A data processing device for a storage device can include a dictionary storage unit that is configured to store a plurality of dictionaries and a compression unit that is configured to determine a selected dictionary from the plurality of dictionaries based on received data, and compress the received data using the selected dictionary to provide compressed data. Each of the plurality of dictionaries can include a plurality of pattern-symbol correspondence relations defining a one-to-one correspondence between respective ones of a plurality of patterns and respective ones of a plurality of symbols.