Pablo César Dick C. A. Bulterman David Geerts Jack Jansen Hendrik Knoche William Seager Enhancing social sharing of videos: fragment, annotate, enrich, and share. 11-20 2008 ACM Multimedia http://doi.acm.org/10.1145/1459359.1459362 conf/mm/2008 db/conf/mm/mm2008.html#CesarBGJKS08