COMPRESSION DEVICE, COMPRESSION METHOD, COMPRESSION PROGRAM, EXPANSION DEVICE, EXPANSION METHOD, EXPANSION PROGRAM, AND COMPRESSION/EXPANSION SYSTEM

摘要

In one aspect of the present invention, a comparison process in data units that differ to data units constituting data to be compressed is suppressed with respect to data to be encoded. A compression program executes a process on a computer, whereby: a data sequence is acquired according to a data group in which a plurality of types of sizes of units constituting data exists; control is performed, whereby certain data included in the aforementioned data is compared with data having the same size of unit constituting the data as the aforementioned certain data among the data included in the data sequence; matching data, which matches the aforementioned certain data, is extracted from the data sequence according to a comparison process performed on the basis of the aforementioned control; and a compression code is generated according to the positional relationship in the data sequence between the aforementioned certain data and the matching data that was extracted.