SYSTEM AND METHOD FOR TRANSMITTING COMPRESSED DATA OR PRE-COMPRESSED DATA BASED ON A PRESET COMPRESSION RATIO

摘要

A difference/compression ratio calculating means 76 in a data processing means 71 of a data transmitting apparatus according to the present invention calculates an actual difference and an actual compression ratio based on the data length of pre-compression data received from a data source 2 through pre-compression data receiving means 74 and the data length of compressed data outputted from a data compression circuit 67. If the actual difference is equal to or greater than a preset difference .alpha. and the actual compression ratio is equal to and greater than a preset compression ratio .beta., then the compressed data is transmitted to a data destination 3 through a transfer request data output means 79. Otherwise, the pre-compression data is transmitted to the data destination 3. With this arrangement, it is possible to prevent a phenomenon in which the size of compressed data which occupies a storage area in the data destination 3 is substantially the same as the size of uncompressed data which occupies the storage area, and also to avoid wasteful data expansion in the data destination 3.