Masanori Sano Nobuyuki Yagi Norio Katayama Shin'ichi Satoh Image-based quiz generation from news video archives based on principal object. 929-932 2008 ACM Multimedia http://doi.acm.org/10.1145/1459359.1459524 conf/mm/2008 db/conf/mm/mm2008.html#SanoYKS08