A traditional data warehouse will usually not contain structures within it. The data will be stored in tables and joined together and queried as required. Summary and dimensional tables are also built to improve performance and give dimensional views of the relational data.
With a multimedia warehouse, the focus is different. Each digital image is viewed as an object with its associated metadata describing that object. The objects are still queried in an ad hoc fashion, and dimensional and summary tables are still built, but the objects are put into structures to help manage and control them. For the user querying the warehouse, these structures might be hidden, or they might be used to add intelligence or control to the queries performed.
The following describes some of the structures that can be deployed into a multimedia warehouse. Whether these structures are actually used is dependent on the type of objects being stored and the purpose of the multimedia warehouse.