| 摘要 |
PURPOSE:To efficiently read out arbitrary compressed data from a storing medium upon receiving a data readout request by retrieving file management information in a memory and selecting the packet storing the requested data. CONSTITUTION:A storing medium 1 is composed of plural fixed-length packets #0-#7 and compressed data are stored in the packets #1-#7 in a divided state. In addition, file management information including the information indicating the pieces of compressed data stored in each packet is stored in the packet #0. When software 3 requests the readout of arbitrary data stored in the storing medium 1, an extension processing section 2 checks whether or not the requested data exist in a buffer 8. When the data do not exist in the buffer 8, the section 2 reads out the packet storing the requested data from the medium 1, extends the data in the buffer 8 after canceling the compression, and delivers the requested data to the software 3. |
