| 摘要 |
PURPOSE:To offer a data compressing method capable of compressing data at a high compression ratio even when the appearance frequency of characters used in data to be compressed are average. CONSTITUTION:The distribution of characters used in data to be compressed which are included in a previously set compression applying range is checked, characters having high appearance frequency are extracted as the prescribed number of characters to be compressed based upon the distribution, corresponding codes are allocated to respective characters to be compressed extracted only by the prescribed number of characters, a diagram to be compressed which expresses the arrangement of characters not to be compressed and characters to be compressed as respective bit strings is prepared, and the data to be compressed are obtained by successively arraying the compression applying range, the characters to be compressed, the diagram to be compressed, and the characters not to be compressed. |
