| 摘要 |
PURPOSE:To execute dictionary retrieval at high speed and to obtain high compressibility by preparing a usefull dictionary for the data compressing system depending by an LZW code known as an improvement of an increment decomposition type as one kind of a universal code. CONSTITUTION:The frequency of appearance for each character in an input character string is counted, a dictionary 10 is prepared by registering and storing all the character strings having the cumulative value of the appearance frequency estimated from this appearance frequency at a fixed value decided in advance, and the input character string is compressed and coded while being expressed with the longest coincident character string in the dictionary 10. |
