An information processing device for reading from a storage medium storing description information describing multimedia contents in a tree structure including a plurality of nodes at a first level correlated with a plurality of scenes divided in time series, respectively, for processing,
- said description information including a plurality of nodes at a second level, each correlated with one of said plurality of nodes at the first level, and for describing an item including at least an actor and/or a character,
- each of said plurality of nodes at the second level including a keyword that is an entity of said item,
- said description information configured by determining an overlapping keyword among keywords included in said plurality of nodes at the second level included in original description information, adding ID information representing the keyword to a node at the second level corresponding to at least one keyword located at a relatively earlier position in time series, among the overlapping keywords identified by the determination, and
- replacing each of the nodes at the second level corresponding to respective overlapping keywords located at a relatively later position in time series with respect to the keyword to which said ID information is added, with a reference node to specify said ID information,
- said information processing device comprising:
- means for accepting a selection of a keyword,
- means for obtaining ID information corresponding to the selected keyword and a reference node identifying the ID information from said description information stored in said storage medium, and
- means for retrieving a position where said keyword is located in said multimedia contents based on information of a scene correlated with each of a node to which the obtained ID information is added and the obtained reference node.