| 摘要 |
<p>Data is compressed (20) and decompressed (28) using synthetic (30) history data. The synthetic history data is used to provide preliminary history data to a data compressor and a data decompressor at the start of data compression and data decompression operations, respectively. Several synthetic histories may be defined, each of which is associated with a given data type. The data type of data to be compressed may be ascertained to determine which synthetic history is to be used for that data. The synthetic history data may consist of 'typical text' that contains strings which are likely to appear in a document of a certain type. The 'typical text' is compressed to provide the preliminary history data.</p> |
