| 摘要 |
PROBLEM TO BE SOLVED: To increase a compression degree and to shorten a time required for compressing data by reading a data stream into a window provided with a history buffer and look-ahead buffer, selecting the coindident part of a head part in the look-ahead buffer with a specified part in the history buffer and encoding its address and run-length. SOLUTION: The data stream is read into a sliding window provided with the history buffer and the look-ahead buffer. At first, only the first part of an input data stream is processed at the same time and written in an output file. After that, a following part is read in the window so as to be processed as the first part of the succeeding data stream. A part compared by the look- ahead buffer is designated as the second part and a part compared by the history buffer is as the third part. When the coincidence of the second part with the third part is recognized, the head address and run-length of the third part are outputted in a pair. |
