts":[[2020,7,22]],"date-time":"2020-07-22T07:31:28Z","timestamp":1595403088000},"page":"799","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["An Image-Based Class Retrieval System for Roman Republican Coins"],"prefix":"10.3390","volume":"22","author":[{"given":"Hafeez","family":"Anwar","sequence":"first","affiliation":[{"name":"Interdisciplinary Center for Digital Humanities and Social Sciences, Friedrich-Alexander University, 91052 Erlangen, Germany"},{"name":"Department of Electrical and Computer Engineering, COMSATS University Islamabad Attock Campus, Attock City 43600, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Serwah","family":"Sabetghadam","sequence":"additional","affiliation":[{"name":"Institute of Software Technology and Interactive Systems, Vienna University of Technology, 1040 Vienna, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Bell","sequence":"additional","affiliation":[{"name":"Interdisciplinary Center for Digital Humanities and Social Sciences, Friedrich-Alexander University, 91052 Erlangen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,22]]},"reference":[{"key":"ref_1","unstructured":"Crawford, M.H. (1974). Roman Republican Coinage, Cambridge University Press."},{"key":"ref_2","unstructured":"Zaharieva, M., Kampel, M., and Zambanini, S. (2007, January 27\u201329). Image based recognition of ancient coins. Proceedings of the International Conference on Computer Analysis of Images and Patterns (CAIP), Vienna, Austria."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Arandjelovi\u0107, O. (2010, January 13\u201318). Automatic attribution of ancient Roman imperial coins. Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR), San Francisco, CA, USA.","DOI":"10.1109\/CVPR.2010.5539841"},{"key":"ref_4","unstructured":"Zambanini, S., and Kampel, M. (2011, January 18\u201321). Automatic coin classification by image matching. Proceedings of the International Symposium on Virtual Reality, Archaeology and Cultural Heritage (VAST), Prato, Italy."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Zambanini, S., Kavelar, A., and Kampel, M. (2014, January 24\u201328). Classifying ancient coins by local feature matching and pairwise geometric consistency evaluation. Proceedings of the International Conference on Pattern Recognition (ICPR), Stockholm, Sweden.","DOI":"10.1109\/ICPR.2014.523"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1109\/MSP.2015.2409331","article-title":"Ancient Coin Classification Using Reverse Motif Recognition: Image-based classification of Roman Republican coins","volume":"32","author":"Anwar","year":"2015","journal-title":"IEEE Signal Proc. Mag."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1007\/s00138-015-0665-2","article-title":"Coarse-grained ancient coin classification using image-based reverse side motif recognition","volume":"26","author":"Anwar","year":"2015","journal-title":"Mach. Vis. Appl."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1145\/2583115","article-title":"Reading the Legends of Roman Republican Coins","volume":"7","author":"Kavelar","year":"2014","journal-title":"J. Comput. Cult. Herit."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Arandjelovi\u0107, O. (2012, January 7\u201313). Reading Ancient Coins: Automatically Identifying Denarii Using Obverse Legend Seeded Retrieval. Proceedings of the European Conference on Computer Vision (ECCV), Florence, Italy.","DOI":"10.1007\/978-3-642-33765-9_23"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Zambanini, S., and Kampel, M. (2013, January 9\u201313). Evaluation of Low-Level Image Representations for Illumination-Insensitive Recognition of Textureless Objects. Proceedings of the International Conference on Image Analysis and Processing (ICIAP), Naples, Italy.","DOI":"10.1007\/978-3-642-41181-6_8"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Kim, J., and Pavlovic, V. (2014, January 6\u20137). Improving Ancient Roman Coin Recognition with Alignment and Spatial Encoding. Proceedings of the ECCV Workshop on Computer Vision for Art Analysis, Zurich, Switzerland.","DOI":"10.1007\/978-3-319-16178-5_10"},{"key":"ref_12","unstructured":"Anwar, H., Anwar, S., Zambanini, S., and Porikli, F. (2019). CoinNet: Deep Ancient Roman Republican Coin Classification via Feature Fusion and Attention. arXiv."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Cooper, J., and Arandjelovic, O. (2019). Understanding Ancient Coin Images. arXiv.","DOI":"10.1007\/978-3-030-16841-4_34"},{"key":"ref_14","unstructured":"Zambanini, S., and Kampel, M. (2009, January 5\u20138). Robust Automatic Segmentation of Ancient Coins. Proceedings of the International Conference on Computer Vision Theory and Applications (VISAPP), Lisboa, Portugal."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Zambanini, S., and Kampel, M. (2013, January 17\u201320). A Local Image Descriptor Robust to Illumination Changes. Proceedings of the Scandinavian Conference on Image Analysis (SCIA), Espoo, Finland.","DOI":"10.1007\/978-3-642-38886-6_2"}],"container-title":["Entropy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1099-4300\/22\/8\/799\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:50:35Z","timestamp":1760176235000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1099-4300\/22\/8\/799"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,7,22]]},"references-count":15,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2020,8]]}},"alternative-id":["e22080799"],"URL":"https:\/\/doi.org\/10.3390\/e22080799","relation":{},"ISSN":["1099-4300"],"issn-type":[{"type":"electronic","value":"1099-4300"}],"subject":[],"published":{"date-parts":[[2020,7,22]]}}}