Patent ID: 7296285

Claim:
A method implemented by a data processing apparatus for describing user preferences, the method comprising: storing a multiple level hierarchical data structure for describing user preferences related to filtering and searching multimedia content, the hierarchical data structure having a tree structure in which a top container includes first and second parent preference objects at a first level in the tree structure, wherein the first parent preference object is a container having a plurality of child preference objects and the second parent preference object is a container having a single child preference object, the single child preference object and each child preference object in the plurality of child preference objects being located below the first level in the tree structure of the hierarchical data structure and representing one content description element describing multimedia content; assigning a first preference value to the first parent preference object to characterize user preference for the particular combination of the content description elements represented by the plurality of child preference objects; assigning a second preference value to the second parent preference object to characterize user preference for the content description element represented by the single child preference object; storing the first and second preference values in the first and second parent preference objects, respectively, in the hierarchical data structure for describing user preferences related to filtering and searching multimedia content; receiving content description information including a set of content description elements for a multimedia content stream, wherein the content description elements represented by the plurality of child preference objects of the first parent preference object form a subset of the set of content description elements for the multimedia content stream; and using the content description information and the hierarchical data structure with the first preference value to evaluate the multimedia content stream for searching and filtering.