The purpose of the work is to discuss the fundamental issues and solutions in managing compressed and uncompressed multimedia data, especially voluminous continuous mediatypes (video, audio) and text in a memory hierarchy with four levels (main memory, magnetic disk, (optical or magnetic) on-line/near-line low-speed memory, and slow off-line memory, i.e. archive). We view the multimedia data in such a database to be generated, (compressed), and stored into the memory hierarchy (at the lowest non-archiving level), and subsequently retrieved, (decompressed), and presented. It unused, the data either travels down in the memory hierarchy or it is compressed and stored at the same level. We first discuss the general prerequisites of the memory hierarchy, like program locality and decreasing storage costs and performance of each deeper level. To discuss the issues in a greater depth a schematic four level memory hierarchy model is presented.
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