A data compression apparatus includes: a type determination section which determines a type of data to be compressed; a difference generation section which obtains a difference between adjacent values in a sequence of values forming data to be compressed, and generates new data to be compressed; and an offset section which offsets each value forming the new data to be compressed by a predetermined value. The apparatus further includes a division section which divides values of the data to be compressed whose values are offset into a higher order bit portion and a lower order bit portion at a predetermined number of division bits lower than the number of unit bits, thereby dividing the data to be compressed into higher order data including a sequence of higher order bit portions of the values and lower order data including a sequence of lower order bit portions of the values.