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A key problem encountered in such systems is the presence of flashers and obscene content. This problem is especially acute given the presence of underage minors in such systems. This article presents SafeVchat, a novel solution to the problem of flasher detection that employs an array of image detection algorithms. A key contribution of the article concerns how the results of the individual detectors are fused together into an overall decision classifying a user as misbehaving or not, based on Dempster-Shafer theory. The article introduces a novel, motion-based skin detection method that achieves significantly higher recall and better precision. The proposed methods have been evaluated over real-world data and image traces obtained from Chatroulette.com. SafeVchat has been deployed in Chatroulette. A combination of SafeVchat with human moderation has resulted in banning as many as 50,000 inappropriate users per day on Chatoulette. Furthermore, offensive content on Chatoulette has dropped significantly from 33.08% (before SafeVchat installation) to 3.49% (after SafeVchat installation).<\/jats:p>","DOI":"10.1145\/2499926.2499927","type":"journal-article","created":{"date-parts":[[2013,7,25]],"date-time":"2013-07-25T19:12:41Z","timestamp":1374779561000},"page":"1-26","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":3,"title":["SafeVchat"],"prefix":"10.1145","volume":"12","author":[{"given":"Yu-Li","family":"Liang","sequence":"first","affiliation":[{"name":"University of Colorado Boulder"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinyu","family":"Xing","sequence":"additional","affiliation":[{"name":"University of Colorado Boulder"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanqiang","family":"Cheng","sequence":"additional","affiliation":[{"name":"McGill University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianxun","family":"Dang","sequence":"additional","affiliation":[{"name":"McGill University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sui","family":"Huang","sequence":"additional","affiliation":[{"name":"Ohio State University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Richard","family":"Han","sequence":"additional","affiliation":[{"name":"University of Colorado Boulder"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xue","family":"Liu","sequence":"additional","affiliation":[{"name":"McGill University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qin","family":"Lv","sequence":"additional","affiliation":[{"name":"University of Colorado Boulder"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shivakant","family":"Mishra","sequence":"additional","affiliation":[{"name":"University of Colorado Boulder"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"320","published-online":{"date-parts":[[2013,7]]},"reference":[{"key":"e_1_2_1_1_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.inffus.2005.07.003"},{"key":"e_1_2_1_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/0167-8655(96)00039-6"},{"key":"e_1_2_1_3_1","unstructured":"Blurrypeople. 2010. 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