| 摘要 |
PURPOSE:To obtain high compression effect by substituting a short code for continuous long data with a dictionary file. CONSTITUTION:A dictionary data reading means 3 reads the character column of data in a dictionary file 2 and a code corresponding to it and stores the whole contents in a dictionary data table 4 of an electronic computer 1. For the compression of the data, data before compression 8 are transferred to a data compressing means 6 at first. The means 6 shifts the transferred data by each one character from the top and transfers them to a dictionary table searching means 5. The means 5 compares the transferred character column with a data part in the table 4, and when they are coincident, the length of the coincident character column and the code are returned to the means 6. The means 6 generates compressed data 9 by the content returned from the means 5. Next, for the restoration of the data, data before restoring 10 are transferred to a data restoring means 7. When the control character of compression existing appears, the means 7 transfers the code following it to the means 5, obtains the original character column and transfers the content to the data 11 after restoring. |
