FLEXIBLE STORAGE OF MEDIA INFORMATION

摘要

Items of media information are stored in separately reusable blocks of memory. Items are split into a plurality of layers, so that the item can be represented at reduced quality by a subset of the layers without using a remainder of the layers. Each layer is stored in a respective one of the blocks. When information of a subsequent item is stored, a block for storing the information of the second item dependent on a number of blocks that is in use for storing information. An unused block is selected when the number of blocks that is in use is below a threshold number. When the number is above the threshold number a block is re-used that was previously used for storing a layer from said remainder. Preferably, when the layers are encrypted, different layers of the first item are encrypted independently of one another, so that each layer can be decrypted even if the remainder has been overwritten.